Brain tumor MRI

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Brain tumor Microchapters
Patient Information
Overview
Classification Adult brain tumors Glioblastoma multiforme Oligodendroglioma Meningioma Hemangioblastoma Pituitary adenoma Schwannoma Primary CNS lymphoma Childhood brain tumors Pilocytic astrocytoma Medulloblastoma Ependymoma Craniopharyngioma Pinealoma Metastasis Lung cancer Breast cancer Melanoma Gastrointestinal tract cancer Renal cell carcinoma Osteoblastoma Head and neck cancer Neuroblastoma Lymphoma Prostate cancer
Causes
Differentiating Brain Tumor from other Diseases

Overview

Imaging plays a central role in the diagnosis of brain tumors. Early imaging methods—invasive and sometimes dangerous—such as pneumoencephalography and cerebral angiography, have been abandoned in recent times in favor of non-invasive, high-resolution modalities, such as computed tomography (CT) and especially magnetic resonance imaging (MRI).

MRI

On MRI, they appear either hypo- (darker than brain tissue) or isointense (same intensity as brain tissue) on T1-weighted scans, or hyperintense (brighter than brain tissue) on T2-weighted MRI. Perifocal edema also appears hyperintense on T2-weighted MRI. Contrast agent uptake, sometimes in characteristic patterns, can be demonstrated on either CT or MRI-scans in most malignant primary and metastatic brain tumors. This is due to the fact that these tumors disrupt the normal functioning of the blood-brain barrier and lead to an increase in its permeability.

MRI has superior soft-tissue resolution. MRI can better detect isodense lesions, tumor enhancement, and associated findings such as edema, all phases of hemorrhagic states (except hyperacute), and infarction. High-quality MRI is the diagnostic study of choice in the evaluation of intramedullary and extramedullary spinal cord lesions.