A magnetic resonance imaging technique to evaluate tumor-brain adhesion in meningioma: brain-surface motion imaging.

OBJECTIVE: We examined the effectiveness of a newly developed magnetic resonance imaging (MRI) technique, brain surface motion imaging (BSMI), in the preoperative evaluation of tumor-brain adhesion in meningioma surgery.

METHODS: Cine phase-contrast MRI was used to measure cerebrospinal fluid (CSF) pulsations and heart rates at 2 different time points to create a subtraction image in meningioma patients who underwent BSMI. With no tumor-brain adhesion, a gap was observed in the tumor-brain movements, resulting in an outline of the tumor in BSMI. If adhesion was evident, no outline was observed. Cases were evaluated as exact if the presence or absence of edema in T2-weighted MRI, BSMI findings, and intraoperative findings all matched; as effected when only BSMI findings and intraoperative images matched; and as false when BSMI findings and intraoperative findings did not match.

RESULTS: BSMI judged 27 patients as adhesion (+) and 33 as adhesion (-), whereas surgical findings evaluated 22 as adhesion (+) and 38 as adhesion (-). The sensitivity and specificity were both high, at 95.5% and 84.2%, respectively. Forty-one of 60 patients were evaluated as exact, 12 as effected, and 7 as false. World Health Organization tumor grade assessment of effected subjects included 16.7% in grade 1 and 36.4% in grade 2.

CONCLUSIONS: BSMI was shown to be effective in evaluating adhesion between the meningioma and the brain, allowing safe and effective removal planning to be carried out preoperatively.