Visualization of Ischaemic Penumbra Using a Computed Tomography Perfusion Method

Abstract

A computed tomography (CT) perfusion imaging and a diffusion/perfusion magnetic resonance imaging (MRI) were performed in a 51-year-old man at 15 and 15.5 h of onset of left middle cerebral artery infarction, respectively. The established infarct, as revealed by the diffusion-weighted MRI, had low values of cerebral blood flow (CBF) and cerebral blood volume (CBV) on the CT perfusion study. The ischaemic penumbra, as reflected by the perfusion-diffusion mismatch on MRI, had reduced CBF, prolonged mean transit time (MTT) and compensated CBV. Spontaneous bleeding occurred in the medial part of the left lentiform nucleus, immediately following decompressive craniectomy. CT measurements of CBF, CBV and MTT may visualize the ischaemic penumbra and explain the site of bleeding after surgical decompression.