Brain tumor CT

Overview
Imaging plays a central role in the diagnosis of brain tumors. Early imaging methods&mdash;invasive and sometimes dangerous&mdash;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).

CT Scan
Benign brain tumors often show up as hypodense (darker than brain tissue) mass lesions on cranial CT-scans. 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.

Computed tomography (CT) and magnetic resonance imaging (MRI) have complementary roles in the diagnosis of CNS neoplasms. The speed of CT is desirable for evaluating clinically unstable patients. CT is superior for detecting calcification, skull lesions, and hyperacute hemorrhage (bleeding less than 24-hours old) and helps direct differential diagnosis as well as immediate management.