Conjunctival TGF-B Level in Primary Augmented Trabeculectomy

To compare the levels of conjunctival transforming growth factor beta (TGF-β) between glaucoma and control patients and to determine conjunctival TGF-β levels before and 3 months after augmented primary trabeculectomy.

Patients with primary open angle glaucoma (POAG) or primary angle closure glaucoma (PACG) admitted for mitomycin (MMC) augmented primary trabeculectomy due to failure in achieving target pressure after maximum medical therapy were selected. Age-matched non-glaucoma patients were controls. Impression cytology of the conjunctiva was obtained twice from glaucoma patients (1 week before augmented primary trabeculectomy and 3 months after surgery) and once from controls. Conjunctival cells were tagged with an anti-TGF-β antibody and analyzed by flow cytometry.

Eighteen patients (11 POAG and 7 PACG patients) and 18 age-matched control patients were included. Conjunctival TGF-β levels were significantly different between glaucoma (35.21% ± 14.12%) and control patients (14.96% ± 6.34%) (p = 0.001). There was a significant reduction in conjunctival TGF-β levels after augmented trabeculectomy (23.0% ± 13.8%) (p < 0.001). A significantly greater reduction in conjunctival TGF-β levels (61.6% ± 17.9%) was associated with complete success of trabeculectomy at 3 months (83.3%) after surgical intervention (p = 0.029).

The reduction of TGF-β on the conjunctival post primary augmented trabeculectomy may suggest TGF-β as potential predicting marker of short term trabeculectomy success. However, the result may be affected by site of impression, topical pressure lowering drugs and small sample size.