Published in:
01-12-2014 | Oncology
Amplitude-based optimal respiratory gating in positron emission tomography in patients with primary lung cancer
Authors:
Willem Grootjans, Lioe-Fee de Geus-Oei, Antoi P. W. Meeuwis, Charlotte S. van der Vos, Martin Gotthardt, Wim J. G. Oyen, Eric P. Visser
Published in:
European Radiology
|
Issue 12/2014
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Abstract
Objectives
Respiratory motion during PET imaging introduces quantitative and diagnostic inaccuracies, which may result in non-optimal patient management. This study investigated the effects of respiratory gating on image quantification using an amplitude-based optimal respiratory gating (ORG) algorithm.
Methods
Whole body FDG-PET/CT was performed in 66 lung cancer patients. The respiratory signal was obtained using a pressure sensor integrated in an elastic belt placed around the patient’s thorax. ORG images were reconstructed with 50 %, 35 %, and 20 % of acquired PET data (duty cycle). Lesions were grouped into anatomical locations. Differences in lesion volume between ORG and non-gated images, and mean FDG-uptake (SUVmean) were calculated.
Results
Lesions in the middle and lower lobes demonstrated a significant SUVmean increase for all duty cycles and volume decrease for duty cycles of 35 % and 20 %. Significant increase in SUVmean and decrease in volume for lesions in the upper lobes were observed for a 20 % duty cycle. The SUVmean increase for central lesions was significant for all duty cycles, whereas a significant volume decrease was observed for a duty cycle of 20 %.
Conclusions
This study implies that ORG could influence clinical PET imaging with respect to response monitoring and radiotherapy planning.
Key Points
• Quantifying lesion volume and uptake in PET is important for patient management
• Respiratory motion artefacts introduce inaccuracies in quantification of PET images
• Amplitude-based optimal respiratory gating maintains image quality through selection of duty cycle
• The effect of respiratory gating on lesion quantification depends on anatomical location