Objective To observe the effects of local macular foveal photoreceptor defects on visual acuity.Methods Thirty-one patients (31 eyes) with photoreceptor defect in macular fovea (case group) diagnosed by spectral domain optical coherence tomography (SD-OCT) and 30 patients (30 eyes) age- and diopter- matched normal subjects (control group) were enrolled in this study. There were 22 eyes with full photoreceptor defects and 9 eyes with outer segment defects in case group. All subjects were examined for best corrected visual acuity (BCVA), slit-lamp microscopy, direct ophthalmoscope and SD-OCT. Independent sample t-test was used to compare central foveal thickness (CFT) between case group and control group. Difference of logMAR BCVA, CFT, maximum width and height of photoreceptor defects, defected area and residual retinal thickness in macular between patients with full photoreceptor defects and outer segment defects were also compared.Results The CFT of case group and control group were (225.32 plusmn;19.70),(240.02 plusmn;10.70) mu;m, the difference was not statistically significant (t=-1.96, P＞0.05). In full photoreceptor defects and outer segment defects patients, the mean logMAR BCVA were 0.22 plusmn;0.31, 0.32 plusmn;0.43; the mean CFT were (224.09 plusmn;20.57), (228.33 plusmn;18.17) mu;m; the maximum width of photoreceptor defects were (131.32 plusmn;108.18), (143.22 plusmn;66.93) mu;m; the mean defected area were (0.022 plusmn;0.054), (0.019 plusmn;0.019) mm2; the mean maximum height of photoreceptor defects were (77.41 plusmn;6.62), (44.89 plusmn;4.26) mu;m; the mean residual retinal thickness were (87.00 plusmn;20.31), (128.33 plusmn;23.54) mu;m respectively. There was no statistical significance between full photoreceptor defects and outer segment defects patients in the mean logMAR BCVA, CFT, maximum width of photoreceptor defects and defected area (t=-0.76, -0.538, -0.305, 0.166; P＞0.05), but there were significant difference in mean maximum width of photoreceptor defects and residual retinal thickness (t=12.72, -4.91;P＜0.05). Conclusions The local photoreceptor defects in macular fovea can lead to decrease of visual acuity. The wider the photoreceptor defects, the worse the visual acuity.
Citation： 刘杏,肖辉,钟毅敏,米兰,毛真,李媚. Effects of local foveal photoreceptor defect on visual acuity. Chinese Journal of Ocular Fundus Diseases, 2012, 28(4): 329-332. doi: Copy