预防性激光周边虹膜切除术对不同房角关闭机制原发性闭角型青光眼的疗效

目的：应用超声生物显微镜（UBM）评价原发性闭角型青光眼（PACG）患者行预防性激光虹膜周切术（LPI）治疗后不同疗效的机制分析。方法：本研究搜集了2018.03-2021.10在上海长海医院临床检查确诊的原发性闭角型青光眼和行LPI术的共23位病人（5位男性，18位女性），35只眼睛。对所有受试者在LPI治疗前和治疗后一周进行标准眼科临床检查和UBM显像检查，检查包括基线评估（最佳矫正视力、眼压、裂隙灯显微镜联合房角镜检查、眼底照相、自动静态视野计及OCT等检查）及UBM（房角结构：ACD, AOD, TIA, TCPD, ICPD）。根据UBM图像及Svend Vedel Kessing和John Thygesen的分类方法，将房角关闭机制定义为单纯瞳孔阻滞型(PB)、高褶虹膜型(PI)和混合型。结果：在LPI前单纯瞳孔阻滞组（PB）占比达到85.7%，14.3%的患者属于高褶虹膜型(PI)。LPI后，PB组里有51.4%表现为单纯PB，34.2%表现为混合机制(PB和PI)。LPI后，PB型(13.6°±2.4°，p<0.01)和混合型(6.1°±1.7°，p<0.01)的房角开放度明显增加，而PI型(1.6°±0.8°，p>0.05)无明显变化。结论：根据UBM图像分析，单纯瞳孔阻滞型（PB）行LPI后房角开放效果较好，而高褶虹膜型（PI）患者行LPI术后的临床和UBM特征基本不变，显示PI在引起房角关闭的机制及程度上有特殊作用。

Prophylactic laser peripheral iridotomy for primary angle closure glaucoma with different angle closure mechanisms

Objective To evaluate the angle changes in patients with primary angle closure glaucoma (PACG) after prophylactic laser peripheral iridotomy (LPI) using ultrasound biomicroscopy (UBM), and analyze the treatment effect on patients with different angle closure mechanisms. Methods Basic standard examination and UBM were performed before and 1 week after LPI on 23 patients (35 eyes) who were diagnosed with PACG in The First Affiliated Hospital of Naval Medical University (Second Military Medical University) from Mar. 2018 to Oct. 2021. Based on the UBM results, the angle closure mechanisms were divided into pupillary block type, plateau iris type, and mixed type. Results Among the 35 eyes, 30 (85.7%) eyes showed pupillary block type and 5 (14.3%) showed plateau iris type before LPI. After LPI, 18 of the 30 eyes showing pupillary block before LPI showed pupillary block type and 12 showed mixed type, and the degree of angle opening was increased (20.2°±4.2° vs 6.6°±1.8° in reclassified pupillary block type and 12.4°±3.9° vs 6.3°±1.7° in reclassified mixed type, both P<0.05); the 5 eyes showing plateau iris type before LPI had no change in classification or the degree of angle opening (8.3°±1.7° vs 6.7°±2.1°, P>0.05). Conclusion The effect of opening angle after LPI is better in PACG patients with pupillary block type, but not in patients with plateau iris type, suggesting that plateau iris plays an important role in angle closure mechanisms in PACG patients and affects the effect of LPI.