Journal of Research in Applied and Basic Medical Sciences
Journal of Research in Applied and Basic Medical Sciences
Medical Sciences
http://ijrabms.umsu.ac.ir
1
admin
2717-0098
8
10.61186/rabms
14
8888
13
en
jalali
1400
9
1
gregorian
2021
12
1
7
3
online
1
fulltext
en
Analytical Formula for the total scatter factor of the Small Radiation Field Size
Analytical Formula for the total scatter factor of the Small Radiation Field Size
تخصصي
Special
پژوهشي
orginal article
<strong><em>Background & Aims</em></strong>: We present an analytical formula (AF) to calculate the total scatter factor of the MLC-shaped small radiation beams.<br>
<strong><em>Materials & Methods</em></strong><em>:</em> Pinpoint, Semiflex, and Farmer ion chambers were used for MLC/Jaw-shaped fields extending from (10x10 cm<sup>2</sup>) down to (1x1 cm<sup>2</sup>). The total scatters factor, beam profiles, and penumbra was investigated for MLC/Jaw-shaped beams.<br>
<strong><em>Results</em></strong><em>:</em> We found that the total scatters factor and the penumbra was clearly higher for MLC-shaped beams due to the MLC leakage, which becomes more and more significant for the small fields. The Analytical Formula was introduced as a least-square fit equation and verified against to measure data. The maximum deviation at small field size (< 4 cm<sup>2</sup>) was within 3.6% and 43.9% from both MLC and Jaw-shaped beams, respectively.<br>
<strong><em>Conclusion</em></strong>: Our analytical formula shows a very good agreement with measured data at a large field size (> 4 cm<sup>2</sup>), and had small deviation with MLC-shaped small field size, emphasizing that our analytical formula is valid and reasonably good for the total scatters factor calculation of the MLC-shaped beams, especially the ultra-small field size.
Small field dosimetry, Total Scatter Factor, Analytical Formula of Small Radiation Field Size
152
160
http://ijrabms.umsu.ac.ir/browse.php?a_code=A-10-164-1&slc_lang=en&sid=1
Saed
Al Atawneh
saed.al-atawneh@atomki.hu
10031947532846001246
10031947532846001246
Yes
Department of Radiation Oncology, King Hussein Cancer Center, Amman, Jordan