原发性前房角关闭眼在施行激光周边虹膜切除术后前房角关闭的发生率和发病机制的研究

【作者】 杨渊筌；

【导师】 赵家良；

【作者基本信息】 中国协和医科大学 ， 眼科学， 2008， 硕士

【摘要】 目的:了解原发性前房角关闭(primary angle closure,PAC)眼在施行预防性激光周边虹膜切除术(laser peripheral iridotomy,LPI)后前房角关闭的发生率,并通过比较PAC眼施行LPI后前房角关闭较轻者与较重者之间、PAC眼与正常前房深度眼之间的一些前房和前房角结构的参数,探讨PAC眼施行LPI后前房角关闭的可能机制。对象和方法:(1)应用前瞻性干预性系列病例研究。对39名来自北京协和医院眼科门诊就诊的PAC患者施行LPI,并比较术前和术后两周的暗室下超声活体显微镜(ultrasound biomicroscopy,UBM)图像中获得的前房和前房角参数,包括中央前房深度(anterior chamber depth,ACD),附着性前房角关闭(iridotrabecularcontact,ITC)的范围,前房角开放距离(angle opening distance,AOD),小梁网-睫状突距离(trabecular-ciliary process distance,TCPD),周边部虹膜厚度(irisdistance,ID),虹膜-睫状突接触(iris-ciliary process contact,ICPC)的发生率,巩膜突-睫状突距离(sclera spur-ciliary process distance,SSCPD),小梁网-睫状突角(trabecular-ciliary process angle,TCPA)。(2)应用病例对照研究。将上述39只PAC眼,按LPI后前房角关闭的严重程度分为重度组(前房角关闭钟点数＞3钟点位,23眼)和轻度组(前房角关闭钟点数≤3钟点位,16眼)。比较PAC眼LPI后前房角关闭轻度组、重度组和正常前房深度组(20眼)三组之间的UBM前房及前房角参数,包括ACD、ID、TCPD、TCPA和SSCPD。结果:(1)79.49%(31/39)的PAC眼在LPI后前房角有不同程度的增宽。87.18%(34/39)的PAC眼在LPI后暗室下UBM检查仍有≥1个钟点位的附着性前房角关闭。(2)在正常前房深度组、PAC眼LPI后前房角关闭轻度组和重度组之间的比较中,TCPD和TCPA呈递减趋势,组间差异具有统计学意义(P＜0.0001);ACD在正常前房深度组明显大于两组PAC眼(P＜0.0001),但是PAC眼两组之间的差异无统计学意义(P=0.7170);ID和SSCPD在三组间的差异无统计学意义(P＞0.05)。PAC眼LPI后前房角关闭钟点位数与TCPD和TCPA的相关系数分别为-0.4312(P=0.0069)和-0.3958(P=0.0126)。结论:PAC眼LPI后的前房角关闭发生率极高。睫状突前位是导致PAC眼LPI后的前房角关闭的主要原因。更多还原

【Abstract】 Purpose: To evaluate the prevalence of angle closure in eyes with primary angle closure (PAC) after laser peripheral iridotomy (LPI) and to determine the pathogenesis of this condition by comparing the anterior chamber and angle parameters among PAC eyes with severe angle closure after LPI, PAC eyes with mild angle closure after LPI and normal subjects.Participants and Methods: (1) Based on the principle of prospective intervention case series study, prophylactic LPI was performed in 39 patients with PAC in the Department of Ophthalmology at Peking Union Medical College Hospital. Ultrasound biomicroscopy (UBM) examination was carried out before and 2 weeks after LPI in these eyes. One randomly selected eye of each subject was measured. UBM parameters before LPI were compared with those after LPI, including iridotrabecular contact (ITC), iris-ciliary process contact (ICPC), angle opening distance (AOD), trabecular-ciliary process distance (TCPD), iris distance (ID), scleral spur-ciliary process distance (SSCPD) and trabecular-ciliary process angle (TCPA). (2) The PAC eyes mentioned above were classified into two groups according to the severity of angle closure after LPI, severe one ( angle closure range after LPI≥4 clock positions, 23 eyes)and mild one ( angle closure range after LPI≤3 clock positions, 16 eyes). Based on the principle of case control study, UBM parameters of the two PAC groups after LPI were compared with those of the group with normal anterior chamber depth (20 eyes), including ACD, ID, TCPD, TCPA, SSCPD.Results: (1) 79.49% (31/39) PAC eyes had wider angles after LPI. However, the proportion of eyes with UBM-identified ITC in≥1 clock position after LPI was 87.18% (34/39). (2) Among the three groups mentioned above, TCPD and TCPA were significantly smaller in eyes with severe angle closure after LPI compared to those with mild angle closure after LPI as well as the normal ones (P=0.0001). ACD was significantly smaller in eyes with PAC than eyes with normal anterior chamber (P<0.0001), however, there was no significant difference in ACD within PAC eyes. There were no significant differences among the three groups in ID and SSCPD. The correlation coefficient between angle closure range after LPI and TCPD was -0.4312 (P=0.0069) and between angle closure range after LPI and TCPA was -0.3958 (P=0.0126).Conclusions: Angle closure was common in PAC eyes after LPI. Anteriorly positioned ciliary process played a key role in the pathogenesis of angle closure after LPI in PAC eyes.更多还原