Von PET und PET/CT zur PET/MRT: Ein technologisches Update

Zusammenfassung

Der vorliegende Beitrag beleuchtet die wichtigsten technologischen Neuerungen auf dem Gebiet der Positronen-Emissions-Tomografie (PET) der letzten Jahre. Sowohl auf Seiten der Hardware als auch im Bereich der eingesetzten Algorithmen sorgt der Fortschritt dafür, dass die PET-Bildgebung einer der grundlegenden Pfeiler der nuklearmedizinischen Diagnostik bleiben wird. Insbesondere neue Detektoren (Szintillatormaterialien, Lichtdetektoren, Elektronik) – nicht nur für die neue PET/MRT-Bildgebung, sondern auch für die konventionelle PET/CT-Bildgebung – als auch neue Rekonstruktions- und Korrekturmethoden (iterative sowie Flugzeit- und Punktspreizantwort-basierte Rekonstruktionen, Schwächungs- und Bewegungskorrektur) sind für diese Entwicklung verantwortlich. Besonders im Hinblick auf gesteigerte Sensitivitäten und räumliche Auflösung ergeben sich hiermit interessante Perspektiven sowohl für die Grundlagenforschung als auch für klinische Anwendungen.

Abstract

This contribution presents the most important technological improvements in the field of positron emission tomography (PET) during the last few years. Progress on both hardware as well as the applied algorithms lead to the fact that PET will remain one of the basic buttresses of diagnostic imaging in nuclear medicine. In particular, new detectors (scintillator materials, light detectors, electronics) – not just for the recently introduced PET/MR imaging but also for conventional PET/CT imaging – as well as novel reconstruction and correction methods (iterative, time-of-flight- and point-spread-function-based reconstructions, attenuation and motion correction) are responsible for this advancement. This leads to exciting perpectives specifically in terms of increased sensitivities and spatial resolution both for basic research tasks and clinical applications.

Schlüsselwörter

PET - PET/CT - PET/MRT - Detektoren - Korrekturen - Artefakte

Key words

PET - PET/CT - PET/MRT - detectors - corrections - artifacts

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