To evaluate the change of iris-trabecular contact index (ITC index) after cataract surgery in acute angle closure glaucoma.

Twelve patients (17 eyes) who had a history of acute angle closure glaucoma underwent swept source optical coherence tomography before and after cataract surgery. Correlations between lens vault (LV), ITC index and intraocular pressure (IOP), anterior chamber depth (ACD), anterior chamber volume (ACV), and angle parameters were analyzed before and after cataract surgery.

IOP ( p = 0.007), ACD ( p < 0.001), ACV ( p < 0.001), angle parameters ( p = 0.001), and ITC index ( p = 0.012) were improved after cataract surgery. ITC index decreased from 88.42 ± 23.59% to 48.91 ± 35.13% after cataract surgery ( p = 0.012). There was no correlation between LV and ACD ( p = 0.075), ACV ( p = 0.864), angle parameter ( p = 0.112-0.707), or ITC index ( p = 0.288) before cataract surgery. The correlations between ITC index and IOP ( p = 0.021), ACD ( p = 0.002), ACV ( p < 0.001), and angle parameter ( p = 0.001-0.030) were statistically significant before surgery but not statistically significant ( p = 0.223/0.206/0.761/ 0.096-0.819) after surgery.

ITC index significantly improved after cataract surgery, but part of angle closure was not resolved in some cases of acute angle closure glaucoma.