Emergency Radiology

, Volume 21, Issue 1, pp 49–65 | Cite as

CT perfusion in acute stroke: Know the mimics, potential pitfalls, artifacts, and technical errors

  • Rajiv Mangla
  • Sven Ekhom
  • Babak S. Jahromi
  • Jeevak Almast
  • Manisha Mangla
  • Per-Lennart Westesson
Pictorial Essay


The CT perfusion (CTP) imaging of brain has been established as a clinically useful tool in multimodality imaging of acute stroke. All abnormalities seen on perfusion CT are not specifically related to acute infarct. There are many neurologic diseases causing symptoms simulating cerebrovascular disease produce an alteration of brain perfusion and thus can result in perfusion CT abnormalities. There are many pitfalls and artifacts in acquiring the data, calculation of maps and choosing arterial input function. We analyze and classify all these aspects, to allow the technician and the radiologist to know exactly what to avoid and what to choose, and we indicate the way to improve the quality of examination. The knowledge of mimics and pitfalls in acute stroke imaging can be helpful in accurate interpretation of these examinations.


CT perfusion Acute stroke Technical pitfalls 



Computed tomography


CT perfusion


Cerebral blood volume


Mean transit time


Cerebral blood flow


Anterior cerebral artery


Middle cerebral artery


Diffusion-weighted imaging


Internal carotid artery


Noncontrast CT



The authors are grateful to Sarah Peangatelli, Radiology Graphics Imaging Specialist for providing assistant with images.

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Am Soc Emergency Radiol 2013

Authors and Affiliations

  • Rajiv Mangla
    • 1
  • Sven Ekhom
    • 1
  • Babak S. Jahromi
    • 1
    • 2
    • 3
  • Jeevak Almast
    • 1
  • Manisha Mangla
    • 1
  • Per-Lennart Westesson
    • 1
  1. 1.Department of Imaging SciencesUniversity of Rochester, School of Medicine and DentistryRochesterUSA
  2. 2.Department of NeurosurgeryUniversity of Rochester, School of Medicine and DentistryRochesterUSA
  3. 3.Department of NeurologyUniversity of Rochester, School of Medicine and DentistryRochesterUSA

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