57 results on '"Jonathan C.H. Chan"'
Search Results
2. OCTA biomarkers in adults aged 50 and above: a prospective and cross-sectional community-based study
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Yan Kiu Li, Nicholas Siu-Kay Fung, Jonathan C.H Chan, Bonnie N.K. Choy, Loraine L.W. Chow, Kendrick C. Shih, Jasper K.W. Wong, and Ian Y.H. Wong
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Ophthalmology ,General Medicine - Abstract
Background/Aims To assess the normative values and parameters of optical coherence tomography angiography (OCTA) influencing the best corrected visual acuity (BCVA) in adults aged 50 and above. Methods This was a prospective cross-sectional study from an eye screening programme in Hong Kong for 4188 citizens aged 50 and above. Images were analysed using a validated quantification software calculating vessel density and capillary perfusion density (CPD), along with other OCTA parameters, such as the foveal avascular zone area (FAZ) and circularity. OCTA data was collected from May 2019 to December 2020, including a total of 4188 healthy eyes from 4188 subjects. Results Mean superficial vessel density (MSVD) was 14.48 ± 3.60 mm− 1, while the mean capillary perfusion density (MCPD) was 0.41 ± 0.06. Multivariate analysis revealed ageing (β = 0.321, p Conclusion High FAZ area and low FAZ circularity, low MSVD in the outer ring, specifically the nasal and temporal outer quadrants, and low MCPD in the outer superior quadrant can be used as biomarkers in predicting a low visual acuity in adults aged 50 and above.
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- 2023
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3. A differential effect of visual cortex tDCS on reading of English and Chinese in patients with central vision loss
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Andrew E. Silva, Anqi Lyu, Susan J. Leat, Shamrozé Khan, Tammy Labreche, Jonathan C.H. Chan, Qing Li, George C. Woo, Stanley Woo, Allen M.Y. Cheong, and Benjamin Thompson
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China ,Reading ,General Neuroscience ,Biophysics ,Humans ,Neurology (clinical) ,Transcranial Direct Current Stimulation ,Language ,Visual Cortex - Published
- 2022
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4. Association between functional status and ocular surface disease among local elderly population in Hong Kong
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Jason Chun Sum Pang, Patrick K C Chiu, Michelle Ching Yim Fan, Jonathan C.H. Chan, Bonnie Nga Kwan Choy, Joseph Kwan, Lawrence Pui Leung Iu, Alex L K Ng, Jimmy S. M. Lai, and Ming Ming Zhu
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medicine.medical_specialty ,Ocular surface disease ,business.industry ,Meibomian gland dysfunction ,Meibomian Glands ,General Medicine ,Middle Aged ,Ophthalmology ,Functional Status ,Tears ,Elderly population ,Internal medicine ,Activities of Daily Living ,Hong Kong ,Humans ,Medicine ,Chinese subjects ,Dry Eye Syndromes ,Functional status ,Ocular Surface Disease Index ,business ,Aged - Abstract
Purpose: To evaluate the correlation between ocular surface disease (OSD) and functional status among elderly population over 60 years old in Hong Kong.Methods: Chinese subjects above 60 years old ...
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- 2021
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5. Prevalence and Pattern of Geographic Atrophy in Asia
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Shih-Jen Chen, Marco Yu, Prabhat Nangia, Se Woong Kang, Jonathan C.H. Chan, Suganeswari Ganesan, Chui Ming Gemmy Cheung, Xiaohui Yang, Praveen Vashist, Gyulli M. Kazakbaeva, Ramasamy Kim, Charumathi Sabanayagam, Vaitheeswaran Kulothungan, Pei Quan Zhao, Astrid E. Fletcher, Jost B. Jonas, Fumihiko Matsuda, Rajiv Raman, Tung-Mei Kuang, Ravilla D. Ravindran, Kohta Fujiwara, Kenji Yamashiro, Nattapol Pokawattana, Ronnie George, Raba Thapa, Achareeya Saenmee, Rohit C Khanna, Kyu Hyung Park, Akitaka Tsujikawa, Tien Yin Wong, Jie Hao, Jae Pil Shin, Masahiro Miyake, Sang Jun Park, Kai Cao, Feifei Mao, Tarun Sharma, Ningli Wang, Songhomitra Panda-Jonas, Janani Surya, Ayako Takahashi, Takamasa Kayama, Timur R. Gilmanshin, Hyun Woong Kim, Ching-Yu Cheng, Jaeryung Oh, Ya Xing Wang, Tyler Hyungtaek Rim, Wen Bin Wei, Hiroyuki Namba, Watanee Jenchitr, Toru Takebayashi, Ryo Kawasaki, Sei Harada, Mariko Sasaki, Mukharram M. Bikbov, Koh Hei Sonoda, Periasamy Sundaresan, Qianli Meng, Vinay Nangia, Ian Y. H. Wong, Yasuo Yanagi, Hidetoshi Yamashita, Paisan Ruamviboonsuk, Usha Chakravarthy, Rinat M. Zainullin, Yih Chung Tham, Timur A. Khalimov, Seung-Young Yu, and G.H.M.B. van Rens
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0303 health sciences ,medicine.medical_specialty ,education.field_of_study ,business.industry ,Population ,Macular degeneration ,medicine.disease ,Confidence interval ,Pallor ,Geographic atrophy ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,Meta-analysis ,Epidemiology ,030221 ophthalmology & optometry ,medicine ,East Asia ,medicine.symptom ,education ,business ,030304 developmental biology ,Demography - Abstract
Purpose Although there have been many population-based studies of age-related macular degeneration (AMD), only limited information is available in Asia on the epidemiology of geographic atrophy (GA). We aimed to determine the prevalence and patterns of GA through an analysis of multiple studies conducted within the Asian Eye Epidemiology Consortium (AEEC). Design Cross-sectional meta-analyses. Participants A total of 97 213 individuals aged 40 years and older. Methods Data from 22 population-based studies from countries belonging to the AEEC were included. In all studies, AMD was defined on the basis of standardized grading systems. Geographic atrophy was defined as an area of pallor in the fundus with visibility of the underlying choroidal blood vessels and sharply defined borders. Random-effects meta-analysis was performed to estimate overall and age-, gender-, and region-specific pooled prevalence of GA. Main Outcome Measures Prevalence of GA per 1000 persons. Results The mean age was 60.8 ± 10.0 years, and 42 673 (43.9%) were male. Overall, a total of 223 individuals (0.2%) had GA. The pooled overall prevalence of GA was 1.57 per 1000 persons (95% confidence interval [CI], 1.04–2.10), which was 3 times less than that of neovascular AMD of 5.20 per 1000 persons (95% CI, 3.97–6.43). Compared with those aged 50 to 59 years, the prevalence of GA increased from 0.34 per 1000 persons (95% CI, 0.07–0.62) to 2.90 per 1000 persons (95% CI, 1.55–4.25) in those aged ≥70 years. The GA prevalence per 1000 persons was similar between urban (2.22; 95% CI, 1.22–3.23) and rural residents (1.33; 95% CI, 0.70–1.96). Geographic atrophy was more prevalent in South Asia (based on studies from India and Nepal, 3.82 per 1000 persons; 95% CI, 1.72–5.93) compared with East Asia (based on studies from China, Korea, Hong Kong, Taiwan, and Japan, and the Singapore Chinese Eye Study, 0.76 per 1000 persons; 95% CI, 0.31–1.22, P = 0.005). Conclusions Geographic atrophy is uncommon in Asian populations compared with those of European ancestry. Even within Asia, geographic differences in GA prevalence were seen. The findings of this meta-analysis suggest that better dissection of risk factors in the Asian population for GA may provide insights into the biological pathways that drive these late-stage manifestations, thus suggesting better targets for prevention.
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- 2020
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6. Incorporating Optical Coherence Tomography Macula Scans Enhances Cost-effectiveness of Fundus Photography-Based Screening for Diabetic Macular Edema
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Jonathan C.H. Chan, Ryo Kawasaki, Ian Y. H. Wong, Victor Chong, and Raymond Wong
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Male ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Cost effectiveness ,Cost-Benefit Analysis ,Endocrinology, Diabetes and Metabolism ,Diabetic macular edema ,Visual Acuity ,030209 endocrinology & metabolism ,Diagnostic Techniques, Ophthalmological ,Macular Edema ,Retina ,03 medical and health sciences ,0302 clinical medicine ,Optical coherence tomography ,Ophthalmology ,Photography ,Internal Medicine ,medicine ,Humans ,Mass Screening ,030212 general & internal medicine ,Radionuclide Imaging ,Aged ,Aged, 80 and over ,Advanced and Specialized Nursing ,Diabetic Retinopathy ,medicine.diagnostic_test ,business.industry ,Surrogate endpoint ,Diabetic retinopathy screening ,Fundus photography ,Middle Aged ,eye diseases ,Standard protocol ,Female ,medicine.symptom ,business ,Tomography, Optical Coherence - Abstract
OBJECTIVE To compare four screening strategies for diabetic macular edema (DME). RESEARCH DESIGN AND METHODS Patients attending diabetic retinopathy screening were recruited and received macular optical coherence tomography (OCT), in addition to visual acuity (VA) and fundus photography (FP) assessments, as part of the standard protocol. Two retina specialists provided the reference grading by independently assessing each subject’s screened data for DME. The current standard protocol (strategy A) was compared for sensitivity, specificity, quality-adjusted life-year (QALY) gained, and incremental cost-effectiveness ratio (ICER) with three alternative candidate protocols using a simulation model with the same subjects. In strategy B, macular hemorrhage or microaneurysm on FP were removed as surrogate markers for possible DME. Strategy C used best-corrected instead of habitual/pinhole VA and added central subfield thickness (CST) >290 μm on OCT in suspected cases as a confirmation marker for possible DME. Strategy D used CST >290 μm OCT in all subjects as a surrogate marker for suspected DME. RESULTS We recruited 2,277 subjects (mean age 62.80 ± 11.75 years, 43.7% male). The sensitivities and specificities were 40.95% and 86.60%, 22.86% and 95.63%, 32.38% and 100%, and 74.47% and 98.34% for strategies A, B, C, and D, respectively. The costs (in U.S. dollars) of each QALY gained for strategies A, B, C, and D were $7,447.50, $8,428.70, $5,992.30, and $4,113.50, respectively. CONCLUSIONS The high false-positive rate of the current protocol generates unnecessary referrals, which are inconvenient for patients and costly for society. Incorporating universal OCT for screening DME can reduce false-positive results by eightfold, while improving sensitivity and long-term cost-effectiveness.
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- 2020
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7. Prevalence and Causes of Visual Impairment and Blindness among Adult Chinese in Hong Kong – The Hong Kong Eye Study
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Ian Y. H. Wong, Jonathan C.H. Chan, Alex L K Ng, Gabriel M. Leung, Jasper K.W. Wong, Qi Sheng You, Tien Yin Wong, Michael Y. Ni, Jennifer W. H. Shum, Janice J. C. Cheung, Jimmy S. M. Lai, Kendrick Co Shih, and Bonnie Nk Choy
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Adult ,Male ,Gerontology ,China ,Adolescent ,Epidemiology ,Population ,Visual impairment ,Adult population ,Vision, Low ,Blindness ,Cataract ,Macular Edema ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Prevalence ,medicine ,Humans ,030212 general & internal medicine ,education ,Aged ,Aged, 80 and over ,education.field_of_study ,Diabetic Retinopathy ,business.industry ,Middle Aged ,medicine.disease ,Ophthalmology ,Cross-Sectional Studies ,030221 ophthalmology & optometry ,Hong Kong ,Female ,medicine.symptom ,business - Abstract
To investigate the prevalence, associations, and causes of visual impairment and blindness in the adult population of Hong Kong.This cross-sectional population-based study included 2018 (870, 43% male) randomly selected adults with a mean age 52 ± 16 years (range 18-90 years) in Hong Kong. Each participant underwent comprehensive ophthalmic examinations. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) of each eye was recorded. Prevalence of visual impairment and blindness was calculated using both World Health Organization (WHO) and United States (US) definitions, based on BCVA and PVA.Visual acuity measurements were available for 1952 (96.8%) participants. The prevalence of visual impairment, based on BCVA value, using WHO and US definition, was 1.0 ± 0.1% and 2.7 ± 0.4%, respectively. The prevalence of visual impairment, based on PVA value, was 5.1 ± 0.5% and 14.0 ± 0.8%, using WHO and US definition, respectively. Multivariate analysis demonstrated the presence of visual impairment (PVA, WHO definition) increased significantly with older age (odds ratio 1.039,The prevalence of visual impairment in Hong Kong increased significantly with older age and thinner central corneal thickness. The major causes for impairment were under-correction of refractive error, cataract, and age-related macular degeneration.
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- 2020
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8. Novel Drugs for Diabetes Also Have Dramatic Benefits on Hard Outcomes of Heart and Kidney Disease
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Michael C.Y. Chan and Jonathan C.H. Chan
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Glucose ,Diabetes Mellitus, Type 2 ,Cardiovascular Diseases ,Humans ,Kidney Diseases ,General Medicine ,Cardiology and Cardiovascular Medicine ,Sodium-Glucose Transporter 2 Inhibitors - Abstract
Background: Diabetes is a major risk factor for developing cardiovascular disease. Patients with both diabetes and cardiovascular disease have even higher mortality. The convergence of cardiology and diabetology therapy is an important step in treating patients and advancing research. Results: Major landmark trials and meta-analyses involving Sodium Glucose Cotransporter 2 inhibitors have shown dramatic clinical cardiorenal benefits in patients both with and without type 2 diabetes. In type 2 diabetes patients, Glucagon-like peptide-1 receptor agonists have been shown to improve major cardiac outcomes. Conclusion: This hot topic of research and clinical use of glucose lowering drugs intersects the fields of cardiovascular, renal, and diabetic medicine. The numerous cardiorenal benefits have led to the rapid adoption in clinical guidelines of these glucose lowering drugs in patients with Type 2 diabetes, cardiovascular disease, or renal disease.
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- 2022
9. Pharmacy, we have an image problem . . . (and here's a solution)
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Ross T. Tsuyuki, Talia M. Santarossa, Yazid N. Al Hamarneh, Jonathan C.H. Chan, Kaitlyn E. Watson, Jim Dobie, Randy So, and Queeny Wu
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Opinion ,business.industry ,Computer science ,Pharmaceutical Science ,Computer vision ,Pharmacy ,Artificial intelligence ,business ,Image (mathematics) - Published
- 2021
10. Effectiveness and Safety of Long Duration versus Short Duration Diode Laser Transscleral Cyclophotocoagulation
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Shing Chuen Chow, Jonathan C.H. Chan, and Jimmy Shiu-Ming Lai
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medicine.medical_specialty ,Intraocular pressure ,business.industry ,Glaucoma ,medicine.disease ,Laser ,law.invention ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,law ,Statistical significance ,Anesthesia ,030221 ophthalmology & optometry ,medicine ,Chinese subjects ,Laser pulse duration ,Complication ,business ,Short duration ,030217 neurology & neurosurgery - Abstract
Purpose To compare the efficacy and safety of diode laser transscleral cyclophotocoagulation using either the long duration or short duration protocol. Methods Retrospective series of 23 consecutive patients with glaucoma who underwent continuous-wave diode laser transscleral cyclophotocoagulation from August 2016 to July 2018 at a tertiary hospital in Hong Kong. Laser pulse duration for the long and short duration protocols was defined as 3.0-4.0 and 1.5-2.0 s, respectively. Results There were 15 male and 8 female Chinese subjects (23 eyes), age 49-90 (71.3 ± 2.7), with 10 subjects that underwent long duration cyclophotocoagulation (power 1239.2 ± 78.3 mW, spots 13.9 ± 1.4) and 13 subjects that had short duration cyclophotocoagulation (mean power 1817.3 ± 85.7 mW, spots 14.4 ± 1.0). Six months after long and short duration cyclophotocoagulation, intraocular pressure decreased significantly from 29.9 ± 7.8 to 21.1 ± 6.5 (p < 0.01), and from 35.4 ± 2.7 to 24.1 ± 3.4 (p = 0.04), respectively, while glaucoma medications decreased significantly by 1.4 ± 0.5 (p = 0.02) in the long duration group only. Reduction of medications after short duration cyclophotocoagulation was less and did not reach statistical significance (0.9 ± 0.9, p = 0.15). There was no significant difference of visual deterioration and complication rates. Conclusion Both types of cyclophotocoagulation were equally effective in lowering intraocular pressure by 6 months, but the short duration protocol, using higher laser power, was able to achieve a greater and earlier reduction, at 3 months. However, the long duration protocol, using less laser power, appears better at reducing medication requirement by 6 months.
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- 2020
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11. Review on the Use of Topical Ocular Hypertonic Saline in Corneal Edema
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Jonathan C.H. Chan and Shing-Chuen Chow
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Corneal hydrops ,Keratoconus ,medicine.medical_specialty ,genetic structures ,Administration, Ophthalmic ,Fuchs' dystrophy ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,medicine ,Humans ,Corneal epithelium ,Saline Solution, Hypertonic ,business.industry ,Corneal Edema ,medicine.disease ,eye diseases ,Recurrent corneal erosion ,Hypertonic saline ,Corneal Disorder ,medicine.anatomical_structure ,Treatment Outcome ,030221 ophthalmology & optometry ,Bullous keratopathy ,sense organs ,Ophthalmic Solutions ,business ,030217 neurology & neurosurgery - Abstract
Purpose To review the effectiveness of topical ocular hypertonic saline in corneal edema. Methods Online literature search of published articles on the effectiveness of topical hypertonic saline in corneal edema, bullous keratopathy (BK), and other associated corneal conditions in humans was performed on April 16, 2020. Results A total of 16 articles were reviewed after curation by the authors for relevance, with 4 randomized control trials, 6 prospective studies, 4 retrospective studies, and 2 case reports. Efficacy of hypertonic saline eye drops varied widely, depending on the specific corneal disorder being treated. Six of the studies involved BK (edema involves epithelium), 2 in corneal edema limited to the stroma, 5 in Fuchs dystrophy, 3 in filamentary keratitis (the presence of filaments attached to corneal epithelium), 2 in recurrent corneal erosion, and 1 in jellyfish stings. There was limited efficacy for hypertonic saline in BK, whereas clinical improvement was noted in most studies for corneal edema without epithelial involvement, especially if associated with Fuchs dystrophy or corneal hydrops in keratoconus. Hypertonic saline also seems to be beneficial for other corneal disorders, such as filamentary keratitis and jellyfish stings, but not in recurrent corneal erosion. Adverse effects from topical hypertonic saline include a mild stinging or burning sensation, with no serious complications having been reported. Conclusions Topical ocular hypertonic saline seems to be a safe and effective treatment in the management of less severe forms of corneal edema and other corneal disorders such as filamentary keratitis.
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- 2021
12. Aerosolization and Fluid Spillage During Phacoemulsification in Human Subjects
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Renyuan Qin, Jonathan C.H. Chan, Jasper K.W. Wong, Denvid Lau, Kendrick Co Shih, Jeremy Sze Wai John Kwok, and Jimmy Shiu-Ming Lai
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medicine.medical_specialty ,droplets ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,medicine.medical_treatment ,03 medical and health sciences ,Spillage ,0302 clinical medicine ,Ophthalmology ,Paracentesis ,Medicine ,aerosolization ,Aerosolization ,Original Research ,COVID ,Surgical team ,medicine.diagnostic_test ,business.industry ,Surgical wound ,Clinical Ophthalmology ,Phacoemulsification ,phacoemulsification ,030221 ophthalmology & optometry ,Operating microscope ,business ,030217 neurology & neurosurgery ,aerosols - Abstract
Jasper Ka Wai Wong,1 Jeremy Sze Wai John Kwok,1 Jonathan Cheuk Hung Chan,1 Kendrick Co Shih,1 âªRenyuan Qin,2 Denvid Lau,2 Jimmy Shiu Ming Lai1 1Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong; 2Department of Architecture and Civil Engineering, College of Engineering, City University of Hong Kong, Hong KongCorrespondence: Jimmy Shiu Ming LaiDepartment of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, Room 301, Block B, Cyberport 4, 100 Cyberport Road, Hong KongTel +852 39621405Email smjlai@netvigator.comBackground: Concerns had been raised for the potential hazard of SARS-CoV-2 transmissions via aerosols and fluid droplets during cataract surgeries amid the COVID-19 pandemic. This study aims to evaluate the rate of visible aerosol generation and fluid spillage from surgical wounds during phacoemulsification in human subjects.Methods: This is a prospective consecutive interventional case series. High-resolution video captures of 30 consecutive uncomplicated phacoemulsification surgeries, performed by 3 board-certified specialists in ophthalmology, were assessed by 2 independent and masked investigators for intraoperative aerosolization and fluid spillage. Water-contact indicator tape was mounted on the base of the operating microscope, around the objective lens, to detect any fluid contact.Results: No visible intraoperative aerosolization was detected in any of the cases, irrespective of different surgical practices among the surgeons with regard to wound size and position, lens fragmentation technique, power settings and means of ocular lubrication, or the different densities of cataract encountered. Large droplets spillage was noted from the paracentesis wounds in 70% of the cases. For all cases where fluid spill was detected on video, there was no fluid contact detected on the water-contact indicator tape.Conclusion: Visible aerosolization was not detected during phacoemulsification in our case series. Although the rate of fluid spillage was high, the lack of detectable contact with the indicator tape suggested that these large droplets posed no significant infectious risks to members of the surgical team.Keywords: phacoemulsification, aerosols, aerosolization, droplets, COVID
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- 2020
13. Optic disc and peripapillary vessel density measured with optical coherence tomography angiography and its associations in Chinese adults: a large population-based study
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Bonnie Nga Kwan Choy, Kendrick Co Shih, Ming Ming Zhu, Jimmy Shiu-Ming Lai, Michael Y. Ni, Alex L K Ng, Jonathan C.H. Chan, Jennifer Wh Shum, Gabriel M. Leung, Janice J. C. Cheung, Jasper K.W. Wong, Ian Y. H. Wong, and Qi Sheng You
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Adult ,Male ,medicine.medical_specialty ,Population ,Optic Disk ,Large population ,Glaucoma ,Cellular and Molecular Neuroscience ,Vessel density ,Ophthalmology ,Medicine ,Humans ,Fluorescein Angiography ,education ,Intraocular Pressure ,education.field_of_study ,business.industry ,Chinese adults ,Retinal Vessels ,Optical coherence tomography angiography ,Middle Aged ,medicine.disease ,Sensory Systems ,medicine.anatomical_structure ,Cross-Sectional Studies ,Optic nerve ,business ,Tomography, Optical Coherence ,Optic disc - Abstract
PurposeTo investigate the optic disc and peripapillary vessel density, as well as its ocular and systemic associations, in healthy eyes among adult Chinese population.MethodsA population-based cross-sectional eye survey was conducted on Chinese adults residing in Hong Kong. 1891 eyes from 1891 participants who completed 4.5×4.5 mm optical coherence tomography angiography scans were recruited. Among the 1891 eyes, 404 were excluded due to low scan quality, optic disc or retinal disorders and non-Chinese ethnicity. The vessel densities (VDs) at nerve fibre layer plexus (NFLP) at both optic disc and peripapillary were collected for analysis. Multiple linear regression analysis was performed to determine the ocular and systemic associations of NFLP VD.ResultsThe study included 1487 participants (men: 41.2%) with a mean age of 48.8±15.4 years. The mean NFLP VD of the whole en face image, inside disc and peripapillary region was 53.8%, 42.7% and 60.3%, respectively. In the multivariable model, decreased NFLP VDs were significantly associated with older age, male gender, longer axial length (AL) and lower Signal Strength Index.ConclusionsThis large population-based cross-sectional study provided quantitative data of optic disc and peripapillary NFLP VD which may serve as a normative reference for clinical use. Apart from age, gender and AL, the scan signal strength also should be taken into consideration during the assessment of NFLP VD.
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- 2020
14. Sociodemographic, behavioral, and medical risk factors associated with visual impairment among older adults: a community-based pilot survey in Southern District of Hong Kong
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Ian Y. H. Wong, Alex L K Ng, Kendrick Co Shih, Bonnie Nga Kwan Choy, Jordy Kin-Pong Lau, Jonathan C.H. Chan, and Perseus Wing-Fu Wong
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Visual impairment ,Population ,Vision Disorders ,Visual Acuity ,Pilot survey ,Disparities ,Stratified analysis ,03 medical and health sciences ,0302 clinical medicine ,lcsh:Ophthalmology ,Risk Factors ,Surveys and Questionnaires ,Prevalence ,medicine ,Humans ,030212 general & internal medicine ,Survey ,education ,Aged ,Community based ,education.field_of_study ,business.industry ,Confounding ,General Medicine ,medicine.disease ,Obesity ,Ophthalmology ,Cross-Sectional Studies ,Eye-level analysis ,lcsh:RE1-994 ,Medical risk ,030221 ophthalmology & optometry ,Hong Kong ,Interaction effect ,medicine.symptom ,business ,Research Article ,Demography - Abstract
Background The last visual survey of older adults in Hong Kong was a district-level study in 2002, with no assessment of behavioral and medical risk factors for visual impairment (VI). Our objectives were to determine the latest VI prevalence among older adults, significance of any spatial and temporal differences on the prevalence, and any associations of sociodemographic, behavioral and medical risk factors with VI from a multi-perspective analysis. Methods Community-based pilot survey of residents from a suburb of Hong Kong, aged ≥50, using a standardized questionnaire, was conducted in 2016. Results Of the 222 subjects, crude rates of bilateral and unilateral VI were 9.46 and 32.88%, respectively, or corresponding age-and-gender-adjusted rates of 6.89 and 30.5%. Older age and lower educational were associated with higher risk for unilateral VI, while older age, temporary housing, obesity and hyperlipidemia were associated with higher risk for bilateral VI. Smoking and alcohol-drinking status were not associated with unilateral or bilateral VI. Relative changes in ORs of hypertension or educational level on unilateral or bilateral VI were > 10% after adjusting for age. Interaction term between hyperlipidemia and gender or obesity was significant for unilateral VI. Gender, hypertension and cataract were not associated with unilateral or bilateral VI in general population of pooled analysis but were identified as risk factors in specific subgroups of stratified analysis. Refractive error (myopia or hyperopia) was significantly associated with VI in the eye-level analysis after adjusting the inter-eye correlation. Conclusions Sociodemographic and medical risk factors contributed to VI, but behavioral risk factors did not. Sociodemographic disparities of visual health existed. Age was the confounders of the VI-hypertension or VI-educational level relationships. Gender and obesity were more likely to have multiplicative effect on unilateral VI when combined with hyperlipidemia. Stratified analysis should be conducted to provide further insight into the risk factors for VI in specific populations. Uncorrected refractive error remains a significant cause of impaired vision. The spatial and temporal differences in bilateral VI prevalence from the previous local study indicates a territory-wide survey is needed to assess regional differences and overall prevalence of VI in Hong Kong.
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- 2020
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15. Videographic evaluation of aerosol generation during cataract surgery
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Jeremy J.S.W. Kwok, Jonathan C.H. Chan, Jimmy S. M. Lai, and Jasper K.W. Wong
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Aerosols ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Cataract Extraction ,Cataract surgery ,Sensory Systems ,Cataract ,Aerosol ,Ophthalmology ,Lens, Crystalline ,Medicine ,Humans ,Surgery ,business - Published
- 2020
16. Retrospective analysis of paediatric glaucoma at a tertiary referral centre in Hong Kong
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Jonathan C.H. Chan, Jimmy Shiu-Ming Lai, and Shing Chuen Chow
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Pediatrics ,medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,Open angle glaucoma ,Glaucoma ,Glaucoma valve ,Tertiary Care Centers ,03 medical and health sciences ,0302 clinical medicine ,Epidemiology ,medicine ,Humans ,Child ,Intraocular Pressure ,Retrospective Studies ,business.industry ,Incidence (epidemiology) ,Medical record ,General Medicine ,medicine.disease ,eye diseases ,Ophthalmology ,Treatment Outcome ,030221 ophthalmology & optometry ,Hong Kong ,sense organs ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Glaucoma, Open-Angle - Abstract
To evaluate the epidemiological features, clinical interventions, and outcomes of paediatric glaucoma in Hong Kong. Retrospective chart review. Clinical data from the medical records of all patients under 18 years of age diagnosed with glaucoma from January 2008 to December 2017 at a university-affiliated, tertiary referral centre were collected. The patients’ demographics, etiological distribution, clinical interventions, and outcomes were analysed. A total of 33 subjects (53 eyes) were identified, 30 (49 eyes) of whom were Chinese. Primary glaucoma accounted for 21.2% of subjects, while 78.8% were diagnosed with secondary glaucoma. The most common subtype was juvenile-onset open angle glaucoma, followed by Sturge-Weber Syndrome related glaucoma. The most commonly performed surgical interventions were tube-shunt surgery (Ahmed Glaucoma Valve) and transscleral cyclophotocoagulation. Most eyes had significant reduction in intraocular pressure after medical or surgical intervention, but deterioration of visual acuity remained common. Most cases of childhood glaucoma in Hong Kong are secondary rather than primary, similar to other regions with low incidence of parental consanguinity. The large proportion of secondary glaucoma which generally has poorer prognosis, is reflected by the frequency of multiple surgery, and a high incidence of visual deterioration despite significant intraocular pressure reduction in most eyes.
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- 2020
17. Maintenance of ophthalmic specialist out-patient service during the COVID-19 outbreak: The University of Hong Kong experience
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C. Kendrick Shih, Jonathan C.H. Chan, and Jimmy S. M. Lai
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Service (business) ,Ophthalmology ,2019-20 coronavirus outbreak ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pandemic ,Outbreak ,Medicine ,Medical emergency ,business ,medicine.disease ,Coronavirus Infections - Published
- 2020
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18. Macular Vessel Density Measured With Optical Coherence Tomography Angiography and Its Associations in a Large Population-Based Study
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Ian Y. H. Wong, Alex L K Ng, Michael Y. Ni, Kendrick Co Shih, Chui Ming Gemmy Cheung, Gabriel M. Leung, Jasper K.W. Wong, Jonathan C.H. Chan, Qi Sheng You, Jimmy S. M. Lai, Bonnie Nk Choy, Janice J. C. Cheung, Tien Yin Wong, and Jennifer W. H. Shum
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0301 basic medicine ,Adult ,Male ,medicine.medical_specialty ,Adolescent ,Cross-sectional study ,Population ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,Young Adult ,0302 clinical medicine ,Optical coherence tomography ,Reference Values ,Ophthalmology ,medicine ,Humans ,Macula Lutea ,Fluorescein Angiography ,education ,Aged ,Aged, 80 and over ,education.field_of_study ,Creatinine ,Slit Lamp ,medicine.diagnostic_test ,business.industry ,Retinal Vessels ,Retinal ,Optical coherence tomography angiography ,Middle Aged ,Capillaries ,030104 developmental biology ,Cross-Sectional Studies ,chemistry ,Regional Blood Flow ,Angiography ,030221 ophthalmology & optometry ,Female ,business ,Perfusion ,Tomography, Optical Coherence - Abstract
Purpose We investigate macular perfusion and the systemic and ocular associations in a population-based setting. Methods In this cross-sectional study, 2018 adults residing in Hong Kong underwent detailed ophthalmic examinations after consenting to participate. Macular perfusion was measured with optical coherence tomography angiography (OCTA) using the split-spectrum amplitude decorrelation angiography algorithm. The parafoveal flow index and vessel area density were quantified using automated custom-built software. Results Of the 2018 participants, the OCTA measurements were available for 1940, and 1631 (84.1%) had good quality scans. The right eyes of these 1631 participants (43.1% men) were included for final analysis. Mean age was 49.8 years (range, 18-92 years). Mean global macular vessel density was 47.3% and 55.1% for the superficial and deep retinal layers, respectively. In multivariate analysis, lower superficial vessel density remained significantly associated with lower signal strength index (SSI; P < 0.001, standardized β = 0.607) and male sex (P < 0.001, β = 0.162), and borderline associated with older age (P = 0.09, β = -0.045) and longer axial length (AL; P = 0.09, β = -0.037), while lower deep layer vessel density was significantly associated with lower SSI (P < 0.001, standardized β = 0.667), longer AL (P < 0.001, β = -0.097), and higher creatinine (P < 0.001, β = -0.072). Conclusions This large population-based study provided normative OCTA data of macular vessel density and demonstrated that a lower superficial retinal vessel density was significantly associated with lower SSI and male sex, while a lower deep layer retinal vessel density was significantly associated with lower SSI, longer AL, and higher level of creatinine. These associations must be considered when interpreting clinical quantitative OCTA data.
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- 2019
19. Is kidney function associated with primary open-angle glaucoma? Findings from the Asian Eye Epidemiology Consortium
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Songhomitra Panda-Jonas, Qianli Meng, Tyler Hyungtaek Rim, Vinay Nangia, Hua Zhong, Ian Y. H. Wong, Charumathi Sabanayagam, Liang Zhang, Sahil Thakur, Jost B. Jonas, Kai Cao, Yijin Tao, Miao Li Chee, Jonathan C.H. Chan, Ningli Wang, Mukharram M. Bikbov, Yih Chung Tham, Ya Xing Wang, Tien Yin Wong, Ching-Yu Cheng, Gyulli M. Kazakbaeva, Zhi Wei Lim, and Jie Hao
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Adult ,Male ,medicine.medical_specialty ,Asia ,genetic structures ,Population ,Glaucoma ,Renal function ,Kidney ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Tonometry, Ocular ,0302 clinical medicine ,Asian People ,Diabetes mellitus ,Internal medicine ,Epidemiology ,Medicine ,Humans ,Renal Insufficiency, Chronic ,education ,Intraocular Pressure ,Aged ,Creatinine ,education.field_of_study ,business.industry ,Middle Aged ,medicine.disease ,eye diseases ,Sensory Systems ,Ophthalmology ,Epidemiologic Studies ,Cross-Sectional Studies ,chemistry ,030221 ophthalmology & optometry ,Visual Field Tests ,Female ,Visual Fields ,business ,Body mass index ,030217 neurology & neurosurgery ,Glaucoma, Open-Angle ,Kidney disease ,Glomerular Filtration Rate - Abstract
AimTo comprehensively examine the association between kidney function and primary open angle glaucoma (POAG) in a large consortium of multiple Asian population-based studies.Methods28 925 participants (57 340 eyes) from 9 population-based studies (from China, Hong Kong, India, Korea, Russia, Singapore) of the Asian Eye Epidemiology Consortium were included. Across all studies, POAG was defined based on the International Society of Geographical and Epidemiological Ophthalmology criteria. Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine. Chronic kidney disease (CKD) was defined as eGFR2. Eye-specific data were pooled from each study. Multivariable regression analysis with generalised estimating equation models was performed to evaluate the associations between kidney function with POAG and intraocular pressure (IOP).ResultsAfter adjusting for age, gender, study group, hypertension, diabetes, hyperlipidaemia, body mass index, smoking status and IOP, lower eGFR (per 10 mL/min/1.73 m2 decrease) was not significantly associated with POAG (OR=1.01; p=0.77). Presence of CKD was also not significantly associated with POAG (OR=1.01; p=0.739). Furthermore, lower eGFR and presence of CKD were not associated with IOP (all p≥0.12), However, in the subgroup of combined Korean and Chinese individuals, significant associations between lower eGFR (OR=1.09; 95% CI 1.00 to 1.18; p=0.048) and severe kidney function decline (2; OR=2.57; 95% CI 1.34 to 4.93; p=0.004) with POAG, were observed.ConclusionIn this large pooled-analysis of multiple Asian population-based studies, our findings suggest that the association between CKD and POAG may only be present in East Asians specifically but not in the overall Asian population. Further evaluation in Japanese population is warranted to confirm this observation.
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- 2019
20. Prospective study on a novel treatment for leaking cystic bleb: Efficacy and safety of collagen crosslinking
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Ming M. Zhu, Wing Lau Ho, Bai B. Li, Jonathan C.H. Chan, Bonnie Nga Kwan Choy, Yu Cai, and Jimmy Shiu-Ming Lai
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Adult ,Male ,Leak ,medicine.medical_specialty ,Conjunctiva ,genetic structures ,Ultraviolet Rays ,Riboflavin ,Glaucoma ,Ocular Hypotension ,030226 pharmacology & pharmacy ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Medicine ,Prospective Studies ,Prospective cohort study ,Intraocular Pressure ,Aged ,Aged, 80 and over ,Photosensitizing Agents ,business.industry ,Outcome measures ,Middle Aged ,medicine.disease ,eye diseases ,Surgery ,Ophthalmology ,Cross-Linking Reagents ,Treatment Outcome ,medicine.anatomical_structure ,Photochemotherapy ,Filtering Surgery ,030221 ophthalmology & optometry ,Ultraviolet irradiation ,Female ,Collagen ,sense organs ,Bleb (medicine) ,business ,Single session ,Glaucoma, Open-Angle ,Follow-Up Studies - Abstract
Importance Management of cystic bleb leak is difficult. It would be essential to look for a method to strengthen the original pathological conjunctiva and reverse bleb leak. Background To evaluate the long-term efficacy and safety of collagen crosslinking in patients with leaking cystic bleb. Design Prospective interventional case series at a university-based hospital. Participants Twelve eyes in 12 subjects with late-onset bleb leak from cystic bleb, without indications for prompt surgical interventions were included. Methods The subjects underwent crosslinking with 0.1% riboflavin application to bleb surface, followed by ultraviolet irradiation for 30 minutes. The subjects were followed up at baseline and at 1 week, 1 month, 3 months, 6 months post-treatment and then every 6 months afterwards. Main outcome measures Interval from treatment to cessation of bleb leak, recurrence rate of bleb leak and side effects of treatment. Results The mean follow-up after crosslinking was 29.33 ± 12.45 months. Bleb leak subsided in 11 (92%) of 12 patients after a single session of crosslinking, after 1 to 8 weeks (median 3 weeks). Time to leak cessation was significantly correlated with the number of prior glaucoma interventions (R = .71, P = .014). Bleb wall at 3 months was significantly thicker than at baseline (0.70 ± 0.67 vs 0.81 ± 0.62 mm, P = .008). None of the patients experienced any complications. Conclusions and relevance Crosslinking achieves resolution of cystic bleb leak which lasts for at least 12 months, without the need of subsequent surgical interventions. Crosslinking is a simple, non-invasive treatment for bleb leak. It aims to restore the integrity of conjunctiva.
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- 2019
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21. Effect of Vitamin D3 on Regulating Human Tenon's Fibroblasts Activity
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Shuo Jia, Jonathan C.H. Chan, Kin Chiu, Gandhervin Kesavamoorthy, Huogang Wang, Jimmy Shiu-Ming Lai, Fushun Chen, and Ian Yat-Hing Wong
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calcitriol ,vitamin D3 ,Vitamin ,Mitomycin ,Biomedical Engineering ,Vitamin D3 24-Hydroxylase ,Pharmacology ,Article ,chemistry.chemical_compound ,CYP24A1 ,Fibrosis ,medicine ,Humans ,pterygium ,Cytotoxicity ,Cells, Cultured ,Cholecalciferol ,Chemistry ,Transdifferentiation ,RNA sequencing ,Fibroblasts ,medicine.disease ,human Tenon's fibroblasts (HTF) ,eye diseases ,In vitro ,Ophthalmology ,glaucoma - Abstract
Purpose To study the in vitro effect of vitamin D3 on the healing response of human Tenon's fibroblasts (HTF) and its possible role in preventing excessive postoperative subconjunctival fibrosis. Methods Effect of vitamin D3 on cytotoxicity and cell survival of primary cultured HTF was measured by lactate dehydrogenase and PrestoBlue assays, respectively. Proliferation and migration of vitamin D3-treated HTF (D3-HTF) was determined by CyQUANT proliferation and scratch assay, respectively. The mRNA expression profiles of control-HTF and D3-HTF from six subjects (three with glaucoma and long-term use of topical medications, three with primary pterygium) were assessed by RNA sequencing analyses to identify potential biomarkers for the inhibitory effect on HTF by vitamin D3. Validation of these biomarkers and their potential pathways were performed by quantitative real-time polymerase chain reaction (qRT-PCR) detection. Results Pure monolayers of HTF from controls (retinal detachment or squint surgeries), pterygium, and glaucoma subjects were successfully prepared and passaged. Proliferation and migration of pterygium and glaucoma HTF were inhibited by vitamin D3 in a dose-dependent manner, and without cytotoxicity or decrease in cellular viability with concentrations up to 10 µM. The qRT-PCR results were consistent with the transcriptome analyses, vitamin D3 appears to enhance CYP24A1, SHE, KRT16 but suppresses CILP expression in HTF. Conclusions Vitamin D3 can inhibit the in vitro activity of HTF without compromising cellular survivability at concentration up to 10 µM. This has potential clinical application for improving the outcome of pterygium and filtering surgeries. Translational relevance Vitamin D3 can suppress the in vitro proliferation, migration, and transdifferentiation of human Tenon's fibroblasts, without the cytotoxicity of mitomycin-C, the current standard antifibrotic agent in clinical use.
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- 2021
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22. Tele-ophthalmology amid COVID-19 pandemic—Hong Kong experience
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Jasper K.W. Wong, Jonathan C.H. Chan, Jimmy S. M. Lai, and Kendrick Co Shih
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2019-20 coronavirus outbreak ,Eye Diseases ,Coronavirus disease 2019 (COVID-19) ,SARS-CoV-2 ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,COVID-19 ,Comorbidity ,medicine.disease ,Telemedicine ,Sensory Systems ,Cellular and Molecular Neuroscience ,Ophthalmology ,Political science ,Pandemic ,medicine ,Hong Kong ,Humans ,Medical emergency ,Letter to the Editor ,Pandemics - Published
- 2020
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23. Pharmacists can improve hypertension care (but you have to pay them . . .): A review of remuneration opportunities across Canada
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Ross T. Tsuyuki and Jonathan C.H. Chan
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Opinion ,Nursing ,business.industry ,MEDLINE ,Remuneration ,Pharmaceutical Science ,Medicine ,Pharmacy ,business - Published
- 2020
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24. Prospective Study on the Efficacy of Treating Normal Tension Glaucoma With a Single Session of Selective Laser Trabeculoplasty
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Jacky W. Y. Lee, Jonathan C.H. Chan, Jimmy S. M. Lai, and RA Gangwani
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Male ,Intraocular pressure ,medicine.medical_specialty ,genetic structures ,Selective laser trabeculoplasty ,medicine.medical_treatment ,Gonioscopy ,Glaucoma ,Trabeculectomy ,Lasers, Solid-State ,Cohort Studies ,Normal tension glaucoma ,Ophthalmology ,Glaucoma surgery ,medicine ,Humans ,Low Tension Glaucoma ,Prospective Studies ,Prospective cohort study ,Intraocular Pressure ,Aged ,medicine.diagnostic_test ,business.industry ,medicine.disease ,eye diseases ,Treatment Outcome ,Female ,sense organs ,Visual Fields ,business - Abstract
PURPOSE The purpose of this study was to investigate the efficacy of selective laser trabeculoplasty (SLT) in the treatment of normal tension glaucoma (NTG). METHODS This prospective cohort study recruited consecutive cases of NTG on antiglaucoma medication. Cases were excluded for previous glaucoma surgery or laser. All patients underwent a 1-month washout of medication followed by a mean baseline intraocular pressure (IOP) measured at 9 AM, 1 PM, and 5 PM. A 30% reduction from baseline was set as the target IOP. A single session of SLT was performed to 360 degrees of the trabecular meshwork. IOP phasing was repeated at 1 month after SLT and medication was resumed to achieve the target IOP. Patients were followed up to 6 months after SLT. RESULTS In 83 eyes of 46 subjects, the mean prestudy IOP was 14.2 ± 3.1 mm Hg when on 1.5 ± 0.9 antiglaucoma medication. The mean baseline IOP without medication was 16.1 ± 2.2 mm Hg. The mean SLT shots applied was 187.8 ± 27.5 using a mean energy of 1.0 ± 0.07 mJ. At 1-month post-SLT, the IOP was 12.7 ± 2.0 mm Hg (21.6% IOP reduction) from baseline without medication (P
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- 2015
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25. Systematic review and meta-analysis on the efficacy of selective laser trabeculoplasty in open-angle glaucoma
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Jonathan C.H. Chan, Bonnie Nga Kwan Choy, Jacky Wai Yip Lee, Jimmy S. M. Lai, and Mandy Oi Man Wong
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medicine.medical_specialty ,Intraocular pressure ,genetic structures ,Open angle glaucoma ,Selective laser trabeculoplasty ,business.industry ,Glaucoma ,Argon laser trabeculoplasty ,Trabeculectomy ,medicine.disease ,eye diseases ,Alternative treatment ,Surgery ,Ophthalmology ,Trabecular Meshwork ,Meta-analysis ,Humans ,Medicine ,Laser Therapy ,sense organs ,business ,Macular edema ,Glaucoma, Open-Angle ,Intraocular Pressure - Abstract
Selective laser trabeculoplasty (SLT) is a relatively new type of laser used in treating open-angle glaucoma (OAG) and is reported to be equally efficacious to a first-line medication and argon laser trabeculoplasty (ALT). We summarize available evidence for considering SLT as an alternative treatment in OAG through systematic review and meta-analysis. Among OAG patients who range from newly diagnosed to those on maximally tolerated medical therapy, SLT results in a 6.9-35.9% intraocular pressure (IOP) reduction. Complications are rare and include an IOP spike requiring surgery, persistent macular edema, and corneal haze and thinning. Meta-analysis of randomized, controlled trials shows that SLT is non-inferior to ALT and medication in IOP reduction and also in achieving treatment success. Number of medications reduction is similar between SLT and ALT. More robust evidence is needed to determine its efficacy as a repeated procedure.
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- 2015
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26. Numerical and experimental analysis of heat transfer in turbulent flow channels with two-dimensional ribs
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Wing Bun Lee, Hao Wang, Jonathan C.H. Chan, and Suet To
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Pressure drop ,Engineering ,Computer simulation ,business.industry ,Turbulence ,Flow (psychology) ,Energy Engineering and Power Technology ,Mechanical engineering ,Reynolds number ,Mechanics ,Industrial and Manufacturing Engineering ,symbols.namesake ,Heat flux ,Heat transfer ,symbols ,business ,Dimensionless quantity - Abstract
The repeated ribs surfaces are known for their effective enhancement of heat transfer, which is widely demanded in many scientific and industrial applications. In this paper, further improvements were made by the introduction of a textured asymmetric arc rib structure, on which arrays of secondary micro grooves are superimposed onto a primary asymmetric surface. Numerical simulation has been carried out on the turbulent force convection flow in a single-phase channel with two-dimension (2D) ribbed internal surface in the range of Reynolds number from 20,000 to 60,000. A uniform heat flux is applied on the external surface of channel. In contrast to the conventional optimized symmetric triangular rib, the advanced compound rib could improve the performance of heat transfer while minimizes the pressure drop. These improvements are closely correlated to the promotion of the separated flow which could reattach the channel surface. Since the geometry of the novel compound rib is difficult to fabricate by conventional means, ultra-precision raster milling (UPRM) is used to generate these micro-structures. According to prediction of numerical simulation, the experimental cooling works have been designed and conducted for the considered shaped ribs with the significant dimensionless pitch of 5 and 6. A good agreement was found between the simulation and experimental results.
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- 2015
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27. Physical exercise and glaucoma: a review on the roles of physical exercise on intraocular pressure control, ocular blood flow regulation, neuroprotection and glaucoma-related mental health
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Kwok-Fai So, Jonathan C.H. Chan, Jimmy S. M. Lai, Bonnie Nga Kwan Choy, Alex L K Ng, Amy C. Y. Lo, Jennifer W. H. Shum, and Ming Ming Zhu
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medicine.medical_specialty ,Intraocular pressure ,genetic structures ,Visual impairment ,Glaucoma ,Physical exercise ,Neuroprotection ,Retinal ganglion ,Optic neuropathy ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,Medicine ,Humans ,Exercise ,Intraocular Pressure ,business.industry ,General Medicine ,medicine.disease ,eye diseases ,Exercise Therapy ,Neuroprotective Agents ,030221 ophthalmology & optometry ,Disease Progression ,Anxiety ,sense organs ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
The benefits of physical exercise on health and well-being have been studied in a wide range of systemic and ocular diseases, including glaucoma, a progressive optic neuropathy characterized by accelerated apoptosis of retinal ganglion cells (RGCs). Elevated intraocular pressure (IOP) and insufficient ocular perfusion have been postulated to be the two main theories in glaucoma development and progression. The effects of exercise in these two aspects have been demonstrated by numerous researches. A review in 2009 focusing on these two theories concluded that exercise results in transient IOP reduction but an inconsistent elevation in ocular perfusion. However, the majority of the studies had been conducted in healthy subjects. Over the past decade, technological advancement has brought forth new and more detailed evidence regarding the effects of exercise. Moreover, the neuroprotective effect of exercise by upregulation of neurotrophin and enhancement of mitochondrial function has been a focus of interest. Apart from visual impairment, the mental health issues in patients with glaucoma, which include anxiety and depression, should also be addressed. In this review, we mainly focus on publications from the recent years, so as to provide a comprehensive review on the impact of physical exercise on IOP, ocular perfusion, neuroprotection and mental health in patients with glaucoma.
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- 2017
28. Exophthalmometry values in the Hong Kong Chinese adult population from a population-based study
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Alex L K Ng, Gabriel M. Leung, Kendrick Co Shih, Jennifer W. H. Shum, Jasper K.W. Wong, Bonnie Nga Kwan Choy, Michael Y. Ni, Ian Y. H. Wong, Janice J. C. Cheung, Dulcia L. Chang, Jonathan C.H. Chan, and Jimmy S. M. Lai
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Adult ,Male ,exophthalmometry values ,Waist ,Adolescent ,Body height ,Adult population ,Observational Study ,Diagnostic Techniques, Ophthalmological ,Hertel's ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Asian People ,Ethnicity ,Exophthalmos ,Humans ,Medicine ,030212 general & internal medicine ,Aged ,Aged, 80 and over ,Chinese ,business.industry ,proptosis ,Significant difference ,General Medicine ,Middle Aged ,Population based study ,030220 oncology & carcinogenesis ,Cohort ,Hong Kong ,Female ,epidemiology ,Interpupillary distance ,business ,Body mass index ,Research Article ,Demography - Abstract
This study aims to establish the range of exophthalmometry values (EV) in the adult Hong Kong (HK) Chinese population, its relationship with various anthropometric parameters, and to compare it with the EV in different ethnic groups. About 1485 adult HK Chinese were drawn from a random sample from the community-based FAMILY Cohort. Participants were interviewed, and comprehensive ophthalmological assessments were conducted. EV was measured using the Hertel's exophthalmometer. EV of both eyes from 630 male (42.4%) and 855 female (57.6%) participants, mean age 54 ± 17.2 and 52 ± 16 respectively were analyzed. The mean EV were found to be 15.3 ± 2.8 mm in the right eye, 15.2 ± 2.9 mm in the left eye for men and 14.4 ± 2.7 mm in the right eye, 14.3 ± 2.7 mm in the left eye for women. There were no differences in the EV between right and left eyes (P > .05). Men had significantly higher EV than women (P
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- 2019
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29. Predictors of Success in Selective Laser Trabeculoplasty for Chinese Open-angle Glaucoma
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Jonathan C.H. Chan, Jimmy S. M. Lai, Jacky W. Y. Lee, and Catherine Chunling Liu
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Male ,medicine.medical_specialty ,Multivariate analysis ,genetic structures ,Open angle glaucoma ,Visual Acuity ,Glaucoma ,Cell Count ,Trabeculectomy ,Lasers, Solid-State ,Tonometry, Ocular ,Asian People ,Normal tension glaucoma ,Ophthalmology ,medicine ,Humans ,Low Tension Glaucoma ,Prospective Studies ,Prospective cohort study ,Antihypertensive Agents ,Intraocular Pressure ,Univariate analysis ,business.industry ,Endothelium, Corneal ,Odds ratio ,Middle Aged ,Prognosis ,medicine.disease ,eye diseases ,Visual field ,Female ,Laser Therapy ,sense organs ,Visual Fields ,business ,Glaucoma, Open-Angle - Abstract
Aim To investigate the determinants of success of selective laser trabeculoplasty (SLT) in Chinese open-angle glaucoma patients. Methods This prospective cohort study sequentially recruited Chinese subjects with unilateral or bilateral primary open-angle glaucoma (POAG) or normal tension glaucoma (NTG). All subjects received a single session of 360-degree SLT treatment. Success was defined as IOP reduction ≥20%. The following were analyzed in univariate and multivariate regression analyses for association with SLT success: type of glaucoma, age, sex, lens status, presenting IOP, pre-SLT IOP, day 1 IOP, 1-week IOP, number and type of anti-glaucoma medications, number of SLT shots and energy, retinal nerve fiber layer (RNFL) thickness, Visual Field Index, endothelial cell count, central corneal thickness, Snellen visual acuity, and spherical equivalent. Results In 111 eyes of 65 subjects, there were 51 POAG eyes and 60 NTG eyes. The overall success was 53.15% with a mean IOP reduction of 19.81±15.93%. In univariate analysis, a thinner RNFL [coefficient=-0.027; odds ratio (OR)=0.95; P=0.017] was associated with success. In multivariate analysis, a lower day 1 IOP (coefficient=-0.29; OR=0.75; P=0.049) and using topical carbonic anhydrase inhibitors (CAI) (coefficient=2.92; OR=18.63; P=0.0020) were associated with success. In both univariate and multivariate analyses, a higher pre-SLT IOP significantly predicted success (coefficient=0.20/0.46; OR=1.23/1.58; P=0.0017/0.0011) and using 3 anti-glaucoma medications (coefficient=-1.08/-3.74; OR=0.3/0.024; P=0.037/P=0.0081) was associated with SLT failure. Conclusion The positive predictors of SLT success included: higher pre-SLT IOP, use of topical CAI, thinner RNFL, and lower day 1 IOP. Using 3 anti-glaucoma medications was associated with failure.
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- 2014
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30. Impact of JAK2V617F mutation on thrombosis and myeloid transformation in essential thrombocythemia: a multivariate analysis by Cox regression in 141 patients
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Martin Law, Bonnie Kho, Chi-Chung Chan, L. G. Wong, J. P. Sim, YL Kwong, Jonathan C.H. Chan, Chor Sang Chim, and Rhs Liang
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Adult ,Male ,Oncology ,Aging ,medicine.medical_specialty ,Pathology ,Myeloid ,Multivariate analysis ,Medical Records ,Hemoglobins ,Leukocyte Count ,Young Adult ,Risk Factors ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,Point Mutation ,Genetic Association Studies ,Aged ,Retrospective Studies ,Aged, 80 and over ,Univariate analysis ,Proportional hazards model ,Essential thrombocythemia ,business.industry ,Thrombosis ,Hematology ,Janus Kinase 2 ,Middle Aged ,medicine.disease ,Survival Analysis ,medicine.anatomical_structure ,Leukemia, Myeloid ,Multivariate Analysis ,Cohort ,Female ,Hemoglobin ,business ,Thrombocythemia, Essential - Abstract
To perform a multivariate analysis by Cox proportional hazard model of the impact of JAK2 V617F mutation on thrombosis and myeloid transformations in patients with essential thrombocythemia (ET).The clinicopathologic features and outcome of a cohort of Chinese ET patients were retrospectively reviewed. JAK2 V617F mutation was detected by allele-specific polymerase chain reaction. Potential risk factors including JAK2 V617F that might impact on thrombosis and outcome were studied by multivariate analysis with Cox proportional hazard model.Of 141 patients studied, JAK2 V617F was found in 80 cases (57%). JAK2 V617F was positively correlated with hemoglobin and leukocyte count at diagnosis. Univariate analysis showed significant thrombotic risks to be JAK2 V617F (P=0.006), hemoglobin13 g/dl (P=0.015), and age55 years (P=0.011). However, in multivariate analysis, only age and hemoglobin were independent risk factors. JAK2 V617F was unrelated to survival or leukemic/myelofibrotic transformation.In Chinese patients with ET, JAK2 V617F was positively associated with age, hemoglobin, and leukocyte count, but was not an independent risk for thrombosis.
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- 2010
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31. Collagen crosslinking in the management of leaking cystic blebs: a prospective study
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Jimmy S. M. Lai, Ming Ming Zhu, Jennifer W. H. Shum, Wing Lau Ho, Bonnie Nga Kwan Choy, Jonathan C.H. Chan, and Alex L K Ng
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Male ,Pathology ,medicine.medical_specialty ,genetic structures ,Ultraviolet Rays ,Riboflavin ,Treatment outcome ,Visual Acuity ,Trabeculectomy ,macromolecular substances ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Tonometry, Ocular ,0302 clinical medicine ,Surgical Wound Dehiscence ,Medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Intraocular Pressure ,Aged ,Aged, 80 and over ,Photosensitizing Agents ,business.industry ,technology, industry, and agriculture ,Middle Aged ,eye diseases ,Sensory Systems ,Ophthalmology ,Cross-Linking Reagents ,Treatment Outcome ,Photochemotherapy ,030221 ophthalmology & optometry ,Female ,sense organs ,Collagen ,business ,Conjunctiva ,030217 neurology & neurosurgery ,Glaucoma, Open-Angle - Abstract
To evaluate the effectiveness and safety of collagen crosslinking for leaking cystic blebs.A prospective study was conducted on subjects with cystic bleb leaks without indications for urgent surgical intervention. Collagen crosslinking with riboflavin 0.1 % and ultraviolet A irradiation for 30 min was applied to the cystic bleb surface in five patients. Subjects were followed up for at least 20 weeks (mean: 35.5 ± 11.5 weeks) to monitor the length of time to the cessation of bleb leak, as well as visual acuity, intraocular pressure, and the presence of adverse effects arising from the treatment.Results showed that a single session of collagen crosslinking was effective in stopping cystic bleb leak. In two of the five subjects, the bleb leak subsided 1 week post-treatment, in one patient after 2 weeks, and in the two more complicated cases, after 4 weeks. This effect was maintained for a mean period of 33.5 ± 10.2 weeks after bleb leak cessation. Treatment was effective even in patients with friable conjunctiva following multiple surgical interventions and severe leak, although a longer period was needed for resolution of the bleb leak. The intraocular pressure and visual acuity were largely stable before and after treatment. No side effects or complications arose from this treatment.We recommend a trial of collagen crosslinking on leaking cystic blebs without indications for immediate surgical interventions. It is a relatively easy, non-invasive, pain-free, and potential repeatable procedure for treating leaking cystic blebs, with the aim of strengthening the underlying pathological conjunctiva.
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- 2015
32. The Correlation of Retinal Nerve Fiber Layer Thickness With Blood Pressure in a Chinese Hypertensive Population
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Jacky W. Y. Lee, Jimmy S. M. Lai, RA Gangwani, Rita Sum, Wendy Wing Sze Tsui, Alfred S K Kwong, H.Y. Mo, Jonathan C.H. Chan, and Jenny H. L. Wang
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Adult ,Male ,medicine.medical_specialty ,genetic structures ,Population ,Nerve fiber layer ,Glaucoma ,Observational Study ,Blood Pressure ,Retina ,chemistry.chemical_compound ,Nerve Fibers ,Asian People ,Ophthalmology ,Medicine ,Humans ,Prospective Studies ,education ,Aged ,Aged, 80 and over ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Fundus photography ,Retinal ,General Medicine ,Middle Aged ,medicine.disease ,eye diseases ,Surgery ,medicine.anatomical_structure ,Blood pressure ,chemistry ,Hypertension ,Female ,sense organs ,business ,Research Article - Abstract
To investigate the association between retinal nerve fiber layer (RNFL) thickness and blood pressure (BP) in subjects with systemic hypertension. Subjects with systemic hypertension on anti-hypertensive medications were screened by fundus photography and referred for glaucoma work-up if there was enlarged vertical cup-to-disc (VCDR) ratio ≥0.6, VCDR asymmetry ≥0.2, or optic disc hemorrhage. Workup included a complete ophthalmological examination, Humphrey visual field test, and RNFL thickness measurement by optical coherence tomography. The intraocular pressure (IOP) and RNFL thicknesses (global and quadrant) were averaged from both eyes and the means were correlated with: the systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP) using Pearson correlation. Among 4000 screened hypertensive subjects, 133 were referred for glaucoma workup and 110 completed the workup. Of the 4000 screened subjects, 1.3% had glaucoma (0.9% had normal tension glaucoma [NTG], 0.2% had primary open angle glaucoma, and 0.2% had primary angle closure glaucoma), whereas 0.3% were NTG suspects. The SBP was negatively correlated with the mean superior RNFL thickness (P = 0.01). The DBP was negatively correlated with the mean global (P = 0.03), superior (P = 0.02), and nasal (P = 0.003) RNFL thickness. The MAP was negatively correlated with the mean global (P = 0.01), superior (P = 0.002), and nasal (P = 0.004) RNFL thickness while positively correlated with the mean IOP (P = 0.02). In medically treated hypertensive subjects, glaucoma was present in 1.3%, with NTG being most prevalent. MAP control may help with IOP lowering and RNFL preservation, although future prospective studies will be needed.
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- 2015
33. Comparison of Postoperative Refractive Outcome in Phacotrabeculectomy and Phacoemulsification With Posterior Chamber Intraocular Lens Implantation
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Jimmy S. M. Lai, Jonathan C.H. Chan, and Clement C Y Tham
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Male ,medicine.medical_specialty ,Intraocular pressure ,Biometry ,genetic structures ,Mean squared error ,medicine.medical_treatment ,Glaucoma ,Trabeculectomy ,Spherical equivalent ,Refraction, Ocular ,Cataract ,Lens Implantation, Intraocular ,Posterior chamber intraocular lens implantation ,Approximation error ,Ophthalmology ,medicine ,Humans ,Postoperative Period ,Aged ,Retrospective Studies ,Aged, 80 and over ,Lenses, Intraocular ,Phacoemulsification ,business.industry ,Refractive Errors ,medicine.disease ,Refraction ,Female ,business - Abstract
Purpose: To compare the postoperative refractive outcomes following phacotrabeculectomy and phacoemulsification with posterior chamber intraocular lens implantation. Methods: A retrospective comparative study of 90 consecutive patients (95 eyes) with cataract with or without co-existing glaucoma who had undergone uncomplicated phacotrabeculectomy or phacoemulsification by a single surgeon. The biometry prediction error was determined for each case by the difference between the actual postoperative refraction and the preoperative predicted refractive outcome, in spherical equivalent. This was followed by a comparative analysis of the mean biometry prediction error, and the number of cases with error >0.50 D or 1.00 D. All biometry measurements were performed by one of the two qualified optometrists. Results: The mean and absolute mean biometry prediction error of the 25 eyes that received phacotrabeculectomy (+0.20 D, absolute error 0.96 D) was comparable to the 70 eyes that received phacoemulsification (−0.14 D, absolute error 0.68 D), P = 0.18 (absolute error, P = 0.12). The proportion of cases with prediction error >0.50 D or 1.00 D was 60% or 40% for phacotrabeculectomy, and 44% or 17% for phacoemulsification, respectively. Phacotrabeculectomy was more likely to have a prediction error >1.00 D (P = 0.02) and a myopic shift of >0.50 D or 1.00 D (P = 0.03 or 0.02, respectively). No significant differences were found with regard to the frequency of hyperopic shift or prediction error >0.50 D. There was no significant difference in either the mean error or the frequency of the different types of error for the different biometry operators, types of glaucoma, or postoperative intraocular pressure control success status. Conclusion: Myopically shifted prediction error was significantly more frequent following posterior chamber intraocular lens implantation with phacotrabeculectomy compared with phacoemulsification, even when surgery was uncomplicated and performed by the same surgeon.
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- 2006
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34. The Clinical Outcomes of Cataract Extraction by Phacoemulsification in Eyes With Primary Angle-Closure Glaucoma (PACG) and Co-Existing Cataract
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Clement C Y Tham, Jimmy S. M. Lai, and Jonathan C.H. Chan
- Subjects
Male ,Intraocular pressure ,medicine.medical_specialty ,Visual acuity ,genetic structures ,medicine.medical_treatment ,Visual Acuity ,Glaucoma ,Intraocular lens ,Primary angle-closure glaucoma ,Cataract ,Cataract extraction ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Humans ,Minimally Invasive Surgical Procedures ,Prospective Studies ,Prospective cohort study ,Antihypertensive Agents ,Intraocular Pressure ,Aged ,Aged, 80 and over ,Phacoemulsification ,business.industry ,Middle Aged ,medicine.disease ,Drug Utilization ,eye diseases ,Treatment Outcome ,Female ,sense organs ,medicine.symptom ,Glaucoma, Angle-Closure ,business - Abstract
PURPOSE To evaluate the clinical outcomes of minimally invasive cataract extraction by phacoemulsification, with primary intraocular lens implantation, in eyes with primary angle-closure glaucoma (PACG) and co-existing cataract. MATERIALS AND METHODS Consecutive primary angle-closure glaucoma patients with co-existing visually significant cataract were invited to participate in this prospective study. After obtaining informed consent, cataract extraction by phacoemulsification through a clear corneal incision was performed under topical anesthesia. Foldable intraocular lenses were implanted in the same setting. These patients were then followed up for a minimum of 1 year. Outcome measures included intraocular pressure (IOP), requirement for glaucoma drugs, and visual acuity. RESULTS Twenty-one primary angle-closure glaucoma eyes of 21 patients were recruited. Mean age (+/- SD) was 73.7 +/- 8.1 years (range, 60-87 years). There were 12 female patients and 9 male patients, with 13 right eyes and 8 left eyes. Nine eyes (42.9%) had history of acute primary angle closure. Mean follow-up duration was 20.7 +/- 3.6 months (range, 13-26 months). Intraocular pressure was decreased from a mean preoperative level of 19.7 +/- 6.1 mm Hg (range, 11 mm Hg-40 mm Hg) to 15.5 +/- 3.9 mm Hg (range, 9 mm Hg-26 mm Hg) at final follow-up (P = 0.022) (paired t test). The number of glaucoma eye drops required was decreased from a mean preoperative level of 1.91 +/- 0.77 (range, 1-3) to 0.52 +/- 0.87 (range, 0-3) at final follow-up (P < 0.001) (paired t test). In 10 eyes (47.6%), visual acuity improved significantly after surgery. In 9 eyes (42.9%), visual acuity remained the same. In 2 eyes (9.5%), visual acuity deteriorated significantly after surgery. Mean cup-to-disc ratio was 0.6 +/- 0.2 (range, 0.3-0.9) preoperatively, and 0.7 +/- 0.2 (range, 0.3-0.9) postoperatively (P = 0.047) (paired t test). CONCLUSIONS In primary angle-closure glaucoma patients with co-existing cataract, cataract extraction alone (by phacoemulsification) can significantly reduce both intraocular pressure and the requirement for glaucoma drugs.
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- 2006
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35. Diode Laser Transscleral Cyclophotocoagulation in the Treatment of Chronic Angle-Closure Glaucoma: A Preliminary Study
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Jonathan C.H. Chan, Dennis S.C. Lam, Jimmy S. M. Lai, and Clement C Y Tham
- Subjects
Male ,Reoperation ,Intraocular pressure ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Visual Acuity ,Glaucoma ,Pilot Projects ,Pupil ,law.invention ,Quadrant (abdomen) ,law ,Ophthalmology ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Intraocular Pressure ,Aged ,Laser Coagulation ,business.industry ,Ciliary Body ,Middle Aged ,medicine.disease ,Laser ,eye diseases ,Treatment Outcome ,Chronic angle-closure glaucoma ,Chronic Disease ,Female ,sense organs ,Ophthalmic Solutions ,medicine.symptom ,Glaucoma, Angle-Closure ,business - Abstract
PURPOSE To evaluate the efficacy and safety of diode laser transscleral cyclophotocoagulation in the treatment of chronic angle-closure glaucoma. PATIENTS AND METHODS A prospective, non-comparative interventional pilot study was conducted. Fourteen eyes of 14 Chinese patients with chronic angle-closure glaucoma whose intraocular pressures were greater than 21 mm Hg on medications were treated with diode laser transscleral cyclophotocoagulation using the G-probe at the United Christian Hospital between February 2000 and May 2001. The inferior 270 degrees quadrant (from 2 to 11 o'clock for right eye and from 1 to 10 o'clock for left eye) was treated and the patients were followed up regularly. The initial laser energy was set at 2,000 mWatt with a duration of 2 seconds. The post-treatment anti-glaucoma medications were adjusted according to the intraocular pressure. If medications failed to lower the intraocular pressure to below 21 mm Hg, cyclophotocoagulation to the same inferior 270 degrees quadrant was repeated. RESULTS All patients completed a 12-month follow-up period. The total success rate defined as IOP < 21 mm Hg with or without medication(s) was 85.7% at 1 year of follow-up review. The mean +/- SD intraocular pressure decreased from pre-treatment level of 36.9 +/- 11.7 mm Hg to 18.9 +/- 6.5 mm Hg at 1 year after treatment. The difference was statistically significant (P < 0.001) (Paired t test). The mean +/- SD number of IOP-lowering eyedrops was significantly reduced from 1.9 +/- 0.7 before cyclophotocoagulation to 0.4 +/- 0.8 at 1 year after treatment (P = 0.0002) (Paired t test). Two eyes required repeat treatment. Seven eyes (50%) had atonic pupil following the laser treatment. CONCLUSION Diode laser transscleral cyclophotocoagulation is effective in lowering the intraocular pressure in chronic angle-closure glaucoma and its effect lasts for at least 1 year.
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- 2003
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36. Glaucoma Drainage Device Tube Retraction and Blockage in a Patient with Iridocorneal Endothelial Syndrome Treated With Nd:YAG Membranectomy
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Jonathan C.H. Chan, Jimmy S. M. Lai, Bonnie Nga Kwan Choy, and Carol Pui Yang Chien
- Subjects
medicine.medical_specialty ,Intraocular pressure ,genetic structures ,medicine.diagnostic_test ,business.industry ,Lumen (anatomy) ,Timolol ,medicine.disease ,Glaucoma valve ,eye diseases ,Surgery ,Iridocorneal endothelial syndrome ,Ophthalmology ,Occlusion ,Gonioscopy ,Medicine ,sense organs ,business ,Complication ,medicine.drug - Abstract
Purpose: To report on a case that demonstrates the successful treatment of tube blockage of the Ahmed Glaucoma Valve at its aqueous entry site by Nd:YAG laser membranectomy. Method: We report a case of refractory intraocular pressure elevation in a patient with iridocorneal endothelial syndrome after glaucoma drainage device due to blocked tube from the iridocorneal endothelial syndrome membrane. In July 2014, our patient presented with sudden right eye elevated intraocular pressure to 67 mmHg despite a well-controlled intraocular pressure in the range of teens with timolol alone over the last 2 years. Gonioscopy showed total synechial angle closure and increasing her medical treatment failed to control the intraocular pressure. Ahmed glaucoma valve was implanted successfully. However, recurrence of raised intraocular pressure from partial tube retraction and tube blockage at its aqueous entry site by an endothelial membrane was noted at 2 weeks after the surgery. Nd:YAG laser membranectomy was performed on 2 occasions to restore the patency of the tube shunt. After the second laser membranectomy, the patient’s intraocular pressure returned to, and remained at, normal level since. Conclusion: Tube occlusion by membrane is a well-known complication following glaucoma drainage device tube in patients with iridocorneal endothelial syndrome. Nd:YAG membranectomy is effective to restore the patency of tube lumen without subjecting patients to more invasive surgical interventions including tube extender or another glaucoma drainage device. However, more studies are required to ascertain the long term effect of laser membranectomy to a blocked tube, in comparison to other treatment modalities. To our knowledge, this is the first reported case of using laser membranectomy alone in treating Ahmed glaucoma valve tube obstruction due to a retracted tube blocked by endothelial membrane.
- Published
- 2015
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37. Twenty-four-hour intraocular pressure related changes following adjuvant selective laser trabeculoplasty for normal tension glaucoma
- Author
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Jacky W. Y. Lee, Jimmy S. M. Lai, Lin Fu, and Jonathan C.H. Chan
- Subjects
Male ,medicine.medical_specialty ,Intraocular pressure ,Selective laser trabeculoplasty ,genetic structures ,Contact Lenses ,medicine.medical_treatment ,Glaucoma ,Monitoring, Ambulatory ,Observational Study ,Trabeculectomy ,Article ,Normal tension glaucoma ,Ophthalmology ,Glaucoma surgery ,Medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Perioperative Period ,Intraocular Pressure ,Aged ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Contact lens ,Treatment Outcome ,Female ,Laser Therapy ,business - Abstract
To investigate intraocular pressure (IOP) related patterns before and after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG). In this prospective cohort study, 18 NTG patients underwent SLT. Success was defined as IOP reduction ≥20% by Goldmann applanation tonometry. 24-hour IOP-related pattern recording with a contact lens sensor (CLS) (SENSIMED Triggerfish®, Sensimed, Switzerland) was done before (baseline) and 1 month after SLT. A cosine function was fitted to the mean CLS patterns for each individual in the SLT success and non-success groups and the amplitude before and after SLT was calculated. Diurnal, nocturnal, and 24-hour CLS pattern local variability was determined for pre- and post-SLT sessions. Cosine amplitude and variability were compared before and after SLT by group using paired t-tests, with α = 0.05. Patients (11 women, 7 men) had a mean age of 65.1 ± 13.7 years. Mean IOP was 15.3 ± 2.2 mm Hg at baseline and was reduced by 17.0% to 12.7 ± 1.8 mm Hg 1 month after SLT (P = 0.001). SLT was successful in 8 patients (44%). The amplitude of the fitted cosine was reduced by 24.6% in the success group, but displayed an amplitude increase of 19.2% post-SLT in the non-success group. Higher diurnal local variability of the CLS pattern was observed after SLT in non-success subjects (P = 0.002), while nocturnal variability showed no significant change. The increase in diurnal variability in the non-success group led to an increase in 24-hour variability in this group (P = 0.001). No change in local variability (diurnal, nocturnal, and 24-hour) was seen in the success group. The IOP-related pattern cosinor amplitude was reduced in NTG patients with a successful SLT treatment whereas the non-success group exhibited an increase of cosine amplitude. Higher diurnal and 24-hour CLS pattern variability was observed in non-success patients 1 month post-SLT.
- Published
- 2014
38. Differences in corneal parameters between normal tension glaucoma and primary open-angle glaucoma
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Raymond Wong, Jonathan C.H. Chan, Ian Y. H. Wong, Jimmy S. M. Lai, and Jacky W. Y. Lee
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Male ,Intraocular pressure ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Open angle glaucoma ,Gonioscopy ,Visual Acuity ,Glaucoma ,Spherical equivalent ,Cell Count ,Cornea ,chemistry.chemical_compound ,Tonometry, Ocular ,Normal tension glaucoma ,Ophthalmology ,medicine ,Humans ,Low Tension Glaucoma ,Intraocular Pressure ,Aged ,Retrospective Studies ,business.industry ,Endothelium, Corneal ,Corneal Topography ,Retinal ,Middle Aged ,medicine.disease ,eye diseases ,Visual field ,Cross-Sectional Studies ,chemistry ,Female ,sense organs ,medicine.symptom ,Visual Fields ,business ,Glaucoma, Open-Angle ,Tomography, Optical Coherence ,Follow-Up Studies - Abstract
The purpose of this study was to identify the differences in corneal parameters between medically treated normal tension glaucoma (NTG) and primary open-angle glaucoma (POAG) subjects. This cross-sectional study from September 2011 to September 2012 included consecutive subjects with POAG and NTG who were receiving topical anti-glaucoma medications at the time of the study. Subjects were excluded if they had pre-existing corneal pathology or scars and previous glaucoma lasers. The following parameters were compared between the NTG and POAG groups: endothelial cell count, central corneal thickness (CCT), spherical equivalent, presenting and current intraocular pressure (IOP), number and type of anti-glaucoma medication, retinal nerve fibre layer thickness, visual field index, visual acuity, and phakic status. Only the right eye was used for statistical analysis. The right eye of the 30 NTG and 28 POAG subjects had comparable baseline characteristics, post-treatment IOP, and glaucoma severity. The endothelial cell count was significantly lower in the NTG versus the POAG group (2,380.0 ± 315.4 vs. 2,530.0 ± 320.4 cells/mm(2), p = 0.04). There were no significant differences in the spherical equivalent or CCT between the NTG and POAG groups. A significantly lower corneal endothelial cell count was found in NTG compared to POAG.
- Published
- 2014
39. The association between clinical parameters and glaucoma-specific quality of life in Chinese primary open-angle glaucoma patients
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Jacky W. Y. Lee, Q Li, Jimmy S. M. Lai, Catherine W S Chan, and Jonathan C.H. Chan
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Male ,medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,Open angle glaucoma ,Cross-sectional study ,Visual Acuity ,Glaucoma ,Nerve Fibers ,Quality of life ,Statistical significance ,Ophthalmology ,Surveys and Questionnaires ,Medicine ,Humans ,Intraocular Pressure ,Aged ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,eye diseases ,Visual field ,Cross-Sectional Studies ,Quality of Life ,Optometry ,Hong Kong ,Female ,sense organs ,medicine.symptom ,Visual Fields ,business ,Glaucoma, Open-Angle ,Tomography, Optical Coherence - Abstract
OBJECTIVE. To investigate the association between clinical measurements and glaucoma-specific quality of life in Chinese glaucoma patients. DESIGN. Cross-sectional study. SETTING. An academic hospital in Hong Kong. PATIENTS. A Chinese translation of the Glaucoma Quality of Life-15 questionnaire was completed by 51 consecutive patients with bilateral primary open-angle glaucoma. The binocular means of several clinical measurements were correlated with Glaucoma Quality of Life-15 findings using Pearson's correlation coefficient and linear regression. The measurements were the visual field index and pattern standard deviation from the Humphrey Field Analyzer, Snellen best-corrected visual acuity, presenting intra-ocular pressure, current intra-ocular pressure, average retinal nerve fibre layer thickness via optical coherence tomography, and the number of topical anti-glaucoma medications being used. RESULTS. In these patients, there was a significant correlation and linear relationship between a poorer Glaucoma Quality of Life-15 score and a lower visual field index (r=0.3, r(2)=0.1, P=0.01) and visual acuity (r=0.3, r(2)=0.1, P=0.03). A thinner retinal nerve fibre layer also correlated with a poorer Glaucoma Quality of Life-15 score, but did not attain statistical significance (r=0.3, P=0.07). There were no statistically significant correlations for the other clinical parameters with the Glaucoma Quality of Life-15 scores (all P values being >0.7). The three most problematic activities affecting quality of life were "adjusting to bright lights", "going from a light to a dark room or vice versa", and "seeing at night". CONCLUSION. For Chinese primary open-angle glaucoma patients, binocular visual field index and visual acuity correlated linearly with glaucoma-specific quality of life, and activities involving dark adaptation were the most problematic.
- Published
- 2014
40. Consensual ophthalmotonic reaction in Chinese patients following augmented trabeculectomy or ExPRESS shunt implantation
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Jonathan C.H. Chan, Wing Lau Ho, Jennifer W. H. Shum, Jimmy S. M. Lai, and Bonnie Nga Kwan Choy
- Subjects
Male ,Intraocular pressure ,medicine.medical_specialty ,genetic structures ,medicine.medical_treatment ,Observational Study ,Glaucoma ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Glaucoma surgery ,Humans ,Trabeculectomy ,Postoperative Period ,Intraocular Pressure ,Retrospective Studies ,ExPRESS shunt ,Chinese population ,business.industry ,trabeculectomy ,Retrospective cohort study ,General Medicine ,Middle Aged ,medicine.disease ,Laser trabeculoplasty ,consensual ophthalmotonic reaction ,eye diseases ,Surgery ,Filtration surgery ,glaucoma surgery ,030221 ophthalmology & optometry ,Hong Kong ,Female ,sense organs ,business ,030217 neurology & neurosurgery ,Research Article - Abstract
Introduction: Consensual ophthalmotonic reaction (COR) was first described in 1924. Studies following monocular application of glaucoma drops and laser trabeculoplasty showed a drop in fellow eye intraocular pressure (IOP). However, studies following monocular surgery showed heterogeneous results. The purpose of this study was to investigate the COR in Chinese patients who have received monocular filtration surgery. Methods: A noncomparative retrospective study of 65 eyes undergoing filtration surgery in Queen Mary Hospital was conducted. The IOP was obtained at baseline and postoperative days 1, 3, 7 and 14. Patient's age, sex, type of glaucoma and surgery, preoperative medications, postoperative bleb status, and number of interventions were tabulated. The postoperative IOP measurements over both eyes were obtained, and the readings were averaged to decrease the chances of extreme readings being a one-off event and allow for regression to the mean bias. Results: COR was observed in the unoperated fellow eye. The mean preoperative IOP and averaged postoperative IOP were 17.2 ± 5.2 mm Hg and 20.1 ± 8.9 mm Hg, respectively (P 30% from baseline, while none showed IOP drop >30% from baseline. Discussion: Following monocular penetrating filtration surgery, our Chinese population demonstrated a significant fellow eye IOP increase in the early postoperative period. We should bear in mind the influence of COR and take care to measure the fellow eye IOP following monocular surgery.
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- 2016
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41. Phacoemulsification vs phacotrabeculectomy in chronic angle-closure glaucoma with cataract: complications [corrected]
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Jonathan C.H. Chan, Dennis S.C. Lam, Sze Wing Lam, Thomas Y. H. Chiu, Yolanda Y.Y. Kwong, Clement C Y Tham, Felix C.H. Li, Dexter Y L Leung, and Jimmy S. M. Lai
- Subjects
Male ,medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,Eye disease ,medicine.medical_treatment ,Visual Acuity ,Glaucoma ,Trabeculectomy ,Cataract ,law.invention ,Postoperative Complications ,Randomized controlled trial ,law ,Ophthalmology ,medicine ,Humans ,Intraoperative Complications ,Intraocular Pressure ,Aged ,Aged, 80 and over ,Phacoemulsification ,business.industry ,Middle Aged ,medicine.disease ,eye diseases ,Surgery ,Treatment Outcome ,Chronic angle-closure glaucoma ,Chronic Disease ,Disease Progression ,Female ,sense organs ,medicine.symptom ,Complication ,business ,Glaucoma, Angle-Closure - Abstract
OBJECTIVE To compare the complications of phacoemulsification alone vs combined phacotrabeculectomy in chronic angle-closure glaucoma (CACG) with coexisting cataract. METHODS Patients with CACG with coexisting cataract recruited into 2 randomized controlled trials comparing phacoemulsification alone vs combined phacotrabeculectomy were pooled for analysis. The first trial recruited patients with medically controlled intraocular pressure, while the second trial recruited patients with medically uncontrolled intraocular pressure. The 2 trials had otherwise identical study designs. All patients were reviewed every 3 months for 2 years after surgery. The main outcome measure was the surgical complications of phacoemulsification alone vs combined phacotrabeculectomy in CACG eyes with cataract. RESULTS One hundred twenty-three CACG eyes with cataract from 123 patients were included. Sixty-two CACG eyes were randomized to receive phacoemulsification alone, and 61 eyes had combined phacotrabeculectomy. In the phacoemulsification group, 5 of the 62 CACG eyes (8.1%) had a total of 5 surgical complications. In the combined phacotrabeculectomy group, 16 of the 61 CACG eyes (26.2%) had a total of 19 surgical complications. The difference in the proportion of eyes with 1 or more surgical complications between the 2 treatment groups was statistically significant (P = .007, Pearson chi(2) test). There was no statistically significant difference in final visual acuity or glaucomatous progression during the 24-month follow-up. CONCLUSIONS Combined phacotrabeculectomy resulted in significantly more surgical complications than phacoemulsification alone in CACG eyes with coexisting cataract. There was no difference in visual acuity or disease progression between the 2 treatment groups.
- Published
- 2010
42. Systemic effects of inflammation in bronchiectasis
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Wah-Kit Lam, Mary S. Ip, E. Liong, and Jonathan C.H. Chan
- Subjects
Adult ,Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Adolescent ,Globulin ,Serum albumin ,Immunoglobulins ,Alpha (ethology) ,Inflammation ,Gastroenterology ,Leukocyte Count ,Forced Expiratory Volume ,Internal medicine ,medicine ,Humans ,Inverse correlation ,Lung ,Serum Albumin ,Aged ,Bronchiectasis ,biology ,business.industry ,Respiratory disease ,Middle Aged ,medicine.disease ,Peripheral ,alpha 1-Antitrypsin ,Immunology ,biology.protein ,Female ,Serum Globulins ,medicine.symptom ,business - Abstract
A group of bronchiectatic subjects in the clinically stable state were studied for systemic evidence of inflammation. The following parameters were evaluated: body weight, serum albumin, serum globulin, serum alpha 1-antitrypsin (alpha 1 AT) and peripheral white cell count. For serum albumin and globulin, comparison was made between subjects with bronchiectasis and control subjects with no known pulmonary disease matched for sex and age, and for serum alpha 1 AT and peripheral white cell count, matched for smoking habit as well. The bronchiectatic subjects showed systemic effects of inflammation as indicated by lower body weight and serum albumin (P less than 0.01), higher serum globulin (P less than 0.001), serum alpha 1 AT (P less than 0.05) and total leucocyte count (P less than 0.05). Differential white cell count showed that the elevation was distributed in most cell types. Correlation matrix was done for the above systemic parameters and indices of airway inflammation including sputum volume, purulence, and polymorph count and FEV1. There was an inverse correlation between total peripheral WBC count and FEV1 in percentage of predicted (P less than 0.01), and a positive correlation between sputum purulence and sputum polymorph score (P less than 0.05). This suggests that host peripheral leucocyte response may be a factor in the determination of lung function.
- Published
- 1991
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43. Phacoemulsification versus combined phacotrabeculectomy in medically uncontrolled chronic angle closure glaucoma with cataracts
- Author
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Clement C.Y. Tham, Yolanda Y.Y. Kwong, Dexter Y.L. Leung, S.W. Lam, Felix C.H. Li, Thomas Y.H. Chiu, Jonathan C.H. Chan, Dennis S.C. Lam, and Jimmy S.M. Lai
- Subjects
Aged, 80 and over ,Male ,Alkylating Agents ,Phacoemulsification ,Mitomycin ,Visual Acuity ,Trabeculectomy ,Middle Aged ,Cataract ,Ophthalmology ,Tonometry, Ocular ,Postoperative Complications ,Treatment Outcome ,Lens Implantation, Intraocular ,Chronic Disease ,Humans ,Female ,Prospective Studies ,Glaucoma, Angle-Closure ,Antihypertensive Agents ,Intraocular Pressure ,Aged ,Follow-Up Studies - Abstract
To compare phacoemulsification alone versus combined phacotrabeculectomy in medically uncontrolled chronic angle closure glaucoma (CACG) with coexisting cataract.Prospective randomized clinical trial.Fifty-one medically uncontrolled CACG eyes with coexisting cataract of 51 patients.Recruited patients were randomized into group 1 (phacoemulsification alone) or group 2 (combined phacotrabeculectomy with adjunctive mitomycin C). Postoperatively, patients were reviewed every 3 months for 2 years.Intraocular pressure (IOP) and requirement for topical glaucoma drugs.Twenty-seven CACG eyes were randomized into group 1, and 24 CACG eyes were randomized into group 2. Combined phacotrabeculectomy resulted in lower mean postoperative IOP than phacoemulsification alone at 3 months (14.0 vs. 17.0 mmHg, P = 0.01), 15 months (13.2 vs. 15.4 mmHg, P = 0.02), and 18 months (13.6 vs. 15.9 mmHg, P = 0.01). Combined phacotrabeculectomy resulted in 1.25 fewer topical glaucoma drugs (P0.001) in the 24-month postoperative period, compared with phacoemulsification alone. Combined surgery was associated with more postoperative complications (P0.001) and more progression of optic neuropathy (P = 0.03), compared with phacoemulsification alone.Combined phacotrabeculectomy with adjunctive mitomycin C is more effective than phacoemulsification alone in controlling IOP in medically uncontrolled CACG eyes with coexisting cataract. Combined phacotrabeculectomy is associated with more postoperative complications.
- Published
- 2008
44. Correlation of previous acute angle-closure attack with extent of synechial angle closure in chronic primary angle-closure glaucoma patients
- Author
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Jimmy S. M. Lai, Clement C Y Tham, Thomas Y. H. Chiu, Yolanda Y.Y. Kwong, S W Lam, Jonathan C.H. Chan, and Dennis S.C. Lam
- Subjects
Male ,medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,Acute angle ,Eye disease ,Optic Disk ,Closure (topology) ,Visual Acuity ,Glaucoma ,Chronic primary angle closure glaucoma ,Medicine ,Humans ,Intraocular Pressure ,Aged ,Aged, 80 and over ,business.industry ,Acute glaucoma ,Middle Aged ,medicine.disease ,eye diseases ,Surgery ,Ophthalmology ,Acute Disease ,Chronic Disease ,Female ,medicine.symptom ,business ,Glaucoma, Angle-Closure - Abstract
To document any correlation between previous acute angle-closure attack and the extent of synechial angle closure in chronic primary angle-closure glaucoma (PACG) patients.Consecutive cases of chronic PACG with patent peripheral iridotomy had gonioscopy performed. The extents of synechial angle closure of those chronic PACG eyes with previous documented acute angle-closure attack were compared to those eyes without such a history.A total of 102 chronic PACG eyes of 102 patients were recruited. Twenty-seven eyes (26.5%) had a previous documented acute angle closure, while 75 eyes (73.5%) did not. The mean extent of synechial angle closure +/-1 SD was 307+/-68 degrees (range, 150-360 degrees) in those chronic PACG eyes with a history of previous acute angle closure, compared to 266+/-89 degrees (range, 90-360 degrees) in those chronic PACG eyes without such a history (P=0.03, Student's t-test). There were no statistically significant differences between the two groups in age, LogMAR visual acuity, intraocular pressure (IOP), number of glaucoma eye drops, vertical cup-to-disk ratio, mean deviation or pattern SD in Humphrey automated perimetry, and anterior chamber depth (P0.05).Previous acute angle-closure attack correlated with more extensive synechial angle closure in chronic PACG patients in this study.
- Published
- 2008
45. Two-Year Clinical Results After Selective Laser Trabeculoplasty for Normal Tension Glaucoma
- Author
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Jacky W. Y. Lee, Jonathan C.H. Chan, Jennifer Wh Shum, and Jimmy S. M. Lai
- Subjects
Male ,Intraocular pressure ,medicine.medical_specialty ,genetic structures ,Selective laser trabeculoplasty ,medicine.medical_treatment ,Observational Study ,Trabeculectomy ,Laser therapy ,Normal tension glaucoma ,Ophthalmology ,Glaucoma surgery ,medicine ,Humans ,Low Tension Glaucoma ,Prospective Studies ,Prospective cohort study ,Intraocular Pressure ,Aged ,business.industry ,General Medicine ,Middle Aged ,eye diseases ,Female ,Laser Therapy ,sense organs ,business ,Research Article - Abstract
This article aims to investigate the clinical results at 2 years after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG). This prospective cohort study recruited NTG patients taking antiglaucoma medication. Subjects were excluded if they had previous glaucoma surgery/laser or corneal pathologies. All subjects underwent a 1-month washout. A single session of SLT was performed to 360° of the trabecular meshwork. Medication was resumed at 1 month to achieve a targeted 30% intraocular pressure (IOP) reduction from the post-washout/pre-SLT IOP. IOP was measured every 3 months and medication use was recorded at 3, 6, 12, and 24 months. Subjects with a secondary SLT or cataract extraction were excluded from IOP and medication analyses. At 24 months, 34 of the initial 45 right eyes were eligible for analyses. There were significant IOP reductions at all time intervals (except at 1 week) following SLT when compared to the prestudy (without medication) or pre-SLT (post-washout) IOP (P 20% from pre-SLT, without medication) was achieved in 11.1% (5/45). Reductions in IOP and medication use were evident at 2 years following SLT for the treatment of NTG whereas 11% remained medication free. Trial Registrations: The Clinical Trials Register of the University of Hong Kong HKCTR1847. The European Clinical Trials Database 2014-003305-15 (August 11, 2014).
- Published
- 2015
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46. To compare argon laser peripheral iridoplasty (ALPI) against systemic medications in treatment of acute primary angle-closure: mid-term results
- Author
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Jonathan C.H. Chan, Dennis S.C. Lam, Clement C Y Tham, S W Lam, Agnes S. Y. Poon, Jimmy S. M. Lai, and John K. H. Chua
- Subjects
Male ,Intraocular pressure ,medicine.medical_specialty ,Iridectomy ,genetic structures ,medicine.medical_treatment ,Eye disease ,Mid term results ,Visual Acuity ,Glaucoma ,Ophthalmology ,medicine ,Humans ,Mannitol ,Prospective Studies ,Antihypertensive Agents ,Aged ,Laser peripheral iridoplasty ,Aged, 80 and over ,Chemotherapy ,Medical treatment ,business.industry ,Treatment options ,Middle Aged ,medicine.disease ,eye diseases ,Acetazolamide ,Treatment Outcome ,Acute Disease ,Drug Therapy, Combination ,Female ,sense organs ,Laser Therapy ,business ,Glaucoma, Angle-Closure ,Follow-Up Studies - Abstract
To compare the clinical outcome of argon laser peripheral iridoplasty (ALPI) against systemic medications in treatment of acute primary angle-closure (APAC).Consecutive patients with APAC were recruited and randomized to receive one of two treatment options: immediate ALPI or systemic acetazolamide +/- mannitol. All eyes were followed up for at least 6 months after laser iridotomy. Main outcome measures were intraocular pressure (IOP) and requirement for glaucoma medications.A total of 41 eyes (39 patients) were randomized into the ALPI group, and 38 eyes (32 patients) into the medical treatment group. There were no significant differences between the two groups in sex, age, presenting IOP, and duration of attack. Mean follow-up duration +/- SD was 15.7 +/- 5.8 months. There were no significant differences between the two groups in mean final IOP and requirement for glaucoma medications.There were no statistically significant differences in mean IOP and requirement for glaucoma drugs between APAC eyes treated with ALPI and systemic medications.
- Published
- 2005
47. Immediate argon laser peripheral iridoplasty (ALPI) as initial treatment for acute phacomorphic angle-closure (phacomorphic glaucoma) before cataract extraction: a preliminary study
- Author
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S W Lam, John K. H. Chua, Agnes S. Y. Poon, Clement C Y Tham, Jonathan C.H. Chan, Dennis S.C. Lam, and Jimmy S. M. Lai
- Subjects
Male ,medicine.medical_specialty ,Intraocular pressure ,genetic structures ,medicine.medical_treatment ,Eye disease ,Glaucoma ,Timolol ,Iris ,Pilot Projects ,Phacomorphic glaucoma ,Cataract ,Ophthalmology ,medicine ,Humans ,Aged ,Laser peripheral iridoplasty ,Aged, 80 and over ,Phacoemulsification ,business.industry ,Middle Aged ,medicine.disease ,eye diseases ,Acute Disease ,Female ,sense organs ,Laser Therapy ,business ,Acetazolamide ,Glaucoma, Angle-Closure ,medicine.drug - Abstract
To study the safety and efficacy of immediate argon laser peripheral iridoplasty (ALPI) as initial treatment of acute phacomorphic angle-closure (phacomorphic glaucoma) before cataract extraction.In all, 10 consecutive patients with acute phacomorphic angle-closure and intraocular pressure (IOP)or =40 mmHg were recruited into the study. Each patient received topical atropine (1%) and timolol (0.5%), and immediate ALPI as initial treatment. The IOP at 15, 30, 60, and 120 min, and then 1 day, after ALPI were documented by applanation tonometry. Systemic IOP-lowering drugs were only started if IOP remained above 40 mmHg at 2 h after ALPI. Cataract extraction was subsequently performed as definitive treatment.In total, 10 patients (five male, five female), with a mean age+/-SD of 73.1+/-10.3 years were recruited. Mean duration of symptomatic attack was 128+/-232 h. After ALPI, the mean IOP was reduced from 56.1+/-12.5 to 45.3+/-14.5 mmHg at 15 min, 37.6+/-7.5 mmHg at 30 min, 34.2+/-9.7 mmHg at 60 min, 25.5+/-8.7 mmHg at 120 min, and 13.6+/-4.2 mmHg at 1 day. In one patient, systemic acetazolamide was administered, because the IOP remained above 40 mmHg at 2 h after ALPI. All 10 patients had uncomplicated cataract extraction performed within 4 days after ALPI. No complications from the laser procedure were encountered.Immediate ALPI, replacing systemic antiglaucomatous medications, appeared to be safe and effective as first-line treatment of acute phacomorphic angle-closure.
- Published
- 2004
48. Scanning laser polarimetry in patients with acute attack of primary angle closure
- Author
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Clement C Y Tham, Jane C.C. Yeung, Jonathan C.H. Chan, Dennis S.C. Lam, Nelson K.F Yip, Jimmy S. M. Lai, Patrick S. H. Li, and Wilson W. T. Tang
- Subjects
Male ,medicine.medical_specialty ,Time Factors ,genetic structures ,Eye disease ,Nerve fiber layer ,Scanning laser polarimetry ,Nerve fiber ,Retina ,chemistry.chemical_compound ,Nerve Fibers ,Optic Nerve Diseases ,Medicine ,Humans ,In patient ,Intraocular Pressure ,Aged ,Birefringence ,Microscopy, Confocal ,business.industry ,Significant difference ,Retinal ,General Medicine ,Middle Aged ,medicine.disease ,eye diseases ,Surgery ,Ophthalmology ,medicine.anatomical_structure ,chemistry ,Acute Disease ,Female ,sense organs ,business ,Glaucoma, Angle-Closure - Abstract
Purpose To compare the retinal nerve fiber layer measurements of attacked eyes with their fellow eyes after a single unilateral attack of acute primary angle closure (APAC). Methods Patients with a single episode of APAC in 1 eye, successfully treated with laser peripheral iridotomy, were recruited. Eyes with persistently raised intraocular pressure (IOP) after resolution of the acute attack were excluded. Scanning laser polarimetry was carried out at 6 months after remission of the acute attack. The various parameters between the attacked and the fellow eyes were compared using the Student t-test. Results Twenty-six patients (24 female and 2 male, mean age 66.9±8.1 years) were recruited. The duration of the APAC ranged from 5 to 98 hours (mean, 36.3 hours). The mean presenting IOP during the acute attack was 62.0±9.4 mm Hg. Only the mean inferior ratio and the ellipse modulation showed a statistically significant difference between the attacked and the fellow eyes among the 12 standard scanning laser polarimetry measurement parameters. Conclusion No severe retinal nerve fiber layer damage was documented in eyes that suffered a single episode of APAC with duration of attack up to 48 hours. With duration of attack longer than 48 hours, retinal nerve fiber layer damage was detected.
- Published
- 2003
49. Phacotrabeculectomy in treatment of primary angle-closure glaucoma and primary open-angle glaucoma
- Author
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Clement C Y Tham, Jimmy S. M. Lai, Jonathan C.H. Chan, and Dennis S.C. Lam
- Subjects
Male ,Intraocular pressure ,medicine.medical_specialty ,genetic structures ,Open angle glaucoma ,medicine.medical_treatment ,Glaucoma ,Trabeculectomy ,Primary angle-closure glaucoma ,Cataract ,Lens Implantation, Intraocular ,Posterior chamber intraocular lens implantation ,Ophthalmology ,Medicine ,Humans ,In patient ,Intraocular Pressure ,Aged ,Retrospective Studies ,Phacoemulsification ,business.industry ,General Medicine ,medicine.disease ,eye diseases ,Treatment Outcome ,Female ,sense organs ,business ,Glaucoma, Angle-Closure ,Glaucoma, Open-Angle - Abstract
To evaluate the surgical outcome of combined phacoemulsification, posterior chamber intraocular lens implantation, and trabeculectomy (phacotrabeculectomy) in patients with primary angle-closure glaucoma (PACG) or primary open-angle glaucoma (POAG).The records of 57 consecutive patients (65 eyes) with PACG or POAG that were treated with phacotrabeculectomy were reviewed retrospectively. There were 31 eyes with PACG and 34 with POAG. The mean follow-up period was 21.0 +/- 8.3 months. The visual acuity, intraocular pressure (IOP), number of medications, and complications were evaluated.The mean IOP and the number of glaucoma medications decreased significantly after phacotrabeculectomy in both groups. The mean IOP reduction was significantly greater in eyes with PACG (P0.05). The absolute success rates were 87.1% and 70.6% in PACG and POAG, respectively. The difference in the success rates was not significant (P = 0.297). The early postoperative complication rates were similar in both groups.Phacotrabeculectomy results in greater IOP reduction in eyes with PACG than in those with POAG, but the overall success rates were not significantly different.
- Published
- 2003
50. Arsenic trioxide in comparison with chemotherapy and bone marrow transplantation for the treatment of relapsed acute promyelocytic leukaemia
- Author
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Jonathan C.H. Chan, CH Chan, A K W Lie, YM Yeung, C. S. Chim, S. Y. Liu, Y. K. Mak, S. K. Ma, Y. T. Chen, Sze-Fai Yip, W. Y. Au, R. Liang, C. C. So, Yok-Lam Kwong, and L. G. Wong
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Gastroenterology ,Arsenicals ,chemistry.chemical_compound ,Arsenic Trioxide ,Leukemia, Promyelocytic, Acute ,Internal medicine ,medicine ,Secondary Prevention ,Humans ,Arsenic trioxide ,Child ,Survival rate ,Bone Marrow Transplantation ,Retrospective Studies ,Chemotherapy ,business.industry ,Retrospective cohort study ,Oxides ,Hematology ,Immunotherapy ,Middle Aged ,medicine.disease ,Surgery ,Clinical trial ,Survival Rate ,Leukemia ,Regimen ,Oncology ,chemistry ,Female ,business - Abstract
Background The best overall treatment strategy for patients with acute promyelocytic leukaemia (APL) in relapse with chemotherapy, bone marrow transplantation (BMT) or arsenic trioxide (As(2)O(3)) based therapy remains undefined. Patients and methods We reviewed the clinical course and treatment outcome of 143 APL cases seen in four major hospitals in Hong Kong over a 10-year period. Results Complete remission (CR) was attained in 113 cases (79%) with all-trans retinoic acid (ATRA) and chemotherapy. Relapse occurred at a median of 16 months in 54 cases, with a 3-year disease free survival of 56%. Post-relapse treatment was successful in 41 cases (76%), giving an actuarial 3-year overall survival (OS) of 81% from CR1. Three different protocols were used: chemotherapy alone (n = 19), allogeneic BMT (n = 14) and an As(2)O(3)-based regimen (n = 21). Chemotherapy was associated with the highest treatment-related mortality (TRM) at 53%, giving a CR2 rate of 47%. TRM was 36% for BMT. The CR2 rate for the As(2)O(3)-based regimen was 100%, with no TRM. However, 38% of As(2)O(3) treated patients had subsequent relapses, which were further salvaged in 75% by combined As(2)O(3) plus ATRA. The actuarial OS for the three protocols leveled off by 2 years at 82% for As(2)O(3), 43% for BMT and 23% for chemotherapy (P = 0.0004). Conclusions Our results suggest that As(2)O(3) may be superior to chemotherapy and BMT for the treatment of APL in relapse.
- Published
- 2003
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