Clinical observation of 3 minutes dark-room provocative test in patients with laser peripheral iridectomy in the fellow eyes of acute angle-closure glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

ABSTRACT

AIM:To observe related biological parameters of 3 minutes dark-room provocative test in patients with laser peripheral iridectomy(LPI) in the fellow eyes of acute primary angle-closure (APAC) by ultrasound biomicroscopy (UBM).To explore the risk factors in primary angle closure suspect(PACS) patients with progressive angle closure after LPI.METHODS: Seventy-eight eyes of APAC patients without peripheral anterior synechia were selected.Each eye underwent 3 minutes dark-room provocative test after LPI.Anterior segment parameters, including anterior chamber depth (ACD), anterior chamber angle open distance500 (AOD500), peripheral iris thickness (PIT), iris convex (IC), the position of iris insertion and trabecular-ciliary process distance (TCPD), and the number of positional angle closure(NPAC) were observed and analyzed by statistic methods.RESULTS:Patients with APAC were examined by UBM after LPI and 26 eyes(33%) occurs at least one positional angle closure,19 eyes(24%)were positive in 3 minutes dark-room provocative test among them.It occurs a positive relationship between the elevation intraocular pressure and the number of positional angle closure in dark-room provocative test(r=0.84, P<0.01).AOD500, IT and IC were significantly changed from normal light to darkroom between positional angle closure positive group and positional angle closure negative group(all P<0.01).In single factor analysis, AOD500(P=0.003), IT(P=0.012), IC(P=0.043), TPCD(P=0.015), the position of iris insertion(P=0.024) were correlative factors of positive results.In multiple-factor analysis, only IT(P=0.011), TPCD(P=0.009), iris root attachment points(P=0.02) were independent risk factors of positive results.CONCLUSION:A certain proportion of patients with PACS after LPI appeared positional angle closure in a dark room.Peripheral iris hypertrophy, anterior displacement of the ciliary body and iris root attachment points are vital risk factors.Long-term follow-up study and intervention treatment are required in these patients after LPI.