Augmentation of the Patency of an Extracranial-Intracranial Bypass Accompanied by the Occlusion of an Intracranial Stenotic Lesion

We describe a case that showed augmention of the superficial temporal artery [STA] pedicle's patency 15 months after extracranial to intracranial [EC-IC] bypass surgery for a carotid artery occlusion with contralateral intracranial internal carotid artery stenosis. It is rare that meager patency of the STA pedicle in the early postoperative angiogram can be become well augmented with time where most branches of the middle cerebral artery [MCA] are robustly filled with blood from the STA. A 28-year-old woman with a history of a previous left hemispheric stroke presented with slurred speech after several bouts of seizure. Magnetic resonance imaging showed a new infarct on the right hemisphere in addition to an old infarct on the left hemisphere. Carotid angiography revealed stenosis of the right carotid siphon and occlusion of the left carotid artery. The patient underwent EC-IC bypass on the right side. Even though the early postoperative angiogram showed meager filling of MCA with no significant stenotic lesion change, a subsequent angiogram taken 15 months later, demonstrated a widely patent STA pedicle with occlusion of the previous intracranial stenotic lesion. Selected cases with an inaccessible intracranial stenotic lesion can benefit from EC-IC bypass surgery; however, its clear indication should first be established.