Imaging of Stroke: Part 1, Perfusion CT???Overview of Imaging Technique, Interpretation Pearls, and Common Pitfalls

Abstract

Perfusion CT has proven to be a valuable tool in the diagnosis of acute ischemic stroke. The knowledge provided by these cases will allow the reader not only to confidently identify the presence of acute ischemic stroke, but also to recognize the common pitfalls and limitations of perfusion CT in this setting.

The Use of Thermographic Camera in Stroke Diagnostics - Introductory Report

“…25% of patients with TIA have a stroke or other vascular incidents within the next three months. Allmendinger et al [18] describe in their work the benefits of perfusion CT as the most frequently used diagnostic tool in acute ischemic stroke evaluation. It can be performed quickly and is generally accessible.…”

Imaging Patterns and Management Algorithms in Acute Stroke

“…Various parameters are calculated: (1) cerebral blood volume (CBV) is a measure of the total volume of blood within an imaging voxel including blood in the tissues and blood vessels; (2) cerebral blood flow (CBF) is a measure of the total volume of blood moving through a voxel in a given unit of time; (3) MTT is the time difference between the arterial inflow and venous outflow; (4) time to peak enhancement is the time from the beginning of contrast material injection to the maximum concentration of contrast material within a region of interest, and (5) T max is the time at which the convolved residue function reaches its maximum. [98][99][100][101] The evaluation of brain perfusion is based on the central volume principle, according to which, MTT 5 CBV/CBF. These parameters are derived from perfusion source data using deconvolution analyses and color-coded perfusion maps can be generated automatically at the scanner.…”

Cerebral Blood Flow Assessment by Digital Subtraction Angiography

“…Some procedures are further limited by acceptable radiation dosage and unavailability of these techniques in smaller hospitals. Some studies [13][14][15] have also cast doubt on perfusion methods for identifying infarct regions, because they involve image interpretation with respect to arbitrary mismatch thresholds.…”