Galeo-pericranial flaps in the forehead: a study of blood supply and volumes.

Despite their extensive use in anterior cranial base reconstruction, very little is understood about the blood supply of galeo-pericranial flaps derived from the forehead region. The goal of this study was to define the extent of the reliable axial blood supply and to determine the volumes of these flaps. The blood supply to anteriorly based galeo-pericranial flaps depends entirely upon the deep branches and a variable component of the superficial branches of the supraorbital and the supratrochlear vessels. The axial component of the blood supply to these flaps is 20-70 mm. The extent of "random' pattern blood supply distal to this could not be adequately assessed. The volumes of various galeo-pericranial flaps range from 3 to 48 cc. The well vascularized proximal portions of galeo-pericranial flaps may well serve the reconstructive needs of the anterior cranial base. Use of more distal portions of these flaps should be undertaken with caution. Some increase in bulk and vascularity may be achieved if the pericranial and the galeal-frontalis myofascial flaps are harvested as a single unit, the composite galeal-frontalis-pericranial flap. Due to the vascular and volume limitations of galeo-pericranial flaps, consideration should be given to the use of microvascular free tissue transfers in instances where large soft tissue defects and a large "dead space' occur.