Will Moyamoya Disease Be Passed on to Children?

Moyamoya disease is a rare, progressive cerebrovascular disorder characterized by the narrowing or blockage of major arteries at the base of the brain. While it is considered a congenital condition—meaning individuals are born with a predisposition to it—the actual risk of inheritance from parent to child remains relatively low. Although no precise genetic transmission rate has been established, research suggests that only a small percentage of cases have a familial link, indicating that genetics may play a role but are not the sole determining factor.

Understanding the Genetic Component

While moyamoya disease can appear in multiple members of the same family, such occurrences are uncommon. When there is a family history of the condition, the likelihood of other relatives developing it increases slightly compared to the general population. However, most diagnosed cases are sporadic, meaning they occur without any known family history. Scientists believe that certain gene mutations—such as those in the RNF213 gene—may contribute to the development of moyamoya, especially in Asian populations where the disease is more prevalent.

Recognizing Early Symptoms in Children

If one family member has been diagnosed with moyamoya disease, parents should remain vigilant for potential signs in their children. Common early symptoms include frequent headaches, dizziness, nausea, vomiting, difficulty speaking, facial drooping, and sudden weakness or clumsiness in limbs—especially during physical activity or hyperventilation. These neurological episodes may be mistaken for migraines or seizures, making accurate diagnosis critical.

Diagnostic Tools for Accurate Detection

Early detection significantly improves long-term outcomes. Non-invasive imaging techniques such as CT angiography (CTA) and magnetic resonance angiography (MRA) are typically used first to evaluate blood flow and identify arterial narrowing in the brain. These scans help detect abnormalities and guide further evaluation.

The Gold Standard: Digital Subtraction Angiography (DSA)

While CTA and MRA provide valuable insights, the definitive diagnostic method for moyamoya disease is digital subtraction angiography (DSA). This invasive procedure offers the most detailed visualization of cerebral blood vessels and is essential for confirming the characteristic "puff-of-smoke" appearance of the collateral vessels that give the disease its name—moyamoya, which means "puff of smoke" in Japanese.

Treatment and Prognosis

Once diagnosed, treatment focuses on restoring adequate blood flow to the brain. The most effective approach for many patients, especially children, is revascularization surgery—commonly known as bypass surgery. This procedure helps prevent future strokes and reduces the frequency of transient ischemic attacks (TIAs). With timely intervention, many patients go on to live healthy, active lives.

In summary, while moyamoya disease has a possible genetic component, the chance of passing it to offspring is low. Families with a history of the condition should monitor for neurological symptoms and seek prompt medical evaluation. Advanced imaging technologies and surgical interventions have greatly improved both diagnosis and outcomes, offering hope and effective management for affected individuals.