| Autor: |
Rajeshree Pai, Deepak D. Deshpande, P. K. Dash Sharma, Swamidas V. Jamema, Rajesh A Kinhikar |
| Rok vydání: |
2009 |
| Předmět: |
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| Zdroj: |
Radiation Measurements. 44:188-192 |
| ISSN: |
1350-4487 |
| Popis: |
A vault as per government-regulation compliance with adequate shielding needs was designed and constructed for Hi-Art II Tomotherapy machine being the first in India. Radiation measurements around this Tomotherapy treatment vault were carried out to check the shielding adequacy of the source housing and the vault. It was mandatory to get this un-conventional machine “Type Approved” by Atomic Energy Regulatory Board (AERB) in India. The aim of this paper was to report on the radiation levels measured during the radiation survey carried out for this machine. The radiation levels in and around the vault were measured for stationary as well as rotational treatment procedures with the largest open field size (5 cm × 40 cm) at the isocenter with and without scattering medium. The survey was performed at three locations near each wall surrounding the vault as well. The leakage radiation from the source housing was measured both in the patient plane outside the treatment field and one meter distance from the source outside the patient plane. The radiation levels both for stationary as well as rotational procedures were within 1 mR/h. No significance difference was observed in the radiation levels measured for rotational procedures with and without scattering medium. The leakage radiation in the patient plane was found to be 0.04% (Tolerance 0.2%), while the head leakage was 0.007% (Tolerance 0.5%) of the dose rate at the isocenter. The treatment delivery with Tomotherapy does play safe radiation levels around the installation layout and also passes the leakage criteria as well. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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