Intravitreal triamcinolone acetonideversuscombined intravitreal bevacizumab and dexamethasone in diffuse diabetic macular oedema

Abstract

To compare the efficacy of a single injection of combined intravitreal dexamethasone and bevacizumab (Avastin) with that of intravitreal triamcinolone acetonide in eyes with diffuse cystoid diabetic macular oedema. Prospective, non-randomized, masked, interventional case series. Twenty-four eyes of 24 subjects with centre-involved diabetic macular oedema extending over two disc-areas with predominant cystic changes on spectral domain optical coherence tomography were selected. Ten phakic and two pseudophakic, ocular hypertensive eyes received intravitreal dexamethasone and bevacizumab as against 12 pseudophakic, normotensive eyes that received intravitreal triamcinolone acetonide. Change in central macular volume on spectral domain optical coherence tomography and best-corrected visual acuity were measured at 6-week follow-up. Baseline data were matched in both groups. Post-injection central macular volume (7.46 ± 0.73 mm(3)) was significantly lower (P < 0.001) in the intravitreal triamcinolone acetonide group when compared with its pre-injection central macular volume (9.11 ± 1.0 mm(3)) or when compared with the post-injection central macular volume (P = 0.02) of the intravitreal dexamethasone and bevacizumab group (8.42 ± 1.18 mm(3)). However, post-injection best-corrected visual acuity between the intravitreal triamcinolone acetonide (0.65 ± 0.15 logMAR) and the intravitreal dexamethasone and bevacizumab groups (0.685 ± 0.15 logMAR) was not significantly different (P = 0.06) at 6 weeks. No significant correlation was noted between change in central macular volume and change in best-corrected visual acuity (r = 0.35, P = 0.07) from the pooled data of both the groups. A fair correlation was noted between change in central macular volume and pre-injection central macular volume (r = 0.55, P = 0.005). Intravitreal triamcinolone acetonide may be more effective than intravitreal dexamethasone and bevacizumab in reducing macular volume in patients with diffuse cystoid diabetic macular oedema. A significant reduction in macular volume does not necessarily translate into a correspondingly significant improvement in best-corrected visual acuity.