81 results on '"Chan HHL"'
Search Results
2. CONTINUING FINGOLIMOD AFTER DEVELOPMENT OF MACULAR EDEMA: A CASE REPORT
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Li, V, Kane, J, Chan, HHL, Hall, AJ, Butzkueven, H, Li, V, Kane, J, Chan, HHL, Hall, AJ, and Butzkueven, H
- Published
- 2014
3. Use of Q-switched ruby laser in the treatment of nevus of Ota indifferent age groups
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Kono, T, Chan, HHL, Ercocen, AR, Kikuchi, Y, Uezono, S, Iwasaka, S, Isago, T, Nozaki, M, and Tokyo Womens Med Univ, Dept Plast & Reconstruct Surg, Shinjuku Ku, Tokyo 1628666, Japan -- Tokyo Womens Med Univ, Dept Anesthesiol, Tokyo, Japan -- Cumhuriyet Univ Fac Med, Dept Plast & Reconstruct Surg, Sivas, Turkey -- Univ Hong Kong, Div Dermatol, Hong Kong, Hong Kong, Peoples R China
- Subjects
different age groups ,Q-switched ruby laser ,nevus of Ota - Abstract
WOS: 000183764900010, PubMed ID: 12766962, Background and Objectives: Nevus of Ota is a form of dermal melanocytic hamartoma that appears as a bluish discoloration in the trigeminal region. Although Q-switched lasers provide effective treatment, the appropriate age at which to start that treatment is not known. Our aim is to compare the clinical efficacy and safety of Q-switched ruby laser (QSRL) in the treatment of nevus of Ota in different age groups. Study Design/Materials and Methods: Our study included 46 children and 107 adults with nevus of Ota, which had been treated with QSRL that achieved excellent (75% or more) to complete response. The laser parameters were 694-nm wavelength, 30 nanoseconds pulse duration, 4-mm spot size, and 5-7 J/cm(2) fluence at 3-4 month intervals. We assessed the mean number of treatment sessions and the degree of complications in the two age groups of patients. Results: The mean number of treatment sessions to achieve significance to complete clearing was 3.5 for the younger age group and 5.9 for the older age group (P=0.0001). The complication rate for the younger age group was 4.8% as compared to 22.4% for the older age group. Conclusions: The use of QSRL for the treatment of nevus of Ota in children can achieve an excellent result in fewer sessions and at a lower complication rate than later treatment. The risk of recurrence is a concern, however, and further long-term study is necessary to address this issue.
- Published
- 2003
4. Treatment of divided nevus of the penis
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Kono, T, Ercocen, AR, Nozaki, M, Kikuchi, Y, Chan, HHL, and Tokyo Womens Med Univ, Dept Plast & Reconstruct Surg, Tokyo, Japan -- Cumhuriyet Univ, Fac Med, Dept Plast & Reconstruct Surg, Sivas, Turkey -- Univ Hong Kong, Div Dermatol, Hong Kong, Hong Kong, Peoples R China
- Abstract
WOS: 000174726500243, …
- Published
- 2002
5. Patient with Leriche's syndrome and concomitant superior mesenteric aneurysm: Evaluation with contrast-enhanced three-dimensional magnetic resonance angiography, computed tomography angiography and digital subtraction angiography
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Chan, HHL, primary, Tai, KS, additional, and Yip, LKC, additional
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- 2005
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6. Outpatient, short-term, once-daily, diluted, 0.1% mometasone furoate wet-wraps for childhood atopic eczema
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Tang, Wym, primary, Chan, Hhl, additional, Lam, Vmf, additional, Chong, Ly, additional, and Lo, Kk, additional
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- 1999
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7. The reliability of upper limb anthropometry in older Chinese people
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Kwok, T, primary, Woo, J, additional, Chan, HHL, additional, and Lau, E, additional
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- 1997
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8. The Asian dermatologic patient: review of common pigmentary disorders and cutaneous diseases.
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Ho SGY and Chan HHL
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- 2009
9. Blending community service and teaching to open vision care and eye health awareness to university students
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Do, Cw, Lily Chan, Wong, Hhw, Chu, G., Yu, Wy, Pang, Pck, Cheong, Am, Ting, Pwk, Lam, Tc, Kee, Cs, Lam, A., and Chan, Hhl
10. Development of a Preclinical Double Model of Mandibular Irradiated Bone and Osteoradionecrosis in New Zealand Rabbits.
- Author
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Ruaro A, Taboni S, Chan HHL, Mondello T, Lindsay P, Komal T, Alessandrini L, Sbaraglia M, Bellan E, Maroldi R, Townson J, Daly MJ, Re F, Pasini C, Krengli M, Sartore L, Russo D, Nicolai P, Ferrari M, Gilbert RW, and Irish JC
- Abstract
Purpose: Radiotherapy (RT) plays a crucial role in head and neck (HN) cancer treatment. Nevertheless, it can lead to serious and challenging adverse events such as osteoradionecrosis (ORN). A preclinical rabbit model of irradiated bone and ORN is herein proposed, with the aim to develop a viable model to be exploited for investigating new therapeutic approaches., Methods: Nine New Zealand white rabbits were irradiated using a single beam positioned to the left of the mandible and directed perpendicular to the left mandible. A 10 × 10 mm
2 region of interest (ROI) located below the first molar tooth on the left side was identified and irradiated with 7 Gy each fraction, once every 2 days, for five fractions. Dose distributions demonstrated that the corresponding ROI on the contralateral (right) mandibular side received approximately 5 Gy each fraction, thus bilateral irradiation of the mandible was achieved. ROIs were categorized as ROIH on the left side receiving the high dose and ROIL on the right side receiving the low dose. Rabbits were followed up clinically and imaged monthly. After 4 months, the irradiated bone was excised, and histological examination of ROIs was performed., Results: Radiological signs suggestive for ORN were detected in the entire population (100%) 16 weeks after irradiation on ROIH , which consisted of cortical erosion and loss of trabeculae. ROIL did not show any radiological evidence of bone damage. Histologically, both sides showed comparable signs of injury, with marked reduction in osteocyte count and increase in empty lacunae count., Conclusions: A preclinical double model was successfully developed. The side receiving the higher dose showed radiological and histological signs of bone damage, resulting in an ORN model. Whereas the contralateral side, receiving the lower dose, presented with histological damage only and a normal radiological appearance. This work describes the creation of a double model, an ORN and irradiated bone model, for further study using this animal species., (Head & Neck© 2024 The Author(s). Head & Neck published by Wiley Periodicals LLC.)- Published
- 2024
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11. Does Freehand, Patient-specific Instrumentation or Surgical Navigation Perform Better for Allograft Reconstruction After Tumor Resection? A Preclinical Synthetic Bone Study.
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Chan HHL, Nayak P, Alshaygy I, Gundle KR, Tsoi K, Daly MJ, Irish JC, Ferguson PC, and Wunder JS
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- Humans, Cone-Beam Computed Tomography, Plastic Surgery Procedures methods, Plastic Surgery Procedures instrumentation, Patient-Specific Modeling, Workload, Radiographic Image Interpretation, Computer-Assisted, Bone Substitutes, Bone Transplantation methods, Bone Neoplasms surgery, Allografts, Surgery, Computer-Assisted instrumentation, Surgery, Computer-Assisted methods
- Abstract
Background: Joint-sparing resection of periarticular bone tumors can be challenging because of complex geometry. Successful reconstruction of periarticular bone defects after tumor resection is often performed with structural allografts to allow for joint preservation. However, achieving a size-matched allograft to fill the defect can be challenging because allograft sizes vary, they do not always match a patient's anatomy, and cutting the allograft to perfectly fit the defect is demanding., Questions/purposes: (1) Is there a difference in mental workload among the freehand, patient-specific instrumentation, and surgical navigation approaches? (2) Is there a difference in conformance (quantitative measure of deviation from the ideal bone graft), elapsed time during reconstruction, and qualitative assessment of goodness-of-fit of the allograft reconstruction among the approaches?, Methods: Seven surgeons used three modalities in the same order (freehand, patient-specific instrumentation, and surgical navigation) to fashion synthetic bone to reconstruct a standardized bone defect. National Aeronautics and Space Administration (NASA) mental task load index questionnaires and procedure time were captured. Cone-beam CT images of the shaped allografts were used to measure conformance (quantitative measure of deviation from the ideal bone graft) to a computer-generated ideal bone graft model. Six additional (senior) surgeons blinded to modality scored the quality of fit of the allografts into the standardized tumor defect using a 10-point Likert scale. We measured conformance using the root-mean-square metric in mm and used ANOVA for multipaired comparisons (p < 0.05 was significant)., Results: There was no difference in mental NASA total task load scores among the freehand, patient-specific instrumentation, and surgical navigation techniques. We found no difference in conformance root-mean-square values (mean ± SD) between surgical navigation (2 ± 0 mm; mean values have been rounded to whole numbers) and patient-specific instrumentation (2 ± 1 mm), but both showed a small improvement compared with the freehand approach (3 ± 1 mm). For freehand versus surgical navigation, the mean difference was 1 mm (95% confidence interval [CI] 0.5 to 1.1; p = 0.01). For freehand versus patient-specific instrumentation, the mean difference was 1 mm (95% CI -0.1 to 0.9; p = 0.02). For patient-specific instrumentation versus surgical navigation, the mean difference was 0 mm (95% CI -0.5 to 0.2; p = 0.82). In evaluating the goodness of fit of the shaped grafts, we found no clinically important difference between surgical navigation (median [IQR] 7 [6 to 8]) and patient-specific instrumentation (median 6 [5 to 7.8]), although both techniques had higher scores than the freehand technique did (median 3 [2 to 4]). For freehand versus surgical navigation, the difference of medians was 4 (p < 0.001). For freehand versus patient-specific instrumentation, the difference of medians was 3 (p < 0.001). For patient-specific instrumentation versus surgical navigation, the difference of medians was 1 (p = 0.03). The mean ± procedural times for freehand was 16 ± 10 minutes, patient-specific instrumentation was 14 ± 9 minutes, and surgical navigation techniques was 24 ± 8 minutes. We found no differences in procedure times across three shaping modalities (freehand versus patient-specific instrumentation: mean difference 2 minutes [95% CI 0 to 7]; p = 0.92; freehand versus surgical navigation: mean difference 8 minutes [95% CI 0 to 20]; p = 0.23; patient-specific instrumentation versus surgical navigation: mean difference 10 minutes [95% CI 1 to 19]; p = 0.12)., Conclusion: Based on surgical simulation to reconstruct a standardized periarticular bone defect after tumor resection, we found a possible small advantage to surgical navigation over patient-specific instrumentation based on qualitative fit, but both techniques provided slightly better conformance of the shaped graft for fit into the standardized post-tumor resection bone defect than the freehand technique did. To determine whether these differences are clinically meaningful requires further study. The surgical navigation system presented here is a product of laboratory research development, and although not ready to be widely deployed for clinical practice, it is currently being used in a research operating room setting for patient care. This new technology is associated with a learning curve, capital costs, and potential risk. The reported preliminary results are based on a preclinical synthetic bone tumor study, which is not as realistic as actual surgical scenarios., Clinical Relevance: Surgical navigation systems are an emerging technology in orthopaedic and reconstruction surgery, and understanding their capabilities and limitations is paramount for clinical practice. Given our preliminary findings in a small cohort study with one scenario of standardized synthetic periarticular bone tumor defects, future investigations should include different surgical scenarios using allograft and cadaveric specimens in a more realistic surgical setting., Competing Interests: Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Association of Bone and Joint Surgeons.)
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- 2024
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12. Indocyanine green fluorescence quantification during normothermic ex situ perfusion for the assessment of porcine liver grafts after circulatory death.
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Goto T, Noguchi Y, Linares I, Mazilescu L, Nogueira E, Hobeika C, Ray S, Parmentier C, Ganesh S, Peranantharuban J, Chan HHL, Reichman T, Selzner N, and Selzner M
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- Animals, Swine, Warm Ischemia adverse effects, Organ Preservation methods, Optical Imaging methods, Fluorescence, Hepatic Artery diagnostic imaging, Hepatic Artery surgery, Indocyanine Green administration & dosage, Liver Transplantation methods, Liver Transplantation adverse effects, Liver blood supply, Liver surgery, Liver diagnostic imaging, Perfusion methods
- Abstract
Current graft evaluation during normothermic ex situ liver perfusion lacks real-time parameters for predicting posttransplant hepatocyte and biliary function. Indocyanine green (ICG) imaging has been widely used in liver surgery, enabling the visualization of hepatic uptake and excretion through bile using near-infrared light. In this research, porcine livers under various ischemic conditions were examined during a 5-hour normothermic ex situ liver perfusion procedure, introducing ICG at 1 hour through the hepatic artery. These conditions included livers from heart-beating donors, donation after circulatory death (DCD) with warm ischemic durations of 60 minutes (DCD60) and 120 minutes (DCD120), as well as interventions utilizing tissue plasminogen activator in DCD120 cases (each n = 5). Distinct hepatic fluorescence patterns correlated with different degrees of ischemic injury ( p = 0.01). Low ICG uptake in the parenchyma (less than 40% of maximum intensity) was more prevalent in DCD120 (21.4%) compared to heart-beating donors (6.2%, p = 0.06) and DCD60 (3.0%, p = 0.02). Moreover, ICG clearance from 60 minutes to 240 minutes was significantly higher in heart-beating donors (69.3%) than in DCD60 (17.5%, p < 0.001) and DCD120 (32.1%, p = 0.01). Furthermore, thrombolytic intervention using tissue plasminogen activator in DCD120 resulted in noteworthy outcomes, including significantly reduced ALP levels ( p = 0.04) and improved ICG clearance ( p = 0.02) with a trend toward mitigating fibrin deposition similar to DCD60, as well as enhancements in bile production ( p = 0.09). In conclusion, ICG fluorescence imaging during normothermic ex situ liver perfusion provides real-time classification of hepatic vascular and biliary injuries, offering valuable insights for the more accurate selection and postintervention evaluation of marginal livers in transplantation., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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13. Cryptococcal Meningitis With Immune-Reconstitution Inflammatory Syndrome Causing Papilledema and Visual Field Defects in an Immunocompetent Patient.
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Maccora KA, Tang YF, Lee JH, Chong EW, and Chan HHL
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- Humans, Immunocompetence, Male, Magnetic Resonance Imaging, Vision Disorders etiology, Vision Disorders diagnosis, Adult, Meningitis, Cryptococcal complications, Meningitis, Cryptococcal diagnosis, Papilledema diagnosis, Papilledema etiology, Visual Fields physiology, Immune Reconstitution Inflammatory Syndrome complications, Immune Reconstitution Inflammatory Syndrome diagnosis
- Abstract
Competing Interests: The authors report no conflicts of interest.
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- 2024
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14. Evaluation of a Novel Dermal Cooling System for the Treatment of Benign Pigmented Lesions in Asians.
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Wong CSM, Chan MWM, Shek SYN, Yeung CK, and Chan HHL
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- Humans, Female, Male, Adult, Prospective Studies, Middle Aged, Young Adult, Treatment Outcome, Cryotherapy instrumentation, Cryotherapy methods, Adolescent, Aged, Follow-Up Studies, Asian People, Pigmentation Disorders therapy
- Abstract
Objective: Our study aimed to evaluate the efficacy of this novel dermal cooling system (DCS) in reducing pigmentation in benign pigmented lesions in Asian patients and its potential side effects., Methods: It was a prospective open-label single-center study. Asian patients, with the presence of benign pigmented lesions mainly including lentigines, melasma, nevus spilus, ephelides, café au lait, and seborrheic keratosis were recruited for a novel DCS. The DCS provided localized cooling of the epidermal layer below freezing but was less intense than cryotherapy. Each patient received DCS at Week 0 and repeated at 4-week intervals up to 10 sessions. Global aesthetic improvement scores (GAIS) by blinded physicians and subjects were recorded at 2, 6, and 12 months posttreatment follow-up., Results: Eighty-one patients were recruited with a total of 305 sessions performed and 1716 lesion sites treated. At 2-month posttreatment, 76.5% and 58.6% treatment sites showed obvious to marked improvement respectively and the improvement sustained at 6 and 12 months. Only minor adverse events were reported. Erythema and edema were the most commonly anticipated effects immediately after treatment. The pain was minimal. Postinflammatory hyperpigmentation was only reported in 2.2% (38/1716) treated sites., Conclusion: To our knowledge, this study was the first study to demonstrate that this novel DCS was an effective, safe, and well-tolerated treatment for benign pigmented lesions in Asians., (© 2024 Wiley Periodicals LLC.)
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- 2024
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15. Hydrogel-chitosan and polylactic acid-polycaprolactone bioengineered scaffolds for reconstruction of mandibular defects: a preclinical in vivo study with assessment of translationally relevant aspects.
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Ferrari M, Taboni S, Chan HHL, Townson J, Gualtieri T, Franz L, Ruaro A, Mathews S, Daly MJ, Douglas CM, Eu D, Sahovaler A, Muhanna N, Ventura M, Dey K, Pandini S, Pasini C, Re F, Bernardi S, Bosio K, Mattavelli D, Doglietto F, Joshi S, Gilbert RW, Nicolai P, Viswanathan S, Sartore L, Russo D, and Irish JC
- Abstract
Background: Reconstruction of mandibular bone defects is a surgical challenge, and microvascular reconstruction is the current gold standard. The field of tissue bioengineering has been providing an increasing number of alternative strategies for bone reconstruction. Methods: In this preclinical study, the performance of two bioengineered scaffolds, a hydrogel made of polyethylene glycol-chitosan (HyCh) and a hybrid core-shell combination of poly (L-lactic acid)/poly ( ε -caprolactone) and HyCh (PLA-PCL-HyCh), seeded with different concentrations of human mesenchymal stromal cells (hMSCs), has been explored in non-critical size mandibular defects in a rabbit model. The bone regenerative properties of the bioengineered scaffolds were analyzed by in vivo radiological examinations and ex vivo radiological, histomorphological, and immunohistochemical analyses. Results: The relative density increase (RDI) was significantly more pronounced in defects where a scaffold was placed, particularly if seeded with hMSCs. The immunohistochemical profile showed significantly higher expression of both VEGF-A and osteopontin in defects reconstructed with scaffolds. Native microarchitectural characteristics were not demonstrated in any experimental group. Conclusion: Herein, we demonstrate that bone regeneration can be boosted by scaffold- and seeded scaffold-reconstruction, achieving, respectively, 50% and 70% restoration of presurgical bone density in 120 days, compared to 40% restoration seen in spontaneous regeneration. Although optimization of the regenerative performance is needed, these results will help to establish a baseline reference for future experiments., Competing Interests: Some of the following authors (LS, DR, SP, PN, MF, RG, and JI) declare the present patents, but declare no other financial or non-financial competing interests: LS, DR., SP, PN, MF, RG, JI “Integrated core-shell bioactive structure for the regeneration of bone and osteochondral tissues” licensed to PCT: WO2022009126 (2022); priority IT20200016579 (2020). LS, DR, PG, KD, Salmeron-Sanchez M., Borsani E. “Tridimensional bioactive porous body for bone tissue regeneration and process for its preparation “licensed to ”PCT: WO2022009125 (2022); priority: IT20200016576 (2020). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Ferrari, Taboni, Chan, Townson, Gualtieri, Franz, Ruaro, Mathews, Daly, Douglas, Eu, Sahovaler, Muhanna, Ventura, Dey, Pandini, Pasini, Re, Bernardi, Bosio, Mattavelli, Doglietto, Joshi, Gilbert, Nicolai, Viswanathan, Sartore, Russo and Irish.)
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- 2024
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16. A review of the topical management of acne and its associated sequelae in the Asia-Pacific region with a spotlight on trifarotene.
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See JA, Chavda R, Kon KM, Goodman GJ, Oblepias MS, Nadela RE, Oon HH, Aurangabadkar S, Suh DH, Chan HHL, and Lahiri K
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- Humans, Asia, Hyperpigmentation etiology, Hyperpigmentation drug therapy, Administration, Cutaneous, Cicatrix etiology, Cicatrix drug therapy, Practice Guidelines as Topic, Skin Care methods, Erythema drug therapy, Erythema etiology, Acne Vulgaris drug therapy, Acne Vulgaris complications, Dermatologic Agents administration & dosage, Dermatologic Agents therapeutic use, Dermatologic Agents adverse effects, Retinoids administration & dosage, Retinoids therapeutic use, Retinoids adverse effects
- Abstract
Acne, a highly prevalent skin disease, can be particularly bothersome for patients of Asian background because of its impact on self-confidence and social interactions. In addition to active acne lesions, some patients may develop sequelae such as scarring, macular/postinflammatory hyperpigmentation, or erythema. The tendency of Asian skin to develop sequelae because of its increased susceptibility to irritation, cultural preferences for lighter skin phototypes, and differences in skincare regimens may all contribute to the increased burden of acne. Moreover, many Asia-Pacific countries do not have their own guidelines for acne management, and those that do often have no schedule in place for regular updates. In this article, we provide a critical review of the published guidance for the management of acne and its sequelae in the Asia-Pacific region, identifying gaps in current recommendations that could be addressed to enhance standards of acne care in Asia-Pacific countries. Along with highlighting the importance of a comprehensive skincare regimen to increase treatment efficacy and adherence, we discuss topical retinoids and retinoid combination options in the acne armamentarium that may be beneficial for sequelae prevention and management, such as adapalene 0.3% ± benzoyl peroxide 2.5%, tretinoin 0.05%, tazarotene 0.1%, and trifarotene 0.005%. In particular, trifarotene 0.005% has been observed to significantly reduce acne scar counts in a Phase 4 study. The recent data highlight the need to establish up-to-date guidance for acne and acne sequelae management in Asia-Pacific countries to provide optimal care to Asian patients., (© 2024 Galderma and The Authors. International Journal of Dermatology published by Wiley Periodicals LLC on behalf of the International Society of Dermatology.)
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- 2024
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17. A 3D Analysis of Plating Strategies in Mandibular Reconstruction: A Randomized Control Pilot Study.
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Chen T, Chan HHL, de Almeida J, Goldstein DP, Gilbert RW, Yao CMKL, Irish JC, and Davies JC
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- Humans, Middle Aged, Fibula surgery, Mandible diagnostic imaging, Mandible surgery, Pilot Projects, Tomography, X-Ray Computed, Aged, Free Tissue Flaps surgery, Mandibular Reconstruction methods, Surgery, Computer-Assisted methods
- Abstract
Objective(s): The purpose of this study was to compare computer-assisted mandibular plating to conventional plating using quantitative metrics., Methods: Patients scheduled to undergo mandibular reconstruction were randomized to three-dimensional modelling for preoperative plate bending or intraoperative freehand bending. Preoperative and postoperative head and neck computed tomography scans were obtained to generate computer models of the reconstruction. The overall plate surface contact area, mean plate-to-bone distance, degree of conformance, and position of the condylar head within the glenoid fossa between pre- and post-operative scans were calculated., Results: Twenty patients were included with a mean age of 57.8 years (standard deviation [SD] = 13.6). The mean follow-up time was 9.8 months (range = 1.6-22.3). Reconstruction was performed with fibular (25%) or scapular free flaps (75%). The percentage of surface contact between the reconstructive plate and mandible was improved with three-dimensional models compared to freehand bending (93.9 ± 7.7% vs. 78.0 ± 19.9%, p = 0.04). There was improved overall plate-to-bone distance (3D model: 0.7 ± 0.31 mm vs. conventional: 1.3 ± 0.8 mm, p = 0.06). Total intraoperative time was non-significantly decreased with the use of a model (3D model: 726.5 ± 89.1 min vs. conventional: 757.3 ± 84.1 min, p = 0.44). There were no differences in condylar head position or postoperative complications., Conclusion: Computer-assisted mandibular plating can be used to improve the accuracy of plate contouring., Level of Evidence: 2 Laryngoscope, 134:2182-2186, 2024., (© 2023 The American Laryngological, Rhinological and Otological Society, Inc.)
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- 2024
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18. Detection of significant liver fibrosis in Chinese psoriasis patients receiving methotrexate: a comparison between transient elastography and liver histology.
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Wong CSM, Mak LLY, Lee VKH, Lo RCL, Chung MMH, Chu F, Yeung CK, Yuen MF, and Chan HHL
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- Adult, Aged, Female, Humans, Male, Middle Aged, Biopsy, Dermatologic Agents therapeutic use, Dermatologic Agents adverse effects, Dermatologic Agents administration & dosage, East Asian People, Liver pathology, Liver diagnostic imaging, ROC Curve, Elasticity Imaging Techniques methods, Liver Cirrhosis diagnostic imaging, Liver Cirrhosis pathology, Methotrexate adverse effects, Methotrexate therapeutic use, Methotrexate administration & dosage, Psoriasis drug therapy, Psoriasis complications, Psoriasis pathology
- Abstract
Introduction: Methotrexate (MTX) is effective for treating psoriasis and psoriatic arthritis, but its potential hepatoxicity remains a concern. Liver biopsy, the gold standard for detecting MTX-induced liver injury, is invasive and carries considerable risk. Transient elastography (TE) offers a non-invasive alternative for detecting advanced liver fibrosis. This study investigated the performance of TE in detecting MTX-induced liver fibrosis among Chinese psoriasis patients, compared with liver biopsy., Methods: This study included adult patients with clinical psoriasis. Liver stiffness measurement using TE was performed in patients receiving MTX. Exclusion criteria were known liver cirrhosis, positive viral hepatitis carrier status, or conditions influencing TE performance. Liver biopsy was performed when liver stiffness was ≥7.1 kilopascals (kPa) or when the total cumulative dose (TCD) of MTX was ≥3.5 g., Results: A total of 228 patients were screened; among 34 patients who met the inclusion criteria, nine (26.5%) had significant liver fibrosis (Roenigk grade ≥3a). The area under the receiver operating characteristic curve was 0.76 (95% confidence interval=0.59-0.93; P=0.021), indicating that TE had satisfactory performance in detecting liver fibrosis. A cut-off value of 7.1 kPa of liver stiffness yielded 100% sensitivity and 68% specificity. Liver fibrosis was not correlated with the TCD of MTX or the duration of MTX use; it was significantly correlated with obesity and diabetes status (body mass index ≥30 kg/m
2 , waist circumference ≥138 cm, and glycated haemoglobin level ≥7.8%)., Conclusion: Transient elastography is reliable and superior to the TCD for detecting liver fibrosis in Chinese psoriasis patients receiving MTX. Liver biopsy should be reserved for high-risk patients or patients with liver stiffness ≥11.7 kPa on TE., Competing Interests: All authors have disclosed no conflicts of interest.- Published
- 2024
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19. Wavelength-dependent threshold fluences for melanosome disruption to evaluate the treatment of pigmented lesions with 532-, 730-, 755-, 785-, and 1064-nm picosecond lasers.
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Shimojo Y, Nishimura T, Tsuruta D, Ozawa T, Chan HHL, and Kono T
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- Animals, Swine, Lasers, Skin radiation effects, Treatment Outcome, Melanosomes radiation effects, Lasers, Solid-State therapeutic use
- Abstract
Background and Objectives: A threshold fluence for melanosome disruption has the potential to provide a robust numerical indicator for establishing clinical endpoints for pigmented lesion treatment using a picosecond laser. Although the thresholds for a 755-nm picosecond laser were previously reported, the wavelength dependence has not been investigated. In this study, wavelength-dependent threshold fluences for melanosome disruption were determined. Using a mathematical model based on the thresholds, irradiation parameters for 532-, 730-, 755-, 785-, and 1064-nm picosecond laser treatments were evaluated quantitatively., Study Design/materials and Methods: A suspension of melanosomes extracted from porcine eyes was irradiated using picosecond lasers with varying fluence. The mean particle size of the irradiated melanosomes was measured by dynamic light scattering, and their disruption was observed by scanning electron microscopy to determine the disruption thresholds. A mathematical model was developed, combined with the threshold obtained and Monte Carlo light transport to calculate irradiation parameters required to disrupt melanosomes within the skin tissue., Results: The threshold fluences were determined to be 0.95, 2.25, 2.75, and 6.50 J/cm² for 532-, 730-, 785-, and 1064-nm picosecond lasers, respectively. The numerical results quantitatively revealed the relationship between irradiation wavelength, incident fluence, and spot size required to disrupt melanosomes distributed at different depths in the skin tissue. The calculated irradiation parameters were consistent with clinical parameters that showed high efficacy with a low incidence of complications., Conclusion: The wavelength-dependent thresholds for melanosome disruption were determined. The results of the evaluation of irradiation parameters from the threshold-based analysis provided numerical indicators for setting the clinical endpoints for 532-, 730-, 755-, 785-, and 1064-nm picosecond lasers., (© 2024 Wiley Periodicals LLC.)
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- 2024
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20. Nanoparticle-mediated Photodynamic Therapy as a Method to Ablate Oral Cavity Squamous Cell Carcinoma in Preclinical Models.
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Sahovaler A, Valic MS, Townson JL, Chan HHL, Zheng M, Tzelnick S, Mondello T, Pener-Tessler A, Eu D, El-Sayes A, Ding L, Chen J, Douglas CM, Weersink R, Muhanna N, Zheng G, and Irish JC
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- Humans, Animals, Rabbits, Mice, Photosensitizing Agents pharmacology, Squamous Cell Carcinoma of Head and Neck chemically induced, Photochemotherapy methods, Carcinoma, Squamous Cell drug therapy, Mouth Neoplasms drug therapy, Head and Neck Neoplasms chemically induced, Nanoparticles therapeutic use, Organothiophosphorus Compounds
- Abstract
Photodynamic therapy (PDT) is a tissue ablation technique able to selectively target tumor cells by activating the cytotoxicity of photosensitizer dyes with light. PDT is nonsurgical and tissue sparing, two advantages for treatments in anatomically complex disease sites such as the oral cavity. We have previously developed PORPHYSOME (PS) nanoparticles assembled from chlorin photosensitizer-containing building blocks (∼94,000 photosensitizers per particle) and capable of potent PDT. In this study, we demonstrate the selective uptake and curative tumor ablation of PS-enabled PDT in three preclinical models of oral cavity squamous cell carcinoma (OCSCC): biologically relevant subcutaneous Cal-33 (cell line) and MOC22 (syngeneic) mouse models, and an anatomically relevant orthotopic VX-2 rabbit model. Tumors selectively uptake PS (10 mg/kg, i.v.) with 6-to 40-fold greater concentration versus muscle 24 hours post-injection. Single PS nanoparticle-mediated PDT (PS-PDT) treatment (100 J/cm2, 100 mW/cm2) of Cal-33 tumors yielded significant apoptosis in 65.7% of tumor cells. Survival studies following PS-PDT treatments demonstrated 90% (36/40) overall response rate across all three tumor models. Complete tumor response was achieved in 65% of Cal-33 and 91% of MOC22 tumor mouse models 14 days after PS-PDT, and partial responses obtained in 25% and 9% of Cal-33 and MOC22 tumors, respectively. In buccal VX-2 rabbit tumors, combined surface and interstitial PS-PDT (200 J total) yielded complete responses in only 60% of rabbits 6 weeks after a single treatment whereas three repeated weekly treatments with PS-PDT (200 J/week) achieved complete ablation in 100% of tumors. PS-PDT treatments were well tolerated by animals with no treatment-associated toxicities and excellent cosmetic outcomes., Significance: PS-PDT is a safe and repeatable treatment modality for OCSCC ablation. PS demonstrated tumor selective uptake and PS-PDT treatments achieved reproducible efficacy and effectiveness in multiple tumor models superior to other clinically tested photosensitizer drugs. Cosmetic and functional outcomes were excellent, and no clinically significant treatment-associated toxicities were detected. These results are enabling of window of opportunity trials for fluorescence-guided PS-PDT in patients with early-stage OCSCC scheduled for surgery., (© 2024 The Authors; Published by the American Association for Cancer Research.)
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- 2024
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21. The use of fractional radiofrequency in Asian patients to improve skin texture.
- Author
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Chan MWM, Chan AWS, Wong CSM, Shek SYN, Yeung CK, Kono T, and Chan HHL
- Subjects
- Humans, Asian People, Prospective Studies, Skin pathology, Treatment Outcome, Young Adult, Adult, Middle Aged, Acne Vulgaris radiotherapy, Cicatrix therapy
- Abstract
Background and Objectives: Fractional radiofrequency devices have been demonstrated to improve skin texture, such as smoothness, rhytides, brightness, and atrophic acne scars, by increasing dermal thickness, dermal collagen content, and dermal fibrillin content. The objective of the study is to assess the efficacy and adverse effects of this device on Asian patients of skin type III and IV with skin textural changes., Materials and Methods: The study was designed as a prospective, open-labeled single-arm study, which was conducted with 20 Chinese patients aged 21-60 years and having irregularities in their skin texture, rhytides, and acne scars. The patients received six treatments at intervals of 4 weeks. Treatment was initiated with the maximum energy tolerated, which was then adjusted during the course of treatment if the patients felt excessive discomfort. A total of two passes were delivered in each session. Physician assessment results and standardized photographs were collected at the baseline, after all treatment visits, and at 1, 2, and 6 months after the final treatment visit., Results: A total of 17 patients completed the study according to the established protocol. At the 6-month follow-up, 71% of patients were satisfied and 24% of patients were very satisfied with the received treatments, and the treatment physician reported varying degrees of improvement based on the global assessment scale in 60% of the subjects. While the anticipated side effects, such as erythema, edema, pinpoint bleeding, scab formation, and flare of acne, were noted in the patients, no serious adverse effects occurred., Conclusion: The use of fractional radiofrequency improves skin texture and is safe for use in Asian patients of skin type III and IV. No long-term serious adverse effects were noted., (© 2024 Wiley Periodicals LLC.)
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- 2024
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22. The effect of montages of transcranial alternating current stimulation on occipital responses-a sham-controlled pilot study.
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Wang J, Choi KY, Thompson B, Chan HHL, and Cheong AMY
- Abstract
Background: Transcranial alternative current stimulation (tACS) refers to a promising non-invasive technique to improve brain functions. However, owing to various stimulation parameters in the literature, optimization of the stimulation is warranted. In this study, the authors aimed to compare the effect of tACS electrode montages on occipital responses., Methods: In three montage sessions (i.e., Oz-Cz, Oz-cheek, and sham), 10 healthy young adults participated, receiving 20-min 2-mA alpha-tACS. Pattern-reversal visual evoked potentials (VEPs) were measured before tACS (T0), immediately after (T20), and 20 min (T40) after tACS. Normalized changes in time-domain features (i.e., N75, P100 amplitudes, and P100 latency) and frequency-domain features [i.e., power spectral density in alpha (PSDα) and beta (PSDβ) bands] were evaluated., Results: In contrast to our hypothesis, the occipital response decreased immediately (T20) after receiving the 20-min tACS in all montages in terms of P100 amplitude ( p = 0.01). This reduction returned to baseline level (T0) in Oz-cheek and sham conditions but sustained in the Oz-Cz condition (T40, p = 0.03) after 20 min of tACS. The effects on N75 amplitude and P100 latency were statistically insignificant. For spectral analysis, both PSDα and PSDβ were significantly increased after tACS at T20, in which the effect sustained until T40. However, there was no differential effect by montages. There was no significant difference in the occurrence of sensations across the montages. The effectiveness of the blinding is supported by the participants' rate of guessing correctly., Conclusion: This study revealed an immediate inhibitory effect of tACS, regardless of the montages. This inhibitory effect sustained in the Oz-Cz montage but faded out in other montages after 20 min., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Wang, Choi, Thompson, Chan and Cheong.)
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- 2024
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23. Cutaneous manifestations, viral load, and prognosis among hospitalised patients with COVID-19: a cohort study.
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Wong CSM, Hung IFN, Kwan MYW, Chung MMH, Chan MWM, Cheng AKC, Lau YM, Yeung CK, Chan HHL, and Lau CS
- Subjects
- Adult, Humans, SARS-CoV-2, Cohort Studies, Viral Load, Retrospective Studies, Prognosis, COVID-19 complications, Exanthema
- Abstract
Introduction: Various cutaneous manifestations have been reported as symptoms of coronavirus disease 2019 (COVID-19), which may facilitate early clinical diagnosis and management. This study explored the incidence of cutaneous manifestations among hospitalised patients with COVID-19 and investigated its relationships with viral load, co-morbidities, and outcomes., Methods: This retrospective study included adult patients admitted to a tertiary hospital for COVID-19 from July to September 2020. Clinical information, co-morbidities, viral load (cycle threshold [Ct] value), and outcomes were analysed., Results: In total, 219 patients with confirmed COVID-19 were included. Twenty patients presented with new onset of rash. The incidence of new rash was 9.1% (95% confidence interval=6.25%-14.4%). The most common manifestations were maculopapular exanthem (n=6, 42.9%, median Ct value: 24.8), followed by livedo reticularis (n=4, 28.6%, median Ct value: 21.3), varicella-like lesions (n=2, 14.3%, median Ct value: 19.3), urticaria (n=1, 7.1%, median Ct value: 14.4), and acral chilblain and petechiae (n=1, 7.1%, median Ct value: 33.1). The median Ct values for patients with and without rash were 22.9 and 24.1, respectively (P=0.58). There were no significant differences in mortality or hospital stay between patients with and without rash. Patients with rash were more likely to display fever on admission (P<0.01). Regardless of cutaneous manifestations, patients with older age, hypertension, and chronic kidney disease stage ≥3 had significantly higher viral load and mortality (P<0.05)., Conclusion: This study revealed no associations between cutaneous manifestation and viral load or clinical outcomes. Older patients with multiple co-morbidities have risks of high viral load and mortality; they should be closely monitored., Competing Interests: All authors declare no conflicts of interest.
- Published
- 2023
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24. A total inverse planning paradigm: Prospective clinical trial evaluating the performance of a novel MR-based 3D-printed head immobilization device.
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Jablonska PA, Parent A, La Macchia N, Chan HHL, Filleti M, Ramotar M, Cho YB, Braganza M, Badzynski A, Laperriere N, Conrad T, Tsang DS, Shultz D, Santiago A, Irish JC, Millar BA, Tadic T, and Berlin A
- Abstract
Background and Purpose: Brain radiotherapy (cnsRT) requires reproducible positioning and immobilization, attained through redundant dedicated imaging studies and a bespoke moulding session to create a thermoplastic mask (T-mask). Innovative approaches may improve the value of care. We prospectively deployed and assessed the performance of a patient-specific 3D-printed mask (3Dp-mask), generated solely from MR imaging, to replicate a reproducible positioning and tolerable immobilization for patients undergoing cnsRT., Material and Methods: Patients undergoing LINAC-based cnsRT (primary tumors or resected metastases) were enrolled into two arms: control (T-mask) and investigational (3Dp-mask). For the latter, an in-house designed 3Dp-mask was generated from MR images to recreate the head positioning during MR acquisition and allow coupling with the LINAC tabletop. Differences in inter-fraction motion were compared between both arms. Tolerability was assessed using patient-reported questionnaires at various time points., Results: Between January 2020 - July 2022, forty patients were enrolled (20 per arm). All participants completed the prescribed cnsRT and study evaluations. Average 3Dp-mask design and printing completion time was 36 h:50 min (range 12 h:56 min - 42 h:01 min). Inter-fraction motion analyses showed three-axis displacements comparable to the acceptable tolerance for the current standard-of-care. No differences in patient-reported tolerability were seen at baseline. During the last week of cnsRT, 3Dp-mask resulted in significantly lower facial and cervical discomfort and patients subjectively reported less pressure and confinement sensation when compared to the T-mask. No adverse events were observed., Conclusion: The proposed total inverse planning paradigm using a 3D-printed immobilization device is feasible and renders comparable inter-fraction performance while offering a better patient experience, potentially improving cnsRT workflows and its cost-effectiveness., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)
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- 2023
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25. Nanostructure-Driven Indocyanine Green Dimerization Generates Ultra-Stable Phototheranostics Nanoparticles.
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Kwon N, Jasinevicius GO, Kassab G, Ding L, Bu J, Martinelli LP, Ferreira VG, Dhaliwal A, Chan HHL, Mo Y, Bagnato VS, Kurachi C, Chen J, Zheng G, and Buzzá HH
- Subjects
- Mice, Animals, Indocyanine Green chemistry, Dimerization, Polymers, Phototherapy methods, Cell Line, Tumor, Nanoparticles chemistry, Nanostructures therapeutic use, Nanostructures chemistry
- Abstract
Indocyanine green (ICG) is the only near-infrared (NIR) dye approved for clinical use. Despite its versatility in photonic applications and potential for photothermal therapy, its photobleaching hinders its application. Here we discovered a nanostructure of dimeric ICG (Nano-dICG) generated by using ICG to stabilize nanoemulsions, after which ICG enabled complete dimerization on the nanoemulsion shell, followed by J-aggregation of ICG-dimer, resulting in a narrow, red-shifted (780 nm→894 nm) and intense (≈2-fold) absorbance. Compared to ICG, Nano-dICG demonstrated superior photothermal conversion (2-fold higher), significantly reduced photodegradation (-9.6 % vs. -46.3 %), and undiminished photothermal effect (7 vs. 2 cycles) under repeated irradiations, in addition to excellent colloidal and structural stabilities. Following intravenous injection, Nano-dICG enabled real-time tracking of its delivery to mouse tumors within 24 h by photoacoustic imaging at NIR wavelength (890 nm) distinct from the endogenous signal to guide effective photothermal therapy. The unprecedented finding of nanostructure-driven ICG dimerization leads to an ultra-stable phototheranostic platform., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
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- 2023
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26. Using augmented reality to guide bone conduction device implantation.
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Lui JT, Dahm V, Chen JM, Lin VY, Irish JC, Le TN, and Chan HHL
- Subjects
- Humans, Bone Conduction, Imaging, Three-Dimensional methods, Fiducial Markers, Augmented Reality, Surgery, Computer-Assisted methods
- Abstract
Exact placement of bone conduction implants requires avoidance of critical structures. Existing guidance technologies for intraoperative placement have lacked widespread adoption given accessibility challenges and significant cognitive loading. The purpose of this study is to examine the application of augmented reality (AR) guided surgery on accuracy, duration, and ease on bone conduction implantation. Five surgeons surgically implanted two different types of conduction implants on cadaveric specimens with and without AR projection. Pre- and postoperative computer tomography scans were superimposed to calculate centre-to-centre distances and angular accuracies. Wilcoxon signed-rank testing was used to compare centre-to-centre (C-C) and angular accuracies between the control and experimental arms. Additionally, projection accuracy was derived from the distance between the bony fiducials and the projected fiducials using image guidance coordinates. Both operative time (4.3 ± 1.2 min. vs. 6.6 ± 3.5 min., p = 0.030) and centre-to-centre distances surgery (1.9 ± 1.6 mm vs. 9.0 ± 5.3 mm, p < 0.001) were significantly less in augmented reality guided surgery. The difference in angular accuracy, however, was not significantly different. The overall average distance between the bony fiducial markings and the AR projected fiducials was 1.7 ± 0.6 mm. With direct intraoperative reference, AR-guided surgery enhances bone conduction implant placement while reduces operative time when compared to conventional surgical planning., (© 2023. The Author(s).)
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- 2023
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27. Myopia Control Efficacy and Long-Term Safety of a Novel Orthokeratology Lens (MESOK Study)-A Randomized Controlled Clinical Trial Combining Clinical and Tear Proteomics Data.
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Choi KY, Cheung JKW, Wong GTK, Li PH, Chan SSH, Lam TC, and Chan HHL
- Abstract
Myopia control efficacy and long-term safety of the Breath-O-Correct orthokeratology (OK) lens was evaluated in a 2-year randomized, single vision (SV) spectacle lens-controlled, single-blind clinical trial combining clinical and tear proteomics data. A total of 71 children (43 OK, 9.8 ± 1.3 years; 28 SV, 9.5 ± 1.4 years) completed the 2-year study. Axial length (AL), cycloplegic refraction, clinical safety parameters (best-corrected visual acuity, central cornea thickness, corneal endothelial health, ocular surface disease index), and quantitative tear proteomics were evaluated by masked examiners. Mean 2-year-normalized AL elongations in the OK and SV groups differed significantly ( p = 0.03) and were 0.37 ± 0.37 mm and 0.60 ± 0.41 mm, respectively. OK-mediated myopia control efficacy was 37.1%. No significant difference was found in clinical safety parameters of both groups ( p > 0.10), except for a thinner central corneal thickness in the OK group ( p = 0.01). Proteomics revealed modest OK lens-mediated effects on immune response proteins, including an increased abundance of haptoglobin at 6 and 12 months and a decreased abundance of two proteins (neutrophil defensin 3 and histone 4) at 6 months. The changes were further validated using a high-resolution multiple-reaction monitoring (MRM
HR ) mass spectrometry. In summary, the Breath-O-Correct OK lens significantly reduced AL elongation in schoolchildren without adverse clinical effects or subclinical inflammatory responses.- Published
- 2023
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28. Skull-Base Surgery-A Narrative Review on Current Approaches and Future Developments in Surgical Navigation.
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Tzelnick S, Rampinelli V, Sahovaler A, Franz L, Chan HHL, Daly MJ, and Irish JC
- Abstract
Surgical navigation technology combines patient imaging studies with intraoperative real-time data to improve surgical precision and patient outcomes. The navigation workflow can also include preoperative planning, which can reliably simulate the intended resection and reconstruction. The advantage of this approach in skull-base surgery is that it guides access into a complex three-dimensional area and orients tumors intraoperatively with regard to critical structures, such as the orbit, carotid artery and brain. This enhances a surgeon's capabilities to preserve normal anatomy while resecting tumors with adequate margins. The aim of this narrative review is to outline the state of the art and the future directions of surgical navigation in the skull base, focusing on the advantages and pitfalls of this technique. We will also present our group experience in this field, within the frame of the current research trends.
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- 2023
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29. One step forward to sustainability: The carbon footprint of cataract surgery in Australia.
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Hong Z, Chong EW, and Chan HHL
- Subjects
- Humans, Carbon Footprint, Australia epidemiology, Cataract Extraction, Lens, Crystalline, Cataract
- Published
- 2023
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30. Efficacy of 0.01% atropine for myopia control in a randomized, placebo-controlled trial depends on baseline electroretinal response.
- Author
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Chan HHL, Choi KY, Ng ALK, Choy BNK, Chan JCH, Chan SSH, Li SZC, and Yu WY
- Subjects
- Axial Length, Eye, Child, Disease Progression, Humans, Ophthalmic Solutions, Refraction, Ocular, Vision Tests, Atropine, Myopia drug therapy
- Abstract
This study aimed to evaluate the efficacy of 18-month 0.01% atropine in 61 myopic children (aged 7-10) and the relationship with central retinal response (by multifocal electroretinogram [mfERG]) in a double-masked randomized placebo-controlled clinical trial. Global-flash mfERG was measured at baseline, while cycloplegic spherical equivalent refraction (SER) and axial length (AL) were measured at baseline and at 6-month intervals. Annualized change in SER and AL were compared between atropine and control groups, and the relationships with baseline mfERG were evaluated. Changes in SER (-0.70 ± 0.39D vs. -0.66 ± 0.41D, p = 0.63) and AL (0.32 ± 0.16 mm vs. 0.30 ± 0.22 mm, p = 0.52) were similar in atropine and control groups. Interestingly, in the placebo group, mfERG amplitude was negatively correlated with axial elongation (R
p = -0.44, p = 0.03) as in our previous study. However, in the atropine group, an opposite trend was observed that axial elongation was positively correlated with mfERG amplitude (Ra = 0.37, p = 0.04). Annualized myopia progression demonstrated similar opposite effect between atropine and placebo groups but did not reach statistical significance. An ERG screening protocol may be warranted to identify suitable candidates to reduce the likelihood of an unfavorable treatment response by 0.01% atropine., (© 2022. The Author(s).)- Published
- 2022
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31. Preclinical evaluation of thin convex probe endobronchial ultrasound-guided transbronchial needle aspiration for intrapulmonary lesions.
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Ishiwata T, Inage T, Gregor A, Motooka Y, Chan HHL, Bernards N, Aragaki M, Chen Z, Ujiie H, Kinoshita T, Effat A, and Yasufuku K
- Abstract
Background: Conventional flexible bronchoscopy has not achieved the high diagnostic yield for intrapulmonary lesions as seen with image-guided transthoracic biopsy. A thin convex probe endobronchial ultrasound bronchoscope (TCP-EBUS) with a 5.9-mm tip was designed to improve peripheral access over conventional EBUS bronchoscopes to facilitate real-time sampling of intrapulmonary lesions under ultrasound guidance., Methods: TCP-EBUS was inserted into the distal airways of ex-vivo human lungs to assess bronchial accessibility relative to clinically available bronchoscopes. The short- (≤1 h) and medium-term (≤10 d) safety of TCP-EBUS insertion and EBUS-guided transbronchial needle aspiration (TBNA) using a 25-gauge needle were evaluated physiologically and radiologically in live pigs. TCP-EBUS-guided TBNA feasibility was assessed in-vivo with pig intrapulmonary pseudo-tumors and ex-vivo with resected human lung cancer specimens., Results: For bronchial accessibility, TCP-EBUS demonstrated greater reach than the 6.6-mm convex probe endobronchial ultrasound (CP-EBUS) in all bronchi, as well as surpassed a 5.5-mm conventional bronchoscope in 63% (131/209) and a 4.8-mm conventional bronchoscope in 27% (57/209) of assessed bronchi. The median bronchial generation and the mean diameter of bronchi TCP-EBUS reached was 4 (range, 3-7) and 3.3±0.7 mm, respectively. No major complications related to TCP-EBUS-guided TBNA in distal airways were observed in the live pigs. Scattered mucosal erythema of the bronchial walls was observed immediately after TCP-EBUS insertion; this self-resolved by day 10. TCP-EBUS could successfully reach and visualize intrapulmonary targets via ultrasound, with no difficulty in needle deployment or sampling., Conclusions: TCP-EBUS has the potential to facilitate safe real-time transbronchial sampling of intrapulmonary lesions in the central and middle lung fields., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-22-120/coif). KY reports support from the William Coco Chair in Surgical Innovation for Lung Cancer, during the conduct of this study; KY is a consultant for Olympus Medical Systems Corporation. The other authors have no conflicts of interest to declare., (2022 Translational Lung Cancer Research. All rights reserved.)
- Published
- 2022
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32. Development of a cadaveric head and neck cancer model and three-dimensional analysis of margins in surgical navigation-aided ablations.
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Ferrari M, Taboni S, Carobbio ALC, Buffoli B, Rampinelli V, Mattavelli D, Schreiber A, Verzeletti V, Ravanelli M, Daly MJ, Chan HHL, Sahovaler A, Franz L, Gualtieri T, Rezzani R, Maroldi R, Signoroni A, Deganello A, Irish JC, and Nicolai P
- Subjects
- Cadaver, Humans, Margins of Excision, Reproducibility of Results, Head and Neck Neoplasms surgery, Surgery, Computer-Assisted methods
- Abstract
Introduction: The adequacy of the surgical resection is the main controllable variable that is in the hands of the surgical team. There exists an unmet need to increase the rate of negative margins, particularly in cancers invading the craniofacial area. The study aimed 1) at developing a gross tumor model to be utilized for research, educational, and training purposes and 2) establishing the 3-dimensional relationship between the outer surface of the surgical specimen and tumor surface and test the effect of guiding ablations on cadavers with surgical navigation (SN)., Material and Methods: Seven cadaver heads were employed to create 24 craniofacial tumor models. Simulation of tumor resections was performed by 8 surgeons. Fourteen and 10 resections were performed with and without SN-guidance, respectively. Gross specimens underwent computed tomography and 3-dimensional analysis through dedicated software. Task load was assessed through a validated questionnaire. Tumor model reliability was studied based on visual analogue scale rate by surgeons and radiologists., Results: SN reduced the rate of margin involvement, particularly by decreasing the percentage of the gross specimen outer surface involvement in areas uncovered by normal bony structures. The workload of SN-aided ablations was found to be medium-to-somewhat-high. Tumor model reliability was deemed satisfactory except for the extension to bony structures., Conclusions: A gross tumor model for head and neck cancers involving the craniofacial area was developed and resulted satisfactorily reliable from both a surgical and radiologic standpoint. SN reduced the rate of margin involvement, particularly by improving delineation of bone-uncovered areas., (Copyright © 2021 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)
- Published
- 2022
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33. Selective blue-filtering spectacle lens protected primary porcine RPE cells against light emitting diode-induced cell damage.
- Author
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Yu WY, Shan SSW, Lakshmanan Y, Wong FSY, Choi KY, and Chan HHL
- Subjects
- Animals, Catalase, Cell Survival, Cells, Cultured, Reactive Oxygen Species metabolism, Swine, Eyeglasses, Trypan Blue
- Abstract
This study aimed to investigate whether use of a selective-blue-filtering (S-BF) lens can protect cultured primary porcine RPE cells against photo-irradiation. Transmittance of S-BF and UV-filtering (UVF) lenses was characterised spectrophotometrically. RPE cells were exposed to 1700 lux of white (peak λ at 443 and 533 nm; 0.44 mW/cm2) or blue (peak λ at 448 and 523 nm; 0.85 mW/cm2) LED light for 16 h to evaluate the influence of light source on the culture. The effect of the S-BF and UVF ophthalmic lenses on RPE cell cultures under blue light irradiation was then investigated. Cell viability was compared using trypan blue and MTT assays. Intracellular ROS production was detected by a fluorescein probe CM-H2DCFDA. Expression levels of catalase and Prdx3 were analysed by western blot. Trypan blue staining showed blue light caused more cell death than no light (p = 0.001) or white light (p = 0.005). MTT assay supported the hypothesis that exposure to blue light damaged RPE cells more severely than no light (p = 0.002) or white light (p = 0.014). Under blue light, use of the S-BF lens, which blocked 17% more blue light than the UVF lens, resulted in higher cellular viability (S-BF: 93.4±1.4% vs UVF: 90.6±1.4%; p = 0.022; MTT: 1.2-fold; p = 0.029). Blue and white light both significantly increased ROS production. The S-BF lens protected cells, resulting in lower levels of ROS and higher expression of catalase and Prdx3. To conclude, blue LED light exposure resulted in significant cytotoxicity to RPE cells. Partial blockage of blue light by an S-BF lens led to protective effects against retinal phototoxicity, which were mediated by reduction of ROS and increased levels of antioxidant enzymes., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2022
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34. Automatic Registration and Error Color Maps to Improve Accuracy for Navigated Bone Tumor Surgery Using Intraoperative Cone-Beam CT.
- Author
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Sahovaler A, Daly MJ, Chan HHL, Nayak P, Tzelnick S, Arkhangorodsky M, Qiu J, Weersink R, Irish JC, Ferguson P, and Wunder JS
- Abstract
Computer-assisted surgery (CAS) can improve surgical precision in orthopaedic oncology. Accurate alignment of the patient's imaging coordinates with the anatomy, known as registration, is one of the most challenging aspects of CAS and can be associated with substantial error. Using intraoperative, on-the-table, cone-beam computed tomography (CBCT), we performed a pilot clinical study to validate a method for automatic intraoperative registration., Methods: Patients who were ≥18 years of age, had benign bone tumors, and underwent resection were prospectively enrolled. In addition to inserting a navigation tracking tool into the exposed bone adjacent to the surgical field, 2 custom plastic ULTEM tracking tools (UTTs) were attached to each patient's skin adjacent to the tumor using an adhesive. These were automatically localized within the 3-dimensional CBCT volume to be used as image landmarks for registration, and the corresponding tracker landmarks were captured using an infrared camera. The main outcomes were the fiducial registration error (FRE) and the target registration error (TRE). The navigation time was recorded., Results: Thirteen patients with benign tumors in the femur (n = 10), tibia (n = 2), and humerus (n = 1) underwent navigation-assisted resections. The mean values were 0.67 ± 0.15 mm (range, 0.47 to 0.97 mm) for FRE and 0.83 ± 0.51 mm (range, 0.42 to 2.28 mm) for TRE. Registration was successful in all cases. The mean time for CBCT imaging and tracker registration was 7.5 minutes., Conclusions: We present a novel automatic registration method for CAS exploiting intraoperative CBCT capabilities, which provided improved accuracy and reduced operative times compared with more traditional methods., Clinical Relevance: This proof-of-principle study validated a novel process for automatic registration to improve the accuracy of resecting bone tumors using a surgical navigation system., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSOA/A386)., (Copyright © 2022 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)
- Published
- 2022
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35. Hybrid Core-Shell Polymer Scaffold for Bone Tissue Regeneration.
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Sartore L, Pasini C, Pandini S, Dey K, Ferrari M, Taboni S, Chan HHL, Townson J, Viswanathan S, Mathews S, Gilbert RW, Irish JC, Re F, Nicolai P, and Russo D
- Subjects
- Bone Regeneration, Bone and Bones, Polyesters chemistry, Tissue Engineering methods, Polymers, Tissue Scaffolds chemistry
- Abstract
A great promise for tissue engineering is represented by scaffolds that host stem cells during proliferation and differentiation and simultaneously replace damaged tissue while maintaining the main vital functions. In this paper, a novel process was adopted to develop composite scaffolds with a core-shell structure for bone tissue regeneration, in which the core has the main function of temporary mechanical support, and the shell enhances biocompatibility and provides bioactive properties. An interconnected porous core was safely obtained, avoiding solvents or other chemical issues, by blending poly(lactic acid), poly(ε-caprolactone) and leachable superabsorbent polymer particles. After particle leaching in water, the core was grafted with a gelatin/chitosan hydrogel shell to create a cell-friendly bioactive environment within its pores. The physicochemical, morphological, and mechanical characterization of the hybrid structure and of its component materials was carried out by means of infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and mechanical testing under different loading conditions. These hybrid polymer devices were found to closely mimic both the morphology and the stiffness of bones. In addition, in vitro studies showed that the core-shell scaffolds are efficiently seeded by human mesenchymal stromal cells, which remain viable, proliferate, and are capable of differentiating towards the osteogenic phenotype if adequately stimulated.
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- 2022
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36. The Feasibility of Eustachian Tube Dilation With a Standard Endovascular Balloon: A Comparative Cadaver Study.
- Author
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Dahm V, Chan HHL, Daly MJ, Lui JT, Lin VY, Irish J, Chen JM, and Le TN
- Subjects
- Cadaver, Dilatation methods, Feasibility Studies, Humans, Ear Diseases surgery, Eustachian Tube surgery
- Abstract
Background: Balloon dilation of the eustachian tube is a new therapeutic option for eustachian tube dysfunction. One of the limiting factors of wider adoption of this technique in many parts of the world is the high cost of the devices, in spite of regulatory approval of safety., Objective: Evaluate the performance and usability of standard less-expensive endovascular balloons for eustachian tube dilation in comparison to an approved device in a preclinical study., Study Design: Comparative cadaver feasibility study., Setting: University tertiary care facility., Methods: Ten eustachian tube dilations were performed with an approved eustachian tube dilation device. Ten other procedures were carried out with an endovascular balloon of similar dimensions. Cone beam computerized tomography was performed to evaluate the extent of dilation and possible damages. The lumen and mucosal lining were inspected endoscopically post-dilation. Volume measurements were compared before and after the procedure in both groups using contrast enhancement., Results: All 20 eustachian tube dilations were carried out successfully. No tissue damages could be identified on cone-beam computerized tomography or via endoscopic examination. There was a statistically significant difference of eustachian tube volumes between pre- and post-dilations, with no statistically significant difference between the devices., Conclusion: Eustachian tube dilation with a less costly endovascular balloon achieved similar results to an approved eustachian tube dilation device. No damages or any other safety concerns were identified in a cadaver study., Competing Interests: The authors disclose no conflicts of interest., (Copyright © 2021, Otology & Neurotology, Inc.)
- Published
- 2022
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37. Development of a minimally invasive pulmonary porcine embolism model via endobronchial ultrasound.
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Inage T, Fujino K, Motooka Y, Ishiwata T, Ujiie H, Gregor A, Bernards N, Chan HHL, Chen Z, Aragaki M, Kinoshita T, Effat A, Yoshino I, and Yasufuku K
- Abstract
Background: Current massive pulmonary embolism (PE) animal models use central venous access to deliver blood clots, which have features of random clot distribution and potentially fatal hemodynamic compromise. A clinically relevant preclinical model for generating pulmonary emboli in a more controlled fashion would be of value for a variety of research studies, including initial evaluation of novel therapeutic approaches. Endobronchial ultrasound-guided transbronchial needle injection (EBUS-TBNI) is a newly established approach for peri-tracheal/bronchial targets. The purpose of the present work was to establish a minimally invasive PE model in swine via a transbronchial approach., Methods: In anesthetized Yorkshire pigs, a 21-G EBUS-guided transbronchial needle aspiration (EBUS-TBNA) needle was introduced into the pulmonary artery under EBUS guidance. Autologous blood clots were administered into the right and left lower pulmonary arteries sequentially (PE1 and PE2, respectively). Hemodynamic and biochemical responses were evaluated., Results: Ten pigs were evaluated; all 20 blood clots (6.3±1.9 mL) were successfully injected. After injection, mean pulmonary artery pressure (mPAP; mmHg) increased (baseline: 16.6±5.6 vs. PE1: 24.5±7.6, P<0.0001 vs. PE2: 26.9±6.7, P<0.0001), and a positive correlation was observed between clot volume and change in mPAP (PE1: r=0.69, P=0.025; PE1 + PE2: r=0.60, P=0.063). Mean arterial pressure (MAP; mmHg) (baseline: 57.5±5.1 vs. PE1: 59.0±9.1, P=0.918 vs. PE2: 60.9±9.6, P=0.664) remained stable. No complications were observed., Conclusions: EBUS allows minimally invasive, precise, and reliable generation of pulmonary emboli in pigs. This model may serve as an important tool for new PE-related diagnostic and therapeutic research., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-21-1242/coif). KY reports that this work was supported by a research grant from Olympus Corporation, and KY is a consultant for Olympus. The other authors have no conflicts of interest to declare., (2022 Journal of Thoracic Disease. All rights reserved.)
- Published
- 2022
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38. HLA-B*15:11 status and carbamazepine-induced severe cutaneous adverse drug reactions in HLA-B*15:02 negative Chinese.
- Author
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Wong CSM, Yap DYH, Ip P, Wong WHS, Chua GT, Yeung CK, Chan HHL, and Kwok JSY
- Subjects
- Carbamazepine, China, Genetic Predisposition to Disease, HLA-B Antigens genetics, HLA-B15 Antigen genetics, Humans, Anticonvulsants, Stevens-Johnson Syndrome
- Abstract
Background: HLA-B*15:11 is associated with carbamazepine (CBZ)-induced severe cutaneous adverse drug reactions (SCARs) in Japanese and some Asian populations, but such data remains relatively limited in Chinese. Routine HLA-B*15:02 screening is mandatory before CBZ commencement, however, SCARs related to CBZ were still observed in non-HLA*B-15:02 carriers., Objective: We aimed to find out the prevalence of HLA-B*15:11 in Chinese patients and its associations with CBZ-induced SCARs., Method: We screened 8,328 blood samples collected for HLA allele typing before CBZ commencement during the period of January 2014 to December 2019. In HLA-B*15:02 negative Chinese patients, HLA-B*15:11 status were further screened, and the incidence of SCARs in the CBZ group was compared with the control group without CBZ use., Result: In this cohort, 1416 out of 8328 patients (17%) tested HLA-B*15:02 positive and were advised to avoid CBZ, while 80 (0.96%) were found to be HLA-B*15:11 positive. In 6911 (83%) patients who tested HLA-B*15:02 negative, 70 (1.01%) were HLA-B*15:11 positive. Five out of 70 (7.14%) patients had SCARs. The incidence of SCARs in HLA-B*15:11 carriers who received CBZ was significantly higher than those without CBZ (17.4% [4/23] vs. 2.13% [1/47], P = 0.037*). The odds ratio was 9.68 (95% CI 1.02-92.4, P = 0.048*). These included: one Stevens-Johnson syndrome (SJS), two DRESS, and one MPE after CBZ use, while one developed MPE after phenytoin use in control., Conclusion: HLA-B*15:11 is a potential risk factor of CBZ-induced SCARs in HLA-B*15:02 negative Chinese patients. Further screening of HLA-B*15:11 status in those HLA-B*15:02 negative patients is recommended to avoid undesirable SCARs., (© 2021 the International Society of Dermatology.)
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- 2022
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39. Neuroprotective effects of wolfberry in normal tension glaucoma: abridged secondary publication.
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Lai JSM, Chan HHL, Chan JCH, Lo ACY, Lee JWY, Chang RCC, and So KF
- Subjects
- Humans, Intraocular Pressure, Glaucoma, Low Tension Glaucoma, Lycium, Neuroprotective Agents pharmacology, Neuroprotective Agents therapeutic use
- Published
- 2022
40. Association of Plate Contouring With Hardware Complications Following Mandibular Reconstruction.
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Davies JC, Chan HHL, Yao CMKL, Ziai H, Dixon PR, Chepeha DB, Goldstein DP, de Almeida JR, Gilbert RW, and Irish JC
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Free Tissue Flaps surgery, Humans, Male, Mandibular Osteotomy methods, Mandibular Reconstruction adverse effects, Mandibular Reconstruction instrumentation, Middle Aged, Retrospective Studies, Young Adult, Bone Plates adverse effects, Mandibular Reconstruction methods
- Abstract
Objectives/hypothesis: Despite considerable effort being dedicated to contouring reconstruction plates, there remains limited evidence demonstrating an association between contour and reconstructive outcomes. We sought to evaluate whether optimizing mandibular reconstruction plate contouring is associated with reduced postoperative hardware complications., Study Design: Retrospective cohort study., Methods: A cohort study was performed with adult patients (age ≥18 years) who underwent mandibulectomy and osseous free flap reconstruction following oncologic ablation at the University Health Network in Toronto, Canada, between January 1, 2003 and December 31, 2014. Patients with computed tomography scans performed within 1 year of reconstruction were included. Computer-based three-dimensional models were generated and used to calculate the mean plate-to-bone gap (mm). The primary outcome was plate exposure. Secondary outcome included a composite of plate exposure or intraoral dehiscence. Logistic regression models were fitted for each outcome accounting for other patient and surgical characteristics associated with the primary outcome., Results: Ninety-four patients met inclusion criteria, with a mean age of 60.4 (standard deviation [SD] 14.9). The mean follow-up time was 31.4 months (range 3-94). Reconstruction was performed with fibular (57%) and scapular free flaps (43%). In the multivariable model, small mean plate-to-bone gap (<1 mm) was independently associated with 86% reduced odds of plate exposure (odds ratio [OR] 0.12; 95% confidence interval [CI] 0.02-0.55). Mean plate-to-bone gap less than 1 mm was also independently associated with reduced odds of developing a composite of plate exposure or intraoral dehiscence (OR, 0.29; 95%CI, 0.11-0.75)., Conclusion: Optimizing plate contouring during mandibular reconstruction may decrease the development of postoperative hardware complications., Level of Evidence: 4 Laryngoscope, 132:61-66, 2022., (© 2021 The American Laryngological, Rhinological and Otological Society, Inc.)
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- 2022
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41. Navigation-Guided Transnasal Endoscopic Delineation of the Posterior Margin for Maxillary Sinus Cancers: A Preclinical Study.
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Taboni S, Ferrari M, Daly MJ, Chan HHL, Eu D, Gualtieri T, Jethwa AR, Sahovaler A, Sewell A, Hasan W, Berania I, Qiu J, de Almeida J, Nicolai P, Gilbert RW, and Irish JC
- Abstract
Background: The resection of advanced maxillary sinus cancers can be challenging due to the anatomical proximity to surrounding critical anatomical structures. Transnasal endoscopy can effectively aid the delineation of the posterior margin of resection. Implementation with 3D-rendered surgical navigation with virtual endoscopy (3D-SNVE) may represent a step forward. This study aimed to demonstrate and quantify the benefits of this technology., Material and Method: Four maxillary tumor models with critical posterior extension were created in four artificial skulls (Sawbones
® ). Images were acquired with cone-beam computed tomography and the tumor and carotid were contoured. Eight head and neck surgeons were recruited for the simulations. Surgeons delineated the posterior margin of resection through a transnasal approach and avoided the carotid while establishing an adequate resection margin with respect to tumor extirpation. Three simulations were performed: 1) unguided: based on a pre-simulation study of cross-sectional imaging; 2) tumor-guided: guided by real-time tool tracking with 3D tumor and carotid rendering; 3) carotid-guided: tumor-guided with a 2-mm alert cloud surrounding the carotid. Distances of the planes from the carotid and tumor were classified as follows and the points of the plane were classified accordingly: "red": through the carotid artery; "orange": <2 mm from the carotid; "yellow": >2 mm from the carotid and within the tumor or <5 mm from the tumor; "green": >2 mm from the carotid and 5-10 mm from the tumor; and "blue": >2 mm from the carotid and >10 mm from the tumor. The three techniques (unguided, tumor-guided, and carotid-guided) were compared., Results: 3D-SNVE for the transnasal delineation of the posterior margin in maxillary tumor models significantly improved the rate of margin-negative clearance around the tumor and reduced damage to the carotid artery. "Green" cuts occurred in 52.4% in the unguided setting versus 62.1% and 64.9% in the tumor- and carotid-guided settings, respectively ( p < 0.0001). "Red" cuts occurred 6.7% of the time in the unguided setting versus 0.9% and 1.0% in the tumor- and carotid-guided settings, respectively ( p < 0.0001)., Conclusions: This preclinical study has demonstrated that 3D-SNVE provides a substantial improvement of the posterior margin delineation in terms of safety and oncological adequacy. Translation into the clinical setting, with a meticulous assessment of the oncological outcomes, will be the proposed next step., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Taboni, Ferrari, Daly, Chan, Eu, Gualtieri, Jethwa, Sahovaler, Sewell, Hasan, Berania, Qiu, de Almeida, Nicolai, Gilbert and Irish.)- Published
- 2021
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42. Augmented Reality and Intraoperative Navigation in Sinonasal Malignancies: A Preclinical Study.
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Sahovaler A, Chan HHL, Gualtieri T, Daly M, Ferrari M, Vannelli C, Eu D, Manojlovic-Kolarski M, Orzell S, Taboni S, de Almeida JR, Goldstein DP, Deganello A, Nicolai P, Gilbert RW, and Irish JC
- Abstract
Objective: To report the first use of a novel projected augmented reality (AR) system in open sinonasal tumor resections in preclinical models and to compare the AR approach with an advanced intraoperative navigation (IN) system., Methods: Four tumor models were created. Five head and neck surgeons participated in the study performing virtual osteotomies. Unguided, AR, IN, and AR + IN simulations were performed. Statistical comparisons between approaches were obtained. Intratumoral cut rate was the main outcome. The groups were also compared in terms of percentage of intratumoral, close, adequate, and excessive distances from the tumor. Information on a wearable gaze tracker headset and NASA Task Load Index questionnaire results were analyzed as well., Results: A total of 335 cuts were simulated. Intratumoral cuts were observed in 20.7%, 9.4%, 1.2,% and 0% of the unguided, AR, IN, and AR + IN simulations, respectively (p < 0.0001). The AR was superior than the unguided approach in univariate and multivariate models. The percentage of time looking at the screen during the procedures was 55.5% for the unguided approaches and 0%, 78.5%, and 61.8% in AR, IN, and AR + IN, respectively (p < 0.001). The combined approach significantly reduced the screen time compared with the IN procedure alone., Conclusion: We reported the use of a novel AR system for oncological resections in open sinonasal approaches, with improved margin delineation compared with unguided techniques. AR improved the gaze-toggling drawback of IN. Further refinements of the AR system are needed before translating our experience to clinical practice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sahovaler, Chan, Gualtieri, Daly, Ferrari, Vannelli, Eu, Manojlovic-Kolarski, Orzell, Taboni, de Almeida, Goldstein, Deganello, Nicolai, Gilbert and Irish.)
- Published
- 2021
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43. Pregnancy and the eye.
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Khong EWC, Chan HHL, Watson SL, and Lim LL
- Subjects
- Eye, Female, Humans, Pregnancy, Diabetic Retinopathy, Glaucoma surgery, Laser Therapy, Trabeculectomy
- Abstract
Purpose of Review: The aim of this study was to summarize common eye changes that may occur during pregnancy, and how pregnancy may affect preexisting eye conditions such as glaucoma and diabetic retinopathy. Challenges and complexities surrounding the treatment of these eye conditions during pregnancy are also highlighted., Recent Findings: Refractive changes are common and may persist in the postpartum in patients with keratoconus. Although new medical and surgical glaucoma treatments are available, their safety in pregnancy is unknown. Limited use of topical and systemic glaucoma therapies is recommended, with a preference for selective laser trabeculoplasty as first line treatment in appropriate cases. The impact of pregnancy on diabetic retinopathy remains unclear. Although anti-vascular endothelial growth factor agents are first-line treatment for sight-threatening diabetic retinopathy, their effect on the developing foetus remains unknown and are therefore best avoided in the first and second trimesters. Noninfectious uveitis tends to become less active during pregnancy, allowing the potential tapering of systemic therapy and the use of local topical or injected corticosteroid treatment for active disease as required., Summary: Significant changes can occur to the eye during pregnancy, wherein the optimal treatment for many ocular conditions remains uncertain, highlighting the need for further research to develop clear recommendations that best balance the need to preserve the mother's sight, and the health of the developing foetus. The need for preconception planning, and collaborative multidisciplinary care between the obstetrician, physician, ophthalmologist and paediatrician is paramount., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
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44. Cell-free DNA and circulating tumor cell kinetics in a pre-clinical head and neck Cancer model undergoing radiation therapy.
- Author
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Muhanna N, Eu D, Chan HHL, Douglas C, Townson JL, Di Grappa MA, Mohamadi RM, Kelley SO, Bratman SV, and Irish JC
- Subjects
- Animals, Biomarkers, Tumor blood, Carcinoma, Squamous Cell chemically induced, Circulating Tumor DNA blood, Cottontail rabbit papillomavirus, Epithelial Cell Adhesion Molecule blood, Head and Neck Neoplasms blood, Head and Neck Neoplasms chemically induced, Head and Neck Neoplasms radiotherapy, Immunomagnetic Separation methods, Liquid Biopsy methods, Male, Mouth Neoplasms chemically induced, Mouth Neoplasms virology, Nanoparticles, Neoplasm Transplantation, Open Reading Frames, Rabbits, Radiotherapy Dosage, Tumor Burden, Carcinoma, Squamous Cell blood, Carcinoma, Squamous Cell radiotherapy, Cell-Free Nucleic Acids blood, Mouth Neoplasms blood, Mouth Neoplasms radiotherapy
- Abstract
Background: Monitoring circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs), known as liquid biopsies, continue to be developed as diagnostic and prognostic markers for a wide variety of cancer indications, mainly due to their minimally invasive nature and ability to offer a wide range of phenotypic and genetic information. While liquid biopsies maintain significant promising benefits, there is still limited information regarding the kinetics of ctDNA and CTCs following radiation therapy which remains a vital treatment modality in head and neck cancers. This study aims to describe the kinetics of ctDNA and CTCs following radiation exposure in a preclinical rabbit model with VX2 induced buccal carcinoma., Methods: Seven rabbits were inoculated with VX2 cells in the buccal mucosa and subjected to radiation. At selected time points, blood sampling was performed to monitor differing levels of ctDNA and CTC. Plasma ctDNA was measured with quantitative PCR for papillomavirus E6 while CTCs were quantified using an immunomagnetic nanoparticles within a microfluidic device. Comparisons of CTC detection with EpCAM compared to multiple surface markers (EGFR, HER2 and PSMA) was evaluated and correlated with the tumor size., Results: Plasma ctDNA reflects the overall tumor burden within the animal model. Analysis of correlations between ctDNA with tumor and lymph node volumes showed a positive correlation (R = 0.452 and R = 0.433 [p < 0.05]), respectively. Over the course of treatment, ctDNA levels declined and quickly becomes undetectable following tumor eradication. While during the course of treatment, ctDNA levels were noted to rise particularly upon initiation of radiation following scheduled treatment breaks. Levels of CTCs were observed to increase 1 week following inoculation of tumor to the primary site. For CTC detection, the use of multiple surface markers showed a greater sensitivity when compared to detection using only EpCAM. Plasma CTC levels remained elevated following radiation therapy which may account for an increased shedding of CTCs following radiation., Conclusion: This study demonstrates the utility of ctDNA and CTCs detection in response to radiation treatment in a preclinical head and neck model, allowing for better understanding of liquid biopsy applications in both clinical practice and research development., (© 2021. The Author(s).)
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- 2021
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45. Fractional 1064 nm Picosecond Laser in Treatment of Melasma and Skin Rejuvenation in Asians, A Prospective Study.
- Author
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Wong CSM, Chan MWM, Shek SYN, Yeung CK, and Chan HHL
- Subjects
- Adult, Asian People, Humans, Middle Aged, Prospective Studies, Rejuvenation, Treatment Outcome, Hyperpigmentation, Lasers, Solid-State therapeutic use, Melanosis therapy, Skin Aging
- Abstract
Background and Objectives: Facial melasma is a disfiguring pigmentation and occurs frequently with aging skin. Topical treatment alone was often suboptimal. A recent study showed that fractional picosecond laser has promising result in benign pigmentary lesions. This study aims to investigate the efficacy and safety of 1064 nm picosecond laser in treatment of facial melasma and skin rejuvenation in Asian skin., Study Design/materials and Methods: Patients of Asian descent seeking treatment for facial melasma and skin rejuvenation were screened and recruited. Each patient received up to nine laser treatments at 4-6 weeks intervals with a fractionated nonablative 1064 nm picosecond laser. Baseline and posttreatment modified Melasma Area Severity Index (mMASI) and Global Aesthetic Improvement Scale (IGAS) were assessed by blinded investigators based on the clinical photographs. Subject overall satisfaction was assessed by the questionnaires after treatment. All adverse events were documented., Results: Twenty patients were recruited with a median age of 52.7 ± 8.2 years. Three subjects had Fitzpatrick skin type III and 17 had skin type IV. All subjects received nine laser sessions. Over 70% of patients were satisfied with the treatment outcomes. There was a statistically significant improvement in mMASI which reduced from 10.8 at baseline to 2.7 and 3.6 at 6 and 12 weeks post-treatment, respectively (both P < 0.01). For skin rejuvenation, 70% reported at least a moderate improvement at 6 weeks of post-treatment. No major side-effect was reported. Erythema was the most frequent transient response, while some reported edema (1.1%). Both resolved spontaneously. None reported hypo- or hyperpigmentation after treatment. The overall mean pain scare (VAS) was 1.92., Conclusion: Fractionated non-ablative 1064 nm picosecond laser was effective in treatment of melasma and skin rejuvenation. It was also safe and well tolerated. Importantly, there was no hypo or hyperpigmentation reported. Lasers Surg. Med. 00:00-00, 2021. © 2021 Wiley Periodicals LLC., (© 2021 Wiley Periodicals LLC.)
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- 2021
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46. Rabbit VX2 head and neck squamous cell models for translational head and neck theranostic technology development.
- Author
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Muhanna N, Douglas CM, Chan HHL, Daly MJ, Townson JL, Ferrari M, Eu D, Akens M, Chen J, Zheng G, and Irish JC
- Subjects
- Animals, Disease Models, Animal, Rabbits, Carcinoma, Squamous Cell diagnostic imaging, Carcinoma, Squamous Cell therapy, Diagnostic Imaging methods, Head and Neck Neoplasms diagnostic imaging, Phototherapy methods, Precision Medicine methods
- Published
- 2021
- Full Text
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47. Integrating Clinical Data and Tear Proteomics to Assess Efficacy, Ocular Surface Status, and Biomarker Response After Orthokeratology Lens Wear.
- Author
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Tse JSH, Cheung JKW, Wong GTK, Lam TC, Choi KY, So KHY, Lam CDM, Sze AYH, Wong ACK, Yee GMC, and Chan HHL
- Subjects
- Adult, Biomarkers, Corneal Topography, Humans, Refraction, Ocular, Young Adult, Myopia therapy, Proteomics
- Abstract
Purpose: This study evaluated the efficacy and ocular surface status of Breath-O Correct, novel orthokeratology (OK) lenses, worn overnight for 3 months. Lens-induced changes in the tear proteome were evaluated., Methods: Thirty-one subjects, aged 19 to 26 years with refractive error from -1.00 to -5.00 D, were randomly assigned 1:1 to the treatment or control group. Refraction, visual acuity, corneal integrity, biomechanics and endothelial health, ocular surface changes, and subjective symptoms were assessed at the baseline, one-month, and three-month visits. The tear proteome was characterized over time using sequential window acquisition of all theoretical ion spectra mass spectrometry., Results: Lenses improved uncorrected visual acuity and reduced spherical powers with similar efficacy to other OK lenses. Significant reductions (P < 0.05) in corneal hysteresis (11.12 ± 1.12 to 10.38 ± 1.36 mm Hg) and corneal resistance factor (11.06 ± 1.32 to 9.90 ± 1.45 mm Hg) were observed in the treatment group after one month of lens wear, whereas other assessed factors remained unchanged. Thirteen and eight differentially expressed proteins were found after one month and three months of lens wear, respectively. Two proteins (proline-rich protein 27 and immunoglobulin V regions) were differentially expressed at both visits., Conclusions: Over a three-month period, Breath-O Correct lenses were overall safe, well tolerated, efficacious in refractive power reduction, and comparable with other OK lenses. Furthermore, their use caused only minor noninflammatory protein expression changes in the tear proteome., Translational Relevance: This study investigated the safety of orthokeratology contact lenses on the ocular surface in molecular aspects and standard clinical parameters.
- Published
- 2021
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48. Determination of Optical Properties and Photodynamic Threshold of Lung Tissue for Treatment Planning of In Vivo Lung Perfusion Assisted Photodynamic Therapy.
- Author
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Ramadan KT, McFadden C, Gomes B, Schwiegelshohn F, Ribeiro RVP, Chan HHL, Betz V, Cypel M, and Lilge L
- Subjects
- Animals, Humans, Lung diagnostic imaging, Perfusion, Photosensitizing Agents pharmacology, Swine, Photochemotherapy methods, Porphyrins
- Abstract
Background: Isolated lung metastases in sarcoma and colorectal cancer patients are inadequately treated with current standard therapies. In Vivo Lung Perfusion, a novel platform, could overcome limitations to photodynamic therapy treatment volumes by using low cellular perfusate, removing blood, theoretically allowing greater light penetration. To develop personalized photodynamic therapy protocols requires in silico light propagation simulations based on optical properties and maximal permissible photodynamic threshold dose of lung tissue. This study presents quantification of optical properties for two perfusates and the photodynamic threshold for 5-ALA and Chlorin e6., Methods: Porcine and human lungs were placed on Ex Vivo Lung Perfusion, and perfused with acellular solution or blood. Isotropic diffusers were placed within bronchi and on lung surface for light transmission measurements, from which absorption and light scattering properties were calculated at multiple wavelengths. Separately, pigs were injected with 5-ALA or Chlorin e6, and lung tissue was irradiated at increasing doses. Resultant lesion sizes were measured by CT and histology to quantify the photodynamic threshold., Results: Low cellular perfusate reduced the tissue absorption coefficient significantly, increasing penetration depth of light by 3.3 mm and treatment volumes 3-fold. The photodynamic threshold for lung exposed to 5-ALA was consistent with other malignancies. Chlorin e6 levels were undetectable in lung tissue and did not demonstrate photodynamic-induced necrosis., Conclusions: Light penetration with low cellular perfusate is significantly greater and could enable treatments for diffuse disease. This data aids photodynamic treatment planning and will guide clinical translation of photodynamic therapy protocols in the lung, especially during lung perfusion., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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49. Utilizing Advanced Technology to Facilitate Diagnosis of Rare Retinal Disorders: A Case of Bietti Crystalline Dystrophy.
- Author
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Choi KY, Wong HHY, and Chan HHL
- Subjects
- Adult, Corneal Dystrophies, Hereditary, Female, Fluorescein Angiography, Humans, Retinal Diseases, Technology, Visual Acuity, Retinal Degeneration, Tomography, Optical Coherence
- Abstract
Significance: Optometrists, as primary eye care providers, encounter patients with rare ocular disease such as Bietti crystalline dystrophy from time to time. Using advanced technologies, which are also useful in managing common ocular conditions, to facilitate a prompt diagnosis is highly recommended., Purpose: This report describes a patient with clinically diagnosed Bietti crystalline dystrophy with findings on funduscopy, multimodal imaging, and visual electrophysiology., Case Report: A 41-year-old Chinese woman who had subjectively progressing dimmed vision (especially in the left eye) for 9 months was referred to our clinic to test for retinitis pigmentosa. Best-corrected visual acuities were 6/6 and 6/7.6 in the right and left eyes, respectively. Funduscopy revealed multiple crystalline deposits on the posterior pole in both eyes. The 30-2 perimetry displayed bi-inferotemporal scotoma (left > right eye). Scotopic flash electroretinogram (ERG) yielded a normal result, whereas photopic ERG was slightly attenuated. Electro-oculogram showed an abnormal adaptation time course of the retinal pigmented epithelium (RPE). Multifocal ERG revealed a decreased central retinal response, but paracentral responses were relatively better preserved. Optical coherence tomography showed multiple patches of RPE atrophy, with disruption of the left ellipsoid zone. Outer retinal tubulations, hyperreflective dots on RPE-Bruch's membrane interface, and intraretinal bright spots were also identified., Conclusions: Rare ocular diseases like Bietti crystalline dystrophy can be encountered by optometrists. This case report shows the ophthalmic findings of a rare chorioretinal dystrophy and provides insight on how to better use advanced equipment in an optometric practice to facilitate prompt diagnoses., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2021 American Academy of Optometry.)
- Published
- 2021
- Full Text
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50. Evaluating an Image-Guided Operating Room with Cone Beam CT for Skull Base Surgery.
- Author
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Muhanna N, Douglas CM, Daly MJ, Chan HHL, Weersink R, Townson J, Monteiro E, Yu E, Weimer E, Kucharczyk W, Jaffray DA, Irish JC, and de Almeida JR
- Abstract
Importance Skull base surgery requires precise preoperative assessment and intraoperative management of the patient. Surgical navigation is routinely used for complex skull base cases; however, the image guidance is commonly based on preoperative scans alone. Objective The primary objective of this study was to assess the image quality of intraoperative cone-beam computed tomography (CBCT) within anatomical landmarks used in sinus and skull base surgery. The secondary objective was to assess the registration error of a surgical navigation system based on intraoperative CBCT. Design Present study is a retrospective case series of image quality after intraoperative cone beam CT. Setting The study was conducted at Toronto General Hospital and Princess Margaret Cancer Centre, University Health Network, Toronto. Participants A total of 46 intraoperative scans (34 patients, 21 skull base, 13 head and neck) were studied. Main Outcome and Measures Thirty anatomical landmarks (vascular, soft tissue, and bony) within the sinuses and anterior skull base were evaluated for general image quality characteristics: (1) bony detail visualization; (2) soft-tissue visualization; (3) vascular visualization; and (4) freedom from artifacts (e.g., metal). Levels of intravenous (IV) contrast enhancement were quantified in Hounsfield's units (HU). Standard paired-point registration between imaging and tracker coordinates was performed using 6 to 8 skin fiducial markers and the corresponding fiducial registration error (FRE) was measured. Results Median score for bony detail on CBCT was 5, remaining at 5 after administration of IV contrast. Median soft-tissue score was 2 for both pre- and postcontrast. Median vascular score was 1 precontrast and 3 postcontrast. Median score for artifacts on CBCT were 2 for both pre-and postcontrast, and metal objects were noted to be the most significant source of artifact. Intraoperative CBCT allowed preresection images and immediate postresection images to be available to the skull base surgeon. There was a significant improvement in mean (standard deviation [SD]) CT intensity in the left carotid artery postcontrast 334 HU (67 HU) ( p < 10
-10 ). The mean FRE was 1.8 mm (0.45 mm). Conclusion Intraoperative CBCT in complex skull base procedures provides high-resolution bony detail allowing immediate assessment of complex resections. The use of IV contrast with CBCT improves the visualization of vasculature. Image-guidance based on CBCT yields registration errors consistent with standard techniques., Competing Interests: Conflict of Interest None declared., (Thieme. All rights reserved.)- Published
- 2021
- Full Text
- View/download PDF
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