Introduction: The aim of this article is to report on our experience in using a low field intraoperative MRI (iMRI) system in glioma surgery and to summarize the hitherto use and benefits of iMRI in glioma surgery.
Patients and methods: Between July 2004 and May 2009, a total of 103 patients harboring gliomas underwent tumor resection with the use of a mobile low field iMRI in our institution. Surgeries were performed as standard micro-neurosurgical procedures using regular instrumentarium. All patients underwent early postoperative high field MRI to determine the extent of resection. Adjuvant treatment was conducted according to histopathological grading and standard of care.
Results: All tumors could be reliably visualized on intraoperative imaging. Intraoperative imaging revealed residual tumor tissue in 51 patients (49.5%), leading to further tumor resection in 31 patients (30.1%). Extended resection did not translate into a higher rate of neurological deficits. When analyzing survival of patients with glioblastoma, patients undergoing complete tumor resection did significantly better than patients with residual tumor (50% survival rate at 57.8 weeks vs. 33.8 weeks, log rank test p=0.003), while younger age did not influence survival (p=0.12).
Conclusion: Low field iMRI is a helpful tool in modern neurosurgery and facilitates brain tumor resection to a maximum safe extent. Its use translates into a better prognosis for these patients with devastating tumors. Future studies covering the use of iMRI will need to be conducted in a prospective, randomized fashion to prove the true benefit of iMRI in glioma surgery.