A Systematic Correlation of Angiography and High-Resolution Optical Coherence Tomography in Diabetic Macular Edema

Abstract

To correlate leakage patterns in fluorescein angiography (FA) images and retinal morphologic features in high-definition optical coherence tomography (HD OCT) images in diabetic macular edema. Prospective pilot study and case series. Nine consecutive patients (10 eyes) with diabetic macular edema. All patients were examined using FA (HRA 2; Heidelberg Engineering) and HD OCT (Carl Zeiss Meditec; resolution, 512x128 pixels, 5.8x5.8 mm, and high-resolution scans consisting of 4096 A scans) on the same day. Using Adobe Photoshop (CS2 Version 9.0; Adobe Systems Incorporated, San Jose, CA) a grid containing 15x7 fields was superimposed on the HD OCT en face image and a late-phase FA image according to retinal landmarks. In each patient, a standardized analysis of 105 subfields was performed to provide a characterization of the type of vascular leakage in FA and the associated retinal morphologic changes in corresponding locations. Angiographic leakage type and structural alteration in retinal morphologic features in OCT. There was a high consistency between FA and OCT in the petaloid pattern of hyperfluorescence that correlated with the presence of large cystic spaces in the outer nuclear layer (ONL) and the outer plexiform layer (OPL) with or without subretinal fluid in 30.4% and 69.6% of graded fields, respectively. A honeycomblike pattern of hyperfluorescence was associated with swelling and cystic spaces in ONL, OPL, the inner nuclear, and the inner plexiform layer in 71.4% of graded fields. Diffuse patterns of hyperfluorescence did not correlate with characteristic retinal changes in HD OCT, but rather showed diversity in the type of morphologic alteration. The presence of central fluid pooling, such as subretinal fluid, could be identified only by HD OCT and not by FA. In the examined patients, a petaloid pattern and a honeycomb pattern of hyperfluorescence observed in FA were found to correlate to characteristic changes in HD OCT, whereas a diffuse leakage pattern was associated with nonuniform changes in retinal morphologic features. The author(s) have no proprietary or commercial interest in any materials discussed in this article.