Indirect Revascularization

Indirect Revascularization

There are various indirect surgical methods used for providing more blood flow to the brains of moyamoya patients.

EDAS (encephalo-duro-arterio-synangiosis) uses a branch of the superficial temporal artery which is laid directly on the surface of the brain without doing a direct anastomosis. The expectation is that it will eventually grow new arteries into the brain and therefore provide more blood flow. This surgery is done at Stanford only when a direct bypass graft is not feasible. In our experience, children tend to have better results with this procedure than adults. Once used for an indirect bypass, the STA branch cannot be used again for direct bypass, even if the indirect bypass is not successful. It usually requires at least 3-6 months for new blood supply to develop from this procedure.

EMS (encephalo-myo-synangiosis) is another indirect bypass operation. The temporalis muscle, which is in the temple region of the forehead, is dissected. Then, through an opening in the skull, the muscle is placed on the surface of the brain. Like the EDAS, 3-6 months are required for a new blood supply to develop from the transposed muscle.