Refinements Using Free-Tissue Transfer for Complex Cranial Base Reconstruction

Abstract

Resection of skull base tumors may sometimes result in massive extirpation defects that are not amenable to local tissue closure. Closure of large basicranial defects can be performed with either a myocutaneous, a deepithelialized myocutaneous, or a simple muscle free flap designed from the ample rectus abdominis vascular territory. This free-tissue donor site has abundant and reliable well-vascularized tissue that can easily be customized to seal these tenuous areas. The rectus abdominis muscle and its vascularized territory were used in 18 of 19 consecutive patients at our center to close basicranial ablation defects. Of these, 6 were rectus abdominis muscle flaps, 5 were myocutaneous rectus abdominis flaps, and 7 were deepithelialized rectus abdominis muscle flaps. All free flaps survived. The intracranial space was sealed successfully in all but one patient. This patient underwent reconstruction with a muscle free flap and had a postoperative cerebrospinal fluid leak. This complication could have been avoided by using a deepithelialized myocutaneous flap to obliterate the central dead space with the vascularized subcutaneous fat. Two patients experienced minor wound infections, and one had a subdural abscess that was fully contained by a free flap placed over the duraplasty. One patient had a donor-site hernia. There was no incidence of meningitis. Knowledge of the anatomy of the vascular territory of the deep inferior epigastric vessels can be used judiciously to secure three-dimensional reconstruction of the skull base. The donor site supplies ample tissue for reconstruction and allows individual tailoring for obliteration of geometrically complex extirpation defects in and around the cranial base without the need to reposition the patient.