Early Pathological Changes in the Optic Nerves of Type-I Diabetic Rats Revealed by Directional Diffusion-Weighted MRI

Lifeng Gao¹, Mingming Huang¹, Hao Lei¹

Type-I diabetes was induced in rats by a single injection of streptozotocin (STZ). Directional diffusion-weighted imaging on the optic nerves were performed at 4 weeks and 10 weeks on a 4.7 T scanner to monitor the early pathological changes induced by diabetes. Water diffusivities parallel and perpendicular to the axonal tracts were measured by the apparent diffusion coefficients ADC_// and ADC(perpendicular), respectively. Compared to the control animals, the STZ-treated animals showed a trend of reduced ADC(perpendicular) in the optic nerves at 4 weeks, and significantly decreased ADC(perpendicular) at 10 weeks, but insignificant changes in ADC_// at these time points.