[The correlative factors of darkroom provocative test in anterior segment parameters]

To investigate the correlative anterior segment parameters of positive darkroom provocative test in patients with narrow anterior chamber angles.

It was a retrospective case series study. Two hundred and sixty patients [36 males and 224 females, mean age (59.6 ± 9.3) years] with narrow anterior chamber angles underwent darkroom provocative test and UBM scan were analyzed retrospectively. Anterior segment parameters including anterior chamber depth (ACD), pupil diameter (PD), lens vault (LV), peripheral iris thickness (IT), iris convex (IC), anterior chamber angle open distance (AOD), trabecular-meshwork ciliary process angle (TCPA) and the number of appositional angle closure (NPAC) were quantitatively analyzed. Correlative factors of positive results were analysis by both single factor and multiple-factor analysis.

Seventy-one (27.3%) of the 260 patients had positive results in the darkroom provocative test. Males (15 out of 36) had statistically higher positive result rate than females (56 out of 224) (M: 41.7% vs. F:25.0%, χ(2) = 4.340, P = 0.037). In single factor analysis, male (OR = 2.14), AOD (OR = 0.98), IT (OR = 1.68) and NPAC (OR = 2.24) were correlative factors for positive results. In multiple-factor analysis, only IT (OR = 1.47) and NPAC (OR = 1.70) were independent risk factors of positive results.

Positive darkroom provocative test is correlated to parameters of anterior chamber angle and iris, while IT and NPAC are independent correlative factors in patients with narrow anterior chamber angle.