CT Brain with or without Contrast

Computed tomography (also CAT or CT scan) of the brain (cerebral hemispheres, cerebellum and brain stem.)


A CT brain is ordered to look at the structures of the brain and evaluate for the presence of pathology, such as mass/tumor, fluid collection (such as an abcess), ischemic processes (such as a stroke). It is particularly good for hemorrhage, trauma or fracture to the skull and for hydrocephalus.

  • Bone abnormalities
  • Brain mass/tumor
  • Fluid collection, such as an abcess
  • Hemorrhage
  • Hydrocephalus
  • Ischemic process, such as a stroke
  • Trauma or fracture of the skull


CT of the brain can be done with or without contrast, but it is often not needed.

In general, it is preferred that the choice of contrast or no contrast be left up to the discretion of the imaging physician.


Without Contrast:

No preparation is required.

With Contrast:
  • Only one CT contrast study should be scheduled within a 48 hour period.
  • BUN & Creatinine must be done within 72 hours of the scan.
  • Nothing but clear liquid after midnight before the scan.
  • NPO 4 hours prior to exam (no food or drink).