Abstract
Purpose :
Numerous studies have shown that lowering intraocular pressure (IOP) is beneficial for slowing the progression of glaucoma. While many studies have demonstrated the IOP-lowering effect of cataract surgery in patients with primary open-angle glaucoma (POAG), few studies have specifically evaluated patients with low tension glaucoma (LTG). LTG patients are defined as a group of open-angle glaucoma patients with an untreated IOP that is in the normal range of 8-21mmHg. This study seeks to evaluate the effect of cataract surgery on IOP in LTG patients as compared to those with POAG.
Methods :
A multi-center retrospective chart review of adult patients at Northwestern Memorial Hospital and Loyola University Medical Center who underwent uncomplicated cataract surgery from January 1, 2010 to January 1, 2017 was performed. The patients were subdivided into POAG and LTG. Patients who had a history of prior intraocular surgery, or surgery for glaucoma performed at the same time as cataract surgery, were excluded from the study. Primary outcomes measured include visual acuity (VA), IOP, and number of glaucoma medications pre-operatively and one year post-operatively. Statistical analysis was performed using the paired Student’s t test.
Results :
Eighty-two eyes (59 patients) with LTG, 91 eyes (68 patients) with POAG, and 51 eyes (37 patients) without glaucoma (controls) were analyzed. Mean VA (logMAR) improved significantly in all groups (-0.24 in the LTG group; -0.19 in the POAG group; -0.44 for controls; p<0.00001 for each). Mean IOP at 1 year post-operatively decreased significantly across all groups (-0.9mmHg in the LTG group, p=0.023; -1.2mmHg in the POAG group, p=0.001; -1.1mmHg in the control group, p<0.00001). The number of glaucoma medications did not significantly change in either the LTG or POAG group (p=0.148 for the LTG group; p=0.237 for the POAG group).
Conclusions :
Cataract surgery in LTG, POAG, and control patients resulted in statistically significant visual improvement and IOP reduction at one year. This study is limited by its small sample size, retrospective nature, and brief follow up period. Further investigation is necessary to determine the long term effects of cataract surgery on IOP and outcomes in glaucoma patients, particularly LTG patients.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.