1
|
Girsa D, Kremenova K, Lukavsky J, Sukupova L, Malikova H. Comparison of dose length product and image quality of a biphasic whole-body polytrauma CT protocol with and without the automatic tube voltage selection. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2024. [PMID: 38445394 DOI: 10.5507/bp.2024.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024] Open
Abstract
BACKGROUND AND AIMS A significant source of man-made radiation is now linked to medical devices especially X-ray imaging based ones like CT scans which expose the body to cumulative ionizing radiation and thus attendant cancer risks. The aim of this study was to determine whether using a combination of Automatic Tube Current Modulation (ATCM) and Automatic Tube Voltage Selection (ATVS) during two-phase whole-body CT (2PWBCT) examinations would reduce the radiation dose while preserving the image quality. PATIENTS AND METHODS This was a prospective, observational, single-centre study of 127 adult patients who had undergone the 2PWBCT polytraumatic protocol. All were examined on a Somatom Drive scanner (Siemens). The patients were divided into two groups: ATCM only (42 patients) and ATCM +ATVS (85 patients). Patients' arm positions during examination and the examination dose length product (DLP) values were recorded, as well the standard deviations (SD) of the density in reference areas on CT scans for the image quality assessment. The DLP values and image quality in the groups were compared using ANOVA. RESULTS Mean Total DLP (in mGy*cm): ATCM only: 3337 +/-797, ATCM+ATVS: 3402 +/-830; P=0.674. No effect of arm position (P=0.586). Mean density SD values in reference areas (in HU) in ATCM only: 49 +/-45, 15 +/-6, 9 +/-2, 12 +/-4, 10 +/-3, in ATCM+ATVS: 48 +/-45, 17 +/-6, 11 +/-3, 15 +/-6, 12 +/-4. SD values was higher in ATCM+ATVS group (P<0.001). CONCLUSION Combination of ATVS and ATCM in polytraumatic 2PWBCT leads to no significant radiation load reduction compared with ATCM only but does lead to a slight degradation of image quality. The radiation load is significantly reduced if the patient has their arms behind the head when scanning, regardless of the activation of ATVS.
Collapse
Affiliation(s)
- David Girsa
- Department of Radiology and Nuclear Medicine, Third Faculty of Medicine, Charles University in Prague and Faculty Hospital Kralovske Vinohrady; Second Faculty of Medicine, Charles University in Prague, Czech Republic
| | - Karin Kremenova
- Department of Radiology and Nuclear Medicine, Third Faculty of Medicine, Charles University in Prague and Faculty Hospital Kralovske Vinohrady, Prague, Czech Republic
| | - Jiri Lukavsky
- Institute of Psychology, Czech Academy of Sciences, 110 00 Prague, Czech Republic; Department of Psychology, Faculty of Arts, Charles University in Prague, Czech Republic
| | - Lucie Sukupova
- Director's Department, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Hana Malikova
- Department of Radiology and Nuclear Medicine, Third Faculty of Medicine, Charles University in Prague and Faculty Hospital Kralovske Vinohrady; Second Faculty of Medicine, Charles University in Prague, Czech Republic
| |
Collapse
|
2
|
Aly A, Ebrahimian S, Kharita MH, Heidous M, Ashruf MZ, Kumar D, Kalra MK, Al Naemi HM. Effect of technologist and patient attributes on centering for body CT examinations: Influence of cultural and ethnic factors. PLoS One 2022; 17:e0273227. [PMID: 35984837 PMCID: PMC9390905 DOI: 10.1371/journal.pone.0273227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 07/21/2022] [Indexed: 11/19/2022] Open
Abstract
There are no published data on the effect of patient and technologist gender and ethnicity attributes on off-centering in CT. Therefore, we assessed the impact of patient and technologist variations on off-centering patients undergoing body CT. With institutional review board approval, our retrospective study included 1000 consecutive adult patients (age ranged 22–96 years; 756 males: 244 females) who underwent chest or abdomen CT examinations. We recorded patient (age, gender, nationality, body weight, height,), technologist gender, and scan-related (scanner vendor, body region imaged, scan length, CT dose index volume, dose length product) information. Lateral and anteroposterior (AP) diameters were recorded to calculate effective diameter and size-specific dose estimate (SSDE). Off-centering represented the distance between the anterior-posterior centers of the scan field of view and the patient at the level of carina (for chest CT) and iliac crest (for abdomen CT). About 76% of the patients (760/1000) were off-centered with greater off-centering for chest (22 mm) than for abdomen (15 mm). Although ethnicity or patient gender was not a significant determinant of off-centering, technologist-patient gender mismatch was associated with a significantly greater frequency of off-centering (p<0.001). Off-centering below the gantry isocenter was twice as common as off-centering above the gantry isocenter (p<0.001). The latter occurred more frequently in larger patients and was associated with higher radiation doses than those centered below the isocenter (p<0.001). Technologists’ years of experience and patient factors profoundly affect the presence and extent of off-centering for both chest and abdomen CTs. Larger patients are more often off-centered than smaller patients.
Collapse
Affiliation(s)
- Antar Aly
- Hamad Medical Corporation, Doha, Qatar
- * E-mail:
| | - Shadi Ebrahimian
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | | | | | | | | | - Mannudeep K. Kalra
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | | |
Collapse
|
3
|
Zhao Y, Li D, Liu Z, Geng X, Zhang T, Xu Y. Comparison of image quality and radiation dose using different pre-ASiR-V and post-ASiR-V levels in coronary computed tomography angiography. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2021; 29:125-134. [PMID: 33164983 DOI: 10.3233/xst-200754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
OBJECTIVE To determine the optimal pre-adaptive and post-adaptive level statistical iterative reconstruction V (ASiR-V) for improving image quality and reducing radiation dose in coronary computed tomography angiography (CCTA). METHODS The study was divided into two parts. In part I, 150 patients for CCTA were prospectively enrolled and randomly divided into 5 groups (A, B, C, D, and E) with progressive scanning from 40% to 80% pre-ASiR-V with 10% intervals and reconstructing with 70% post-ASiR-V. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was assessed using a 5-point scale. The CT dose index volume (CTDIvol) and dose-length product (DLP) of each patient were recorded and the effective radiation dose (ED) was calculated after statistical analysis by optimizing for the best pre-ASiR-V value with the lowest radiation dose while maintaining overall image quality. In part II, the images were reconstructed with the recommended optimal pre-ASiR-V values in part I (D group) and 40%-90% of post-ASiR-V. The reconstruction group (D group) was divided into 6 subgroups (interval 10%, D0:40% post-ASiR-V, D1:50% post - ASiR-V, D2:60% post-ASiR-V, D3:70% post-ASiR-V, D4:80% post-ASiR-V, and D5:90% post-ASiR-V).The SNR and CNR of D0-D5 subgroups were calculated and analyzed using one-way analysis of variance, and the consistency of the subjective scores used the k test. RESULTS There was no significant difference in the SNRs, CNRs, and image quality scores among A, B, C, and D groups (P > 0.05). The SNR, CNR, and image quality scores of the E group were lower than those of the A, B, C, and D groups (P < 0.05). The mean EDs in the B, C, and D groups were reduced by 7.01%, 13.37%, and 18.87%, respectively, when compared with that of the A group. The SNR and CNR of the D4-D5 subgroups were higher than the D0-D3 subgroups, and the image quality scores of the D4 subgroups were higher than the other subgroups (P < 0.05). CONCLUSION The wide-detector combined with 70% pre-ASiR-V and 80% post-ASiR-V significantly reduces the radiation dose of CCTA while maintaining overall image quality as compared with the manufacture's recommendation of 40% pre-ASiR-V.
Collapse
Affiliation(s)
- Yongxia Zhao
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, China
| | - Dongxue Li
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, China
| | - Zhichao Liu
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, China
| | - Xue Geng
- Department of Radiology, Baoding No. 2 Hospital, Baoding, China
| | - Tianle Zhang
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, China
| | - Yize Xu
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, China
| |
Collapse
|
4
|
Zhao Y, Geng X, Li D, Zhang T, Xu Y. Application of full-field organ dose modulation on cervical- thoraco-abdominopelvic contrast-enhanced computed tomography. Jpn J Radiol 2020; 39:254-260. [PMID: 33113053 DOI: 10.1007/s11604-020-01056-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 10/09/2020] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND OBJECTIVE To study the radiation dose and image quality on the use of full-field organ dose modulation (ODM) on cervical-thoracic-abdominal-pelvic contrast-enhanced computed tomography (CT) scanning on female chemotherapy patients. METHODS Eighty female chemotherapy patients undergoing cervical-thoracic-abdominal-pelvic contrast-enhanced CT were prospectively enrolled and randomly divided into two groups: group A and group B, each with 40 patients. Full-field ODM technique was used on group A and regular scanning patterns were used on group B. We calculated and recorded the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective scores, mean tube currents of the anterior, left, posterior, and right aspects of the thyroid, breast, and ovary layers of all the images. The CT dose index volume (CTDIvol) and dose-length product (DLP) of each patient were recorded and the effective radiation dose (ED) was calculated. The above data were statistically analyzed. RESULTS There were no statistically significant differences in the SNR, CNR, and image quality scores of the thyroid, breast, and ovary layers of groups A and B during the arterial and venous phases (P > 0.05). The tube current on the anterior, left, posterior, and right aspects of the thyroid, breast, and ovary layers during the arterial and venous phases (thyroid: 324.46 ± 53.2 and 327.97 ± 61.34; breast: 243.13 ± 50.04 and 248.32 ± 60.33; ovary: 332.28 ± 71.50 and 339.78 ± 76.69; respectively) of group A were (statistically) significantly lower than those of group B (thyroid: 407.60 ± 96.81 and 402.73 ± 90.15; breast: 313.00 ± 106.68 and 315.20 ± 106.73; ovary: 457.78 ± 106.56 and 459.63 ± 106.27; respectively) (P < 0.05). The respective mean CTDIvol and DLP in group A were 22% and 24% lower than those of group B. The mean EDs of the neck, chest, and abdominal-pelvic region in group A were 19.3%, 21.4%, and 26.4% lower than those of group B, respectively (P < 0.05). CONCLUSION The use of ODM can reduce radiation dose of female chemotherapy patients undergoing cervical-thoracic-abdominal-pelvic contrast-enhanced CT, especially radiation-sensitive organs, while maintaining overall image quality.
Collapse
Affiliation(s)
- Yongxia Zhao
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, 071000, People's Republic of China.
| | - Xue Geng
- Department of Radiology, Baoding No.2 hospital, Baoding, 071000, People's Republic of China
| | - Dongxue Li
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, 071000, People's Republic of China
| | - Tianle Zhang
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, 071000, People's Republic of China
| | - Yize Xu
- Department of Radiology, The Affiliated Hospital of Hebei University, Baoding, 071000, People's Republic of China
| |
Collapse
|
5
|
Best practice for the nuclear medicine technologist in CT-based attenuation correction and calcium score for nuclear cardiology. Eur J Hybrid Imaging 2020; 4:11. [PMID: 34191150 PMCID: PMC8218053 DOI: 10.1186/s41824-020-00080-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 06/16/2020] [Indexed: 12/12/2022] Open
Abstract
The use of hybrid systems is increasingly growing in Europe and this is progressively important for the final result of diagnostic tests. As an integral part of the hybrid imaging system, computed tomography (CT) plays a crucial role in myocardial perfusion imaging diagnostics. Throughout Europe, a variety of equipment is available and also different university curricula of the nuclear medicine technologist are observed. Hence, the Technologist Committee of the European Association of Nuclear Medicine proposes to identify, through a bibliographic review, the recommendations for best practice in computed tomography applied to attenuation correction and calcium score in myocardial perfusion imaging, which courses in the set of knowledge, skills, and competencies for nuclear medicine technologists. This document aims at providing recommendations for CT acquisition protocols and CT image optimization in nuclear cardiology.
Collapse
|
6
|
Chen Y, Liu Z, Li M, Yu Y, Jia Y, Ma G, Hu Z, Wei D, Li D, He T. Reducing both radiation and contrast doses in coronary CT angiography in lean patients on a 16-cm wide-detector CT using 70 kVp and ASiR-V algorithm, in comparison with the conventional 100-kVp protocol. Eur Radiol 2018; 29:3036-3043. [PMID: 30506217 DOI: 10.1007/s00330-018-5837-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 09/28/2018] [Accepted: 10/17/2018] [Indexed: 01/17/2023]
Abstract
OBJECTIVE To investigate the value of prospectively ECG-triggered coronary CT angiography (CCTA) for lean patients with body mass index (BMI) ≤ 23 kg/m2 using 70 kVp and high-level volume-based adaptive statistical iterative reconstruction (ASiR-V) algorithm on a 16-cm wide-detector CT system for reducing both radiation and contrast doses in comparison with the conventional 100-kVp protocol. MATERIALS AND METHODS Thirty patients (group A) were prospectively enrolled to undergo 70-kVp CCTA on a 16-cm wide-detector CT scanner with noise index (NI) of 36 HU and at weight-dependent contrast dose rate of 16 mg I/kg/s for 9-s injection. Images were reconstructed with 80% ASiR-V. Radiation dose, contrast dose, and image quality were statistically compared with 30 patients (group B) in database with matching BMI who underwent conventional 100-kVp CCTA with NI of 25 HU, and at 25 mg I/kg/s rate for 10-s injection and reconstructed with 60% ASiR-V. RESULTS There was no significant difference in patient demographics between the two groups (all p > 0.05). The two groups also had similar mean CT values and contrast-noise ratio (CNR) and subjective image quality (all p > 0.05). However, group A with 70 kVp reduced the effective dose by 75.3% compared with group B (0.43 ± 0.20 mSv vs. 1.74 ± 1.01 mSv, p < 0.001), and required 42.4% less contrast dose than group B (22.46 ± 2.94 ml vs. 38.99 ± 5.10 ml, p < 0.001). CONCLUSIONS Prospectively ECG-triggered CCTA using 70 kVp and high-level ASiR-V on a 16-cm wide-detector CT system provides diagnostic images with substantial reduction in both radiation and contrast doses for patients with BMI ≤ 23 kg/m2 compared to the conventional 100-kVp protocol. KEY POINTS • 70-kVp CCTA produces excellent images at sub-millisievert radiation. • 70-kVp CCTA reduces both radiation and contrast doses over conventional protocol. • Achieving low-dose CCTA with combined low kVp and high-level ASIR-V.
Collapse
Affiliation(s)
- Yuhuan Chen
- Shaanxi University of Chinese Medicine, Xianyang, 712000, China
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, China
| | - Zhentang Liu
- Department of Radiology, Chang'an Hospital, Xi'an, 710018, Shaanxi, China
| | | | - Yong Yu
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, China
| | - Yongjun Jia
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, China
| | - Guangming Ma
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, China
| | - Zhijun Hu
- Department of Radiology, Chang'an Hospital, Xi'an, 710018, Shaanxi, China
| | - DongHong Wei
- Department of Radiology, Chang'an Hospital, Xi'an, 710018, Shaanxi, China
| | - Dou Li
- Department of Radiology, Chang'an Hospital, Xi'an, 710018, Shaanxi, China
| | - Taiping He
- Shaanxi University of Chinese Medicine, Xianyang, 712000, China.
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, China.
| |
Collapse
|