CT and MRI of brain tumors

Imaging plays a crucial role in the management of patients with brain tumors. The technical improvement of computed tomography (CT) and magnetic resonance (MRI) with the development of, new imaging techniques strongly improved the detection and characterization of brain tumors. For the optimal therapeutic management of the oncologic patient not only the recognition of the lesion is needed, but also the exclusion of other diseases that can mimic brain tumors. The preoperative assessment of malignancy and of relationships of the tumor with surrounding eloquent structures are also necessary to allow the correct choice of therapy and to warn surgeons of possible risks of the surgical approach. This article is an overview of the current state of neuroimaging of the most frequent brain tumors including CT and MRI, perfusion weighted imaging (PWI), diffusion weighted imaging (DWI), diffusion tensor imaging (DTI), proton magnetic resonance spectroscopy (1H-MRS) and functional MRI based on blood oxygen level (fMRI BOLD). Indeed, in the last years, a transition took place from a purely anatomy-based radiology to one that incorporates functional, hemodynamic, metabolic, cellular, and cytoarchitectural alterations. Neuroimaging has evolved into a comprehensive diagnostic tool that allows the characterization of morphologic as well as biologic alterations to diagnose and grade brain tumors and to monitor and assess treatment response and patient prognosis.