Conus perimedullary arteriovenous fistula with intracranial drainage: Casereport

OBJECTIVE AND IMPORTANCE: Perimedullary arteriovenous fistulae (AVFs) do no t commonly present with subarachnoid hemorrhage or intracranial venous drai nage causing neurological symptoms. We present a case with both of these fe atures. The patient was inadvertently treated for an unruptured intracrania l aneurysm before his true problem was recognized. CLINICAL PRESENTATION: A 65-year-old man presented with sudden-onset lower- extremity weakness, diplopia, nausea, and dysarthria on the day of admissio n. A lumbar puncture documented subarachnoid hemorrhage, and imaging studie s revealed a left middle cerebral artery aneurysm. It was noted during surg ery that this aneurysm was unruptured, and the patient did not exhibit impr ovement after surgery. INTERVENTION: Spinal angiography demonstrated a spinal perimedullary AVF fe eding from the left T12 radicular artery; venous drainage extended rostrall y into the posterior fossa venous system. The AVF was surgically occluded v ia a posterior laminectomy at the level of the AVF. After surgery, the pati ent's symptoms began to abate. CONCLUSION: Conus perimedullary AVFs can have venous drainage that extends as far as intracranial veins, which can lead to confusing clinical findings because the symptoms may suggest an intracranial process, although the les ion is in the spine. Surgeons must be aware of this confusing presentation.