Fundamental Radiological Findings: Increased Signal Attenuation In The Brain (Non-Contrast Head CT Scan)

OVERVIEW

This page is dedicated to covering the important radiological finding of increased signal attenuation in the brain (0n a non-contrast head CT-scan). 

WHAT IS IT?

Increased signal attenuation refers to a finding on CT studies where a tissue/structure appears to “more white” for a certain reason. In the case of a non-contrast CT-scan this reason will be due to an increased density of the structure in question.

The above example shows axial, coronal, and sagittal views of an area of increased signal attenuation on this non-contrast head CT scan.
DIFFERENTIAL DIAGNOSIS FOR THIS FINDING

When seeing a increased signal attenuation in the brain (0n a non-contrast head CT-scan), it is important to keep in mind the following possible causes of this finding:

  • Bleeding
  • Neoplasm
  • Vascular malformations 
KEY FEATURES TO LOOK FOR WHEN CHARACTERIZING THE FINDING

When seeing a increased signal attenuation in the brain (0n a non-contrast head CT-scan), there are a few important radiological features one should look at to try and characterize the finding. These features can help navigate the differential diagnosis above.

  • Location: is the mass inside or outside the brain parenchyma (intraaxial vs. extraxial?)

 

Page Updated: 08.23.2017