Neue Entwicklungen in der MSCT

Zusammenfassung

Im Fokus der Weiterentwicklung in der MSCT stehen aktuell neue Anwendungen und die Softwareentwicklung. Ein wichtiges Thema ist dabei die Multispektrenbildgebung, die unter Verwendung von mindestens 2 verschiedenen Energiestufen eine Gewebedifferenzierung erlaubt. Neben der Differenzierung von Kalk und Jod für die CT-Angiografie und für onkologische Fragestellungen findet sie zunehmendes Interesse auch in anderen Anwendungsfeldern. Durch die ultraschnelle Bildgebung werden Atem- und Pulsationsartefakte weitgehend eliminiert, sodass eine Untersuchung auch bei mangelnder Compliance des Patienten meist ohne Sedierung oder Narkose möglich wird. Perfusionsuntersuchungen können durch große Detektorbreiten oder durch die sog. Shuffle-Technik auf ganze Körperregionen ausgedehnt werden. Neue Softwareentwicklungen umfassen iterative Rekonstruktionsalgorithmen und die organspezifische Dosismodulation für die Dosisreduktion.

Abstract

Progress in MSCT is focused on new applications and software development. A hot topic is multispectral imaging which allows for tissue differentiation using at least two energy-levels. Besides differentiation of calcification and jodine in CT-angiography and oncologic imaging, there is also increasing interest in other application fields. Ultrafast imaging nearly eliminates breathing and pulsation artifacts allowing examination of non-compliant patients without sedation or anesthesia. Perfusion can now be extended to large body regions using large detectors or applying shuffle-techniques. New software developments include iterative reconstruction and organ specific dose modulation allowing for dose reduction and for protection of radiosensitive organs.

Keywords

MSCT - multi detector row CT - new developments

Kernaussagen

• In der MSCT liegt der Fokus der Weiterentwicklungen auf neuen Anwendungen und der Softwareentwickung – weniger auf der weiteren Zunahme der Zeilenzahl.

• Die Multispektrenbildgebung (Dual Energy) erlaubt die Analyse von Gewebezusammensetzungen.

• Durch die ultraschnelle Bildgebung werden auch bei mangelnder Compliance des Patienten Untersuchungen ohne Sedierung oder Intubation möglich.

• Die iterativen Rekonstruktionsalgorithmen und die organspezifische Dosismodulation haben das Potenzial, die Dosis zu reduzieren bzw. strahlensensible Organe zu schonen.

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