Effect of horizontal rectus surgery for the correction of intermittent exotropia on sub-A or sub-V pattern

We evaluated effect of horizontal rectus surgery on sub-A or sub-V pattern intermittent exotropia. We enrolled patients with sub-A or sub-V pattern intermittent exotropia. The sub-A pattern was diagnosed when the eyes diverged less than 10 prism diopters (PD) from upgaze to downgaze, and sub-V pattern when the divergence was 14 PD or less from downgaze to upgaze. Patients had undergone horizontal rectus surgery without vertical transposition of horizontal rectus muscle or oblique muscle weakening. The patients were divided into two groups: sub-A pattern (group A) and sub-V pattern (group V). The outcome measures were change of amount of pattern and rate of collapse of pattern postoperatively. The amount of pattern (vertical incomitance) was amount of difference in exodeviation between upgaze and downgaze. Collapse of pattern was defined as disappearance of difference in exodeviation between upgaze and downgaze. In groups A and V, preoperative amounts of pattern were 4.9 PD and 6.8 PD, respectively. A significant reduction in amount of pattern was observed in both groups throughout the follow-up period (p本研究评估了水平直肌手术对亚型A（sub-A）或亚型V（sub-V）型间歇性外斜视（intermittent exotropia）的治疗效果。我们纳入了确诊为亚型A型或亚型V型间歇性外斜视的患者。当眼球从向上注视至向下注视时的外斜视度差值小于10棱镜度（PD）时，即可诊断为亚型A型；当眼球从向下注视至向上注视时的外斜视度差值不超过14PD时，则诊断为亚型V型。所有入组患者均接受了水平直肌手术，且未行水平直肌垂直移位术或斜肌减弱术。本研究将患者分为两组：亚型A型组（A组）与亚型V型组（V组）。本研究的主要结局指标为术后斜视亚型的量化变化量与亚型消失率。斜视亚型的量化值（垂直非一致性（vertical incomitance））指向上注视与向下注视时的外斜视度差值。亚型消失被定义为向上注视与向下注视时的外斜视度差值完全消失。A组与V组的术前斜视亚型量化值分别为4.9PD与6.8PD。两组患者在整个随访周期内的斜视亚型量化值均出现显著降低（p