Obtaining a non-contrast Head CT is one of the critical actions in evaluation of neurologic symptoms concerning for acute stroke. Evaluating the images involves scanning for the following features of ischemia of the brain parenchyma.

  1. Hypoattenuation involving one-third or more of the middle cerebral artery (MCA) territory.
  2. Obscuration of the lentiform nucleus.
  3. Cortical sulcal effacement.
  4. Focal parenchymal hypoattenuation.
  5. Loss of the insular ribbon or obscuration of the Sylvian fissure.
  6. Loss of gray-white matter differentiation in the bassal ganglia.