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Updated: Apr 28, 2026
06:08
Use of a Linear Accelerator for Conducting In Vitro Radiobiology Experiments
Published on: May 26, 2019
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The magnetic resonance imaging-linac system.
Jan J W Lagendijk1, Bas W Raaymakers1, Marco van Vulpen1
1Department of Radiotherapy, Imaging Division, UMC Utrecht, Utrecht, The Netherlands.
Seminars in Radiation Oncology
|June 17, 2014
Summary
Current radiotherapy image guidance is suboptimal for deep-seated tumors. A new integrated magnetic resonance imaging-linear accelerator system offers real-time imaging for improved precision and dose painting in challenging locations.
Area of Science:
- Medical Physics
- Radiation Oncology
- Diagnostic Imaging
Background:
- Image-guided radiotherapy (IGRT) systems face limitations in visualizing and accurately positioning patients for treatment of tumors in organs like the esophagus, pancreas, kidney, and rectum.
- Fiducial marker placement is difficult in these areas, and cone-beam computed tomography (CBCT) offers insufficient visualization, leading to geometrical uncertainties in daily patient setup.
- Organ motion due to breathing and filling introduces further interfraction and intrafraction uncertainties, complicating precise dose delivery.
Purpose of the Study:
- To present a novel integrated system combining magnetic resonance imaging (MRI) with a linear accelerator (LINAC) for real-time imaging during radiotherapy.
- To overcome the limitations of current IGRT systems for deep-seated tumors and address challenges in patient setup and motion management.
- To enable precise dose painting and optimize radiotherapy delivery for various tumor locations throughout the body.
Main Methods:
- Development and integration of a 1.5-Tesla (T) diagnostic quality MRI scanner with a 6-MV LINAC.
- The system is designed for real-time imaging of patients in the actual treatment position.
- Facilitates visualization of organs and tumors previously difficult to image with conventional IGRT.
Main Results:
- The integrated MRI-LINAC system provides real-time, diagnostic-quality imaging at the treatment position.
- It addresses the visualization and setup uncertainties associated with deep-seated tumors.
- The system supports precise targeting and dose optimization, including dose painting, for a wider range of anatomical locations.
Conclusions:
- The integrated 1.5-T MRI-LINAC system represents a significant advancement in image-guided radiotherapy.
- It enhances precision and accuracy for treating tumors in challenging locations, improving patient setup and motion management.
- This technology holds the potential to enable advanced radiotherapy techniques like dose painting for comprehensive tumor treatment.
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