Skull base reconstruction after anterior craniofacial resection

Ketcham popularized the craniofacial resection for tumors of the paranasal sinuses involving the anterior skull base. His pioneering experience fostered the work of many others, leading to surgical removal of tumors with intracranial extension. Many technical advances were gradually introduced but without changing the basic concept of block resection. An unnatural communication between intra- and extracranial spaces is the result of such operations, irrespective of the technique used. The repair of a skull base defect has been the object of heated discussions, and many variations have been proposed. The simple reconstruction of Ketcham has been followed by more sophisticated procedures using galeal-pericranial flaps, free flaps with microvascular anastomosis and bony or alloplastic augmentation. Ketcham did not repair the skull base; he used only a split-thickness skin graft placed on the dura. He had many complications but never brain herniation. The reasons advanced by those who support sophisticated repairs are, to supply adequate structural support for the intracranial contents, thereby preventing brain herniation: avoid intracranial infections; diminish the risk of CSF leakage; and avoid pneuinocephalus. Between 1987 and 1999, 200 patients underwent an anterior craniofacial resection for malignant ethmoid tumors at the Istituto Nazionale per lo Studio e la Cura dei Tumor of Milan, Italy. We perform a coronal skin and galea incision, by raising the skin and galea and preparing a rectangular anteriorly pedicled pericranial flap. The frontal craniotomy measures 7x3 cm. Its inferior edge is 1 cm above the orbital roofs, thus sparing supraorbital vessels and nerves. After the resection of the tumor, our skull base reconstruction is very simple. We make 6 little holes on the bony edges of the skull base defect, 2 on the residual sphenoid roof and 4 laterally on the orbit roofs. The pericranial flap is brought back and into the cranium and fixed with 6 sutures to these holes. We do not use bone or alloplastic augmentation. When an orbital clearance or a total maxillectomy is performed, we use the temporal muscle (26 cases) or a free flap (6 cases) for coverage. We never had brain herniation; CSF leak occured in 18 patients, none of whom required reoperation.