Spatio-temporal bandwidth-based acquisition for dynamic contrast-enhanced magnetic resonance imaging.

Purpose: To develop a k-space formalism that provides a rationale for the design of variable-rate acquisition schemes for dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

Methods And Materials: The formalism, termed spatio-temporal bandwidth-based (STBB) analysis, is demonstrated using a priori modeling of object and enhancement characteristics typically observed in DCE-MRI of breast tumors. A temporally enhancing lesion is considered as a two-dimensional (2D) space-time object that possesses a corresponding spatio-temporal (k(y)-k(t)) energy spectrum.

Morphologic and functional magnetic resonance imaging of renal artery stenosis: a multireader tricenter study.

The effect of combined morphologic and functional magnetic resonance (MR) imaging on the interobserver and intermodality variability for the grading of renal artery stenosis is assessed. In a randomized, blinded tricenter analysis, seven readers evaluated 43 renal arteries on x-ray digital subtraction angiography (DSA), 3D-Gadolinium MR angiography (3D-Gd-MRA), cine phase-contrast flow measurement (PC-flow), and a combined analysis of the last two. Interobserver variability was assessed for the grading of renal artery stenosis as well as regional vessel visibility.