CHANGES IN RETINAL NERVE FIBER LAYER THICKNESS ON HEIDELBERG RETINAL TOMOGRAPHY IN PATIENTS OF PRIMARY OPEN ANGLE GLAUCOMA AFTER TRABECULECTOMY VERSUS ANTI GLAUCOMA MEDICATION

OBJECTIVE: To compare the retinal nerve fiber layer (RNFL) thickness changes in patients of primary open-angle glaucoma after trabeculectomy versus anti-glaucoma medication. METHODS: This quasi-experimental study was conducted from 10 February, th2017 to 28 February, 2018 on 60 patients presenting to the Institute of Ophthalmology, Mayo Hospital, Lahore, Pakistan using non-probability consecutive sampling. Patients were assigned to two equal groups: group A (n = 30) patients underwent trabeculectomy while group B (n = 30) patients were put on anti-glaucoma medication. Pre-treatment and three months post-treatment RNFL thickness was recorded and then analyzed using SPPSv.18.0. RESULTS: Out of 60 patients, Group A (n = 30) had 14 (46.71%) males and 16 (53.31%) females, while Group B (n = 30) had 16 (53.31%) males and 14 (46.71%) females. The mean age was 55.901 +/- 4.221 and 55.431 +/- 3.971 years in Group A and Group B respectively (p = 0.661). In age group, 16 (53.31%) each in Group A and Group B were <55 years. Hypertensive status showed 9 (30.01%) and 5 (16.71%) hypertensive patients in Group A and Group B respectively. Mean change in RNFL thickness was 0.028 +/- 0.012 mu and 0.013 +/- 0.007 mu in Group A and Group B respectively (p = <0.001). Pre and post-treatment (pre:post) RNFL thickness (mu) in males, females, hypertensive, non-hypertensive, age <55 years, and age <= 55 years was 0.201 +/- 0.175 mu : 0.226 +/- 0.155, 0.205 +/- 0.159 : 0.233 +/- 0.019, 0.193 +/- 0.015 : 0.223 +/- 0.013, 0.206 +/- 0.015 : 0.233 +/- 0.018, 0.208 +/- 0.015 : 0.232 +/- 0.021, and 0.196 +/- 0.016 : 0.228 +/- 0.015 for Group A and 0.211 +/- 0.018 : 0.224 +/- 0.019, 0.201 +/- 0.015 : 0.215 +/- 0.014, 0.214 +/- 0.015 : 0.226 +/- 0.016, 0.205 +/- 0.018 : 0.218 +/- 0.017, 0.206 +/- 0.017 : 0.219 +/- 0.015, and 0.209 +/- 0.019 : 0.221 +/- 0.020 for group B respectively. CONCLUSION: Trabeculectomy increases thickness of retinal nerve fiber layer more than anti glaucoma medication.