Localizing Structural and Functional Damage in the Neural Retina of Adolescents with Type 1 Diabetes

Studies demonstrate neuro-retinal damage in patients with diabetes and no clinically visible diabetic retinopathy. It is unknown which retinal regions are most vulnerable to diabetes. We hypothesized that the standard and slow-flash (sf-) multifocal electroretinogram (mfERG) and adaptive optics (AO) imaging will localize retinal regions of vulnerability.;Fifty-five adolescents with diabetes and 54 controls underwent mfERG testing to isolate predominately retinal bipolar cell activity and sf-mfERG testing to isolate three oscillatory potentials (OPs) from intraretinal amacrine and interplexiform cells. Greatest mfERG delays were in the superior temporal quadrant and at 5°-10° eccentricity. Greatest sf-mfERG delays were found at different eccentricities for each OP.;Twenty adolescents with diabetes and 14 controls underwent AO imaging. No significant differences in cone photoreceptor density were found; however, patients showed a trend towards reduced density in the superior nasal region.;Inner retinal structures may be more susceptible to damage by diabetes than outer retinal structures.