Moyamoya Disease

1
Moyamoya Disease

• Kana Harada

2
OUTLINE

• Background information
• General Symptoms
• Diagnosis
• Surgical Treatments
• Future
• Conclusion

3
What is Moyamoya Disease??

• MMD specific chronic cerebrovascular occlusive
  disease
• Characterized by stenosis of terminal portion of
  internal carotid artery and main branches.
• 1957 first reported Japanese surgeon

4
Background Information

• MMD is high in east Asia
• Two peaks of age distribution
• Age 5
• Ischemic attacks, seizures, involuntary movements
• Age 40
• Half of adult patients with MMD develop
  intracranial bleeding
• More frequent in females than males

5
General symptoms

• Cerebral blood flow (CBF) is significantly lower
  in Moyamoya patients
• Distribution of CBF shows a dominant posterior
  distribution
• Dominant anterior territory distribution found in
  people without the disease.

6
Diagnosis of MMD

• Cerebral/Carotid Angiogram
• MRA
• MRI
• CT scan

7
Cerebral/Carotid Angiogram

• Cerebral Angiogram
• show condition of blood vessels of brain
• Carotid angiography
• study caliber of carotid artery
• stenosis which can cause an increased risk of
  stroke.

8
MRA

•  Preoperative and postoperative MRA of 40 year
  old man with left hemipares
• Useful for diagnosis
• Non-invasive methods that can be repeated after
  surgery.

9
MRI

• Visualize changes in narrowing of vessels of
  circle of Willis and areas of previous stroke
• More sensitive than CT, with use of diffusion and
  perfusion
• Allow identification of early ischemic areas
• Visualization of Moyamoya vessels themselves

10
CT Scan

• Obtain many images from different angles, then
  join them together to show cross-section
• CT scanning provides more detailed information on
  head injuries, tumors, and brain diseases

11
Surgical Treatments

• Surgical procedures for MMD classified into 3
  categories
• direct bypass, indirect bypass, and combined
• Surgical revascularization
• Most successful therapy to improve cerebral
  hemodynamics
• Especially direct
• Reduce risk of subsequent stroke
• No new strokes, no new ischemic lesions

12
Before and After Operation
CT scan low ? high blood flow in both hemispheres
13

• 35-year-old woman with Bilateral MMD, greater on
  right
• (A) MRI shows watershed distribution infarcts in
  left hemisphere
• (B) Left carotid angiogram revealed poor filling
  above ICA
• (C) Angiography showed excellent filling of MCA
  vessels
• (D) After surgery no further ischemic symptoms

14
Future

• Genetic analysis of MMD might help determine
  pathogenesis of MMD in near future.
• If relevant genes could be identified, we might
  be able to develop novel gene therapies and
  prevent occurrence of MMD in patients who are
  genetically susceptible.
• Further follow-up studies are needed to
  understand natural course of asymptomatic MMD.

15
Conclusion

• Background information
• General Symptoms
• Many types of diagnosis
• Surgical revascularization
• Future study