A Meta-Analysis of Choroidal Thickness Changes in Unilateral Amblyopia

Purpose. To date, the topic of amblyopic changes remains controversial. Therefore, a systematic review and meta-analysis were carried out to evaluate choroidal changes in unilateral amblyopia. Methods. Major literature databases were searched for amblyopia-relevant studies. Using enhanced depth imaging optical coherence tomography (EDI-OCT), the primary outcome parameters examined were subfoveal choroidal thickness (SFCT) and different choroidal thickness (CT) positions. Efficacy estimates were evaluated by weighted mean difference (WMD) and 95% confidence interval (CI) for choroidal-associated changes. We performed subgroup analysis and metaregression analysis to examine potential sources of heterogeneity. Results. Eleven cross-sectional studies that included a total of 768 participants were identified. The amblyopic eye SFCT was thicker than that of the fellow and control (normal) eyes (WMDamblyopia versus fellow=49.24, 95% CI of 30.22 to 68.27, p<0.001; WMDamblyopia versus control=54.51, 95% CI of 32.17 to 76.85, p<0.001). There were no differences between the fellow and control eyes (WMD=13.81, 95% CI of 1.16 to 28.77, p=0.071). Subgroup and metaregression analyses indicated that the OCT type was the main source of heterogeneity. Conclusions. The CT in the amblyopic eyes was thicker than that in the fellow and control eyes

Differential dendritic shrinkage of and retinal ganglion cells in cats with chronic glaucoma.

PURPOSE. To study changes in the dendritic morphology of retinal ganglion cells (RGCs) in cats with experimental chronic glaucoma. METHODS. Chronic elevation of intraocular pressure (IOP) was produced by injecting endogenous ghost red blood cells into the unilateral anterior chamber of the feline eyes for 1 month. The morphologic features of retrograde-labeled RGCs by bilateral injection of horseradish peroxidase (HRP) into layers A and Aa1 of the lateral geniculate nucleus (LGN) were examined and compared between the normal and glaucomatous eyes. Nissl staining was used for measuring the change in cell density in the retina and the LGN. RESULTS. Quantitative analysis of 720 labeled ␣ and ␤ type RGCs showed that the cell density, body size, maximum dendritic field radius, total dendritic length, and number of branch bifurcations of dendrites decreased significantly in glaucomatous eyes compared with normal ones. The cell loss and shrinkage of dendrites in ␣ type ganglion cells in the retina was more pronounced than that in ␤ type cells. The cell density of all kinds of cells in the retina and LGN monotonically declined with time while IOP was elevated, and cell loss was more significant in large cells than in small ones. G laucoma is the most common cause of blindness except for cataracts. In most cases, glaucoma is characterized by an elevation of intraocular pressure (IOP), progressive changes in morphology of the optic disc and retinal axon layer, and visual field defects. Eventually, it makes the eye blind by killing retinal ganglion cells (RGCs). Many studies have shown that glaucoma and chronic elevation of IOP cause degeneration in the optic nerve fibers 1-4 and progressive loss of retinal ganglion cells. 4 -6 Weber et al. In the cat&apos;s retina, ␣ and ␤ ganglion cells are classically defined as distinct morphologic types that correspond to physiological Y-and X-type cells, respectively. Y (or ␣) cells have the largest soma, the largest dendritic field area, and the thickest dendrites and preferentially respond sensitively to stimuli of low contrast, low spatial frequency, and fast-moving patterns. In contrast, X (or ␤) cells have a medium soma, the smallest dendritic field area, and a bushy dendritic arbor and are sensitive to stimuli of higher contrast, fine structure, and relatively low velocity of motion. 10 -14 Both Y and X RGCs project separately to Y-and X-type relay cells in layers A and A1 of the dorsal lateral geniculate nucleus (LGN) and form the parallel pathway of visual information processing in the cat, 12-14 similar to the magno-and parvocellular pathways in the monkey&apos;s visual system. It is well-documented in monkeys with chronic glaucoma that large RGCs are more seriously damaged than small cells. 2-4 However, previous studies in our laboratory have demonstrated that in the cat, the Y-type ganglion cells in the retina and relay cells in the LGN are more tolerant than X cells to brief elevations of IOP. METHODS Animal Model of Chronic Glaucoma Fourteen adult cats weighing between 2 kg and 2.7 kg were used as experimental models of glaucoma. Their eyes were tested to ensure ophthalmic health. All the procedures for production of chronic elevated IOP were conducted according to the description by Quigley and Addicks. 18 The glutaraldehyde-fixed autogenous red cells in saline (1:1 in volume) of 0.3 mL was injected into the anterior chamber of the unilateral eye of a cat when another syringe was used to drain off the same volume of aqueous humor. The contralateral eye of each cat was used as the control. The IOP of each eye was repeatedly measured using a Schiotz tonometer in cats under ketamine anesthesia. The From th

Knocking Down Snrnp200 Initiates Demorphogenesis of Rod Photoreceptors in Zebrafish

Purpose. The small nuclear ribonucleoprotein 200 kDa (SNRNP200) gene is a fundamental component for precursor message RNA (pre-mRNA) splicing and has been implicated in the etiology of autosomal dominant retinitis pigmentosa (adRP). This study aims to determine the consequences of knocking down Snrnp200 in zebrafish. Methods. Expression of the Snrnp200 transcript in zebrafish was determined via whole mount in situ hybridization. Morpholino oligonucleotide (MO) aiming to knock down the expression of Snrnp200 was injected into zebrafish embryos, followed by analyses of aberrant splicing and expression of the U4/U6-U5 tri-small nuclear ribonucleoproteins (snRNPs) components and retina-specific transcripts. Systemic changes and retinal phenotypes were further characterized by histological study and immunofluorescence staining. Results. Snrnp200 was ubiquitously expressed in zebrafish. Knocking down Snrnp200 in zebrafish triggered aberrant splicing of the cbln1 gene, upregulation of other U4/U6-U5 tri-snRNP components, and downregulation of a panel of retina-specific transcripts. Systemic defects were found correlated with knockdown of Snrnp200 in zebrafish. Only demorphogenesis of rod photoreceptors was detected in the initial stage, mimicking the disease characteristics of RP. Conclusions. We conclude that knocking down Snrnp200 in zebrafish could alter regular splicing and expression of a panel of genes, which may eventually trigger rod defects

Association of OPA1 polymorphisms with NTG and HTG: a meta-analysis.

BACKGROUND: Genetic polymorphisms of the Optic atrophy 1 gene have been implicated in altering the risk of primary open angle glaucoma (POAG), especially the susceptibility to normal tension glaucoma (NTG), but the results remain controversial. METHODS: Multiple electronic databases (up to January 20, 2012) were searched independently by two investigators. A meta-analysis was performed on the association between Optic atrophy 1 polymorphisms (rs 166850 and rs 10451941) and normal tension glaucoma (NTG)/high tension glaucoma (HTG). Summary odds ratios (ORs) and 95% confidence intervals (CI) were estimated. RESULTS: Seven studies of 713 cases and 964 controls for NTG and five studies of 1200 cases and 971 controls for HTG on IVS8+4C>T (rs 166850) and IVS8+32T>C (rs10451941) were identified. There were significant associations between the OPA1 rs10451941polymorphism and NTG susceptibility for all genetic models(C vs. T OR = 1.26, 95% CI 1.09-1.47, p = 0.002; CC vs. TT: OR = 1.52, 95% CI 1.04-2.20, p = 0.029; CC vs. CT+TT: OR = 1.64, 95% CI 1.16-2.33, p = 0.005; CC+CT vs. TT: OR = 1.21, 95% CI 1.02-1.44, p = 0.032). However, no evidence of associations was detected between the OPA1 IVS8+32C>T polymorphism and POAG susceptibility to HTG. Similarly, clear associations between the rs 166850 variant and NTG were observed in allelic and dominant models (T vs. C OR = 1.52, 95% CI 1.16-1.99, p = 0.002; TT+TC vs. CC OR = 1.50, 95% CI 1.13-2.01, p = 0.006) but not to HTG. In subgroup analyses by ethnicity, we detected an association between both OPA1 polymorphisms and risk for NTG in Caucasians but not in Asians. By contrast, no significant findings were noted between OPA1 variants for HTG, either in Caucasians or in Asians. CONCLUSIONS: Both the IVS8+4C>T and IVS8+32T>C variants may affect individual susceptibility to NTG. Moreover, stratified analyses for NTG detecting the effects of both OPA1 polymorphisms seemed to vary with ethnicity. Further investigations are needed to validate the association

A novel de novo duplication mutation of PAX6 in a Chinese family with aniridia and other ocular abnormalities

Natural Science Foundation of Fujian Province [2010J06010]; Program for New Century Excellent Talents in Fujian Province University [JA10127]; Professor Academic Development Fund of Fujian Medical University [JS12003]; Key Program of Scientific Research of Fujian Medical University [09ZD016]Aniridia is a congenital panocular disorder caused by the mutations of the paired box gene-6 (PAX6). To investigate the clinical characterization and the underlying genetic defect in a Chinese family with aniridia and other ocular abnormalities, we recruited the family members who underwent ophthalmic examination. Two patients in this family, the proband and his affected son, both have bilateral aniridia, foveal hypoplasia and nystagmus. Moreover, the proband also had presenile cataracts, but his affected son did not show cataracts at the time of examination. Sequencing PAX6 revealed that a heterozygous duplication mutation c.95_105dup11, predicted to generate non-functional truncated protein at position Gly36 (p.G36X), was found in the affected individuals but not in any of the unaffected family members including the parents of the proband. Haplotype analysis showed that the proband and his affected son shared a common disease-related haplotype, which was arisen from the proband's unaffected father through crossing-over. In conclusion, we identified a novel de novo duplication mutation of PAX6 in the aniridia and other ocular abnormalities family. This mutation has occurred de novo on a paternal chromosome by direct duplication, which presumably results from replication slippage or unequal non-sister chromatids exchange during spermatogenesis

The ophthalmology surgical competency assessment rubric for strabismus surgery

PURPOSE: To produce an internationally valid tool to assess skill in performing strabismus surgery. METHODS: A panel of 7 content experts adapted a previously published tool for assessing phacoemulsification by using a modified Dreyfus scale of skill acquisition and providing behavioral descriptors for each level of skill in each category. The tools were then reviewed by 12 international content experts for their constructive comments. The main outcome measure was a consensus of the experts on the final rubric. RESULTS: Experts\u27 comments were incorporated, establishing face and content validity. CONCLUSIONS: The tool (Ophthalmology Surgical Competency Assessment Rubric for Strabismus Surgery (ICO-OSCAR: strabismus) has face and content validity. It can be used globally to assess strabismus surgical skill. Reliability and predictive validity are yet to be determined