Vertebral artery pseudoaneurysm complicating posterior C1-2 transarticularscrew fixation: Case report

BACKGROUND Vertebral artery injury during posterior C 1-2 transarticular screw fixatio n occurs in approximately 3% of patients and may remain asymptomatic or res ult in arteriovenous fistulae, occlusion, narrowing, or dissection of the v ertebral artery, and lead to transient ischemic attacks, stroke, or death. CASE DESCRIPTION This is the first report of a pseudoaneurysm resulting from damage to the v ertebral artery during the procedure. This 31-year-old male underwent poste rior C1-2 transarticular screw fixation for unstable os odontoideum, Injury to the left vertebral artery occurred while the hole for the left screw wa s being drilled. Temporary control of bleeding with local pressure was foll owed by immediate postoperative angiography that revealed a left vertebral artery pseudoaneurysm. Although the patient remained asymptomatic, therapeu tic anticoagulation was instituted 6 hours postoperatively, Increasing size of the pseudoaneurysm was noted on routine follow-up angiography 4 weeks l ater. Endovascular occlusion of the pseudoaneurysm and left vertebral arter y, with preservation of vertebrobasilar now through the right vertebral art ery, was accomplished without neurological consequence. CONCLUSIONS Vertebral artery pseudoaneurysm complicating posterior C1-2 transarticular screw fixation may be effectively treated with endovascular approaches. (C) 2001 by Elsevier Science Inc.