Our Summary

Moyamoya disease (MMD) is a condition where the main artery in the brain progressively gets blocked, resulting in the formation of smaller, weaker vessels. This can lead to brain bleeds or lack of oxygen in the brain. The most effective treatment for MMD is a direct vascular bypass, where a healthy vessel is grafted to bypass the blocked artery.

However, patients with MMD have unstable brain artery conditions and poor blood flow. So, during the bypass surgery, factors like the patient’s response to anesthesia can affect the blood flow in their brain. If the brain tissue gets too much blood flow, it could lead to a condition called hyperperfusion syndrome. This can cause neurological problems and even brain bleeds in severe cases. If the balance of blood flow is disturbed, it can lead to brain tissue death.

Additionally, the vessels used in the bypass are prone to blockage or shrinkage when blood resistance increases. Even pressing on the side of the head can affect these vessels. Because a vessel from the scalp is used in the surgery, the scalp can lack blood flow and may develop tissue death and infection.

These complications from MMD surgery are complex and not well understood. No comprehensive studies on complications after bypass surgery in MMD have been carried out so far. This paper thus reviews and summarizes the existing literature on the complications of direct bypass in MMD.

FAQs

  1. What is Moyamoya disease (MMD) and how is it treated?
  2. What complications can arise from a vascular bypass surgery for MMD?
  3. What is hyperperfusion syndrome and how does it relate to MMD surgery?

Doctor’s Tip

To reduce the risk of complications after vascular bypass surgery for Moyamoya disease, it is important for patients to closely follow their doctor’s post-operative instructions. This may include taking prescribed medications, attending follow-up appointments, and avoiding activities that could put strain on the bypassed vessels. It is also crucial for patients to communicate any new or worsening symptoms to their healthcare provider promptly. By staying informed and actively participating in their care, patients can help ensure a successful outcome after vascular bypass surgery.

Suitable For

Patients with Moyamoya disease who have progressive blockage in the main artery of the brain are typically recommended vascular bypass surgery. This procedure involves grafting a healthy vessel to bypass the blocked artery in order to improve blood flow to the brain. However, patients with MMD have unstable brain artery conditions and poor blood flow, which can lead to complications such as hyperperfusion syndrome, neurological problems, brain bleeds, and tissue death. The vessels used in the bypass surgery are also prone to blockage or shrinkage, and the scalp may lack blood flow and develop tissue death and infection. Complications from MMD surgery are complex and not well understood, and more research is needed to better understand and manage these risks.

Timeline

Before the vascular bypass surgery, a patient with Moyamoya disease may experience symptoms such as headaches, seizures, transient ischemic attacks (mini-strokes), and cognitive decline. These symptoms are a result of the decreased blood flow to the brain due to the blocked artery.

During the vascular bypass surgery, the patient will be put under anesthesia and the surgeon will graft a healthy vessel to bypass the blocked artery in the brain. Factors such as the patient’s response to anesthesia and the balance of blood flow in the brain can affect the outcome of the surgery.

After the vascular bypass surgery, the patient may experience complications such as hyperperfusion syndrome, where there is an excess of blood flow to the brain leading to neurological problems or brain bleeds. The vessels used in the bypass surgery are also at risk of blockage or shrinkage, which can lead to further complications.

Overall, the timeline of a patient with Moyamoya disease before and after vascular bypass surgery involves experiencing symptoms related to decreased blood flow to the brain, undergoing surgery to bypass the blocked artery, and potentially facing complications from the surgery such as hyperperfusion syndrome or vessel blockage.

What to Ask Your Doctor

  1. What are the potential risks and complications associated with vascular bypass surgery for Moyamoya disease?

  2. How likely am I to experience complications such as hyperperfusion syndrome or vessel blockage/shrinkage after the surgery?

  3. How will my anesthesia be managed during the surgery to ensure optimal blood flow to the brain?

  4. What measures will be taken to prevent infections and promote healing in the scalp area where the vessel is harvested from?

  5. Are there any specific post-operative care instructions I should follow to reduce the risk of complications?

  6. How often will I need follow-up appointments after the surgery to monitor for any potential complications?

  7. Are there any lifestyle changes or medications I should consider to reduce the risk of complications post-surgery?

  8. What are the signs and symptoms I should watch out for that may indicate a complication or need for immediate medical attention?

  9. Are there any alternative treatment options or additional procedures that may be recommended to reduce the risk of complications or improve outcomes?

  10. Can you provide me with more information on the success rates and long-term outcomes of vascular bypass surgery for Moyamoya disease in patients who have experienced complications?

Reference

Authors: Yu J, Shi L, Guo Y, Xu B, Xu K. Journal: Int J Med Sci. 2016 Jul 5;13(8):578-87. doi: 10.7150/ijms.15390. eCollection 2016. PMID: 27499690