Protokoll- und Dosisoptimierung der CT in der Hybridbildgebung für Schwächungskorrektur und strukturelle Korrelation

Zusammenfassung

Im Rahmen der Hybridbildgebung mit SPECT/CT und PET/CT wird die CT in der Regel als eine nicht diagnostische low-dose-Untersuchung (sog. auxiliäre CT) durchgeführt. Die CT-Daten dienen dabei der Schwächungskorrektur und bieten die Möglichkeit einer morphologischen Korrelation nuklearmedizinischer Befunde. Als Strahlungsanwendung unterliegt auch diese Form der CT dem allgemeinen Optimierungsgebot. Abhängig vom Anwendungsszenario sind dabei verschiedene Schwerpunkte zu berücksichtigen. Beispielhaft sind der potenzielle Einfluss der CT-Rekonstruktion auf die Schwächungskorrektur der Emissionsdaten, die Erkennbarkeit von anatomischen Strukturen oder auch die strahlenbiologische Optimierung für spezielle Patientengruppen (z. B. Kinder) zu nennen. Zu beachten ist, dass parallel zu den Optimierungsbestrebungen auch eine zunehmende Regulierung der auxiliären CT-Anwendungen stattfindet.

Abstract

In the context of hybrid imaging using SPECT/CT and PET/CT, CT is usually performed as a non-diagnostic low-dose examination (so-called auxiliary CT). In this case, the CT data are used for attenuation correction and offer the possibility of an anatomical correlation of nuclear medicine findings. As a radiation application, this form of CT is also subject to the general optimization rule. Depending on the application scenario, various key aspects must be taken into account. Examples include the potential influence of CT reconstruction on the attenuation correction of emission data, the detectability of anatomical structures, or radiobiological optimization for special patient groups (e. g. children). It should be noted that, in parallel to the optimization activities, there is also an increasing regulation of auxiliary CT applications.

Schlüsselwörter

Hybridbildgebung - auxiliäre CT - Schwächungskorrektur - iterative Rekonstruktion - CT-Rekonstruktion - Dosisreduktion

Key words

hybrid imaging - auxiliary CT - attenuation correction - iterative reconstruction - CT reconstruction - dose reduction

Publication History

Article published online:
16 August 2022

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