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Wai-Man Chan

Publications and source records attributed to Wai-Man Chan.

86 records · Page 5Linked to original sources
PubMed2003

Infective endophthalmitis caused by Bacillus cereus after cataract extraction surgery.

We describe a 72-year-old Chinese man who developed fulminant Bacillus cereus endophthalmitis 36 h after an uneventful surgery for cataract extraction. Clinical progression of disease was extremely rapid, in spite of early vitrectomy and intravitreal injection of antibiotics. Results of Gram staining showed gram-positive bacilli, and the culture was positive for B. cereus. Endophthalmitis is rare after cataract surgery (cumulative probability within 1 year, approximately 0.08%), and cases caused by B. cereus are even less common. The prognosis and plan of treatment are discussed.

Bacillaceae Infections↗
PubMed2003

Successful photodynamic therapy with verteporfin for recurrent choroidal neovascularization beneath the new fovea after macular translocation surgery with 360-degree retinotomy.

PURPOSE: To report a case of successfully treated recurrent choroidal neovascularization after macular translocation surgery with 360-degree retinotomy by photodynamic therapy with verteporfin. DESIGN: Interventional case report. METHODS: A 76-year-old man developed recurrent choroidal neovascularization at the new fovea after macular translocation surgery with 360-degree retinotomy. RESULTS: Two sessions of photodynamic therapy were applied, which resolved the choroidal neovascularization. Best-corrected visual acuity improved to 20/50 at the 6 and 12 months follow-up. CONCLUSION: Photodynamic therapy may be an option for treatment of recurrent choroidal neovascularization in the new subfoveal region after macular translocation surgery with 360-degree retinotomy.

Aged↗
PubMed2003

Photodynamic therapy with verteporfin in laser-induced choroidal neovascularization.

PURPOSE: To report a case of laser-induced choroidal neovascularization (CNV) treated with verteporfin photodynamic therapy. DESIGN: Interventional case report. METHODS: A patient developed CNV in the macular area of the left eye 2 years following grid laser for macular edema secondary to branch retinal vein occlusion. RESULTS: The CNV was controlled with one session of photodynamic therapy. Lesion decreased in size, contracting to a smaller subretinal fibrotic scar. Vision improved from 20/200 to 20/100, and there was no recurrence at 2-year follow-up. No complications were encountered. CONCLUSION: Laser-induced CNV can be safely and effectively treated by photodynamic therapy.

Adult↗
PubMed2003

Photodynamic therapy with verteporfin for subfoveal idiopathic choroidal neovascularization: one-year results from a prospective case series.

OBJECTIVE: To study the safety and efficacy of photodynamic therapy (PDT) with verteporfin in treating subfoveal choroidal neovascularization (CNV) of idiopathic cause. DESIGN: A prospective, noncomparative, consecutive, open-label, two-center, interventional case series. PARTICIPANTS: Patients aged 50 years or younger with the diagnosis of idiopathic CNV by exclusion of other related causes together with the CNV extending under the geometric center of the foveal avascular zone. METHODS: Seventeen eyes from 17 patients received PDT with verteporfin according to a standardized protocol. Retreatment was considered if fluorescein leakage from the CNV was shown in fluorescein angiography at every 3-month follow-up. The visual, clinical, and angiographic responses were observed. Complications from treatment were monitored and documented. MAIN OUTCOMES MEASURES: The changes in the best-corrected visual acuity (BCVA) at the 1-year follow-up. The proportion of patients with improved (gained 2 lines or more), stable, and dropped (lost 2 lines or more) vision and the mean number of treatments required during the 1-year interval were measured. Complications were monitored and tabulated. RESULTS: Seventeen eyes with complete 1-year follow-up were analyzed. The mean logarithm of the minimum angle of resolution BCVA improved from 0.64 to 0.41 (Wilcoxon signed-ranks test, P = 0.007). Sixteen eyes (94%) had stable or improved vision. Only one patient (6%) had moderate loss of vision. The mean number of PDT treatment was 1.8 per eye over the 1-year period. Patients with smaller lesion size or active vascular CNV on presentation were more likely to have a final BCVA of 20/100 or better (Fisher's exact test, P = 0.006 and P = 0.015, respectively). No serious local or systemic complications were encountered. CONCLUSIONS: PDT seems to be a promising treatment strategy in achieving a stable or improved vision for subfoveal idiopathic CNV. The treatment was well tolerated. Further studies and longer follow-up are warranted to assess the long-term safety and efficacy of PDT compared with observation or other treatment modalities.

Adult↗
PubMed2002

Duane radial ray syndrome (Okihiro syndrome) maps to 20q13 and results from mutations in SALL4, a new member of the SAL family.

Duane syndrome is a congenital eye movement disorder characterized most typically by absence of abduction, restricted adduction, and retraction of the globe on attempted adduction. Duane syndrome can be coinherited with radial ray anomalies as an autosomal dominant trait, referred to as "Okihiro syndrome" or "Duane radial ray syndrome" (DRRS). We ascertained three pedigrees with DRRS and mapped their disease gene to a 21.6-cM region of chromosome 20 flanked by markers D20S888 and D20S102. A new member of the SAL family of proposed C(2)H(2) zinc finger transcription factors, SALL4, falls within the region. Mutation analysis of SALL4 in the three pedigrees revealed one nonsense and two frameshift heterozygous mutations. SALL4 represents the first identified Duane syndrome gene and the second malformation syndrome resulting from mutations in SAL genes and likely plays a critical role in abducens motoneuron development.

Chromosome Mapping↗
PubMed2002

Congenital fibrosis of the vertically acting extraocular muscles maps to the FEOM3 locus.

The diagnosis of congenital fibrosis of the extraocular muscles (CFEOM) encompasses several different inherited strabismus syndromes characterized by congenital restrictive ophthalmoplegia affecting extraocular muscles innervated by the oculomotor and/or trochlear nerves. The OMIM database (http://www.ncbi.nlm.nih.gov/Omim/) currently contains four familial CFEOM phenotypes: CFEOM1-3, which map to the FEOM1-3 loci (MIM 135600, 602078, 604361), respectively, and congenital fibrosis of the vertically acting extraocular muscles (MIM 600638), reported in a single family without a corresponding genotype. We have had the opportunity to study the reported family with this fourth phenotype and now demonstrate that their phenotype can be reclassified as CFEOM3 and that it maps to FEOM3, flanked by D16S498 to 16qter, with a maximum lod score of 6.0.

Chromosomes, Human, Pair 16↗
PubMedDate not supplied

Photodynamic therapy in macular diseases of asian populations: when East meets West.

PURPOSE: We reviewed the indications, safety, and efficacy of photodynamic therapy with verteporfin in various macular diseases and vasculopathies, which are common in Asian populations, and compared the outcomes of photodynamic therapy in Asian patients with the outcomes in Caucasian patients. METHODS: Relevant clinical and laboratory original articles, case reports, and review articles that have been published in the literature between January 1999 and October 2004 were searched in Medline. The potential differences in the response to photodynamic therapy between Asian and Caucasian patients were evaluated. Articles in foreign languages with English abstracts were included. RESULTS: Macular diseases commonly seen in Asian populations, including choroidal neovascularization (CNV) of age-related macular degeneration, secondary to pathologic myopia or from an idiopathic cause, and choroidal vasculopathies such as central serous chorioretinopathy and polypoidal choroidal vasculopathy were included in the review. The results were tabulated and the differences with Caucasian populations were compared and highlighted. CONCLUSION: Photodynamic therapy has been found to be an effective and noninvasive treatment for various subfoveal CNV and choroidal vasculopathies of the macula. Diverse behavior in different ethnic groups is observed.

Asian People↗
PubMedDate not supplied

The clinical applications of multifocal electroretinography: a systematic review.

Multifocal electroretinography (mfERG) is an investigation that can simultaneously measure multiple electroretinographic responses at different retinal locations by cross-correlation techniques. mfERG therefore allows topographic mapping of retinal function in the central 40-50 degrees of the retina. The strength of mfERG lies in its ability to provide objective assessment of the central retinal function at different retinal areas within a short duration of time. Since the introduction of mfERG in 1992, mfERG has been applied in a large variety of clinical settings. This article reviews the clinical applications of mfERG based on the currently available evidence. mfERG has been found to be useful in the assessment of localized retinal dysfunction caused by various acquired or hereditary retinal disorders. The use of mfERG also enabled clinicians to objectively monitor the treatment outcomes as the changes in visual functions might not be reflected by subjective methods of assessment. By changing the stimulus, recording, and analysis parameters, investigation of specific retinal electrophysiological components can be performed topographically. Further developments and consolidations of these parameters will likely broaden the use of mfERG in the clinical setting.

Electroretinography↗