Perfusion MR imaging: evolution from initial development to functional studies.

A critical indicator of tissue viability and function is blood delivery to the capillary bed (referred to as perfusion or tissue/capillary blood flow), so the measurement of this process has been pursued by many MR scientists. Perfusion MRI is currently an effective tool to non-invasively quantify cerebral blood flow (CBF) and to easily obtain its relative change due to neural activity or other stimulus. This article describes the author's experiences in perfusion MRI over the past quarter-century, including initial development of the field, development of a flow-sensitive alternating inversion recovery (FAIR) MRI technique, development of a functional oxygen consumption MRI measurement approach, validation of the FAIR technique, characterization of perfusion changes induced by neural activity, and determination of arterial blood volume.