How much CT do we need for PET/CT?

Summary:

In clinical practice different CT imaging protocols are implemented within combined PET/CT acquisition protocols. From a radiologist´s perspective the full potential of PET/ CT for oncology imaging can be used only by exploring the full capacity of the CT. This mandates the use of oral and intravenous contrast material as well as a CT image quality which proves diagnostically sufficient by radiology standards. The integration of a fully-diagnostic CT exam portion into combined PET/CT is demanding and requires adjustments of CT acquisition protocols. Given the use of the CT for CT-based attenuation correction potential PET/CT image artefacts have to be considered as well. In this paper we review radiological perspectives on PET/CT imaging.

Zusammenfassung:

Im klinischen Alltag werden sehr unterschiedliche CT-Protokolle in der kombinierten PET/CT-Bildgebung verwendet. Sie reflektieren die verschiedenen Herangehensweisen der Nuklearmedizin bzw. Radiologie an die bimodale Schnittbilddiagnostik. Aus Sicht des Radiologen erschließt nur die möglichst vollständige Ausnutzung der CT-eigenen Möglichkeiten das volle Potenzial des PET/CT in der onkologischen Bildgebung. Das beinhaltet die Verwendung von oralen und intravenösen Kontrastmittelapplikationen sowie eine für die Diagnostik ausreichende Bildqualität. Die Integration eines voll diagnostischen CT in die kombinierte Modalität PET/CT ist technisch und organisatorisch anspruchsvoll und erfordert umfangreiche Anpassungen der CT-Untersuchungstechnik und -protokolle. Die durch die CT-basierte Schwächungskorrektur bedingten Artefaktmöglichkeiten der fusionierten Bildgebung müssen dabei berücksichtigt werden. Im Folgenden werden radiologische Gesichtspunkte der PET/CT-Bildgebung dargestellt.

Key words:

CT - PET/CT

Schlüsselwörter:

CT - PET/CT

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