Absolute quantification of perfusion using dynamic susceptibility contrast MRI: pitfalls and possibilities

Abstract

Absolute quantification of cerebral blood flow, cerebral blood volume and mean transit time is desirable in the determination of tissue viability thresholds and tissue at risk in acute ischaemic stroke, as well as in cases where a global reduction in cerebral blood flow is expected, for example, in patients with dementia or depressive disorders. Absolute values are also useful when comparing sequential examinations of tissue perfusion parameters, for example, in the monitoring and follow-up of various kinds of therapy. Regardless of the method employed, a number of assumptions and approximations must be made to obtain absolute measures of perfusion. Furthermore, the different stages of data acquisition and processing are associated with various degrees of uncertainty. In this review, the problems of particular relevance to absolute quantification of cerebral perfusion parameters using dynamic susceptibility contrast magnetic resonance imaging are discussed, and possible solutions are outlined.

Perfusion Measurement in Brain Gliomas with Intravoxel Incoherent Motion MRI

“…It is intrinsically quantitative, and, because of the intravoxel excitation and readout, it does not require a precise knowledge of the arterial input function, which is challenging to measure. [32][33][34] It does not require contrast media and enables the acquisition of perfusion and diffusion information in a single sequence.…”

Increased brain perfusion contrast with T2‐prepared intravoxel incoherent motion (T2prep IVIM) MRI

“…A reproducible increase in subjective lesion detection and diagnostic confidence was observed, in comparison with IVIM, and importantly also in comparison with currently used DSC, and might therefore be of interest in daily clinical tumor assessment. These results add to the already demonstrated advantages of this technique, including direct intratumoral perfusion assessment (5), without DSC's requirement for contralateral normalization measurement (which can be difficult because of anatomical distortion), lack of dependence on the arterial input function, which is known to be difficult to measure (32)(33)(34), and no need for intravenous contrast injection.…”

Assessment of Cortical Hemodynamics by Multichannel Near-Infrared Spectroscopy in Steno-Occlusive Disease of the Middle Cerebral Artery

“…More prevalent techniques based on bolus application of an intravascular contrast medium, however, are prone to inaccuracies in the determination of cerebral blood flow. [17][18][19] As a consequence, perfusion-related parameters like TTP, which can be determined from bolus dynamics in a numerically robust way, are increasingly used to characterize cerebral hemodynamics, an approach that was adopted here for analysis of multichannel NIRS.…”