Moyamoya Disease
Moyamoya disease is a rare cerebrovascular condition causing stroke risk. One Brain and Spine's Melbourne neurosurgeons are experts in bypass surgery for moyamoya.
What is Moyamoya Disease?
Moyamoya disease is a rare condition that affects the blood vessels in the brain. Over time, the main arteries at the base of the brain become narrowed or blocked. As this happens, the brain tries to compensate by forming a network of small, fragile blood vessels to maintain blood flow. On brain scans, these tiny vessels have a hazy appearance that looks like a “puff of smoke” – the meaning of moyamoya in Japanese.
Moyamoya disease can occur in both children and adults, but it often presents differently depending on age. In children, it usually causes reduced blood flow to the brain, leading to transient ischaemic attacks (TIAs) or strokes. In adults, it can cause either reduced blood flow or bleeding in the brain due to rupture of the fragile vessels. Without treatment, the condition typically progresses over time and carries a significant risk of recurrent stroke and long-term neurological problems.
Surgical revascularisation is the mainstay of treatment and is effective in improving blood flow to the brain. This includes cerebral bypass procedures. One Brain and Spine's neurosurgeons are among the few in Australia trained and experienced in this specialised technique.
What Causes Moyamoya Disease?
The exact cause is not fully understood, but several factors are linked.
Genetic factors appear to play an important role. Moyamoya is more common in people of East Asian background (Japanese, Korean, and Chinese populations), and some cases run in families. Variations in the RNF213 gene have been associated with the condition.
In some cases, the same pattern of blood vessel narrowing occurs as part of another medical condition. This is referred to as moyamoya syndrome rather than moyamoya disease. Associated conditions include sickle cell disease, Down syndrome, neurofibromatosis type 1, prior cranial radiation, and certain thyroid disorders.
Symptoms of Moyamoya Disease
Ischaemic Symptoms (Stroke and TIA)
Reduced blood flow through the narrowed blood vessels can cause a stroke or TIA. This may result in the sudden onset of weakness, speech difficulty, facial drooping, visual changes, or sensory loss. Recurrent ischaemic events can lead to progressive cognitive decline and disability.
Haemorrhagic Stroke
In adults, rupture of the fragile moyamoya collateral vessels can cause bleeding in the brain. This may result in a sudden severe headache, loss of consciousness, and a focal neurological deficit. This presentation is more common in adult-onset disease than in children.
Headache
Recurrent headaches are common and may relate to cerebral ischaemia or stretching of the abnormal collateral vessels.
Cognitive Decline
Repeated TIAs and ischaemic events can lead to progressive cognitive
How is Moyamoya Disease Diagnosed?
Moyamoya disease is diagnosed using specialised brain imaging.
- Cerebral angiography (also called digital subtraction angiography or DSA) – the most accurate test and shows the characteristic narrowing of the arteries along with the abnormal “puff of smoke” vessels.
- MRI and MR angiography (MRA) – scans are commonly used to identify areas of the brain affected by reduced blood flow and to visualise the abnormal vessels.
- CT or MRI perfusion scans – assess how well blood is reaching different areas of the brain and help identify regions at risk
Treatment of Moyamoya Disease
Medical treatment alone is usually not enough to stop the progression of moyamoya disease. The main goal of treatment is to improve blood flow to the brain and reduce the risk of future strokes.
Medical Management
Medications such as aspirin are often used to reduce the risk of blood clots, but they do not treat the underlying problem of narrowed arteries. It is also important to manage any associated medical conditions.
Direct Revascularisation — STA-MCA Bypass
Surgical treatment involves creating new pathways for blood to reach the brain, a process known as revascularisation. In direct bypass surgery, a blood vessel from the scalp is connected directly to a blood vessel on the surface of the brain. This provides an immediate new source of blood flow.
Indirect Revascularisation
In indirect procedures, tissue containing blood vessels is placed onto the brain surface, encouraging new vessels to grow over time. This approach is often used in children.
In some cases, both direct and indirect techniques are combined to achieve the best outcome.
FAQs
Why Choose One Brain and Spine for Moyamoya Disease in Melbourne?
One Brain and Spine is a specialist neurosurgical group practice in Melbourne, bringing together extensive expertise in brain, spinal, and peripheral nerve surgery. Our team has particular strength in cerebrovascular neurosurgery, delivering multidisciplinary care using the latest technology available in Australia. We are committed to providing comprehensive, patient-focused treatment through:
- Specialist cerebrovascular neurosurgeons — internationally fellowship-trained with subspecialty cranial and cerebrovascular surgery expertise
- Advanced technology — including intraoperative navigation, neuromonitoring, and state-of-the-art microsurgical techniques
- Multidisciplinary care — close collaboration with neurologists, neurointerventionalists, and radiation oncologists to ensure optimal outcomes
- Patient-centred approach — compassionate care with clear explanations of your diagnosis and all available treatment options
- All major health funds accepted