Parallele Bildgebung in der Magnetresonanztomographie

Zusammenfassung

Die parallele Bildgebung ist ein neues innovatives Verfahren, um die MRT zu beschleunigen, ohne den Bildkontrast zu verändern. Anders als die traditionellen Methoden wird diese Beschleunigung ohne den Einsatz schnellerer Gradientensysteme erreicht - vielmehr nutzt die parallele Bildgebung die räumlichen Informationen von verschiedenen Empfangsspulen. Aus einem MR-Echo werden mehrere Phasenkodierinformationen gleichzeitig erzeugt, sodass man mit weniger Phasenkodierschritten auskommt und somit schneller die gleichen Bildinformationen erhält. Dieser Artikel zeigt die verschiedenen Rekonstruktionstechniken der parallelen Bildgebung und deren Einsatzgebiete sowie einen Ausblick in die nahe Zukunft dieser Technik.

Abstract

Parallel imaging is a new, innovative technique to accelerate magnetic resonance imaging without affecting the image contrast. Unlike traditional methods, this acceleration is not achieved by faster gradient hardware, rather parallel imaging uses the spatial information of multiple receiver coils. This allows for the acquisition of multiple phase encoding from a single signal echo, so that fewer phase encoding steps are needed for obtaining the same image information. This article gives an introduction to parallel imaging and its major applications, and provides an outlook into the future perspectives for these techniques.

Key words

Parallel imaging - Partial FoV - SMASH - SENSE - GRAPPA - Magnetic resonance imaging

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