Changes in Iridotrabecular Contact and Intraocular Pressure after Phacoemulsification in Primary Angle-Closure Disease Spectrum.

PURPOSE: To compare changes in the swept-source (SS) anterior-segment optical coherence tomography (AS-OCT) parameters and intraocular pressure (IOP) control after lens extraction in various spectra of primary angle-closure disease (PACD).

METHODS

A total 92 eyes from 92 patients with PACD who underwent lens extraction were included in the study. All patients underwent IOP measurement preoperatively and at 1 day, 1 week, and 1, 3, and 6 months postoperatively. SS AS-OCT was performed in all subjects preoperatively and 1 month postoperatively. All participants were divided into two groups depending on the presence of glaucomatous optic disc or visual field damage (group A, PAC suspect or PAC; group B, PAC glaucoma). The changes in IOP and anterior chamber angle parameters of SS AS-OCT of each group were compared. Regression analysis was performed to find factors associated with the degree of IOP reduction after lens extraction.

RESULTS

Preoperatively, there was no significant difference in IOP between the two groups (16.3 ± 2.5 mmHg vs. 16.9 ± 3.2 mmHg, p = 0.297), but the number of glaucoma medications used was greater in group B (0.6 ± 1.0 vs. 2.0 ± 0.9, p < 0.001). Postoperatively, IOP was not significantly different, but the number of medications used was greater in group B (0.2 ± 0.7 vs. 0.9 ± 0.8, p < 0.001). Anterior chamber angle parameters including angle opening distance and trabecular-iris angle had a greater increase in group B after lens extraction. However, the residual iridotrabecular contact (ITC) index was significantly greater in group B (5.6 ± 7.0 vs 10.7 ± 12.1, p = 0.014). A greater change in the ITC index was related to a greater degree of IOP reduction (β coefficient, 0.429; p < 0.001).

CONCLUSIONS

Eyes with PAC glaucoma had a greater residual ITC index after lens extraction compared with eyes of other PACD spectrum and required a greater number of glaucoma medications to maintain a similar level of IOP.