Pseudo-continuous arterial spin labeling (pCASL) was developed for brain perfusion imaging without contrast agent. “This is very desirable in pediatric patients where the general trend is to limit the administration of contrast,” says Dr. Miller.
Dr. Miller uses pCASL for all patients who present with chronic and acute cerebrovascular abnormalities such as acute stroke, as well as patients who present with signs of acute inflammation in the brain, and occasionally in patients with tumors, to assess the perfusion status of their tumor.
“In combination with diffusion weighted imaging, it can help give a more extended assessment of the degree of perfusion abnormality in a patient who is suffering acute ischemia. We have a number of patients who have chronic arterial insufficiency due to prior arterial abnormalities or acquired arterial abnormalities such as sickle cell disease or neurofibromatosis. Sometimes the child’s first manifestation of disease progression is a reduction in brain perfusion before stroke symptoms manifest clinically or in diffusion weighted imaging. We use pCASL to help delineate the perfusion abnormality.”
Growing confidence in specific applications
“We built up confidence in pCASL by comparing it to contrast-based perfusion imaging. Once we had confidence that it was representing what the contrast perfusions were representing, we increased our diagnostic confidence by serial imaging in either the acute stage or the long term stages in a number of patients with arterial abnormalities.