DOSIMETRIC STUDY OF MANDIBLE EXAMINATIONS PERFORMED WITH THREE CONE-BEAM COMPUTED TOMOGRAPHY SCANNERS

作者：Khoury Helen J^*; Andrade Marcos E; Araujo Max Well; Brasileiro Izabela V; Kramer Richard; Huda Amir

来源：Radiation Protection Dosimetry, 2015, 165(1-4): 162-165.

DOI：10.1093/rpd/ncv058

The objective of this work was to evaluate the air kerma-area product (P-KA) and the skin absorbed dose in the region of the eyes, salivary glands and thyroid of the patient from mandible examinations performed with three cone-beam computed tomography (CBCT) scanners, i.e. i-CAT classic, Gendex CB-500 and PreXion 3D. For the dosimetric evaluation, an anthropomorphic head phantom (model RS-250) was used to simulate an adult patient. The CBCT examinations were performed using standard and high-resolution protocols for mandible acquisitions for adult patients. During the phantom's exposure, the P-KA was measured using an ionising chamber and the absorbed doses to the skin in the region of the eyes, thyroid and salivary glands were estimated using thermoluminescence dosemeters (TLDs) positioned on the phantom's surface. The P-KA values estimated with the CBCT scanners varied from 26 to 138 mu Gy m(2). Skin absorbed doses in the region of the eyes varied from 0.07 to 0.34 mGy; at the parotid glands, from 1.31 to 5.93 mGy; at the submandibular glands, from 1.41 to 6.86 mGy; and at the thyroid, from 0.18 to 2.45 mGy. P-KA and absorbed doses showed the highest values for the PreXion 3D scanner due to the use of the continuous exposure mode and a high current-time product.

• 出版日期2015-7