Fletcher Donald C, Schuchard Ronald A, Renninger Laura W
Department of Ophthalmology, California Pacific Medical Center, San Francisco, California, USA.
Optom Vis Sci. 2012 Sep;89(9):1395-8. doi: 10.1097/OPX.0b013e318264cc77.
To assess whether age-related macular degeneration (AMD) patients are aware of binocular central visual field defects.
One hundred fifty-three consecutive AMD patients in their initial low-vision rehabilitation evaluation were immediately asked at the beginning of their visit (1) whether they were able to see any blind spots or defects in their field of vision and (2) whether they had any evidence or experiences that led them to believe that they had defects in their field of vision. They then had their vision assessed by binocular central visual field testing using the California Central Visual Field Test, binocular reading performance evaluated using the Smith-Kettlewell Reading Test (SK Read) and MN Read charts, and visual acuity measured using the ETDRS chart at 1 meter. Mean diameters of the scotomas with borders near fixation were noted.
Visual acuity median was 20/253 (range 20/40 to hand movements). Binocular scotomas were present in 88% of patients (66% had dense scotoma). Of patients with binocular scotomas, 56% were totally unaware of their presence, even with dense scotomas measuring up to 30° in diameter; 1.5% could fleetingly see a defect in their visual field on waking; and 44% related experiences of things "disappearing" on them. The median and range of scotoma diameters for those unaware vs. those with some awareness of their scotomas were comparable. There was no significant relationship of awareness of the scotoma with age, acuity, scotoma size, density, or duration of onset. Awareness of scotoma was associated with fewer errors on the SK Read (p < 0.01).
Low vision clinicians cannot depend on patients to report the presence of significant scotomas; thus, appropriate testing must be performed. Presence of scotomas decreased reading accuracy, but some awareness of the scotomas had a tendency to improve accuracy. The value of rehabilitation programs aimed at increasing patient awareness of their scotomas may be supported by this evidence.
评估年龄相关性黄斑变性（AMD）患者是否知晓双眼中心视野缺损。
153例初次接受低视力康复评估的连续性AMD患者在就诊开始时即刻被询问：（1）他们是否能看到视野中的任何盲点或缺损；（2）他们是否有任何证据或经历使其相信自己视野存在缺损。然后使用加利福尼亚中心视野测试进行双眼中心视野检测来评估其视力，使用史密斯 - 凯特尔韦尔阅读测试（SK阅读）和MN阅读图表评估双眼阅读表现，并使用ETDRS图表在1米处测量视力。记录靠近注视点边界的暗点平均直径。
视力中位数为20/253（范围为20/40至手动）。88%的患者存在双眼暗点（66%有密集暗点）。在有双眼暗点的患者中，56%完全未意识到其存在，即便暗点直径达30°；1.5%在醒来时能短暂看到视野中有缺损；44%有东西在他们视野中“消失”的相关经历。未意识到暗点的患者与意识到暗点的患者的暗点直径中位数及范围相当。暗点的知晓情况与年龄、视力、暗点大小、密度或发病持续时间无显著关系。暗点的知晓情况与SK阅读中较少的错误相关（p < 0.01）。
低视力临床医生不能依赖患者报告显著暗点的存在；因此，必须进行适当检测。暗点的存在降低了阅读准确性，但对暗点的一些知晓有提高准确性的趋势。旨在提高患者对其暗点知晓度的康复项目的价值可能得到这一证据的支持。
