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Comparison of dosimetric properties among four commercial multi-detector computed tomography scanners
| Content Provider | Scilit |
|---|---|
| Author | Ohno, Takeshi Araki, Fujio Onizuka, Ryota Hatemura, Masahiro Shimonobou, Toshiaki Sakamoto, Takashi Okumura, Shuichiro Ideguchi, Daichi Honda, Keiichi Kawata, Kenji |
| Copyright Year | 2017 |
| Description | Journal: Physica Medica This study compared dosimetric properties among four commercial multi-detector CT (MDCT) scanners. The X-ray beam characteristics were obtained from photon intensity attenuation curves of aluminum and off-center ratio (OCR) profiles in air, which were measured with four commercial MDCT scanners. The absorbed dose for MDCT scanners was evaluated with Farmer ionization chamber measurements at the center and four peripheral points in the body- and head-type cylindrical water phantoms. Measured collected charge was converted to absorbed dose using a$ ^{60}$Co absorbed dose-to-water calibration factor and Monte Carlo (MC)-calculated correction factors. Four MDCT scanners were modeled to correspond with measured X-ray beam characteristics using GMctdospp (IMPS, Germany) software. Al half-value layers (Al-HVLs) with a body-bowtie filter determined from measured Al-attenuation curves ranged 7.2‒9.1mm at 120kVp and 6.1‒8.0mm at 100kVp. MC-calculated Al-HVLs and OCRs in air were in acceptable agreement within 0.5mm and 5% of measured values, respectively. The percentage difference between nominal and actual beam width was greater with decreasing collimation width. The absorbed doses for MDCT scanners at 120kVp ranged 5.1‒7.1mGy and 10.8‒17.5mGy per 100mAs at the center in the body- and head-type water phantoms, respectively. Measured doses at four peripheral points were within 5% agreement of MC-calculated values. The absorbed dose at the center in both water phantoms increased with decreasing Al-HVL for the same charge on the focus. In this study the X-ray beam characteristics and the absorbed dose were measured and compared with calculated values for four MDCT scanners. |
| Related Links | http://www.physicamedica.com/article/S1120179717300418/pdf |
| Ending Page | 58 |
| Page Count | 9 |
| Starting Page | 50 |
| ISSN | 11201797 |
| DOI | 10.1016/j.ejmp.2017.02.007 |
| Journal | Physica Medica |
| Volume Number | 35 |
| Language | English |
| Publisher | Elsevier BV |
| Publisher Date | 2017-02-19 |
| Access Restriction | Open |
| Subject Keyword | Journal: Physica Medica Radiology, Nuclear Medicine and Imaging Multi-detector Ct Monte Carlo Technique Ionization Chamber Measurement Absorbed Dose |
| Content Type | Text |
| Resource Type | Article |
| Subject | Radiology, Nuclear Medicine and Imaging Physics and Astronomy Biophysics |
