Journal of X-Ray Science and Technology - Volume 31, issue 4

Authors: Zhang, Tiancheng | Almajidi, Yasir Q. | Awad, Sameer A. | Alhachami, Firas Rahi | Gatea, Maher Abdulfadhil | Kadhum, Wesam R.

Article Type: Research Article

Abstract: BACKGROUND: Several physical factors such as photon beam energy, electron beam energy, and dose rate may affect the dosimetric properties of polymer gel dosimeters. The photon beam energy and dose rate dependence of PASSAG gel dosimeter were previously evaluated. OBJECTIVE: This study aims to assess the dosimetric properties of the optimized PASSAG gel samples in various electron beam energies. METHODS: The optimized PASSAG gel samples are first fabricated and irradiated to various electron energies (5, 7, 10 and 12 MeV). Then, the response (R 2 ) and sensitivity of gel samples are analyzed by magnetic resonance imaging …technique at a dose range of 0 to 10 Gy, scanning room temperature range of 15 to 22 °C, and post-irradiation time range of 1 to 30 days. RESULTS: The R 2 -dose response and sensitivity of gel samples do not change under the evaluated electron beam energies (the differences are less than 5%). Furthermore, a dose resolution range of 11 to 38 cGy is obtained for the gel samples irradiated to different electron beam energies. Moreover, the findings show that the R 2 -dose response and sensitivity dependence of gel samples on electron beam energy varies over different scanning room temperatures and post-irradiation times. CONCLUSION: The dosimetric assessment of the optimized PASSAG gel samples provides the promising data for this dosimeter during electron beam radiotherapy. Show more

Keywords: Electron beam radiotherapy, PASSAG, MRI, Polymer gel dosimetry

DOI: 10.3233/XST-230073

Citation: Journal of X-Ray Science and Technology, vol. 31, no. 4, pp. 825-836, 2023

Authors: Kweon, Dae Cheol

Article Type: Research Article

Abstract: BACKGROUND: Due to the wide application of the cone beam computed tomography (CBCT) in clinical practice, it is important to assess radiation dose of CBCT more accurately and efficiently in different clinical applications. OBJECTIVE: This study aims to calculate effective and absorbed doses in CBCT measured in an anthropomorphic phantom using computer-based Monte Carlo (PCXMC) software, and to conduct comparative evaluations of MOSFET (metal– oxide– semiconductor field-effect transistor) and radiophotoluminescence glass dosimeters (RPLGD). METHODS: Effective and absorbed organ doses are compared with those obtained using MOSFET and RPLGD dosimetry in an anthropomorphic phantom given the same …exposure settings. Effective and absorbed organ doses from CBCT during scout and main projections are calculated using PCXMC and PCXMCRotation software, respectively. RESULTS: The mean effective dose from CBCT calculated using PCXMC software is 233.8μSv, while the doses calculated using dosimetry (MOSFET and RPLGD) are 266.67μSv and 268.78μSv, respectively. The X-ray source variation is 0.79%. The prescription limits based on the Friedman test for MOSFET and RPLGD pre-points (i.e., in an analytical analysis of diagnostic names in CBCT) are not statistically significant. The calculated correlation coefficient between MOSFET- and RPLGD-derived absorbed dose values with respect to a field of view CBCT parameter of 17×13.5 mm is r  = 0.8623. CONCLUSIONS: The study demonstrates that the PCXMC software may be used as an alternative to MOSFET and RPLGD dosimetry for effective and absorbed organ dose estimation in CBCT conducted with a large FOV in an anthropomorphic phantom. Show more

Keywords: Absorbed dose, cone beam CT, radiation dose, MOSFET, RPLGD

DOI: 10.3233/XST-230026

Citation: Journal of X-Ray Science and Technology, vol. 31, no. 4, pp. 837-852, 2023

Authors: Ma, Junmin

Article Type: Research Article

Abstract: OBJECTIVE: To explore the application value of digital tungsten-molybdenum double target three-dimensional positioning indwelling guide wire and guided surgical resection biopsy in the diagnosis of breast microcalcification. METHODS: A retrospective analysis of 168 patients with negative clinical palpation and molybdenum target X-ray examination found breast abnormalities were equally divided into two groups according to different surgical positioning methods. The control and observation group underwent gross positioning biopsy and digital tungsten-molybdenum dual-target three-dimensional positioning indwelling guide wire to guide surgical resection biopsy, respectively. The results of molybdenum target X-ray examination and the success rate of one-time complete resection of …the lesions were compared between the two groups, and the corresponding relationship between the pathological diagnosis results of the lesions after surgical resection and the performance of mammography in the observation group was compared. RESULTS: There was no significant difference in age and molybdenum target X-ray examination results between the two groups (P  > 0.05). General information is comparable; the success rate of one-time complete resection of lesions in the observation group was significantly higher than that in the control group (95.2% vs 78.6%, P  = 0.024). There were 34 cases of malignant lesions in the observation group, accounting for 40.5% (34/84), including 11 cases of invasive ductal carcinoma (64.7%), 50 cases of benign lesions, accounting for 59.5% (50/84), including 16 cases of breast lobular hyperplasia (32%), 18 cases of breast cystic hyperplasia (36%). CONCLUSION: In diagnosis of breast microcalcifications, surgical resection biopsy guided using digital tungsten-molybdenum double target three-dimensional positioning indwelling guide wire achieves high success rate and has advantages of high safety and accurate diagnosis. Thus, it has potential to play a greater role in early diagnosis of breast cancer and is worthy of clinical application. Show more

Keywords: Tungsten and molybdenum, microcalcification of breast, Three-dimensional stereoscopic, guide wire, target X-ray

DOI: 10.3233/XST-230039

Citation: Journal of X-Ray Science and Technology, vol. 31, no. 4, pp. 853-864, 2023