Introduction

Moyamoya disease (MMD) is a rare cause of cerebral vascular ischemia, which is radiologically featured as progressive stenosis of the distal part of the internal carotid artery and the formation of capillary collaterals (1). It can affect any age, children and adults, while ischemic manifestations are more common in pediatric cases, whereas hemorrhagic cases are more common in adults. Diagnosis relies on imaging techniques, which include CT, MRI and angiography (2). The disease can progress from unilateral to bilateral involvement, with specific clinical and genetic factors potentially influencing this progression (3). Intracranial haemorrhage is a significant concern, with about half of the adult-onset MMD patients experiencing it. Cerebral ischemia is the most common manifestation, affecting 73.9% of elderly patients along with speech and cognitive impairment (4,5). Cognitive dysfunction is a significant issue in adult MMD patients, particularly affecting those with difficulty in social independence. A broad range of cognitive functions can be disrupted, including basic abilities and frontal lobe function (6). While the optimal treatment strategy remains debated, personalized selection based on patient characteristics and disease severity is crucial for balancing perioperative risks and long-term benefits in MMD management. MMD treatment primarily involves cerebral revascularization through direct or indirect bypass procedures. Direct bypass, such as superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis, provides higher revascularization rates and potentially better clinical outcomes (7).  Herein, we will discuss a 20-year-old male, non-smoker and non-alcohol consumer with a diagnosis of MMD, which is a rare chronic cause of stroke.