Author: Ziyad ABUBAKR ALHAREESHi, Ibtihaj Yussef Alhodire, Najla Sobhi Bin Shehima, Aram Mufteh A Genaw 👨🔬
Affiliation: Tripoli university hospital 🌍
Purpose:
This research investigates the recombination and polarity correcting factors for CC04, CC13, FC65P, FC65G, Razor, and PP05 ionization chambers to improve radiation dosimetry accuracy. Understanding these variances is critical to enhancing the accuracy of dose assessments and guaranteeing appropriate patient treatment in clinical radiation situations. This research reviews the effects of recombination and polarity in cylindrical and parallel plate ionization chambers, as well as the impact of varying photon and electron energies on these effects.
Methods:
Both Krecombination and Kpolarity were measured with all chambers mentioned in the purpose, with Elekta synergy energies of:
6, 10MV Photon.
4, 6, 8, 10, 12, 15Mev electron, except FC65G and FC65P were measured in electron energy above 8Mev.
Krecombination was determined using the two-voltage method and Kpolarity was measured by reversing ionization chamber polarity.
The data analysis was performed using descriptive statistics analysis employed to evaluate variations of each energy Krecombination and Kpolarity from the average Krecombination and Kpolarity.
Results:
Krecombination: CC04:1.0031±0.0004, CC13:1.0071± 0.0016, FC65P:1.0031± 0.0087, FC65G:0.99661± 0.0128, Razor:1.0092± 0.0013, PP05:1.0033± 0.0009.
Kpolarity: CC04: 0.9974± 0.0034, CC13:0.9989± 0.0035, FC65P:0.9998±0.0004, FC65G:1.0263±0.0004, Razor:0.9879± 0.0127, PP05:0.9957± 0.0036.
Conclusion:
The chamber that was least affected by the Recombination effect was CC04, followed by FC65G and then PPC05. On the other hand, the least chamber affected by the polarity effect was FC65P, followed by CC13 and then CC04. The measured chamber most affected by Recombination was Razor, while the chamber most affected by polarity was FC65G and then Razor.
Regarding the energy impact on recombination and polarity effect of the chamber, it was found that the Krecombination for CC04 was the least affected by energy, while the Kpolarity for FC65G showed minimal impact by energy.
It is important to note that the FC65G was out of calibration; therefore, the findings from the research cannot be generalized.