Moyamoya Disease and Syndrome in Adults: A Report of Four Cases.

Moyamoya disease and syndrome is a rare angiogenic disorder characterized by progressive narrowing of the distal internal carotid artery and proximal segments of the middle and anterior cerebral arteries, leading to the formation of replacement vessels to compensate for reduced cerebral perfusion downstream of the stenosis. Its etiology remains poorly understood, and its most serious consequences are ischemic or hemorrhagic stroke. It may be primary or secondary. We present four cases of Moyamoya disease and syndrome, including three women and one man, with ages of 42, 44, 46, and 45 years, respectively. Three patients presented with ischemic stroke, and one patient experienced multiple ischemic and hemorrhagic cerebrovascular events. All four had undergone emergency cerebral CT and/or MRI, but the diagnosis was made by CT angiography and cerebral digital subtraction angiography. All four patients received medical treatment with calcium channel blockers and antiplatelet agents, with rehabilitation, and none underwent revascularization. The etiological investigation revealed Sjögren's syndrome in one patient, hyperthyroidism in another, and no abnormalities in the remaining cases. Through these four observations, we discuss the clinical presentations, diagnosis, and therapeutic features of this rare condition.