Imaging dose assessment for IGRT in particle beam therapy
Elisabeth Steiner1, Markus Stock, Boris Kostresevic
1Department of Radiation Oncology, Medical University of Vienna, Austria; Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Austria.
Summary
Image-guided radiation therapy (IGRT) for lung cancer uses imaging, increasing patient dose. Planar kV or stereoscopic imaging yields low doses (≈1 mGy), while volumetric imaging is higher, but optimization can reduce overall exposure.
Area of Science:
- Medical Physics
- Radiation Oncology
- Radiological Imaging
Background:
- Image-guided advanced photon and particle beam treatments offer improved lung cancer therapy.
- Extensive use of imaging in these treatments significantly increases the overall patient radiation dose.
- Accurate dose assessment is crucial for optimizing treatment protocols.
Purpose of the Study:
- To determine and compare the patient organ at risk (OAR) imaging dose for various image-guided radiation therapy (IGRT) solutions.
- To evaluate imaging doses across different photon and particle beam therapy centers.
- To identify strategies for minimizing radiation exposure during lung cancer treatment.
Main Methods:
- Dosimetric measurements were conducted using thermoluminescent dosimeters (TLDs) in an Alderson phantom.
- Clinically relevant imaging protocols including kV imaging, stereoscopic imaging, CT scout, fluoroscopy, CT, 4D-CT, and CBCT were investigated.
- Imaging doses were assessed for specific lung tumor irradiation protocols at multiple radiotherapy centers.
Main Results:
- Organ at risk (OAR) doses varied based on imaging modality and OAR location.
- Planar and stereoscopic imaging resulted in low doses (approximately 1 mGy).
- Volumetric imaging doses ranged from 10-50 mGy, with one CBCT device showing lower doses; prolonged fluoroscopy yielded the highest skin dose (up to 150 mGy).
Conclusions:
- Low-dose modalities like planar kV or stereoscopic imaging are suitable for minimizing patient exposure.
- Strategies such as imaging moving targets during irradiation, employing low-dose protocols, and protocol optimization can substantially reduce the overall imaging dose.
- Careful selection and optimization of IGRT protocols are essential for safe and effective lung cancer treatment.
More Related Videos
Related Concept Videos
01:25Imaging Studies II: Positron Emission Tomography and Scintigraphy
863
Positron Emission Tomography (PET) is a medical imaging technique that provides crucial insights into the body's physiological functions at a molecular level. It is an indispensable resource for diagnosing, staging, and monitoring various illnesses, notably cancer, neurological disorders, and cardiovascular conditions.
Fundamental Principles of PET
Fundamental Principles of PET
863
02:59Biological Effects of Radiation
15.5K
All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break chemical bonds, or ionize molecules. The most serious biological damage results when these radioactive emissions fragment or ionize molecules. For example, α and β particles emitted from nuclear decay reactions possess much higher energies than ordinary chemical bond energies. When these particles strike and penetrate matter, they...
15.5K