National Centre of Services and Research for the Prevention of Blindness and Rehabilitation of Low Vision Patients, International Agency for Prevention of Blindness-IAPB Italia Onlus, Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS, Rome, Italy.
Department of Ophthalmology, Universita' Cattolica del Sacro Cuore, Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS, Rome, Italy.
Ophthalmic Physiol Opt. 2020 Nov;40(6):778-789. doi: 10.1111/opo.12726. Epub 2020 Sep 4.
There are conflicting reports as to whether there is a binocular advantage or disadvantage when reading with central vision loss. This study examined binocular reading summation in patients with macular degeneration.
Seventy-one patients with bilateral central vision loss [mean age: 63 (S.D. = 21) years] participated. Reading performances during binocular and monocular viewing with the better eye (i.e., the eye with the best monocular visual acuity) were evaluated using different versions of the Italian MNREAD reading chart (www.precision-vision.com). Fixation stability and preferred retinal loci (PRLs) were recorded monocularly for each eye. The overall sample was split into inhibition, equality, and summation groups based on the binocular ratio (i.e., binocular/monocular) of the maximum reading speed.
41% of patients experienced binocular inhibition, 42% summation, and 17% equality. Binocular reading speed of the inhibition group was approximately 30 words per minute slower than those of the equality and summation groups, although the inhibition group had the best visual acuity. These patients generally had monocular PRLs in non-corresponding locations temporal or nasal to the scotoma, had the largest interocular acuity difference and lacked residual stereopsis. The three groups did not differ in fixational control, contrast sensitivity or critical print size.
Equal proportions of patients with central vision loss show binocular reading summation and inhibition. Patients with binocular reading inhibition have poorer reading performance and different clinical characteristics than those with binocular reading summation and equality.
关于在中心视力丧失时阅读是否存在双眼优势或劣势，存在相互矛盾的报告。本研究检查了黄斑变性患者的双眼阅读总和。
71 名双侧中心视力丧失的患者参与了研究（平均年龄：63 岁，标准差=21 岁）。使用不同版本的意大利 MNREAD 阅读图表（www.precision-vision.com）评估双眼和单眼（即最佳单眼视力的眼睛）注视时的阅读表现。为每只眼睛的注视稳定性和最佳视网膜位置（PRL）进行了单眼记录。根据最大阅读速度的双眼比值（即双眼/单眼），将整个样本分为抑制、相等和总和组。
41%的患者出现双眼抑制，42%出现总和，17%出现相等。抑制组的双眼阅读速度比相等组和总和组慢约 30 个单词/分钟，尽管抑制组的视力最好。这些患者的单眼 PRL 通常位于病变的非对应位置（颞侧或鼻侧），双眼视力差异最大，且缺乏残余立体视。三组在固视控制、对比敏感度或临界印刷尺寸方面没有差异。
中心视力丧失的患者中，相等比例的患者表现出双眼阅读总和和抑制。与双眼阅读总和和相等的患者相比，双眼阅读抑制的患者阅读表现更差，且具有不同的临床特征。
