Abstract
Purpose:
To analyze early signs of diabetic retinopathy in type 2 diabetic patients using an adaptive optics (AO) retinal camera, in comparison with fluorescence angiography (FA).
Methods:
31 patients with type 2 diabetes were enrolled in the study (age mean 54, range 28-82). The patients underwent standard ophthalmoscope and fluorescence angiography (FA) examination. Additionally high-resolution retinal images were acquired using an AO retinal camera (rtx1™, Imagine eyes, France) in the central 16 deg x 8 deg macular area of one eye of each patient. The AO images were evaluated for the presence of micro-aneurisms and white membrane-like high intensity area. The relations between findings from AO and FA were analyzed.
Results:
Based on standard ophthalmoscope examination, 24 patients were affected by non proliferative diabetic retinopathy (NPDR) while 7 showed no sign of retinopathy. AO images revealed white membrane-like high intensity area in 6 cases (19%), mainly in areas that surrounded the branching of retinal vessels. The relation between the presence of such white membrane-like high intensity area in AO images and leakage in FA was not statistically significant (McNemar test). These membranes were not visible with the FA or color fundus images, although all the cases with the membrane showed leakage in elsewhere by FA. The detection of micro-aneurisms with AO and FA produced identical results in 29 cases (94%). In one of the remaining two cases, AO revealed micro-aneurisms that were not detected using FA.
Conclusions:
White membrane-like high intensity area may reflect the early proliferative change. Our result suggests that the proliferative change could have started early diabetic retinopathy stages. Adaptive optics retinal camera might be useful to detect very early sign of proliferative change in NPDR patients. Further studies will be needed to confirm whether the white membranes are related to proliferative change by follow up studies.