Abstract
Purpose :
To compare the ability of color retinal photographs, spectral domain optical coherence tomography and adaptive optics in detecting hard exudates (HE) with decreasing size (HE, foci and micro foci) in patients presenting diabetic retinopathy.
Methods :
Patients with diabetic retinopathy were studied. A multimodal imaging of an area of clinically visible exudates was conducted: a 45-degree retinography (Nonmyd 7 Retinal Camera, Kowa Company Limited, Nagoya,Japan), together with a spectral domain OCT with en-face reconstruction (Spectralis, Heidelberg Engineering, Heidelberg, Germany) and an adaptive optics imaging (RTX1, Imagine Eye, Orsay, France) were performed. Hard exudates (>50μm), foci (30-50μm) and microfocis (<30μm) were counted and were measured, in a blind manner by two examiners. The Kendall rank correlation coefficient was calculated as a measure of reliability between the pairs of imaging modalities.
Results :
Fourteen eyes of 11 diabetic patients were studied. Hard exudates from 29 regions of interest were studied.Mean central macular thickness was 370um. The intermodality agreement for hard exudates count was good (Kendall Tau > 0.6, p<0.0001). For smaller exudates, there was a significant discrepancy between the different imaging modalities. Adaptive optics, and in less proportion OCT, showed that hard exudates were made of the aggregation of round deposits corresponding to focis. They also imaged deposits of a few microns not visible on photographs, that shared some characteristics with focis.
Conclusions :
Intermodality agreement was relatively good for larger exudates. However, when it comes to study smaller structures, adaptive optics has shown to be superior. This imaging technique was the only one to accurately show exudates never described before, smaller in size than foci, we labeled micro foci.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.