Kamanzi J D¹*, Md Akhtaruzzaman², Penabei Samafou³, Laurent Rangira¹, Sy Khady⁴, Uwitonze Emmanuel¹, Gahimano J B¹ and Bugingo Samuel⁵

¹Department of Radiation Oncology, Rwanda Cancer Centre, Kigali, Rwanda
²Department of Radiation Oncology, Evercare Hospital Chattogram, Bangladesh
³Faculty of Medicine and Health Sciences, University of Sherbrooke, Quebec, Canada
⁴Cheikh Anta Diop University, Dakar, Senegal
⁵Diagnostic Radiology Department, King Faisal Hospital, Rwanda

*Corresponding Author: Kamanzi J D, Department of Radiation Oncology, Rwanda Cancer Centre, Kigali, Rwanda.

Received: November 07, 2023; Published: December 26, 2023

Abstract

Aim: This study aimed to determine the degrees of accuracy that are practically achievable in dose measurement with reference to the international protocols and estimated the associated uncertainties.

Material and Method: Experiments were performed on Varian linac with 5 photon energies; 6, 10, 15 MV, and 6, 10, MV Flattening Filter Free. Tissue phantom ratio (TPR20,10), percent depth dose (%DD) were measured and calculated, while beam profile was only measured. Measurements for range of field sizes and depths were carried out in water with Farmer and Semiflex chambers.

Results: The measured TPR20,10 values were in agreement with calculations, where percentage error was found to be < 0.6% for all energies. The absorbed dose to water (Dw,Q) at zmax according to Task Group (TG)-51, and Technical Reports Series (TRS)-398 protocols was in good agreement with an average discrepancy of <0.2%. The observed discrepancies were thought to be associated with procedures and equipment used. The percentage difference between monitor units (MUs) delivered by linac and MUs calculated by Treatment Planning System (TPS) at 5 and 10 cm depths for various field sizes were found to be within ± 5% tolerance limit. The measured %DD are consistent with calculations from TPS. The relative standard uncertainty of Dw,Q at reference depth in water, was also found as ±<2.0%.

Conclusion: Overall, the results of measured parameters were in acceptable agreement as per recommended protocols, and measurements are consistent with calculations from TPS. This assisted to move forward with beam modelling of the TPS.

Keywords: Accuracy; Uncertainties; Photon; Dosimetry; Protocols

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Citation

Citation: Kamanzi J D., et al. “Practically Achievable Accuracy and Uncertainties Estimation in Radiation Dose Measurement with Different Protocols". Acta Scientific Clinical Case Reports 5.1 (2024): 56-62.

Copyright

Copyright: © 2024 Kamanzi J D., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.