Abstract
We report a rare case of multiple true posterior communicating artery aneurysms that were difficult to diagnosis preoperatively. An 83-year-old female presented with sudden onset of headache and was diagnosed as having subarachnoid hemorrhage. Angiography and three-dimensional computed tomography angiography (3DCTA) demonstrated both an anterior communicating artery (Acom) aneurysm and a posterior communicating artery (Pcom) aneurysm. Surgery was performed by the right pterional approach. Intraoperative findings showed a ruptured Acom aneurysm and two unruptured true Pcom aneurysms. One true Pcom aneurysm originated from the bifurcation of the premammillary artery and had already been diagnosed preoperatively. The other small true Pcom aneurysm was located at the non-branching site. Both aneurysms were successfully clipped. Careful preoperative diagnosis and intraoperative investigation are important to detect small aneurysms, as in this case.