Changes in Retinal Nerve Fibre Layer Thickness Following Trabeculectomy in Primary Open-Angle Glaucoma: A Prospective Study
Mehraj R. Chowdhury, Ashraful H. Ridoy, Mahziba R. Chowdhury, Nawreen B. AnwarAbstract
Purpose:
To evaluate changes in retinal nerve fibre layer (RNFL) thickness following trabeculectomy in patients with primary open-angle glaucoma (POAG) using optical coherence tomography (OCT).
Methods:
This prospective observational study included 29 eyes of 29 POAG patients undergoing trabeculectomy at a tertiary eye care centre over the period of 6 months. RNFL thickness was measured using OCT one week prior to surgery and at 1 month and 3 months postoperatively. Global and quadrant-wise (superior, inferior, nasal, temporal) RNFL thickness values were recorded. Intraocular pressure (IOP) was measured at each visit. Data were analysed to compare preoperative and postoperative RNFL thickness and IOP values.
Results:
The change in global RNFL thickness following trabeculectomy showed an increase from 62.72 ± 5.97 μm preoperatively to 63.54 ± 5.35 μm at 3 months (mean change + 0.82 μm; 95% CI, 0.30–1.34; Bonferroni-adjusted
Conclusion:
Trabeculectomy substantially reduced IOP and was associated with a small increase in OCT-measured global RNFL thickness over 3 months, with the maximum change in the superior quadrant. This thickening may reflect postoperative structural changes rather than nerve fibre regeneration. Larger, controlled studies with longer follow-up and structural and functional assessments are needed.