Prospective study of intravitreal triamcinolone acetonide versus bevacizumab with or without laser for macular edema secondary to retinal vein occlusion

Abstract

Objective: To assess difference in visual outcome, macular thickness and need for laser treatment in patients receiving intravitreal triamcinolone acetonide or bevacizumab for macular oedema secondary to retinal vein occlusion. Design: Open labeled prospective randomised controlled trial, evaluating 38 retinal vein occlusion patients. 19 patients each were assigned, to Intravitreal Triamcinolone Acetonide (IVTA) and Bevacizumab (IVB) group. Methodology: Baseline ocular parameters like best corrected visual acuity (BCVA), intraocular pressure (IOP) by Applanation tonometry, fundus examination using indirect ophthalmoscope, slit lamp biomicroscopy, Ocular Coherence Tomography of the macula and Fundus Flourescein Angiography performed. Under aseptic conditions, Injection of 4 mg (0.1 ml) Triamcinolone Acetonide (Kenacort) or 1.25 mg (0.05 ml) Bevacizumab (Avastin) was injected into the vitreous. Patients were given re-injections or laser treatment according to requirement. BCVA and IOP at 15 days, 1, 3 and 6 months post injection was recorded. OCT and FFA were repeated at 3 and 6 month. Outcome: At 6 months, patients with BRVO receiving IVTA, there was significant improvement in visual acuity (p = 0.014), as well as decrease in macular edema (p ≈ 0.000), whereas patients of BRVO in the IVB group did not show significant improvement in visual acuity (p= 0.375). Visual acuity of CRVO patients in the IVTA (p = 0.178) and IVB (p = 0.109) group did not show any significant improvement. Though there was significant decrease in macular edema in both IVTA (p ≈ 0.000) and IVB (p =0.042) groups. No significant increase in IOP was noted in either IVTA (p= 0.089) or IVB (p = o.637).Results and Conclusion: The results show a favourable influence of IVTA on BCVA at 6 months.Positive effect in decreasing central macular thickness (CMT) was observed in patients receiving IVTA and IVB.FFA guided laser photocoagulation helps in stabilizing the visual acuity and prevents vision threatening complications. Changes in OCT can be used to monitor patient response to treatments for CRVO related macular oedema. Summary: IVTA injection when combined with FFA guided laser in BRVO eyes showed most favourable outcome in terms of both visual improvement and CMT during follow up period of 6 months.