Computer‐aided detection of brain tumor invasion using multiparametric MRI

Abstract

Purpose To determine the potential of using a computer‐aided detection method to intelligently distinguish peritumoral edema alone from peritumor edema consisting of tumor using a combination of high‐resolution morphological and physiological magnetic resonance imaging (MRI) techniques available on most clinical MRI scanners. Materials and Methods This retrospective study consisted of patients with two types of primary brain tumors: meningiomas (n = 7) and glioblastomas (n = 11). Meningiomas are typically benign and have a clear delineation of tumor and edema. Glioblastomas are known to invade outside the contrast‐enhancing area. Four classifiers of differing designs were trained using morphological, diffusion‐weighted, and perfusion‐weighted features derived from MRI to discriminate tumor and edema, tested on edematous regions surrounding tumors, and assessed for their ability to detect nonenhancing tumor invasion. Results The four classifiers provided similar measures of accuracy when applied to the training and testing data. Each classifier was able to identify areas of nonenhancing tumor invasion supported with adjunct images or follow‐up studies. Conclusion The combination of features derived from morphological and physiological imaging techniques contains the information necessary for computer‐aided detection of tumor invasion and allows for the identification of tumor invasion not previously visualized on morphological, diffusion‐weighted, and perfusion‐weighted images and maps. Further validation of this approach requires obtaining spatially coregistered tissue samples in a study with a larger sample size. J. Magn. Reson. Imaging 2009;30:481–489.