Application of intraoperative high-field magnetic resonance imaging in pediatric neurosurgery

Over the past decade, the use of intraoperative MR (iMR) imaging in the pediatric neurosurgical population has become increasingly accepted as an innovative and important neurosurgical tool. The authors summarize their experience using a mobile 1.5-T iMR imaging unit with integrated neuronavigation with the goal of identifying procedures and/or pathologies in which the application of this technology changed the course of surgery or modified the operative strategy.

A database has been prospectively maintained for this patient population. The authors reviewed the hospital charts and imaging results for all patients in the database. This review revealed 105 neurosurgical procedures performed in 98 children (49 male and 49 female) between March 1998 and April 2008. Intradissection (ID) and/or quality assurance images were obtained at the discretion of the surgeon.

The median age at surgery was 12 years (4 months-18 years). One hundred intracranial and 5 spinal procedures were performed; 22 of these procedures were performed for recurrent pathology. Surgical planning scans were obtained for 102 procedures, and neuronavigation was used in 93 patients. The greatest impact of iMR imaging was apparent in the 55 procedures to resect neoplastic lesions; ID scans were obtained in 49 of these procedures. Further surgery was performed in 49% of the procedures during which ID scans had been obtained. A smaller proportion of ID scans in the different cranial pathology groups (5 of 21 epilepsy cases, 4 of 9 vascular cases) resulted in further resections to meet the surgical goal of the surgeon. Two ID scans obtained during 5 procedures for the treatment of spinal disease did not lead to any change in surgery. Postoperative scans did not reveal any acute adverse events. There was 1 intraoperative adverse event in which a Greenberg retractor was inadvertently left on during ID scanning but was removed after the scout scans.

The application of iMR imaging in the pediatric neurosurgical population allows, at minimum, the opportunity to perform less invasive surgical exposures. Its potential is greatest when its high-quality imaging ability is coupled with its superior neuronavigation capabilities, which permits tracking of the extent of resection of intracranial tumors and, to a lesser extent, other lesions during the surgical procedure.