Minimally invasive superficial temporal artery to middle cerebral artery bypass through an enlarged bur hole: the use of computed tomography angiography neuronavigation in surgical planning.

The authors describe their minimally invasive technique for performing a superficial temporal artery (STA) to middle cerebral artery (MCA) bypass, which relies on an enlarged bur hole (2-2.5 cm) rather than the standard craniotomy. They perform this procedure in a minimally invasive fashion, using CT angiography for intraoperative neuronavigation as well as for preoperative identification of the donor and recipient vessels and planning of bur hole location. They present 2 cases in which this procedure was used, including one involving a patient with multivessel occlusive disease and significant cerebrovascular hemodynamic compromise in whom they performed the procedure using only local anesthetic and propofol sedation in order to minimize the risk of hypotension associated with the use of general anesthetic agents. A comprehensive literature search revealed no previously published case of an extracranial-intracranial arterial bypass procedure performed in an awake patient. The authors have adopted the described minimally invasive method for all STA-MCA bypass procedures. The awake setting, however, is reserved for specific indications, primarily patients with severe moyamoya disease, in whom ventilator-related hypocarbia can result in intraoperative ischemia, or patients with multivessel occlusive disease and significant cerebral hemodynamic compromise, in whom general anesthesia-related hypotension can lead to intraoperative ischemia.