Symptoms of Moyamoya Disease: What You Need to Know

Moyamoya disease is a rare, progressive cerebrovascular disorder that affects the blood vessels in the brain. Over time, the internal carotid arteries at the base of the brain become narrowed or blocked, reducing blood flow and increasing the risk of stroke and other neurological complications. Recognizing the symptoms early can significantly improve outcomes through timely diagnosis and treatment.

Common Signs and Symptoms of Moyamoya Disease

One of the earliest and most frequently reported symptoms of moyamoya disease is headaches and dizziness. These often occur due to reduced cerebral perfusion—meaning the brain isn't receiving enough oxygen-rich blood because of the narrowing of the internal carotid artery. Patients may describe persistent headaches accompanied by lightheadedness, especially during physical activity or stress.

Cognitive Changes and Memory Impairment

Chronic insufficient blood supply to the brain can lead to noticeable declines in cognitive function. Many individuals experience memory loss, difficulty concentrating, and slower mental processing. These changes are sometimes mistaken for normal aging or early dementia, but in younger patients, they may actually be warning signs of an underlying vascular condition like moyamoya disease.

Transient Ischemic Attacks (TIAs)

A major red flag for moyamoya disease is experiencing transient ischemic attacks—often referred to as "mini-strokes." During a TIA, patients may suddenly develop symptoms such as slurred speech, inability to speak, weakness or paralysis on one side of the body, facial drooping, or confusion. These episodes typically last only a few minutes to hours but should never be ignored, as they can precede a full-blown stroke.

In some cases, TIAs may also be associated with hydrocephalus-like symptoms, including balance issues, nausea, or vision problems, depending on which areas of the brain are affected by the compromised blood flow.

Seizures and Neurological Episodes

Seizure activity is another significant symptom linked to moyamoya disease. Seizures can range from mild, barely noticeable episodes to full convulsions, often triggered by abnormal electrical activity in brain regions deprived of adequate blood flow. Children diagnosed with moyamoya are particularly prone to seizures, making it a critical indicator in pediatric cases.

In advanced stages, repeated strokes or chronic ischemia may lead to more severe neurological deficits, including motor dysfunction, speech impairments, and developmental delays in children. Early imaging studies such as MRI or angiography are essential for confirming the diagnosis and planning appropriate interventions.

If you or a loved one experiences recurring headaches, unexplained neurological episodes, or sudden cognitive changes, consulting a neurologist is crucial. With proper medical management—including medications, surgical revascularization, and lifestyle adjustments—many patients with moyamoya disease can lead active, fulfilling lives.