Differences in cross-sectional retinal scans of diabetics vs
A Study was conducted to examine the subtle differences in the structure of diabetic vs. control retinas.

Spectral-domain optical coherence tomography (SD-OCT) images were compared for the retinas of 33 diabetic subjects who did not have clinical evidence of diabetic macular edema and age-matched controls, with central macular thicknesses of 275 and 276 microns, respectively.

Cross-sectional retinal images through the fovea, called B-scans, were analyzed for spatial frequency content. The B-scans were processed to remove and smooth the portions of the retinal image not within regions of interest in the retina. The remaining retinal images were then quantified using a Fast Fourier Transform (FFT) approach that provided amplitude as a function of spatial frequency.

--The FFT analysis showed that diabetic retinas had spatial frequency content with significantly higher power compared to control retinas particularly for a deeper fundus layer at mid-range spatial frequencies, ranging from p = 0.0030 to 0.0497 at 16.8 to 18.2 microns/cycle.

--There was lower power at higher spatial frequencies, ranging from p = 0.0296 and 0.0482 at 27.4 and 29.0 microns/cycle.

--The range of mid-range frequencies corresponds to the sizes of small blood vessel abnormalities and hard exudates. Retinal thickness did not differ between the two groups.

Finally, diabetic retinas displayed slight but detectable pattern changes in SD-OCT pictures, particularly in the deeper fundus layers, despite not being thicker than controls. This pattern's size range and distribution in diabetic eyes were consistent with small blood vessel anomalies and lipid and fluid leaks. Feature-based biomarkers may be used to supplement retinal thickness parameters for diabetic eye problems management and to detect early alterations.

Source: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0253091