We present 2 patients in whom basal interhemispheric (BIH) approaches were applied to surgically address anterior communicating artery aneurysms (AcomAn) after initial surgery via pterional approaches that resulted in incomplete clipping. In both patients, the initial clips were successfully removed with use of vario clip appliers followed by complete neck clipping. The first case was a 55-year-old man with subarachnoid hemorrhage (SAH) who arrived in poor cardiopulmonary condition. Angiographic evidence of extravasation of the contrast media led us to immediately surgically intervene via the dominant side of the anterior cerebral artery. However, complete neck clipping was abandoned due to marked brain swelling, and only aneurysm dome clipping was achieved. Thirty-eight days later, a second surgery was performed using the BIH approach. The second case was a 66-year-old woman with SAH caused by ruptured AcomAn associated with the median artery of the corpus callosum (MACC). A residual neck remnant grew gradually. After failed coil embolization, she had a second surgical intervention via the BIH approach 18 months after the initial surgery. Previous clips were removed in both patients and the coil was also removed in the second one. The BIH approach provides a wider surgical view and working space. We report technical tips to remove previously placed clips via different surgical approaches.
