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Nishiyama Y, Yabuuchi K, Nishiyama Y, Kambara Y, Ikushima Y, Enishi T. Crossed raised arm position improves the flow of contrast medium in torso contrast-enhanced computed Tomography. Radiography (Lond) 2024; 30:681-687. [PMID: 38364708 DOI: 10.1016/j.radi.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/18/2024]
Abstract
INTRODUCTION This retrospective cohort study examined the effects of the crossed raised arm (CRA) position in contrast-enhanced computed tomography (CECT) on contrast medium influx and image quality relative to the conventional position. METHODS Contrast medium influx into the collateral veins on CECT images was evaluated in 92 participants. The CT values of the pulmonary artery, descending aorta, and spleen were obtained in both positions and compared. Anatomical changes in the diameters and area of the subclavian vein and costoclavicular distance were also analyzed. RESULTS Contras 27 and 6 patients in the conventional and CRA positions, respectively. The influx risk ratio in the CRA position versus that in the conventional position was 0.22 (95% confidence interval, 0.10-0.51). Elevations in the median CT value of the pulmonary artery, descending aorta, and spleen in the CRA position were 7.0% (p < .001), 7.4% (p < .001), and 9.8% (p < .001), respectively. Enlargements in the major and minor diameters of the subclavian vein, subclavian vein area, and costoclavicular distance in the CRA position versus those in the conventional position were 19.3% (p < .001), 28.1% (p < .001), 53.6%, and 30.0% (p < .001), respectively. CONCLUSION The CRA position effectively prevented contrast medium influx into the collateral veins due to SVS and increased CT values in the target organs in CECT. The diameters and area of the subclavian vein and costoclavicular distance were enlarged at the thoracic outlet, which improved the flow of the contrast medium into the targeted organs. IMPLICATIONS FOR PRACTICE The CRA position can contribute to obtaining better CECT images during common clinical assessments at no additional cost.
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Affiliation(s)
- Y Nishiyama
- Department of Radiology, Tokushima Municipal Hospital 2-34 Kitajosanjima, Tokushima 7700812, Japan.
| | - K Yabuuchi
- Department of Radiology, Tokushima Municipal Hospital 2-34 Kitajosanjima, Tokushima 7700812, Japan.
| | - Y Nishiyama
- Graduate School of Biomedical Sciences, Tokushima University 3-18-15 Kuramoto, Tokushima 7708503, Japan.
| | - Y Kambara
- Department of Radiology, Tokushima Municipal Hospital 2-34 Kitajosanjima, Tokushima 7700812, Japan.
| | - Y Ikushima
- Department of Radiology, Tokushima Municipal Hospital 2-34 Kitajosanjima, Tokushima 7700812, Japan.
| | - T Enishi
- Department of Rehabilitation Medicine, Tokushima Municipal Hospital 2-34 Kitajosanjima, Tokushima 7700812, Japan.
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Gupta D, Roy I, Gandhi S. Metallic nanoparticles for CT-guided imaging of tumors and their therapeutic applications. OPENNANO 2023. [DOI: 10.1016/j.onano.2023.100146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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Noda Y, Takai Y, Asano M, Yamada N, Seko T, Kawai N, Kaga T, Miyoshi T, Hyodo F, Kato H, Matsuo M. Comparison of image quality and pancreatic ductal adenocarcinoma conspicuity between the low-kVp and dual-energy CT reconstructed with deep-learning image reconstruction algorithm. Eur J Radiol 2023; 159:110685. [PMID: 36603479 DOI: 10.1016/j.ejrad.2022.110685] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 12/28/2022] [Indexed: 01/01/2023]
Abstract
PURPOSE To compare the image quality and conspicuity of pancreatic ductal adenocarcinoma (PDAC) between the low-kVp and dual-energy pancreatic protocol CT reconstructed with deep-learning image reconstruction (DLIR). METHOD A cohort of 111 consecutive patients (median age, 72 years; 56 men) undergoing a pancreatic protocol CT were retrospectively analyzed. Among them, 58 patients underwent 80-kVp CT (80-kVp group), and 53 patients underwent dual-energy CT and reconstructed at 40-keV (40-keV group). The medium-strength level of DLIR were used in both groups. Quantitative measurements, qualitative image quality, PDAC conspicuity, and dose-length product (DLP) were compared between the two groups using Mann-Whitney U test. RESULTS A total of 20 and 16 PDACs were found in the 80-kVp and 40-keV groups, respectively. CT numbers of the vasculatures and parenchymal organs (P <.001 for all) and the background noise at both pancreatic and portal venous phases (P <.001) were higher in the 40-keV group than in the 80-kVp group. The signal-to-noise ratio (SNR) of all anatomical structures (P <.001-0.005), except for the liver in reviewer 2 (P =.47), and the tumor-to-pancreas contrast-to-noise ratio (CNR; P <.001-0.01) were higher in the 40-keV group than in the 80-kVp group. No difference was found in the image quality at both phases (P =.30-0.90). PDAC conspicuity was better in the 40-keV group than in the 80-kVp group (P =.007-0.03). DLP at pancreatic (275 vs. 313 mGy*cm; P =.05) and portal venous phases (743 vs. 766 mGy*cm; P =.20) was comparable between the two groups. CONCLUSION Under the same DLP, virtual monoenergetic images at 40-keV demonstrated higher SNR and tumor-to-pancreas CNR and better PDAC conspicuity compared to the 80-kVp setting.
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Affiliation(s)
- Yoshifumi Noda
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan.
| | - Yukiko Takai
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Masashi Asano
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Nao Yamada
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Takuya Seko
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Nobuyuki Kawai
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Tetsuro Kaga
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Toshiharu Miyoshi
- Department of Radiology Services, Gifu University Hospital, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Fuminori Hyodo
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan; Institute for Advanced Study, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Hiroki Kato
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
| | - Masayuki Matsuo
- Department of Radiology, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan
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Delly, Widyastuti W, Aryadi, Hidayat A. Differences in apical vapor lock formation after sodium hypochlorite irrigation with and without surfactant using two needle types. SCIENTIFIC DENTAL JOURNAL 2020. [DOI: 10.4103/sdj.sdj_51_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Ma G, YU Y, Duan H, Dou Y, Jia Y, Zhang X, Yang C, Chen X, Han D, Guo C, He T. Subtraction CT angiography in head and neck with low radiation and contrast dose dual-energy spectral CT using rapid kV-switching technique. Br J Radiol 2018; 91:20170631. [PMID: 29412008 PMCID: PMC6223275 DOI: 10.1259/bjr.20170631] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 01/15/2018] [Accepted: 02/01/2018] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To investigate the application of low radiation and contrast dose spectral CT angiology using rapid kV-switching technique in the head and neck with subtraction method for bone removal. METHODS This prospective study was approved by the local ethics committee. 64 cases for head and neck CT angiology were randomly divided into Groups A (n = 32) and B (n = 32). Group A underwent unenhanced CT with 100 kVp, 200 mA and contrast-enhanced CT with spectral CT mode with body mass index-dependent low dose protocols. Group B used conventional helical scanning with 120 kVp, auto mA for noise index of 12 HU (Hounsfield unit) for both the unenhanced and contrast-enhanced CT. Subtraction images were formed by subtracting the unenhanced images from enhanced images (with the 65 keV-enhanced spectral CT image in Group A). CT numbers and their standard deviations in aortic arch, carotid arteries, middle cerebral artery and air were measured in the subtraction images. The signal-to-noise ratio and contrast-to-noise ratio for the common and internal carotid arteries and middle cerebral artery were calculated. Image quality in terms of bone removal effect was evaluated by two experienced radiologists independently and blindly using a 4-point system. Radiation dose and total iodine load were recorded. Measurements were statistically compared between the two groups. RESULTS The two groups had same demographic results. There was no difference in the CT number, signal-to-noise and contrast-to-noise ratio values for carotid arteries and middle cerebral artery in the subtraction images between the two groups (p > 0.05). However, the bone removal effect score [median (min-max)] in Group A [4 (3-4)] was rated better than in Group B [3 (2-4)] (p < 0.001), with excellent agreement between the two observers (κ > 0.80). The radiation dose in Group A (average of 2.64 mSv) was 57% lower than the 6.18 mSv in Group B (p < 0.001). The total iodine intake in Group A was 13.5g, 36% lower than the 21g in Group B. CONCLUSION Spectral CT imaging with rapid kV-switching in the subtraction angiography in head and neck provides better bone removal with significantly reduced radiation and contrast dose compared with conventional subtraction method. Advances in knowledge: This novel method provides better bone removal with significant radiation and contrast dose reduction compared with the conventional subtraction CT, and maybe used clinically to protect the thyroid gland and ocular lenses from unnecessary high radiation.
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Affiliation(s)
- Guangming Ma
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yong YU
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Haifeng Duan
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yuequn Dou
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yongjun Jia
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Xirong Zhang
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Chuangbo Yang
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Xiaoxia Chen
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Dong Han
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Changyi Guo
- Department of Diagnostic Radiology, The Second Affiliated Hospital of the Shannxi University of Traditional Chinese Medicine, Xianyang, China
| | - Taiping He
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
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Hoshika M, Yasui K, Niguma T, Kojima T, Nishiyama N, Suzuki D, Togami I. Novel contrast-injection protocol for high-resolution abdominal CT-angiography: vascular visualization improvement with vasodilator. Abdom Radiol (NY) 2017; 42:2571-2578. [PMID: 28488179 DOI: 10.1007/s00261-017-1163-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE To evaluate the usefulness of a novel contrast-injection protocol for high-resolution abdominal computed tomography angiography (CTA) using nitroglycerin (NTG). METHODS Abdominal CTA was performed in 80 patients using two 64-detector-row CT scanners. Forty patients were examined after administration of sublingual NTG (NTG group), while 40 were examined without NTG administration (non-NTG group). Arterial phase images were acquired with maximum intensity projection and volume rendering. Reduction rates: vessel cross-sectional areas ratio of 10 cm distal to origin at the superior mesenteric artery, contrast enhancements, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were assessed. Three reviewers evaluated degree of depiction of the peripancreatic vasculature using a four-point scale (1 = poor, 4 = excellent). RESULTS Reduction rates were significantly lower in the NTG group (P < 0.001), while there were no significant differences in contrast enhancements, SNR, or CNR between groups. Visual evaluation results of the NTG group were significantly better than those of the non-NTG group (P < 0.01). CONCLUSION Abdominal CTA using NTG improved visualization of the abdominal peripheral vessels. This improved arterial view may be beneficial for preoperative evaluation of the arterial anatomy.
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Affiliation(s)
- Minori Hoshika
- Department of Radiology (Services), Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-Shi, Okayama, 700-8511, Japan.
| | - Kotaro Yasui
- Department of Radiology, Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-shi, Okayama, 700-8511, Japan
| | - Takefumi Niguma
- Department of Surgery, Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-shi, Okayama, 700-8511, Japan
| | - Toru Kojima
- Department of Surgery, Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-shi, Okayama, 700-8511, Japan
| | - Norimi Nishiyama
- Department of Radiology (Services), Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-Shi, Okayama, 700-8511, Japan
| | - Daisuke Suzuki
- Department of Radiology (Services), Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-Shi, Okayama, 700-8511, Japan
| | - Izumi Togami
- Department of Radiology, Okayama Saiseikai General Hospital, 2-25 Kokutai-cho, Kita-ku, Okayama-shi, Okayama, 700-8511, Japan
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Zhu F, Wu W, Zhu F, Wang Y, Wang Y, Xia T. Influence of computed tomography contrast agent on radiotherapy dose calculation for pancreatic carcinoma: A dosimetric study based on tomotherapy and volumetric-modulated arc therapy techniques. Med Dosim 2017; 42:317-325. [PMID: 28818321 DOI: 10.1016/j.meddos.2017.07.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 04/18/2017] [Accepted: 07/03/2017] [Indexed: 11/30/2022]
Abstract
The main purpose of our investigation was to quantify the dosimetric influence of intravenous contrast agent for pancreatic cancer radiotherapy treatment. This study focused on complex modulated irradiation techniques of tomotherapy (TOMO) and volumetric-modulated arc therapy (VMAT) to investigate if novel conformal treatment methods could reduce the influence of contrast agent. In our study, patients with pancreatic cancer were enrolled to have 2 computed tomography (CT) scans in the same position without and with intravenous contrast agent for treatment planning. Then tumors and organ at risks were countered on contrast-enhanced CT (CECT) images. Each patient's CECT was assigned a TOMO plan and a VMAT plan. Then these plans were copied onto the non-CECT image and dose distribution was calculated with the same algorithm and structure sets. Finally, the dose distribution and the dose difference were analyzed for the target volume and organs at risk between the 2 sets of images. The statistic dosimetric result showed that for both TOMO and VMAT, no significant dose difference between CECT and non-CECT-based plan was observed. Dose difference was clinically negligible because the average relative percentage dose difference was 1% ± 1% for target volume, except a blurring effect at the higher dose region of the target volume. It implied that intravenous contrast agent will not affect dose calculation for pancreatic cancer radiotherapy significantly. Also the dose deviation based on TOMO showed no statistical difference compared with that on VMAT. For both superposition/conversation algorithm used by TOMO and Monte Carlo algorithm used by VMAT, the dosimetric difference was nonsignificant. A full analysis demonstrated a negligible dose difference of less than 1% between CECT-based plan and non-CECT-based plan. Therefore, contrast-enhanced CT image can be used directly for dose calculation of TOMO and VMAT plans for pancreatic cancer. It is unnecessary to scan twice then make a fusion of CECT and non-CECT, which would result to additional unnecessary radiation dose to patient and decrease work efficiency.
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Affiliation(s)
- Feng Zhu
- Department of Radiation Oncology, PLA General Airforce Hospital, 30 Fucheng Street, Beijing 100142, China
| | - Weizhang Wu
- Department of Radiation Oncology, PLA General Airforce Hospital, 30 Fucheng Street, Beijing 100142, China
| | - Fuhai Zhu
- Department of Radiation Oncology, PLA General Airforce Hospital, 30 Fucheng Street, Beijing 100142, China
| | - Yong Wang
- Department of Radiation Oncology, PLA General Airforce Hospital, 30 Fucheng Street, Beijing 100142, China
| | - Yingjie Wang
- Department of Radiation Oncology, PLA General Airforce Hospital, 30 Fucheng Street, Beijing 100142, China
| | - Tingyi Xia
- Department of Radiation Oncology, PLA General Airforce Hospital, 30 Fucheng Street, Beijing 100142, China.
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Aschoff AJ, Catalano C, Kirchin MA, Krix M, Albrecht T. Low radiation dose in computed tomography: the role of iodine. Br J Radiol 2017; 90:20170079. [PMID: 28471242 PMCID: PMC5603952 DOI: 10.1259/bjr.20170079] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Recent approaches to reducing radiation exposure during CT examinations typically utilize automated dose modulation strategies on the basis of lower tube voltage combined with iterative reconstruction and other dose-saving techniques. Less clearly appreciated is the potentially substantial role that iodinated contrast media (CM) can play in low-radiation-dose CT examinations. Herein we discuss the role of iodinated CM in low-radiation-dose examinations and describe approaches for the optimization of CM administration protocols to further reduce radiation dose and/or CM dose while maintaining image quality for accurate diagnosis. Similar to the higher iodine attenuation obtained at low-tube-voltage settings, high-iodine-signal protocols may permit radiation dose reduction by permitting a lowering of mAs while maintaining the signal-to-noise ratio. This is particularly feasible in first pass examinations where high iodine signal can be achieved by injecting iodine more rapidly. The combination of low kV and IR can also be used to reduce the iodine dose. Here, in optimum contrast injection protocols, the volume of CM administered rather than the iodine concentration should be reduced, since with high-iodine-concentration CM further reductions of iodine dose are achievable for modern first pass examinations. Moreover, higher concentrations of CM more readily allow reductions of both flow rate and volume, thereby improving the tolerability of contrast administration.
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Affiliation(s)
- Andrik J Aschoff
- 1 Department for Diagnostic and Interventional Radiology and Neuroradiology, Klinikum Kempten, Kempten, Germany
| | - Carlo Catalano
- 2 Department of Radiological Sciences, University of Rome "La Sapienza", Rome, Italy
| | - Miles A Kirchin
- 3 Bracco Imaging SpA, Global Medical & Regulatory Affairs, Milan, Italy
| | - Martin Krix
- 4 Bracco Imaging Germany, Global Medical & Regulatory Affairs, Konstanz, Germany
| | - Thomas Albrecht
- 5 Institut für Radiologie und Interventionelle Therapie, Vivantes-Klinikum Neukölln, Berlin, Germany
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Granata V, Fusco R, Catalano O, Setola SV, de Lutio di Castelguidone E, Piccirillo M, Palaia R, Grassi R, Granata F, Izzo F, Petrillo A. Multidetector computer tomography in the pancreatic adenocarcinoma assessment: an update. Infect Agent Cancer 2016; 11:57. [PMID: 27891175 PMCID: PMC5111267 DOI: 10.1186/s13027-016-0105-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/03/2016] [Indexed: 02/07/2023] Open
Abstract
Ductal adenocarcinoma of the pancreas is one of the most aggressive forms of cancer, with only a minority of cases being resectable at the moment of their diagnosis. The accurate detection and characterization of pancreatic carcinoma is very important for patient management. Multidetector-row computed tomography (MDCT) has become the cross-sectional modality of choice in the diagnosis, staging, treatment planning, and follow-up of patients with pancreatic tumors. However, approximately 11% of ductal adenocarcinomas still remain undetected at MDCT because of the lack of attenuation gradient between the lesion and the adjacent pancreatic parenchyma. In this systematic literature review we investigate the current evolution of the CT technique, limitations, and perspectives in the evaluation of pancreatic carcinoma.
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Affiliation(s)
- Vincenza Granata
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Roberta Fusco
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Orlando Catalano
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Sergio Venanzio Setola
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | | | - Mauro Piccirillo
- Department of Hepato-Biliary Surgery, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Raffaele Palaia
- Department of Hepato-Biliary Surgery, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Roberto Grassi
- Departement of Radiology, Seconda Università degli Studi di Napoli, Naples, Italy
| | - Francesco Granata
- Departement of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Lazio, Italy
| | - Francesco Izzo
- Department of Hepato-Biliary Surgery, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
| | - Antonella Petrillo
- Department of Diagnostic Imaging, radiant and metabolic Therapy, Istituto Nazionale Tumori IRCCS Fondazione Pascale, Naples, Italy
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Wang X, Zhong Y, Hu L, Xue L, Shi M, Qiu H, Li J. A prospective evaluation of the contrast, radiation dose and image quality of contrast-enhanced CT scans of paediatric abdomens using a low-concentration iodinated contrast agent and low tube voltage combined with 70% ASIR algorithm. Int J Clin Pract 2016; 70 Suppl 9B:B16-21. [PMID: 27577509 DOI: 10.1111/ijcp.12853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 06/15/2016] [Indexed: 10/21/2022] Open
Abstract
PURPOSE To quantitatively and subjectively assess the image quality of and radiation dose for an abdominal enhanced computed tomography (CT) scan with a low tube voltage and a low concentration of iodinated contrast agent in children. METHODS Forty-eight patients were randomised to one of the two following protocols: Group A (n=24, mean age 46.96±44.65 months, mean weight 15.71±9.11 kg, BMI 16.48±2.40 kg/m(2) ) and Group B (n=24, mean age 41.33±44.59 months, mean weight 18.15±17.67 kg, BMI 17.50±3.73 kg/m(2) ). Group A: 80 kVp tube voltage, 270 mg iodine (I)/mL contrast agent (Visipaque, GE Healthcare) and images were reconstructed using 70% adaptive statistical iterative reconstruction (ASIR). Group B: 100 kVp tube voltage, 370 mg I/mL contrast agent (Iopamiro, Bracco) and images were reconstructed using 50% ASIR. The volume of the contrast agent was 1.30 mL/kg in both Groups A and B. The degree of enhancement and noise in the abdominal aorta (AO) in the arterial phase (AP) and the portal vein (PV) in the portal venous phase (PVP) was measured; while the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) for the AO and PV were calculated. A 5-point scale was used to subjectively evaluate the image quality and image noise by two radiologists with more than 10 years of experience. Dose-length product (DLP) (mGy-cm) and CTDIvol (mGy) were calculated. Objective measurements and subjective quality scores for the two groups were compared using paired t-tests and Mann-Whitney U tests, respectively. RESULTS There was no significant difference in age, weight or body mass index (BMI) between the two groups (all P>.5). The iodine load in Group A (5517.3±3197.2 mg I) was 37% lower than that in Group B (8772.1±8474.6 mg I), although there was no significant difference between them (P=.111). The DLP and the CT dose index (CTDIvol ) for Group A were also lower than for Group B, but were not statistically significantly different (DLP, 104 mGy-cm±45.81 vs 224.5 mGy-cm±45.83; CTDIvol, 1.44 mGy±0.50 vs 2.08 mGy±1.87, all P>.05). The mean arterial and portal venous enhancement (255.33 HU±83.42, 146.41 HU±23.45, respectively), noise (AP 14.96 HU±2.09, PVP 16.30 HU±3.21), CNRs (AO 14.54±7.12, PV 5.07±1.73) and SNRs (AO 20.76±6.76, PV 12.43±3.24) for Group A were similar to Group B (enhancement: 226.55 HU±77.71, 138.69 HU±33.22; noise: 14.92 HU±3.12, 15.36 HU±3.48; CNRs: 12.96±7.14, 5.16±2.28; SNRs: 19.13±7.30, 12.69±4.22; all P>.05). The mean scores of the quality of the AP and PVP images in Group B were 4.31±0.53 and 4.35±0.52, respectively, while the scores obtained in Group A were 4.29±0.51 and 4.25±0.51; there were no statistically significant differences between the two groups. CONCLUSION The scanning protocol using a low tube voltage (80 kVp) together with 70% ASIR and a low-concentration iodinated contrast agent (270 mg I/mL) enables a 37% reduction in iodine load and a 30% reduction in radiation dose while maintaining compatible image quality.
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Affiliation(s)
- Xiaoxia Wang
- Diagnostic Imaging Center, Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University Medical School, Shanghai, China
| | - Yumin Zhong
- Diagnostic Imaging Center, Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University Medical School, Shanghai, China
| | - Liwei Hu
- Diagnostic Imaging Center, Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University Medical School, Shanghai, China
| | - Lianyan Xue
- Diagnostic Imaging Center, Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University Medical School, Shanghai, China
| | - Meihua Shi
- Diagnostic Imaging Center, Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University Medical School, Shanghai, China
| | - Haisheng Qiu
- Diagnostic Imaging Center, Shanghai Children's Medical Center affiliated with Shanghai Jiao Tong University Medical School, Shanghai, China
| | - Jianying Li
- CT Research Center, GE Healthcare China, Shanghai, China
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Xin L, Yang X, Huang N, Du X, Zhang J, Wang Y, Hou L, Gao J. The initial experience of the upper abdominal CT angiography using low-concentration contrast medium on dual energy spectral CT. ACTA ACUST UNITED AC 2015; 40:2894-9. [DOI: 10.1007/s00261-015-0462-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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He W, Huda W, Mah E, Yao H. Does administering iodine in radiological procedures increase patient doses? Med Phys 2014; 41:113901. [PMID: 25370675 DOI: 10.1118/1.4898594] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The authors investigated the changes in the pattern of energy deposition in tissue equivalent phantoms following the introduction of iodinated contrast media. METHODS The phantom consisted of a small "contrast sphere," filled with water or iodinated contrast, located at the center of a 28 cm diameter water sphere. Monte Carlo simulations were performed using mcnp5 codes, validated by simulating irradiations with analytical solutions. Monoenergetic x-rays ranging from 35 to 150 keV were used to simulate exposures to spheres containing contrast agent with iodine concentrations ranging from 1 to 100 mg/ml. Relative values of energy imparted to the contrast sphere, as well as to the whole phantom, were calculated. Changes in patterns of energy deposition around the contrast sphere were also investigated. RESULTS Small contrast spheres can increase local absorbed dose by a factor of 13, but the corresponding increase in total energy absorbed was negligible (<1%). The highest localized dose increases were found to occur at incident photon energies of about 60 keV. For a concentration of about 10 mg/ml, typical of clinical practice, localized absorbed doses were generally increased by about a factor of two. At this concentration of 10 mg/ml, the maximum increase in total energy deposition in the phantom was only 6%. These simulations demonstrated that increases in contrast sphere doses were offset by corresponding dose reductions at distal and posterior locations. CONCLUSIONS Adding iodine can result in values of localized absorbed dose increasing by more than an order of magnitude, but the total energy deposition is generally very modest (i.e., <10%). Their data show that adding iodine primarily changes the pattern of energy deposition in the irradiated region, rather than increasing patient doses per se.
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Affiliation(s)
- Wenjun He
- Clemson-MUSC Bioengineering Program, Department of Bioengineering, Clemson University, Charleston, South Carolina 29425
| | - Walter Huda
- Department of Radiology and Radiological Science, Medical University of South Carolina (MUSC), Charleston, South Carolina 29425
| | - Eugene Mah
- Department of Radiology and Radiological Science, Medical University of South Carolina (MUSC), Charleston, South Carolina 29425
| | - Hai Yao
- Clemson-MUSC Bioengineering Program, Department of Bioengineering, Clemson University, Charleston, South Carolina 29425
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Sakane M, Kim T, Hori M, Onishi H, Nakamoto A, Tsuboyama T, Tatsumi M, Tomiyama N. Effects of High-concentration contrast material and low-voltage CT on contrast for multiphasic CT of the upper abdomen: comparison using the simulation with virtual monochromatic imaging obtained by fast-switch kVp dual-energy CT. SPRINGERPLUS 2014; 3:234. [PMID: 24891998 PMCID: PMC4039664 DOI: 10.1186/2193-1801-3-234] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 04/17/2014] [Indexed: 02/06/2023]
Abstract
Objective The purpose of this study was to compare the effects of high-concentration contrast material and low-voltage CT simulated by virtual monochromatic (VM) imaging on contrast enhancement at multiphasic CT of the upper abdomen. Methods This study included 72 patients who underwent CT during early arterial (EAP), late arterial and portal venous phases after 300-mgI/ml (Group A; 34 patients) or 350-mg/ml (Group B; 38 patients) contrast-material injection at the same volumetric rate (0.067 mL/sec/kg). VM images were generated at 50 and 65 keV. Contrast-to-noise ratios (CNRs) of aorta, portal vein, and liver parenchyma were calculated and statistically compared. Results Mean CNRs for 50-keV VM images were significantly higher than 65-keV VM images of each organ at any phases (p < 0.05), except for hepatic parenchyma in EAP. Aortic CNRs in EAP on 65- and 50-keV images of Group B were significantly higher than Group A (p <0.05, respectively). Aortic CNR on 50-keV images of Group A and on 65-keV images of Group B were 11% and 21% higher than 65-keV images of Group A, respectively. Conclusions Low-voltage CT simulated by VM image improved contrast enhancement through any phases, while high-concentration contrast material increased only arterial contrast in EAP more effectively.
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Affiliation(s)
- Makoto Sakane
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Tonsok Kim
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Masatoshi Hori
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Hiromitsu Onishi
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Atsushi Nakamoto
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Takahiro Tsuboyama
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Mitsuaki Tatsumi
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Noriyuki Tomiyama
- Department of Radiology, Osaka University Graduate School of Medicine, D1, 2-2, Yamadaoka, Suita, Osaka, 565-0871 Japan
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CT angiography of the head-and-neck vessels acquired with low tube voltage, low iodine, and iterative image reconstruction: clinical evaluation of radiation dose and image quality. PLoS One 2013; 8:e81486. [PMID: 24339936 PMCID: PMC3855260 DOI: 10.1371/journal.pone.0081486] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/21/2013] [Indexed: 02/06/2023] Open
Abstract
Objectives We aimed to assess the effectiveness and feasibility of head-and-neck Computed Tomography Angiography (CTA) with low tube voltage and low concentration contrast media combined with iterative reconstruction algorithm. Methods 92 patients were randomly divided into group A and B: patients in group A received a conventional scan with 120 kVp and contrast media of 320 mgI/ml. Patients in group B, 80 kVp and contrast media of 270 mgI/ml were used along with iterative reconstruction algorithm techniques. Image quality, radiation dose and the effectively consumed iodine amount between two groups were analyzed and compared. Results Image quality of CTA of head-and-neck vessels obtained from patients in group B was significantly improved quantitatively and qualitatively. In addition, CT attenuation values in group B were also significantly higher than that in group A (p<0.001). Furthermore, compared with the protocol whereby 120 kVp and 320 mgI/dl were administrated, the mean radiation dose and consumed iodine amount in protocol B were also reduced by 50% and 15.6%, respectively (p<0.001). Conclusions With the help of iterative reconstruction algorithm techniques, the head-and-neck CTA with diagnostic quality can be adequately acquired with low tube voltage and low concentration contrast media. This method could be potentially extended to include any part of the body to reduce the risks related to ionizing radiation.
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SHERIDAN MB, MANOHARAN P. Neoplasms of the pancreas. IMAGING 2013. [DOI: 10.1259/imaging/20369618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ramgren B, Björkman-Burtscher IM, Holtås S, Siemund R. CT angiography of intracranial arterial vessels: impact of tube voltage and contrast media concentration on image quality. Acta Radiol 2012; 53:929-34. [PMID: 22903017 DOI: 10.1258/ar.2012.120218] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Computed tomography angiography (CTA) of intracranial arteries has high demands on image quality. Important parameters influencing vessel enhancement are injection rate, concentration of contrast media and tube voltage. PURPOSE To evaluate the impact of an increase of contrast media concentration from 300 to 400 mg iodine/mL (mgI/mL) and the effect of a decrease of tube voltage from 120 to 90 kVp on vessel attenuation and image quality in CT angiography of intracranial arteries. MATERIAL AND METHODS Sixty-three patients were included into three protocol groups: Group I, 300 mgI/mL 120 kVp; Group II, 400 mgI/mL 120 kVp; Group III, 400 mgI/mL 90 kVp. Hounsfield units (HU) were measured in the internal carotid artery (ICA) and the M1 and M2 segments of the middle cerebral artery. Image quality grading was performed regarding M1 and M2 segments, volume rendering and general image impression. RESULTS The difference in mean HU in ICA concerning the effect of contrast media concentration was statistically significant (P = 0.03) in favor of higher concentration. The difference in ICA enhancement due to the effect of tube voltage was statistically significant (P < 0.01) in favor of lower tube voltage. The increase of contrast medium concentration raised the mean enhancement in ICA with 18% and the decrease of tube voltage raised the mean enhancement with 37%. Image quality grading showed a trend towards improved grading for higher contrast concentration and lower tube voltage. Statistically significant better grading was found for the combined effect of both measures except for general impression (P 0.01-0.05). CONCLUSION The uses of highly concentrated contrast media and low tube voltage are easily performed measures to improve image quality in CTA of intracranial vessel.
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Affiliation(s)
- Birgitta Ramgren
- Center for Medical Imaging and Physiology, Skåne University Hospital, Lund
- Department of Radiology, Lund University, Lund
| | - Isabella M Björkman-Burtscher
- Center for Medical Imaging and Physiology, Skåne University Hospital, Lund
- Department of Radiology, Lund University, Lund
- Lund University Bioimaging Center, Lund University, Lund, Sweden
| | - Stig Holtås
- Center for Medical Imaging and Physiology, Skåne University Hospital, Lund
- Department of Radiology, Lund University, Lund
| | - Roger Siemund
- Center for Medical Imaging and Physiology, Skåne University Hospital, Lund
- Department of Radiology, Lund University, Lund
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Stuber T, Brambs HJ, Freund W, Juchems MS. Sixty-four MDCT achieves higher contrast in pancreas with optimization of scan time delay. World J Radiol 2012; 4:324-7. [PMID: 22900134 PMCID: PMC3419869 DOI: 10.4329/wjr.v4.i7.324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 06/16/2012] [Accepted: 06/23/2012] [Indexed: 02/06/2023] Open
Abstract
AIM: To compare different multidetector computed tomography (MDCT) protocols to optimize pancreatic contrast enhancement.
METHODS: Forty consecutive patients underwent contrast-enhanced biphasic MDCT (arterial and portal-venous phase) using a 64-slice MDCT. In 20 patients, the scan protocol was adapted from a previously used 40-channel MDCT scanner with arterial phase scanning initiated 11.1 s after a threshold of 150 HU was reached in the descending aorta, using automatic bolus tracking (Protocol 1). The 11.1-s delay was changed to 15 s in the other 20 patients to reflect the shorter scanning times on the 64-channel MDCT compared to the previous 40-channel system (Protocol 2). HU values were measured in the head and tail of the pancreas in the arterial and portal-venous phase.
RESULTS: Using an 11.1-s delay, 74.2 HU (head) were measured on average in the arterial phase and 111.2 HU (head) were measured using a 15-s delay (P < 0.0001). For the pancreatic tail, the average attenuation level was 76.73 HU (11.1 s) and 99.89 HU (15 s) respectively (P = 0.0002). HU values were also significantly higher in the portal-venous phase [pancreatic head: 70.5 HU (11.1 s) vs 84.0 HU (15 s) (P = 0.0014); pancreatic tail: 67.45 HU (11.1 s) and 77.18 HU (15 s) using Protocol 2 (P = 0.0071)].
CONCLUSION: Sixty-four MDCT may yield a higher contrast in pancreatic study with (appropriate) optimization of scan delay time.
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Jung SC, Cho JY, Kim SH. Subtype differentiation of small renal cell carcinomas on three-phase MDCT: usefulness of the measurement of degree and heterogeneity of enhancement. Acta Radiol 2012; 53:112-8. [PMID: 22114020 DOI: 10.1258/ar.2011.110221] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Subtype differentiation of small renal cell carcinomas (RCCs) can provide more information to surgeons and patients and get more useful information about imaging features of small renal tumors. PURPOSE To evaluate the usefulness of the measurement of degree and heterogeneity of enhancement in subtype differentiation of small renal cell carcinomas (RCCs) by three-phase multidetector-row CT (MDCT). MATERIAL AND METHODS We reviewed 149 pathologically confirmed small (<4cm) RCCs in 143 patients: 114 (clear cell), 17 (chromophobe), and 18 papillary (8 papillary type 1 and 10 papillary type 2). Scans in pre-contrast, corticomedullary, and nephrographic phases were obtained. We assessed the mean and standard deviation of the Hounsfield units (HU) in a region of interest (ROI) for the degree of enhancement and the heterogeneity of enhancement, respectively. We compared the attenuation values, and the degree and heterogeneity of enhancement among the subtypes. RESULTS The clear cell type showed the highest enhancement and heterogeneity of enhancement followed by chromophobe and papillary types. There was a significant difference in enhancement between the clear cell and papillary types in the corticomedullary phase (P < 0.01), and between clear and non-clear cell types in the nephrographic phase (P < 0.05). Heterogeneity of enhancement showed a significant difference between clear cell and non-clear cell types in the corticomedullary phase (P < 0.05). CONCLUSION The measurement of degree and heterogeneity of enhancement on contrast-enhanced MDCT may be a simple and useful method to differentiate between the different types of small RCCs.
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Affiliation(s)
- Seung Chai Jung
- Department of Radiology, Seoul National University College of Medicine, Seoul
- Institute of Radiation Medicine and Kidney Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Jeong Yeon Cho
- Department of Radiology, Seoul National University College of Medicine, Seoul
- Institute of Radiation Medicine and Kidney Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Seung Hyup Kim
- Department of Radiology, Seoul National University College of Medicine, Seoul
- Institute of Radiation Medicine and Kidney Research Institute, Seoul National University Medical Research Center, Seoul, Korea
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Jung SC, Kim SH, Cho JY. A comparison of the use of contrast media with different iodine concentrations for multidetector CT of the kidney. Korean J Radiol 2011; 12:714-21. [PMID: 22043154 PMCID: PMC3194776 DOI: 10.3348/kjr.2011.12.6.714] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 05/06/2011] [Indexed: 12/02/2022] Open
Abstract
Objective To determine the optimal iodine concentration of contrast media for kidney multidetector computed tomography (MDCT) by comparing the degree of renal parenchymal enhancement and the severity of the renal streak artifact with contrast media of different iodine concentrations. Materials and Methods A 16-row MDCT was performed in 15 sedated rabbits by injection of 2 mL contrast media/kg body weight at a rate of 0.3 mL/sec. Monomeric nonionic contrast media of 250, 300, and 370 mg iodine/mL were injected at 1-week intervals. Mean attenuation values were measured in each renal structure with attenuation differences among the structures. The artifact was evaluated by CT window width/level and three grading methods. The values were compared with iodine concentrations. Results The 370 mg iodine/mL concentration showed significantly higher cortical enhancement than 250 mg iodine/mL in all phases (p < 0.05). There was however no significant difference in the degree of enhancement between the 300 mg iodine/mL and 370 mg iodine/mL concentrations in all phases. There is a significant difference in attenuation for the cortex-outer medulla between 250 mg iodine/mL and 300 mg iodine/mL (p < 0.05). The artifact was more severe with a medium of 370 mg iodine/mL than with 250 mg iodine/mL by all grading methods (p < 0.05). Conclusion The 300 mg iodine/mL is considered to be the most appropriate iodine concentration in an aspect of the enhancement and artifact on a kidney MDCT scan.
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Affiliation(s)
- Seung Chai Jung
- Department of Radiology, Seoul National University College of Medicine, Seoul, Korea
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Guerrisi A, Marin D, Nelson RC, De Filippis G, Di Martino M, Barnhart H, Masciangelo R, Guerrisi I, Passariello R, Catalano C. Effect of varying contrast material iodine concentration and injection technique on the conspicuity of hepatocellular carcinoma during 64-section MDCT of patients with cirrhosis. Br J Radiol 2011; 84:698-708. [PMID: 21750137 DOI: 10.1259/bjr/21539234] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVES The aim of this study was to compare the intraindividual effects of contrast material with two different iodine concentrations on the conspicuity of hepatocellular carcinoma (HCC) and vascular and hepatic contrast enhancement during multiphasic, 64-section multidetector row CT (MDCT) in patients with cirrhosis using two contrast medium injection techniques. METHODS Patients were randomly assigned to one of two groups with an equal iodine dose but different contrast material injection techniques: scheme A, fixed injection duration (25 s), and scheme B, fixed injection flow rate (4 ml s(-1)). For each group, patients were randomised to receive both moderate-concentration contrast medium (MCCM) and high-concentration contrast medium (HCCM) during two CT examinations within 3 months. Enhancement of the aorta, liver and portal vein and the tumour-to-liver contrast-to-noise ratio (CNR) were compared between MCCM and HCCM. RESULTS 30 patients (mean age 59 years; range 45-80 years; 16 patients in scheme A and 14 in scheme B) with a total of 31 confirmed HCC nodules were prospectively enrolled. For scheme B, the mean contrast enhancement of the aorta and tumour-to-liver CNR were significantly higher with HCCM than with MCCM during the hepatic arterial phase (+350.5 HU vs +301.1 HU, p = 0.001, and +7.5 HU vs +5.5 HU, p = 0.004). For both groups, there was no significant difference between MCCM and HCCM for all other comparisons. CONCLUSION For a constant injection flow rate, HCCM significantly improves the conspicuity of HCC lesions and aortic enhancement during the hepatic arterial phase on 64-section MDCT in patients with cirrhosis.
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Affiliation(s)
- A Guerrisi
- Department of Radiological Sciences, University of Rome Sapienza, Rome 00159, Italy
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Marin D, Nelson RC, Barnhart H, Schindera ST, Ho LM, Jaffe TA, Yoshizumi TT, Youngblood R, Samei E. Detection of pancreatic tumors, image quality, and radiation dose during the pancreatic parenchymal phase: effect of a low-tube-voltage, high-tube-current CT technique--preliminary results. Radiology 2010; 256:450-9. [PMID: 20656835 DOI: 10.1148/radiol.10091819] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PURPOSE To intraindividually compare a low-tube-voltage (80 kVp), high-tube-current (675 mA) computed tomographic (CT) technique with a high-tube-voltage (140 kVp) CT protocol for the detection of pancreatic tumors, image quality, and radiation dose during the pancreatic parenchymal phase. MATERIALS AND METHODS This prospective, single-center, HIPAA-compliant study was approved by the institutional review board, and written informed consent was obtained. Twenty-seven patients (nine men, 18 women; mean age, 64 years) with 23 solitary pancreatic tumors underwent dual-energy CT. Two imaging protocols were used: 140 kVp and 385 mA (protocol A) and 80 kVp and 675 mA (protocol B). For both protocols, the following variables were compared during the pancreatic parenchymal phase: contrast enhancement for the aorta, the pancreas, and the portal vein; pancreas-to-tumor contrast-to-noise ratio (CNR); noise; and effective dose. Two blinded, independent readers qualitatively scored the two data sets for tumor detection and image quality. Random-effect analysis of variance tests were used to compare differences between the two protocols. RESULTS Compared with protocol A, protocol B yielded significantly higher contrast enhancement for the aorta (508.6 HU vs 221.5 HU, respectively), pancreas (151.2 HU vs 67.0 HU), and portal vein (189.7 HU vs 87.3 HU), along with a greater pancreas-to-tumor CNR (8.1 vs 5.9) (P < .001 for all comparisons). No statistically significant difference in tumor detection was observed between the two protocols. Although standard deviation of image noise increased with protocol B (11.5 HU vs 18.6 HU), this protocol significantly reduced the effective dose (from 18.5 to 5.1 mSv; P < .001). CONCLUSION A low-tube-voltage, high-tube-current CT technique has the potential to improve the enhancement of the pancreas and peripancreatic vasculature, improve tumor conspicuity, and reduce patient radiation dose during the pancreatic parenchymal phase.
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Affiliation(s)
- Daniele Marin
- Department of Radiology, Duke University Medical Center, Erwin Rd, Durham, NC 27710, USA
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Positional reproducibility of pancreatic tumors under end-exhalation breath-hold conditions using a visual feedback technique. Int J Radiat Oncol Biol Phys 2010; 79:1565-71. [PMID: 20832187 DOI: 10.1016/j.ijrobp.2010.05.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 05/24/2010] [Accepted: 05/25/2010] [Indexed: 12/25/2022]
Abstract
PURPOSE To assess positional reproducibility of pancreatic tumors under end-exhalation (EE) breath-hold (BH) conditions with a visual feedback technique based on computed tomography (CT) images. METHODS AND MATERIALS Ten patients with pancreatic cancer were enrolled in an institutional review board-approved trial. All patients were placed in a supine position on an individualized vacuum pillow with both arms raised. At the time of CT scan, they held their breath at EE with the aid of video goggles displaying their abdominal displacement. Each three-consecutive helical CT data set was acquired four times (sessions 1-4; session 1 corresponded to the time of CT simulation). The point of interest within or in proximity to a gross tumor volume was defined based on certain structural features. The positional variations in point of interest and margin size required to cover positional variations were assessed. RESULTS The means ± standard deviations (SDs) of intrafraction positional variations were 0.0 ± 1.1, 0.1 ± 1.2, and 0.1 ± 1.0 mm in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions, respectively (p = 0.726). The means ± SDs of interfraction positional variations were 0.3 ± 2.0, 0.8 ± 1.8, and 0.3 ± 1.8 mm in the LR, AP, and SI directions, respectively (p = 0.533). Population-based margin sizes required to cover 95th percentiles of the overall positional variations were 4.7, 5.3, and 4.9 mm in the LR, AP, and SI directions, respectively. CONCLUSIONS A margin size of 5 mm was needed to cover the 95th percentiles of the overall positional variations under EE-BH conditions, using this noninvasive approach to motion management for pancreatic tumors.
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Sk Md. N, Kim HK, Park JA, Chang YM, Kim TJ. Gold Nanoparticles Coated with Gd-Chelate as a Potential CT/MRI Bimodal Contrast Agent. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.5.1177] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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25
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Liu Y, Xu X, Lin X, Song Q, Chen K. Prospective study comparing two iodine concentrations for multidetector computed tomography of the pancreas. Radiol Med 2010; 115:898-905. [DOI: 10.1007/s11547-010-0544-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 08/06/2009] [Indexed: 02/06/2023]
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Park JA, Kim HK, Kim JH, Jeong SW, Jung JC, Lee GH, Lee J, Chang Y, Kim TJ. Gold nanoparticles functionalized by gadolinium-DTPA conjugate of cysteine as a multimodal bioimaging agent. Bioorg Med Chem Lett 2010; 20:2287-91. [PMID: 20188545 DOI: 10.1016/j.bmcl.2010.02.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Revised: 01/23/2010] [Accepted: 02/01/2010] [Indexed: 01/25/2023]
Abstract
The synthesis and characterization of gold nanoparticles coated with Gd-chelate (Au@GdL), where L is a conjugate of DTPA and cysteine, is described. These particles are obtained by the replacement of citrate from the gold nanoparticle surfaces with gadolinium chelate (GdL). The average size of Au@GdL is 14 nm with a loading of GdL reaching up to 2.9x10(3) per particles, and they demonstrate very high R1 relaxivity (approximately 10(5) mM(-1) s(-1)) as well as X-ray attenuation. The R1 relaxivity per [Gd] is 17.9 mM(-1) s(-1). The present system also exhibits macrophage-specific property, as demonstrated by histological and TEM images as well as CT and MR, rendering itself as a new class of T1 multimodal CT/MR contrast agent.
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Affiliation(s)
- Ji-Ae Park
- Laboratory of Nuclear Medicine Research, Molecular Imaging Center, Korea Institute of Radiological and Medical Science, Seoul, Republic of Korea
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Boraschi P, Donati F, Gigoni R, Salemi S, Faggioni L, Del Chiaro M, Boggi U, Bartolozzi C, Falaschi F. Secretin-stimulated multi-detector CT versus mangafodipir trisodium-enhanced MR imaging plus MRCP in characterization of non-metastatic solid pancreatic lesions. Dig Liver Dis 2009; 41:829-37. [PMID: 19303825 DOI: 10.1016/j.dld.2009.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 01/26/2009] [Accepted: 02/10/2009] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND AIM Our study was aimed to compare multiphasic multi-detector computed tomography after secretin stimulation and mangafodipir trisodium-enhanced magnetic resonance imaging plus MR cholangiopancreatography in the characterization of solid pancreatic lesions. PATIENTS AND METHODS Forty patients with ultrasound diagnosis of solid pancreatic lesion prospectively underwent both multi-detector computed tomography and magnetic resonance imaging. Three minutes after intravenous administration of secretin, post-contrast computed tomography scans were performed 40, 80, and 180 s after contrast medium injection. MR protocol included axial/coronal, thin/thick-slab, single-shot T2 w sequences and axial/coronal T1 w breath-hold spoiled gradient-echo images before and 30-40 min after intravenous infusion of manganese dipyri-doxal diphosphate. Different observers blindly evaluated the ability of computed tomography and magnetic resonance imaging to characterize focal pancreatic lesions. Surgery, biopsy, and/or follow-up were considered as our diagnostic gold standard. RESULTS Thirty-five focal pancreatic lesions (adenocarcinoma, n=18; focal chronic pancreatitis, n=4; endocrine tumor, n=6; metastasis, n=1; cystic tumor, n=3; indeterminate cystic lesions, n=3) were present in 34 patients since the remaining 6 subjects showed no pathological finding. Both multi-detector computed tomography and magnetic resonance imaging showed a statistically significant correlation with the gold standard and between themselves in the characterization of 29 solid lesions of the pancreas (p<0.05). CONCLUSION Both imaging techniques well correlate to final diagnosis of non-metastatic solid pancreatic lesions and particularly of adenocarcinomas with a slight advantage for mangafodipir trisodium-enhanced magnetic resonance imaging plus MR cholangiopancreatography.
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Affiliation(s)
- P Boraschi
- 2nd Department of Radiology, Pisa University Hospital, Via Paradisa 2, 56124 Pisa, Italy.
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ROMANO L, GRAZIOLI L, BONOMO L, XU JR, CHEN KM, DORE R, VANZULLI A, CATALANO C. Enhancement and safety of iomeprol-400 and iodixanol-320 in patients undergoing abdominal multidetector CT. Br J Radiol 2009; 82:204-11. [DOI: 10.1259/bjr/93627766] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Phillips TJ, Stella DL, Rozen WM, Ashton M, Taylor GI. Abdominal wall CT angiography: a detailed account of a newly established preoperative imaging technique. Radiology 2008; 249:32-44. [PMID: 18796666 DOI: 10.1148/radiol.2483072054] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Institutional review board approval was obtained for this study, and all patients gave written informed consent. Autologous surgical breast reconstruction with use of abdominal wall donor flaps based on the deep inferior epigastric artery (DIEA) and one or more of its anterior musculocutaneous perforating branches (DIEA perforator flap) is being used with increasing frequency instead of breast reconstruction with use of traditional transverse rectus abdominus musculocutaneous and modified muscle-sparing flaps. Preoperative mapping of the DIEA perforators with abdominal wall computed tomographic (CT) angiography may improve patient care by providing the surgeon with additional information that will lead to optimization of the surgical technique, shorter procedure time, and reduction in the frequency of surgical complications. The branching patterns of the DIEA, the segmental anatomy of the anterior adipocutaneous perforating branches of the DIEA, and the importance of these features in pre- and intraoperative surgical planning necessitate a different approach to abdominal wall CT angiography than that used with other abdominal CT angiographic techniques. In abdominal wall CT angiography, the common femoral artery is used as the bolus trigger, CT scanning is performed in the caudocranial direction, the automatic exposure control feature is disabled, a scaled grid overlay tool is used to present information to the surgeons, and radiation dose is minimized (average dose, 6 mSv). The anatomic accuracy of abdominal wall CT angiography has been investigated in cadaveric and surgical studies, with sensitivity of 96%-100% and specificity of 95%-100%. This detailed description will allow other radiologists and surgeons interested in free DIEP flap surgery to incorporate this useful tool into their practice.
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Affiliation(s)
- Timothy J Phillips
- Department of Radiology, the Royal Melbourne Hospital, Grattan Street, Parkville, Melbourne, Victoria 3050, Australia.
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Multiple-detector computed tomographic angiography of pancreatic neoplasm for presurgical planning: comparison of low- and high-concentration nonionic contrast media. J Comput Assist Tomogr 2008; 32:511-7. [PMID: 18664834 DOI: 10.1097/rct.0b013e31813ffd12] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the degree of contrast enhancement, image quality, and accuracy of predicting resectability of pancreatic neoplasm with 16-row multiple-detector computed tomography (MDCT) angiography using low- and high-concentration (300 and 370 mg of iodine per milliliter, respectively) contrast media (CMs). MATERIALS AND METHODS Forty patients who had undergone pancreatic CT angiography (CTA) on 16-MDCT scanner and had surgery were included. Contrast medium of 2 iodine concentrations (group A, 300 mg/mL, n = 20; group B, 370 mg/mL, n = 20) from the same vendor (Isovue; Bracco Diagnostics), with iodine dose of 550 to 600 mg/kg of body weight, was injected at a rate of 5 mL/s. Dual-phase 16-row MDCT was performed using 1.25- and 5-mm collimation for the arterial and portal phases, respectively. For the quantitative analysis, Hounsfield units values in the aorta, superior mesenteric artery, portal vein, and pancreas during arterial and venous phases were measured. Two readers subjectively rated the overall image enhancement, 3-dimensional image quality, and lesion and pancreatic duct conspicuity. Accuracy of lesion resectability was also established for each patient. The data were compared using Student t test for statistical analysis. RESULTS The quantitative analysis for the degree of enhancement (Hounsfield unit) of the aorta, superior mesenteric artery, and pancreas during the arterial phase demonstrated similar values in groups A (low-concentration CM) and B (high-concentration CM), with no statistically significant difference with each other (P > 0.05). During the portal venous phase, we found superior enhancements in the superior mesenteric and portal veins in group A (P < 0.05). The qualitative assessments of the overall image enhancement and 3-dimensional image quality on a 5-point scale were 4.3 and 4.65, respectively (P < 0.05), in group A and 4.6 and 4.75, respectively, in group B, whereas on a 3-point scale, the pancreatic duct display and lesion conspicuity were 2.75 and 2.85, respectively, in group A and 2.9 and 2.9, respectively, in group B. The accuracy for lesion resectability was 95% (19/20) in group A and 100% (20/20) in group B (P > 0.05). CONCLUSION Both CMs demonstrated comparable performance for 16-row MDCT of the pancreas for presurgical planning. However, high-concentration CM (370 mg of iodine per milliliter) provides higher overall enhancement and superior-quality 3-dimensional images with a shorter injection duration.
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Fukukura Y, Hamada H, Kamiyama T, Yoneyama T, Takumi K, Nakajo M. Pancreatic adenocarcinoma: analysis of the effect of various concentrations of contrast material. RADIATION MEDICINE 2008; 26:355-361. [PMID: 18677610 DOI: 10.1007/s11604-008-0240-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2007] [Accepted: 02/29/2008] [Indexed: 05/26/2023]
Abstract
PURPOSE The aim of this study was to compare the efficacy of two contrast materials with moderate and high iodine concentrations for the depiction of pancreatic adenocarcinoma. MATERIALS AND METHODS A series of 107 patients with histologically proven pancreatic adenocarcinoma underwent helical computed tomography. A fixed dose of 100 ml of iopamidol 300 (mg I/ml) was administered to 50 patients (group A) and iopamidol 370 (mg I/ml) to 57 patients (group B) at the same injection rate (3 ml/s). Unenhanced helical scans and contrast-enhanced scans for three phases (30, 70, and 300 s after starting the infusion of contrast material) were obtained. We evaluated enhancement of the aorta, portal vein, hepatic parenchyma, pancreatic parenchyma, and pancreatic adenocarcinoma during each phase. RESULTS During all phases, both aortic and pancreatic enhancement were significantly greater in group B than in group A (P<0.01). Enhancement of the portal vein and hepatic parenchyma was significantly greater at 70 and 300 s in group B than in group A (both P<0.01). Tumor-to-pancreas contrast was significantly greater in group B than in group A at both 30 s (P<0.01) and 70 s (P<0.05). CONCLUSION Administration of contrast material with a high iodine concentration is more effective for depicting pancreatic adenocarcinomas.
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Affiliation(s)
- Yoshihiko Fukukura
- Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan.
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Mancosu P, Bettinardi V, Passoni P, Gusmini S, Cappio S, Gilardi MC, Cattaneo GM, Reni M, Del Maschio A, Di Muzio N, Fazio F. Contrast enhanced 4D-CT imaging for target volume definition in pancreatic ductal adenocarcinoma. Radiother Oncol 2008; 87:339-42. [PMID: 18486253 DOI: 10.1016/j.radonc.2008.04.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 04/08/2008] [Accepted: 04/19/2008] [Indexed: 11/16/2022]
Abstract
A procedure to improve target volume definition in pancreatic ductal adenocarcinoma by contrast enhanced 4D-CT imaging has been implemented for radiotherapy planning. The procedure allows good quality images to be obtained over the whole patient's breathing cycle in terms of anatomical details, pancreatic enhancement and vessel definition.
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Secretin-assisted CT of the pancreas: improved pancreatic enhancement and tumour conspicuity. Clin Radiol 2008; 63:401-6. [DOI: 10.1016/j.crad.2007.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Revised: 10/03/2007] [Accepted: 10/04/2007] [Indexed: 10/22/2022]
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MAI WILFRIED, CÁCERES ANAV. DUAL-PHASE COMPUTED TOMOGRAPHIC ANGIOGRAPHY IN THREE DOGS WITH PANCREATIC INSULINOMA. Vet Radiol Ultrasound 2008; 49:141-8. [DOI: 10.1111/j.1740-8261.2008.00340.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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A Comparison of the Efficacy and Safety of Iopamidol-370 and Iodixanol-320 in Patients Undergoing Multidetector-Row Computed Tomography. Invest Radiol 2007; 42:856-61. [DOI: 10.1097/rli.0b013e3181514413] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yanaga Y, Awai K, Nakayama Y, Nakaura T, Tamura Y, Hatemura M, Yamashita Y. Pancreas: patient body weight tailored contrast material injection protocol versus fixed dose protocol at dynamic CT. Radiology 2007; 245:475-82. [PMID: 17890356 DOI: 10.1148/radiol.2452061749] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE To prospectively compare the effect of a protocol with a fixed contrast material injection dose and one with a dose tailored to patient body weight on pancreatic enhancement at dynamic computed tomography (CT) of the pancreas. MATERIALS AND METHODS This study was approved by the institutional review board, and patients gave informed consent. Seventy-eight patients suspected of having pancreatic tumor were randomly assigned to one of two protocols (39 patients in each protocol). In protocol 1, a fixed contrast material dose (120 mL of iohexol 300) was delivered at an injection rate of 4.0 mL/sec; in protocol 2, a dose tailored to the patient's body weight (2.0 mL/kg) was injected over the course of 30 seconds. Scans were started 25, 45 (pancreatic parenchymal phase [PPP]), and 70 (portal venous phase [PVP]) seconds after the initiation of contrast material injection. Pancreatic enhancement during the PPP and hepatic enhancement during the PVP were compared by using the Student t test in patients whose body weight was less than 60 kg (group A) or 60 kg or greater (group B). A radiologist who was blinded to the injection protocol used measured the CT number of each organ. RESULTS With protocol 1, mean pancreatic enhancement during the PPP was 94.1 HU in group A and 76.1 HU in group B; the difference was statistically significant (P = .02). With protocol 2, mean pancreatic enhancement was 89.5 HU in group A and 84.7 HU in group B; there was no significant difference (P = .45). Mean hepatic enhancement with protocol 1 during the PVP was 59.6 HU in group A and 48.5 HU in group B (P < .01); with protocol 2, it was 55.4 HU in group A and 58.3 HU in group B. The difference was not statistically significant (P = .34). CONCLUSION The dose protocol tailored to the patient's body weight yielded satisfactory pancreatic and hepatic enhancement irrespective of patient weight.
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Affiliation(s)
- Yumi Yanaga
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto, Japan
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Iseri T, Yamada K, Chijiwa K, Nishimura R, Matsunaga S, Fujiwara R, Sasaki N. Dynamic computed tomography of the pancreas in normal dogs and in a dog with pancreatic insulinoma. Vet Radiol Ultrasound 2007; 48:328-31. [PMID: 17691631 DOI: 10.1111/j.1740-8261.2007.00251.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
To establish optimal imaging conditions for enhanced computed tomography (CT) for canine pancreatic tumors, 10 healthy beagles were subjected to dynamic CT. This technique was then applied to a dog with suspected insulinoma. The changes in mean peak enhancement and the delay time of the aorta and pancreas were determined. In normal beagles, maximal arterial and pancreatic CT enhancement was observed at 15 +/- 2 s (795 +/- 52 Housfield unit [HU]) and 28 +/- 9 s (118 +/- 16HU) after contrast medium injection, respectively. Multiphase enhanced CT was performed in a pug with suspected insulinoma using the CT protocol defined for the normal beagles with some parameters modified; the images were acquired at the arterial (14 s after contrast medium injection), pancreatic (after 28 s), and equilibrium (after 90 s) phases; scanning was followed by exploratory laparotomy. CT images were characterized by an enhanced mass in the left pancreatic lobe at the arterial phase, during which the difference between the CT values of the mass and normal pancreas was the highest. Histopathologic diagnosis of the pancreatic mass was insulinoma. Thus, it appears that enhanced CT imaging can be used to delineate the pancreas from a pancreatic mass, and it may be helpful in deciding the need for surgery.
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Affiliation(s)
- Toshie Iseri
- Laboratories of Veterinary Surgery, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-I Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Rau MM, Setty BN, Blake MA, Ouellette-Piazzo K, Hahn PF, Sahani DV. Evaluation of Renal Transplant Donors with 16-Section Multidetector CT Angiography: Comparison of Contrast Media with Low and High Iodine Concentrations. J Vasc Interv Radiol 2007; 18:603-9. [PMID: 17494841 DOI: 10.1016/j.jvir.2007.02.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
PURPOSE To compare the degree of contrast enhancement, image quality, and accuracy of renal computed tomographic (CT) angiography performed with a 16-detector row CT unit and equal iodine doses of low- and high-iodine-concentration contrast medium in the evaluation of renal transplant donors. MATERIALS AND METHODS Eighty donors scheduled to undergo renal CT angiography with 16-detector row CT were administered nonionic contrast media with two iodine concentrations. The first group (group A, n=40) received a contrast medium with 300 mg of iodine per milliliter, and the second group (group B, n=40) received a contrast medium with 370 mg of iodine per milliliter. An equal iodine dose of 550 mg per kilogram body weight was given to both groups. Contrast enhancement was quantified by measuring attenuation in the abdominal aorta and in both renal arteries. Subjective assessment of contrast enhancement, quality of reformatted images, and visualization of branch order of renal arteries were rated with a 5-point scale. The number of renal arteries and veins seen at CT was correlated with the results at surgery. RESULTS The mean enhancement values in group B were significantly greater (P<.001) than those in group A. The mean HU (+/-standard deviation) in groups A and B were 298+/-76 and 344+/-75, respectively, in the aorta, 284+/-74 and 331+/-71 in the right renal artery, and 285+/-72 and 329+/-73 in the left renal artery. The mean enhancement, image quality, and branch orders visualized were rated better in group B than in group A (P<.01). The accuracies for correctly identifying renal arteries and veins, respectively, were 91% and 95% for group A and 96% and 96% for group B. CONCLUSION Renal donor CT angiography with a contrast medium of 370 mg of iodine per milliliter provides greater enhancement and image quality compared with a contrast medium of 300 mg of iodine per milliliter. The diagnostic accuracies were similar.
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Affiliation(s)
- Matthew M Rau
- Department of Radiology, Division of Abdominal Imaging and Interventional Radiology, Massachusetts General Hospital, White 270, 55 Fruit St, Boston, MA 02114, USA
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Jakobsen JA. Physiological effects of contrast media for use in multidetector row computed tomography. Eur J Radiol 2007. [DOI: 10.1016/j.ejrad.2007.02.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Abstract
The most common imaging modality used for diagnosis of aortic disease is CT, followed by transesophageal echocardiography, MRI, and aortography. If multiple imaging is performed, the initial imaging technique most frequently employed is computerized tomography. During the past decade, computed tomographic angiography (CTA) has become a standard non-invasive imaging modality for the depiction of vascular anatomy and pathology. The quality and speed of CTA examinations have increased dramatically as CT technology has evolved from-channel spiral CT systems to multichannel (4-, 8-, 10- and 16-slice) spiral CT system. The quality and speed of CTA is superior to other imaging modalities, and it is also cheaper and less invasive. CTA of the aorta has proven to be superior in diagnostic accuracy to conventional arteriography in several applications.
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Affiliation(s)
- Tongfu Yu
- Radiological Department of the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
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Nagamoto M, Gomi T, Terada H, Terada S, Kohda E. Evaluation of the acute adverse reaction of contrast medium with high and moderate iodine concentration in patients undergoing computed tomography. ACTA ACUST UNITED AC 2006; 24:669-74. [PMID: 17186321 DOI: 10.1007/s11604-006-0087-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Accepted: 08/07/2006] [Indexed: 10/23/2022]
Abstract
PURPOSE The aim of this prospective study was to evaluate and compare acute adverse reactions between contrast medium containing moderate and high concentrations of iodine in patients undergoing computed tomography (CT). MATERIALS AND METHODS A total of 945 patients undergoing enhanced CT were randomly assigned to receive one of two doses of contrast medium. We then prospectively investigated the incidence of adverse reactions. Iopamidol was used as the contrast medium, with a high concentration of 370 mg I/ml and a moderate concentration of 300 mg I/ml. The frequency of adverse reactions, such as pain at the injection site and heat sensation, were determined. RESULTS Acute adverse reactions were observed in 2.4% (11/458) of the moderate-concentration group compared to 3.11% (15/482) of the high-concentration group; there was no significant difference in incidence between the two groups. Most adverse reactions were mild, and there was no significant difference in severity. One patient in the high-concentration group was seen to have a moderate adverse reaction. No correlation existed between the incidence of adverse reactions and patient characteristics such as sex, age, weight, flow amount, and flow rate. The incidence of pain was not significantly different between the two groups. In contrast, the incidence of heat sensation was significantly higher in the high-concentration group. CONCLUSIONS The incidence and severity of acute adverse reactions were not significantly different between the two groups, and there were no severe adverse reactions in either group.
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Affiliation(s)
- Masashi Nagamoto
- Department of Radiology, School of Medicine, Toho University, 2-17-6 Ohashi, Meguro-ku, Tokyo 153-1251, Japan.
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Johnson PT, Fishman EK. IV Contrast Selection for MDCT: Current Thoughts and Practice. AJR Am J Roentgenol 2006; 186:406-15. [PMID: 16423946 DOI: 10.2214/ajr.04.1902] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE The purpose of this article is to review studies evaluating how contrast concentration affects MDCT of the body and to report IV contrast infusion protocols from MDCT angiography and MDCT of abdominal tumors. CONCLUSION Higher concentrations (350 mg I/mL or greater) may improve visualization of small abdominal arteries. However, preliminary data comparing 300 mg I/mL to higher concentrations for MDCT of hypervascular hepatocellular carcinoma and pancreatic cancer have shown that higher concentrations may not increase tumor conspicuity.
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Affiliation(s)
- Pamela T Johnson
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, 601 N Caroline St., Rm. 3251, Baltimore, MD 21287
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Schoellnast H, Brader P, Oberdabernig B, Pisail B, Deutschmann HA, Fritz GA, Schaffler G, Tillich M. High-Concentration Contrast Media in Multiphasic Abdominal Multidetector-Row Computed Tomography. J Comput Assist Tomogr 2005; 29:582-7. [PMID: 16163023 DOI: 10.1097/01.rct.0000175502.79954.96] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The purpose of this study was to assess the influence of the iodine flow rate on parenchymal and vascular enhancement during multiphasic abdominal multidetector-row computed tomography (MDCT). METHODS Fifteen patients underwent MDCT at an iodine flow rate of 1.2 g/s as well as 1.6 g/s (group A, protocols 1 and 2), and 90 patients underwent MDCT at an iodine flow rate of 1.2 g/s (group B) or 1.6 g/s (group C). Measurements were performed for all groups in the liver, spleen, pancreas, portal vein, inferior vena cava, and abdominal aorta. RESULTS Aortal and pancreatic enhancement during the arterial phase was significantly higher with the higher iodine flow rate. The mean difference in aortal enhancement was 60 Hounsfield units (HU) between protocols 1 and 2 of group A, and the mean difference was 70 HU between groups B and C. The mean difference in pancreatic enhancement was 10 HU between protocols 1 and 2 of group A and 17 HU between groups B and C. During the portal and hepatic venous phases, no significant difference in enhancement was observed. CONCLUSION A high iodine flow rate in multiphasic abdominal MDCT improves enhancement of the aorta and the pancreas during the arterial phase but does not influence later phases.
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Affiliation(s)
- Helmut Schoellnast
- Department of Radiology, Medical University and University Hospital Graz, Graz, Austria.
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