Article

Evaluation of cerebral perfusion parameters measured by perfusion CT in chronic cerebral ischemia: comparison with xenon CT.

Department of Radiology, Yamaguchi University School of Medicine, Yamaguchi, Japan.
Journal of Computer Assisted Tomography (impact factor: 1.22). 26(2):272-8. pp.272-8
Source: PubMed

ABSTRACT The purpose of this work was to evaluate the usefulness of perfusion CT in the evaluation of patients with chronic cerebral ischemia by comparing it with xenon CT (Xe-CT).
Cerebral blood flow (CBF) of perfusion CT (CBFper) and time to peak (TTP) were compared with the CBF of Xe-CT (CBFxe) in 18 patients. Cerebral blood volume (CBV) was compared with cerebral vascular reserve (CVR) in 10 of 18 patients who underwent pre- and postacetazolamide Xe-CT.
CBFper and TTP demonstrated a high correlation with CBFxe in relative values by side-to-side comparisons (r = 0.743, p < 0.0001 and r = -0.760, p < 0.0001, respectively). There was a negative correlation between relative CBV and relative CVR (r = -0.637, p = 0.0025). Visually, territories with delayed TTP corresponded well to those of decreased CBFxe, but these territories tended to be larger in TTP maps.
Perfusion CT is a useful tool to evaluate chronic hemodynamic disturbance and can be an alternative method for those using acetazolamide challenge.

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Matakazu Furukawa