25 results on '"Prin Rojanapongpun"'
Search Results
2. Digital Gonioscopy Based on Three-dimensional Anterior-Segment OCT
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Prin Rojanapongpun, Tin A. Tun, Yifan Yang, Rouxi Zhou, Tin Aung, Visanee Tantisevi, Zhen Qiu, Xu Sun, Jian Xiong, Yu Chen, Weijing Cheng, Anita Manassakorn, Shihao Zhang, Yanwu Xu, Yuhong Liu, Fengbin Lin, Fei Li, Xiulan Zhang, Daniel S W Ting, Monisha E. Nongpiur, Baskaran Mani, Sunee Chansangpetch, Kitiya Ratanawongphaibul, and Mingkui Tan
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Glaucoma ,Narrow angle ,Eye care ,medicine.disease ,Ophthalmology ,medicine.anatomical_structure ,Multicenter study ,medicine ,Gonioscopy ,Trabecular meshwork ,Internal validation ,business ,Peripheral anterior synechiae - Abstract
Purpose To develop and evaluate the performance of a 3-dimensional (3D) deep-learning–based automated digital gonioscopy system (DGS) in detecting 2 major characteristics in eyes with suspected primary angle-closure glaucoma (PACG): (1) narrow iridocorneal angles (static gonioscopy, Task I) and (2) peripheral anterior synechiae (PAS) (dynamic gonioscopy, Task II) on OCT scans. Design International, cross-sectional, multicenter study. Participants A total of 1.112 million images of 8694 volume scans (2294 patients) from 3 centers were included in this study (Task I, training/internal validation/external testing: 4515, 1101, and 2222 volume scans, respectively; Task II, training/internal validation/external testing: 378, 376, and 102 volume scans, respectively). Methods For Task I, a narrow angle was defined as an eye in which the posterior pigmented trabecular meshwork was not visible in more than 180° without indentation in the primary position captured in the dark room from the scans. For Task II, PAS was defined as the adhesion of the iris to the trabecular meshwork. The diagnostic performance of the 3D DGS was evaluated in both tasks with gonioscopic records as reference. Main Outcome Measures The area under the curve (AUC), sensitivity, and specificity of the 3D DGS were calculated. Results In Task I, 29.4% of patients had a narrow angle. The AUC, sensitivity, and specificity of 3D DGS on the external testing datasets were 0.943 (0.933–0.953), 0.867 (0.838–0.895), and 0.878 (0.859–0.896), respectively. For Task II, 13.8% of patients had PAS. The AUC, sensitivity, and specificity of 3D DGS were 0.902 (0.818–0.985), 0.900 (0.714–1.000), and 0.890 (0.841–0.938), respectively, on the external testing set at quadrant level following normal clinical practice; and 0.885 (0.836–0.933), 0.912 (0.816–1.000), and 0.700 (0.660–0.741), respectively, on the external testing set at clock-hour level. Conclusions The 3D DGS is effective in detecting eyes with suspected PACG. It has the potential to be used widely in the primary eye care community for screening of subjects at high risk of developing PACG.
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- 2022
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3. GlauCUTU: Time Until Perceived Virtual Reality Perimetry With Humphrey Field Analyzer Prediction-Based Artificial Intelligence
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Patthapol Kunumpol, Nichapa Lerthirunvibul, Phongphan Phienphanich, Adirek Munthuli, Kanjapat Temahivong, Visanee Tantisevi, Anita Manassakorn, Sunee Chansangpetch, Rath Itthipanichpong, Kitiya Ratanawongphaibul, Prin Rojanapongpun, and Charturong Tantibundhit
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General Computer Science ,General Engineering ,General Materials Science - Published
- 2022
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4. Treatment Outcomes Using the PAUL Glaucoma Implant to Control Intraocular Pressure in Eyes with Refractory Glaucoma
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Victor Koh, Paul Chew, Giacinto Triolo, Kin Sheng Lim, Keith Barton, Cecilia Aquino, Chelvin Sng, Henrietta Ho, Prin Rojanapongpun, Visanee Tantisevi, Fang Seng Kheong, Clement Tham, and Poemen Chan
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Intraocular pressure ,medicine.medical_specialty ,genetic structures ,business.industry ,medicine.medical_treatment ,010102 general mathematics ,Treatment outcome ,Glaucoma ,General Medicine ,medicine.disease ,01 natural sciences ,eye diseases ,Surgery ,Clinical trial ,03 medical and health sciences ,0302 clinical medicine ,Refractory ,030221 ophthalmology & optometry ,Glaucoma surgery ,medicine ,sense organs ,Implant ,0101 mathematics ,business ,Cohort study - Abstract
Purpose To investigate efficacy 1 year after implantation of a novel glaucoma tube shunt, the PAUL Glaucoma Implant (PGI; Advanced Ophthalmic Innovations, Singapore, Republic of Singapore), in the treatment of eyes with refractory glaucoma. Design Clinical trial. Participants Glaucoma patients who are recalcitrant to maximum tolerated medical therapy and require tube shunt surgery. Methods Interventional cohort study involving consecutive PGIs implanted at 6 international centers between December 1, 2017, and December 1, 2018. All the participants were followed up for 1 year after surgery. Main Outcome Measures The primary outcome measure was failure, defined prospectively as intraocular pressure (IOP) of more than 21 mmHg or less than 20% reduction from the preoperative baseline on 2 consecutive visits, 3 months or more after surgery; persistent late hypotony, defined as IOP of less than 6 mmHg on 2 consecutive visits after 3 months; additional glaucoma surgery; loss of light perception vision; or removal of the implant for any reason. Results Of 82 patients enrolled, 74 (74 eyes) completed 12 months of follow-up. The mean age ± standard deviation at enrollment was 62.3±14.7 years, 73.0% were men, and 36.5% had secondary glaucoma. One year after surgery, 4 patients (5.4%) fulfilled the surgical criteria for failure, 68.9% (51/74 eyes) were deemed complete successes, and 93.2% (69/74 eyes) were considered qualified successes. Compared with the medicated preoperative IOP (23.1±8.2 mmHg), the postoperative IOPs at 6 and 12 months were 13.8±4.0 mmHg and 13.2±3.3 mmHg, respectively (P Conclusions The PGI demonstrated comparable efficacy with other currently available implants, with almost three quarters of the enrolled patients with refractory glaucoma achieving complete surgical success after 1 year of follow-up.
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- 2020
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5. Ciliochoroidal effusion and its association with the outcomes of micropulse transscleral laser therapy in glaucoma patients: a pilot study
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Sunee Chansangpetch, Natnaree Taechajongjintana, Kitiya Ratanawongphaibul, Rath Itthipanichpong, Anita Manassakorn, Visanee Tantisevi, Prin Rojanapongpun, and Shan C. Lin
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Multidisciplinary ,Treatment Outcome ,Humans ,Glaucoma ,Pilot Projects ,Laser Therapy ,Choroidal Effusions ,Intraocular Pressure ,Retrospective Studies - Abstract
We investigate the development of ciliochoroidal effusion following micropulse transscleral laser therapy (MPTLT) and evaluate the relationship between the early postoperative ciliochoroidal effusion (ECE) and short-term treatment outcomes. Glaucoma patients who underwent MPTLT were assessed for ciliochoroidal effusion by anterior segment optical coherence tomography (AS-OCT) at postoperative 1, 4, 12 weeks. The subjects were classified based on AS-OCT findings at postoperative 1 week into eyes with and without ECE. The absolute intraocular pressure (IOP), IOP reduction and number of antiglaucoma medications were compared between eyes with and without ECE. A total of 50 eyes were included, of which 23 (46%) developed ciliochoroidal effusion at postoperative 1 week. Almost all effusion resolved at 4 weeks. At 12 weeks, the mean IOP (SD) significantly decreased from 28.5 (12.8) mmHg to 17.8 (10.5) mmHg (p
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- 2022
6. Digital Gonioscopy Based on Three-dimensional Anterior-Segment OCT: An International Multicenter Study
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Fei, Li, Yifan, Yang, Xu, Sun, Zhen, Qiu, Shihao, Zhang, Tin Aung, Tun, Baskaran, Mani, Monisha Esther, Nongpiur, Sunee, Chansangpetch, Kitiya, Ratanawongphaibul, Anita, Manassakorn, Visanee, Tantisevi, Prin, Rojanapongpun, Fengbin, Lin, Weijing, Cheng, Rouxi, Zhou, Yuhong, Liu, Yu, Chen, Jian, Xiong, Mingkui, Tan, Tin, Aung, Yanwu, Xu, Daniel S W, Ting, and Xiulan, Zhang
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Adult ,Male ,Gonioscopy ,Iris ,Middle Aged ,Sensitivity and Specificity ,Cornea ,Cross-Sectional Studies ,Imaging, Three-Dimensional ,Trabecular Meshwork ,Area Under Curve ,Humans ,Female ,Diagnosis, Computer-Assisted ,Glaucoma, Angle-Closure ,Intraocular Pressure ,Tomography, Optical Coherence ,Aged - Abstract
To develop and evaluate the performance of a 3-dimensional (3D) deep-learning-based automated digital gonioscopy system (DGS) in detecting 2 major characteristics in eyes with suspected primary angle-closure glaucoma (PACG): (1) narrow iridocorneal angles (static gonioscopy, Task I) and (2) peripheral anterior synechiae (PAS) (dynamic gonioscopy, Task II) on OCT scans.International, cross-sectional, multicenter study.A total of 1.112 million images of 8694 volume scans (2294 patients) from 3 centers were included in this study (Task I, training/internal validation/external testing: 4515, 1101, and 2222 volume scans, respectively; Task II, training/internal validation/external testing: 378, 376, and 102 volume scans, respectively).For Task I, a narrow angle was defined as an eye in which the posterior pigmented trabecular meshwork was not visible in more than 180° without indentation in the primary position captured in the dark room from the scans. For Task II, PAS was defined as the adhesion of the iris to the trabecular meshwork. The diagnostic performance of the 3D DGS was evaluated in both tasks with gonioscopic records as reference.The area under the curve (AUC), sensitivity, and specificity of the 3D DGS were calculated.In Task I, 29.4% of patients had a narrow angle. The AUC, sensitivity, and specificity of 3D DGS on the external testing datasets were 0.943 (0.933-0.953), 0.867 (0.838-0.895), and 0.878 (0.859-0.896), respectively. For Task II, 13.8% of patients had PAS. The AUC, sensitivity, and specificity of 3D DGS were 0.902 (0.818-0.985), 0.900 (0.714-1.000), and 0.890 (0.841-0.938), respectively, on the external testing set at quadrant level following normal clinical practice; and 0.885 (0.836-0.933), 0.912 (0.816-1.000), and 0.700 (0.660-0.741), respectively, on the external testing set at clock-hour level.The 3D DGS is effective in detecting eyes with suspected PACG. It has the potential to be used widely in the primary eye care community for screening of subjects at high risk of developing PACG.
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- 2021
7. Medical Therapy in Angle Closure Glaucoma
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Prin Rojanapongpun and Visanee Tantisevi
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Intraocular pressure ,medicine.medical_specialty ,genetic structures ,Hypotensive agents ,Side effect ,Medical treatment ,business.industry ,Glaucoma ,medicine.disease ,eye diseases ,Laser iridotomy ,Ophthalmology ,medicine ,Angle-closure glaucoma ,business ,Medical therapy - Abstract
Medical therapy plays essential roles in the management of angle closure glaucoma (ACG) both in intraocular pressure (IOP) reduction and in modifying angle anatomy. The administration of multiple topical and systemic hypotensive agents usually enable IOP reduction rapidly. Miotics help to prepare the iris for a definitive laser iridotomy or iridoplasty. Anti-inflammatory and analgesic medications must also be employed to reduce associated symptoms. The use of miotics must be cautious as it may worsen angle closure mechanisms like ciliary block and lens-related mechanism. For chronic ACG, medical treatment could be a mainstay if IOP remains persistently high after laser or surgical treatment. All anti-hypertensive agents work with variable effects depending on the stage and mechanism of angle closure. The relevant mode of action, efficacy, and side effect of each different class of hypotensive medications are described in detail. Prostaglandins are the most effective topical hypotensive agent and could reduce IOP in variable degrees of angle closure. New medications and molecules, still novel for ACG, could have potential use in the future.
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- 2020
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8. Intraocular Pressure Fluctuation in Angle Closure Glaucoma
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Anita Manassakorn, Sunee Chansangpetch, and Prin Rojanapongpun
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Intraocular pressure ,medicine.medical_specialty ,genetic structures ,business.industry ,medicine.medical_treatment ,Disease progression ,Glaucoma ,Cataract surgery ,medicine.disease ,eye diseases ,Primary angle closure suspect ,Clinic visit ,Ophthalmology ,Medicine ,Trabeculectomy ,Angle-closure glaucoma ,sense organs ,business - Abstract
Angle closure glaucoma tends to have a higher magnitude and greater fluctuation of intraocular pressure (IOP), and thus leading to more blindness. Primary angle closure glaucoma (PACG) has higher IOP than other subtypes of angle closure and the normal subjects. The presence of PAS usually correlates with high IOP. The characteristic of diurnal IOP varies among the different subtypes of angle closure disease, greatest in PACG and smallest in primary angle closure suspect. However, the diurnal IOP fluctuation does not always characterize well in the different subtypes of angle closure disease. Cataract surgery, glaucoma laser procedure, and trabeculectomy in angle closure eyes potentially offer an advantage in flattening diurnal IOP curve. Some literatures suggest that greater 24-h diurnal IOP is associated with disease progression in this glaucoma entity, however, the available data are still limited and controversial. Nevertheless, diurnal IOP is worth exploring in PACG individuals who show glaucoma progression despite a favorable clinic visit IOP.
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- 2020
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9. Anterior Segment Imaging for Angle Closure
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Sunee Chansangpetch, Shan C. Lin, and Prin Rojanapongpun
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Computer science ,Gonioscopy ,Microscopy, Acoustic ,Closure (topology) ,Ultrasound biomicroscopy ,Glaucoma ,03 medical and health sciences ,0302 clinical medicine ,Optical coherence tomography ,Anterior Eye Segment ,medicine ,Humans ,Prospective Studies ,Reference standards ,Intraocular Pressure ,medicine.diagnostic_test ,Reproducibility of Results ,medicine.disease ,Clinical Practice ,Ophthalmology ,030221 ophthalmology & optometry ,Optometry ,Tomography ,Glaucoma, Angle-Closure ,Tomography, Optical Coherence ,030217 neurology & neurosurgery - Abstract
Purpose To summarize the role of anterior segment imaging (AS-imaging) in angle closure diagnosis and management, and the possible advantages over the current standard of gonioscopy. Design Literature review and perspective. Methods Review of the pertinent publications with interpretation and perspective in relation to the use of AS-imaging in angle closure assessment focusing on anterior segment optical coherence tomography and ultrasound biomicroscopy. Results Several limitations have been encountered with the reference standard of gonioscopy for angle assessment. AS-imaging has been shown to have performance in angle closure detection compared to gonioscopy. Also, imaging has greater reproducibility and serves as better documentation for long-term follow-up than conventional gonioscopy. The qualitative and quantitative information obtained from AS-imaging enables better understanding of the underlying mechanisms of angle closure and provides useful parameters for risk assessment and possible prediction of the response to laser and surgical intervention. The latest technologies—including 3-dimensional imaging—have allowed for the assessment of the angle that simulates the gonioscopic view. These advantages suggest that AS-imaging has a potential to be a reference standard for the diagnosis and monitoring of angle closure disease in the future. Conclusions Although gonioscopy remains the primary method of angle assessment, AS-imaging has an increasing role in angle closure screening and management. The test should be integrated into clinical practice as an adjunctive tool for angle assessment. It is arguable that AS-imaging should be considered first-line screening for patients at risk for angle closure.
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- 2018
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10. Automated Glaucoma Screening from Retinal Fundus Image Using Deep Learning
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A. Yaemsuk, Prin Rojanapongpun, Rath Itthipanichpong, S. Phasuk, Visanee Tantisevi, Anita Manassakorn, Sunee Chansangpetch, Charturong Tantibundhit, P. Poopresert, and Pukkapol Suvannachart
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genetic structures ,Fundus Oculi ,Computer science ,Fundus image ,Glaucoma ,02 engineering and technology ,Diagnostic Techniques, Ophthalmological ,Fundus (eye) ,Glaucoma screening ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,chemistry.chemical_compound ,Deep Learning ,0302 clinical medicine ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Humans ,Retina ,Artificial neural network ,Blindness ,business.industry ,Deep learning ,020207 software engineering ,Pattern recognition ,Retinal ,Image segmentation ,medicine.disease ,eye diseases ,medicine.anatomical_structure ,chemistry ,sense organs ,Artificial intelligence ,business ,Algorithms - Abstract
Glaucoma is the second leading cause of blindness worldwide. This paper proposes an automated glaucoma screening method using retinal fundus images via the ensemble technique to fuse the results of different classification networks and the result of each classification network was fed as an input to a simple artificial neural network (ANN) to obtain the final result. Three public datasets, i.e., ORIGA-650, RIM-ONE R3, and DRISHTI-GS were used for training and evaluating the performance of the proposed network. The experimental results showed that the proposed network outperformed other state-of-art glaucoma screening algorithms with AUC of 0.94. Our proposed algorithms showed promising potential as a medical support system for glaucoma screening especially in low resource countries.
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- 2019
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11. Effect of oral statin use on mitomycin-C augmented trabeculectomy outcomes
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Abhibol Inobhas, Prin Rojanapongpun, Anita Manassakorn, Visanee Tantisevi, and Sunee Chansangpetch
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Male ,Visual acuity ,Eye Diseases ,genetic structures ,Antimetabolites ,Vision ,Physiology ,medicine.medical_treatment ,Visual Acuity ,Administration, Oral ,Social Sciences ,Glaucoma ,Kaplan-Meier Estimate ,Medical Conditions ,Animal Cells ,Medicine and Health Sciences ,Glaucoma surgery ,Psychology ,Trabeculectomy ,Connective Tissue Cells ,Multidisciplinary ,Hazard ratio ,Ophthalmic Procedures ,Drugs ,Middle Aged ,Treatment Outcome ,Connective Tissue ,symbols ,Medicine ,Female ,Sensory Perception ,Fluorouracil ,Anatomy ,Cellular Types ,medicine.symptom ,Research Article ,Adult ,medicine.medical_specialty ,Statin ,medicine.drug_class ,Mitomycin ,Science ,Surgical and Invasive Medical Procedures ,symbols.namesake ,Musculoskeletal System Procedures ,Ocular System ,Internal medicine ,Tissue Repair ,medicine ,Humans ,Poisson regression ,Aged ,Retrospective Studies ,Pharmacology ,Wound Healing ,business.industry ,Statins ,Cognitive Psychology ,Biology and Life Sciences ,Retrospective cohort study ,Cell Biology ,Fibroblasts ,medicine.disease ,eye diseases ,Ophthalmology ,Biological Tissue ,Eyes ,Cognitive Science ,Perception ,sense organs ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,Physiological Processes ,business ,Head ,Follow-Up Studies ,Neuroscience - Abstract
Purpose The effect of statins on wound healing is controversial, and their effect on trabeculectomy outcomes remains unclear. This study aimed to examine the relationship between oral statin use and trabeculectomy outcomes. Methods Medical records of patients who underwent primary mitomycin-C augmented trabeculectomy with 2 years of follow-up were reviewed. Pre- and postoperative intraocular pressures (IOP) and numbers of medications, subconjunctival 5-fluorouracil (5-FU) injections, and bleb-needling procedures were compared between statin users and nonusers. Failure was defined as an eye that failed to achieve a 20% lowering of IOP from baseline or had an IOP > 21 mm Hg, as well as an eye that required further surgical intervention, developed hypotony, or had no light perception visual acuity. Results In total, 158 subjects were enrolled, with 47 eyes from statin users and 111 eyes from statin nonusers. The 24-month cumulative probability of failure was 78.7% for statin users and 60.4% for nonusers (P = .013). Cox proportional-hazards modeling showed a significantly higher hazard risk in statin users (adjusted hazard ratio 1.61, P = .026). There were no significant between-group differences in mean IOPs or number of medications (both P > .05) at 24 months. Multivariable Poisson regression analysis that statin use was associated with increased numbers of 5-FU injections (P = .014) and bleb-needling procedures (P = .031). Conclusions This study demonstrated that oral statin use was associated with higher rates of trabeculectomy failure and increased numbers of 5-FU injections and bleb-needling procedures.
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- 2021
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12. Factors related to hypertensive phase after glaucoma drainage device implantation
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Prin Rojanapongpun, Visanee Tantisevi, Orathai Pitukcheewanont, and Sunee Chansangpetch
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Intraocular pressure ,medicine.medical_specialty ,Visual acuity ,Heart disease ,Glaucoma ,glaucoma implant ,surgical outcomes ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,Internal medicine ,medicine ,risk factors ,Risk factor ,Survival analysis ,Original Research ,Aspirin ,business.industry ,Clinical Ophthalmology ,post-operative intraocular pressure ,medicine.disease ,030221 ophthalmology & optometry ,medicine.symptom ,Complication ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Orathai Pitukcheewanont,1 Visanee Tantisevi,1 Sunee Chansangpetch,2 Prin Rojanapongpun1 1Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; 2Department of Ophthalmology, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand Background: The aim of the study was to evaluate factors related to hypertensive phase (HP) after glaucoma drainage device (GDD) implantation.Patients and methods: Retrospective charts review of glaucoma patients who underwent GDD implantation and completed 12 months of follow-up at King Chulalongkorn Memorial Hospital since 2004 was performed. Patients were divided into two groups according to the presence or absence of HP. The data were analyzed for factors associated with HP. The surgical outcomes including surgical failure, post-operative visual acuity (VA), post-operative number of medications, post-operative intraocular pressure (IOP), and post-operative complication were compared between the two groups.Results: Seventy-two patients were included. Most were diagnosed with secondary glaucoma (N=51, 70.8%), and Baerveldt was the most implanted GDD (N=49, 68.1%). Mean ± SD of IOP was significantly lower: 27.1±9.6 mmHg at pre-operation and 13.7±59 mmHg at 12-month follow-up (p
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- 2018
13. Selective Laser Trabeculoplasty for Primary Angle Closure With Persistently Elevated Intraocular Pressure After Iridotomy
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Prin Rojanapongpun, Michael Belkin, Jimmy S. M. Lai, Ching Lin Ho, Ma Cecilia Aquino, Hon Tym Wong, Mario V. Aquino, Yaniv Barkana, and Yariv Gerber
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Male ,Reoperation ,Iridectomy ,Intraocular pressure ,medicine.medical_specialty ,genetic structures ,Selective laser trabeculoplasty ,medicine.medical_treatment ,Gonioscopy ,Iris ,Glaucoma ,Trabeculectomy ,Elevated intraocular pressure ,Trabecular Meshwork ,Ophthalmology ,medicine ,Humans ,Angle-closure glaucoma ,Intraocular Pressure ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Follow up studies ,Middle Aged ,medicine.disease ,eye diseases ,Chronic Disease ,Female ,Ocular Hypertension ,Laser Therapy ,sense organs ,Glaucoma, Angle-Closure ,business ,Follow-Up Studies - Abstract
To determine whether selective laser trabeculoplasty (SLT) can lower intraocular pressure (IOP) in eyes with chronic primary angle closure, elevated IOP, and a patent iridotomy.Patients with chronic angle closure who had underwent iridotomy, had an IOP greater than 21 mm Hg and a gonioscopically visible pigmented trabecular meshwork for at least 90 degrees were enrolled. SLT was applied to open angle segments. Duration of follow-up was 6 months.Sixty eyes of 60 patients were enrolled. The mean baseline IOP was 24.6+/-2.5 mm Hg. At 6 months, IOP reduction ofor =3 mm Hg or 4 mm Hg was measured in 82% and 72% of eyes, respectively, and IOP reduction ofor =20% or 30% was measured in 54% and 24% of eyes, respectively. When only eyes that were treated with the same number or fewer medications were considered, these IOP reductions were measured in 67%, 58%, 43%, and 15%, respectively. During the study period 1 eye (1.7%) required trabeculectomy owing to IOP elevation shortly after the SLT. There were no other significant complications attributable to SLT.SLT seems to be a safe and effective method of reducing IOP in many eyes with primary angle closure and a patent iridotomy in which there is a sufficient extent of visible trabecular meshwork.
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- 2009
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14. Clinical Primary Angle-closure Glaucoma: Fundamental Concepts of Chronic Angle-closure Glaucoma
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Prin Rojanapongpun, George L Spaeth, Kuldev Singh, and Tanuj Dada
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Ophthalmology ,medicine.medical_specialty ,business.industry ,Chronic angle-closure glaucoma ,Medicine ,business ,Primary angle-closure glaucoma - Published
- 2007
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15. A 6-week, double-masked, paralle-group study of the efficacy and safety of travoprost 0.004% compared with latanoprost 0:005%/timolol 0.5% in patients with primary open-angle glaucoma or ocular hypertension
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Ian A. Cunliffe, Jean P. Renard, Prin Rojanapongpun, and Wendy A. Franks
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Male ,Intraocular pressure ,genetic structures ,Eye disease ,Glaucoma ,Ocular hypertension ,Timolol ,Placebo ,Tonometry, Ocular ,chemistry.chemical_compound ,Travoprost ,Double-Blind Method ,Humans ,Medicine ,Pharmacology (medical) ,Latanoprost ,Antihypertensive Agents ,Intraocular Pressure ,Aged ,Pharmacology ,business.industry ,Cloprostenol ,medicine.disease ,eye diseases ,Drug Combinations ,Treatment Outcome ,chemistry ,Anesthesia ,Prostaglandins F, Synthetic ,Female ,Ocular Hypertension ,sense organs ,Ophthalmic Solutions ,business ,Glaucoma, Open-Angle ,medicine.drug - Abstract
Objective: The objective of this study was to directly compare the intraocular pressure (IOP)-lowering efficacy and safety of travoprost 0.004% eyedrops with the fixed combination of latanoprost 0.005%/timolo10.5% eyedrops in patients with primary open-angle glaucoma or ocular hypertension. Methods: This was a randomized, double-masked, multicenter, parallel-group, active-controlled study. Adult subjects with open-angle glaucoma (with or without pseudoexfoliation or pigment dispersion component) or ocular hypertension were eligible to participate if their IOP was inadequately controlled with ≥4 weeks of β-blocker monotherapy, as indicated by IOP of 22 to 36 mm Hg at 9 AM at screening. Patients were randomly assigned in a 1:1 ratio to receive placebo + travoprost or latanoprost/timolol + placebo. Patients in the travoprost group administered travoprost at 9 PM and placebo at 9 AM ; patients in the latanoprosttimolol group administered latanoprost/timolol at 9 AM and placebo at 9 PM . IOP measurements were performed using Goldmann applanation tonometry at 9 AM and 5 PM at the week-2 and week-6 visits. Both volunteered and elicited reports of adverse events were collected; all patients who were randomized and received ≥1 dose of study drug were included in the safety analysis. Results: One hundred ten patients were randomized, of whom 106 patients were evaluable (travoprost, n = 50; latanoprost/timolol, n = 56). There were no statistically significant differences at baseline between the treatment groups, based on age group, sex, race, iris color, or diagnosis. Mean IOP values were not statistically different between groups at baseline or during treatment. In the pooled results for 9 Am assessment at weeks 2 and 6, mean (SEM) IOP reductions for travoprost and latanoprost/imolol were 7.0 (0.5) and 6.4 (0.5) mm Hg, respectively (P = NS). Adverse events related to therapy were mild in nature, and there were no statistically significant differences between the 2 treatment groups. The most frequently experienced adverse events in the travoprost group were ocular hyperemia (9.3%), foreign body sensation (5.6%), abnormal vision (1.9%), allergic reaction (1.9%), conjunctivitis (1.9%), dacryocystitis (1.9%), eye discharge (1.9%), eye pruritus (1.9%), lid edema (1.9%), lid erythema (1.9%), and tearing (1.9%). In the latanoprost/timolol group, the most frequently experienced adverse events were cataract (1.8%), dry eyes (1.8%), eye pruritus (1.8%), foreign body sensation (1.8%), and ocular hyperemia (1.8%). Conclusions: Mean IOP changes from baseline fortravoprost 0.004% and latanoprost 0.005%/timolol 0.5% fixed combination were not significantly different at follow-up in these patients. Both medications were well tolerated.
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- 2006
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16. List of Contributors
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Leslie Abrams-Tobe, Samer A Abuswider, Jorge Acosta, Pavi Agrawal, Oscar Albis-Donado, Luciana M Alencar, R Rand Allingham, Annahita Amireskandari, Nitin Anand, Florent Aptel, Makoto Araie, Enyr S Arcieri, Ehud I Assia, Tin Aung, George Baerveldt, Nafees Baig, Annie K Baik, Rajendra K Bansal, Mirko Babic, Anita Barikian, Howard Barnebey, Keith Barton, Christophe Baudouin, Allen Beck, Sonya L Bennett, Stanley J Berke, Tui H Bevin, Shibal Bhartiya, Philip A Bloom, Dana M Blumberg, Kathryn Bollinger, Christopher Bowd, John W Boyle, James D Brandt, David C Broadway, Stephen Brocchini, Alain M Bron, Donald L Budenz, Catey Bunce, Claude F Burgoyne, Jennifer Burr, Yvonne M Buys, Louis B Cantor, Joseph Caprioli, Roberto G Carassa, Daniel S Casper, Yara Paula Catoira-Boyle, Piero Ceruti, Debasis Chakrabarti, Raka Chakrabarti, Pratap Challa, Errol Chan, Peter T Chang, Robert T Chang, Balwantray C Chauhan, Aiyin Chen, Jason Cheng, Paul TK Chew, Mark Chiang, Etsuo Chihara, Neil T Choplin, George A Cioffi, Colin I Clement, Anne L Coleman, Nathan G Congdon, Michael A Coote, Vital P Costa, David P Crabb, Alan S Crandall, E Randy Craven, Laura Crawley, Jonathan G Crowston, Emmett T Cunningham, Elie Dahan, Annegret H Dahlmann-Noor, Karim F Damji, Alexander Day, Me'Ja Day, Philippe Denis, Syril Dorairaj, J Crawford Downs, Gordon N Dutton, Hassan Eldaly, Fathi F El Sayyad, Benedetto Falsini, Francisco Fantes, Herbert P Fechter, Robert D Fechtner, Ronald L Fellman, Eva Fenwick, Arosha Fernando, Ann Caroline Fisher, Frederick W Fitzke, Brad Fortune, Paul Foster, Panayiota Founti, Jeffrey Freedman, Stefano A Gandolfi, Julián García-Feijoó, David Garway-Heath, Gus Gazzard, Steven J Gedde, Noa Geffen, Stelios Georgoulas, Annette Giangiacomo, Katie Gill, Zisis Gkatzioufas, Ivan Goldberg, Pieter Gouws, Stuart L Graham, Alana L Grajewski, David S Greenfield, Franz Grehn, Daniel E Grigera, Ronald L Gross, Davinder S Grover, Rafael Grytz, Meenakashi Gupta, Neeru Gupta, Carlos Gustavo de Moraes, Ali S Hafez, Farhad Hafezi, Teruhiko Hamanaka, Alon Harris, Marcelo Hatanaka, Matthew J Hawker, Paul R Healey, The late Catherine J Heatley, Dale K Heuer, Eve J Higginbotham, Cornelia Hirn, Roger A Hitchings, Gábor Holló, Ann M Hoste, Andrew Huck, Cindy ML Hutnik, Camille Hylton, Sabita M Ittoop, Farrah Ja'afar, Henry Jampel, Thomas V Johnson, Jost B Jonas, Malik Y Kahook, Michael A Kass, Andreas Katsanos, L Jay Katz, Jill E Keeffe, Thomas Kersey, Naira Khachatryan, Sir Peng Tee Khaw, Albert S Khouri, Dan Kiage, Lee Kiang, Danny Kim, Yoshiaki Kiuchi, Thomas Klink, Helen Koenigsman, Anastasios GP Konstas, Aachal Kotecha, Avinash Kulkarni, Alexander V Kuroyedov, Antoine Labbé, Alan Lacey, Dennis SC Lam, Ecosse L Lamourex, Graham Lee, Paul Lee, Hans G Lemij, Anthony Leoncavallo, Mark R Lesk, Christopher KS Leung, Dexter YL Leung, Leonard A Levin, Richard A Lewis, K Sheng Lim, Ridia Lim, Ricardo de Lima, Yutao Liu, Alastair Lockwood, Sancy Low, Fumihiko Mabuchi, David A Mackey, Rizwan Malik, Anil K Mandal, Steven L Mansberger, Kaweh Mansouri, Giorgio Marchini, Manjula Marella, Keith R Martin, Robert H McGlynn, Steven H McKinley, Stuart J McKinnon, J Ryan McManus, Felipe A Medeiros, André Mermoud, Clive S Migdal, Don Minckler, Anthony CB Molteno, Paolo Mora, Javier Moreno-Montañés, James E Morgan, Sameh Mosaed, Marilita M Moschos, Kelly W Muir, Gonzalo Muñoz, Francisco J Muñoz-Negrete, Arvind Neelakantan, Anil K Negi, Peter A Netland, Paula Anne Newman-Casey, Marcelo T Nicolela, Nuwan Niyadurupola, Magdy A Nofal, Winnie Nolan, Monisha E Nongpiur, Baha'a N Noureddin, Gary D Novack, Brenda Nuyen, Krishnamurthy Palaniswamy, Camille Palma, Ki Ho Park, Richard K Parrish, Maria Papadopoulos, Rajul S Parikh, Louis R Pasquale, Alice Pébay, Sergey Petrov, Jody Piltz-Seymour, Luís Abegão Pinto, Ian F Pitha, Norbert Pfeiffer, Luciano Quaranta, Pradeep Y Ramulu, Emilie Ravinet, Tony Realini, Gema Rebolleda, Nic J Reus, Adam C Reynolds, Douglas J Rhee, Isabelle Riss, Robert Ritch, Charles E Riva, Gloria Roberti, Cynthia J Roberts, Alan L Robin, Prin Rojanapongpun, Sylvain Roy, John F Salmon, Juan Roberto Sampaolesi, Chiara Sangermani, Usman A Sarodia, Jamie Lea Schaefer, Ursula Schloetzer-Schrehardt, Gregory S Schultz, Joel S Schuman, Leonard K Seibold, Tarek M Shaarawy, Peter Shah, Mark B Sherwood, Lineu Oto Shiroma, Brent Siesky, Sergio Estrela Silva, Annapurna Singh, Arun D Singh, Kuldev Singh, Chelvin CA Sng, Brian J Song, George L Spaeth, Alexander Spratt, Ingeborg Stalmans, Robert L Stamper, Kazuhisa Sugiyama, Remo Susanna, Orathai Suwanpimolkul, William H Swanson, Ernst R Tamm, Tak Yee Tania Tai, Angelo P Tanna, Chaiwat Teekhasaenee, Clement CY Tham, Hagen Thieme, Ravi Thomas, Andrew M Thompson, Ravilla D Thulasiraj, John Thygesen, Karim Tomey, Yokrat Ton, Fotis Topouzis, Carol B Toris, Roberto Tosi, James C Tsai, Sonal S Tuli, Anja Tuulonen, Nicola Ungaro, Luke Vale, Leonieke ME van Koolwijk, Reena S Vaswani, Rengaraj Venkatesh, Cristina Venturini, Stephen A Vernon, Eranga N Vithana, Lingam Vijaya, Ananth C Viswanathan, Gabriele Vizzari, Irini C Voudouragkaki, Michael Waisbourd, Mark J Walland, Robert N Weinreb, Mark Werner, Anthony Wells, Boateng Wiafe, Jacob Wilensky, Tina T Wong, Darrell WuDunn, Jennifer LY Yip, Yeni Yucel, Linda M Zangwill, Virginia E Zanutigh, Joseph R Zelefsky, and Thierry Zeyen
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- 2015
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17. Acute Intraocular Pressure Rise
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Prin Rojanapongpun and Orathai Suwanpimolkul
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medicine.medical_specialty ,business.industry ,Ophthalmology ,Medicine ,business ,Intraocular Pressure Rise - Published
- 2015
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18. Tight orbit syndrome: a previously unrecognized cause of open-angle glaucoma
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Prin Rojanapongpun, Jeffrey M. Liebmann, Steve Y.-W. Liang, Matthew Bastian-Jordan, Graham A Lee, Robert Ritch, Kate Lehmann, and Philip Dubois
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Adult ,Male ,medicine.medical_specialty ,Intraocular pressure ,genetic structures ,Open angle glaucoma ,Adolescent ,Vision Disorders ,Glaucoma ,Trabeculectomy ,Young Adult ,Ophthalmology ,medicine ,Orbital Diseases ,Humans ,Treatment Failure ,Glaucoma Drainage Implants ,Intraocular Pressure ,Retrospective Studies ,business.industry ,General Medicine ,Syndrome ,Middle Aged ,medicine.disease ,Decompression, Surgical ,eye diseases ,Optometry ,Female ,sense organs ,Orbit (control theory) ,Visual Fields ,business ,Glaucoma, Open-Angle ,Follow-Up Studies - Abstract
To describe a new syndrome of tight orbit and intractable glaucoma with a poor visual prognosis.A retrospective observational case series of six patients seen at two centres between 2001 and 2007 assessing intraocular pressure (IOP), best-corrected visual acuity and visual field.Three men and three women, ranging in age at diagnosis from 14 to 53 years, demonstrated similar orbital features and progressive visual field loss despite intensive management with medication and laser and operative surgery. Highest IOPs ranged from 30 to 50 mmHg. Trabeculectomy and/or glaucoma drainage devices were attempted in five patients but all failed. One patient underwent orbital decompression with achievement of IOP control. Final IOP at last follow-up was variable; only two patients achieved IOP in the normal range, with the rest ranging from 25 to 40 mmHg. All patients had advanced visual field loss.Tight orbit syndrome presents a serious clinical challenge. Despite maximum medical therapy and surgical intervention IOP is difficult to control, resulting in progressive visual field loss.
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- 2010
19. Plateau iris in Asian subjects with primary angle closure glaucoma
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Lakshmana S. MohanRam, Orathai Chansanti, Desmond Quek, Visanee Tantisevi, Victor Koh, Prin Rojanapongpun, Rajesh S. Kumar, Kelvin Y. C. Lee, Tin Aung, Melissa H. Y. Wong, and Kobkuea Laohapojanart
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Adult ,Male ,Intraocular pressure ,medicine.medical_specialty ,Iridectomy ,genetic structures ,medicine.medical_treatment ,Ultrasound biomicroscopy ,Gonioscopy ,Microscopy, Acoustic ,Glaucoma ,Iris ,Tonometry, Ocular ,Ciliary body ,Asian People ,Trabecular Meshwork ,Plateau iris ,Ophthalmology ,Prevalence ,Medicine ,Humans ,Eye Abnormalities ,Prospective Studies ,Iris (anatomy) ,Intraocular Pressure ,Aged ,Aged, 80 and over ,Singapore ,medicine.diagnostic_test ,business.industry ,Ciliary Body ,Middle Aged ,medicine.disease ,Thailand ,eye diseases ,medicine.anatomical_structure ,Cross-Sectional Studies ,Female ,sense organs ,Laser Therapy ,medicine.symptom ,business ,Glaucoma, Angle-Closure - Abstract
Objective To determine the prevalence of plateau iris in Asian eyes with primary angle closure glaucoma (PACG) using ultrasound biomicroscopy (UBM). Methods In this cross-sectional observational study, subjects older than 40 years with PACG who had a patent laser peripheral iridotomy underwent UBM in 1 eye. Ultrasound biomicroscopy images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least 2 quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. Results One hundred eleven subjects (70 from Singapore, 41 from Thailand) with PACG were recruited. The mean (SD) age was 65.6 (8.1) years, and 63.9% were female. Based on standardized UBM criteria, plateau iris was found in 36 of 111 eyes (32.4%; 95% confidence interval, 24.4%-41.6%). In these 36 eyes, quadrant-wise analysis showed 66.7% had plateau iris in 2 quadrants; 22.2%, in 3 quadrants; and 11.1%, in all quadrants. Conclusions About 30% of PACG eyes with a patent laser peripheral iridotomy were found to have plateau iris on UBM, highlighting the importance of non–pupil block mechanisms in Asian individuals.
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- 2009
20. Contributors
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Abdul Mateen Ahmed, Allen D. Beck, A. Robert Bellows, Tui H. Bevin, Steven V.L. Brown, Teresa C. Chen, John Mark S. de Leon, Lili Farrokh-Siar, Herbert P. Fechter, Madhu S.R. Gorla, James W. Hung, Leslie S. Jones, Pooja Khator, Theodore Krupin, Dennis S.C. Lam, Mark A. Latina, Hester H. Lee, Paul P. Lee, Edgar U. Leuenberger, Shan C. Lin, Tania S. Marcic, Anthony C.B. Molteno, Richard K. Parrish, Robert Ritch, Alan L. Robin, Prin RojanaPongpun, Stanley S. Schocket, Rajesh K. Shetty, M. Bruce Shields, George L. Spaeth, Robert L. Stamper, Clement C.Y. Tham, Molly M. Walsh, David S. Walton, and Jacob T. Wilensky
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- 2008
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21. Configuration of the drainage angle, intraocular pressure, and optic disc cupping in subjects with chronic angle-closure glaucoma
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Paul T K Chew, Prin Rojanapongpun, Tin Aung, Yiong-Huak Chan, and Marcus C C Lim
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Adult ,Male ,medicine.medical_specialty ,Intraocular pressure ,genetic structures ,Anterior Chamber ,Eye disease ,Optic Disk ,Gonioscopy ,Glaucoma ,Timolol ,Aqueous Humor ,chemistry.chemical_compound ,Trabecular Meshwork ,Ophthalmology ,Optic Nerve Diseases ,medicine ,Humans ,Prospective Studies ,Latanoprost ,Antihypertensive Agents ,Intraocular Pressure ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Middle Aged ,medicine.disease ,eye diseases ,Surgery ,medicine.anatomical_structure ,chemistry ,Chronic Disease ,Prostaglandins F, Synthetic ,Female ,sense organs ,Trabecular meshwork ,business ,Glaucoma, Angle-Closure ,Optic disc ,medicine.drug - Abstract
To investigate the relationship between drainage angle configuration with untreated intraocular pressure (IOP) and optic disc cupping in subjects with chronic angle-closure glaucoma (CACG).Prospective, observational study.Two hundred seventy-five Asian subjects with CACG who participated in a randomized controlled trial that investigated the IOP-reducing effect of latanoprost and timolol.Chronic angle-closure glaucoma was defined as the presence of glaucomatous optic neuropathy (with or without a visual field defect), an anterior chamber angle in which the pigmented trabecular meshwork was not visible for at least 180 degrees on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in association with elevated IOP of 21 mmHg or more. Static and dynamic gonioscopy were performed, the angles were graded in each quadrant according to the Shaffer scheme, and the number of clock hours of PAS was recorded. The untreated IOP and vertical cup-to-disc ratio were correlated with mean angle width and extent of PAS.Mean angle width, clock hours of PAS, IOP, and vertical cup-to-disc ratio.Most subjects were female (75%), and the mean age was 62.9+/-9.4 years. The mean angle width was 0.77+/-0.53 and the mean number of clock hours of PAS was 4.77+/-3.2 hours. Untreated IOP correlated with angle width (r = -0.23; P0.001) and clock hours of PAS (r = 0.22; P0.001). Vertical cup-to-disc ratio also correlated with angle width (r = -0.17; P = 0.004) and PAS (r = 0.28; P0.001). Performing a multiple linear regression using baseline IOP as the outcome variable with age, gender, clock hours of PAS, and angle width as predictors, there was a 0.39-mmHg (95% confidence interval, 0.15-0.63) increase in baseline untreated IOP for each unit increase in clock hours of PAS (P = 0.002).In subjects with CACG, the extent of PAS and a narrower width of the drainage angle were associated with higher untreated IOP and a larger vertical cup-to-disc ratio.
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- 2004
22. Intraocular pressure-reducing effects and safety of latanoprost versus timolol in patients with chronic angle-closure glaucoma
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Prin Rojanapongpun, M.V Aquino, Paul T K Chew, and Tin Aung
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Adult ,Male ,Intraocular pressure ,genetic structures ,Glaucoma ,Timolol ,Placebo ,Drug Administration Schedule ,chemistry.chemical_compound ,Double-Blind Method ,medicine ,Humans ,Latanoprost ,Antihypertensive Agents ,Intraocular Pressure ,Aged ,Aged, 80 and over ,Intention-to-treat analysis ,business.industry ,Repeated measures design ,Middle Aged ,medicine.disease ,eye diseases ,Confidence interval ,Ophthalmology ,chemistry ,Anesthesia ,Chronic Disease ,Prostaglandins F, Synthetic ,Female ,sense organs ,business ,Glaucoma, Angle-Closure ,medicine.drug - Abstract
To demonstrate that the intraocular pressure (IOP)-reducing effect of latanoprost once daily is at least as good as that of timolol twice daily in patients with chronic angle-closure glaucoma (CACG).Randomized, double-masked, multicenter 12-week study.In all, 137 patients with unilateral or bilateral CACG were treated with latanoprost, and 138 were treated with timolol.Patients received either latanoprost (9 pm) and a placebo (9 am) or timolol (both 9 am and 9 pm). Intraocular pressure was measured at 9 am and 5 pm at baseline and weeks 2, 6, and 12.The difference between groups in daily IOP (average of 9 am and 5 pm measures) reduction was the primary outcome. Secondary outcomes included differences between groups in IOP reductions at 9 am and 5 pm, and in proportions of patients reaching specified daily IOP levels.Using repeated measures (analysis of covariance: intent to treat), mean changes from baseline in daily IOP levels during 12 weeks were -8.2 mmHg and -5.2 mmHg for latanoprost- and timolol-treated patients, respectively (difference: -3.0 mmHg [95% confidence interval: -4.0, -2.1], P0.001). Greater reductions in IOP levels at both 9 am and 5 pm were found in latanoprost-treated patients (P0.001 for both), and greater proportions of patients receiving latanoprost reached prespecified target daily IOP levels (P0.001 for all 3 target levels tested). Both drugs were well tolerated.Latanoprost administered once daily provides significantly greater IOP reduction in CACG patients than does timolol instilled twice daily.
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- 2002
23. The effects of nicotine on the blood flow of the ophthalmic artery and the finger circulation
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Prin Rojanapongpun and Stephen M. Drance
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Intraocular pressure ,Nicotine ,Glaucoma ,Hemodynamics ,Pilot Projects ,Chewing Gum ,Fingers ,Cellular and Molecular Neuroscience ,Ophthalmic Artery ,Polymethacrylic Acids ,medicine ,Humans ,Intraocular Pressure ,Aged ,Ultrasonography ,Analysis of Variance ,business.industry ,Blood flow ,Middle Aged ,medicine.disease ,Sensory Systems ,Tobacco Use Cessation Devices ,Transcranial Doppler ,Ophthalmology ,Blood pressure ,medicine.anatomical_structure ,Anesthesia ,Polyvinyls ,business ,Blood Flow Velocity ,Glaucoma, Open-Angle ,medicine.drug ,Artery - Abstract
Cigarette smoking is associated with glaucoma. Nicotine from cigarette smoking is known to produce hemodynamic changes. We studied the effect of nicotine on the ophthalmic artery flow velocity using transcranial Doppler ultrasound to measure noninvasively the Peak (systolic) flow velocity (VP), mean-envelope flow velocity (VM) and end-diastolic flow velocity, as well as using a laser Doppler flowmeter on the finger blood flow of the finger prior to and after administration of 2-4 mg nicotine in a gum base. In a pilot project a group of 18 glaucoma patients and 8 normal subjects were tested with nicotine, and another group of 11 glaucoma patients were tested with placebo. VP, VM, and systolic blood pressure were significantly increased while finger blood flow was significantly decreased when comparing the nicotine-tested glaucoma group with the placebo-tested group (P = 0.02074, 0.01479, 0.02185, and 0.04209, respectively). The nicotine-tested group of normals also showed significant changes in VM, systolic blood pressure, and finger blood flow compared to a placebo group. The responses to the small doses of nicotine used in this study (approximately one-third that of cigarette smoking) were not significantly different between the glaucoma and the normal groups.
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- 1993
24. Velocity of ophthalmic arterial flow recorded by Doppler ultrasound in normal subjects
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Prin Rojanapongpun and Stephen M. Drance
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Male ,medicine.medical_specialty ,Retinal Artery ,Systole ,Diastole ,Hemodynamics ,Heart Rate ,Reference Values ,medicine.artery ,Heart rate ,medicine ,Humans ,Ultrasonography ,Sex Characteristics ,business.industry ,Age Factors ,Middle Aged ,Transcranial Doppler ,Surgery ,Ophthalmology ,Flow velocity ,Flow (mathematics) ,Regional Blood Flow ,Ophthalmic artery ,Regression Analysis ,Female ,Nuclear medicine ,business ,Blood Flow Velocity - Abstract
Transcranial Doppler ultrasound (2 MHz) was used to measure ophthalmic arterial blood flow velocity in 60 normal subjects whose mean age (+/- standard deviation) was 54.9 +/- 17.3 years (30 women, mean age, 56.3 +/- 17.5 years and 30 men, mean age, 53.5 +/- 17.3 years). Three or more measurements were recorded from each eye at reference depths of 40 to 45 mm. The peak systolic flow velocity was 45.1 +/- 7.8 cm/sec, mean-enveloped flow velocity was 22.6 +/- 5.1 cm/sec, end diastolic flow velocity was 12.0 +/- 3.4 cm/sec, pulsatility index was 1.5 +/- 0.4, and resistivity index was 0.7 +/- 0.1. No significant differences of flow variables were found between genders. Statistically significant age-related losses of mean-enveloped flow velocity and end diastolic flow velocity were shown (P = .003 and .038). There were no significant differences of flow velocities between right and left eyes when comparing means. Differences greater than 20% between eyes were found in ten subjects (16.7%) for peak systolic flow velocity, in 18 subjects (30.4%) for mean-enveloped flow velocity, and in 21 subjects (34.8%) for end diastolic flow velocity, but resistivity indexes were comparable in all cases. Ten subjects had flow velocities measured at two different depths separated by 10 mm (40 to 45 mm vs 50 to 55 mm) in the same orbit and showed that peak systolic flow velocity and mean-enveloped flow velocity were significantly higher (P = .006 and .021) at the greater depth. Recognizable differences in shape of the spectrograms obtained from the younger subjects (or = 30 years) and the older subjects (or = 70 years) were found.
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- 1993
25. Clear Corneal Graft Overlying the Seton Tube to Facilitate Laser Suture Lysis
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Robert Ritch and Prin Rojanapongpun
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medicine.medical_specialty ,Lysis ,Corneal graft ,Ocular Hypotension ,Aqueous humor ,law.invention ,Corneal Transplantation ,law ,Humans ,Medicine ,Silicone tube ,Fibrous joint ,Sutures ,business.industry ,Suture Techniques ,Glaucoma ,Laser ,Surgery ,Nylons ,Ophthalmology ,medicine.anatomical_structure ,Drainage ,Laser Therapy ,Implant ,Molteno Implants ,business - Abstract
Purpose To reduce hypotony and shallowing of the anterior chamber after seton implantation. Methods The silicone tube is ligated with an 8-0 nylon suture and a clear corneal graft placed over the tube to facilitate postoperative laser suture lysis. Results Laser suture lysis has been performed in 34 cases to date with a follow-up period of up to 26 months. No severe complications occurred after laser suture lysis. Conclusions This technique provides another option to increase drainage postoperatively without the risk of releasable sutures or instrumentation within the eye.
- Published
- 1996
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