RAMACOS FARDELA1,*, EGA SEPTRYAN CANDRA1, DIAN
MILVITA1, DEDI MARDIANSYAH1, RIDWAN2 &
FIQI DIYONA3
1Department
of Physics, Faculty of Mathematics and Natural Science, Universitas Andalas,
Sumatera Barat, 25163, Indonesia
2Healthineers
Company, Forchheim-91301, Germany
3Medical Physics,
Radiotherapy Installation, Unand Hospital, Padang, 25176, Indonesia
Diserahkan: 26 Disember 2024/Diterima:
23 Jun 2025
Abstract
Cancer
treatment using ionizing radiation is known to cause damage to healthy tissue
around the target. Therefore, this study aimed to measure the dose in the area
around the cancer target to ensure the amount received by the patient does not
exceed the specified tolerance limit. Measurements
were performed using a Farmer-type ionization chamber detector on a phantom
slab. The variations in the field area used were 5 × 5 cm2 and 10 ×
10 cm2 at depths of 1.5 cm, 4 cm, 6 cm, 8 cm, and 10 cm, as well as
a distance of 3 cm, 5 cm, 7 cm, 10 cm, and 15 cm outside the radiation field.
The dose value was measured based on the IAEA TRS No.398 protocol. The results showed that the
percentage of the dose decreased below 10% at a distance of 5 cm for a field
area of 5 × 5 cm2. Meanwhile, for a field area of 10 × 10 cm2,
the percentage of the dose decreased below 10% after passing a distance of 7 cm
from the edge of the radiation field. Based on the results, the percentage of
the measured dose was greater for the enlarged depth. Areas outside the cancer target still
receive unneeded radiation doses. The value of the dose received depends on the
energy used, the size of the field, and the distance from the edge of the field.
Keywords: Cancer;
depth; dose; edge distance; LINAC
Abstrak
Rawatan kanser menggunakan sinaran pengionan
diketahui boleh menyebabkan kerosakan pada tisu sihat di sekeliling sasaran.
Justeru, penyelidikan ini bertujuan untuk mengukur dos di kawasan sekitar
sasaran kanser bagi memastikan jumlah yang diterima pesakit tidak melebihi had
toleransi yang ditetapkan. Pengukuran dilakukan menggunakan pengesan kebuk
pengionan jenis Petani pada papak fantom. Variasi luas lapangan yang digunakan
ialah 5 × 5 cm2 dan 10 × 10 cm2 pada kedalaman 1.5 cm, 4
cm, 6 cm, 8 cm dan 10 cm serta jarak 3 cm, 5 cm, 7 cm, 10 cm dan 15 cm di luar
medan sinaran. Nilai dos diukur berdasarkan protokol IAEA TRS No. 398.
Keputusan menunjukkan bahawa peratusan dos menurun di bawah 10% pada jarak 5 cm
untuk kawasan medan seluas 5 × 5 cm2. Manakala, bagi kawasan medan
seluas 10 × 10 cm2, peratusan dos menurun di bawah 10% selepas
melepasi jarak 7 cm dari tepi medan sinaran. Berdasarkan keputusan, peratusan
dos yang diukur adalah lebih besar untuk kedalaman yang diperbesarkan. Kawasan
di luar sasaran kanser masih menerima dos sinaran yang tidak diperlukan. Nilai
dos yang diterima bergantung pada tenaga yang digunakan, saiz medan dan jarak
dari tepi medan.
Kata kunci: Dos; jarak tepi; kanser;
kedalaman; LINAC
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*Pengarang untuk surat-menyurat; email: ramacosfardela@sci.unand.ac.id