Encephaloduroarteriosynangiosis (EDAS) is the most commonly used indirect revascularisation surgery for moyamoya disease or syndrome, which provides a way to bypass an occluded internal carotid artery and circle of Willis without having to perform a direct surgical anastomosis.
It involves dissection of superficial temporal artery branches with surrounding galea, creating a craniotomy and durotomy, and then suturing the galeal cuff to the durotomy edges so that the artery lies on the pial surface of the brain. Revascularisation occurs as a result of angiogenesis driven by local hypoperfusion and ischaemia 1,2. The deep temporal artery is the main arterial supply.
See also
encephaloduroarteriomyosynangiosis (EDAMS): indirect revascularisation using the temporalis muscle, dura, and superficial temporal artery
encephalomyosynangiosis (EMS): indirect revascularisation using the temporalis muscle alone
superficial temporal artery to middle cerebral artery (STA-MCA) bypass: direct anastomosis