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

• Main Author: Tan, Wylie
• Other Authors: Westall, Carol
• Language: en_ca
• Published: 2012
• Subjects: Type 1 Diabetes; adolescents; diabetic retinopathy; multifocal electroretinogram (mfERG); slow flash multifocal electroretinogram (sf-mfERG); oscillatory potentials (OP); adaptive optics (AO) retinal imaging; cone photoreceptor density; scanning laser ophthalmoscope; spatial mapping; neural retina; inner plexiform layer; dysfunction; localized damage; vulnerability; 0381
• Online Access: http://hdl.handle.net/1807/33569

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.