Multimodal MR imaging: Functional, diffusion tensor, and chemical shift imaging in a patient with localization-related epilepsy

Purpose: To demonstrate the integration of complementary functional and str uctural data acquired with magnetic resonance imaging (MRI) in a patient wi th localization-related epilepsy. Methods: We studied a patient with partial and secondarily generalized seiz ures and a hemiparesis due to a malformation of cortical development (MCD) in the right hemisphere by using EEG-triggered functional MRI (fMRI), diffu sion tensor imaging (DTI), and chemical shift imaging (CSI). Results: fMRI revealed significant changes in regional blood oxygenation as sociated with interictal epileptiform discharges within the MCD. DTI showed a heterogeneous microstructure of the MCD with reduced fractional anisotro py, a high mean diffusivity, and displacement of myelinated tracts. CSI dem onstrated low N-acetyl aspartate (NAA) concentrations in parts of the MCD. Conclusions: The applied MR methods described functional, microstructural, and biochemical characteristics of the epileptogenic tissue that cannot be obtained with other noninvasive means and thus improve the understanding of the pathophysiology of epilepsy.