Low Vision Service, University Health Network Hospitals, Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.
University of Western Ontario, London, Ontario, Canada.
J Optom. 2021 Oct-Dec;14(4):342-345. doi: 10.1016/j.optom.2020.10.004. Epub 2021 Jan 19.
To determine the efficacy of prisms when used for redirection of incoming images towards the preferred reinal loci (PRLs) for restitution of potential visual acuity (PVA) in low vision cases with age-related macular degeneration (AMD).
Retrospective comparative interventional case series review. Low vision rehabilitation (LVR) protocol used included best corrected visual acuity (BCVA), PVA, topographic PRL identification and use of prisms to produce image redirection to the presumed PRL. The primary outcome measure selected for analysis was BCVA for viewing distance targets after use of yoke prisms.
Image relocation with prisms in patients with AMD resulted in significantly better BCVA levels (t = 8.57, p < 0.0001) in the better eye. Distance BCVA levels achieved were almost identical to PVA levels (t = 0.415, p < 0.681) (y= -0.136 + 1.195x, r = 0.8333, p < 0.001).
Use of yoke prisms for image redirection towards a peripheral identifiable PRL may result in PVA restitution in most cases.
确定棱镜在用于将传入图像重新引导至与年龄相关性黄斑变性 (AMD) 低视力患者的潜在视敏度 (PVA) 恢复相关的首选视网膜部位 (PRL) 时的效果。
回顾性对比干预性病例系列研究。低视力康复 (LVR) 方案包括最佳矫正视力 (BCVA)、PVA、PRL 的地形定位以及使用棱镜将图像重定向到假定的 PRL。选择用于分析的主要结果测量指标是使用轭式棱镜后观察距离目标的 BCVA。
AMD 患者使用棱镜进行图像重新定位，可显著提高较好眼的 BCVA 水平（t=8.57，p<0.0001）。所达到的距离 BCVA 水平几乎与 PVA 水平相同（t=0.415，p<0.681）（y=-0.136+1.195x，r=0.8333，p<0.001）。
在大多数情况下，使用轭式棱镜将图像重新引导至可识别的周边 PRL 可能会导致 PVA 恢复。
