Abstract
Purpose: :
To determine the incidence of a rebound macular edema after an intravitreal injection of bevacizumab (Matsumoto et al. 2007), and to identify the pre-treatment factors that were associated with the rebound in eyes with macular edema secondary to branch retinal vein occlusion (BRVO).
Methods: :
The foveal thickness was measured monthly in 65 eyes of 65 patients with macular edema secondary to BRVO. All of the patients had received an intravitreal injection of bevacizumab (1.25 mg/0.05 ml). A rebound of macular edema was defined as an increase in foveal thickness to a thickness greater than that of the pre-treatment thickness. Multivariate logistic regression analyses were performed with rebound macular edema as the dependent variable. A simple comparison of the pre-treatment factors between the eyes with and without a rebound was also performed.
Results: :
A rebound of macular edema was seen in eight of 65 eyes (12.3%) at 8 to 12 weeks (mean, 9.1 weeks) after the injection. Both logistic regression analyses and simple comparisons showed that the shorter intervals between symptom onset to the initiation of treatment and lower pre-treatment foveal thickness were significantly associated with a rebound of macular edema. The interval from symptoms onset to the initiation of treatment was within 8 weeks in all eight eyes with rebound macular edema.
Conclusions: :
These results suggest that a rebound of macular edema in BRVO was more likely to occur when the bevacizumab therapy was initiated before the macular edema reaches the maximum level.
Keywords: edema • retina • clinical (human) or epidemiologic studies: prevalence/incidence