Analysis of the refraction error and the influencing factors after phacoemulsification in acute primary angle-closure glaucoma with cataract

Abstract

AIM: To compare the refraction error(RE)3mo after phacoemulsification combined with intraocular lens implantation(PHACO+IOL)between patients with acute primary angle-closure glaucoma(APACG)with cataract(APACG group)and patients with simple cataract(cataract group), and the biological parameters of the eye(axial length,corneal curvature, anterior chamber depth)associated with the postoperative RE in the APACG and cataract groups. METHODS: This was a prospective, non-randomized, case-control study. Each group had 30 cases(30 eyes). Intraocular pressure, axial length, corneal curvature, and anterior chamber depth were measured. The reserved refractive power was calculated using the SRK-II formula. Three months postoperatively, subjective RE was calculated as the postoperative refractive power which subtracted the preoperative reserved diopter(RE was considered as +0.50D; -0.50D to +0.50D not considered as RE). An independent sample t-test was used to compare the difference in RE between the two groups and to compare the differences among relevant parameters such as axial length, corneal curvature, and anterior chamber depth. Paired t-test was used to compare preoperative and postoperative parameters such as axial length, corneal curvature, and difference in anterior chamber depth. RESULTS: Mean RE in the cataract group was -0.46D±0.46D, with 24 cases of myopic RE(80%)and 6 cases of hyperopic RE(20%). Mean RE in the APACG group was +0.56D±0.79D, with 9 cases of myopic RE(30%)and 21 cases of hyperopic RE(70%). The difference in RE between the two groups was statistically significant(PP>0.05). In the APACG group, pre- and postoperative axial length was 21.71±0.46mm and 21.52±0.54mm, respectively; the difference was statistically significant(PPP>0.05). On comparison of biological parameters between the two groups, postoperative ocular axial length shortening in the APACG group was statistically significant compared with the ocular axial changes in the cataract group(PPCONCLUSION:Postoperative RE in patients with APACG and cataract who underwent PHACO+IOL is relatively large compared with patients with simple cataracts. These patients with APACG and cataract also show hyperopia drift, which is more significantly correlated with postoperative ocular axial length shortening and increased anterior chamber depth.

Keywords

• primary angle closure glaucoma
• refractive error
• phacoemulsification
• phacoemulsification