Advanced Multiparametric MRI of Multinodular and Vacuolating Neuronal Tumor.

BACKGROUND: Multinodular and Vacuolating Neuronal Tumor of the cerebrum (MVNT) is a rare brain lesion with suggestive imaging features. The aim of our study was to report the largest series of MVNTs so far and to evaluate the utility of advanced multiparametric Magnetic Resonance (MR) techniques. METHODS: This multicenter retrospective study was approved by our institutional research ethics board. From July 2014 to May 2019, two radiologists read in consensus the MR examinations of patients presenting with a lesion suggestive of a MVNT. They analyzed the lesions' MR characteristics on structural images and on advanced multiparametric MR imaging. RESULTS: 64 patients (29 women and 35 men, mean age 44.2+/-15.1 years) from 25 centers were included. Lesions were all hyperintense on FLAIR and T2-WI without post-contrast enhancement. The median relative-Apparent Diffusion Coefficient on Diffusion-weighted imaging was 1.13 [IQR 0.2]. Perfusion- weighted imaging showed no increase in perfusion, with a relative-Cerebral Blood Volume of 1.02 [IQR 0.05] and a relative-Cerebral Blood Flow of 1.01 [IQR 0.08]. MR spectroscopy showed no abnormal peaks. Median follow-up was 2 [IQR 1.2] years, without any changes in size. CONCLUSIONS: A comprehensive characterization protocol including advanced multiparametric MRI sequences showed no imaging patterns suggestive of malignancy in MVNTs. It might be useful to better characterize MVNTs.