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Gundogdu B, Pittman JM, Chatterjee A, Szasz T, Lee G, Giurcanu M, Medved M, Engelmann R, Guo X, Yousuf A, Antic T, Devaraj A, Fan X, Oto A, Karczmar GS. Directional and inter-acquisition variability in diffusion-weighted imaging and editing for restricted diffusion. Magn Reson Med 2022; 88:2298-2310. [PMID: 35861268 PMCID: PMC9545544 DOI: 10.1002/mrm.29385] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 06/15/2022] [Accepted: 06/21/2022] [Indexed: 11/23/2022]
Abstract
PURPOSE To evaluate and quantify inter-directional and inter-acquisition variation in diffusion-weighted imaging (DWI) and emphasize signals that report restricted diffusion to enhance cancer conspicuity, while reducing the effects of local microscopic motion and magnetic field fluctuations. METHODS Ten patients with biopsy-proven prostate cancer were studied under an Institutional Review Board-approved protocol. Individual acquisitions of DWI signal intensities were reconstructed to calculate inter-acquisition distributions and their statistics, which were compared for healthy versus cancer tissue. A method was proposed to detect and filter the acquisitions affected by motion-induced signal loss. First, signals that reflect restricted diffusion were separated from the acquisitions that suffer from signal loss, likely due to microscopic motion, by imposing a cutoff value. Furthermore, corrected apparent diffusion coefficient maps were calculated by employing a weighted sum of the multiple acquisitions, instead of conventional averaging. These weights were calculated by applying a soft-max function to the set of acquisitions per-voxel, making the analysis immune to acquisitions with significant signal loss, even if the number of such acquisitions is high. RESULTS Inter-acquisition variation is much larger than the Rician noise variance, local spatial variations, and the estimates of diffusion anisotropy based on the current data, as well as the published values of anisotropy. The proposed method increases the contrast for cancers and yields a sensitivity of98 . 8 % $$ 98.8\% $$ with a false positive rate of3 . 9 % $$ 3.9\% $$ . CONCLUSION Motion-induced signal loss makes conventional signal-averaging suboptimal and can obscure signals from areas with restricted diffusion. Filtering or weighting individual acquisitions prior to image analysis can overcome this problem.
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Affiliation(s)
| | - Jay M. Pittman
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | | | - Teodora Szasz
- Research Computing CenterUniversity of ChicagoChicagoIllinoisUSA
| | - Grace Lee
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Mihai Giurcanu
- Department of Public Health SciencesUniversity of ChicagoIllinoisUSA
| | - Milica Medved
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Roger Engelmann
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Xiaodong Guo
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Ambereen Yousuf
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Tatjana Antic
- Department of PathologyUniversity of ChicagoChicagoIllinoisUSA
| | - Ajit Devaraj
- Philips Research North AmericaCambridgeMassachusettsUSA
| | - Xiaobing Fan
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Aytekin Oto
- Department of RadiologyUniversity of ChicagoChicagoIllinoisUSA
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Cao X, Shi H, Dou WQ, Zhao XY, Zheng YX, Ge YP, Cheng HC, Geng DY, Wang JY. Can DKI-MRI predict recurrence and invasion of peritumoral zone of hepatocellular carcinoma after transcatheter arterial chemoembolization? World J Gastrointest Surg 2022; 14:1150-1160. [PMID: 36386402 PMCID: PMC9640335 DOI: 10.4240/wjgs.v14.i10.1150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/29/2022] [Accepted: 09/21/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Hepatocellular carcinoma (HCC) is a major cause of cancer-related mortality worldwide. Transcatheter arterial chemoembolization (TACE) has been performed as a palliative treatment for patients with HCC. However, HCC is easy to recur after TACE. Magnetic resonance imaging (MRI) has clinical potential in evaluating the TACE treatment effect for patients with liver cancer. However, traditional MRI has some limitations.
AIM To explore the clinical potential of diffusion kurtosis imaging (DKI) in predicting recurrence and cellular invasion of the peritumoral liver zone of HCC after TACE.
METHODS Seventy-six patients with 82 HCC nodules were recruited in this study and underwent DKI after TACE. According to pathological examinations or the overall modified response evaluation criteria in solid tumors (mRECIST) criterion, 48 and 34 nodules were divided into true progression and pseudo-progression groups, respectively. The TACE-treated area, peritumoral liver zone, and far-tumoral zone were evaluated on DKI-derived metric maps. Non-parametric U test and receiver operating characteristic curve (ROC) analysis were used to evaluate the prediction performance of each DKI metric between the two groups. The independent t-test was used to compare each DKI metric between the peritumoral and far-tumoral zones of the true progression group.
RESULTS DKI metrics, including mean diffusivity (MD), axial diffusivity (DA), radial diffusivity (DR), axial kurtosis (KA), and anisotropy fraction of kurtosis (Fak), showed statistically different values between the true progression and pseudo-progression groups (P < 0.05). Among these, MD, DA, and DR values were higher in pseudo-progression lesions than in true progression lesions, whereas KA and FAk values were higher in true progression lesions than in pseudo-progression lesions. Moreover, for the true progression group, the peritumoral zone showed significantly different DA, DR, KA, and FAk values from the far-tumoral zone. Furthermore, MD values of the liver parenchyma (peritumoral and far-tumoral zones) were significantly lower in the true progression group than in the pseudo-progression group (P < 0.05).
CONCLUSION DKI has been demonstrated with robust performance in predicting the therapeutic response of HCC to TACE. Moreover, DKI might reveal cellular invasion of the peritumoral zone by molecular diffusion-restricted change.
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Affiliation(s)
- Xin Cao
- Department of Medical Imaging, The First Affiliated Hospital of Shandong First Medical University & Shandong Province Qianfoshan Hospital, Jinan 250014, Shandong Province, China
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai 200040, China
- Center for Shanghai Intelligent Imaging for Critical Brain Diseases Engineering and Technology Research, Shanghai 200040, China
| | - Hao Shi
- Department of Medical Imaging, The First Affiliated Hospital of Shandong First Medical University & Shandong Province Qianfoshan Hospital, Jinan 250014, Shandong Province, China
| | | | - Xin-Yao Zhao
- Department of Radiology, Yantaishan Hospital, Yantai 264001, Shandong Province, China
| | - Ying-Xin Zheng
- Department of Magnetic Resonance Imaging, Zhangqiu District People's Hospital, Jinan 250200, Shandong Province, China
| | - Ya-Ping Ge
- Department of Medical Imaging, The First Affiliated Hospital of Shandong First Medical University & Shandong Province Qianfoshan Hospital, Jinan 250014, Shandong Province, China
| | - Hai-Chao Cheng
- Department of Medical Imaging, The First Affiliated Hospital of Shandong First Medical University & Shandong Province Qianfoshan Hospital, Jinan 250014, Shandong Province, China
| | - Dao-Ying Geng
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai 200040, China
- Center for Shanghai Intelligent Imaging for Critical Brain Diseases Engineering and Technology Research, Shanghai 200040, China
| | - Jun-Ying Wang
- Department of Medical Imaging, The First Affiliated Hospital of Shandong First Medical University & Shandong Province Qianfoshan Hospital, Jinan 250014, Shandong Province, China
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Diffusion kurtosis imaging in liver: a preliminary reproducibility study in healthy volunteers. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2020; 33:877-883. [PMID: 32377906 DOI: 10.1007/s10334-020-00846-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 04/07/2020] [Accepted: 04/16/2020] [Indexed: 12/29/2022]
Abstract
OBJECTIVES To systematically test the reproducibility of DKI technique in normal liver and report a complete set of DKI measurement data. MATERIALS AND METHODS Thirty-two healthy volunteers were examined with liver DKI twice on the GE 3.0 T MRI scanner and reviewed by three professional experts. DKI-derived parameters fractional anisotropy of kurtosis (FAk), mean diffusivity (Md), axial diffusivity (Da), radial diffusivity (Dr), mean kurtosis (Mk), axial kurtosis (Ka), and radial kurtosis (Kr) in eight segments divided by Couinaud octagonal method were collected. Inter-class correlation coefficient (ICC) was used to assess the agreement between three experts. For each expert, the reproducibility of twice scans was evaluated by Bland-Altman method. Multivariate analysis of variance was to explore the regional distribution characteristics of DKI-derived parameters, and showed with box-plot graph. RESULTS Using ICC analysis, except for FAk (ICC 0.312, 0.307), other DKI metric values showed high reproducibility (0.716 < ICC < 0.907) between three experts for each of two DKI measurements. With Bland-Altman method, liver segment 5 (S5) showed the best reproducibility between two DKI measurement, and the reproducibility of segment 4 (S4) was the worst. The reproducibility of the right lobe was significantly higher than the left lobe. The values of diffusion metrics (Md, Da, and Dr) and kurtosis metrics (Mk, Ka, and Kr) existed significantly difference between the right and left hepatic lobes. CONCLUSION DKI has shown excellent reproducibility in liver imaging. The range of values for multiple DKI parameters, derived from the normal liver, was reported, and may provide data reference for further clinical DKI applications. Additionally, DKI technique is a non-invasive method to reflect the perfusion or structural differences between the left and right hepatic lobes from the molecular level.
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Optimal strategy for measuring intraventricular temperature using acceleration motion compensation diffusion-weighted imaging. Radiol Phys Technol 2020; 13:136-143. [DOI: 10.1007/s12194-020-00560-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 03/03/2020] [Accepted: 03/05/2020] [Indexed: 10/24/2022]
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Phi van V, Reiner CS, Klarhoefer M, Ciritsis A, Eberhardt C, Wurnig MC, Rossi C. Diffusion tensor imaging of the abdominal organs: Influence of oriented intravoxel flow compartments. NMR IN BIOMEDICINE 2019; 32:e4159. [PMID: 31397037 DOI: 10.1002/nbm.4159] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 06/24/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
Water flow in partially oriented intravoxel compartments mimics an anisotropic fast-diffusion regime, which contributes to the signal attenuation in diffusion-weighted images. In the abdominal organs, this flow may reflect physiological fluid movements (eg, tubular urine flow in kidneys, or bile flow through the liver) and have a clinical relevance. This study investigated the influence of anisotropic intravoxel water flow on diffusion tensor imaging (DTI) of the abdominal organs. Diffusion-weighted images were acquired in five healthy volunteers using an EPI sequence with diffusion preparation (TR/TE: 1000 ms/71 ms; b-values: 0, 10, 20, 40, 70, 120, 250, 450, 700, 1000 s/mm2 ; 12 noncollinear diffusion-encoding directions). DTI of liver and kidneys was performed assuming (i) monoexponential decay of the diffusion-weighted signal, and (ii) accounting for potential anisotropy of the fast-diffusion compartments using a tensorial generalization of the IVIM model. Additionally, potential dependency of the metrics of the tensors from the anatomical location was evaluated. Significant differences in the metrics of the diffusion tensor (DT) were found in both liver and kidneys when comparing the two models. In both organs, the trace and the fractional anisotropy of the DT were significantly higher in the monoexponential model than when accounting for perfusion. The comparison of areas of the liver proximal to the hilum with distal regions and of renal cortex with the medulla also proved a location dependency of the size of the fast-diffusion compartments. Pseudo-diffusion correction in DTI enables the assessment of the solid parenchyma regardless of the organ perfusion or other pseudo-diffusive fluid movements. This may have a clinical relevance in the assessment of parenchymal pathologies (eg, liver fibrosis). The fast pseudo-diffusion components present a detectable anisotropy, which may reflect the hepatic microcirculation or other sources of mesoscopic fluid movement in the abdominal organs.
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Affiliation(s)
- Valerie Phi van
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Caecilia S Reiner
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland
| | | | - Alexander Ciritsis
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Christian Eberhardt
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland
| | - Moritz C Wurnig
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland
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Zhang Y, Peña-Nogales Ó, Holmes JH, Hernando D. Motion-robust and blood-suppressed M1-optimized diffusion MR imaging of the liver. Magn Reson Med 2019; 82:302-311. [PMID: 30859628 DOI: 10.1002/mrm.27735] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 02/10/2019] [Accepted: 02/20/2019] [Indexed: 12/11/2022]
Abstract
PURPOSE To develop motion-robust, blood-suppressed diffusion-weighted imaging (DWI) of the liver with optimized diffusion encoding waveforms and evaluate the accuracy and reproducibility of quantitative apparent diffusion coefficient (ADC) measurements. METHODS A novel approach for the design of diffusion weighting waveforms, termed M1-optimized diffusion imaging (MODI), is proposed. MODI includes an echo time-optimized motion-robust diffusion weighting gradient waveform design, with a small nonzero first-moment motion sensitivity (M1) value to enable blood signal suppression. Experiments were performed in eight healthy volunteers and five patient volunteers. In each case, DW images and ADC maps were compared between acquisitions using standard monopolar waveforms, motion moment-nulled (M1-nulled and M1-M2-nulled) waveforms, and the proposed MODI approach. RESULTS Healthy volunteer experiments using MODI showed no significant ADC bias in the left lobe relative to the right lobe (p < .05) demonstrating robustness to cardiac motion, and no significant ADC bias with respect to monopolar-based ADC measured in the right lobe (p < .05), demonstrating blood signal suppression. In contrast, monopolar-based ADC showed significant bias in the left lobe relative to the right lobe (p < .01) due to its sensitivity to motion, and both M1-nulled and M1-M2-nulled-based ADC showed significant bias (p < .01) due to the lack of blood suppression. Preliminary patient results also suggest MODI may enable improved visualization and quantitative assessment of lesions throughout the entire liver. CONCLUSIONS This novel method for diffusion gradient waveform design enables DWI of the liver with high robustness to motion and suppression of blood signals, overcoming the limitations of conventional monopolar waveforms and moment-nulled waveforms, respectively.
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Affiliation(s)
- Yuxin Zhang
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Óscar Peña-Nogales
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin.,Laboratorio de Procesado de Imagen, Universidad de Valladolid, Valladolid, Spain
| | - James H Holmes
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Diego Hernando
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
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Ichikawa S, Motosugi U, Tamada D, Wakayama T, Sato K, Funayama S, Onishi H. Improving the Quality of Diffusion-weighted Imaging of the Left Hepatic Lobe Using Weighted Averaging of Signals from Multiple Excitations. Magn Reson Med Sci 2018; 18:225-232. [PMID: 30555108 PMCID: PMC6630049 DOI: 10.2463/mrms.mp.2018-0085] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Background: Diffusion-weighted imaging (DWI) is useful for detecting and characterizing liver lesions but is sensitive to organ motion artifact, especially in the left lobe. Purpose: To assess the signal intensity (SI) loss in the left hepatic lobe on DWI depending on motion-proving gradient (MPG) pulse direction (preliminary study) and to evaluate the usefulness of modified signal averaging to reduce the SI loss on DWI (application study). Methods: About 48 (preliminary) and 35 (application) patients were included. In the preliminary study, DWI with four different MPG directions, only a single MPG pulse direction (x-, y-, or z-axis) and all three directions combined (standard DWI), were reconstructed from the original data. In the application study, we examined the usefulness of the weighted averaging number of excitations (wNEX) method, in which a larger weighting factor is applied to the higher signal in pixel-by-pixel NEX signal averaging by comparing four reconstruction methods. We assumed that true signals would be the same in both lobes. The SI and apparent diffusion coefficient (ADC) ratios for the left versus right lobe were calculated by dividing the SI/ADC of the right lobe by that of the left lobe. Results: In the preliminary study, the SI ratio was significantly lower on DWI using only the x-axis but was significantly higher on DWI using only the z-axis (both P < 0.0001) when compared with standard DWI. In the application study, the SI (mean, 1.15–1.17) and ADC (0.90–0.92) ratios on DWI with wNEX were closer to 1.0 than those on standard DWI (SI ratio, 1.32–1.38; ADC ratio 0.80–0.81); the differences were significant (all P < 0.0001). Conclusion: The MPG pulse along the z-axis caused signal loss in the left hepatic lobe. The wNEX reconstruction method effectively reduced signal loss in the left lobe on DWI.
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Affiliation(s)
| | | | - Daiki Tamada
- Department of Radiology, University of Yamanashi
| | | | - Kazuyuki Sato
- Division of Radiology, University of Yamanashi Hospital
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Evaluation and Minimization of the Pseudohepatic Anisotropy Artifact in Liver Intravoxel Incoherent Motion. J Comput Assist Tomogr 2017; 41:679-687. [PMID: 28708735 DOI: 10.1097/rct.0000000000000604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
PURPOSE The aim of this study was to evaluate the effect of the pseudohepatic anisotropy artifact on liver intravoxel incoherent motion (IVIM) metrics and whether the use of multiple gradient directions in the IVIM acquisition minimizes the artifact. MATERIALS AND METHODS Multiple breath-holding and forced shallow free-breathing IVIM scans were performed on 8 healthy volunteers using 1 and 6 gradient directions. Cluster analysis was carried out to separate motion-contaminated parenchyma from liver parenchyma and vessels. Nonlinear motion analysis was also performed to look for a possible link between IVIM metrics and nonlinear liver motion. RESULTS On the basis of the resulted clusters, motion-contaminated parenchyma is often noted in the left liver lobe, where the prominent pseudohepatic artifact has previously been identified. A significant reduction in outliers was obtained with the acquisition of 6 noncoplanar gradient directions and when using forced shallow free-breathing. CONCLUSION The pseudohepatic anisotropy artifact can be minimized when using multiple diffusion-encoding gradient directions and forced free-breathing during IVIM acquisition.
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Evaluating histologic differentiation of hepatitis B virus-related hepatocellular carcinoma using intravoxel incoherent motion and AFP levels alone and in combination. Abdom Radiol (NY) 2017; 42:2079-2088. [PMID: 28337521 DOI: 10.1007/s00261-017-1107-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE To evaluate histologic differentiation of hepatitis B virus (HBV)-related hepatocellular carcinomas (HCCs) using apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM)-derived metrics and to compare findings with alpha-fetoprotein (AFP) levels alone and in combination. MATERIALS AND METHOD One hundred and six chronic HBV-related HCC patients who underwent IVIM diffusion-weighted magnetic resonance imaging with eleven b values were enrolled. Mean ADC, diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) values were determined for all detected lesions. The metrics and AFP levels of different histologically differentiated groups were compared. Spearman's rank correlation was used to assess the statistical dependence among the histologically differentiated HCCs. Receiver operating characteristic (ROC) analysis was performed to evaluate diagnostic performance of these metrics and AFP levels alone and in combination. RESULTS ADC, D, and f values and AFP levels were significantly different among well-, moderately, and poorly differentiated HCCs. The four metrics were significantly correlated with histologic differentiation. The area under the ROC curve (AUC-ROC) of ADC, D, f, and AFP for diagnosing well-differentiated HCCs was 0.903, 0.84, 0.782, and 0.806, respectively, and the AUC-ROC of above metrics for diagnosing poorly differentiated HCCs was 0.787, 0.726, 0.624, and 0.633, respectively. The combination of ADC and AFP provided an AUC-ROC of 0.945 for well-differentiated HCC. However, this did not provide better performance for diagnosing poorly differentiated HCC. CONCLUSION ADC, IVIM metrics, and AFP levels may be useful for evaluating histologic differentiation of HBV-related HCCs, and the combination of ADC and AFP provides better diagnostic performance for well-differentiated HCC.
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Lanzman RS, Wittsack HJ. Diffusion tensor imaging in abdominal organs. NMR IN BIOMEDICINE 2017; 30:e3434. [PMID: 26556181 DOI: 10.1002/nbm.3434] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 09/18/2015] [Accepted: 09/20/2015] [Indexed: 06/05/2023]
Abstract
Initially, diffusion tensor imaging (DTI) was mainly applied in studies of the human brain to analyse white matter tracts. As DTI is outstanding for the analysis of tissue´s microstructure, the interest in DTI for the assessment of abdominal tissues has increased continuously in recent years. Tissue characteristics of abdominal organs differ substantially from those of the human brain. Further peculiarities such as respiratory motion and heterogenic tissue composition lead to difficult conditions that have to be overcome in DTI measurements. Thus MR measurement parameters have to be adapted for DTI in abdominal organs. This review article provides information on the technical background of DTI with a focus on abdominal imaging, as well as an overview of clinical studies and application of DTI in different abdominal regions. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Rotem Shlomo Lanzman
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University of Dusseldorf, Dusseldorf, Germany
| | - Hans-Jörg Wittsack
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University of Dusseldorf, Dusseldorf, Germany
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Saito K, Tajima Y, Harada TL. Diffusion-weighted imaging of the liver: Current applications. World J Radiol 2016; 8:857-867. [PMID: 27928467 PMCID: PMC5120245 DOI: 10.4329/wjr.v8.i11.857] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 08/10/2016] [Accepted: 10/24/2016] [Indexed: 02/06/2023] Open
Abstract
Diffusion-weighted imaging (DWI) of the liver can be performed using most commercially available machines and is currently accepted in routine sequence. This sequence has some potential as an imaging biomarker for fibrosis, tumor detection/characterization, and following/predicting therapy. To improve reliability including accuracy and reproducibility, researchers have validated this new technique in terms of image acquisition, data sampling, and analysis. The added value of DWI in contrast-enhanced magnetic resonance imaging was established in the detection of malignant liver lesions. However, some limitations remain in terms of lesion characterization and fibrosis detection. Furthermore, the methodologies of image acquisition and data analysis have been inconsistent. Therefore, researchers should make every effort to not only improve accuracy and reproducibility but also standardize imaging parameters.
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Cui L, Yin JB, Hu CH, Gong SC, Xu JF, Yang JS. Inter- and intraobserver agreement of ADC measurements of lung cancer in free breathing, breath-hold and respiratory triggered diffusion-weighted MRI. Clin Imaging 2016; 40:892-6. [PMID: 27183136 DOI: 10.1016/j.clinimag.2016.04.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 03/28/2016] [Accepted: 04/08/2016] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To prospectively evaluate the inter- and intraobserver agreement of apparent diffusion coefficient (ADC) measurements in free breathing, breath-hold, and respiratory triggered diffusion-weighted imaging (DWI) of lung cancer. METHODS Twenty-two patients with lung cancer (tumor size >2cm) underwent DWIs (3.0T) in three imaging methods. Lesion ADCs were measured twice by both of the two independent observers and compared. RESULTS No statistical significance was found among methods, though respiratory-triggered DWI tended to have higher ADCs than breath-hold DWI. Great inter- and intraobserver agreement was shown. CONCLUSION ADCs had good inter- and intraobserver agreement in all three DWI methods.
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Affiliation(s)
- Lei Cui
- Department of Radiology, First Affiliated Hospital of Soochow University, 188 Shixi Street, Suzhou, Jiangsu, PR China, 215006; Department of Radiology, Second Affiliated Hospital of Nantong University, 6 Hai'er Road, Chongchuan District, Nantong, Jiangsu, PR China, 226001
| | - Jian-Bing Yin
- Department of Radiology, Second Affiliated Hospital of Nantong University, 6 Hai'er Road, Chongchuan District, Nantong, Jiangsu, PR China, 226001
| | - Chun-Hong Hu
- Department of Radiology, First Affiliated Hospital of Soochow University, 188 Shixi Street, Suzhou, Jiangsu, PR China, 215006.
| | - Shen-Chu Gong
- Department of Radiology, Second Affiliated Hospital of Nantong University, 6 Hai'er Road, Chongchuan District, Nantong, Jiangsu, PR China, 226001.
| | - Jun-Feng Xu
- Department of Radiology, Second Affiliated Hospital of Nantong University, 6 Hai'er Road, Chongchuan District, Nantong, Jiangsu, PR China, 226001
| | - Ju-Shun Yang
- Department of Radiology, Second Affiliated Hospital of Nantong University, 6 Hai'er Road, Chongchuan District, Nantong, Jiangsu, PR China, 226001
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Taron J, Martirosian P, Erb M, Kuestner T, Schwenzer NF, Schmidt H, Honndorf VS, Weiβ J, Notohamiprodjo M, Nikolaou K, Schraml C. Simultaneous multislice diffusion-weighted MRI of the liver: Analysis of different breathing schemes in comparison to standard sequences. J Magn Reson Imaging 2016; 44:865-79. [PMID: 26919580 DOI: 10.1002/jmri.25204] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To systematically evaluate image characteristics of simultaneous-multislice (SMS)-accelerated diffusion-weighted imaging (DWI) of the liver using different breathing schemes in comparison to standard sequences. MATERIALS AND METHODS DWI of the liver was performed in 10 healthy volunteers and 12 patients at 1.5T using an SMS-accelerated echo planar imaging sequence performed with respiratory-triggering and free breathing (SMS-RT, SMS-FB). Standard DWI sequences served as reference (STD-RT, STD-FB). Reduction of scan time by SMS-acceleration was measured. Image characteristics of SMS-DWI and STD-DWI with both breathing schemes were analyzed quantitatively (apparent diffusion coefficient [ADC], signal-to-noise ratio [SNR]) and qualitatively (5-point Likert scale, 5 = excellent). Qualitative and quantitative parameters were compared using Friedman test and Dunn-Bonferroni post-hoc method with P-values < 0.05 considered statistically significant. RESULTS SMS-DWI provided diagnostic image quality in volunteers and patients both with RT and FB with a reduction of scan time of 70% (0:56 vs. 3:20 min in FB). Overall image quality did not significantly differ between FB and RT acquisition in both STD and SMS sequences (median STD-RT 5.0, STD-FB 4.5, SMS-RT: 4.75; SMS-FB: 4.5; P = 0.294). SNR in the right hepatic lobe was comparable between the four tested sequences. ADC values were significantly lower in SMS-DWI compared to STD-DWI irrespective of the breathing scheme (1.2 ± 0.2 × 10(-3) mm(2) /s vs. 1.0 ± 0.2 × 10(-3) mm(2) /s; P < 0.001). CONCLUSION SMS-acceleration provides considerable scan time reduction for hepatic DWI with equivalent image quality compared to the STD technique both using RT and FB. Discrepancies in ADC between STD-DWI and SMS-DWI need to be considered when transferring the SMS technique to clinical routine reading. J. MAGN. RESON. IMAGING 2016;44:865-879.
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Affiliation(s)
- Jana Taron
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Petros Martirosian
- Section on Experimental Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Michael Erb
- Department of Biomedical Magnetic Resonance, University Hospital of Tuebingen, Tuebingen, Germany
| | - Thomas Kuestner
- Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany
| | - Nina F Schwenzer
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Holger Schmidt
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Valerie S Honndorf
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Jakob Weiβ
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Mike Notohamiprodjo
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Konstantin Nikolaou
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Christina Schraml
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany.
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14
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Ni P, Lin Y, Zhong Q, Chen Z, Sandrasegaran K, Lin C. Technical advancements and protocol optimization of diffusion-weighted imaging (DWI) in liver. Abdom Radiol (NY) 2016; 41:189-202. [PMID: 26830624 DOI: 10.1007/s00261-015-0602-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An area of rapid advancement in abdominal MRI is diffusion-weighted imaging (DWI). By measuring diffusion properties of water molecules, DWI is capable of non-invasively probing tissue properties and physiology at cellular and macromolecular level. The integration of DWI as part of abdominal MRI exam allows better lesion characterization and therefore more accurate initial diagnosis and treatment monitoring. One of the most technical challenging, but also most useful abdominal DWI applications is in liver and therefore requires special attention and careful optimization. In this article, the latest technical developments of DWI and its liver applications are reviewed with the explanations of the technical principles, recommendations of the imaging parameters, and examples of clinical applications. More advanced DWI techniques, including Intra-Voxel Incoherent Motion (IVIM) diffusion imaging, anomalous diffusion imaging, and Diffusion Kurtosis Imaging (DKI) are discussed.
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Affiliation(s)
- Ping Ni
- Department of Medical Imaging, Fuzhou General Hospital, Fuzhou, Fujian, China
| | - Yuning Lin
- Department of Medical Imaging, Fuzhou General Hospital, Fuzhou, Fujian, China
| | - Qun Zhong
- Department of Medical Imaging, Fuzhou General Hospital, Fuzhou, Fujian, China
| | - Ziqian Chen
- Department of Medical Imaging, Fuzhou General Hospital, Fuzhou, Fujian, China
| | - Kumar Sandrasegaran
- Department of Radiology and Imaging Science, Indiana University School of Medicine, 950 West Walnut St. R2 E124, Indianapolis, IN, 46202, USA
| | - Chen Lin
- Department of Radiology and Imaging Science, Indiana University School of Medicine, 950 West Walnut St. R2 E124, Indianapolis, IN, 46202, USA.
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15
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Metens T, Absil J, Denolin V, Bali MA, Matos C. Liver apparent diffusion coefficient repeatability with individually predetermined optimal cardiac timing and artifact elimination by signal filtering. J Magn Reson Imaging 2015; 43:1100-10. [DOI: 10.1002/jmri.25089] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 10/26/2015] [Indexed: 12/11/2022] Open
Affiliation(s)
- Thierry Metens
- MRI Clinics; Department of Radiology; Hopital Erasme; Universite Libre de Bruxelles; Bruxelles Belgium
| | - Julie Absil
- MRI Clinics; Department of Radiology; Hopital Erasme; Universite Libre de Bruxelles; Bruxelles Belgium
| | | | - Maria Antonietta Bali
- MRI Clinics; Department of Radiology; Hopital Erasme; Universite Libre de Bruxelles; Bruxelles Belgium
| | - Celso Matos
- MRI Clinics; Department of Radiology; Hopital Erasme; Universite Libre de Bruxelles; Bruxelles Belgium
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16
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Jang M, Kim SM, Yun BL, Ahn HS, Kim SY, Kang E, Kim SW. Reproducibility of Apparent Diffusion Coefficient Measurements in Malignant Breast Masses. J Korean Med Sci 2015; 30:1689-97. [PMID: 26539016 PMCID: PMC4630488 DOI: 10.3346/jkms.2015.30.11.1689] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 07/30/2015] [Indexed: 01/26/2023] Open
Abstract
This study aimed to evaluate the reproducibility of apparent diffusion coefficient (ADC) measurements in malignant breast masses, and to determine the influence of mammographic parenchymal density on this reproducibility. Sixty-six patients with magnetic resonance findings of the mass were included. Two breast radiologists measured the ADC of the malignant breast mass and the same area on the contralateral normal breast in each patient twice. The effects of mammographic parenchymal density, histology, and lesion size on reproducibility were also assessed. There was no significant difference in the mean ADC between repeated measurements in malignant breast masses and normal breast tissue. The overall reproducibility of ADC measurements was good in both. The 95% limits of agreement for repeated ADCs were approximately 30.2%-33.4% of the mean. ADC measurements in malignant breast masses were highly reproducible irrespective of mass size, histologic subtype, or coexistence of microcalcifications; however, the measurements tended to be less reproducible in malignant breast masses with extremely dense parenchymal backgrounds. ADC measurements in malignant breast masses are highly reproducible; however, mammographic parenchymal density can potentially influence this reproducibility.
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Affiliation(s)
- Mijung Jang
- Department of Radiology, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Sun Mi Kim
- Department of Radiology, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Bo La Yun
- Department of Radiology, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hye Shin Ahn
- Department of Radiology, Chung-Ang University Hospital, Seoul, Korea
| | - Soo Yeon Kim
- Department of Radiology, Hanyang University Guri Hospital, Guri, Korea
| | - Eunyoung Kang
- Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Sung-Won Kim
- Department of Surgery, Breast Care Center, Daerim St. Mary's Hospital, Seoul, Korea
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17
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Simultaneous Multislice Accelerated Free-Breathing Diffusion-Weighted Imaging of the Liver at 3T. ACTA ACUST UNITED AC 2015; 40:2323-30. [DOI: 10.1007/s00261-015-0447-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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18
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Palmucci S, Cappello G, Attinà G, Fuccio Sanzà G, Foti PV, Ettorre GC, Milone P. Diffusion-weighted MRI for the assessment of liver fibrosis: principles and applications. BIOMED RESEARCH INTERNATIONAL 2015; 2015:874201. [PMID: 25866819 PMCID: PMC4383436 DOI: 10.1155/2015/874201] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 12/14/2014] [Accepted: 01/01/2015] [Indexed: 12/19/2022]
Abstract
The importance of an early identification of hepatic fibrosis has been emphasized, in order to start therapy and obtain fibrosis regression. Biopsy is the gold-standard method for the assessment of liver fibrosis in chronic liver diseases, but it is limited by complications, interobserver variability, and sampling errors. Several noninvasive methods have been recently introduced into clinical routine, in order to detect liver fibrosis early. One of the most diffuse approaches is represented by diffusion-weighted liver MRI. In this review, the main technical principles are briefly reported in order to explain the rationale for clinical applications. In addition, roles of apparent diffusion coefficient, intravoxel incoherent motion, and relative apparent diffusion coefficient are also reported, showing their advantages and limits.
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Affiliation(s)
- Stefano Palmucci
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
| | - Giuseppina Cappello
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
| | - Giancarlo Attinà
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
| | - Giovanni Fuccio Sanzà
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
| | - Pietro Valerio Foti
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
| | - Giovanni Carlo Ettorre
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
| | - Pietro Milone
- Radiodiagnostic and Radiotherapy Unit, University Hospital “Policlinico-Vittorio Emanuele”, 95123 Catania, Italy
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19
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Lee Y, Lee SS, Kim N, Kim E, Kim YJ, Yun SC, Kühn B, Kim IS, Park SH, Kim SY, Lee MG. Intravoxel Incoherent Motion Diffusion-weighted MR Imaging of the Liver: Effect of Triggering Methods on Regional Variability and Measurement Repeatability of Quantitative Parameters. Radiology 2015; 274:405-15. [DOI: 10.1148/radiol.14140759] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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20
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Barral M, Taouli B, Guiu B, Koh DM, Luciani A, Manfredi R, Vilgrain V, Hoeffel C, Kanematsu M, Soyer P. Diffusion-weighted MR Imaging of the Pancreas: Current Status and Recommendations. Radiology 2015; 274:45-63. [DOI: 10.1148/radiol.14130778] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Magnetic resonance imaging of the liver: apparent diffusion coefficients from multiexponential analysis of b values greater than 50 s/mm2 do not respond to caloric intake despite increased portal-venous blood flow. Invest Radiol 2014; 49:138-46. [PMID: 24169068 DOI: 10.1097/rli.0000000000000005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE The purpose of this study was to measure potential changes of the apparent diffusion coefficient (ADC) in diffusion-weighted imaging of the liver before and after caloric challenge in correlation to the induced changes in portal vein flow. MATERIALS AND METHODS The study was approved by the local ethics committee. Each of 10 healthy volunteers underwent 4 measurements in a 1.5-T whole-body magnetic resonance scanner on 2 different days: a first scan after fasting for at least 8 hours and a second scan 30 minutes after intake of a standardized caloric either a protein- or carbohydrate-rich meal. Diffusion-weighted spin-echo echo-planar magnetic resonance images were acquired at b values of 0, 50, 150, 250, 500, 750, and 1000 s/mm. In addition, portal vein flow was quantified with 2-dimensional phase-contrast imaging (velocity encoding parallel to flow direction, 60 cm/s). Mean ADC values for regions of interest in 3 different slices were measured from b50 to b250 and from b500 to b1000 images. RESULTS Carbohydrate- and protein-rich food intake both resulted in a substantial increase in the portal vein flow (fasting state, 638.6 ± 202.3 mL/min; after protein intake, 1322 ± 266.8; after carbohydrate intake, 1767 ± 421.6). The signal decay with increasingly strong diffusion weighting (b values from 0 to 1000 s/mm2) exhibited a triexponential characteristic, implying fast, intermediate, and slow-moving water-molecule proton-spin ensembles in the liver parenchyma. Mean ADC for high b values (b500-b1000) after fasting was 0.93 ± 0.09 × 10 mm/s; that after protein intake, 0.93 ± 0.11 × 10; and that after carbohydrate intake, 0.93 ± 0.08 × 10. For intermediate b values (b50-b250), the signal-decay constants were 1.27 ± 0.14 × 10 mm/s, 1.28 ± 0.15 × 10, and 1.31 ± 0.09 × 10, respectively. There was no statistically significant difference between fasting and caloric challenge. CONCLUSIONS The postprandial increase in portal vein flow is not accompanied by a change of liver parenchymal ADC values. In clinical diffusion imaging, patients may be scanned without prescan food-intake preparations. To minimize interference of perfusion effects, liver-tissue molecular water diffusion should be quantified using high b values (≥500 s/mm) only.
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22
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The effect of respiratory and cardiac motion in liver diffusion tensor imaging (DTI). J Comput Assist Tomogr 2014; 38:352-9. [PMID: 24681854 DOI: 10.1097/rct.0000000000000064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the effect of respiratory and cardiac motion on diffusion tensor imaging (DTI) metrics in healthy human liver. METHODS Fifteen healthy subjects, participating in either part of this study, were scanned using a 1.5-T magnetic resonance imaging (MRI) device. Coronal liver DTI (6 diffusion-encoding directions; b, 300 mm/s) during breath holding was compared to free breathing. Cardiac motion effects were evaluated by comparing breath-held DTI scans acquired during both diastole and systole. RESULTS Free breathing resulted in a significantly increased mean diffusivity (P < 0.05), λ1 (P < 0.01), λ2 (P < 0.05), and λ3 (P < 0.01) compared to breath holding. During systole significant increases in fractional anisotropy (P < 0.05), mean diffusivity (P < 0.05), and λ1 (P < 0.05), compared to systole, were found in the left lobe. The right lobe, which is less affected by cardiac motion, showed no significant change in DTI metrics over the cardiac cycle. CONCLUSIONS Respiratory and cardiac motion tends to increase liver DTI metrics.
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23
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Chen X, Qin L, Pan D, Huang Y, Yan L, Wang G, Liu Y, Liang C, Liu Z. Liver diffusion-weighted MR imaging: reproducibility comparison of ADC measurements obtained with multiple breath-hold, free-breathing, respiratory-triggered, and navigator-triggered techniques. Radiology 2014; 271:113-25. [PMID: 24475860 DOI: 10.1148/radiol.13131572] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE To prospectively compare the reproducibility of normal liver apparent diffusion coefficient (ADC) measurements by using different respiratory motion compensation techniques with multiple breath-hold (MBH), free-breathing (FB), respiratory-triggered (RT), and navigator-triggered (NT) diffusion-weighted (DW) imaging and to compare the ADCs at different liver anatomic locations. MATERIALS AND METHODS The study protocol was approved by the institutional review board, and written informed consent was obtained from each participant. Thirty-nine volunteers underwent liver DW imaging twice. Imaging was performed with a 1.5-T MR imager with MBH, FB, RT, and NT techniques (b = 0, 100, and 500 sec/mm(2)). Three representative sections--superior, central, and inferior--were selected on left and right liver lobes, respectively. On each selected section, three regions of interest were drawn, and ADCs were measured. Analysis of variance was used to assess ADCs among the four techniques and various anatomic locations. Reproducibility of ADCs was assessed with the Bland-Altman method. RESULTS ADCs obtained with MBH (range: right lobe, [1.641-1.662] × 10(-3)mm(2)/sec; left lobe, [2.034-2.054] ×10(-3)mm(2)/sec) were higher than those obtained with FB (right, [1.349-1.391] ×10(-3)mm(2)/sec; left, [1.630-1.700] ×10(-3)mm(2)/sec), RT (right, [1.439-1.455] ×10(-3)mm(2)/sec; left, [1.720-1.755] ×10(-3)mm(2)/sec), or NT (right, [1.387-1.400] ×10(-3)mm(2)/sec; left, [1.661-1.736] ×10(-3)mm(2)/sec) techniques (P < .001); however, no significant difference was observed between ADCs obtained with FB, RT, and NT techniques (P = .130 to P >.99). ADCs showed a trend to decrease moving from left to right. Reproducibility in the left liver lobe was inferior to that in the right, and the central middle segment in the right lobe had the most reproducible ADC. Statistical differences in ADCs were observed in the left-right direction in the right lobe (P < .001), but they were not observed in the superior-inferior direction (P = .144-.450). However, in the left liver lobe, statistical differences existed in both directions (P = .001 to P = .016 in the left-right direction, P < .001 in the superior-inferior direction). CONCLUSION Both anatomic location and DW imaging technique influence liver ADC measurements and their reproducibility. FB DW imaging is recommended for liver DW imaging because of its good reproducibility and shorter acquisition time compared with that of MBH, RT, and NT techniques.
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Affiliation(s)
- Xin Chen
- From the Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, China (X.C., D.P., Y.H., L.Y., G.W., Y.L., C.L., Z.L.); Graduate College, Southern Medical University, Guangzhou, China (X.C., D.P.); and Department of Radiology, Dana-Farber Cancer Institute, Boston, Mass (L.Q.)
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Galea N, Cantisani V, Taouli B. Liver lesion detection and characterization: role of diffusion-weighted imaging. J Magn Reson Imaging 2014; 37:1260-76. [PMID: 23712841 DOI: 10.1002/jmri.23947] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 10/11/2012] [Indexed: 12/11/2022] Open
Abstract
Diffusion-weighted imaging (DWI) plays an emerging role for the assessment of focal and diffuse liver diseases. This growing interest is due to that fact that DWI is a noncontrast technique with inherent high contrast resolution, with promising results for detection and characterization of focal liver lesions. Recent advances in diffusion image quality have also added interest to this technique in the abdomen. The purpose of this review is to describe the current clinical roles of DWI for the detection and characterization of focal liver lesions, and to review pitfalls, limitations, and future directions of DWI for assessment of focal liver disease.
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Affiliation(s)
- Nicola Galea
- Sapienza University of Rome, Department of Radiological Sciences, Rome, Italy
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Quantitative liver ADC measurements using diffusion-weighted MRI at 3 Tesla: evaluation of reproducibility and perfusion dependence using different techniques for respiratory compensation. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2013; 26:431-42. [PMID: 23483359 DOI: 10.1007/s10334-013-0375-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Revised: 02/22/2013] [Accepted: 02/23/2013] [Indexed: 12/13/2022]
Abstract
OBJECT Diffusion weighted imaging (DWI) of the liver suffers from low signal to noise making 3 Tesla (3 T) an attractive option, but 3 T data is scarce. It was the aim to study the influence of different b values and respiratory compensation methods (RCM) on the apparent diffusion coefficient (ADC) level and on ADC reproducibility at 3 T. MATERIALS AND METHODS Ten healthy volunteers and 12 patients with malignant liver lesions underwent repeated (2-22 days) breathhold, free-breathing and respiratory triggered DWI at 3 T using b values between 0 and 1,000 s/mm(2). RESULTS The ADCs changed up to 150% in healthy livers and up to 48% in malignant lesions depending on b value combinations. Best ADC reproducibility in healthy livers were obtained with respiratory triggering (95% limits of agreement: ±0.12) and free-breathing (±0.14). In malignant lesions equivalent reproducibility was obtained with less RCM dependence. The use of a lower maximum b value (b = 500) decreased reproducibility (±0.14 to ±0.32) in both normal liver and malignant lesions. CONCLUSION Large differences in absolute ADC values and reproducibility caused by varying combinations of clinically realistic b values were demonstrated. Different RCMs caused smaller differences. Lowering maximum b value to 500 increased limits of agreement up to a factor of two. Serial ADC changes larger than approximately 15% can be detected confidently on an individual basis in both malignant lesions and normal liver parenchyma at 3 T using appropriate b values and respiratory compensation.
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Murphy P, Wolfson T, Gamst A, Sirlin C, Bydder M. Error model for reduction of cardiac and respiratory motion effects in quantitative liver DW-MRI. Magn Reson Med 2012; 70:1460-9. [PMID: 23280855 DOI: 10.1002/mrm.24563] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Revised: 09/23/2012] [Accepted: 10/31/2012] [Indexed: 01/26/2023]
Abstract
Diffusion-weighted images of the liver exhibit signal dropout from cardiac and respiratory motion, particularly in the left lobe. These artifacts cause bias and variance in derived parameters that quantify intravoxel incoherent motion. Many models of diffusion have been proposed, but few separate attenuation from diffusion or perfusion from that of bulk motion. The error model proposed here (Beta*LogNormal) is intended to accomplish that separation by modeling stochastic attenuation from bulk motion as multiplication by a Beta-distributed random variate. Maximum likelihood estimation with this error model can be used to derive intravoxel incoherent motion parameters separate from signal dropout, and does not require a priori specification of parameters to do so. Liver intravoxel incoherent motion parameters were derived for six healthy subjects under this error model and compared with least-squares estimates. Least-squares estimates exhibited bias due to cardiac and respiratory gating and due to location within the liver. Bias from these factors was significantly reduced under the Beta*LogNormal model, as was within-organ parameter variance. Similar effects were appreciable in diffusivity maps in two patients with focal liver lesions. These results suggest that, relative to least-squares estimation, the Beta*LogNormal model accomplishes the intended reduction of bias and variance from bulk motion in liver diffusion imaging.
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Affiliation(s)
- Paul Murphy
- Department of Radiology, University of California, San Diego, California
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Nam SJ, Park KY, Yu JS, Chung JJ, Kim JH, Kim KW. Hepatic cavernous hemangiomas: relationship between speed of intratumoral enhancement during dynamic MRI and apparent diffusion coefficient on diffusion-weighted imaging. Korean J Radiol 2012; 13:728-35. [PMID: 23118571 PMCID: PMC3484293 DOI: 10.3348/kjr.2012.13.6.728] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 05/08/2012] [Indexed: 02/06/2023] Open
Abstract
Objective To investigate the relationships between the apparent diffusion coefficients (ADCs) on diffusion-weighted imaging (DWI) and the speed of contrast-enhancement in hepatic hemangiomas. Materials and Methods Sixty-nine hepatic hemangiomas (≥ 1 cm) were evaluated with DWI, by using multiple b values (b = 50, 400, 800 s/mm2), followed by a gadolinium-enhanced dynamic MRI. The lesions were classified into three groups, according to the speed of contrast-enhancement on the portal phase. ADCs were measured on the ADC map automatically, and were calculated by using the two different b values (mADC50-400 with b values = 50 and 400; mADC400-800 with b values = 400 and 800 s/mm2). Results The mean ADCs (× 10-3 mm2/s) were significantly higher in the rapid group (1.9 ± 0.44) than in the intermediate (1.7 ± 0.35, p = 0.046) or the slow groups (1.4 ± 0.34, p = 0.002). There were significant differences between the rapid and the slow groups in mADC50-400 (2.12 vs. 1.48; p = 0.008) and mADC400-800 (1.68 vs. 1.22, p = 0.010), and between the rapid and the intermediate groups in mADC50-400 (2.12 vs. 1.79, p = 0.049). Comparing mADC50-400 with mADC400-800, there was a significant difference only in the rapid group (p = 0.001). Conclusion Higher ADCs of rapidly-enhancing hemangiomas may be related to richer intralesional vascular perfusion. Also, the restricted diffusion may be attributed to the difference of structural characteristics of hemangioma.
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Affiliation(s)
- Se Jin Nam
- Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul 135-720, Korea
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Diffusion-weighted imaging of the liver: usefulness of ADC values in the differential diagnosis of focal lesions and effect of ROI methods on ADC measurements. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2012; 26:303-12. [PMID: 23053714 DOI: 10.1007/s10334-012-0348-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 09/13/2012] [Accepted: 09/19/2012] [Indexed: 12/13/2022]
Abstract
OBJECT By measuring the apparent diffusion coefficient (ADC) of liver parenchyma and focal hepatic lesions (FHL) we proposed to investigate the utility of ADC in the differential diagnosis of hepatic disease and to determine the influence of region of interest (ROI) characteristics in those measurements. MATERIALS AND METHODS Ninety-three patients with at least one supracentimetric FHL, or parenchymal abnormality, were retrospectively evaluated. Diagnosis was based on histopathologic data or, alternatively, on a combination of consensus between imaging methods and 24 months of follow-up. Ninety lesions were evaluated with respiratory-triggered diffusion-weighted imaging (b values: 50 and 700 s/mm(2)): 14 hepatocellular carcinomas, 18 metastases, 10 focal nodular hyperplasias, four adenomas, 30 hemangiomas and 14 cysts. ADC of hepatic parenchyma was measured by placing ROIs in four different segments, and in FHLs by using three circular 1 cm(2) ROIs and one ROI encompassing the full lesion. Data was statistically analyzed (p < 0.05 considered significant), and a receiver operating characteristic curve was assessed to evaluate the accuracy for the diagnosis of malignancy. RESULTS Our measurements showed that parenchyma ADC was significantly higher in segment II and that ADCs of malignant lesions were significantly lower than those of benign lesions (p < 0.001). There was significant overlap between benign solid lesions and malignant lesions and the area under the curve for malignancy was 0.939 (sensitivity 89.7 %, specificity 90.6 %), using a cutoff of 1.43 × 10(-3) mm(2)/s. No significant difference was found between ROIs of different characteristics. CONCLUSION ADC measurements can help to characterize FHLs and differentiate normal from pathological parenchyma. Any ROI above 1 cm(2) can provide accurate ADC measurements in homogenous lesions.
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Ozaki M, Inoue Y, Miyati T, Hata H, Mizukami S, Komi S, Matsunaga K, Woodhams R. Motion artifact reduction of diffusion-weighted MRI of the liver: use of velocity-compensated diffusion gradients combined with tetrahedral gradients. J Magn Reson Imaging 2012; 37:172-8. [PMID: 22987784 DOI: 10.1002/jmri.23796] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 07/31/2012] [Indexed: 12/27/2022] Open
Abstract
PURPOSE To assess the effect of motion artifact reduction on the diffusion-weighted magnetic resonance imaging (DWI-MRI) of the liver, we compared velocity-compensated DWI (VC-DWI) and VC-DWI combined with tetrahedral gradients (t-VC-DWI) to conventional DWI (c-DWI) in the assessment of apparent diffusion coefficients (ADCs) of the liver. MATERIALS AND METHODS In 12 healthy volunteers, the liver was scanned with c-DWI, VC-DWI, and t-VC-DWI sequences. The signal-to-noise ratio (SNR) and ADC of the liver parenchyma were measured and compared among sequences. RESULTS The image quality was visually better for t-VC-DWI than for the others. The SNR for t-VC-DWI was significantly higher than that for VC-DWI (P < 0.05) and comparable to that for c-DWI. ADCs in both hepatic lobes were significantly lower for t-VC-DWI than for c-DWI (P < 0.01). ADC in the left lobe was significantly lower for VC-DWI than for c-DWI (P < 0.01). Although ADC in the left lobe was significantly higher for c-DWI (P < 0.01), no significant differences in ADCs were found between the right and left lobes for VC-DWI and t-VC-DWI. CONCLUSION The use of a t-VC-DWI sequence enables us to correct ADCs of the liver for artificial elevation due to cardiac motion, with preserved SNR.
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Affiliation(s)
- Masanori Ozaki
- School of Allied Health Sciences, Kitasato University, Kanagawa, Japan.
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Kim SY, Soo Lee S, Bumwoo Park, Kim N, Kim JK, Park SH, Byun JH, Song KJ, Koo JH, Kyung Choi E, Lee MG. Reproducibility of measurement of apparent diffusion coefficients of malignant hepatic tumors: Effect of DWI techniques and calculation methods. J Magn Reson Imaging 2012; 36:1131-8. [DOI: 10.1002/jmri.23744] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 05/24/2012] [Indexed: 01/17/2023] Open
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Effects of microperfusion in hepatic diffusion weighted imaging. Eur Radiol 2011; 22:891-9. [PMID: 22080250 PMCID: PMC3297749 DOI: 10.1007/s00330-011-2313-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 08/30/2011] [Accepted: 09/09/2011] [Indexed: 01/02/2023]
Abstract
OBJECTIVE Clinical hepatic diffusion weighted imaging (DWI) generally relies on mono-exponential diffusion. The aim was to demonstrate that mono-exponential diffusion in the liver is contaminated by microperfusion and that the bi-exponential model is required. METHODS Nineteen fasting healthy volunteers were examined with DWI (seven b-values) using fat suppression and respiratory triggering (1.5 T). Five different regions in the liver were analysed regarding the mono-exponentially fitted apparent diffusion coefficient (ADC), and the bi-exponential model: molecular diffusion (D (slow)), microperfusion (D (fast)) and the respective fractions (f (slow/fast)). Data were compared using ANOVA and Kruskal-Wallis tests. Simulations were performed by repeating our data analyses, using just the DWI series acquired with b-values approximating those of previous studies. RESULTS Median mono-exponentially fitted ADCs varied significantly (P < 0.001) between 1.107 and 1.423 × 10(-3) mm(2)/s for the five regions. Bi-exponential fitted D(slow) varied between 0.923 and 1.062 × 10(-3) mm(2)/s without significant differences (P = 0.140). D (fast) varied significantly, between 17.8 and 46.8 × 10(-3) mm(2)/s (P < 0.001). F-tests showed that the diffusion data fitted the bi-exponential model significantly better than the mono-exponential model (F > 21.4, P < 0.010). These results were confirmed by the simulations. CONCLUSION ADCs of normal liver tissue are significantly dependent on the measurement location because of substantial microperfusion contamination; therefore the bi-exponential model should be used. KEY POINTS Diffusion weighted MR imaging helps clinicians to differentiate tumours by diffusion properties. Fast moving water molecules experience microperfusion, slow molecules diffusion. Hepatic diffusion should be measured by bi-exponential models to avoid microperfusion contamination. Mono-exponential models are contaminated with microperfusion, resulting in apparent regional diffusion differences. Bi-exponential models are necessary to measure diffusion and microperfusion in the liver.
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Eatesam M, Noworolski SM, Tien PC, Nystrom M, Dodge JL, Merriman RB, Qayyum A. Liver diffusivity in healthy volunteers and patients with chronic liver disease: comparison of breathhold and free-breathing techniques. J Magn Reson Imaging 2011; 35:103-9. [PMID: 22034200 DOI: 10.1002/jmri.22748] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 07/18/2011] [Indexed: 01/21/2023] Open
Abstract
PURPOSE To compare liver ADC obtained with breathhold and free-breathing diffusion weighted imaging (DWI) in healthy volunteers and patients with liver disease. MATERIALS AND METHODS Twenty-eight subjects, 12 healthy volunteers and 16 patients (9 NAFLD, 7 chronic active HCV), underwent breathhold (BH) and free-breathing (FB) DWI MRI at 1.5 Tesla. Pearson's correlation coefficient was used to determine correlation while paired t-tests assessed differences between BH and FB ADC. Estimated bias was calculated using the Bland-Altman method. RESULTS Liver ADC (×10(-3) mm(2) /s) was lower on BH for all groups (mean difference 0.36 ± 0.20; P < 0.01). ADC was higher in healthy volunteers (BH 1.80 ± 0.18; FB 2.24 ± 0.20) compared with NAFLD patients (BH 1.43 ± 0.27; FB 1.78 ± 0.28) (P < 0.001) and HCV patients (BH 1.63 ± 0.191; FB 1.88 ± 0.12). Overall correlation between BH and FB ADC was (r = 0.75), greatest in NAFLD (r = 0.90) compared with the correlation in HCV (r = 0.24) and healthy subjects (r = 0.34). Bland-Altman plots did not show agreement in mean absolute difference and estimated bias between subjects. CONCLUSION Correlation between BH and FB liver ADC is moderate indicating that BH and FB should not be used interchangeably. Additionally, the lower ADC values in BH versus FB should be accounted for when comparing different liver DWI studies.
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Affiliation(s)
- Mamak Eatesam
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94143-0628, USA
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de Figueiredo EH, Borgonovi AF, Doring TM. Basic Concepts of MR Imaging, Diffusion MR Imaging, and Diffusion Tensor Imaging. Magn Reson Imaging Clin N Am 2011; 19:1-22. [DOI: 10.1016/j.mric.2010.10.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Park HY, Cho HJ, Kim EM, Hur G, Kim YH, Lee BH. Detection of Hepatic Lesion: Comparison of Free-Breathing and Respiratory-Triggered Diffusion-Weighted MR imaging on 1.5-T MR system. ACTA ACUST UNITED AC 2011. [DOI: 10.13104/jksmrm.2011.15.1.22] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Hye Young Park
- Department of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Korea
| | - Hyeon Je Cho
- Department of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Korea
| | - Eun-mi Kim
- Department of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Korea
| | - Gham Hur
- Department of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Korea
| | - Yong Hoon Kim
- Department of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Korea
| | - Byung Hoon Lee
- Department of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Korea
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Apparent diffusion coefficient measurement in a moving phantom simulating linear respiratory motion. Jpn J Radiol 2010; 28:578-83. [DOI: 10.1007/s11604-010-0476-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 06/07/2010] [Indexed: 10/18/2022]
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Holzapfel K, Bruegel M, Eiber M, Ganter C, Schuster T, Heinrich P, Rummeny EJ, Gaa J. Characterization of small (≤10mm) focal liver lesions: Value of respiratory-triggered echo-planar diffusion-weighted MR imaging. Eur J Radiol 2010; 76:89-95. [DOI: 10.1016/j.ejrad.2009.05.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2009] [Revised: 03/22/2009] [Accepted: 05/07/2009] [Indexed: 12/13/2022]
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Do RKG, Chandarana H, Felker E, Hajdu CH, Babb JS, Kim D, Taouli B. Diagnosis of liver fibrosis and cirrhosis with diffusion-weighted imaging: value of normalized apparent diffusion coefficient using the spleen as reference organ. AJR Am J Roentgenol 2010; 195:671-6. [PMID: 20729445 DOI: 10.2214/ajr.09.3448] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE The purpose of this study is to compare the diagnostic accuracy of liver apparent diffusion coefficient (ADC) versus normalized liver ADC using the spleen as a reference organ for the diagnosis of liver fibrosis and cirrhosis. MATERIALS AND METHODS Fifty-six patients, 34 with liver disease and 22 control subjects, were assessed with breath-hold single-shot echo-planar diffusion-weighted imaging using b values of 0, 50, and 500 s/mm(2). Liver ADC and normalized liver ADC (defined as the ratio of liver ADC to spleen ADC) were compared between patients stratified by fibrosis stage. Receiver operating characteristic (ROC) analysis was used to determine the performance of ADC and normalized liver ADC for prediction of liver fibrosis and cirrhosis. Reproducibility was assessed by measuring coefficient of variation (n = 7). RESULTS Liver ADC failed to distinguish individual stages of fibrosis, except between stages 0 and 4. There were significant differences in normalized liver ADC between control livers and intermediate stages of fibrosis (stages 2-3) and cirrhosis (stage 4) and between stages 1 and 4, and there was a trend toward significance between stages 0 and 1 (p = 0.051) and stages 1 and 3 (p = 0.06). ROC analysis showed that normalized liver ADC was superior to liver ADC for detection of stage > or = 2 (area under the ROC curve, 0.864 vs 0.655; p = 0.013) and stage > or =3 (0.805 vs 0.689; p = 0.015), without a difference for diagnosing cirrhosis (0.935 vs 0.720; p = 0.185). Normalized liver ADC had higher reproducibility than ADC (mean coefficient of variation, 3.5% vs 12.6%). CONCLUSION Our results suggest that normalizing liver ADC with spleen ADC improves diagnostic accuracy for detection of liver fibrosis and cirrhosis when using breath-hold diffusion-weighted imaging, with better reproducibility.
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Affiliation(s)
- Richard K G Do
- Department of Radiology, New York University Langone Medical Center, New York, NY 10029, USA
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Lu TLC, Meuli RA, Marques-Vidal PM, Bize P, Denys A, Schmidt S. Interobserver and intraobserver variability of the apparent diffusion coefficient in treated malignant hepatic lesions on a 3.0T machine: Measurements in the whole lesion versus in the area with the most restricted diffusion. J Magn Reson Imaging 2010; 32:647-53. [DOI: 10.1002/jmri.22301] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Diffusion tensor imaging (DTI) of the kidney at 3 tesla-feasibility, protocol evaluation and comparison to 1.5 Tesla. Invest Radiol 2010; 45:245-54. [PMID: 20375845 DOI: 10.1097/rli.0b013e3181d83abc] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE The purpose of this study was to evaluate the feasibility of diffusion tensor imaging of the kidney at a field strength of 3T. We assessed fractional anisotropy (FA) and apparent diffusion coefficients (ADC) of various acquisition protocols and determined the reproducibility of these measurements. FA, ADC, signal-to-noise ratios (SNR), and contrast-to-noise ratios (CNR) were compared with those acquired at 1.5T. MATERIAL AND METHODS Ten healthy volunteers were examined with a respiratory-triggered echo-planar imaging sequence (TR: 1800 ms, TE: 58 ms, b = 0, 300 s/mm(2)) on a 3-Tesla whole-body MR scanner. Protocol variations included diffusion measurements during free-breathing, in 6 or 12 directions, and an additional b-value of 50 s/mm(2). A breath-hold protocol was also integrated (TR: 820 ms, TE: 58 ms, b = 0, 300 s/mm(2)). Measurements with 2 b-values and 6 diffusion directions were also acquired at 1.5 T. SNR was calculated with the difference-image method. Statistical analysis was performed with Wilcoxon signed-rank tests. Intrareader correlation was assessed with weighted kappa coefficients and reproducibility with the root-mean-square-average and the Bland-Altman-method. RESULTS At 3T, SNR of cortex and medulla and CNR of cortex/medulla were significantly higher than at 1.5T, leading to improved corticomedullary discrimination. There were no significant FA- and ADC differences with 2 b-values and 6 diffusion directions between measurements at 1.5T and 3T. FA of the medulla was significantly higher than that of the cortex in all measurements. Tractography visualized a typical radial diffusion direction in the medulla. Best image quality was achieved with a respiratory triggered protocol with 12 acquisition directions. Measurements with 3 b-values led to decreased ADCs. Acquisition in 12 directions resulted in decreased cortical FA. FA and ADC of breath-hold and free-breathing acquisitions were significantly higher than that of the respiratory-triggered protocol. Intrareader correlation ranged from kappa 0.60 to 0.96. Variance of the respiratory-triggered protocol was smaller than that of breath-hold and free-breathing protocols. Variance was highest for medullary FA in all protocols with reproducibility coefficients ranging from 0.36 to 0.46. CONCLUSION Diffusion tensor imaging of the kidney at 3T is feasible and yields significantly higher SNR and CNR. FA and ADCs do not significantly differ from 1.5T. Number of b-values influences ADC-values. Acquisitions in 12 directions provide lower cortical FA-values. We recommend a respiratory-triggered protocol because of improved image quality and reproducibility.
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Notohamiprodjo M, Reiser MF, Sourbron SP. Diffusion and perfusion of the kidney. Eur J Radiol 2010; 76:337-47. [PMID: 20580179 DOI: 10.1016/j.ejrad.2010.05.033] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 05/28/2010] [Indexed: 01/18/2023]
Abstract
MRI of the kidney currently makes the transition from depiction of morphology to assessment of function. Functional renal imaging methods provide information on diffusion and perfusion on a microstructural level. This review article presents the current status of functional renal imaging with focus on DWI (diffusion-weighted imaging) and DCE-MRI (dynamic contrast-enhanced MRI), as well as BOLD (blood-oxygenation level dependent) MRI, DTI (diffusion tensor imaging) and arterial spin labeling (ASL). Technical background of these techniques is explained and clinical assessment of renal function, parenchymal disease, transplant function and solid masses is discussed.
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Affiliation(s)
- Mike Notohamiprodjo
- Department of Clinical Radiology, University Hospitals Munich, Campus Großhadern, Marchioninistrasse 15, 81377 Munich, Germany.
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Kim SY, Lee SS, Byun JH, Park SH, Kim JK, Park B, Kim N, Lee MG. Malignant Hepatic Tumors: Short-term Reproducibility of Apparent Diffusion Coefficients with Breath-hold and Respiratory-triggered Diffusion-weighted MR Imaging. Radiology 2010; 255:815-23. [DOI: 10.1148/radiol.10091706] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Diffusion-weighted magnetic resonance imaging of the liver using tracking only navigator echo: feasibility study. Invest Radiol 2010; 45:57-63. [PMID: 20057318 DOI: 10.1097/rli.0b013e3181cc25ed] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE To introduce and assess the TRacking Only Navigator echo (TRON) technique for diffusion-weighted magnetic resonance imaging (DWI) of the liver. SUBJECTS AND METHODS A total of 10 volunteers underwent TRON, respiratory triggered (RT), and free breathing (FB) DWI of the liver. Scan times of TRON and RT DWI were measured, and image sharpness in TRON, RT, and FB DWI was assessed and compared using nonparametric tests. Furthermore, 14 patients with liver metastasis who had undergone TRON and RT DWI of the liver were retrospectively assessed. Relative contrast ratios (RCRs) and apparent diffusion coefficients (ADCs) of the largest hepatic metastasis in TRON and RT DWI were measured. RCRs were compared using a parametric test and agreement in ADCs was assessed using the Bland-Altman method. RESULTS In the volunteers, mean scan times of TRON and RT relative to FB DWI were 110% to 112% and 261% to 290%, respectively. On axial images, there were no significant differences in images sharpness among TRON, RT, and FB DWI, but on coronal images image sharpness in TRON was nearly always significantly better (P < 0.05) than in RT and FB DWI. In the patients, mean RCRs between TRON and RT DWI were not significantly different (P = 0.9091). Mean difference in ADC +/- limits of agreement (in 10 mm/s) between TRON and RT DWI was -0.16 +/- 0.79. CONCLUSION TRON offers sharp diffusion-weighted images of the liver using an efficient scan time, making it an excellent alternative to RT and FB DWI. The moderate to poor agreement in ADCs of liver metastases between TRON and RT DWI requires further investigation.
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Ivancevic MK, Kwee TC, Takahara T, Ogino T, Hussain HK, Liu PS, Chenevert TL. Diffusion-weighted MR imaging of the liver at 3.0 Tesla using TRacking Only Navigator echo (TRON): a feasibility study. J Magn Reson Imaging 2010; 30:1027-33. [PMID: 19856431 DOI: 10.1002/jmri.21939] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To assess the feasibility of TRacking Only Navigator echo (TRON) for diffusion-weighted magnetic resonance imaging (DWI) of the liver at 3.0T. MATERIALS AND METHODS Ten volunteers underwent TRON, respiratory triggered, and free breathing DWI of the liver at 3.0 Tesla (T). Scan times were measured. Image sharpness, degree of stair-step and stripe artifacts for the three methods were assessed by two observers. RESULTS Mean scan times of TRON and respiratory triggered DWI relative to free breathing DWI were 34% and 145% longer respectively. In four of eight comparisons (two observers, two b-values, two slice orientations), TRON DWI image sharpness was significantly better than free breathing DWI, but inferior to respiratory triggered DWI. In two of four comparisons (two observers, two b-values), degree of stair-step artifacts in TRON DWI was significantly lower than in respiratory triggered DWI. Degree of stripe artifacts between the three methods was not significantly different. CONCLUSION DWI of the liver at 3.0T using TRON is feasible. Image sharpness in TRON DWI is superior to that in free breathing DWI. Although image sharpness of respiratory triggered DWI is still better, TRON DWI requires less scan time and reduces stair-step artifacts.
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Abstract
Magnetic resonance (MR) imaging plays an increasingly important role in the evaluation of patients with liver disease because of its high contrast resolution, lack of ionizing radiation, and the possibility of performing functional imaging sequences. With advances in hardware and coil systems, diffusion-weighted (DW) MR imaging can now be applied to liver imaging with improved image quality. DW MR imaging enables qualitative and quantitative assessment of tissue diffusivity (apparent diffusion coefficient) without the use of gadolinium chelates, which makes it a highly attractive technique, particularly in patients with severe renal dysfunction at risk for nephrogenic systemic fibrosis. In this review, acquisition parameters, postprocessing, and quantification methods applied to liver DW MR imaging will be discussed. The current clinical uses of DW MR imaging (liver lesion detection and characterization, compared and combined with conventional sequences) and the emerging applications of DW MR imaging (tumor treatment response and diagnosis of liver fibrosis and cirrhosis) will be reviewed. Also, limitations, mainly image quality and reproducibility of diffusion parameters, and future directions of liver DW MR imaging will be discussed.
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Affiliation(s)
- Bachir Taouli
- Department of Radiology, New York University Medical Center, New York, NY, USA.
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Kwee TC, Takahara T, Niwa T, Ivancevic MK, Herigault G, Van Cauteren M, Luijten PR. Influence of cardiac motion on diffusion-weighted magnetic resonance imaging of the liver. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2009; 22:319-25. [PMID: 19727877 DOI: 10.1007/s10334-009-0183-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 08/03/2009] [Accepted: 08/12/2009] [Indexed: 12/21/2022]
Abstract
PURPOSE To assess cardiac motion-induced signal loss in diffusion-weighted magnetic resonance imaging (DWI) of the liver using dynamic DWI. MATERIALS AND METHODS Three volunteers underwent dynamic coronal DWI of the liver under breathholding, in the diastolic (DWI(diast)) or systolic (DWI(syst)) cardiac phase, and with motion probing gradients (MPGs) in phase encoding (P, left-right), frequency encoding (M, superior-inferior), or slice select (S, anterior-posterior) direction. Liver-to-background contrasts (LBCs) of DWI(syst) were compared to those of DWI(diast), for both the left and right liver lobes, using nonparametric tests. Signal decrease ratios (SDRs) were calculated as (1-(LBCDWI(syst)/LBCDWI(diast))) x 100%. DWI(syst) was further analyzed to determine which direction of MPGs was most affected by cardiac motion. RESULTS In the left liver lobe, LBCs of DWI(syst) (median 3.35) were significantly lower (P < 0.0001) than those of DWI(diast) (median 4.84). In the right liver lobe, LBCs of DWI(syst) (median 4.17) were also significantly lower (P < 0.0001) than those of DWI(diast) (median 5.35 ). SDRs of the left and right liver lobes were 25.5% and 17.3%, respectively. In DWI(syst), the significantly lowest (P < 0.05) LBCs were observed in the M direction (left liver lobe) and P direction (right liver lobe) of MPGs. CONCLUSION Signal intensity of both liver lobes are affected by cardiac motion in DWI. In the left liver lobe, signal loss especially occurs in the superior-inferior direction of MPGs, whereas in the right lobe, signal loss especially occurs in the left-right direction of MPGs.
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Affiliation(s)
- Thomas C Kwee
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
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Nasu K, Kuroki Y, Minami M. Feasibility of diffusion-weighted imaging under split breath-hold acquisition and postprocessing (DWI-SBAP): an attempt to suppress hepatic pseudo-anisotropy. Jpn J Radiol 2009; 27:78-85. [DOI: 10.1007/s11604-008-0303-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Accepted: 11/18/2008] [Indexed: 12/27/2022]
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Kwee TC, Takahara T, Koh DM, Nievelstein RAJ, Luijten PR. Comparison and reproducibility of ADC measurements in breathhold, respiratory triggered, and free-breathing diffusion-weighted MR imaging of the liver. J Magn Reson Imaging 2009; 28:1141-8. [PMID: 18972355 DOI: 10.1002/jmri.21569] [Citation(s) in RCA: 185] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
PURPOSE To compare and determine the reproducibility of apparent diffusion coefficient (ADC) measurements of the normal liver parenchyma in breathhold, respiratory triggered, and free-breathing diffusion-weighted magnetic resonance imaging (DWI). MATERIALS AND METHODS Eleven healthy volunteers underwent three series of DWI. Each DWI series consisted of one breathhold, one respiratory triggered, and two free-breathing (thick and thin slice acquisition) scans of the liver, at b-values of 0 and 500 s/mm2. ADCs of the liver parenchyma were compared by using nonparametric tests. Reproducibility was assessed by the Bland-Altman method. RESULTS Mean ADCs (in 10(-3) mm2/sec) in respiratory triggered DWI (2.07-2.27) were significantly higher than mean ADCs in breathhold DWI (1.57-1.62), thick slice free-breathing DWI (1.62-1.65), and thin slice free-breathing DWI (1.57-1.66) (P<0.005). Ranges of mean difference in ADC measurement+/-limits of agreement between two scans were -0.02-0.05+/-0.16-0.24 in breathhold DWI, -0.14-0.20+/-0.59-0.60 in respiratory triggered DWI, -0.03-0.03+/-0.20-0.29 in thick slice free-breathing DWI, and -0.01-0.09+/-0.21-0.29 in thin slice free-breathing DWI. CONCLUSION ADC measurements of the normal liver parenchyma in respiratory triggered DWI are significantly higher and less reproducible than in breathhold and free-breathing DWI.
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Affiliation(s)
- Thomas C Kwee
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
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