Pericranial healing and the temporalis myo-osseous flap in the rabbit model

The purpose of this animal study was to determine the rate of revascularization of a temporalis myo-osseous (TMO) flap after pericranial elevation. In 24 rabbits, the right pericranium was raised in entirety through a bicoronal flap at the first operation. The pericranium was then reapproximated in situ. The pericranium was allowed to heal for 1 to 28 days before the second operation. At the second operation, through the same bicoronal flap, right and left temporalis myo-osseous flaps were raised. The left temporalis myo-osseous flap served as a control. Revascularization and viability of the temporalis myo-osseous flaps were studied by using technetium bone scans, india ink injection studies, and histologic study. Results demonstrated that 4 days following pericranial elevation, the temporalis myo-osseous flap is viable and revascularized by the pericranium. Immediate bone scanning and india ink injection showed patent pericranial circulation to the osseous portion of the temporalis myo-osseous flap at 4 days. Histologic study confirmed the viability of the temporalis myo-osseous flap. In conclusion, after pericranial elevation, pericranial healing and revascularization were complete at 4 days. This allowed a viable temporalis myo-osseous flap to be raised successfully at this time.