Permanent monoparesis in a dog after intramedullary injection of iohexol into the lumbar spinal cord

CASE HISTORY: An 8-year-old, spayed, Doberman Pinscher bitch presented for assessment of acute hindlimb paresis.

CLINICAL FINDINGS: During a lumbar myelographic contrast study a small volume of iohexol contrast agent was inadvertently injected into the cord parenchyma. After surgical hemilaminectomy for an intervertebral disc extrusion at L1–2 the dog recovered use of one hindlimb, but had ongoing extensor weakness of the left hindlimb. Left femoral nerve function had not returned after 14 months.

DIAGNOSIS: EMG findings 14 months after the incident indicated persistent femoral neuropathy consistent with the intramedullary contrast injection at L3–4.

CLINICAL RELEVANCE: Inadvertent deposition of iohexol into spinal cord parenchyma may be rare, but if it occurs it can have long-lasting consequences.