Integration of FDG- PET/CT into external beam radiation therapy planning

 

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Summary

This work addresses the clinical adoption of FDG-PET/CT for image-guided radiation therapy planning (RTP). As such, important technical and methodological aspects of PET/CTbased RTP are reviewed and practical recommendations are given for routine patient management and clinical studies. First, recent developments in PET/CT hardware that are relevant to RTP are reviewed in the context of quality control and system calibration procedures that are mandatory for a reproducible adoption of PET/CT in RTP. Second, recommendations are provided on image acquisition and reconstruction to support the standardization of imaging protocols. A major prerequisite for routine RTP is a complete and secure data transfer to the actual planning system. Third, state-of-the-art tools for image fusion and co-registration are discussed briefly in the context of PET/CT imaging preand post-RTP. This includes a brief review of state-of-the-art image contouring algorithms relevant to PET/CT-guided RTP. Finally, practical aspects of clinical workflow and patient management, such as patient setup and requirements for staff training are emphasized. PET/ CT-guided RTP mandates attention to logistical aspects, patient set-up and acquisition parameters as well as an in-depth appreciation of quality control and protocol standardization. Conclusion: Upon fulfilling the requirements to perform PET/CT for RTP, a new dimension of molecular imaging can be added to traditional morphological imaging. As a consequence, PET/CT imaging will support improved RTP and better patient care. This document serves as a guidance on practical and clinically validated instructions that are deemed useful to the staff involved in PET/CT-guided RTP.

Zusammenfassung

Diese Arbeit geht auf die klinische Verwendung von FDG-PET/CT in der bildgestützten Radiotherapieplanung (RTP) ein. Wichtige technische und methodische Aspekte der FDG-PET/CT-basierten RTP werden erläutert, und praktische Empfehlungen für das Management von Patienten in der klinischen Routine sowie in klinischen Studien gegeben. Zunächst werden neueste Hardware-Entwicklungen der PET/CT-Bildgebung beschrieben, die für die RTP relevant sind. Die Einführung entsprechender Qualitätskontrollen und Protokolle zur Kalibrierung bildgebender Systeme ist unerlässlich für eine reproduzierbare Einbeziehung der PET/CT in die RTP. Anschließend werden Empfehlungen hinsichtlich Datenakquisition und Rekonstruktionsparametern gegeben mit dem Ziel der Standardisierung der Bildgebungsprotokolle. Eine Haupt - anforderung der RTP in der klinischen Routine ist der zuverlässige Datentransfer an das Planungssystem. In einem weiteren Abschnitt dieser Arbeit werden aktuelle Methoden der Bildfusion und -registrierung diskutiert. Abschließend wird auf praktische Aspekte bezüglich klinischer Arbeitsabläufe und Patientenmanagement (z. B. Patientenlagerung und Anforderungen an die Personalschulung) eingegangen. Besonders wichtig für eine zuverlässige PET/CT-basierte RTP sind logistische Aspekte, aber auch eine reproduzierbare Lagerung der Patienten und standardisierte Akquisitionsprotokolle sowie spezielle Qualitätskontrollen. Schlussfolgerung: Durch Umsetzung der genannten Anforderungen der RTP an die PET/CT, kann die Integration molekularer Bilddaten zusätzlich zur morphologischen Bildgebung erreicht werden. Die PET/CT unterstützt eine präzisere RTP und ein verbessertes Patientenmanagement. Diese Arbeit kann als praktische Empfehlung zur klinischen Verwendung von PET/CT-Bilddaten in der RTP genutzt werden.

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