Anwendung von Grundprinzipien der Physik bei der Magnetresonanzangiografie von Kopf und Hals: Erkennung von Artefakten^[1]

Zusammenfassung

Bildgebende Untersuchungen von Nerven und Gefäßen zur Abklärung von Kopfschmerzen und psychischen Veränderungen, zum Workup nach einem Schlaganfall und zur Beurteilung der arteriovenösen Strukturen von Kopf und Hals gehören zur klinischen Routine. Derartige Untersuchungen werden immer häufiger durchgeführt, da der Anteil älterer Menschen an der Gesamtbevölkerung ständig wächst. Verschiedene Verfahren der Magnetresonanzangiografie sind in dieser Situation hilfreich. Jedoch erfordert die Beherrschung dieser Techniken ein tiefgehendes Verständnis der physikalischen Grundprinzipien, der komplexen Fließmuster und der Korrelation zwischen magnetresonanzangiografischen und konventionellen magnetresonanztomografischen Befunden. Zur Klärung schwieriger Fälle können mehrere Bildgebungsverfahren kombiniert werden, wobei jedes von ihnen spezifische Informationen liefert. Leider stellt die Integration der mit den verschiedenen Bildgebungsmodalitäten gewonnenen Befunde eine zusätzliche diagnostische Herausforderung dar. Um die Richtigkeit der Diagnosen zu gewährleisten, muss der Radiologe die Details all dieser Befunde sorgfältig im Lichte der physikalischen Grundprinzipien, der Grundlagen der verschiedenen Bildgebungstechniken und der Kenntnis häufiger Fehlerquellen bei der bildgebenden Untersuchung neurovaskulärer Strukturen würdigen.

Abstract

Neurovascular imaging studies are routinely used for the assessment of headaches and changes in mental status, stroke workup, and evaluation of the arteriovenous structures of the head and neck. These imaging studies are being performed with greater frequency as the aging population continues to increase. Magnetic resonance (MR) angiographic imaging techniques are helpful in this setting. However, mastering these techniques requires an in-depth understanding of the basic principles of physics, complex flow patterns, and the correlation of MR angiographic findings with conventional MR imaging findings. More than one imaging technique may be used to solve difficult cases, with each technique contributing unique information. Unfortunately, incorporating findings obtained with multiple imaging modalities may add to the diagnostic challenge. To ensure diagnostic accuracy, it is essential that the radiologist carefully evaluates the details provided by these modalities in light of basic physics principles, the fundamentals of various imaging techniques, and common neurovascular imaging pitfalls.

¹ © 2013 The Radiological Society of North America. All rights reserved. Originally puplished in English in RadioGraphics 2013; 33: E113 – E123. Online published in 10.1148 /rg.333125148. Translated and reprinted with permission of RSNA. RSNA is not responsible for any inaccuracy or error arising from the translation from English to German.

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