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Fu Q, Lei ZQ, Li JY, Wu JW, Liu XM, Fan WL, Sun P, Wang JZ, Liu DX, Yang F, Zheng CS, Kong XC. Subtractionless compressed-sensing-accelerated whole-body MR angiography using two-point Dixon fat suppression with single-pass half-reduced contrast dose: feasibility study and initial experience. J Cardiovasc Magn Reson 2023; 25:41. [PMID: 37475047 PMCID: PMC10360239 DOI: 10.1186/s12968-023-00953-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 07/10/2023] [Indexed: 07/22/2023] Open
Abstract
PURPOSE To investigate the feasibility and clinical utility of a compressed-sensing-accelerated subtractionless whole-body MRA (CS-WBMRA) protocol with only contrast injection for suspected arterial diseases, by comparison to conventional dual-pass subtraction-based whole-body MRA (conventional-WBMRA) and available computed tomography angiography (CTA). MATERIALS AND METHODS This prospective study assessed 86 patients (mean age, 56 years ± 16.4 [standard deviation]; 25 women) with suspected arterial diseases from May 2021 to December 2022, who underwent CS-WBMRA (n = 48, mean age, 55.9 years ± 16.4 [standard deviation]; 25 women) and conventional-WBMRA (n = 38, mean age, 48 years ± 17.4 [standard deviation]; 20 women) on a 3.0 T MRI after random group assignment based on the chronological order of enrolment. Of all enrolled patients administered the CS-WBMRA protocol, 35% (17/48) underwent CTA as required by clinical demands. Two experienced radiologists independently scored the qualitative image quality and venous enhancement contamination. Quantitative image assessment was carried out by determining and comparing the apparent signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of four representative arterial segments. The total examination time and contrast-dose were also recorded. The independent samples t-test or the Wilcoxon rank sum test was used for statistical analysis. RESULTS The overall scores of CS-WBMRA outperformed those of conventional-WMBRA (3.40 ± 0.60 vs 3.22 ± 0.55, P < 0.001). In total, 1776 and 1406 arterial segments in the CS-WBMRA and conventional-WBMRA group were evaluated. Qualitative image scores for 7 (of 15) vessel segments in the CS-WMBRA group had statistically significantly increased values compared to those of the conventional-WBMRA groups (P < 0.05). Scores from the other 8 segments showed similar image quality (P > 0.05) between the two protocols. In the quantitative analysis, overall apparent SNRs were significantly higher in the conventional-WBMRA group than in the CS-WBMRA group (214.98 ± 136.05 vs 164.90 ± 118.05; P < 0.001), while overall apparent CNRs were not significantly different in these two groups (CS vs conventional: 107.13 ± 72.323 vs 161.24 ± 118.64; P > 0.05). In the CS-WBMRA group, 7 of 1776 (0.4%) vessel segments were contaminated severely by venous enhancement, while in the convention-WBMRA group, 317 of 1406 (23%) were rated as severe contamination. In the CS-WBMRA group, total examination and reconstruction times were only 7 min and 10 min, respectively, vs 20 min and < 30 s for the conventional WBMRA group, respectively. The contrast agent dose used in the CS-WBMRA protocol was reduced by half compared to conventional-WBMRA protocol (18.7 ± 3.5 ml vs 37.2 ± 5.4 ml, P = 0.008). CONCLUSION The CS-WBMRA protocol provides excellent image quality and sufficient diagnostic accuracy for whole-body arterial disease, with relatively faster workflow and half-dose reduction of contrast agent, which has greater potential in clinical practice compared with conventional-WBMRA.
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Affiliation(s)
- Qing Fu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Zi-Qiao Lei
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Jing-Yang Li
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Jia-Wei Wu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Xiao-Ming Liu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Wen-Liang Fan
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Peng Sun
- Philips Healthcare, Beijing, 100600, China
| | | | - Ding-Xi Liu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Fan Yang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Chuan-Sheng Zheng
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China.
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China.
| | - Xiang-Chuang Kong
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue #1277, Wuhan, 430022, Hubei Province, China.
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China.
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Kwee RM, Kwee TC. Whole-body MRI for preventive health screening: A systematic review of the literature. J Magn Reson Imaging 2019; 50:1489-1503. [PMID: 30932247 PMCID: PMC6850647 DOI: 10.1002/jmri.26736] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/19/2019] [Accepted: 03/19/2019] [Indexed: 12/19/2022] Open
Abstract
Background The yield of whole‐body MRI for preventive health screening is currently not completely clear. Purpose To systematically review the prevalence of whole‐body MRI findings in asymptomatic subjects. Study Type Systematic review and meta‐analysis. Subjects MEDLINE and Embase were searched for original studies reporting whole‐body MRI findings in asymptomatic adults without known disease, syndrome, or genetic mutation. Twelve studies, comprising 5373 asymptomatic subjects, were included. Field Strength/Sequence 1.5T or 3.0T, whole‐body MRI. Assessment The whole‐body MRI literature findings were extracted and reviewed by two radiologists in consensus for designation as either critical or indeterminate incidental finding. Statistical Tests Data were pooled using a random effects model on the assumption that most subjects had ≤1 critical or indeterminate incidental finding. Heterogeneity was assessed by the I2 statistic. Results Pooled prevalences of critical and indeterminate incidental findings together and separately were 32.1% (95% confidence interval [CI]: 18.3%, 50.1%), 13.4% (95% CI: 9.0%, 19.5%), and 13.9% (95% CI: 5.4%, 31.3%), respectively. There was substantial between‐study heterogeneity (I2 = 95.6–99.1). Pooled prevalence of critical and indeterminate incidental findings together was significantly higher in studies that included (cardio)vascular and/or colon MRI compared with studies that did not (49.7% [95% CI, 26.7%, 72.9%] vs. 23.0% [95% CI, 5.5%, 60.3%], P < 0.001). Pooled proportion of reported verified critical and indeterminate incidental findings was 12.6% (95% CI: 3.2%, 38.8%). Six studies reported false‐positive findings, yielding a pooled proportion of 16.0% (95% CI: 1.9%, 65.8%). None of the included studies reported long‐term (>5‐year) verification of negative findings. Only one study reported false‐negative findings, with a proportion of 2.0%. Data Conclusion Prevalence of critical and indeterminate incidental whole‐body MRI findings in asymptomatic subjects is overall substantial and with variability dependent to some degree on the protocol. Verification data are lacking. The proportion of false‐positive findings appears to be substantial. Level of Evidence: 4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:1489–1503.
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Affiliation(s)
- Robert M Kwee
- Department of Radiology and Nuclear Medicine, Zuyderland Medical Center, Heerlen/Sittard/Geleen, The Netherlands
| | - Thomas C Kwee
- Department of Radiology, Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands
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Zaki MM, Hegazy EA, Abdelhamid MI, El-Mogy SA. The role of parallel imaging technique in decreasing geometric distortion artifact in diffusion weighted imaging of the brain. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2018. [DOI: 10.1016/j.ejrnm.2018.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Lambert MA, Weir-McCall JR, Salsano M, Gandy SJ, Levin D, Cavin I, Littleford R, MacFarlane JA, Matthew SZ, Nicholas RS, Struthers AD, Sullivan F, Henderson SA, White RD, Belch JJF, Houston JG. Prevalence and Distribution of Atherosclerosis in a Low- to Intermediate-Risk Population: Assessment with Whole-Body MR Angiography. Radiology 2018; 287:795-804. [PMID: 29714681 PMCID: PMC5979784 DOI: 10.1148/radiol.2018171609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Purpose To quantify the burden and distribution of asymptomatic atherosclerosis in a population with a low to intermediate risk of cardiovascular disease. Materials and Methods Between June 2008 and February 2013, 1528 participants with 10-year risk of cardiovascular disease less than 20% were prospectively enrolled. They underwent whole-body magnetic resonance (MR) angiography at 3.0 T by using a two-injection, four-station acquisition technique. Thirty-one arterial segments were scored according to maximum stenosis. Scores were summed and normalized for the number of assessable arterial segments to provide a standardized atheroma score (SAS). Multiple linear regression was performed to assess effects of risk factors on atheroma burden. Results A total of 1513 participants (577 [37.9%] men; median age, 53.5 years; range, 40-83 years) completed the study protocol. Among 46 903 potentially analyzable segments, 46 601 (99.4%) were interpretable. Among these, 2468 segments (5%) demonstrated stenoses, of which 1649 (3.5%) showed stenosis less than 50% and 484 (1.0%) showed stenosis greater than or equal to 50%. Vascular stenoses were distributed throughout the body with no localized distribution. Seven hundred forty-seven (49.4%) participants had at least one stenotic vessel, and 408 (27.0%) participants had multiple stenotic vessels. At multivariable linear regression, SAS correlated with age (B = 3.4; 95% confidence interval: 2.61, 4.20), heart rate (B = 1.23; 95% confidence interval: 0.51, 1.95), systolic blood pressure (B = 0.02; 95% confidence interval: 0.01, 0.03), smoking status (B = 0.79; 95% confidence interval: 0.44, 1.15), and socioeconomic status (B = -0.06; 95% confidence interval: -0.10, -0.02) (P < .01 for all). Conclusion Whole-body MR angiography identifies early vascular disease at a population level. Although disease prevalence is low on a per-vessel level, vascular disease is common on a per-participant level, even in this low- to intermediate-risk cohort. © RSNA, 2018 Online supplemental material is available for this article.
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Affiliation(s)
| | | | - Marco Salsano
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Stephen J. Gandy
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Daniel Levin
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Ian Cavin
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Roberta Littleford
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Jennifer A. MacFarlane
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Shona Z. Matthew
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Richard S. Nicholas
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Allan D. Struthers
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Frank Sullivan
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Shelley A. Henderson
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Richard D. White
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - Jill J. F. Belch
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
| | - J. Graeme Houston
- From the Division of Molecular and Clinical Medicine, College of
Medicine, University of Dundee, Level 7, Ninewells Hospital, Dundee DD1 9SY,
Scotland (M.A.L., J.R.W.M., M.S., D.L., R.L., S.Z.M., A.D.S., J.J.F.B., J.G.H.);
NHS Tayside Medical Physics, Ninewells Hospital, Dundee, Scotland (S.J.G., I.C.,
J.A.M., R.S.N., S.A.H.); Department of Research and Innovation, North York
General Hospital, University of Toronto, Toronto, Canada (F.S.); and Department
of Clinical Radiology, University Hospital of Wales, Cardiff, Wales
(R.D.W.)
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Ulus S, Suleyman E, Ozcan UA, Karaarslan E. Whole-Body MRI Screening in Asymptomatic Subjects; Preliminary Experience and Long-Term Follow-Up Findings. Pol J Radiol 2016; 81:407-14. [PMID: 27635171 PMCID: PMC5008738 DOI: 10.12659/pjr.897570] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 01/25/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The aim of this study is to describe the technique and to evaluate the results of whole-body magnetic resonance imaging in an asymptomatic population. MATERIAL/METHODS Between March 2009 and December 2011, 118 consecutive subjects undergoing thorough medical check-up were prospectively included in the study. MRI was performed with a 205-cm moving table, parallel imaging and automatic image composing software. RESULTS In 83 subjects (70%), 103 benign lesions were detected. Two malignant (adrenal and renal carcinoma) lesions and one precancerous (pancreatic mucinous carcinoma) lesion were detected. The most common lesions were renal cysts, liver hemangiomas, liver cysts, thyroid nodules, and uterine leiomyomas. CONCLUSIONS WB-MRI is able to cover area from head to toes in one diagnostic work-up, and besides the anatomic regions evaluated by conventional radiological modalities, i.e. brain parenchyma, bones and extremities, can be evaluated in one examination.
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Affiliation(s)
- Sila Ulus
- Department of Radiology, Acıbadem University, School of Medicine, Istanbul, Turkey
| | - Erdogan Suleyman
- Department of Radiology, Acıbadem Maslak Hospital, Istanbul, Turkey
| | - Umit Aksoy Ozcan
- Department of Radiology, Acıbadem University, School of Medicine, Istanbul, Turkey
| | - Ercan Karaarslan
- Department of Radiology, Acıbadem University, School of Medicine, Istanbul, Turkey
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Tsao TF, Cheng KL, Shen CY, Wu MC, Huang HH, Su CH, Chen FL, Tyan YS, Lin YC. Diagnostic Performance of Combined Contrast-Enhanced Magnetic Resonance Angiography and Phase-Contrast Magnetic Resonance Imaging in Suspected Subclavian Steal Syndrome. Can Assoc Radiol J 2016; 67:190-201. [PMID: 26831732 DOI: 10.1016/j.carj.2015.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 07/30/2015] [Accepted: 08/01/2015] [Indexed: 11/25/2022] Open
Abstract
PURPOSE The study sought to evaluate the efficacy of magnetic resonance imaging (MRI) in patients with suspected subclavian steal syndrome (SSS) using both contrast-enhanced (CE) MR angiography and phase-contrast (PC) MRI. METHODS Fifteen suspected SSSs from 13 patients were evaluated using CE-MR angiography and PC-MRI. Ten patients also received dynamic CE-MR angiography. RESULTS All MRI examinations were technically successful. By combining CE-MR angiography with PC-MRI, 10 SSSs were diagnosed in 9 patients. The delay enhancement dynamic technique predicted SSS with a sensitivity, specificity, and accuracy of 57.1%, 100%, and 72.7%, respectively. Without the dynamic technique, affected delay-enhanced arteries were poorly visualized and could be mistaken for occluded vessels. Retrograde vertebral flow by PC-MRI was used to predict ipsilateral SSS with a sensitivity, specificity, and accuracy of 100%, 60%, and 86.7%, respectively. There were 2 false positives including 1 patient with a proximal total occlusion of the affected vertebral artery and another with brachiocephalic steal syndrome rather than SSS. This suggested that retrograde vertebral flow does not always indicate SSS. CONCLUSIONS CE-MR angiography combined with PC-MRI is efficacious when evaluating SSS in clinical practice.
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Affiliation(s)
- Teng-Fu Tsao
- Department of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan, Republic of China; Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, Republic of China
| | - Kai-Lun Cheng
- Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, Republic of China
| | - Chao-Yu Shen
- Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, Republic of China
| | - Ming-Chi Wu
- Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, Republic of China
| | - Hsin-Hui Huang
- Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, Republic of China
| | - Chun-Hung Su
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan, Republic of China; Division of Cardiology, Department of Internal Medicine, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China
| | - Fong-Lin Chen
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan, Republic of China; Division of Pediatric Cardiology, Department of Pediatrics, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China
| | - Yeu-Sheng Tyan
- Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China; School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, Republic of China
| | - Yung-Chang Lin
- Department of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan, Republic of China; Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China.
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Tarnoki DL, Tarnoki AD, Richter A, Karlinger K, Berczi V, Pickuth D. Clinical value of whole-body magnetic resonance imaging in health screening of general adult population. Radiol Oncol 2015; 49:10-6. [PMID: 25810696 PMCID: PMC4362601 DOI: 10.2478/raon-2014-0031] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 06/18/2014] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Whole-body magnetic resonance imaging (WB-MRI) and angiography (WB-MRA) has become increasingly popular in population-based research. We evaluated retrospectively the frequency of potentially relevant incidental findings throughout the body. MATERIALS AND METHODS 22 highly health-conscious managers (18 men, mean age 47±9 years) underwent WB-MRI and WB-MRA between March 2012 and September 2013 on a Discovery MR750w wide bore 3 Tesla device (GE Healthcare) using T1 weighted, short tau inversion recovery (STIR) and diffusion weighted imaging (DWI) acquisitions according to a standardized protocol. RESULTS A suspicious (pararectal) malignancy was detected in one patient which was confirmed by an endorectal sonography. Incidental findings were described in 20 subjects, including hydrocele (11 patients), benign bony lesion (7 patients) and non-specific lymph nodes (5 patients). Further investigations were recommended in 68% (ultrasound: 36%, computed tomography: 28%, mammography: 9%, additional MRI: 9%). WB-MRA were negative in 16 subjects. Vascular normal variations were reported in 23%, and a 40% left proximal common carotid artery stenosis were described in one subject. CONCLUSIONS WB-MRI and MRA lead to the detection of clinically relevant diseases and unexpected findings in a cohort of healthy adults that require further imaging or surveillance in 68%. WB-MR imaging may play a paramount role in health screening, especially in the future generation of (epi)genetic based screening of malignant and atherosclerotic disorders. Our study is the first which involved a highly selected patient group using a high field 3-T wide bore magnet system with T1, STIR, MRA and whole-body DWI acquisitions as well.
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Affiliation(s)
- David Laszlo Tarnoki
- Department of Diagnostic and Interventional Radiology, Caritasklinikum Saarbrücken St. Theresia, Academic Teaching Hospital of Saarland University, Saarbrücken, Germany
- Department of Radiology and Oncotherapy, Semmelweis University School of Medicine, Budapest, Hungary
| | - Adam Domonkos Tarnoki
- Department of Diagnostic and Interventional Radiology, Caritasklinikum Saarbrücken St. Theresia, Academic Teaching Hospital of Saarland University, Saarbrücken, Germany
- Department of Radiology and Oncotherapy, Semmelweis University School of Medicine, Budapest, Hungary
| | - Antje Richter
- Department of Diagnostic and Interventional Radiology, Caritasklinikum Saarbrücken St. Theresia, Academic Teaching Hospital of Saarland University, Saarbrücken, Germany
| | - Kinga Karlinger
- Department of Radiology and Oncotherapy, Semmelweis University School of Medicine, Budapest, Hungary
| | - Viktor Berczi
- Department of Radiology and Oncotherapy, Semmelweis University School of Medicine, Budapest, Hungary
| | - Dirk Pickuth
- Department of Diagnostic and Interventional Radiology, Caritasklinikum Saarbrücken St. Theresia, Academic Teaching Hospital of Saarland University, Saarbrücken, Germany
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Bamberg F, Parhofer KG, Lochner E, Marcus RP, Theisen D, Findeisen HM, Hoffmann U, Schönberg SO, Schlett CL, Reiser MF, Weckbach S. Diabetes Mellitus: Long-term Prognostic Value of Whole-Body MR Imaging for the Occurrence of Cardiac and Cerebrovascular Events. Radiology 2013; 269:730-7. [DOI: 10.1148/radiol.13130371] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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9
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Miquel M, Blackall J, Uribe S, Hawkes D, Schaeffter T. Patient-specific respiratory models using dynamic 3D MRI: Preliminary volunteer results. Phys Med 2013; 29:214-20. [DOI: 10.1016/j.ejmp.2012.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 02/24/2012] [Accepted: 03/05/2012] [Indexed: 01/28/2023] Open
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10
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Riffel P, Haneder S, Attenberger UI, Brade J, Schoenberg SO, Michaely HJ. Combined large field-of-view MRA and time-resolved MRA of the lower extremities: Impact of acquisition order on image quality. Eur J Radiol 2012; 81:2754-8. [DOI: 10.1016/j.ejrad.2011.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 12/01/2011] [Indexed: 11/25/2022]
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11
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Laible M, Schoenberg SO, Weckbach S, Lettau M, Winnik E, Bischof J, Franke R, Reiser M, Kramer H. Whole-body MRI and MRA for evaluation of the prevalence of atherosclerosis in a cohort of subjectively healthy individuals. Insights Imaging 2012; 3:485-93. [PMID: 22836780 PMCID: PMC3443278 DOI: 10.1007/s13244-012-0180-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 05/23/2012] [Accepted: 06/04/2012] [Indexed: 01/07/2023] Open
Abstract
Objectives To assess the prevalence of cardiovascular findings in asymptomatic individuals by means of 1.5-T whole-body magnetic resonance imaging and angiography. Methods A cohort of 138 individuals (118 men, 20 women) with a mean age of 54 years (SD ± 7.55) was referred to whole-body MRI at 1.5-T, including contrast-enhanced whole-body MR angiography (MRA) and cardiac MRI. A total of 2,065/2,070 vessel segments (99.8%) and cardiac function were evaluated. Results Approximately one-fourth of the participating individuals had vascular abnormalities. In 17 subjects (12.3% of all subjects) significant luminal narrowing was observed in at least one vascular segment. Luminal narrowing (mild to severe) was observed in 1 (0.7% of all subjects respectively) of the renal arteries, 7 (5.0%) of the carotid arteries, and 3 (2.2%) of the pelvic and upper leg arteries, and in 17 segments (12.3%) of arteries in the lower leg. In cardiac function and perfusion imaging, wall motion disorders were observed in six patients (4.3%), with additional delayed enhancement and isolated delayed enhancement present in two cases. Functional parameters differed from reference values in 55 cases. Conclusions Even in an asymptomatic cohort of middle-aged predominantly male individuals, atherosclerotic disease is not uncommon and is detectable by whole-body MRI. Main Messages In middle-aged predominantly male individuals, atherosclerotic disease is not uncommon. Even in an asymptomatic collective, approximately one fourth had vascular abnormalities. Using whole-body MR angiography (MRA), 99.8% of 2,070 vessel segments could be evaluated.
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Affiliation(s)
- M Laible
- Department of Clinical Radiology, University Hospital Munich, Grosshadern Campus, Munich, Germany,
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Haneder S, Attenberger UI, Riffel P, Henzler T, Schoenberg SO, Michaely HJ. Magnetic resonance angiography (MRA) of the calf station at 3.0 T: intraindividual comparison of non-enhanced ECG-gated flow-dependent MRA, continuous table movement MRA and time-resolved MRA. Eur Radiol 2011; 21:1452-61. [DOI: 10.1007/s00330-011-2063-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 12/04/2010] [Accepted: 12/13/2010] [Indexed: 12/01/2022]
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13
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Attenberger UI, Haneder S, Morelli JN, Diehl SJ, Schoenberg SO, Michaely HJ. Peripheral Arterial Occlusive Disease: Evaluation of a High Spatial and Temporal Resolution 3-T MR Protocol with a Low Total Dose of Gadolinium versus Conventional Angiography. Radiology 2010; 257:879-87. [DOI: 10.1148/radiol.10100781] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Morin S, Cobbold J, Lim A, Eliahoo J, Thomas E, Mehta S, Durighel G, Fitzpatrick J, Bell J, Taylor-Robinson S. Incidental findings in healthy control research subjects using whole-body MRI. Eur J Radiol 2009; 72:529-33. [DOI: 10.1016/j.ejrad.2008.08.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 07/14/2008] [Accepted: 08/12/2008] [Indexed: 12/21/2022]
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15
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Lehrke S, Egenlauf B, Steen H, Lossnitzer D, Korosoglou G, Merten C, Ivandic BT, Giannitsis E, Katus HA. Prediction of coronary artery disease by a systemic atherosclerosis score index derived from whole-body MR angiography. J Cardiovasc Magn Reson 2009; 11:36. [PMID: 19761595 PMCID: PMC2758875 DOI: 10.1186/1532-429x-11-36] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2009] [Accepted: 09/17/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Whole-body magnetic resonance angiography (WB-MRA) has shown its potential for the non-invasive assessment of nearly the entire arterial vasculature within one examination. Since the presence of extra-cardiac atherosclerosis is associated with an increased risk of coronary events, our goal was to establish the relationship between WB-MRA findings, including a systemic atherosclerosis score index, and the presence of significant coronary artery disease (CAD). METHODS WB-MRA was performed on a 1.5T scanner in 50 patients scheduled to undergo elective cardiac catheterization for suspected CAD. In each patient, 40 extra-cardiac vessel segments were evaluated and assigned scores according to their luminal narrowing. The atherosclerosis score index (ASI) was generated as the ratio of summed scores to analyzable segments. RESULTS ASI was higher in patients with significant (> 50% stenosis) CAD (n = 27) vs. patients without CAD (n = 22; 1.56 vs. 1.28, p = 0.004). ASI correlated with PROCAM (R = 0.57, p < 0.001) and Framingham (R = 0.36, p = 0.01) risk scores as estimates of the 10-year risk of coronary events. A ROC derived ASI of > 1.54 predicted significant CAD with a sensitivity of 59%, specificity of 86% and a positive predictive value of 84%. Logistic regression revealed ASI > 1.54 as the strongest independent predictor for CAD with a 11-fold increase in likelihood to suffer from significant coronary disease. On the contrary, while 15/27 (55%) of patients with CAD exhibited at least one extra-cardiac stenosis > 50%, only 3/22 (14%) of those patients without CAD did (p = 0.003). The likelihood for an extra-cardiac stenosis when CAD is present differed between vascular territories and ranged from 15% for a carotid stenosis to 44% for a stenosis in the lower extremities. CONCLUSION This study provides important new evidence for the close association of extra-cardiac and coronary atherosclerosis. The novel findings that a WB-MRA derived systemic atherosclerosis score index is not only associated with established cardiovascular risk scores but is also predictive of significant CAD suggest its potential prognostic implications and underline the importance to screen for coronary disease in patients with extra-cardiac manifestations of atherosclerosis.
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Affiliation(s)
- Stephanie Lehrke
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Benjamin Egenlauf
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Henning Steen
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Dirk Lossnitzer
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Grigorius Korosoglou
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Constanze Merten
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Boris T Ivandic
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Evangelos Giannitsis
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - Hugo A Katus
- Abteilung Innere Medizin III, Medizinische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Germany
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Peripheral Magnetic Resonance Angiography With Continuous Table Movement in Combination With High Spatial and Temporal Resolution Time-Resolved MRA With a Total Single Dose (0.1 mmol/kg) of Gadobutrol at 3.0 T. Invest Radiol 2009; 44:627-33. [DOI: 10.1097/rli.0b013e3181b4c26c] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kramer H, Nikolaou K, Reiser MF. Cardiovascular whole-body MRI. Eur J Radiol 2009; 70:418-23. [PMID: 19442468 DOI: 10.1016/j.ejrad.2009.03.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Accepted: 03/16/2009] [Indexed: 12/01/2022]
Abstract
Cardiovascular diseases still rank number one in mortality statistics in the industrialized world. In these countries the five most common causes of death are associated to atherosclerotic changes of the arterial vasculature. Due to its often long lasting treatment and the possible loss of ability to work atherosclerotic disease constitutes an economic factor which should not be disregarded. Thus screening for atherosclerotic disease seems to be reasonable because as known the potential to influence atherosclerotic changes is higher in an early stage of the disease. Not in every case it is possible to cure the disease but sometimes progression can be controlled and decelerated. Imaging of the arterial vasculature was limited to invasive procedures associated with ionizing radiation for a long time. Non-invasive exams like the "ankle-brachial-index" (ABI) can indicate the presence of PAOD, an exact localization of the pathologic changes is only possible with imaging methods. For cardiac imaging likewise the only non-invasive exams have been ECG and auscultation. Certainly echocardiography is an excellent technique to access cardiac function but it depends very much on both, the examining physician and the patient. MRI constitutes a non-invasive imaging modality without ionizing radiation offering excellent reproducible image quality.
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Affiliation(s)
- Harald Kramer
- Department of Clinical Radiology, University Hospitals Munich, Grosshadern Campus, Ludwig Maxmilians University Munich, Marchioninistr. 15, 81377 Munich, Germany.
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Abstract
Diabetes mellitus is a major cardiovascular risk factor and one of the major causes for morbidity and mortality worldwide. Diabetic complications have not only major impact on the quality of life of diabetic patients, but are also potentially life-threatening. Therefore prevention, diagnosis and therapy of these long-term complications are of high importance. However, diagnosis of the variety of complications from diabetes mellitus remains a diagnostic challenge and usually several diagnostic steps are necessary to diagnose or exclude these complications. In the last years whole body magnetic resonance imaging (WB-MRI) including whole body magnetic resonance angiography (WB-MRA) has been introduced for cardiovascular imaging and is now increasingly applied in clinical routine for the workup of patients with cardiovascular disease and for cardiovascular screening. The article summarizes rationales for WB-MRI in diabetes mellitus, technical concepts of disease specific cardiovascular WB-MRI in diabetes mellitus and discusses potential clinical consequences.
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20
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Systemic Cardiovascular Complications in Patients With Long-Standing Diabetes Mellitus. Invest Radiol 2009; 44:242-50. [DOI: 10.1097/rli.0b013e31819a60d3] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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21
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Fenchel M, Doering J, Seeger A, Kramer U, Rittig K, Klumpp B, Claussen CD, Miller S. Ultrafast Whole-Body MR Angiography with Two-dimensional Parallel Imaging at 3.0 T: Feasibility Study. Radiology 2009; 250:254-63. [DOI: 10.1148/radiol.2501080494] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Seeger A, Kramer U, Fenchel M, Grimm F, Bretschneider C, Döring J, Klumpp B, Tepe G, Rittig K, Seidensticker PR, Claussen CD, Miller S. Comparison between a linear versus a macrocyclic contrast agent for whole body MR angiography in a clinical routine setting. J Cardiovasc Magn Reson 2008; 10:63. [PMID: 19116027 PMCID: PMC2633332 DOI: 10.1186/1532-429x-10-63] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2008] [Accepted: 12/30/2008] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Previous experiences of whole body MR angiography are predominantly available in linear 0.5 M gadolinium-containing contrast agents. The aim of this study was to compare image quality on a four-point scale (range 1-4) and diagnostic accuracy of a 1.0 M macrocyclic contrast agent (gadobutrol, n = 80 patients) with a 0.5 M linear contrast agent (gadopentetate dimeglumine, n = 85 patients) on a 1.5 T whole body MR system. Digital subtraction angiography served as standard of reference. RESULTS All examinations yielded diagnostic image quality. There was no significant difference in image quality (3.76 +/- 0.3 versus 3.78 +/- 0.3, p = n.s.) and diagnostic accuracy observed. Sensitivity and specificity of the detection of hemodynamically relevant stenoses was 93%/95% in the gadopentetate dimeglumine group and 94%/94% in the gadobutrol group, respectively. CONCLUSION The high diagnostic accuracy of gadobutrol in the clinical routine setting is of high interest as medical authorities (e.g. the European Agency for the Evaluation of Medicinal Products) recommend macrocyclic contrast agents especially to be used in patients with renal failure or dialysis.
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Affiliation(s)
- Achim Seeger
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Ulrich Kramer
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Michael Fenchel
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Florian Grimm
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Christiane Bretschneider
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Jörg Döring
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Bernhard Klumpp
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Gunnar Tepe
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Kilian Rittig
- Department of Internal Medicine IV, Eberhard-Karls-University Tuebingen, Otfried-Müller-Str. 10, 72076 Tuebingen, Germany
| | | | - Claus D Claussen
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
| | - Stephan Miller
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
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Assessment and reproducibility of aortic atherosclerosis magnetic resonance imaging: impact of 3-Tesla field strength and parallel imaging. Invest Radiol 2008; 43:656-62. [PMID: 18708860 DOI: 10.1097/rli.0b013e318181538a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To investigate image quality and interstudy reproducibility of aortic atherosclerosis imaging at 1.5 T, and to explore the impact of parallel imaging techniques at 3 T. MATERIALS AND METHODS Institutional review board approval and informed consent were obtained. Thirty-two subjects (20 normal, 12 patients with impaired cardiac function) underwent 4 black-blood T2-weighted imaging studies of the abdominal aorta: 2 conventional studies at 1.5 T, a conventional study at 3 T, and an accelerated 3-T study with parallel imaging (SENSE). Contrast-to-noise ratio and image quality score (1-5 scale, 5 = highest quality) were determined for each study. Studies were analyzed for mean wall thickness and area plaque burden as endpoints for aortic atherosclerosis. Bland-Altman analyses were performed to determine interstudy reproducibility between imaging methods. Wilcoxon signed-rank tests were used to identify significant differences between methods (P < 0.05). RESULTS Image quality scores were comparable between 1.5 T and 3 T with SENSE (4.0 +/- 0.6 vs. 4.2 +/- 0.6, P = 0.21). Bland-Altman reproducibility for mean wall thickness was -0.03 mm +/- 0.15 (1.5 T vs. 1.5 T), 0.01 mm +/- 0.17 (1.5 T vs. 3 T without SENSE), and -0.01 mm +/- 0.18 (1.5 T vs. 3 T with SENSE), P = 0.83. Detection of the presence or absence of plaque was comparable. Bland-Altman reproducibility for area plaque burden was -0.02% +/- 0.32% (1.5 T vs. 1.5 T), 0.06% +/- 0.41% (1.5 T vs. 3 T without SENSE), and 0.11% +/- 0.33% (1.5 T vs. 3 T with SENSE), P = 0.41. CONCLUSION Black-blood MR imaging of aortic atherosclerosis is very reproducible. Parallel imaging at 3 T permits shorter scan time compared with conventional 1.5-T imaging with comparable measures of atherosclerosis extent.
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Abstract
Gadofosveset (Vasovist®, Bayer Schering Pharma AG, Berlin/Germany) is the first intravascular contrast agent approved for use with magnetic resonance angiography in the European Union, Switzerland, Turkey, Canada, and Australia. Gadofosveset reversibly binds to albumin providing extended intravascular enhancement compared wth existing extracellular magnetic resonance contrast agents. Prior to approval, gadofosveset underwent extensive testing to evaluate the safety and efficacy of the drug; the clinical trials show that gadofosveset-enhanced magnetic resonance angiography (MRA) is safe and well tolerated in patients with vascular disease and effective for the detection of vascular stenosis and aneurysms gadofosveset has the potential to open new horizons in diagnostic MRA by increasing the spatial resolution and the robustness of MRA examinations and facilitating the examination of multiple vascular beds.
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Affiliation(s)
- Mathias Goyen
- University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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Peripheral Magnetic Resonance Angiography (MRA) With Continuous Table Movement at 3.0 T. Invest Radiol 2008; 43:627-34. [PMID: 18708856 DOI: 10.1097/rli.0b013e31817e90e9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Nael K, Krishnam M, Nael A, Ton A, Ruehm SG, Finn JP. Peripheral contrast-enhanced MR angiography at 3.0T, improved spatial resolution and low dose contrast: initial clinical experience. Eur Radiol 2008; 18:2893-900. [DOI: 10.1007/s00330-008-1074-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2008] [Accepted: 06/05/2008] [Indexed: 11/28/2022]
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Whole-Body MRA. Eur Radiol 2008; 18:1925-36. [DOI: 10.1007/s00330-007-0817-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2007] [Revised: 10/17/2007] [Accepted: 10/24/2007] [Indexed: 01/10/2023]
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Whole-body magnetic resonance angiography at 3.0 Tesla. Eur Radiol 2008; 18:1473-83. [DOI: 10.1007/s00330-008-0885-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2007] [Revised: 12/01/2007] [Accepted: 01/16/2008] [Indexed: 11/26/2022]
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Efficient whole-body MRI interpretation: evaluation of a dedicated software prototype. J Digit Imaging 2008; 21 Suppl 1:S50-8. [PMID: 18266034 DOI: 10.1007/s10278-008-9107-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2007] [Revised: 12/14/2007] [Accepted: 01/15/2008] [Indexed: 10/22/2022] Open
Abstract
The study investigates the performance of a dedicated whole-body magnetic resonance imaging (MRI) interpretation software with regard to diagnostic efficiency using quantitative and qualitative parameters. Forty-eight oncologic patients underwent whole-body computed tomography (WB-CT) and whole-body magnetic resonance imaging (WB-MRI). In a quantitative analysis, the times needed for interpretation of the CT and MRI datasets were measured. The MRI studies were read using a standard workstation and the whole-body MRI interpretation software, respectively. In the qualitative analysis, the numbers of metastases were separately recorded for 13 organ systems, again interpreting the MRI images on the standard workstation and with the dedicated software. Moreover, user friendliness and system usability were evaluated using a standardized questionnaire. Use of the whole-body MRI interpretation software significantly reduced the MRI interpretation time compared with the standard workstation. There was no significant difference between interpretation time of WB-CT and interpretation time of WB-MRI using the dedicated software. Comparison with WB-CT as the reference method demonstrated no significant difference between the whole-body MRI interpretation software prototype and the standard interpretation software in the number of metastases detected. In conclusion, the use of the dedicated whole-body reading software improves the interpretation process of WB-MRI studies with respect to time efficiency and system usability.
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Riederer SJ, Hu HH, Kruger DG, Haider CR, Campeau NG, Huston J. Intrinsic signal amplification in the application of 2D SENSE parallel imaging to 3D contrast-enhanced elliptical centric MRA and MRV. Magn Reson Med 2008; 58:855-64. [PMID: 17969124 DOI: 10.1002/mrm.21282] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The relative signal-to-noise ratio (SNR) provided by 2D sensitivity encoding (SENSE) when applied to 3D contrast-enhanced MR angiography (CE-MRA) is studied. If an elliptical centric phase-encoding order is used to map the waning magnetization of the contrast bolus to k-space, the application of SENSE will reduce the degree of k-space signal modulation, providing a signal amplification A over corresponding nonaccelerated acquisitions. This offsets the SNR loss in R-accelerated SENSE due to suquare root R and the geometry (g) factor. The theoretical bound on A is R and is reduced from this depending on the properties of the bolus profile and the duration over which it is imaged. In this work a signal amplification of 1.14-1.23 times that of nonvascular background tissue is demonstrated in a study of 20 volunteers using R = 4 2D SENSE whole-brain MR venography (MRV). The effects of a nonuniform g-factor and inhomogeneity of background tissue are accounted for. The observed amplification compares favorably with the value of 1.31 predicted numerically from a measured bolus curve.
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Kramer H, Weckbach S, van Kaick G, Reiser MF, Schoenberg SO. [Screening in cardiovascular diseases]. Radiologe 2008; 48:52-62. [PMID: 18210053 DOI: 10.1007/s00117-007-1607-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cardiovascular disease still ranks number one in the mortality statistics in the industrialized world. In Germany the five most common causes of death are all associated with arteriosclerotic changes of the arterial vasculature. As the treatment often extends over long periods and it can be impossible for patients to work, peripheral arterial occlusive disease (PAOD) constitutes a not inconsiderable economic factor. Thus, screening for arteriosclerotic disease seems to be reasonable, because the potential for influencing arteriosclerotic changes is known to be higher in an early stage of the disease even before symptoms become apparent. Not every case can be cured, but progression can frequently be slowed down. The need for invasive procedures, some of them associated with ionizing radiation, limited the use of imaging of the arterial vasculature for a long time. Noninvasive clinical examinations such as the "ankle brachial index" (ABI) can indicate the presence of PAOD, though exact localization of the pathologic changes is not possible except with imaging methods. In contrast to these, MRI is a noninvasive imaging modality that does not involve ionizing radiation but offers high spatial resolution arterial imaging.
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Affiliation(s)
- H Kramer
- Institut für Klinische Radiologie, Klinikum Grosshadern der Ludwig-Maximilians-Universität München, München, Deutschland.
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Niendorf T, Sodickson DK. Highly accelerated cardiovascular MR imaging using many channel technology: concepts and clinical applications. Eur Radiol 2008; 18:87-102. [PMID: 17562047 PMCID: PMC2838248 DOI: 10.1007/s00330-007-0692-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2006] [Revised: 04/26/2007] [Accepted: 05/10/2007] [Indexed: 01/23/2023]
Abstract
Cardiovascular magnetic resonance imaging (CVMRI) is of proven clinical value in the non-invasive imaging of cardiovascular diseases. CVMRI requires rapid image acquisition, but acquisition speed is fundamentally limited in conventional MRI. Parallel imaging provides a means for increasing acquisition speed and efficiency. However, signal-to-noise (SNR) limitations and the limited number of receiver channels available on most MR systems have in the past imposed practical constraints, which dictated the use of moderate accelerations in CVMRI. High levels of acceleration, which were unattainable previously, have become possible with many-receiver MR systems and many-element, cardiac-optimized RF-coil arrays. The resulting imaging speed improvements can be exploited in a number of ways, ranging from enhancement of spatial and temporal resolution to efficient whole heart coverage to streamlining of CVMRI work flow. In this review, examples of these strategies are provided, following an outline of the fundamentals of the highly accelerated imaging approaches employed in CVMRI. Topics discussed include basic principles of parallel imaging; key requirements for MR systems and RF-coil design; practical considerations of SNR management, supported by multi-dimensional accelerations, 3D noise averaging and high field imaging; highly accelerated clinical state-of-the art cardiovascular imaging applications spanning the range from SNR-rich to SNR-limited; and current trends and future directions.
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Affiliation(s)
- Thoralf Niendorf
- Department of Diagnostic Radiology, RWTH Aachen, University Hospital, Pauwelsstrasse 30, 52057 Aachen, Germany, Tel.: +49-241-8080295, Fax: +49-241-803380295
| | - Daniel K. Sodickson
- Department of Radiology, Center for Biomedical Imaging, New York University, School of Medicine, 650 First Avenue, Suite 600-A, New York, NY, 10016, USA, Tel.: 212-263-4844, Fax: 212-263-4845
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Dellegrottaglie S, Sanz J, Macaluso F, Einstein AJ, Raman S, Simonetti OP, Rajagopalan S. Technology Insight: magnetic resonance angiography for the evaluation of patients with peripheral artery disease. ACTA ACUST UNITED AC 2007; 4:677-87. [PMID: 18033232 DOI: 10.1038/ncpcardio1035] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Accepted: 09/03/2007] [Indexed: 12/21/2022]
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Goyen M. MR angiography with Vasovist®. Radiography (Lond) 2007. [DOI: 10.1016/j.radi.2007.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Nael K, Fenchel MC, Kramer U, Finn JP, Ruehm SG, Gruehm S. Whole-body contrast-enhanced magnetic resonance angiography: new advances at 3.0 T. Top Magn Reson Imaging 2007; 18:127-34. [PMID: 17621226 DOI: 10.1097/rmr.0b013e318093e6d9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
During the past decade, technical improvements and numerous advances in scanner hardware and software have significantly improved image quality, speed, and reliability of 3-dimensional (3-D) contrast-enhanced magnetic resonance angiography (CE-MRA). The accuracy of CE-MRA is now comparable with that of computed tomography angiography or even conventional catheter angiography. Peripheral vascular disease (PVD) accounts for 50,000 to 60,000 cases of percutaneous transluminal angioplasty and for about 100,000 cases of amputation annually in the United States. Proper treatment of the arterial disease requires a comprehensive assessment of the underlying vascular morphology because it is crucial to localize and gauge the severity of arterial lesions for further therapeutic decision making.Contrast-enhanced magnetic resonance angiography has been widely implemented in noninvasive evaluation of PVD with high diagnostic accuracy. The lack of ionizing radiation and the use of contrast agent with relatively small potential nephrotoxicity in population of PVD with high prevalence of renal impairment are the appealing features for broad acceptance of CE-MRA in initial diagnosis and repeated follow-up studies of patients with PVD. The minimum anatomical coverage for evaluation of PVD comprises the aortic bifurcation to the ankles; however, because of the systemic nature of atherosclerosis hypertension, renal or cerebrovascular disease frequently coexist. Thus, many clinicians regard evaluation of the whole-body arterial vasculature as desirable.
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Affiliation(s)
- Kambiz Nael
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA 90095-7206, USA.
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Hansen T, Ahlström H, Johansson L. Whole-body screening of atherosclerosis with magnetic resonance angiography. Top Magn Reson Imaging 2007; 18:329-337. [PMID: 18025987 DOI: 10.1097/rmr.0b013e318159aaa2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
With whole-body magnetic resonance angiography (WBMRA), it is possible to examine the whole arterial tree except intracranial and coronary vessels in a single examination without the risks involved in ionizing radiation or arterial cannulation. Whole-body magnetic resonance angiography is well suited for repeated clinical examinations in patients with systemic diseases such as vasculitis or atherosclerosis and can also be used for scientific purposes. On the basis of the WBMRA overview, a possible further development of the WBMRA concept can be to perform further acquisitions at sites with atherosclerotic plaques with higher-resolution scans to determine the degree of stenosis more accurately or to achieve plaque characterization. A total validation of WBMRA compared with digital subtraction angiography (DSA) is not possible owing to the hazards of ionizing radiation. Studies have shown a high sensitivity and specificity for the pelvic and lower limb arteries in comparison with DSA. No systematic validation against DSA has been performed for the renal, aortic, and carotid arteries. Various methods have been used, however, for confirmation of vascular abnormalities found on WBMRA such as ultrasonography, dedicated MRA, or DSA, with reasonably high agreement. The WBMRA method has not been studied with regard to prediction of future cardiovascular (CV) events, as have intima media thickness, coronary artery calcium scoring, and the ankle-brachial index. The full usefulness of WBMRA in an epidemiological setting and as a complementary screening tool for assessing CV risk still needs to be validated against future CV events.
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Affiliation(s)
- Tomas Hansen
- Department of Radiology, Uppsala University Hospital, Uppsala, Sweden.
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37
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Fink C, Thieme S, Ley S, Clevert D, Reiser MF, Kauczor HU, Schoenberg SO. MRT der akuten Lungenembolie. Radiologe 2007; 47:708-15. [PMID: 17673970 DOI: 10.1007/s00117-007-1532-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Recent technical developments have substantially improved the potential of MRI for the diagnosis of pulmonary embolism. On the MR scanner side this includes the development of short magnets and dedicated whole-body MRI systems, which allow a comprehensive evaluation of pulmonary embolism and deep venous thrombosis in a single exam. The introduction of parallel imaging has substantially improved the spatial and temporal resolution of pulmonary MR angiography. By combining time-resolved pulmonary perfusion MRI with high-resolution pulmonary MRA a sensitivity and specificity of over 90% is achievable, which is comparable to the accuracy of CTA. Thus, for certain patient groups, such as patients with contraindications to iodinated contrast media and young women with a low clinical probability for pulmonary embolism, MRI can be considered as a first-line imaging tool for the assessment of pulmonary embolism.
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Affiliation(s)
- C Fink
- Institut für Klinische Radiologie, Universitätsklinikum Mannheim, Medizinische Fakultät Mannheim der Universität Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
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Theisen D, Wintersperger BJ, Huber A, Dietrich O, Reiser MF, Schönberg SO. Myocardial First Pass Perfusion Imaging With Gadobutrol. Invest Radiol 2007; 42:522-8. [PMID: 17568275 DOI: 10.1097/rli.0b013e3180383572] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To implement parallel imaging algorithms in fast gradient recalled echo sequences for myocardial perfusion imaging and evaluate image quality, signal-to-noise ratio (SNR), contrast-enhancement ratio (CER), and semiquantitative perfusion parameters. MATERIALS AND METHODS In 20 volunteers, myocardial perfusion imaging with gadobutrol was performed at rest using an accelerated TurboFLASH sequence (TR 2.3 milliseconds, TE 0.93 milliseconds, flip angle [FA] 15 degrees) with GRAPPA, R=2. A nonaccelerated TurboFLASH sequence with similar scan parameters served as standard of reference. Artifacts were assessed qualitatively. SNR, CER, and CNR were calculated and semiquantitative perfusion parameters were determined from fitted SI-time curves. RESULTS Phantom measurements yielded significant higher SNR for nonaccelerated images (P<0.001). CER was equal; differences in CNR were statistically nonsignificant. The evaluation of semiquantitative perfusion parameters yielded significantly higher peak signal intensities in nonaccelerated images (P<0.001). Differences in maximum upslope were statistically nonsignificant. A qualitative examination of all images for artifacts by 2 board-certified radiologists yielded a significant reduction in dark rim artifacts with GRAPPA, R=2 (P<0.001). CONCLUSIONS The application of GRAPPA with an acceleration factor of R=2 leads to a significant reduction of dark rim artifacts in fast gradient recalled echo sequences.
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Affiliation(s)
- Daniel Theisen
- Department of Clinical Radiology, Campus Grosshadern, Ludwig-Maximilians-University, Munich, Germany.
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Theisen D, Wintersperger BJ, Huber A, Dietrich O, Reiser MF, Schönberg SO. Myocardial Perfusion Imaging With Gadobutrol: A Comparison Between 3 and 1.5 Tesla With an Identical Sequence Design. Invest Radiol 2007; 42:499-506. [PMID: 17568272 DOI: 10.1097/rli.0b013e3180339981] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To implement myocardial first-pass perfusion imaging at 3 Tesla and to evaluate the potential benefit with regard to signal parameters in comparison to 1.5 Tesla using identical sequence settings and an intraindividual comparison. MATERIALS AND METHODS In 16 volunteers, myocardial first-pass perfusion imaging was performed at 1.5 Tesla (Magnetom Avanto) and 3 Tesla (Magnetom TIM Trio) after injection of 0.05 mmol/kg body weight Gadobutrol using an accelerated saturation recovery TurboFLASH technique (GRAPPA; R=2) at 1.5 and 3 Tesla. Detailed sequence parameters (TR 2.3 milliseconds, TE 0.93 milliseconds, flip angle 15 degrees , bandwidth 780 Hz/px) as well as spatial resolution were kept identical for both field strengths. Artifacts were assessed quantitatively and qualitatively, signal-to-noise ratio (SNR) and contrast enhancement ratio (CER) were calculated from raw data signal intensity-time curves. A linear fit on the upslope was performed for semiquantitative perfusion analysis. RESULTS SNR was significantly higher at 3 Tesla than at 1.5 Tesla (35.7+/-11.9 vs. 18.0+/-5.5, P<0.001). CER was significantly greater at 3 Tesla than at 1.5 Tesla (2.2+/-0.9 vs. 1.4+/-0.5, P<0.001). Maximum upslope was significantly higher at 3 Tesla than at 1.5 Tesla (3.3+/-2.4 vs. 2.0+/-1.0, P<0.001). A qualitative examination of all images for artifacts by 2 board-certified radiologists yielded no significant differences between the field strengths. CONCLUSIONS Three Tesla significantly improves CER and SNR compared with 1.5 Tesla with identical sequence parameters. In addition, the most important semiquantitative perfusion parameter maximum upslope is significantly increased. This may allow for an improvement of spatial resolution and potentially for a better delineation of perfusion defects. However, further studies are necessary to potentially demonstrate a benefit of 3 Tesla perfusion imaging in a clinical setting.
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Affiliation(s)
- Daniel Theisen
- Department of Clinical Radiology, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Munich, Germany.
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40
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Ladd SC, Ladd ME. Perspectives for preventive screening with total body MRI. Eur Radiol 2007; 17:2889-97. [PMID: 17549492 DOI: 10.1007/s00330-007-0657-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 02/19/2007] [Accepted: 03/27/2007] [Indexed: 10/23/2022]
Abstract
Radiology has started to increasingly recognise its potential for screening with the advent of "whole-body" imaging techniques. This article briefly reviews prerequisites for successful screening, presents a quick summary of single-organ screening with magnetic resonance (MR) imaging, and introduces how this knowledge can be integrated into whole-body MR (wb-MR) screening. MR colonography has demonstrated its potential for screening. Wb-MR in the form of wb-MR angiography has already entered both clinical and screening settings; also, the search for metastases with wb-MR has been evaluated and has performed well when compared with other imaging modalities. But screening a group of healthy subjects requires more than feasibility and high accuracy of the screening test; thus, technical and ethical considerations are also presented. Wb-MR is only at its beginning and will in the near future certainly inspire many new research activities as well as transform the radiological market.
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Affiliation(s)
- Susanne C Ladd
- Department of Diagnostic and Interventional Radiology, University Hospital Essen, Hufelandstrasse 55, 45122, Essen, Germany.
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41
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Schmidt GP, Wintersperger B, Graser A, Baur-Melnyk A, Reiser MF, Schoenberg SO. High-Resolution Whole-Body Magnetic Resonance Imaging Applications at 1.5 and 3 Tesla. Invest Radiol 2007; 42:449-59. [PMID: 17507818 DOI: 10.1097/01.rli.0000262089.55618.18] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To analyze the impact of altered magnetic field properties on image quality and on potential artifacts when an established whole-body magnetic resonance imaging (WB-MRI) protocol at 1.5 Tesla (T) is migrated to 3 T. MATERIALS AND METHODS Fifteen volunteers underwent noncontrast magnetic resonance imaging (MRI) on 32-channel whole body-scanners at 1.5 and 3 T with the use of parallel acquisition techniques (PAT). Coronal T1-weighted TSE- and short tau inversion recovery (STIR)-sequences at 4 body levels including sagittal imaging of the whole spine were performed. Additional axial HASTE-imaging of lung and abdomen, T1-/T2-weighted-TSE- and EPI-sequences of the brain and T2-weighted respiratory-triggered imaging of the liver was acquired. Both data sets were compared by 2 independent readers in respect to artifacts and image quality using a 5-point scale. Regions of pronounced artifacts were defined. RESULTS Overall image impression was both qualitatively rated as "good" at 1.5 and 3 T for T1-w-TSE- and STIR-imaging of the whole body and spine. At 1.5 T, significantly better quantitative values for overall image quality were found for WB-STIR, T2-w-TSE imaging of the liver and brain (Wilcoxon Mann-Whitney U Test; P < 0.05), overall rated as good at 3 T. Significantly higher dielectric effects at 3 T were affecting T1-w- and STIR-WB-MRI, and HASTE of the abdomen and better image homogeneity at 1.5 T was observed for T1-weighted-/STIR-WB-MRI and T1-w-TSE-imaging of the spine. Pulsation artifacts were significantly increased at 3 T for T1-w WB-MRI. Significantly higher susceptibility artifacts were found for GRE-sequences of the brain at 3 T. Motion artifacts, Gibbs-Ringing, and image distortion was not significantly different and showed slightly higher quantitative values at 3 T (except for HASTE imaging of the abdomen). Overall scan time was 45 minutes and 44 seconds at 1.5 T and 40 minutes and 28 seconds at 3 T at identical image resolution. CONCLUSION Three Tesla WB-MRI is feasible with good image quality comparable to 1.5 T. 3.0 T WB-MRI shows significantly more artifacts with a mild to moderate impact on image assessment. Therefore 1.5 T WB-MRI is the preferred image modality. Overall scan time at 3 T is reduced with the use of parallel imaging at a constant image resolution.
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Affiliation(s)
- Gerwin P Schmidt
- Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, LMU, Munich, Germany.
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Ho LM, Merkle EM, Paulson EK, Dale BM. Contrast-enhanced hepatic magnetic resonance angiography at 3 T: does parallel imaging improve image quality? J Comput Assist Tomogr 2007; 31:177-80. [PMID: 17414749 DOI: 10.1097/01.rct.0000243441.72620.ce] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate whether hepatic magnetic resonance angiography (MRA) performed at 3 T and acquired with a parallel imaging acceleration factor of 2 provides satisfactory image quality and adequate contrast-to-noise, compared with an acquisition without parallel imaging. MATERIALS AND METHODS Ten volunteers underwent both a standard (A) and an experimental (B) MRA protocol. Both protocols used a gadoteridol dose of 20 mL injected at 2 mL/s in a 3-T magnetic resonance (MR) system. Protocol B was identical to protocol A, except protocol B was performed with a parallel imaging acceleration factor of 2. Contrast-to-noise ratios (CNRs) were calculated in the suprarenal abdominal aorta, the common hepatic artery, and the right and left hepatic arteries. The same 4 vessels were rated for quality of arterial visualization using a 5-point scale (1 = poor to 5 = excellent). The paired t test and Wilcoxon rank sum test were used for statistical analysis. RESULTS The CNRs and qualitative scores were higher in all 4 vessels using protocol B. Mean CNRs in the suprarenal abdominal aorta, common hepatic artery, and the right and left hepatic arteries were 31, 33, 28, and 22 for protocol A and 36, 40, 36, and 25 for protocol B, respectively (P < 0.05 except the left hepatic arteries [P = 0.35]). Mean qualitative scores of the same vessels were 4.3, 3.7, 3.1, and 2.9 using protocol A and 4.4, 3.8, 3.5, and 3.2 for protocol B, respectively (P > 0.44). CONCLUSIONS Parallel imaging performed in a 3-T MR system improves hepatic MRA both quantitatively and qualitatively.
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Affiliation(s)
- Lisa M Ho
- Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
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43
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Treitl M, Ruppert V, Mayer AK, Degenhart C, Reiser M, Rieger J. [Chronic critical ischemia of the lower leg: pretherapeutic imaging and methods for revascularization]. Radiologe 2007; 46:962-72. [PMID: 17021909 DOI: 10.1007/s00117-006-1423-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Each year 1-2% of patients with peripheral arterial occlusive disease (pAOD) develop critical limb ischemia (CLI), characterized by rest pain and peripheral ulcer or gangrene. This aggravation of the disease is accompanied by an increase of the 1-year mortality rate up to 25% and a similarly increased frequency of major amputation. We can choose between conservative, endovascular, and surgical procedures for an adequate therapy of the underlying vascular stenoses or occlusions. Yet, clear therapeutic recommendations only exist for suprapopliteal lesions. However, in a number of cases, especially in diabetics, target lesions have an infrapopliteal location. Since endovascular procedures have undergone significant improvement in the last few years, the following review discusses methods for infrapopliteal revascularization taking into consideration the newest publications on this topic.
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Affiliation(s)
- M Treitl
- Institut für Klinische Radiologie, Innenstadt-Klinikum der Ludwig-Maximilians-Universität, Pettenkoferstrasse 8a, 80336 Munich, Germany.
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Hansen T, Wikström J, Johansson LO, Lind L, Ahlström H. The Prevalence and Quantification of Atherosclerosis in an Elderly Population Assessed by Whole-Body Magnetic Resonance Angiography. Arterioscler Thromb Vasc Biol 2007; 27:649-54. [PMID: 17170372 DOI: 10.1161/01.atv.0000255310.47940.3b] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The principal aim of the present study was to explore the feasibility of using whole-body magnetic resonance angiography to assess atherosclerosis in different vascular territories in a cohort of elderly. METHODS AND RESULTS Three hundred six 70-year-old subjects (145 women, 161 men) recruited from a population-based cohort study (Prospective Investigation of the Vasculature in Uppsala Seniors, ie, the PIVUS study) underwent 1.5-T whole-body magnetic resonance angiography with gadodiamide. The arteries were divided into 26 segments. In total, 7956 vessel segments were evaluated with 7900 segments (99.3%) possible to evaluate. Of these, 7186 segments (91%) were normal. Luminal narrowing of > or = 50% was observed in 9 (1.5%) of the renal arteries, 12 (1.8%) of the carotid arteries, in 31 segments (1.1%) of the pelvic/upper leg territories, and in 136 segments (6.2%) of territories in the lower leg. Approximately one-third of the sample had no vascular abnormalities, one-third had stenoses of < 50%, and the remainder had stenoses > or = 50% or occlusions. Six subjects (2%) had aortic aneurysms. In subjects without evident vascular disease, 26% had significant vascular abnormalities. CONCLUSIONS Whole-body magnetic resonance angiography performed with a clinical scanner can be used for quantifying atherosclerosis in different vascular territories in a single examination in an elderly population.
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Affiliation(s)
- T Hansen
- Institution of ORKI, Department of Radiology, Uppsala University Hospital, SE-751 85 Uppsala, Sweden.
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Nael K, Fenchel M, Krishnam M, Laub G, Finn JP, Ruehm SG. High-Spatial-Resolution Whole-Body MR Angiography with High-Acceleration Parallel Acquisition and 32-Channel 3.0-T Unit: Initial Experience. Radiology 2007; 242:865-72. [PMID: 17325071 DOI: 10.1148/radiol.2423060135] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this HIPAA-compliant study was to prospectively evaluate the technical feasibility of a multistation high-spatial-resolution whole-body magnetic resonance (MR) angiography protocol in which high-acceleration parallel imaging (with acceleration factors of three and four) is performed with a 32-channel 3.0-T MR system. After institutional review board approval and written informed consent were obtained, 10 healthy volunteers (four men and six women aged 23-68 years) and four patients (two men and two women aged 56-79 years) suspected of having peripheral vascular disease underwent multistation whole-body contrast material-enhanced MR angiography. Use of multiarray surface coil technology and highly accelerated generalized autocalibrating partially parallel acquisition enabled the acquisition of isotropic high-spatial-resolution three-dimensional data sets for multiple stations. Two radiologists independently evaluated arterial image quality and presence of arterial stenoses. All examinations yielded good or excellent image quality. Interobserver agreement was excellent (kappa = 0.92; 95% confidence interval: 0.86, 0.96). Multistation whole-body MR angiography with high-acceleration parallel acquisition is feasible at 3.0 T. Further clinical studies combined with ongoing optimization of radiofrequency systems and coils seem warranted to advance the potential of this technology.
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Affiliation(s)
- Kambiz Nael
- Department of Radiological Sciences, David Geffen School of Medicine, University of California Los Angeles, 10945 Le Conte Ave, Suite 3371, Los Angeles, CA 90095-7206, USA.
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Tanaka YO, Ohtsuka S, Shindo M, Oyake Y, Minami M. Comparison of delayed myocardial enhancement in the early and late phase after contrast injection: is it possible to reduce the examination time for myocardial viability study? Magn Reson Imaging 2007; 25:232-7. [PMID: 17275619 DOI: 10.1016/j.mri.2006.09.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Accepted: 09/17/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVES We studied whether we can obtain a myocardial viability study immediately after contrast injection to reduce the whole cardiac MR examination time. MATERIALS AND METHODS We examined 36 patients with cardiovascular abnormality on comprehensive cardiac MRI. T1-weighted images with inversion recovery (IR) were obtained 5 min after stress perfusion with 0.05 mmol/kg of gadodiamide and 15 min after the resting perfusion with the same dose. (The latter images were obtained 25 min after the initial administration.) We evaluated the existence, the number of sectors, and the degree of enhancement at each time. The contrast ratio was also calculated. The number of the enhanced sectors and the contrast ratio were statistically compared using Student's t test. RESULTS All 17 cases of delayed myocardial enhancement at 25 min after contrast injection showed some enhancement at 5 min after contrast injection. However, the number of enhanced sectors was larger at 25 min after the initial injection in 11 cases, and it was statistically significant (P=.017). The degree of enhancement was stronger at 25 min in 14 cases. However, the contrast ratio at 5 and 25 min after contrast injection was not significantly different (P=.245). CONCLUSION Myocardial viability study immediately after contrast injection is too early to evaluate the extent of myocardial injury.
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Affiliation(s)
- Yumiko Oishi Tanaka
- Department of Radiology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan.
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Nael K, Ruehm SG, Michaely HJ, Saleh R, Lee M, Laub G, Finn JP. Multistation Whole-Body High-Spatial-Resolution MR Angiography Using a 32-Channel MR System. AJR Am J Roentgenol 2007; 188:529-39. [PMID: 17242265 DOI: 10.2214/ajr.05.2053] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE The objective of our study was to investigate a multistation whole-body MR angiography (MRA) protocol using a 32-channel MR system with multicoil technology in a population of patients with suspected peripheral vascular disease (PVD). SUBJECTS AND METHODS Fifty consecutive patients with suspected PVD (31 men, 19 women; age range, 46-91 years) underwent multistation whole-body contrast-enhanced MR angiography (CE-MRA) on a 32-channel 1.5-T MR system equipped with multicoil technology. A two-step contrast injection protocol was used: After the first injection, images of the most proximal station (station I, head and neck) were acquired, followed by the most distal station (station IV, calves). Images of the intermediate two stations (station II, chest and abdomen; station III, pelvis and thighs) were acquired during the second injection. Conventional catheter angiography was performed for symptomatic vascular regions in 30 patients. The image quality of the arterial segments and the presence and degree of the arterial stenosis were evaluated by two radiologists. The interobserver variability was calculated by kappa statistics, and comparative analysis between CE-MRA and catheter angiography was performed by means of the Spearman's rank correlation coefficient. RESULTS Most of the vascular segments (1,912/1,976 [97%]) were visualized on wholebody CE-MRA with diagnostic image quality. Significant arterial disease (> or = 50%) was detected in 167 (observer 1) and 177 (observer 2) segments with excellent interobserver agreement (kappa = 0.84). There was a significant correlation between CE-MRA and conventional angiography for the degree of stenosis (R = 0.92 and 0.89 for observers 1 and 2, respectively). The sensitivity and specificity of CE-MRA for the detection of arterial stenoses 50% or greater were 92% and 96% for observer 1 and 93% and 97% for observer 2, respectively, compared with those of conventional angiography. CONCLUSION Using a multichannel radiofrequency system with multicoil technology, the whole-body CE-MRA approach outlined in this article is able to provide high-spatial-resolution data sets with high diagnostic image quality for evaluation of arterial occlusive disease in most vascular territories.
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Affiliation(s)
- Kambiz Nael
- Department of Radiological Sciences, David Geffen School of Medicine, University of California at Los Angeles, 10945 Le Conte Ave., Ste. 3371, Los Angeles, CA 90095-7206, USA
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Goyen M. Gadofosveset: the first intravascular contrast agent EU-approved for use with magnetic resonance angiography. Future Cardiol 2007; 3:19-26. [PMID: 19804202 DOI: 10.2217/14796678.3.1.19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Gadofosveset is the first intravascular contrast agent approved for use with magnetic resonance angiography in the European Union. Gadofosveset reversibly binds to albumin, providing extended intravascular enhancement beyond that of existing extracellular magnetic resonance contrast agents. Prior to approval, gadofosveset underwent extensive testing to evaluate the safety and efficacy of the drug; the clinical trials program included blinded, placebo-controlled, dose-ranging, efficacy in a variety of vascular beds (areas of turbulent blood flow, renal and pedal), examination of potential drug interaction with warfarin and comparison with x-ray angiography. The clinical trials demonstrate that gadofosveset-enhanced magentic resonance angiography is: safe and well tolerated in patients with vascular disease; effective for the detection of vascular stenosis and aneurysms; significantly more accurate (both more sensitive and specific) than noncontrast magnetic resonance angiography for the diagnosis of vascular stenoses; and similar to conventional angiography for the overall characterization of vascular disease, without the need for catheterization.
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Affiliation(s)
- Mathias Goyen
- University Medical Center, Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
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Lin J, Chen B, Wang JH, Zeng MS, Wang YX. Whole-body three-dimensional contrast-enhanced magnetic resonance (MR) angiography with parallel imaging techniques on a multichannel MR system for the detection of various systemic arterial diseases. Heart Vessels 2006; 21:395-8. [PMID: 17143719 DOI: 10.1007/s00380-006-0918-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2005] [Accepted: 03/10/2006] [Indexed: 10/23/2022]
Abstract
Using a 1.5-T magnetic resonance (MR) imager equipped with 32 receiving channels and integrated parallel acquisition techniques, 37 patients underwent whole-body three-dimensional (3D) contrast-enhanced MR angiography (WB 3D CE MRA). The patients included had clinically documented or suspected peripheral arterial occlusive disease (PAOD, n = 19), Takayasu arteritis (n = 8), polyarteritis nodosa (n = 1), type-B dissection (n = 4), thoracic and/or abdominal aneurysm (n = 5). Sixty-eight surface coils were employed to encompass the whole body. Four 3D CE MRA stations were acquired successively through automatic table moving. The spatial resolution was 1.6 x 1.0 mm and slice thickness was 1.5 mm for all stations. A total scan range of 188 cm was acquired. Overall image quality of each arterial segment and venous overlay were assessed. The depiction of various systemic arterial diseases was evaluated and compared, in 20 patients, with other imaging modalities. This WB 3D CE MRA yielded a detailed display of the arterial system with an average MR room time of 17.4 min. The image quality was considered diagnostic in 99.3% of the arterial segments. In 7 of 19 patients with PAOD, WB MRA showed additional vascular narrowing apart from peripheral arterial disease. In nine patients with vasculitis, WB MRA depicted luminal irregularity, narrowing or occlusion, aneurysm, and collateral circulation involving multiple vascular segments. WB MRA also clearly revealed the severity and extent of dissection and aortic aneurysm. In 20 cases where additional imaging investigations have been carried out, the vascular pathologies demonstrated by WB MRA agree with these additional imaging investigations.
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Affiliation(s)
- Jiang Lin
- Department of Radiology, Shanghai Zhongshan Hospital, Shanghai Medical College, Fudan University, Shanghai 200032, China.
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Finn JP, Saleh R, Thesen S, Ruehm SG, Lee MH, Grinstead J, Child JS, Laub G. MR Imaging with Remote Control: Feasibility Study in Cardiovascular Disease. Radiology 2006; 241:528-37. [PMID: 17005775 DOI: 10.1148/radiol.2412051898] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The institutional review board approved this HIPAA-compliant study and waived informed consent. The purpose was to retrospectively evaluate remote control magnetic resonance (MR) imaging in complex cardiovascular procedures, whereby operational expertise was made available locally from a remote location. Thirty patients underwent cardiac (12 patients) and/or vascular (30 patients) 1.5-T MR imaging with a remote operator by using a personal computer. All patient studies were compared with 30 control studies obtained with conventional local imaging. Cardiac cine, myocardial delayed enhancement, and MR angiograms were assessed for overall image quality and motion artifact. MR angiograms were evaluated for vascular definition. Image quality was excellent in 90% (38 of 42) of remote images versus 60% (25 of 42) of control group images (P < .01). Scores for motion artifact were not significantly different (P = .11). Interactive MR imaging was successfully implemented with remote control in complex cardiovascular cases; diagnostic quality of images was superior to that of images obtained locally.
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Affiliation(s)
- J Paul Finn
- Department of Radiological Sciences, David Geffen School of Medicine, University of California at Los Angeles, Peter V. Ueberroth Bldg, Suite 3371, 10945 Le Conte Ave, Los Angeles, CA 90095-7206, USA.
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