Grundlagen, Umsetzung und klinische Anwendung der Dual-Energy-CT

Die neuesten Computertomografen messen die Schwächung hoch- und niederenergetischer Röntgenquanten separat und erlauben so neben der Berechnung konventioneller Bilder die Erstellung vieler weiterer Rekonstruktionen. Die so zur Verfügung stehenden virtuell monoenergetischen Bilder, Jodkarten, virtuell nativen Bilder u. v. a. erhalten zunehmend Einzug in sämtliche Domänen der CT-Diagnostik.

Kernaussagen

• In der Dual-Energy-CT (DECT) werden 2 verschiedene Energien eingesetzt. Damit können die untersuchten Objekte gezielter identifiziert und Gewebe besser charakterisiert werden.

• Bei den Konzepten zur DECT sind emissionsbasierte Ansätze (simultane Abtastung mit 2 verschiedenen Energien) von detektorbasierten Ansätzen (simultane Registrierung der Schwächung) zu unterscheiden.

• Die DECT ermöglicht nicht nur konventionelle CT-Bilder, sondern viele weitere Bildrekonstruktionen, z. B. virtuell monoenergetische Rekonstruktionen, virtuell native Bilder, Jodkarten, Karten der Elektronendichte oder der effektiven Ordnungszahl.

• Bei emissionsbasierten CTs im DECT-Modus ist entweder die Strahlenexposition (minimal) erhöht oder die Qualität konventioneller Bilder (minimal) reduziert.

Schlüsselwörter

Dual-Energy-CT - DECT - virtuell monoenergetische Bilder - Metallimplantate

Key words

dual-energy CT - DECT - virtual monoenergetic dual-energy CT - metallic implants

• Literatur

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