Assessment of neuronal tract fibers using three-dimensional anisotropy contrast imaging in patients with infratentorial brain tumors

Abstract

The purpose of this study was to evaluate neuronal tracts in patients with infratentorial brain tumors using three-dimensional anisotropy contrast (3DAC) imaging technique. Twenty-two patients with infratentorial tumors underwent echo-planar diffusion-weighted imaging (DWI). Gray scale DWIs in each of the three orthogonal diffusion gradients were transformed and color-coded with three primary colors to compose a 3DAC image. Morphological changes of neuronal tracts were assessed. Fine anatomical structures of neuronal tracts were visible on 3DAC images, including pyramidal tract, medial leminscus, superior and middle cerebellar peduncles. Pathological findings of these tracts were categorized as compression or displacement, alteration of fiber directionality, involvement in tumor invasion or perifocal edema, and loss of anisotropy characterized by fading of their own color. Among these, only the loss of anisotropy was correlated with presenting tract-related deficits. The 3DAC imaging is useful to evaluate infratentorial neuronal tracts and to provide useful information to determine surgical strategy in patients with infratentorial brain tumors.