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Assessment of image quality of a radiotherapy-specific hardware solution for PET/MRI in head and neck cancer patients.

ABSTRACT: BACKGROUND AND PURPOSE:Functional PET/MRI has great potential to improve radiotherapy planning (RTP). However, data integration requires imaging with radiotherapy-specific patient positioning. Here, we investigated the feasibility and image quality of radiotherapy-customized PET/MRI in head-and-neck cancer (HNC) patients using a dedicated hardware setup. MATERIAL AND METHODS:Ten HNC patients were examined with simultaneous PET/MRI before treatment, with radiotherapy and diagnostic scan setup, respectively. We tested feasibility of radiotherapy-specific patient positioning and compared the image quality between both setups by pairwise image analysis of 18F-FDG-PET, T1/T2-weighted and diffusion-weighted MRI. For image quality assessment, similarity measures including average symmetric surface distance (ASSD) of PET and MR-based tumor contours, MR signal-to-noise ratio (SNR) and mean apparent diffusion coefficient (ADC) value were used. RESULTS:PET/MRI in radiotherapy position was feasible - all patients were successfully examined. ASSD (median/range) of PET and MR contours was 0.6 (0.4-1.2) and 0.9 (0.5-1.3) mm, respectively. For T2-weighted MRI, a reduced SNR of -26.2% (-39.0--11.7) was observed with radiotherapy setup. No significant difference in mean ADC was found. CONCLUSIONS:Simultaneous PET/MRI in HNC patients using radiotherapy positioning aids is clinically feasible. Though SNR was reduced, the image quality obtained with a radiotherapy setup meets RTP requirements and the data can thus be used for personalized RTP.

SUBMITTER: Winter RM

PROVIDER: S-EPMC6141811 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Assessment of image quality of a radiotherapy-specific hardware solution for PET/MRI in head and neck cancer patients.

Winter René M RM Leibfarth Sara S Schmidt Holger H Zwirner Kerstin K Mönnich David D Welz Stefan S Schwenzer Nina F NF la Fougère Christian C Nikolaou Konstantin K Gatidis Sergios S Zips Daniel D Thorwarth Daniela D

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology 20180507 3

<h4>Background and purpose</h4>Functional PET/MRI has great potential to improve radiotherapy planning (RTP). However, data integration requires imaging with radiotherapy-specific patient positioning. Here, we investigated the feasibility and image quality of radiotherapy-customized PET/MRI in head-and-neck cancer (HNC) patients using a dedicated hardware setup.<h4>Material and methods</h4>Ten HNC patients were examined with simultaneous PET/MRI before treatment, with radiotherapy and diagnostic ...[more]

PMID: 29747873

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Dataset Information

Assessment of image quality of a radiotherapy-specific hardware solution for PET/MRI in head and neck cancer patients.

Publications

Assessment of image quality of a radiotherapy-specific hardware solution for PET/MRI in head and neck cancer patients.

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