Experimentelle Kleintier-MRT: Klinische MRT-Systeme als Schnittstelle zur biomedizinischen Grundlagenforschung

Zusammenfassung

In den biomedizinischen Grundlagenfächern ist die Nachfrage nach hochaufgelöster Kleintier-MRT stetig steigend. Dedizierte Kleintiersysteme, die mit B 0-Feldern üblicherweise im Bereich von 4,7 T–7 T und oftmals auch darüber arbeiten, genügen selbst den höchsten Ansprüchen an die Bildqualität. Doch auch der Einsatz effizienter, hochauflösender RF-Spulen in der klinischen MRT bis zu 3.0 T ermöglicht detaillierte und kontrastreiche morphologische Darstellungen im Submillimeterbereich. So wird über die erfolgreiche Anwendung klinischer MRT-Geräte für Untersuchungen am Kleintier in der biomedizinischen Literatur vielfach berichtet. Am häufigsten sind Berichte über die Verwendung kleiner klinischer Spulen. Oftmals finden jedoch auch speziell entwickelte, volumenoptimierte RF-Spulen experimentelle Anwendung. Sehr anspruchsvolle Fragestellungen können mithilfe zusätzlicher Gradientenspulen in einem klinischen Scanner bearbeitet werden. Für die Reduktion von Bewegungsartefakten stehen spezielle kleintierangepasste EKG- und Atemsteuerungsgeräte zur Verfügung. Die Vorteile der klinischen MRT liegen in ihrer weiten Verbreitung, im geringeren finanziellen Aufwand bei guter Leistungsfähigkeit und auch in der translationalen Verwertbarkeit der Bildergebnisse.

Abstract

The demand for highly resolved small animal MRI for the purpose of biomedical research has increased constantly. Dedicated small animal MRI scanners working at ultra high field strengths from 4.7 to 7.0 T and even above are MRI at its best. However, using high resolution RF coils in clinical scanners up to 3.0 T, small animal MRI can achieve highly resolved images showing excellent tissue contrast. In fact, in abundant experimental studies, clinical MRI is used for small animal imaging. Mostly clinical RF coils in the single-loop design are applied. In addition, custom-built RF coils and even gradient inserts are used in a clinical scanner. For the reduction of moving artifacts, special MRI-compatible animal ECG und respiration devices are available. In conclusion, clinical devices offer broad availability, are less expense in combination with good imaging performance and provide a translational nature of imaging results.

Key words

MR imaging - equipment - molecular imaging - technical aspects

Literatur

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