Comparative analysis of intraocular pressure dynamics after phacoemulsification with intraocular lens implantation in eyes with primary glaucoma
Authors: Kolesnikov A. V. , Ban E. V. , Kolesnikova M. A. , Mironenko L. V. , Prozorova A. I. , Sevostyanov A. E. 
Published: December 2021

PURPOSE. To conduct a comparative analysis of changes in intraocular pressure (IOP) after cataract phacoemulsification with implantation of intraocular lens (IOL) in comorbidity with primary open-angle (POAG) and primary closed-angle glaucoma (PACG).

METHODS. The study analyzed the dynamics of IOP changes after cataract phacoemulsification in 65 patients (89 eyes) with comorbid PACG and 46 patients (58 eyes) with comorbid POAG, aged 50 to 92 years. Thirty-five (53.85%) patients with POAG had history of glaucoma surgery, and 12 (20.69%) patients with PACG had been treated with laser iridectomy. The disease was in the initial stage in 14.6% of POAG patients and 5.15% of PACG patients; moderate stage — in 55.05% and 47.19%, respectively; advanced stage — in 30.34% and 24.14%. Intraocular pressure in POAG was compensated in 84.5% and subcompensated in 15.5% of patients; in PACG it was compensated in 77.6%, subcompensated in 12.6%, and uncompensated in 10.4% of patients. Compensation of IOP was achieved either by previous surgeries, or application of local antihypertensive medications. Patients with subcompensated and elevated IOP received the maximum possible amount of hypotensive medications. The follow-up period ranged from 1 month to 2 years.

RESULTS. Patients were divided into three groups according to postoperative IOP levels: the first group with IOP equal to preoperative level, the second group — with IOP below the initial level, and the third group with IOP above the initial level. The IOP levels were consistent with preoperative values at all follow-up periods in most of study patients, and after 2 years their portion exceeded 70%, while in POAG it was somewhat higher than in PACG (77.42% against 71.43%). The IOP below the preoperative level was observed in eyes with initial and moderate open-angle and closed-angle glaucoma, with the amount decreasing with longer follow-up (from 63.16% at 3 months to 16.13% after 2 years in POAG, and from 62.74% to 19.04% in PACG). In the early postoperative period, number of POAG and PACG patients in this group was comparable, but after 8 months it included more PACG patients. Elevation of IOP in both forms of glaucoma was most often observed in faradvanced stage in the early post-op period after phacoemulsification, subsequently their number decreased and by two years it decreased by almost twice (6.45% vs. 11.84% in POAG and 9.53% vs. 15.69% in PACG). During the entire follow-up period, the number of patients with ophthalmic hypertension in PACG was 30% higher than in POAG.

CONCLUSION. The study showed that in most cases phacoemulsification has a stabilizing effect in patients with cataracts in combination with glaucoma. The hypotensive effect of the operation was observed in initial and advanced stages of glaucoma, when the drainage system of the eye was still preserved, and in the long term it was observed in a larger percentage of cases in angle-closure glaucoma compared to open-angle glaucoma. An increase in intraocular pressure relative to the preoperative level was observed in advanced glaucoma throughout the entire follow-up period, and the number of patients with angleclosure glaucoma was one-third higher than the number of patients with open-angle glaucoma. The obtained ambiguous results of intraocular pressure measurements after phacoemulsification of cataract with implantation of IOL in combination with various forms of glaucoma dictate the need for further study of this problem.