Long term outcomes of cataract surgery in severe and end stage primary angle closure glaucoma with controlled IOP: a retrospective study

BACKGROUND: To investigate the long term surgical outcomes of cataract surgery in severe and end stage glaucoma patients with preoperative intraocular pressure less than 21 mmHg, and to detect the associated factors. METHODS: A retrospective study of primary angle closure glaucoma patients was conducted on who underwent cataract surgery or combined with goniosynechialysis from March 2015 to April 2018. Main outcome measures were visual acuity, intraocular pressure, number of glaucoma medications and complications. RESULTS: Sixteen patients (19 eyes) were included. The mean age was 64.89 ± 11.68 years and the mean followed up duration was 21.89 ± 7.85 months. The final visual acuity was significantly improved from 0.69 ± 0.55 to 0.46 ± 0.52 logMAR, within 12 (63.2%) eyes improved, 4 (21.1%) eyes kept unchanged, and 3 (15.8%) eyes reduced. Linear regression analysis indicated that higher mean deviation, higher visual field index and lower glaucoma stage associated with better final visual acuity (r = − 0.511, r = − 0.493, r = 0.537 respectively). Moreover, the final number of medications were reduced from 1.26 ± 0.99 to 0.26 ± 0.56 (p < 0.01). The mean intraocular pressure was not significantly reduced with the final IOP of 14.48 ± 3.74 mmHg (p = 0.97). While the eyes with intraocular pressure above 15 mmHg was decreased to 6 (31.6%) eyes compared to 10 (52.6%) eyes at baseline. Moreover, the number of eyes free of medications was increased from 4 (21.1%) preoperatively to 15 (78.9%) eyes postoperatively. CONCLUSIONS: Final visual acuity was significantly improved in the severe and end stage primary angle closure glaucoma patients and the number of eyes came off medications increased by 57.8% after cataract surgery. Preoperatively, the glaucoma stage, mean deviation and visual field index are important parameters to predict the final visual acuity after cataract surgery.