7-year-old, female neutered, Weimaraner presented with a hyperacute-onset monoparesis of the right hindlimb. No obvious signs of hyperesthesia. Neurolocalisation: Lumbar intumescence.
There are 8 lumbar vertebrae. The intervertebral (IV) discs of T13-L1 and L2-L4 are dehydrated with loss of the normal hyperintense signal in T2W.
There is an intramedullary lesion, with ill-defined margins, located at the right lateral aspect of the spinal cord at the level of L4-L5 (lumbar intumescence). These changes extend from the mid L4 to the caudal aspect of L5, occupying a slightly larger medullary diameter at the IV space of L4-L5. The lesion is hyperintense in T2W, isointense in T1W and does not show a susceptibility artifact in T2* (pink arrows), showing a mild contrast enhancement. There is no spinal cord compression at this level.
There is a mild hypertrophy of the dorsal longitudinal ligament at the level of T13-L4 and L7-S1, with a decreased signal of the ventral epidural fat, without evidence of spinal cord compression.
Intramedullary lesion lateralized to the right at L4-L5, consistent with ischemic myelopathy (fibrocartilaginous embolism).