The Effect of Early Posttrabeculectomy Bleb Leakage on Surgical Outcome: A Prospective Cohort Study.

Purpose: To evaluate the effect of early posttrabeculectomy bleb leakage on trabeculectomy surgery outcomes and success rate.

Methods: The present prospective cohort study was conducted on 203 eyes of 203 patients who underwent trabeculectomy at Torfeh and Imam Hossein Medical Centers, Tehran, Iran, between 2016 and 2021. Patients were divided into two groups: those with early bleb leakage (within the 1^st month of surgery) and those without bleb leakage. The success rate of surgery was compared 12, 18, and 24 months after surgery in the two groups. The average intraocular pressure (IOP) and the need for medications in patients 1, 3, 6, 9, 12, 18, and 24 months after the trabeculectomy were also compared.

Results: Bleb leakage was detected in 33 eyes during the 1^st month after a trabeculectomy (16.3%). The mean decrease in IOP in the group with leakage was significantly lower than in patients without leakage at 1, 6, 9, 12, 18, and 24 months after surgery (P < 0.05). The need for antiglaucoma medication was significantly higher among patients with bleb leakage at 3 months (P = 0.04) and 9 months (P = 0.047) after surgery (P < 0.05). The success rate at 12, 18, and 24 months after surgery was significantly lower in the group with leakage than the group without.

Conclusions: The results of our study suggest that early posttrabeculectomy bleb leakage negatively impacts surgery success. Furthermore, IOP reduction was lower in patients with early leakage.