摘要目的:探讨间歇性外斜视(IXT)侧方非共同性(LI)的临床特征和手术矫正效果.方法:回顾性系列病例研究.收集2016年3月至2017年3月在天津市眼科医院收治的并且由同一名医师完成全部评估检查的IXT患者,选择其中具有LI阳性(LI+)(以三棱镜加交替遮盖法测量术前术后原在位、水平左侧、水平右侧的斜视度数,以看远侧方与原在位斜视度差值绝对值≥10△定义为LI+).按照术前LI大小分为LI+A组(＜20△)和LI+B组(≥20△).分析斜视度、斜视类型、非共同性的单双侧等分布和特征,以及手术矫正后LI变化.术后随访3～6个月.采用两独立样本t检验,Fisher精确检验进行数据分析.结果:381例IXT患者中LI+32例(占8.4％),基本型IXT29例(91％),集合不足型IXT 3例(9％),未见类似分开过强型和真性分开过强型;单侧LI+24例(75％),双侧8例(25％);LI相对值,即(看远侧方与原在位斜视度差值绝对值/看远原在位斜视度)×100％,24例(75％)小于40％,8例(25％)≥40％;5例术后仍LI+.LI+A组(24例)和LI+B组(8例)间斜视类型构成、单双侧构成、LI相对值构成、术后LI+构成差异无统计学意义.术前LI+B组远、近原在位平均水平斜视度(-55.0△±7.6△,-60.0△±8.9△)均较A组(-38.8△±12.4△,-44.8△±12.6△)大(t=-3.49、-3.16,P＜0.05).A组、B组术前LI相对值分别为29.7％±10.4％,35.0％±7.6％,差异无统计学意义.术后末次随访,全部患者原在位水平斜视度+2△～-8△.结论:伴有LI现象的IXT以基本型为主,单侧LI多见,水平斜视度较大患者LI绝对值亦较大,LI以绝对值定义可能更可靠.术前充分考量LI的影响,并进行合理的手术设计,可使LI转阴,同时避免原在位的眼位过矫.

abstractsObjective:To investigate the clinical characteristics and surgical outcomes of intermittent exotropia (IXT) with lateral incomitance (LI).Methods:This was a retrospective study.Thirty-two patients with IXT andLI were recruited from 381 patients from March 2016 to March 2017.All were evaluated for horizontal deviations in the primary position,left side and right side with the prism and alternative cover test by the same doctor.LI+ was defined as a reduction in deviation at the side gaze of ≥ 10△ compared to the primary position.Thirty-two patients were divided into group A (LI ＜ 20△) and group B (LI ≥ 20△).The deviation,IXT type,laterality and postoperative LI change were compared and analyzed between the two groups.Patients were followed up for 3 to 6 months.Two independent sample t test and Fisher accurate test were used for statistical analysis.Results:Of 381 patients,32(8.4％) had LI before surgery.Twenty-nine patients (91％) had basic type IXT,3(9％) had convergence insufficiency type IXT and none had pseudo-or truedivergence excess.24(75％) had unilateral LI and 8(25％) had bilateral LI.The relative values of LI,which were equal to (absolute amounts of LI/deviations at distance in the primary position)× 100％,were less than 40％ in 24(75％) and ≥40％ in 8(25％) patients,but postoperative LI were presented in 5 patients.There were no significant differences in compositions of the IXT type,laterality,relative value of preoperative LI or postoperative LI between the two groups.The average horizontal deviations in the primary position at distance and near in group B (-55.0△ ± 7.6△,-60.0△ ± 8.9△,respectively) were greater than the deviations in group A (-38.8△ ± 12.4△,-44.8△± 12.6△,respectively) (t=-3.49,-3.16,P＜ 0.05).However,there was no difference in the relative value of LI between the two groups (29.7％± 10.4％,35.0％±7.6％,respectively.After surgeries,the horizontal deviation in the primary position ranged +2△ to-8△ in all patients.Conclusions:The basic type and unilateral LI are common in IXT with LI.The absolute amount of LI maybe higher in IXT with a greater deviation.We consider LI defined by the absolute amounts may be more reliable.Consideration of the side effects of LI on surgery,an optimal surgical plan could make LI negative and avoid overcorrection in the primary position.