Abstract
Purpose: :
To report the effect of intravitreal ranibizumab in patients with visual loss due to macular edema secondary to diabetes and retinal venous occlusive disease.
Methods: :
The medical records of patients with a diagnosis of macular edema secondary to diabetic retinopathy (DR) or retinal venous occlusive disease [(VO) to include central retinal venous occlusion and branch retinal venous occlusion] who had undergone intravitreal ranibizumab injection (0.5 mg/0.05ml) were reviewed. Complete ophthalmological examination including visual acuity, dilated fundus examination and optical coherence tomography was performed. Data recorded included: pre injection Snellen visual acuity and central macular thickness (CMT) on Optical Coherence Tomography (OCT), post injection VA and CMT, and the number of injections given. Snellen visual acuities were converted to LogMAR for the purpose of comparison.
Results: :
71% of the patients had visual loss secondary to diabetic macular edema. At the time of submission, baseline central macular thickness of the DR Group was 373.6 µm ± 125 compared to 535 µm ± 88 for the VO group. At baseline prior to injection, the visual acuity was at least 2 lines better in the DR group (0.73 ± 0.39) compared to the VO group (1.38±0.75). Most patients in both groups showed a decrease in CMT after injection. Post-injection CMT among the DR group was 344.4 µm±104. Post-injection CMT among the VO group was 398.8 µm±152. At the end of follow-up time, the mean change in CMT among the DR group was 43.9 µm compared to 136.3 µm for the VO group. 75% of subjects showed improvement in VA in the DR group as compared to only 50% of the VO group. The post-injection VA average for the DR group was 0.63 compared to 0.88 for those with VO.
Conclusions: :
In our study, CME is more severe in venous occlusive disease compared to diabetic retinopathy as shown by increased CMT on OCT. The amount of decrease in CMT following intravitreal ranibizumab injection is greater in patients with venous occlusive CME compared to DME. Likewise, the amount of improvement in visual acuity with venous occlusive disease is greater compared to DR. However, the overall prognosis for visual improvement remains better in diabetic CME compared to venous occlusive CME. Our findings may be affected by chronicity and duration of disease. Both groups responded well morphologically as evidenced by decrease in CMT, but this change does not necessarily correlate with degree of visual improvement.
Keywords: edema • macula/fovea • injection