Department of Ophthalmology, Jeonbuk National University Hospital, Jeonju, Republic of Korea.
Department of Ophthalmology, Jeonbuk National University College of Medicine, Jeonju, Republic of Korea.
Graefes Arch Clin Exp Ophthalmol. 2022 Jan;260(1):345-352. doi: 10.1007/s00417-021-05338-2. Epub 2021 Aug 18.
Monofixation syndrome (MFS) is a specific subnormal binocular vision status, either with or without a small deviation. Patients with MFS have a tendency to maintain stable ocular alignment. Correction of refractive errors and occlusion are considered as treatment option for amblyopia, and the status of MFS could be changed with long-term follow-up. The purpose of this study is to evaluate whether a Fresnel prism affected the visual acuity, angle of deviation, and sensory status in small-angle esotropia with subnormal stereopsis presenting with MFS features.
Patients with small-angle esotropia within 8 prism diopters (PD) on the simultaneous prism and cover test from 2010 to 2019 were reviewed. Patients with subnormal stereopsis defined as more than 100 s of arc (arcsec) and with the central suppression with peripheral fusion were only included. A Fresnel prism was applied to the dominant eye, and the minimum follow-up period after Fresnel prism treatment was 24 months. We assessed patient clinical characteristics, course and response to therapy including visual acuity, angle of deviation, and stereopsis.
Twenty patients with a mean age of 5.5 ± 1.4 years were included. The mean duration of Fresnel prism treatment was 15.3 ± 10.3 months. After 50.7 ± 17.2 months of follow-up, VA of the non-dominant eye was changed from 0.26 ± 0.20 logMAR to 0.07 ± 0.17 logMAR (P < .001). The initial stereoacuities were 3.54 ± 0.27 log arcsec, ranged from 6000 to 400 arcsec. After the treatment with Fresnel prism, the final stereoacuities were 3.09 ± 0.58 log arcsec, ranged from 6000 to 100 arcsec (P = .001); nine patients (45%) improved stereoacuity more than two octaves. No changes in the angle of deviation or a change of fixation were observed.
After use of Fresnel prism, there was some improvement in visual acuity and stereopsis in patients with MFS features. Following occlusion and refractive correction, management using Fresnel prism could be attempted in small-angle esotropic patients with amblyopia or subnormal stereopsis.
单眼固视综合征（MFS）是一种特定的非正常双眼视觉状态，可能伴有或不伴有小斜视。MFS 患者往往有维持稳定眼位的趋势。屈光不正的矫正和遮盖治疗被认为是弱视的治疗选择，MFS 的状态可以随着长期随访而改变。本研究旨在评估在伴有 MFS 特征的小角度内斜视中，使用 Fresnel 棱镜是否会影响小角度斜视患者的视力、斜视角度和感觉状态，这些患者的立体视锐度低于正常。
回顾 2010 年至 2019 年间，在同时使用棱镜和遮盖试验中，斜视角度在 8 棱镜屈光度（PD）以内的小角度内斜视患者。仅纳入立体视锐度低于正常（超过 100 弧秒）且伴有中心抑制伴周边融合的患者。在优势眼上应用 Fresnel 棱镜，并且 Fresnel 棱镜治疗后的最小随访时间为 24 个月。我们评估了患者的临床特征、病程和治疗反应，包括视力、斜视角度和立体视锐度。
共纳入 20 例平均年龄为 5.5±1.4 岁的患者。Fresnel 棱镜治疗的平均时间为 15.3±10.3 个月。随访 50.7±17.2 个月后，非优势眼的视力从 0.26±0.20 logMAR 变为 0.07±0.17 logMAR（P<.001）。初始立体视锐度为 3.54±0.27 log 弧秒，范围为 6000 至 400 弧秒。使用 Fresnel 棱镜治疗后，最终立体视锐度为 3.09±0.58 log 弧秒，范围为 6000 至 100 弧秒（P=.001）；9 名患者（45%）的立体视锐度提高了两个以上的倍频程。未观察到斜视角度的变化或固视点的改变。
在使用 Fresnel 棱镜后，MFS 特征患者的视力和立体视锐度均有一定程度的提高。在遮盖和屈光矫正之后，可以尝试在伴有弱视或立体视锐度低于正常的小角度内斜视患者中使用 Fresnel 棱镜进行治疗。
