Efficacy and Safety of Intra-operative Posterior Sub-Tenon's Triamcinolone Injection in Cataract Surgery Associated with Diabetic Retinopathy

Materials and Methods: This is a prospective interventional comparative study conducted on 36 eyes of 26 patients with DR and cataract. Patients were randomly assigned to Group I, triamcinolone acetonide (TA) (triamcinolone group) receiving a single posterior sub-Tenon’s TA injection 1 ml (40 mg), at the end of small incision cataract surgery and Group II (control group) who underwent only cataract surgery. Best corrected visual acuity (BCVA) and intra-ocular pressure (IOP) were recorded at baseline and at each follow-up. Fundus fluorescein angio graphy and optical coherence tomography were done at baseline and 3 months postoperatively. Results: The macular thickness in the control group increased by 71 microns (30.45%) at 3 months post-operatively and was statistically significant ( P = 0.006). However, there was no statistically significant difference in the foveal thickness between the groups either at baseline (P = 0.07) or at 3 months (P = 0.63). At 6 months, there was no significant difference in the mean change in foveal thickness between the 2 Groups. There were no statistically significant differences between the groups in BCVA at 1 month (P = 0.38) and 6 months (P = 0.66) post-operatively. Conclusions: The results of our study suggest that a sub-Tenon’s injection of triamcinolone reduced the incidence of cystoid macular edema after cataract surgery in diabetic patients. In addition, it reduced the central macular thickness and improved visual acuity in the short term However, sub-Tenon’s injection of TA did not affect DR progression or visual acuity at 6 months post-operatively which was determined by the pre-operative metabolic status.