Combined direct and indirect superficial temporal artery-to-middle cerebral artery bypass with a hinged bone flap: how I do it

Superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass is a critical treatment for moyamoya disease and steno-occlusive cerebrovascular disease. Combined bypass (direct + indirect) optimizes the chance of durable flow augmentation but can complicate wound closure from tissue disruption.We describe our technique for combined direct and indirect (encephaloduromyosynangiosis; EDAMS) STA-MCA bypass using a hinged bone flap. In addition to a direct bypass, EDAMS provides multiple sources for indirect revascularization. The hinged bone flap gently approximates the muscle and pia for secondary vascular ingrowth.Combined STA-MCA bypass with a hinged bone flap safely maximizes revascularization potential.