Objective: To determine the outcomes of trabeculectomy surgery and predictors of post-operative Intra Ocular
Pressure (IOP) among glaucoma patients attending Ruharo Eye Centre.
Materials and Methods: In a clinical audit conducted from January to June 2016, we reviewed records of all
patients who had undergone trabeculectomy at Ruharo Eye Centre (REC), at least in one eye prior to recruitment.
We made phone calls to patients inviting them for a clinical examination. For the patients who turned up, we
recorded their Best Corrected Visual Acuity (BCVA), Visual Fields (VFs), Intra Ocular Pressure (IOP), Cup-Disc
Ratio (CDR), and any post-operative complications. We also asked patients about their general satisfaction with
both the operation and vision. We did a before and after comparison analysis on several outcome measures
using STATA v14. These included: visual acuity, intra ocular pressure, cup disc ratio and visual field. We defined
treatment success as a post-operative IOP reduction of 40% from baseline and analyzed for its predictors in a
multivariate regression model.
Results: Sixty-two eyes of 38 patients were included in this study. Median age was 66 years (range 24 to 91
years). Median observation time was 2.8 years (range 0.2-4.6 years). Overall treatment success rate was 95%.
Mean IOP pre-and post-operatively was 32 mmHg (95% CI 29.3-34.7) and 12.9 mmHg (11.7-14.2) respectively,
P=0.001; there was no significant worsening of visual acuity and visual field loss. Mean visual acuity Log MAR pre
and post-operatively was 0.58 (95% CI 0.48-0.68) and 0.65 (95% CI 0.52-0.78), P=0.21. Mean visual field defect
was 23.4 (95% CI 21.4-25.5) and 22.9 (95% CI 20-9-25.0), P=0.44.
Conclusion: Trabeculectomy in our setting seemed to have a good success rate and provided good IOP control,
preservation of vision and visual fields.
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