A ruptured dissecting aneurysm of the anterior radiculomedullary artery caused by hypoplastic vertebral artery angiography: case report.

BACKGROUND: Cerebral digital subtraction angiography (DSA) is increasingly utilized in the diagnosis of cerebrovascular disorders. We report a rare case of a ruptured dissecting aneurysm involving the anterior radiculomedullary artery of the cervical spinal cord, precipitated by angiography of a hypoplastic vertebral artery. CASE PRESENTATION: Cerebral computed tomography angiography (CTA) revealed severe stenosis of the M1 segment of the right middle cerebral artery in a 70-year-old woman who presented with paroxysmal weakness affecting the left upper and lower limbs. Dual antiplatelet therapy with aspirin and clopidogrel was initiated. On day 3, cerebral digital subtraction angiography (DSA) was performed. During continuous contrast injection into the right hypoplastic vertebral artery, the anterior radiculomedullary artery-a branch of the vertebral artery at the C6 vertebral level-underwent luminal dilation and subsequently ruptured, resulting in extensive extravasation of contrast medium into the spinal subarachnoid space. Non-contrast head CT confirmed widespread subarachnoid hemorrhage. Following 10 days of conservative medical management, follow-up head CT demonstrated complete resolution of the hemorrhage. The patient was discharged without significant neurological deficits and remained free of recurrent subarachnoid hemorrhage during a 3-year clinical follow-up period. CONCLUSIONS: The occurrence of a ruptured dissecting aneurysm of the anterior radiculomedullary artery induced by vertebral angiography is exceedingly rare. We hypothesize that the sustained high-pressure and high-volume injection of contrast medium was responsible for the arterial dissection and subsequent rupture. During interventional procedures, neurointerventional radiologists should avoid selective angiography of small, hypoplastic vertebral arteries whenever possible to minimize the risk of such complications.