EDI-OCT evaluation of choroidal thickness in retinitis pigmentosa.

PURPOSE: To evaluate choroidal thickness (CT) in retinitis pigmentosa (RP) using enhanced depth imaging (EDI) optical coherence tomography (OCT). METHODS: A retrospective analysis of a group of patients with RP who underwent EDI-OCT was performed. Choroidal thickness measurements were compared with those of age- and sex-matched healthy subjects. In the RP group, the possible association between subfoveal CT and some clinical parameters (visual acuity, age, age at disease onset, duration of the disease, macular thickness, visual field loss, electroretinography [ERG]) was evaluated. RESULTS: The study recruited 39 patients with RP with an average age of 43.3 ± 11.3 years while the control group consisted of 73 healthy subjects with an average age of 42.9 ± 12.10 years. On average, CT was significantly thinner in the RP group compared to the controls (p<0.0001). In the RP group, we could not find any significant association between CT and the considered clinical parameters even if there was a trend for decreasing CT with increasing age (r = -0.23, p = 0.096). In the control group, subfoveal CT showed a slightly significant correlation with age (r = -0.21, p = 0.04) but not with macular thickness and visual acuity. CONCLUSIONS: In our series, CT was significantly lower in the RP group in comparison with the controls, as measured by EDI-OCT, but did not correlate with age, age at onset, duration of the disease, macular thickness, visual acuity, visual field loss, or ERG responses. Although the clinical implications of choroidal changes in RP have not yet been clearly determined, the evaluation of choroidal features may provide information that could be useful to clarify the pathophysiology of the disease.

Reading Ability and Quality of Life in Stargardt Disease.

PURPOSE: To study the reading performance of patients with Stargardt disease (STGD) and the relationship between clinical vision measurements and vision-related quality of life (VRQOL). METHODS: We studied both eyes of 16 patients with STGD. Each patient was examined for best-corrected visual acuity (Early Treatment Diabetic Retinopathy Study [ETDRS]), reading ability (MNREAD and REX charts), contrast sensitivity (Pelli-Robson charts), fixation study (MP1 microperimeter), and VRQOL (25-item National Eye Institute Visual Function Questionnaire [NEI VFQ-25]). The correlation pattern among these variables was examined and an exploratory factor analysis was used to investigate dimensionality of both visual function and VRQOL. RESULTS: Mean ETDRS visual acuity was about 20/160 (0.9 logMAR). All studied psychophysical measures were highly or moderately correlated with MNREAD reading speed (p<0.05 level). A similar correlation was found between psychophysical measures and VRQOL, which was higher for MNREAD measures of acuity (r = -0.75) and speed (r = 0.74). Accordingly, exploratory factor analysis suggested that a single latent dimension explained most of the variance of vision psychophysical measures as well as of VRQOL. CONCLUSIONS: We propose that reading ability should be assessed in patients with STGD, since we found that both MNREAD reading speed and visual acuity are strong determinants of quality of life. The observed relation between reading ability and VRQOL in STGD suggests that in these patients appropriate low vision rehabilitation can improve both reading performance and consequently VRQOL. Finally, our data support the use of reading speed and visual acuity as important outcome measures for monitoring STGD progression.