RUPTURED DISTAL ACCESSORY ANTERIOR CEREBRAL-ARTERY ANEURYSM - CASE-REPORT

OBJECTIVE AND IMPORTANCE: Accessory anterior cerebral artery (ACA), wh ich is a type of median artery of anomalous triplicate ACA, is not rar e, but aneurysmal formation is extremely rare. We report a rare case w ith ruptured aneurysm arising from a distal accessory ACA. We discuss the characteristics and causes of this type of aneurysm and classifica tion of this anomaly. CLINICAL PRESENTATION: A 63-year-old man suddenl y developed severe headache and then loss of consciousness and paraple gia. Computed tomography disclosed thick and diffuse subarachnoid hemo rrhage and interhemispheric hematoma. Subsequent bleeding occurred 2 h ours after the first hemorrhage. Cerebral angiography disclosed a sacc ular aneurysm arising from the distal accessory ACA. INTERVENTION: Nec k clipping of the aneurysm was performed 22 hours after the second epi sode, using an interhemispheric approach. CONCLUSION: Although transie nt paraplegia occurred 8 days after onset, the patient recovered well after surgery without neurological deficit. The characteristics of the aneurysm arising from distal accessory ACA are considered similar to those of distal ACA aneurysm. There is, however, some confusion regard ing the terminology of the anterior communicating artery complex anoma lies, which we discuss.