Perfusion MRI

Perfusion MRI is a neuroimaging technique which can measure the local perfusion of brain tissues.

Technique

A bolus of contrast agent is injected in a peripheral vein while the patient's brain is being repeatedly scanned. The passage of the contrast agent induces and hyper- or hypo-intensity. On t2*-weighted EPI images, susceptibility of the contrast agent is the main source of (negative) contrast.

Contrast agent

The most common contrast agents in MRI are gadolinium chelates, for example Gd-DTPA. For perfusion imaging, they are injected as a bolus (for example 6 ml/s), i.e. in one relatively quick step.