[The subcranial approach for tumors involving the anterior skull base]

The technical approach for anterior skull base tumors has progressed considerably during the last decade. In the classical combined craniofacial resection (CFR) technique, anterior skull base lesions have been approached through bi-frontal craniotomy coupled with Weber-Ferguson and related modifications incisions. The purpose of this work is to present our experience with the subcranial approach for treatment of anterior skull base tumors. During the years 1994-2002, 64 patients underwent 72 procedures of anterior skull base tumor resection via the subcranial approach. The ages of the patients ranged from 2 to 81 years (mean 42 years). Twenty-nine cases involved malignant tumors (40%), and 43 cases involved benign tumors (60%). The most common benign pathology was meningioma (n = 12) and the most common malignant tumor was squamous cell carcinoma (n = 8). The principle skull base reconstruction procedure was performed using a multi-layered fascia: limited defects of the dura were reconstructed with the use of temporalis fascia, whereas reconstruction of large dural defects was performed using a multi-layered fascia lata sheath. Reconstruction of significant bony defects was achieved by utilizing a split calvarial bone graft, posterior sinus wall, or titanium mash covered with pericranial flap. Postoperative follow-up (26 months in average) revealed that 76% of the patients are without evidence of disease, 14% are alive with disease, 3% died of their diseases and 7% died of unrelated causes. Twenty-seven patients (44%) have suffered from anosmia following the operation. The rate of severe complications was 5.6%, and included meningitis (n = 2), cerebrospinal fluid rhinorrhea (n = 1) and tension pneumocephalus (n = 1). We conclude that the extirpation of anterior skull base tumors via the subcranial approach is simple, reproducible and reliable, and is associated with reasonable complication rates.