Moyamoya - leptomeningeal ivy sign, pre and post-treatment

Case contributed by Dr Walter L. Champion


Presented with left-sided hemiparesis and was referred for further evaluation.

Patient Data

Age: 4 years
Gender: Female
  • FLAIR: diffuse leptomeningeal FLAIR hyperintensity
  • MRA: absence of flow in both internal carotid arteries from the skull base to the cavernous sinuses

Three years status post bilateral pial synagiosis

  • FLAIR: minimal residual leptomeningeal FLAIR hyperintensity 

Case Discussion

The patient initially presented with a stroke which was visualized on CT and confirmed on MRI. The MRI also demonstrated extensive leptomeningeal FLAIR hyperintensity. This finding alone lends itself to a wide differential diagnosis 3. In conjunction with the occlusive MRA findings (which were confirmed with catheter angiography), the FLAIR signal abnormalities are most consistent with the "ivy sign" of Moyamoya. This sign has been attributed to slow flow through pial collateral arteries4. Although, more recently, it has been concluded to result from dilated pial vasculature compensating for decreased perfusion pressure 1 In this case, the FLAIR signal abnormality nearly completely resolves after surgery.

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Case information

rID: 39717
Published: 17th Sep 2015
Last edited: 14th Sep 2019
Inclusion in quiz mode: Included

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