改良黏小管切开术后眼前段相干光断层成像的观察及其眼压下降机制的临床研究

AS-OCT revealed mechanisms of aqueous humour drainage after modified viscocanalostomy in open-angle glaucoma

目的应用眼前段相干光断层成像（AS-OCT）检测改良黏小管切开术（VCO）术后手术区域组织结构及滤道,以讨论改良黏小管切开术降眼压的机制。方法横断面研究。研究对象为术后从3~72个月的38例（55只眼）开角型青光眼,均为术前药物控制不良的开角型青光眼。11只眼（20%）因眼压高行Nd：YAG激光房角穿孔术。同时进行视力、眼压、裂隙灯、眼底和AS-OCT检查。AS-OCT的检测指标为：1滤过泡形态,2巩膜池的长、宽、高,3脉络膜上腔,4泪河高度。结果患者术后眼压（15.4±4.9）mm Hg较术前（31.0±10.9）mm Hg明显下降,42只眼有弥散的滤泡。AS-OCT证明了结膜瓣下腔隙的存在,39只眼（70.9%）检测到巩膜池,巩膜池的平均体积为1.09 mm^3（0.04~0.203 mm^3）。结论 AS-OCT检查证明了改良VCO房水引流的可能机制。扁平弥散的结膜下腔隙证明了持续的滤过,为眼外引流;39只眼（70.9%）存在巩膜池。巩膜池的体积与眼压无关,提示脉络膜上腔可能是主要的房水眼内引流途径。

Objective The aim of this study was to reveal structural and mechanical changes of outflow pathways after modified viscocanalostomy（ modified VCO） using anterior segment optical coherence tomography（ AS-OCT）. Methods Fifty-five eyes of 38 patients with medically uncontrolled open-angle glaucoma received modified VCO. Eleven eyes（20%） also received Nd：YAG laser goniopuncture to further control intraocular pressure（ IOP）. Postoperative follow-up included complete ophthalmic examinations and AS-OCT scan of the filtering site. The following assessments were done with AS-OCT： 1） dimensions of subconjunctival filtering bleb; 2） volume of intrascleral cavity; 3） volume of suprachoroidal space; 4） height of tear meniscus. Results Intraocular pressure decreased significantly from 31. 0 ± 10. 9 mmHg to 15. 4± 4. 9mmHg. AS-OCT demonstrated a subconjunctival space in forty-two eyes. In 39 eyes（ 70. 9%） an intrascleral cavity was observed. The mean volume of this cavity was 1. 09 mm^3（0.04-0.203 mm^3）. Conclusion AS-OCT revealed several possible pathways for aqueous humour drainage after modified VCO. A flat,diffuse subconjunctival space indicated persistent drainage. Thirty-nine eyes（ 70. 9%） exhibited a remaining intrascleral cavity,whose volume was unrelated to IOP,suggesting that suprachoroidal outflow may be the main outflow pathway after modified VCO.