Reconstruction of skull base defects.

Skull base defects are classified into three regions based on the anatomic location and growth pattern of the tumors. The goals of reconstruction are based on the necessity of obtaining a watertight seal between the cranial contents and the aerodigestive tract, thereby avoiding any communication, which could result in ascending meningitis. Pedicled flap options have largely been replaced by free tissue transfers, with the exception of small Zone I defects that can still be safely reconstructed with local pedicle flaps. The rectus abdominis free muscle flap has become the workhorse of skull base reconstruction, resulting in a decrease in the complication rate following these procedures. Various other factors have significantly improved the prognosis of patients who require tumor ablation involving the skull base.