Purpose: To evaluate the characteristics of microaneurysms seen on color fundus photography, fluorescein angiography, and spectral-domain optical coherence tomography in diabetic retinopathy.
Methods: One hundred and thirty-two consecutive eyes of 92 patients with diabetic retinopathy were reviewed retrospectively. The characteristics of microaneurysms, including capsular structure (ring sign), hyperreflective spots in the lumen, the retinal layers in which they are located, and adjacent cystoid spaces, were documented on spectral-domain optical coherence tomography as sectional images. Their appearance on fundus photographs and focal fluorescein leakage were recorded. The association among these characteristics was evaluated.
Results: Eighty-eight of 118 microaneurysms (74.6%) with no capsular structure had focal fluorescein leakage, whereas 7 of 34 microaneurysms (20.6%) with complete capsular structure had leakage (P < 0.001). Focal leakage from the microaneurysms correlated positively with hyperreflective spots in the lumen and nearby cystoid spaces (P = 0.013 and P < 0.001, respectively) but not in the layers in which they were located. Multicolored microaneurysms contained hyperreflective spots in the lumens more frequently than whitish or reddish spots (P = 0.038), compared with no significant associations between the appearance and the other optical coherence tomography characteristics.
Conclusion: Focal fluorescein leakage from microaneurysms was associated positively with the absence of a capsular structure, hyperreflective spots, and nearby cystoid spaces.