Plastic scintillators are playing an increasing role in oncology medical physics, particularly in radiation dosimetry for external beam therapy, brachytherapy, and proton therapy. Their advantages, such as real-time response, water-equivalence, and resistance to radiation damage, make them well-suited for precise dose measurements in clinical applications.
Applications in Oncology Medical Physics
(a) External Beam Radiation Therapy (EBRT) Dosimetry
- Plastic scintillators are used to measure radiation dose distributions in photon and electron therapy. Their small size allows for measurements in small radiation fields, which is essential for Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT).
(b) Proton and Heavy Ion Therapy Dosimetry
- Plastic scintillators are highly effective in Bragg peak measurement for proton and ion beam therapy, where precise dose deposition is crucial for tumor targeting.
(c) Brachytherapy Source Dosimetry
- Plastic scintillators are used for high-dose-rate (HDR) brachytherapy QA, where accurate dose measurements near the source are essential.
(d) Real-Time In Vivo Dosimetry for Patient Safety
Plastic scintillators provide immediate feedback on radiation doses during treatment, helping to:
- Detect dose discrepancies in real-time.
- Ensure patient-specific quality assurance (PSQA).
- Prevent overexposure in sensitive organs.
Challenges and Future Developments
Challenges
- Cerenkov Radiation Interference: At high-energy photon beams, unwanted Cerenkov light is generated, requiring spectral filtering or correction algorithms.
- Calibration Complexity: Plastic scintillators require careful calibration due to their light output dependence on radiation type and energy.
- Signal Attenuation in Optical Fibers: Long fiber-optic delivery systems may cause signal loss, affecting measurement accuracy.
Future Developments
- Advanced Optical Filtering: Reducing Cerenkov noise to improve signal purity.
- Improved Spectral Response Scintillators: Enhanced dopants to optimize light yield and emission properties.
- Miniaturized Scintillators: For ultra-high spatial resolution applications in micro-dosimetry.
- Integration with AI and Machine Learning: To enhance real-time dose analysis and treatment adaptation.
Plastic scintillators are revolutionizing oncology medical physics, providing real-time, high-precision dosimetry for advanced radiation therapy techniques. As their technology continues to improve, they will play a crucial role in personalized radiation treatment, enhancing patient safety and treatment accuracy.