Data from: Automated CT perfusion imaging for acute ischemic stroke: pearls and pitfalls for real world use

Recent positive trials have thrust acute cerebral perfusion imaging into
the routine evaluation of acute ischemic stroke. Updated guidelines state
that in patients with anterior circulation large vessel occlusions
presenting beyond 6 hours from time last known well, advanced imaging
selection including perfusion based selection is necessary. Centers that
receive acute stroke patients must now have the capability to perform and
interpret CT or MR perfusion imaging, or provide rapid transfer to centers
with the capability of selecting patients for a highly impactful
endovascular therapy, particularly in delayed time windows. Many stroke
centers are quickly incorporating the use of automated perfusion
processing software to interpret perfusion raw data. As CT perfusion is
being assimilated in real world clinical practice, it is essential to
understand the basics of perfusion acquisition, quantification and
interpretation. It is equally important to recognize the common technical
and clinical diagnostic challenges of automated CTP including ischemic
core and penumbral misclassifications that could result in underestimation
or overestimation of the core and penumbra volumes. This review highlights
the pitfalls of automated CT perfusion along with practical pearls to
address the common challenges. This is particularly tailored to aid the
acute stroke clinician who must interpret automated perfusion studies, in
an emergency setting to make time-dependent treatment decisions for acute
ischemic stroke patients.