Outcome of combined trabeculectomy with cataract surgery in patients on prostaglandin analogs and aqueous suppressants

Abstract

Purpose: To compare the effect of prostaglandin analogs (PGA) against other glaucoma medications (non-PGA) on the intraocular pressure (IOP) outcomes of combined trabeculectomy with phacoemulsification, and the conjunctival cell profile in persons with primary open-angle (POAG) and pseudoexfoliation glaucoma (PXFG). Methods: A prospective cohort study was conducted among 116 patients with POAG or PXFG on glaucoma medications for a minimum of 3 months undergoing glaucoma triple procedure. Patients were divided into two groups (PGA and non-PGA) based on preoperative exposure to PGA. IOP outcomes were assessed for up to 2 years. Conjunctival biopsy specimens were obtained at the time of surgery, and histopathological analysis was performed. Results: Forty-two patients were in the PGA group, 67 were in the non-PGA group, and seven were lost to follow-up. The non-PGA group had lesser mean postoperative IOP and needed fewer postoperative medications compared to the PGA group in all visits up to 2 years. The non-PGA group had better complete success rate (50.7% vs. 14.3%, P < 0.001). Kaplan–Meier survival estimates showed a significant difference in cumulative complete success rate between non-PGA (67%) and PGA (26%) by 24 months (P < 0.001). The Cox proportional model showed the type of drug to be significantly associated with surgical failure. Histopathological analysis revealed that the PGA group had higher numbers for each type of inflammatory cell (except mast cells) compared to the non-PGA group. Conclusion: Patients on PGA are likely to have a higher postoperative IOP and may need more medications for IOP control after a glaucoma triple procedure.