Two Cases of Twig-like Middle Cerebral Artery Detected via Brain Dock: Management of Asymptomatic Cases

Abstract

Twig-like middle cerebral artery (T-MCA) is characterized by a unilateral stenotic lesion of the middle cerebral artery (MCA), associated with a plexiform abnormal vascular network that should be differentiated from unilateral moyamoya angiopathy. Here, we present two cases of T-MCA found via brain dock and discuss the management of asymptomatic cases based on a literature review. Both cases were initially diagnosed as unilateral moyamoya disease but were identified as T-MCA based on cerebral angiography. Case 1 involved a 40-year-old woman. Cerebral blood flow (CBF) at rest was normal; however, the Diamox stress test showed a slight decrease in cerebral reserve capacity (stage 1) on the same side as the MCA area. Case 2 involved a 38-year-old man with normal CBF at rest. A literature review suggested that 30% of asymptomatic T-MCA cases were accompanied by hemorrhagic or ischemic cerebral stroke. Therefore, stroke risk factors should be prevented or managed in asymptomatic patients with T-MCA. Furthermore, regular follow-up imaging is required.