Neuronavigation by Intraoperative Ultrasound: During Intracranial Cavernoma Resection

Abstract

Background In this prospective study, the use of a system of ultrasound-integrated neuronavigation was investigated to evaluate the benefits of improving brain shift during cerebral cavernous angioma (CCA) resection. Methods Between June 2000 and June 2005, 26 CCAs of 22 patients underwent microsurgical removal with the guidance of neuronavigation, and a 7-MHz intraoperative ultrasonography (Toshiba, Tosbee SSA 240 A, Tokyo, Japan) at our institution. The preoperative neurologic status and postoperative outcome were recorded. Patients' follow-up monitoring ranged from 6 months to 4 years (mean, 18 mo). Results The computer neuronavigation-calculated registration accuracy ranged between 0.2 and 1.7 mm (mean, 0.5 mm). During resection, brain shift was measured 2 to 4.5 mm (mean, 3.2 mm) in 14 lesions, as verified by neuronavigation. The overall postoperative neurologic outcome was excellent in 21 of the 22 (95.4%) patients. Postoperative magnetic resonance imaging was performed in all cases and showed a total resection of the lesion in 21 patients (95.6%). The resection was subtotal in 1 patient (4.4%). Although there was no mortality, 2 patients (9.1%) had worsening in neurologic status in early postoperative period. Conclusions On the basis of these results, a system of intraopeative ultrasound-integrated neuronavigation is a less expensive and time consuming imaging technique for the surgical treatment of CCAs. The update of a neuronavigation system with both intraoperative ultrasound reliably correct of the brain shift and is reliable intraoperative guidance tool in localization of deep-seated CCAs because it operates in real time.