Time‐resolved magnetic resonance angiography

Abstract

A time-resolved phase contrast magnetic resonance angiography technique is described. This technique provides a series of angiograms obtained at different phases of the cardiac cycle. Such a series of angiograms can be used to evaluate blood flow dynamics. For example, turbulent flow in the regions of vessel bifurcations is easily demonstrated and followed during systole and diastole. Retrograde flow can also be observed. Dynamic angiography can be particularly useful in distinguishing transient image features, such as signal voids due to turbulent flow, from static features arising from vessel morphology.

Magnetization transfer time‐of‐flight magnetic resonance angiography

“…For example, projection angiography techniques based on phase-contrast (20) or TOF (21,22) acquisitions often use a projection dephaser gradient to reduce the stationary tissue signal. These gradients can result in signal loss in regions of vessel overlap (23) and might therefore be replaced with an 'H, saturation scheme.…”

MR-Angiographie: Technische Grundlagen und Anwendungen in der Diagnostik neurologischer Erkrankungen

“…Hier empfiehlt sich eine EKG-Triggerung, die zudem den Vorteil hat, dass Messungen zu mehreren definierten Zeitpunkten durchgeführt und dann dynamisch im Cine-Modus dargestellt werden können [16].…”

Functional Magnetic Resonance Imaging in Medicine and Physiology

“…Since blood flow in the human body is mostly pulsatile, MR angiographic methods have recently been designed to measure the time dependence of flow velocity (15). Another approach is to measure the acceleration of flow using specially designed gradient pulses (16).…”