Department of Ophthalmology, University of Heidelberg, Heidelberg, Germany.
Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany.
Graefes Arch Clin Exp Ophthalmol. 2020 Jun;258(6):1319-1326. doi: 10.1007/s00417-020-04690-z. Epub 2020 Apr 29.
Potential sources of error in dosage planning in strabismus surgery are (a) prismatic side-effects of spectacle lenses when measuring the preoperative angle with the alternating prism cover test and (b) a potential influence of eye ball axial length on dose response. As both errors take effect in opposite directions, many strabismus surgeons set aside their consideration. This study investigates whether considering both factors for dosage planning yields better operative results.
In this prospective, randomised, double-blind, interventional pilot study, we included patients scheduled for purely horizontal strabismus surgery and determined each patient's surgical dose (total amount of recession/plication) either with (study group) or without (control) consideration of the two factors. The deviation of the resulting angle from the target angle 3 months postoperatively was the primary endpoint.
One hundred one patients were included, 51 of which in the intervention group and 50 in the control group. The primary endpoint showed a median deviation from the target of 3.0° in the intervention group and 4.8° in the control group. We observed a group difference of 1.8° in favour of the intervention group (p = 0.053). Subgroup analysis showed a difference between groups of 2.2° for esotropic patients and of 5.1° for patients with hyperopia > + 2 D.
Taking prismatic side-effects of spectacle lenses and eye ball length into account when calculating strabismus surgery doses showed a trend towards more accurate results. Esotropic patients and patients with hyperopia > + 2 D seemed to benefit most.
International Clinical Trials Registry Platform: DRKS00011121.
斜视手术中剂量规划的潜在误差源为：(a) 用交替棱镜遮盖试验测量术前角度时，眼镜的棱镜副作用；(b) 眼球轴向长度对视轴反应的潜在影响。由于这两个误差的作用方向相反，许多斜视外科医生忽略了这两个因素。本研究旨在探讨在剂量规划中同时考虑这两个因素是否能获得更好的手术效果。
这是一项前瞻性、随机、双盲、干预性的初步研究，纳入了拟行单纯水平斜视手术的患者，通过考虑（研究组）或不考虑（对照组）这两个因素来确定每位患者的手术剂量（总转位量/总缩短量）。术后 3 个月，实际角度与目标角度的偏差为主要终点。
共纳入 101 例患者，其中 51 例纳入干预组，50 例纳入对照组。主要终点显示，干预组的实际角度与目标角度的中位数偏差为 3.0°，对照组为 4.8°。我们观察到干预组的偏差为 1.8°，这有利于干预组（p=0.053）。亚组分析显示，对于内斜视患者，组间差异为 2.2°，对于远视> +2 D 的患者，组间差异为 5.1°。
在计算斜视手术剂量时，考虑眼镜的棱镜副作用和眼球长度对视轴反应的影响，显示出更准确的结果的趋势。内斜视患者和远视> +2 D 的患者获益最大。
国际临床试验注册平台：DRKS00011121。
