目的：以首次发作急性闭角型青光眼的对侧眼为研究对象，采用Pentacam眼前节分析系统观察预防性激光虹膜周边切除(laser peripheral iridotomy，LPI)前后眼前节结构变化，评估LPI的有效性和安全性。

方法：急性原发性闭角型青光眼50例50眼的对侧眼行氩激光联合Nd：YAG激光预防性激光周边虹膜切除，检查治疗前及治疗后1d； 6mo的眼内压(intraocular pressure，IOP)，以Pentacam测量中央角膜厚度(central corneal thickness，CCT)、中央前房深度(central anterior chamber depth，CACD)、周边前房深度(peripheral anterior chamber depth，PACD)、前房容积(anterior chamber volume，ACV)、前房角(anterior chamber angle，ACA)、瞳孔直径(pupil diameter，PD)、晶状体厚度(lens thickness，LT)，IOL-Master测量眼轴长度(axial length，AL)，并估算晶状体在眼内的相对位置(relative position of the lens，RPL)。

结果：Pentacam 图像清晰显示凸出的虹膜变平坦，前房角加深。治疗前与治疗后1d； 6mo的眼压无显著变化。CCT值分别为548.02 ±20.22，549.32±21.78，551. 34±26.37mm。CACD值分别为1.65±0.28，1.72±0.31，1.71±0.23mm。PD值分别为2.32±0.55，2.20±0.39，2.38±0.40mm。LT值分别为1.90±0.55，1.82±0.39，1.98±0.40mm。眼AL分别为23.08±1.05，22.91±1.12，22.94±0.96。RPL值分别为0.118±0.035，0.126±0.041，0.121±0.028。治疗前后均无统计学差异。PACD值分别为颞侧(0.88±0.31，1.19±0.25，1.17±0.30mm)，上方(0.83±0.32，1.01±0.42，1.02±0.36mm)，鼻侧(0.80±0.42，0.95±0.21，0.94±0.24mm)，下方(0.83 ±0.34，1.13 ± 0.14，1.12± 0.25mm)； ACV值分别为57.06±18.43，80.65±20.02， 81.43 ±17.21mm³； ACA值分别为27.02° ±6.65°，30.41°±5.87°，31.52°±6.98°，治疗前与治疗后均有统计学差异，治疗后1d与6mo无统计学差异。

结论：LPI能明显增加急性闭角型青光眼对侧眼的周边前房深度和前房容积。Pentacam眼前节分析系统能直观定量反映LPI对于急性闭角型青光眼对侧眼的眼前节三维结构变化。

AIM: To investigate the 3D morphology changes of anterior segment in the fellow eye of acute primary angle closure glaucoma(PACG)before and after neodymium: yttrium aluminum garnet(Nd: YAG)laser periphery iridotomy(LPI)by using Pentacam system and evaluate the safety and efficiency of LPI.

METHODS: Fifty patients(50 eyes)with PACG were enrolled in the study. Before and 1 day, 6 months after LPI, comparison of intraocular pressure(IOP)was measured, comparison of anterior segment parameters such as central corneal thickness(CCT), central anterior chamber depth(CACD), peripheral anterior chamber depth(PACD), anterior chamber volume(ACV), anterior chamber angle(ACA), lens thickness(LT)and pupil diameter(PD)were analyzed by the Pentacam system. The axial length(AL)of eye was measured by IOL-Master, and then comparison of relative position of the lens(RPL)was estimated.

RESULTS: There were no differences among the IOP before and 1 day, 6 months after LPI. The Pentacam system clearly showed the convex configuration of the iris was flattened and the peripheral AC depth was deepened after LPI. Before and 1 day, 6 months after LPI, no statistic changes of CCT were found(548.02 ±20.22mm, 549.32±21.78mm, 551.34±26.37mm, respectively); no statistic changes of CACD were found(1.65±0.28mm, 1.72±0.31mm, 1.71±0.23mm, respectively); no statistic changes of PD were found(2.32±0.55mm, 2.20±0.39mm, 2.38±0.40mm, respectively); no statistic changes of LT were found(1.90±0.55mm, 1.82±0.39mm, 1.98±0.40mm, respectively); no statistic changes of AL were found(23.08±1.05mm, 22.91±1.12mm, 22.94±0.96mm, respectively); no statistic changes of RPL were found(0.118±0.035, 0.126±0.041, 0.121±0.028, respectively). PACD was deepened, temporal from 0.88±0.31mm to 1.19±0.25mm(1 day), 1.17±0.30mm(6 months), superior(0.83±0.32mm, 1.01±0.42mm, 1.02±0.36mm), nasal(0.80±0.42mm, 0.95±0.21mm, 0.94±0.24mm), inferior(0.83±0.34mm, 1.13±0.14mm, 1.12±0.25mm); ACV was increased from 57.06±18.43mm³ to 80.65±20.02mm³(1 day), 81.43±17.21mm 3(6 months); ACA was widened from 27.02°±6.65° to 30.41°±5.87°(1 day), 31.52°±6.98°(6 months), which were increased significantly between before and after LPI, and no difference between 1 day and 6 months after LPI.

CONCLUSION:LPI can induce dramatic changes of 3-D anterior segment morphology in the fellow eye of acute primary angle closure glaucoma(PACG). The changes of AC after LPI can be demonstrated by Pentacam qualitatively and quantitatively.