A scintillator-based range telescope for particle therapy.

Area of Science:

• Medical Physics
• Particle Therapy
• Radiation Detection

Background:

• Particle therapy centers require precise beam monitoring for quality assurance.
• Accurate measurement of beam range is critical for effective cancer treatment.
• Existing detectors can suffer from optical artifacts and alignment issues.

Purpose of the Study:

• To present a novel range telescope for particle therapy beam range quality assurance.
• To evaluate the performance, accuracy, and robustness of the developed detector prototype.
• To investigate the potential for measuring ion beam ranges.

Main Methods:

• A compact range telescope was constructed using 49 plastic scintillator sheets (2-3 mm thick) read out by a large-scale CMOS sensor.
• A novel Bragg curve model incorporating scintillator quenching effects was used for range reconstruction.
• Detector performance was characterized at two leading particle therapy facilities (HIT and CCC).

Main Results:

• The detector achieved a maximum range difference of 0.41 mm at 310 mm proton beam range, dominated by alignment uncertainties.
• Water-equivalent thickness of PMMA degrader blocks was reconstructed within ± 0.1 mm.
• The range reconstruction algorithm demonstrated robustness after 6,300 Gy peak dose, with negligible impact from beam spot size or position variations.

Conclusions:

• The novel range telescope offers a compact and accurate solution for proton beam range quality assurance in particle therapy.
• The detector design and reconstruction algorithm are robust against radiation and minor beam variations.
• The technology shows promise for extending range measurements to ion beams.