MRI of Congenital Arteriovenous Malformation in Wistar Rats: the Effect of Altering Diffusion Tensor Imaging in Accessing White Matter Integrity

Tsang-Wei Tu¹, L. Christine Turtzo¹, Jacob D. Lescher¹, Dana D. Dean¹, Tiziana T. Coppola¹, Rashida A. Williams¹, Joseph A. Frank¹

Congenital hydrocephalus was accidentally found in the baseline scan of Wistar rats used in TBI study. MRI techniques were performed including: MRA, SWI, and DTI, to diagnose cerebral abnormalities including arteriovenous malformation (AVM). The existence of AVM nidus was confirmed by post-mortem micro-CT images. Compared to normal rats, AVM rats had significantly lower FA, higher MD, AD, and RD, suggesting the white matter integrity was congenitally different in hydrocephalic rats. Their abnormal diffusion patterns may result in a false interpretation of pseudo-increase of axonal integrity. Baseline scans are strongly suggested to prevent using these AVM rats in studying neurological diseases.