Journal of Isfahan Medical School

Journal of Isfahan Medical School

The Effect of fixation equipment used in radiotherapy on the quality of magnetic resonance images of the brain region

Document Type : Original Article(s)

Authors
Ebrahim Borghabani 1
Mahdi Momennezhad 2
Shahrokh Naseri 2
Seiedeh Fatemeh Ayati fard 3
Atefe Rostami 4
1 Department of Radiology, Shahid Beheshti Emdam Hospital, Sabzevar University of Medical Sciences, Sabzevar, Iran
2 Department of Medical Physics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
3 Department of Medical Physics and Radiation Sciences, Faculty of Paramedical Sciences, Sabzevar University of Medical Sciences, Sabzevar, Iran
4 Associate Professor, Department of Medical Physics and Radiation Sciences, Faculty of Paramedical Sciences, Sabzevar University of Medical Sciences, Sabzevar, Iran
10.48305/jims.v44.i854.0314
Abstract
Background: The high contrast inherent in soft tissue, coupled with the capacity to implement a variety of imaging protocols and acquire functional data through magnetic resonance imaging (MRI), significantly enhances the precision of treatment planning of radiotherapy. In this study, the effect of radiotherapy positioning equipment on MR image quality of brain region was evaluated.
Methods: MRI images of homogenous phantom and 10 patients in T1 and T2 protocols with brain coil in the diagnostic MR position and using thermoplastic mask in the treatment position of radiotherapy were taken. MRI images using Medical image analysis and processing software (3D Slicer) were compared in terms of image quality with the signal-to-noise ratio (SNR) parameter.
Findings: The average percentage of SNR reduction was measured more in the T1 protocol in both phantom and patient images. The highest percentage of SNR reduction for the phantom in the posterior part was obtained for the T1 and T2 protocols, 13.23 and 11.21 percent, respectively. The lowest percentage of SNR reduction for the phantom in the anterior part was obtained for the T1 and T2 protocols, 6.81 and 4.46 percent, respectively.
Conclusion: Correcting the patient's body position using flat overlay table and thermoplastic fixation base during MRI imaging, similar to radiotherapy sessions, can increase the accuracy of CT and MRI images registration with a slight decrease in image quality and can be used in treatment planning using MRI images.

Highlights

Atefe Rostami: Google Scholar, PubMed

Keywords
Fixation devices
thermoplastic polyester mask
image enhancement
magnetic resonance imaging
Radiotherapy
Subjects
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Journal of Isfahan Medical School
Volume 44, Issue 854
2nd Week, May
May and June 2026
Pages 314-322

  • Receive Date 12 January 2025
  • Accept Date 17 May 2026