Click here to

Session: Beam Measurements and Commissioning [Return to Session]

A Novel Multi-Headed Scintillation Detector for Fast and Efficient Dose Measurements at Multiple Locations Simultaneously

B Lessard1,2*, Y Lechasseur3, S Lambert-girard3, F Therriault-Proulx3, L Beaulieu1,2, L Archambault1,2, (1) Departement de physique, genie physique et optique, and Centre de recherche sur le cancer, Universite Laval, Quebec, CA (2) CHU de Quebec - Universite Laval and CRCHU de Quebec, Quebec, CA (3) Medscint inc., Quebec, CA


SU-H430-IePD-F4-4 (Sunday, 7/10/2022) 4:30 PM - 5:00 PM [Eastern Time (GMT-4)]

Exhibit Hall | Forum 4

Purpose: To develop and quantify the performances of a novel multi-point scintillation detector (mPSD) having multiple heads connected to the same optical line, allowing real-time dose measurements simultaneously at 3 positions in non-contiguous space.

Methods: The mPSD is composed of a single optical line connected to 3 optical fibers, each having a different scintillator at their tip (i.e. the detector heads). The mPSD is built using 1 mm plastic PMMA fiber to guide the light emitted by the scintillators, the latters having a diameter and a length of 1 mm. To verify the performances of this detector, it is irradiated under a 6 MV photon beam delivered by a Varian TrueBeam linear accelerator, and dose measurements are performed with the Hyperscint dosimetry research platform HS-RP 200 (Medscint, Quebec City, Canada). Each head is calibrated as a single point PSD. Dose profile measurements are acquired for each head individually in a solid water phantom and compared to the profiles obtained when the 3 heads are irradiated simultaneously.

Results: For dose profile measurements performed with a 5x5 cm² photon field, the absolute difference between the profiles acquired one head at a time and those acquired with the 3 heads irradiated at the same time varies between 0% and 34%, but in the plateau region, the difference lies within 3%.

Conclusion: The new multi-headed mPSD developed in this study provides many advantages compared to previous mPSDs, including the greater versatility relative to the positioning of the scintillators. Also, the farthest scintillator in an in-line mPSD for example has a lower signal caused by the presence of the other scintillators in the same optical line, which is not a problem with the new multi-headed detector. Further experimental validations will be conducted in the future with different multi-headed mPSDs to optimize this detector.

Funding Support, Disclosures, and Conflict of Interest: This project is funded by the Natural Sciences and Engineering Research Council of Canada (NSERC).


Scintillators, Photon Detectors, Optical Dosimetry


TH- Radiation Dose Measurement Devices: scintillators

Contact Email