Abstract
Purpose:
To evaluate dynamic changes of retinal blood flow (RBF) and choroidal blood flow (CBF) after an intravitreous injection of bevacizumab (IVB) in patients with diffuse diabetic macular edema (DDME).
Methods:
Fourteen eyes of 10 patients with DDME without any previous treatments received 1.25mg/0.05ml IVB. RBF and CBF were assessed with mean blur rate (MBR) measured by laser speckle flowgraphy (LSFG) of the optic disc and fovea before and after 1, 4 and 12 weeks of IVB. Central macular thickness (CMT) measured by optical coherence tomography and best-corrected visual acuity (VA) using a logMAR chart was also evaluated during the clinical course.
Results:
After IVB, RBF was reduced to 78.2±9.6% at 1 week, 79.6±7.6% at 4 weeks and 87.8±7.4% at 12 weeks, while CBF was reduced to 88.3±5.4% (1wk), 89.1±5.2% (4wks) and 88.8±5.2% (12wks). Reduction ratio of CMT was 62.5±5.2% (1wk), 61.8±5.8% (4wks) and 78.9±6.1% (12wks), each of which was significantly correlated with RBF but not with CBF. Improvement of VA was 0.18±0.11 (1wk), 0.17±0.14 (4wk) and 0.11±0.12 (12wks), each of which was correlated with reduction ratio of CMT, but neither with RBF nor CBF.
Conclusions:
Although the exact mechanism of reduction effect of IVB on DDME remains unclear, IVB suppressed both RBF and CBF, and suppression of RBF is possibly related with the pathogenesis of DDME. Improvement of VA is likely to depend upon reduction ratio of CMT, but not upon RBF nor CBF.
Keywords: 499 diabetic retinopathy •
585 macula/fovea •
505 edema