Intraoperative swelling leading to neurological deterioration: an argument for large craniotomy in awake surgery for glioma resection.

Gliomas are intrinsic brain tumours that are frequently associated with cerebral oedema. As such, keyhole approaches may not be appropriate because if the craniotomy is small, intraoperative cerebral oedema may occur, resulting in cortical compression at the bone edge. This would lead to further neurological deficit, especially if the swollen brain is located in eloquent areas. In awake craniotomy, worsening of such a deficit would mandate premature cessation of surgery and lead to a less than ideal extent of resection. Two such cases of intraoperative brain swelling are described to illustrate this point. The authors suggest doing a larger craniotomy for glioma patients undergoing awake surgery to prevent compression of normal brain at the craniotomy edge and to allow for a more complete resection by providing access to the tumour even if intraoperative swelling does occur.