Factors influencing visual acuity after intravitreal triamcinolone acetonide as treatment of exudative age related macular degeneration

Aim: To evaluate factors influencing change in visual acuity (VA) after intravitreal injection of triamcinolone acetonide as treatment of exudative age related macular degeneration (AMD). Methods: This prospective, interventional, comparative non-randomised clinical case series study included 94 patients (99 eyes) showing progressive exudative AMD with occult (n=61 eyes), minimally classic (n=18), predominantly classic (n=1), or totally classic (n=8) subfoveal neovascularisation. Mean follow up was 8.5 (SD 4.7) months (median, 7.3 months; range 3.1-24.5 months). All patients received an intravitreal injection of 20-25 mg of triamcinolone acetonide. Results: An increase in best VA of at least one line on the Snellen charts was found in 63 (63.1%) eyes. Correspondingly, mean VA increased significantly (p<0.001) from 0.17 (SD 0.13) to 0.22 (SD 0.17) after the injection. Postoperative increase in VA was significantly (p<0.001) and negatively correlated with preoperative VA (correlation coefficient, -0.49). Gain in visual acuity was significantly (p=0.009) higher if preoperative visual acuity was less than 0.08 (gain: 3.2 (SD 2.9) Snellen lines) than if preoperative VA ranged between 0.08 and 0.20 (gain: 1.2 (SD 2.2) Snellen lines). Change in VA was significantly (p=0.016) less if preoperative VA was higher than 0.20 (change: -0.8 (SD 3.4) Snellen lines). Maximal gain in VA was significantly (p=0.035) larger in eyes with retinal pigment epithelium detachment than in eyes with minimally classic subfoveal neovascularisation. This was statistically independent of age (p=0.99), refractive error (p=0.88), sex (p=0.92), and duration of follow up (p=0.46). Conclusions: Gain in VA after intravitreal injection of 20-25 mg of triamcinolone acetonide is significantly and negatively correlated with preoperative VA. It is significantly larger in eyes with retinal pigment epithelium detachment than in eyes with minimally classic subfoveal neovascularisation.