Dataset Information

Sensitivity analysis of different quality assurance methods for magnetic resonance imaging in radiotherapy.

ABSTRACT:

Background and purpose

There are currently no standard quality assurance (QA) methods for magnetic resonance imaging (MRI) in radiotherapy (RT). This work was aimed at evaluating the ability of two QA protocols to detect common events that affect quality of MR images under RT settings.

Materials and methods

The American College of Radiology (ACR) MRI QA phantom was repeatedly scanned using a flexible coil and action limits for key image quality parameters were derived. Using an exploratory survey, issues that reduce MR image quality were identified. The most commonly occurring events were introduced as provocations to produce MR images with degraded quality. From these images, detection sensitivities of the ACR MRI QA protocol and a commercial geometric accuracy phantom were determined.

Results

Machine-specific action limits for key image quality parameters set at mean±3? were comparable with the ACR acceptable values. For the geometric accuracy phantom, provocations from uncorrected gradient nonlinearity effects and a piece of metal in the bore of the scanner resulted in worst distortions of 22.2 mm and 3.4 mm, respectively. The ACR phantom was sensitive to uncorrected signal variations, electric interference and a piece of metal in the bore of the scanner but could not adequately detect individual coil element failures.

Conclusions

The ACR MRI QA phantom combined with the large field-of-view commercial geometric accuracy phantom were generally sensitive in identifying some common MR image quality issues. The two protocols when combined may provide a tool to monitor the performance of MRI systems in the radiotherapy environment.

SUBMITTER: Adjeiwaah M

PROVIDER: S-EPMC7807625 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Publications

Sensitivity analysis of different quality assurance methods for magnetic resonance imaging in radiotherapy.

Adjeiwaah Mary M Garpebring Anders A Nyholm Tufve T

Physics and imaging in radiation oncology 20200101

<h4>Background and purpose</h4>There are currently no standard quality assurance (QA) methods for magnetic resonance imaging (MRI) in radiotherapy (RT). This work was aimed at evaluating the ability of two QA protocols to detect common events that affect quality of MR images under RT settings.<h4>Materials and methods</h4>The American College of Radiology (ACR) MRI QA phantom was repeatedly scanned using a flexible coil and action limits for key image quality parameters were derived. Using an ex ...[more]

PMID: 33458303

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Dataset Information

Sensitivity analysis of different quality assurance methods for magnetic resonance imaging in radiotherapy.

Background and purpose

Materials and methods

Results

Conclusions

Publications

Sensitivity analysis of different quality assurance methods for magnetic resonance imaging in radiotherapy.

Similar Datasets

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