The term "cerebrovascular diseases" (CBVDs) refers to a collection of diverse illnesses that impact the brain's whole blood supply. Irregularities and issues with the intracranial vasculature can produce an inadequate flow of oxygenated blood to the brain [1]. It consists of a number of distinct pathologies, including cerebral vascular illnesses (e.g., vascular malformations, aneurysms, etc.), hemorrhagic strokes, transient ischemic attacks (TIAs), and ischemic strokes. One stroke occurs every 45 seconds in the US, where there are approximately 700,000 strokes. Moyamoya is a term of Japanese origin that describes a particular angiographic image of blood vessels at the base of the brain. The image resembles uneven nets and is often compared to a puff of cigarette smoke floating in the air [2]. The bypass of the STA MCA has led to an improvement in the artery wall shear stress (WSS). This indicates a faster rate of blood flow in the distal arteries. More total pressure is observed in the bypass, while the MCA distal branches have lower total pressure. This makes it easier for blood to enter these veins. Low WSS zones are more likely to develop atherosclerosis, which can cause ischemic stroke and transient ischemic attack (TIA) by depriving nearby blood vessel regions of oxygen and nutrients. The term "perfusion-weighted imaging" refers to a group of MRI methods that can provide information on the blood's perfusion of different tissues for comparing pre and post-vasculature hemodynamics.