Frameless stereotactic localization in cranial base surgery.

Mastery of the three-dimensional anatomic relationships of the cranial base/paranasal sinuses is required to reduce the incidence of iatrogenic surgical complications, facilitate complete tumor extirpation, and enhance functional outcomes. Real-time intraoperative localization technology is one method available to assist the cranial base surgeon. We report our institutional experience with the StealthStationtrade mark treatment guidance platform. Eighty-eight consecutive patients with pathology of the cranial base/paranasal sinuses were operated on with the aid of real-time frameless stereotactic localization. Preoperative image data sets were acquired with either CT or MRI scans. Patient demographics, accuracy of the data sets, surgical approaches, pathology, complications, and further applications of this technology are presented. Procedures were performed on 47 women and 41 men ranging in age from 6 to 85 years. In these 88 procedures, 44 MRI and 44 CT scans with a mean accuracy of 1.57 and 1.23 mm, respectively, were used. Approaches to the cranial base included midface degloving (25), endoscopic (23), craniofacial (13), maxillectomy (12), rhinotomy without maxillectomy (5), transoral (5), pterional (2), transcondylar (1), and transcervical (2). Indications for surgery included severe inflammatory disease of the paranasal sinuses with epidural or subdoral abscess, or both (7), cerebrospinal fluid fistula or encephalocele, or both (11), and 40 benign and 30 malignant tumors. Complications occurred in 10 of 88 patients (11%). Real-time intraoperative localization can be applied to cranial base surgery in a variety of scenarios. The instantaneous transfer of imaging data to the surgical field is useful in localizing pathology, enhancing operative safety, and reducing morbidity, thereby improving outcomes. This technology will certainly play an integral role in minimizing complications and improving surgical outcomes as cranial base surgery moves into the next millennium.