方法：回顾性分析137例已行斜视手术的间歇性外斜视和恒定性外斜视患者并分为3组。组1：74例间歇性外斜视； 组2：38例有间歇期的恒定性外斜视； 组3：25例无间歇期的恒定性外斜视。分析比较3组患者术后残余斜视度及立体视恢复情况。平均随访2.2a。

结果：组1、组2、组3的眼位矫正成功率分别为78%、68%、64%(组1 vs 组2，P=0.249； 组1 vs 组3，P=0.153； 组2 vs 组3，P=0.716)。组1、组2、组3术后获得双眼视者分别有57例(77%)、5例(13%)、1例(4%)(组1 vs 组2，P<0.001； 组1 vs 组3，P<0.001； 组2 vs 组3，P=0.440)。组1、组2、组3分别有66(89%)、27(71%)、8(32%)例获得粗糙立体视(组1 vs 组2，P=0.015； 组1 vs 组3，P<0.001； 组2 vs 组3，P=0.002)。获得远立体视者组1、组2、组3分别有29例(56%)、5例(24%)、1例(7%)(组1 vs 组2，P=0.013； 组1 vs 组3，P=0.001； 组2 vs 组3，P=0.366)。

结论：曾有间歇期的恒定性外斜视患者术后远期粗糙立体视的恢复优于无间歇期的恒定性外斜视，与间歇性外斜视相比，双眼视、粗糙立体视和远立体视的恢复均较差。有间歇期的恒定性外斜视可能错失了最佳治疗时机，早期手术可优化术后感觉功能结果。

METHODS: Totally 137 patients with intermittent exotropia or constant exotropia who had underwent surgery were analyzed retrospectively. They were assigned into three groups: group 1, seventy-four patients with X(T); group 2, thirty-eight constant exotropia patients with a previously intermittent history; group 3, twenty-five constant exotropia patients without a previously intermittent history. The surgical outcomes in the ocular deviation and the recovery of stereoacuity were compared separately among the three groups. The average follow-up time was 2.2 years.

RESULTS: The successful alignment rates were 78%(group 1), 68%(group 2), 64%(group 3), respectively(group 1 vs group 2, P=0.249; group 1 vs group 3, P=0.153; group 2 vs group 3, P=0.716). Fifty-seven patients(77%)in group 1, five patients(13%)in group 2 and one patient(4%)in group 3 achieved binocularity after surgery(group 1 vs group 2, P<0.001; group 1 vs group 3, P<0.001; group 2 vs group 3, P=0.440). The number of patients who achieved gross stereopsis in group 1, group 2 and group 3 were 66(89%), 27(71%), 8(32%)(group 1 vs group 2, P=0.015; group 1 vs group 3, P<0.001; group 2 vs group 3, P=0.002). Twenty-nine patients(56%)in group 1, 5 patients(24%)in group 2, 1 patients(7%)in group 3 achieved distance stereoacuity(group 1 vs group 2, P=0.013; group 1 vs group 3, P=0.001; group 2 vs group 3, P=0.366).

CONCLUSION: Patients with constant exotropia who had a intermittent history have a better surgical result compared with those without a intermittence period in gross stereopsis, but a worse postoperative sensory outcome than patients with X(T)in binocular vision, gross stereopsis, and distant stereoacuity. Constant exotropia patients with a period of X(T)may have missed the optimal timing for treatment, early surgery can optimize the postoperative sensory results.