Monte Carlo simulations and radiation dosimetry measurements of (142)Pr capillary tube-based radioactive implant (CTRI): A new structure for brachytherapy sources - Abstract

OBJECTIVE: Previously, a promising β-emitting praseodymium-142 glass seed was proposed for brachytherapy of prostate cancer.

In accordance with the previous study, a 142Pr capillary tube-based radioactive implant (CTRI) was suggested as a source with a new structure to enhance application of β-emitting radioisotopes such as 142Pr in brachytherapy.

METHODS: Praseodymium oxide powder was encapsulated in a glass capillary tube. Then, a thin and flexible fluorinated ethylene propylene Teflon(®) layer sealed the capillary tube. The source was activated in the Tehran Research Reactor by the 141Pr(n,γ) 142Pr reaction. Measurements of the dosimetric parameters were performed using GafChromic(®) radiochromic film. In addition, the dose rate distribution of 142Pr CTRI was calculated by modeling 142Pr source in a water phantom using Monte Carlo N-Particle Transport (MCNP5) Code.

RESULTS: The active source was unreactive and did not leak in water. In comparison with the earlier proposed 142Pr seed, the suggested source showed similar desirable dosimetric characteristics. Moreover, the 142Pr CTRI production procedure may be technically and economically more feasible. The mass of praseodymium in CTRI structure could be greater than that of the 142Pr glass seed; therefore, the required irradiation time and the neutron flux could be reduced.

CONCLUSION: A 142Pr CTRI was proposed for brachytherapy of prostate cancer. The dosimetric calculations by the experimental measurements and Monte Carlo simulation were performed to fulfill the requirements according to the American Association of Physicists in Medicine recommendations before the clinical use of new brachytherapy sources. The characteristics of the suggested source were compared with those of the previously proposed 142Pr glass seed.

Written by:
Bakht MK, Sadeghi M, Ahmadi SJ, Haddadi A, Sadjadi SS, Tenreiro C.   Are you the author?
Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University, 1454696111, Tehran, Iran.

Reference: Ann Nucl Med. 2013 Feb 5. Epub ahead of print.
doi: 10.1007/s12149-013-0683-y


PubMed Abstract
PMID: 23381937

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