2018 年 46 巻 1 号 p. 71-75
We present a rare case of callosal disconnection syndrome caused by rupture of an anterior communicating artery aneurysm (Acom AN). A 51-year-old man with a consciousness disturbance was transported to our hospital. Head computed tomography showed subarachnoid hemorrhage (SAH) associated with thick hematoma in the pericallosal cistern. Three-dimensional computed tomography angiography (3D-CTA) suggested that a forward-projected Acom AN was a potential source of the bleeding. We used a left pterional approach based on these findings. Neck clipping was performed according to the intraoperative finding that the source of the bleeding was a backward-projected Acom AN which could not be seen on 3D-CTA images. On awakening after surgery, the patient had a callosal disconnection syndrome. An Acom AN can rupture in the case of SAH associated with thick hematoma localized to the pericallosal cistern. Surgery should be based on consideration of this possibility in addition to that of a mechanism in which the Acom AN jets backward.