Publications by authors named "Carmen K M Chan"

45 Publications

A Multitask Deep-Learning System to Classify Diabetic Macular Edema for Different Optical Coherence Tomography Devices: A Multicenter Analysis.

Diabetes Care 2021 Sep 27;44(9):2078-2088. Epub 2021 Jul 27.

Byers Eye Institute at Stanford, Stanford University School of Medicine, Palo Alto, CA.

Objective: Diabetic macular edema (DME) is the primary cause of vision loss among individuals with diabetes mellitus (DM). We developed, validated, and tested a deep learning (DL) system for classifying DME using images from three common commercially available optical coherence tomography (OCT) devices.

Research Design And Methods: We trained and validated two versions of a multitask convolution neural network (CNN) to classify DME (center-involved DME [CI-DME], non-CI-DME, or absence of DME) using three-dimensional (3D) volume scans and 2D B-scans, respectively. For both 3D and 2D CNNs, we used the residual network (ResNet) as the backbone. For the 3D CNN, we used a 3D version of ResNet-34 with the last fully connected layer removed as the feature extraction module. A total of 73,746 OCT images were used for training and primary validation. External testing was performed using 26,981 images across seven independent data sets from Singapore, Hong Kong, the U.S., China, and Australia.

Results: In classifying the presence or absence of DME, the DL system achieved area under the receiver operating characteristic curves (AUROCs) of 0.937 (95% CI 0.920-0.954), 0.958 (0.930-0.977), and 0.965 (0.948-0.977) for the primary data set obtained from CIRRUS, SPECTRALIS, and Triton OCTs, respectively, in addition to AUROCs >0.906 for the external data sets. For further classification of the CI-DME and non-CI-DME subgroups, the AUROCs were 0.968 (0.940-0.995), 0.951 (0.898-0.982), and 0.975 (0.947-0.991) for the primary data set and >0.894 for the external data sets.

Conclusions: We demonstrated excellent performance with a DL system for the automated classification of DME, highlighting its potential as a promising second-line screening tool for patients with DM, which may potentially create a more effective triaging mechanism to eye clinics.
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http://dx.doi.org/10.2337/dc20-3064DOI Listing
September 2021

Comparison of Peripapillary Vessel Density of Acute Nonarteritic Anterior Ischemic Optic Neuropathy and Other Optic Neuropathies With Disc Swelling Using Optical Coherence Tomography Angiography: A Pilot Study.

J Neuroophthalmol 2020 Oct 26. Epub 2020 Oct 26.

Hong Kong Eye Hospital (JCC, JKHL, CKMC), Hong Kong, China; Department of Ophthalmology and Visual Sciences (JCC, NCYC, CYC, JKHL, CKMC), the Chinese University of Hong Kong, Hong Kong, China; and Department of Ophthalmology and Visual Sciences (NCYC), the Prince of Wales Hospital and Alice Ho Miu Ling Nethersole Hospital, Hong Kong, China.

Background: The purpose of this study is to quantitatively compare the peripapillary vessel density (PPVD), measured with optical coherence tomography angiography (OCT-A), between acute nonarteritic anterior ischemic optic neuropathy (NAION) and other causes of disc swelling ("others").

Methods: In this prospective comparative case series, patients with unilateral disc swelling due to acute NAION (n = 7) and "others" (n = 7) underwent OCT-A scanning of the optic nerve head with a swept-source OCT (Triton DRI-OCT), in addition to functional assessment. OCT-A images were analyzed using an automated customized MATLAB program. Comparison was made between total and 6 sectoral PPVD (radial peripapillary capillary [RPC] and choroid layers) of affected and fellow eyes; and between the 2 groups' affected eyes. Five NAION patients had repeated assessments at 1, 3, and 6 months.

Results: Acute NAION eyes had a significantly lower total and superonasal PPVD (both layers) compared to fellow eyes. No such difference was observed in "others" group for the RPC layer. NAION eyes also had significantly lower total RPC PPVD than affected eyes in the "others" group. Over 6 months, NAION eyes had persistently lower RPC PPVD compared to fellow eyes but the reduced choroidal PPVD resolved by 1 month.

Conclusion: The study demonstrated reduced superonasal and total RPC PPVD in acute NAION, which persisted over 6 months. Because there is currently no single diagnostic test for NAION, use of OCT-A images to analyze RPC PPVD may potentially help distinguish acute NAION from other causes of disc swelling by quantitatively demonstrating capillary dropout in the RPC layer.
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http://dx.doi.org/10.1097/WNO.0000000000001106DOI Listing
October 2020

Efficacy and safety of oral valganciclovir in cytomegalovirus anterior uveitis with uncontrolled intraocular pressure.

Br J Ophthalmol 2020 Oct 3. Epub 2020 Oct 3.

Hong Kong Eye Hospital, Hong Kong SAR, China.

Background/aims: While cytomegalovirus (CMV) anterior uveitis (AU) patients often require glaucoma surgery, the effectiveness of systemic anti-viral in long-term intraocular pressure (IOP) control is not well established. Our study aims to identify the 2-year efficacy and safety of oral valganciclovir in CMV AU with uncontrolled IOP.

Methods: In this retrospective case series, one eye from each of 17 immunocompetent PCR-proven patients with CMV AU who received a single course of oral valganciclovir for 20-148 days for medically uncontrolled IOP during 2008-2018 were identified. They were examined at baseline, week 2, months 1, 2 and 3, then every 3 months up to 2 years after commencement of valganciclovir, or until IOP-lowering procedure.

Results: Median baseline IOP and IOP-lowering medication were 27.0 mm Hg (IQR: 22.9-31.0 mm Hg), and 4.0, respectively. IOP was significantly lower than baseline from 2 weeks to 12 months and at 21 and 24 months after starting valganciclovir (p=0.001 to 0.041, Wilcoxon sign-rank test), with 16.9-46.0% median IOP reduction. Seven (41.2%) and six (35.3%) patients had IOP≤21 mm Hg with same, or reduced, topical medications by 12 and 24 months, respectively. Median time to IOP-lowering intervention or second course of valganciclovir was 12.4 months. There was no serious medication-related adverse event. Common side effects included reduced monocyte count (9 patients) and deranged renal function/electrolytes (5 patients). IOP spike and wound leak occurred in 35.5% and 29.4% of patients, respectively, after diagnostic aqueous tap.

Conclusion: In CMV AU with uncontrolled IOP, >1/3 of the patients avoided glaucoma surgery over 2 years with a course of oral valganciclovir.
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http://dx.doi.org/10.1136/bjophthalmol-2020-317044DOI Listing
October 2020

Ophthalmology in the time of COVID-19: experience from Hong Kong Eye Hospital.

Int J Ophthalmol 2020 18;13(6):851-859. Epub 2020 Jun 18.

Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong SAR, China.

Aim: To review international guidelines and to share our infection control experience during the coronavirus disease 2019 (COVID-19) pandemic at a tertiary eye centre in Hong Kong.

Methods: Infection control guidelines and recommendations from international ophthalmological bodies are reviewed and discussed. The measures at our hospital were drawn up as per international and local health authorities' guidelines and implemented with the collaboration of doctors, nurses and administrative staff.

Results: The aims of our infection control measures are to 1) minimize cross-infection within the hospital; 2) protect and support hospital staff; 3) ensure environmental control. To minimize the risk of cross-infection, outpatient attendance and elective surgery have been reduced by 40%, and general anesthesia procedures were reduced by 90%. Patients entering the hospital are screened for fever, travel history, contact and cluster history, and COVID-19 related symptoms. To protect and support hospital staff, we ensure provision of adequate personal protective equipment (PPE) and provide clear guidelines on the level of PPE needed, depending on the clinical situation. Other protective measures include provision of work uniforms, easy access to alcohol-based hand rub, opening new lunch areas, implementation of self-monitoring and self-reporting systems, and communication online education and updates. Finally, environmental control is achieved by ensuring regular disinfection of the hospital premise, enhancing ventilation, and usage of disposable ophthalmic instruments.

Conclusion: Our multi-pronged approach to infection control is, so far, successful in minimizing infection risks, while allowing the maintenance of essential ophthalmic services.
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http://dx.doi.org/10.18240/ijo.2020.06.01DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7270264PMC
June 2020

Atypical presentations of intracranial dysgerminoma mimicking central nervous system inflammatory or demyelinating disease.

Can J Ophthalmol 2020 04 13;55(2):159-166. Epub 2019 Sep 13.

Department of Pathology, Houston Methodist Hospital, Houston, TX.

Objectives: The aim of this study is to report a case series of atypical presentations of intracranial dysgerminoma in which the diagnosis was delayed due to clinical and radiographic findings initially suggestive of CNS inflammatory or demyelinating diseases, such as MS.

Methods: This study is a case series detailing the history, clinical presentations, radiographic and laboratory results, and management of three patients with biopsy-proven intracranial dysgerminoma.

Results: All three patients demonstrated hyperintense lesions on MRI that were more suggestive of demyelinating or inflammatory diseases, including lesions involving the midbrain and corpus callosum. All three patients were serum positive for oligoclonal bands and negative for both AFP and beta-hCG (these two markers are commonly seen in dysgerminoma cases). One case involved a steroid-responsive tumor whereas the other two cases either did not respond to steroids or steroids were withheld due to uncertainty of etiology. Following biopsy, all three results were consistent with dysgerminoma.

Conclusion: Clinicians should be aware that dysgerminoma may mimic the clinical and radiographic presentations of demyelinating diseases such as MS. These lesions can cause acute visual loss or diplopia, have MRI and CSF findings that might mimic MS, and have been shown to respond to steroids. Atypical clinical (e.g., headache, dorsal midbrain syndrome, bilateral optic neuropathy) or atypical radiographic features (e.g., mass effect, hydrocephalus) should prompt consideration for repeat imaging and possible biopsy even if serum or CSF tumor markers (beta-hCG and AFP) are negative for dysgerminoma.
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http://dx.doi.org/10.1016/j.jcjo.2019.07.018DOI Listing
April 2020

OCT Angiography Metrics Predict Progression of Diabetic Retinopathy and Development of Diabetic Macular Edema: A Prospective Study.

Ophthalmology 2019 12 26;126(12):1675-1684. Epub 2019 Jun 26.

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. Electronic address:

Purpose: To prospectively determine the relationship of OCT angiography (OCTA) metrics to diabetic retinopathy (DR) progression and development of diabetic macular edema (DME).

Design: Prospective, observational study.

Participants: A total of 205 eyes from 129 patients with diabetes mellitus followed up for at least 2 years.

Methods: All participants underwent OCTA with a swept-source OCT device (DRI-OCT Triton, Topcon, Inc, Tokyo, Japan). Individual OCTA images of superficial capillary plexus (SCP) and deep capillary plexus (DCP) were generated by IMAGEnet6 (Basic License 10). After a quality check, automated measurements of foveal avascular zone (FAZ) area, FAZ circularity, vessel density (VD), and fractal dimension (FD) of both SCP and DCP were then obtained.

Main Outcome Measures: Progression of DR and development of DME.

Results: Over a median follow-up of 27.14 months (interquartile range, 24.16-30.41 months), 28 of the 205 eyes (13.66%) developed DR progression. Of the 194 eyes without DME at baseline, 17 (8.76%) developed DME. Larger FAZ area (hazard ratio [HR], 1.829 per SD increase; 95% confidence interval [CI], 1.332-2.512), lower VD (HR, 1.908 per SD decrease; 95% CI, 1.303-2.793), and lower FD (HR, 4.464 per SD decrease; 95% CI, 1.337-14.903) of DCP were significantly associated with DR progression after adjusting for established risk factors (DR severity, glycated hemoglobin, duration of diabetes, age, and mean arterial blood pressure at baseline). Lower VD of SCP (HR, 1.789 per SD decrease; 95% CI, 1.027-4.512) was associated with DME development. Compared with the model with established risk factors alone, the addition of OCTA metrics improved the predictive discrimination of DR progression (FAZ area of DCP, C-statistics 0.723 vs. 0.677, P < 0.001; VD of DCP, C-statistics 0.727 vs. 0.677, P = 0.001; FD of DCP, C-statistics 0.738 vs. 0.677, P < 0.001) and DME development (VD of SCP, C-statistics 0.904 vs. 0.875, P = 0.036).

Conclusions: The FAZ area, VD, and FD of DCP predict DR progression, whereas VD of SCP predicts DME development. Our findings provide evidence to support that OCTA metrics improve the evaluation of risk of DR progression and DME development beyond traditional risk factors.
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http://dx.doi.org/10.1016/j.ophtha.2019.06.016DOI Listing
December 2019

Proceedings of the Neuro-Ophthalmology Program of the 33rd Asia-Pacific Academy of Ophthalmology Congress, Hong Kong, 8-11 February 2018.

Neuroophthalmology 2018 Oct 23;42(5):326-333. Epub 2018 May 23.

Department of Ophthalmology, Hong Kong Eye Hospital, Kowloon, Hong Kong.

The 33rd Asia-Pacific Academy of Ophthalmology (APAO) Congress was held on Feb 8-11, 2018 in Hong Kong. This report summarized the highlights of the neuro-ophthalmology program of the Congress, including the scientific symposia (invited and submitted) and the social activities.
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http://dx.doi.org/10.1080/01658107.2018.1463386DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6152500PMC
October 2018

The Role of Optical Coherence Tomography in the Acute Management of Neuro-Ophthalmic Diseases.

Asia Pac J Ophthalmol (Phila) 2018 Jul-Aug;7(4):265-270. Epub 2018 Jun 25.

Hong Kong Eye Hospital, Hong Kong.

Optical coherence tomography (OCT) can provide high-speed and high-resolution images of the anatomical structures of the optic nerve head and macula. However, in neuro-ophthalmic conditions that present acutely, structural changes lag functional deficits, and the role of OCT in the acute setting has been challenged. This review aims to summarize the recent literature and evidence supporting the use of OCT in the acute management of some common neuro-ophthalmic scenarios, including the differential diagnosis of optic disc swelling, and in patients with suspected papilledema, optic neuritis, ischemic optic neuropathies, and Leber hereditary optic neuropathy. The limitations of OCT are also discussed.
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http://dx.doi.org/10.22608/APO.2018181DOI Listing
August 2018

The use of optical coherence tomography in neuro-ophthalmology.

Curr Opin Ophthalmol 2017 Nov;28(6):552-557

aHong Kong Eye Hospital bDepartment of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong.

Purpose Of Review: In the last decade, with the advances of optical coherence tomography (OCT) technology, different imaging protocols and analysis algorithms have been introduced to maximize the potential of this diagnostic tool in the evaluation of different eye diseases. This review aims to provide an update on these additional features, with respect to the management of a diverse range of neuro-ophthalmologic conditions.

Recent Findings: Macular ganglion cell complex (mGCC) analysis has been shown to be superior to peripapillary retinal nerve fiber layer (pRNFL) analysis in certain settings, such as differentiating Leber's hereditary optic neuropathy from functional visual loss; monitoring neurodegenerative diseases or multiple sclerosis; and predicting visual loss in nonarteritic ischemic optic neuropathy. mGCC analysis also demonstrates high correlation with perimetry and might serve as an early structural indicator of irreversible neuronal loss. Compared to pRNFL, retinal thickness analysis of the optic nerve head demonstrates better correlation with the severity of papilledema, thus enabling its possible application in detecting raised intracranial pressure, especially in the pediatric group. Upcoming research on emerging OCT technologies including OCT-angiography, enhanced depth imaging, retinal single-layer analysis and portable systems will hopefully further enhance the utility of OCT in the field.

Summary: It is crucial for neuro-ophthalmologists to be updated and familiar with these newer OCT imaging protocols and to make appropriate choices for different clinical scenarios, in order to optimize the diagnostic sensitivity and specificity.
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http://dx.doi.org/10.1097/ICU.0000000000000418DOI Listing
November 2017

Optic Disc and Macular Imaging in Blind Eyes from Non-glaucomatous Optic Neuropathy: A Study with Spectral-domain Optical Coherence Tomography.

Neuroophthalmology 2017 Feb 31;41(1):1-6. Epub 2016 Oct 31.

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Hong Kong Eye Hospital, Kowloon, Hong Kong.

The purpose of this study was to determine and compare the optic disc and macular thickness measurements using two spectral-domain optical coherence tomography (SD-OCT) instruments in long-standing blind eyes diagnosed with non-glaucomatous optic neuropathies (NGON). A prospective observational case-series design was used. Twelve eyes from 12 NGON patients with no light perception for at least 6 months underwent optic disc and macular imaging with Cirrus HD-OCT and Spectralis OCT. The correlation between the peripapillary retinal nerve fibre layer (PRNFL) and macular ganglion cell layer and inner plexiform layer (GCL+IPL) thicknesses, and between the duration of no light perception (NLP) and PRNFL/GCL+IPL thicknesses were determined using Spearman's correlation analysis. The mean average PRNFL thickness was 55.9 ± 4.8 µm for Cirrus HD-OCT, which was significantly thicker than that measured by Spectralis OCT (31.9 ± 7.4 µm; < 0.001). The mean central macular thickness on Cirrus HD-OCT was normal, but there was global thinning at the other macular areas. The mean average GCL+IPL thickness on Cirrus HD-OCT was 51.8 ± 5.8 µm. There was a good correlation between average PRNFL thickness and GCL+IPL thickness ( = 0.830, = 0.002); however, there was no significant correlation between the duration of NLP to the average PRNFL thickness (on either instruments) or GCL+IPL thickness on Cirrus HD-OCT ( > 0.7). These results show that there was residual PRNFL thickness in NGON eyes with NLP, which varied significantly between SD-OCT instruments. The values of the residual PRNFL and GCL+IPL thicknesses in blind eyes (the "floor" effect) may be useful for prognostic purposes for patients with partial optic atrophy.
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http://dx.doi.org/10.1080/01658107.2016.1238487DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5278782PMC
February 2017

Presumed Sterile Endophthalmitis Afer Intravitreal Triamcinolone (Kenalog)-More Common and Less Benign Than We Thought?

Asia Pac J Ophthalmol (Phila) 2017 Jan-Feb;6(1):45-49

Hong Kong Eye Hospital, Kowloon, Hong Kong.

Purpose: This study aimed to review the incidence and clinical outcome of presumed sterile endophthalmitis after the off-label use of intravitreal Kenalog injections (triamcinolone acetonide with 1.5% benzyl alcohol) and to compare it with the presumed sterile endophthalmitis incidence after intravitreal Kenacort-A (0.99% benzyl alcohol) at our center.

Design: This was a single-center, retrospective, consecutive, interventional case series of all patients who underwent intravitreal Kenalog injections at Hong Kong Eye Hospital from November 1, 2009, to July 31, 2012.

Methods: This was a retrospective medical records review.

Results: A total of 81 intravitreal Kenalog injections were performed. Ten eyes (12.3%) developed presumed sterile endophthalmitis, presenting clinically with dense anterior chamber cells, fibrin, hypopyon, and vitritis. All cases were treated with topical steroids and antibiotics. Although the inflammation resolved eventually in all cases, 2 eyes developed complications, resulting in eventual loss of best corrected visual acuity: one developed rhegmatogenous retinal detachment with choroidal detachment, and another developed vitreous hemorrhage.

Conclusions: The rate of presumed sterile endophthalmitis after Kenalog injection is much higher than our previous experience with Kenacort-A. To the best of our knowledge, this is the first study reporting the incidence of presumed sterile endophthalmitis using intravitreal Kenalog and Kenacort in the same center using the same injection technique. We believe that it may be due to a difference in the concentration of the preservative. Although sterile endophthalmitis is generally thought to run a benign course, this study has shown that serious complications may occur.
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http://dx.doi.org/10.1097/APO.0000000000000194DOI Listing
March 2017

Highly Phosphorescent Crystals of Square-Planar Platinum Complexes with Chiral Organometallic Linkers: Homochiral versus Heterochiral Arrangements, Induced Circular Dichroism, and TD-DFT Calculations.

Chemistry 2016 06 3;22(24):8032-7. Epub 2016 May 3.

UPMC Paris 06, Institut Parisien de Chimie Moléculaire (IPCM) UMR CNRS 8232, 4 place Jussieu, 75252, Paris cedex 05, France.

A novel class of chiral luminescent square-planar platinum complexes with a π-bonded chiral thioquinonoid ligand is described. Remarkably the presence of this chiral organometallic ligand controls the aggregation of this square planar luminophor and imposes a homo- or hetero-chiral arrangement at the supramolecular level, displaying non-covalent Pt-Pt and π-π interactions. Interestingly these complexes are highly luminescent in the crystalline state and their photophysical properties can be traced to their aggregation in the solid state. A TD-DFT calculation is obtained to rationalize this unique behavior.
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http://dx.doi.org/10.1002/chem.201601161DOI Listing
June 2016

Anti-Inflammatory Activities of Pentaherbs Formula, Berberine, Gallic Acid and Chlorogenic Acid in Atopic Dermatitis-Like Skin Inflammation.

Molecules 2016 Apr 20;21(4):519. Epub 2016 Apr 20.

Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China.

Atopic dermatitis (AD) is a common allergic skin disease, characterized by dryness, itchiness, thickening and inflammation of the skin. Infiltration of eosinophils into the dermal layer and presence of edema are typical characteristics in the skin biopsy of AD patients. Previous in vitro and clinical studies showed that the Pentaherbs formula (PHF) consisting of five traditional Chinese herbal medicines, Flos Lonicerae, Herba Menthae, Cortex Phellodendri, Cortex Moutan and Rhizoma Atractylodis at w/w ratio of 2:1:2:2:2 exhibited therapeutic potential in treating AD. In this study, an in vivo murine model with oxazolone (OXA)-mediated dermatitis was used to elucidate the efficacy of PHF. Active ingredients of PHF water extract were also identified and quantified, and their in vitro anti-inflammatory activities on pruritogenic cytokine IL-31- and alarmin IL-33-activated human eosinophils and dermal fibroblasts were evaluated. Ear swelling, epidermis thickening and eosinophils infiltration in epidermal and dermal layers, and the release of serum IL-12 of the murine OXA-mediated dermatitis were significantly reduced upon oral or topical treatment with PHF (all p < 0.05). Gallic acid, chlorogenic acid and berberine contents (w/w) in PHF were found to be 0.479%, 1.201% and 0.022%, respectively. Gallic acid and chlorogenic acid could suppress the release of pro-inflammatory cytokine IL-6 and chemokine CCL7 and CXCL8, respectively, in IL-31- and IL-33-treated eosinophils-dermal fibroblasts co-culture; while berberine could suppress the release of IL-6, CXCL8, CCL2 and CCL7 in the eosinophil culture and eosinophils-dermal fibroblasts co-culture (all p < 0.05). These findings suggest that PHF can ameliorate allergic inflammation and attenuate the activation of eosinophils.
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http://dx.doi.org/10.3390/molecules21040519DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6274171PMC
April 2016

The Pathogenesis of Nonarteritic Anterior Ischemic Optic Neuropathy.

Asia Pac J Ophthalmol (Phila) 2013 Mar-Apr;2(2):132-5

From the Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, PR China.

Although nonarteritic anterior ischemic optic neuropathy (NAION) is known to occur as a result of ischemic insult to the anterior portion of the optic nerve, its etiology and pathogenesis remain elusive. Because NAION is a nonfatal condition, acute, postmortem histopathologic analysis has never been undertaken. Animal models of NAION have been created with the use of an iodinated derivative of fluorescein, rose bengal. When rose bengal is stimulated with the use of a frequency-doubled neodymium-Yttrium aluminium garnet (YAG) laser diode, vascular endothelial damage may be induced in a precise and focal manner, within the anterior optic nerve. Primate and nonprimate animal models of NAION differ from the human pattern of NAION in the duration of the disease course, as well as the anatomy. The rat lamina cribrosa contains a differing connective tissue structure, which may result in a differing pathogenesis of ischemic insult. Optic disk swelling resolves within 5 days in rats and 14 days in primates; in humans, it is known to persist for up to 6 weeks. Animal models have nonetheless enabled a deeper understanding of the underlying pathologic processes in NAION.
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http://dx.doi.org/10.1097/APO.0b013e3182902e45DOI Listing
June 2015

Clinical characteristics of intermediate uveitis in Chinese patients.

Ocul Immunol Inflamm 2013 ;21(1):71-6

Department of Ophthalmology & Visual Sciences, the Chinese University of Hong Kong, Hong Kong Eye Hospital, Kowloon, Hong Kong.

Purpose: To describe the clinical characteristics of Chinese patients with intermediate uveitis (IU).

Methods: Retrospective review of patients with IU with at least 6 months follow-up.

Results: Seventy patients were identified and the mean follow-up was 59.7 months. The mean age at presentation was 33.1 years. Fifteen (21.4%) patients had disease onset before the age of 18 years; 91.4% of IU cases were considered idiopathic after investigations. At the last follow-up, 85 (74.6%) eyes retained vision of at least 20/40. Poor visual outcome was significantly associated with poor presenting visual acuity (p = .002), presence of epiretinal membrane or atrophic macular changes (p = .003), persistent cystoid macular edema (p = .015), and increased disease duration (odds ratio = 1.015 per month, p = .002). Pediatric patients were more likely to have bilateral (p = .003) and chronic disease (p < .001).

Conclusions: IU in Chinese patients was mainly idiopathic, with good visual outcomes in most patients after appropriate treatment.
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http://dx.doi.org/10.3109/09273948.2012.736587DOI Listing
July 2013

Complement factor H and interleukin gene polymorphisms in patients with non-infectious intermediate and posterior uveitis.

Mol Vis 2012 11;18:1865-72. Epub 2012 Jul 11.

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China.

Objective: To investigate the associations of complement factor H (CFH), KIAA1109, and interleukin-27 (IL-27) gene polymorphisms in patients with non-infectious intermediate and posterior uveitis.

Methods: The study cohort consisted of a total of 95 Chinese non-infectious uveitis patients, including 38 patients with intermediate uveitis (IU), 38 patients with Vogt-Koyanagi-Harada disease (VKH), and 19 patients with Behçet's disease and 308 healthy controls. The genotypes of CFH-rs800292, KIAA1109-rs4505848, and IL27-rs4788084 were determined using TaqMan single nucleotide polymorphism genotyping assays.

Results: The frequency of carriers of G allele for CFH-rs800292 was significantly higher in patients with non-infectious intermediate and posterior uveitis than in controls (GG/AG versus AA; p=0.02). No significant association was found between uveitis and both KIAA1109-rs4505848 and IL27-rs4788084. In stratified analysis by gender, the frequency of carriers with G allele for KIAA1109-rs4505848 was significantly higher in male uveitis patients than in male controls (GG/AG versus AA; p=0.034). There was no significant difference in allelic and genotypic frequencies for CFH-rs800292 and IL27-rs4788084 in either male or female groups. In addition, higher frequency of KIAA1109-rs4505848 G allele was found in Behçet's disease patients compared with controls and IU patients (p=0.01 and p=0.003, respectively).

Conclusions: Our results demonstrated that CFH-rs800292 and KIAA1109-rs4505848 are associated with non-infectious intermediate and posterior uveitis. Moreover, gender susceptibility for uveitis might be involved in the KIAA1109 gene and the KIAA1109-rs4505848 polymorphism might be associated with the development of Behçet's disease.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3413425PMC
December 2012

Acute and subacute inflammation of the optic nerve and its sheath: clinical features in Chinese patients.

Hong Kong Med J 2012 Apr;18(2):115-22

Department of Ophthalmology, Hong Kong Eye Hospital, 147K Argyle Street, Kowloon, Hong Kong.

Objective: Inflammation of the optic nerve (optic neuritis) and its sheath (optic perineuritis) can have similar initial clinical presentations. They are less well-defined in the Chinese than in Caucasians, and the aetiology of optic neuritis may also differ depending on ethnicity. The aim of our study was to document the clinical features of acute/subacute optic neuritis/optic perineuritis in Chinese patients.

Design: Retrospective case series.

Setting: Hong Kong Eye Hospital, Hospital Authority.

Patients: Records of all patients presenting to the Hong Kong Eye Hospital between 2005 and 2008, with their first episode of optic neuritis/optic perineuritis with onset of symptoms within 30 days, were reviewed.

Main Outcome Measures: Disease aetiology, clinical features and outcomes.

Results: Twenty-nine patients were included (M:F=13:16), with a mean age of 46 years at presentation. Among these, 25 had optic neuritis and four had optic perineuritis; four presented with bilateral optic neuritis. Among the optic neuritis group, 17 (68%) were idiopathic, seven (28%) were related to multiple sclerosis, and one (4%) had neuromyelitis optica. Poor visual outcome in the optic neuritis group was associated with poor visual acuity at presentation and poor visual acuity at the nadir.

Conclusion: Optic perineuritis and neuromyelitis optica-related optic neuritis were more commonly encountered in our study of Hong Kong Chinese patients than in Caucasian populations. Even in Chinese patients with 'typical' optic neuritis, neuro-imaging and further investigations may be warranted to exclude optic perineuritis/neuromyelitis optica, since Chinese ethnicity is itself an atypical feature. Where neuro-imaging is not readily available, intravenous methylprednisolone may be considered as initial treatment to cover both optic neuritis/optic perineuritis in patients with severe visual loss.
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April 2012

Combined high-dose sub-tenon triamcinolone, intravitreal bevacizumab, and laser photocoagulation for refractory diabetic macular edema: a pilot study.

Retina 2012 Apr;32(4):672-8

Department of Ophthalmology &Visual Sciences, The Chinese University of Hong Kong, Hong Kong.

Purpose: To study the efficacy and safety of triple therapy (sub-Tenon triamcinolone [∼70 mg], intravitreal bevacizumab [1.25 mg], and focal/grid laser) for refractory diabetic macular edema.

Method: Twenty-nine eyes of 29 patients who received triple therapy were monitored for central foveal thickness, best-corrected visual acuity (BCVA), and side effects over a 1-year period. Their results were compared with a focal/grid laser historical control group of 18 eyes (18 patients).

Results: In the triple therapy group, mean central foveal thickness significantly reduced from baseline value of 441 μm to 298 μm at Month 12 (P < 0.001), but there was no significant change of BCVA. In the control group, there were no sustained significant changes of central foveal thickness or BCVA. A subgroup analysis of 7 eyes in the triple therapy group with baseline BCVA of ≤20/100 showed significant BCVA improvements from 4 weeks to 9 months. The maximum improvement was achieved at 6 months, when the mean BCVA improved by 9.5 Early Treatment Diabetic Retinopathy Study letters from baseline. Intraocular pressure rise (31.0%), partial ptosis (17.2%), and significant cataractogenesis (8.7%) were encountered in the triple therapy group but not in the control group.

Conclusion: Sustained reduction of central foveal thickness was achieved with triple therapy over the 1-year study period. Significant visual improvement was seen only in patients with worse baseline BCVA, but not in the triple therapy group as a whole. Significant side effects of intraocular pressure rise, ptosis, and cataractogenesis were encountered in the triple therapy group.
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http://dx.doi.org/10.1097/IAE.0b013e31823043c6DOI Listing
April 2012

Review of Clinical Features, Microbiological Spectrum, and Treatment Outcomes of Endogenous Endophthalmitis over an 8-Year Period.

J Ophthalmol 2012 23;2012:265078. Epub 2012 Feb 23.

Department of Ophthalmology & Visual Sciences, The Chinese University of Hong Kong, Hong Kong.

Purpose. To evaluate the clinical features, microbiological spectrum, and treatment outcomes of endogenous endophthalmitis. Methods. Retrospective review of consecutive cases with infective endogenous endophthalmitis presenting from 2000 to 2007. The main outcome measure was the visual outcome at the latest follow-up visit. Other outcome measures included microbiological investigations, anatomical and clinical outcomes. Results. 22 eyes of 21 patients were included, and the mean follow-up duration was 2.7 years. Eyes with fungal endogenous endophthalmitis were more likely to have visual acuity of finger counting or better at presentation compared with those with bacterial endogenous endophthalmitis (odds ratio = 15.0, P = 0.013). Gram-negative microorganisms accounted for 50% of infections, while fungal and gram-positive organisms accounted for 27.3% and 22.7%, respectively. Despite treatment, the visual outcome was poor in general as 10 (45.5%) eyes had no light perception at the latest follow-up visit and 6 (27.3%) eyes required enucleation or evisceration. Contrary to previous studies, fungal endogenous endophthalmitis did not appear to have better visual outcome compared with bacterial endogenous endophthalmitis. Conclusion. Gram-negative microorganisms were the main causative pathogens of endogenous endophthalmitis in Hong Kong. The visual prognosis of endogenous endophthalmitis is generally poor as almost 50% of eyes were blind despite treatment.
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http://dx.doi.org/10.1155/2012/265078DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3594912PMC
March 2013

CFH 184G as a genetic risk marker for anterior uveitis in Chinese females.

Mol Vis 2011 13;17:2655-64. Epub 2011 Oct 13.

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China.

Objective: To investigate the association of three single nucleotide polymorphisms (SNPs) in the complement factor H (CFH), KIAA1109, and interleukin-27 (IL-27) genes in patients with anterior uveitis (AU).

Methods: A case-control study was performed in 98 Chinese AU patients and 308 healthy controls. Three SNPs including CFH-rs800292, KIAA1109-rs4505848, and IL27-rs4788084 were detected using TaqMan SNP Genotyping Assays. Analyses were also stratified according to gender, clinical features and human leukocyte antigen (HLA)-B27 status of the patients.

Results: No significant association was found between all three SNPs and AU. However, when stratified by gender, there were significant increases in the frequency of the CFH-rs800292 184G allele and GG homozygosity in female patients compared with control subjects (p=0.003 and p=0.009, respectively). Similar association was not detected in males. No significant association was found between AU and KIAA1109-rs4505848 or IL27-rs4788084 even stratified by gender. There was no significant difference in genotypes of AU patients stratified by various clinical features. Subgroup analyses showed that all three SNPs (rs800292, rs4505848, and rs4788084) were not associated with AU in HLA-B27-positive patients, neither in HLA-B27-negative patients.

Conclusions: Our results showed an association between AU and CFH polymorphism in Chinese female patients but not in males, indicating gender-specific genetic differences in CFH. Gender should be considered in genetic studies of anterior uveitis even extending to other immunologic diseases.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3209418PMC
February 2012

Ophthalmic manifestations and risk factors for mortality of HIV patients in the post-highly active anti-retroviral therapy era.

Clin Exp Ophthalmol 2011 Mar 19;39(2):99-104. Epub 2010 Oct 19.

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Hong Kong, China.

Background: To evaluate the ophthalmic manifestations and risk factors for mortality in HIV patients in the post-highly active anti-retrovirus therapy (HAART) era.

Design: Retrospective study.

Samples: 151 patients with HIV infection.

Methods: Review of all HIV patients who have attended the Hong Kong Eye Hospital between 2000 and 2007.

Main Outcome Measures: Ocular findings especially opportunistic infections and medical information including mortality during follow up.

Results: At presentation, 139 (92.1%) patients were already diagnosed with HIV and 58 (41.7%) had an AIDS indicator condition. Fifty-one (33.8%) patients had HIV-related eye disease on presentation and the leading manifestations were cytomegalovirus (CMV) retinitis and HIV microangiopathy. Low baseline CD4 cell count <100 cells/L was significantly related with HIV-related ophthalmic manifestations and CMV retinitis at presentation (P < 0.013). 105 patients were followed for 6 months or more and the mean follow-up was 4.8 years. There was no significant change in visual acuity compared with baseline (P = 0.13). 20 (19.0%) patients had one eye with final visual acuity of 20/200 or worse and the leading cause for poor vision was CMV retinitis. 11 (10.5%) patients died during the follow-up due to complications of HIV/AIDS. The presence of HIV retinal microangiopathy was significantly associated with mortality (P = 0.005).

Conclusions: CMV retinitis remains the main HIV-related ocular disease in the post-HAART era. HIV retinal microangiopathy might be an important prognostic factor for mortality. Appropriate ophthalmic monitoring is justified to detect for ophthalmic complications in HIV patients regardless of HAART use in order for prompt initiation of treatment.
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http://dx.doi.org/10.1111/j.1442-9071.2010.02400.xDOI Listing
March 2011

Intravitreal dexamethasone for diabetic macular edema: a pilot study.

Ophthalmic Surg Lasers Imaging 2010 Jan-Feb;41(1):26-30

Department of Ophthalmology & Visual Sciences, The Chinese University of Hong Kong, Hong Kong, People's Republic of China.

Background And Objective: To determine the response and safety profile of intravitreal dexamethasone in treating diabetic macular edema.

Patients And Methods: In this prospective pilot study, 12 eyes of 12 patients with diabetic macular edema were randomized to receive a single injection of 0.4 mg (n = 6) or 0.8 mg (n = 6) of intravitreal dexamethasone. The outcome measures were changes in best-corrected visual acuity and central foveal thickness on optical coherence tomography. Side effects were monitored.

Results: The 3-month results were reported. In both dosage groups, there were transient improvements in best-corrected visual acuity and central foveal thickness, but the changes were not significant at any time point (best-corrected visual acuity: P > or = 0.14; central foveal thickness: P > or = .08). No significant side effects were observed, except one eye developed a peak intraocular pressure of greater than 21 mm Hg.

Conclusion: A single injection of intravitreal dexamethasone (0.4 or 0.8 mg) did not have significant beneficial effects on diabetic macular edema within 3 months from injection in this small pilot study.
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http://dx.doi.org/10.3928/15428877-20091230-05DOI Listing
March 2010

Association of NR2E3 but not NRL mutations with retinitis pigmentosa in the Chinese population.

Invest Ophthalmol Vis Sci 2010 Apr 20;51(4):2229-35. Epub 2009 Nov 20.

Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.

Purpose. Mutations in the NR2E3 and NRL genes have been implicated in both autosomal dominant and autosomal recessive retinitis pigmentosa (RP). In this study, the mutation profiles of these two genes were investigated in Chinese RP patients. Methods. In 172 RP patients and 360 normal control subjects (180 from Hong Kong and 180 from Beijing), the coding exons and the exon-intron boundaries of NR2E3 and NRL were screened by direct DNA sequencing after PCR. Association analysis was performed for common single-nucleotide polymorphisms (SNPs), whereas in silico programs were used for analysis of rare missense variants. Results. In NR2E3, 14 novel sequence changes have been identified. Two missense variants, p.G56R and p.V118M, were exclusively found in RP patients with frequencies at 1.2% (2/172) and 1.7% (3/172), respectively. All five patients were found to be heterozygous for these two mutations. Computational analysis suggested functional defects on the NR2E3 protein, indicating disease-causing roles. The p.E121K variant of NR2E3, which reportedly caused enhanced S-cone syndrome (ESCS) in Caucasians, was found concurrently in RP patients (13.4%) and control subjects from Hong Kong (10.5%) and Beijing (12.8%). In NRL, six novel sequence changes were identified, none of them associated with RP. Conclusions. In this study, NR2E3 mutations (p.G56R, p.V118M) were found to be responsible for approximately 2.9% of overall RP in Chinese patients, comparable to the contributions of RHO and RP1 mutations. The p.E121K in NR2E3 is a common SNP in the Chinese, suggesting another genetic or environmental factor is involved in its causative role in ESCS in Caucasians.
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http://dx.doi.org/10.1167/iovs.09-4299DOI Listing
April 2010

Factors associated with variability in response of diabetic macular oedema after intravitreal triamcinolone.

Clin Exp Ophthalmol 2009 Aug;37(6):602-8

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong.

Purpose: To identify factors associated with variability in anatomical and functional response of diabetic macular oedema (DMO) after 4 mg of intravitreal triamcinolone acetonide (ivTA), and for recurrence of macular oedema.

Design: Pooled analysis of individual data from two randomized controlled trials.

Methods: This was a multicentre study involving 107 eyes with DMO administered 4 mg ivTA. Predictive factors for response to treatment were evaluated with linear regression analysis. Factors associated with time to recurrence of oedema were studied with Cox proportional hazards modelling. Main outcome measures were maximum improvement in optical coherence tomography (OCT)-measured central foveal thickness (CFT) and best-corrected visual acuity (BCVA), final CFT and BCVA at 12 months and time to oedema recurrence.

Results: Greater reduction of retinal thickening occurred in eyes with worse baseline thickening (P < 0.001). There was also greater improvement of visual acuity in eyes with poorer preoperative BCVA levels (P < 0.001). Age, duration of oedema and previous macular laser treatment had no significant effect on maximal BCVA or CFT improvement. Eyes given 4 mg triamcinolone alone were more likely to develop recurrence of oedema at 12 months than those given a combination of 4 mg triamcinolone plus sequential laser (hazard ratio 2.60 [95% confidence interval: 1.45-4.67]).

Conclusion: Baseline OCT-measured retinal thickening and BCVA are important predictors of maximal anatomical and functional response of DMO to ivTA, respectively. Combination treatment strategy using sequential laser therapy may have a role in delaying recurrence of oedema after triamcinolone.
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http://dx.doi.org/10.1111/j.1442-9071.2009.02104.xDOI Listing
August 2009

Manganese superoxide dismutase and chemokine genes polymorphisms in chinese patients with anterior uveitis.

Invest Ophthalmol Vis Sci 2009 Dec 23;50(12):5596-600. Epub 2009 Jul 23.

Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong.

Purpose: To investigate the association of single-nucleotide polymorphisms (SNPs) in the manganese superoxide dismutase (MnSOD) and two chemokine genes (CCL2 and CCL5) in patients with anterior uveitis (AU).

Methods: Seventy-nine Chinese patients with acute AU were recruited, and genotyping of four SNPs including MnSOD 47, CCL2 -2518, CCL2 -2076, and CCL5 -403 alleles was performed with SNP genotyping assays. The genotype and allele frequencies were compared between patients with AU and 206 healthy control subjects. Analyses were also stratified according to the HLA-B27 status of the patients.

Results: There were significant increases in the frequency of the AA homozygosity in the MnSOD 47 SNP (P = 0.049) and in the CCL2 -2518G allele frequency and GG homozygosity in patients with AU compared with control subjects (P = 0.017 and P = 0.024, respectively). No significant association was found between AU with the CCL2 -2076 and CCL5 -403 SNPs. Subgroup analyses showed that the MnSOD 47A polymorphism was significantly associated with AU in HLA-B27-positive patients, but not in HLA-B27-negative patients, whereas the CCL2 -2518G polymorphism was significantly associated with AU in HLA-B27-negative patients, but not in HLA-B27-positive patients.

Conclusions: The 47A polymorphism in the MnSOD gene and the -2518G polymorphism in the CCL2 gene are associated with the development of AU in HLA-B27-positive and -negative Chinese patients, respectively. Further studies to evaluate the interactions of the HLA-B27 status and these SNPs are warranted.
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http://dx.doi.org/10.1167/iovs.09-3661DOI Listing
December 2009

Efficacy of 1.25 MG versus 2.5 MG intravitreal bevacizumab for diabetic macular edema: six-month results of a randomized controlled trial.

Retina 2009 Mar;29(3):292-9

Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Hong Kong.

Purpose: To evaluate the efficacy of intravitreal injections of two different dosages of bevacizumab (Avastin) for treating diffuse diabetic macular edema.

Methods: Fifty-two eyes of 52 patients with diabetic macular edema were randomized to receive three monthly intravitreal injections of 1.25 mg or 2.5 mg bevacizumab. Patients were observed for 6 months and optical coherence tomography central foveal thickness, logMAR best-corrected visual acuity (BCVA), and adverse events were assessed.

Results: Forty-eight eyes of 48 patients completed the 6-month follow-up and were analyzed. Significant mean central foveal thickness reductions were observed in both groups at all follow-up visits (P < 0.013). Significant improvements between baseline and 6-month mean logMAR BCVAs were seen, with the mean logMAR BCVA improved from 0.63 to 0.52 in the 1.25 mg group and 0.60 to 0.47 in the 2.5 mg group. No significant difference in BCVA was observed between the two groups at any time point (P > 0.56). Subgroup analysis showed that intravitreal bevacizumab seemed to be more effective in eyes without any previous diabetic macular edema treatment.

Conclusions: Three monthly intravitreal bevacizumab injections resulted in significant reduction in central foveal thickness and improvements in BCVA in diabetic macular edema patients. Both 1.25 mg and 2.5 mg seemed to have similar treatment efficacy.
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http://dx.doi.org/10.1097/IAE.0b013e31819a2d61DOI Listing
March 2009

Peripapillary nerve fiber layer thickness measured by optical coherence tomography in patients with no light perception from long-standing nonglaucomatous optic neuropathies.

J Neuroophthalmol 2007 Sep;27(3):176-9

Neuro-Ophthalmology Unit (NRM), Wilmer Eye Institute, The Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MD 21287, USA.

Background: The residual peripapillary retinal nerve fiber layer thickness (PRNFLT) corresponding to no light perception vision from long-standing nonglaucomatous optic neuropathies has not been documented. Such a benchmark would be useful information because PRNFLT is being used as an indicator of the visual recovery potential in patients with optic neuropathies.

Methods: By means of optical coherence tomography (OCT) using a fast RNFL thickness protocol, we determined the PRNFLT in 8 patients with no light perception (NLP) for at least 1 year from acquired nonglaucomatous optic neuropathies. All patients underwent an assessment of visual acuity, color vision, visual field, pupillary reactions to light stimulation, and ophthalmoscopy.

Results: Four of the 8 patients had a normal fellow eye. The average PRNFLT in the 4 normal eyes was 97.90 microm (range 94.82-100.89 microm), whereas the average PRNFLT in 8 of the 9 eyes with NLP was 45.42 microm (range 37.65-51.46 microm).

Conclusions: Eyes with long-standing NLP vision from nonglaucomatous optic neuropathies retain a residual PRNFLT of about 45 microm as measured by OCT. This should be taken into consideration when using PRNFLT to assess visual prognosis in patients with poor vision from various optic neuropathies.
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http://dx.doi.org/10.1097/WNO.0b013e31814b1ac4DOI Listing
September 2007

Intravitreal triamcinolone plus sequential grid laser versus triamcinolone or laser alone for treating diabetic macular edema: six-month outcomes.

Ophthalmology 2007 Dec 25;114(12):2162-7. Epub 2007 Apr 25.

Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Hong Kong, China.

Objective: To evaluate the efficacy of sequential intravitreal triamcinolone acetonide (TA) injection followed by grid laser photocoagulation for treating diabetic macular edema (DME).

Design: Prospective, 3-armed, randomized clinical trial.

Participants: One hundred eleven eyes of 111 patients with DME involving the fovea.

Intervention: Patients were randomized to grid laser photocoagulation (37 eyes), 4 mg of intravitreal TA (38 eyes), or 4 mg of intravitreal TA combined with sequential grid laser about 1 month later (36 eyes).

Main Outcome Measures: Central foveal thickness (CFT) as measured by optical coherence tomography, logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA), and side effect profiles. The 6-month results are reported.

Results: All patients completed 6 months' follow-up. Baseline mean (+/- standard deviation) CFTs were 385+/-100 microm, 396+/-91 microm, and 424+/-108 microm for the laser, intravitreal TA, and combined groups, respectively (P = 0.24). After treatment, significant CFT reductions were noted in both the intravitreal TA and combined groups at all follow-up visits (P<0.01) but not in the laser group. Mean CFT improved significantly to minimums of 267+/-75 microm and 256+/-73 microm for the intravitreal TA and combined groups, respectively, but the difference between the 3 groups was not significant at 6 months. The standardized change in macular thickening at 17 weeks was significantly greater in the combined group versus the intravitreal TA group (P = 0.007), suggesting that combined treatment might prolong the effects of intravitreal TA. Mean baseline logMAR BCVAs were 0.64+/-0.37, 0.72+/-0.34, and 0.69+/-0.34 in the laser, intravitreal TA, and combined groups, respectively (P = 0.67). Best-corrected visual acuity improved significantly at 4 and 9 weeks for the intravitreal TA group but did not change significantly in the other 2 groups. No significant difference in BCVA was observed between the 3 groups at any time point.

Conclusions: Contrary to the results of a recent study, combined treatment of intravitreal TA plus grid laser did not yield better CFT reduction or BCVA improvement at 6 months than intravitreal TA alone. Grid laser alone was significantly worse than the 2 other treatment modalities.
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http://dx.doi.org/10.1016/j.ophtha.2007.02.006DOI Listing
December 2007

Topical atropine in retarding myopic progression and axial length growth in children with moderate to severe myopia: a pilot study.

Jpn J Ophthalmol 2007 Jan-Feb;51(1):27-33. Epub 2007 Feb 9.

Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Kowloon, Hong Kong, People's Republic of China.

Purpose: To study the safety and efficacy of topical 1% atropine eye ointment in retarding myopic progression in children with moderate to severe myopia.

Methods: This was an interventional control study. Children (aged 5-10 years) with myopia of -3.00 diopters (D) or more were treated with 1% atropine ointment once daily for 1 year. Baseline and regular assessments of refractive errors by cycloplegic autorefraction and of axial length were done by ultrasound biometry, and the results were compared with data of control subjects.

Results: Twenty-three children (mean age: 7.4 +/- 1.6 years) with moderate to severe myopia, being treated in the Hong Kong Eye Hospital of the Chinese University of Hong Kong, were recruited into the atropine group, and 23 children from the same eye clinic were matched with the study subjects with respect to age, sex, and initial spherical equivalent refraction, as controls. The initial refractive errors were -5.18 +/- 2.05 D and -5.12 +/- 2.33 D in the atropine and the control groups, respectively (P = 0.934). Myopic progression was significantly less (P = 0.005) in the atropine group (+0.06 +/- 0.79 D) than in the control group (-1.19 +/- 2.48 D). Axial length increase was also significantly smaller in the atropine group (0.09 +/- 0.19 mm) than in the control group (0.70 +/- 0.63 mm) (P = 0.004). One child (4.3%) developed an allergic reaction. No other major adverse effects related to the treatment were noted.

Conclusion: Topical 1% atropine ointment is a safe and effective treatment for retarding myopic progression in moderate to severe myopia. Further large-scale randomised controlled study with longer follow-up seems warranted.
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http://dx.doi.org/10.1007/s10384-006-0380-7DOI Listing
April 2007
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