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Mao W, Ding Y, Ding X, Fu C, Zeng M, Zhou J. Diffusion kurtosis imaging for the assessment of renal fibrosis of chronic kidney disease: A preliminary study. Magn Reson Imaging 2021; 80:113-120. [PMID: 33971241 DOI: 10.1016/j.mri.2021.05.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 04/30/2021] [Accepted: 05/05/2021] [Indexed: 01/18/2023]
Abstract
PURPOSE To investigate the potential of diffusion kurtosis imaging (DKI) for the assessment of renal fibrosis in chronic kidney disease (CKD), using histopathology as the reference standard. METHODS Eighty-nine CKD patients and twenty healthy volunteers were recruited in this study. DKI was performed in all participants and all CKD patients received renal biopsy. The values of mean diffusivity (MD) and mean kurtosis (MK) in the renal cortex and medulla were compared between CKD patients and healthy volunteers. The Spearman correlation coefficient was calculated to assess the relationship between MD, MK values and the estimated glomerular filtration rate (eGFR), serum creatinine (SCr), 24 h urinary protein (24 h-UPRO), histopathological fibrosis score. RESULTS The medullary MD values were significantly lower than cortex, while the cortical MK values were significantly lower than medulla for all participants. Renal parenchymal MD values were significantly lower in the CKD patients than healthy controls, whereas MK values were significantly higher in the CKD patients than healthy controls. In the CKD patients, the significantly negative correlation was observed between the renal parenchymal MD values and the 24 h-UPRO, SCr, histopathological fibrosis score, as well as between the renal parenchymal MK values and the eGFR, while the significantly positive correlation was found between the renal parenchymal MD values and the eGFR, as well as between the renal parenchymal MK values and the 24 h-UPRO, SCr, histopathological fibrosis score. CONCLUSION DKI shows great potential in the noninvasive assessment of renal fibrosis in CKD.
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Affiliation(s)
- Wei Mao
- Department of Radiology, Zhongshan Hospital, Fudan University; Shanghai Institute of Medical Imaging, 180 Fenglin Road, Shanghai 200032, People's Republic of China
| | - Yuqin Ding
- Department of Radiology, Zhongshan Hospital, Fudan University; Shanghai Institute of Medical Imaging, 180 Fenglin Road, Shanghai 200032, People's Republic of China
| | - Xiaoqiang Ding
- Department of Nephrology, Zhongshan Hospital, Fudan University; 180 Fenglin Road, Shanghai 200032, People's Republic of China
| | - Caixia Fu
- Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, People's Republic of China
| | - Mengsu Zeng
- Department of Radiology, Zhongshan Hospital, Fudan University; Shanghai Institute of Medical Imaging, 180 Fenglin Road, Shanghai 200032, People's Republic of China.
| | - Jianjun Zhou
- Department of Radiology, Zhongshan Hospital, Fudan University; Shanghai Institute of Medical Imaging, 180 Fenglin Road, Shanghai 200032, People's Republic of China; Department of Radiology, Xiamen Branch, Zhongshan Hospital, Fudan University, Xiamen, China.
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Mao W, Zhou J, Zeng M, Ding Y, Qu L, Chen C, Ding X, Wang Y, Fu C, Gu F. Intravoxel incoherent motion diffusion-weighted imaging for the assessment of renal fibrosis of chronic kidney disease: A preliminary study. Magn Reson Imaging 2017; 47:118-124. [PMID: 29217491 DOI: 10.1016/j.mri.2017.12.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/12/2017] [Accepted: 12/04/2017] [Indexed: 11/19/2022]
Abstract
PURPOSE To investigate the potential of Intravoxel incoherent motion diffusion-weighted imaging(IVIM-DWI) for the assessment of renal fibrosis in chronic kidney disease (CKD), using histopathology as a reference standard. METHODS Eighty-five CKD patients and twenty healthy volunteers were recruited in this study. IVIM-DWI was performed in all of the participants, and all of the CKD patients underwent renal biopsy. The mean values of the true diffusion coefficient (D), pseudo diffusion coefficient (D*) and perfusion fraction (f) in the renal cortex and medulla were compared between the CKD patients and healthy volunteers. The Spearman correlation coefficient was calculated to assess the relationship between the D, D*,f values and the estimated glomerular filtration rate (eGFR), serum creatinine level (SCr), 24h urinary protein level (24h-UPRO), histopathological fibrosis scores. RESULTS The D, D* and f values were significantly lower in medulla than in the cortex for all of the participants. All of the IVIM parameters were significantly lower in the CKD patients than in the healthy controls. In the CKD patients, a significant negative correlation was found between the renal parenchymal D, D*,f values and the 24h-UPRO, as well as between the renal parenchymal D, f values and the SCr. There was a significant positive correlation between all of the IVIM parameters and the eGFR. All of the IVIM parameters exhibited a significant negative correlation with the histopathological fibrosis score. CONCLUSION IVIM-DWI shows great potential in the noninvasive assessment of renal fibrosis in CKD.
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Affiliation(s)
- Wei Mao
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai 200032, People's Republic of China
| | - Jianjun Zhou
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai 200032, People's Republic of China.
| | - Mengsu Zeng
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai 200032, People's Republic of China
| | - Yuqin Ding
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai 200032, People's Republic of China
| | - Lijie Qu
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai 200032, People's Republic of China
| | - Caizhong Chen
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai 200032, People's Republic of China.
| | - Xiaoqiang Ding
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, People's Republic of China.
| | - Yaqiong Wang
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, People's Republic of China.
| | - Caixia Fu
- Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen 518057, People's Republic of China.
| | - Feng Gu
- Department of Radiology, Nantong Second People's Hospital, Nantong 226000, People's Republic of China.
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Mao W, Zhou J, Zeng M, Ding Y, Qu L, Chen C, Ding X, Wang Y, Fu C. Chronic kidney disease: Pathological and functional evaluation with intravoxel incoherent motion diffusion-weighted imaging. J Magn Reson Imaging 2017; 47:1251-1259. [PMID: 28940646 DOI: 10.1002/jmri.25861] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/07/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Because chronic kidney disease (CKD) is a worldwide problem, accurate pathological and functional evaluation is required for planning treatment and follow-up. Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) can assess both capillary perfusion and tissue diffusion and may be helpful in evaluating renal function and pathology. PURPOSE To evaluate functional and pathological alterations in CKD by applying IVIM-DWI. STUDY TYPE Prospective study. SUBJECTS In all, 72 CKD patients who required renal biopsy and 20 healthy volunteers. FIELD STRENGTH 1.5T. ASSESSMENT All subjects underwent IVIM-DWI of the kidneys, and image analysis was performed by two radiologists. The mean values of true diffusion coefficient (D), pseudo diffusion coefficient (D*), and perfusion fraction (f) were acquired from renal parenchyma. Correlation between IVIM-DWI parameters and estimated glomerular filtration rate (eGFR), as well as pathological damage, were assessed. STATISTICAL TESTS One-way analysis of variance (ANOVA), paired sample t-test and Spearman correlation analysis. RESULTS The paired sample t-test revealed that IVIM-DWI parameters were significantly lower in medulla than cortex for both patients and controls (P < 0.01). Regardless of whether eGFR was reduced, ANOVA revealed that f values of renal parenchyma were significantly lower in patients than controls (P < 0.05). Spearman correlation analysis revealed that there were positive correlations between eGFR and D (cortex, r = 0.466, P < 0.001; medulla, r = 0.491, P < 0.001), and between eGFR and f (cortex, r = 0.713, P < 0.001; medulla, r = 0.512, P < 0.001). Negative correlations were found between f and glomerular injury (cortex, r = -0.773, P < 0.001; medulla, r = -0.629, P < 0.001), and between f and tubulointerstitial lesion (cortex, r = -0.728, P < 0.001; medulla, r = -0.547, P < 0.001). DATA CONCLUSION IVIM-DWI might be feasible for noninvasive evaluation of renal function and pathology of CKD, especially in detection of renal insufficiency at an early stage. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1251-1259.
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Affiliation(s)
- Wei Mao
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai, P.R. China
| | - Jianjun Zhou
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai, P.R. China
| | - Mengsu Zeng
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai, P.R. China
| | - Yuqin Ding
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai, P.R. China
| | - Lijie Qu
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai, P.R. China
| | - Caizhong Chen
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, Shanghai, P.R. China
| | - Xiaoqiang Ding
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, P.R. China
| | - Yaqiong Wang
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, P.R. China
| | - Caixia Fu
- Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, P.R. China
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Albayrak E, Sahin S. Evaluation of upper abdominal organs with DWI in patients with familial Mediterranean fever. Abdom Radiol (NY) 2017; 42:1393-1399. [PMID: 27909774 DOI: 10.1007/s00261-016-1005-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE To investigate the diagnostic efficiency of diffusion-weighted magnetic resonance imaging (DWI) for the evaluation of functional changes that can occur in upper abdominal organs in patients with familial Mediterranean fever (FMF). METHODS The study included 50 controls, 45 patients with FMF, and 14 patients with FMF who had accompanying proteinuria. Measurement of apparent diffusion coefficient (ADC) was performed using DWI sections obtained from liver, spleen, kidney, and pancreas parenchyma with 1.5T MRI using b = 500 and b = 1000 s/mm2 values both in patients and control groups. Mean ADC values were compared between patient and control groups. RESULTS Renal ADC values were lower in the patient groups compared to the control group. Additionally, renal ADC values showed further decrease in the patient group in the presence of accompanying proteinuria, when compared to the FMF group without proteinuria (p < 0.001). Based on the ROC analysis, calculated cutoff values for the determination of FMF and FMF accompanied by proteinuria were 2.26 × 10-3 and 2.04 × 10-3 mm2/s, respectively. Liver, spleen, and pancreas ADC values did not show remarkable change between patient and control groups. CONCLUSION Present findings indicate that the presence of FMF and its clinical progression expressed by proteinuria can be differentially determined with renal DWI.
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Liu B, Cai J, Zhu J, Zheng H, Zhang Y, Wang L. Diffusion Tensor Imaging for Evaluating Biliary Atresia in Infants and Neonates. PLoS One 2016; 11:e0168477. [PMID: 27992499 PMCID: PMC5167545 DOI: 10.1371/journal.pone.0168477] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 12/01/2016] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Preliminary studies have shown that diffusion tensor imaging (DTI) is helpful in evaluating liver disorders. However, there is no published literature on the use of DTI in the diagnosis of biliary atresia (BA). This study aimed to investigate the diagnostic value of the liver average apparent diffusion coefficient (ADC) and fractional anisotropy (FA) measured using DTI for BA in neonates and infants. METHODS Fifty-nine patients with infant jaundice were included in this study. DTI was performed with b factors of 0 and 1000 s/mm2. Liver fibrosis in the BA group was determined and graded (F0, F1, F2, F3, F4) based on the pathological findings. Statistical analyses were performed to determine the diagnostic accuracy of DTI for BA. RESULTS The ADC value was significantly lower in the BA group [(1.262±0.127)×10-3 mm2/s] than in the non-BA group [(1.430±0.149)×10-3 mm2/s, (P<0.001)]. The area under the receiver operating characteristic curve was 0.805±0.058 (P<0.001) for ADC. With a cut-off value of 1.317×10-3 mm2/s, ADC achieved a sensitivity of 75% and a specificity of 81.5% for the differential diagnosis of BA and non-BA. In the BA group, the ADC value was significantly correlated with fibrotic stage. Further analysis showed that the ADC value of stage F0 was significantly higher than that of stages F1, F2, F3 and F4, whereas there were no significant differences among stages F1, F2, F3 and F4. CONCLUSION Hepatic ADC measured with DTI can be used as an adjunct to other noninvasive imaging methods in the differential diagnosis of BA and non-BA. ADC was helpful in detecting liver fibrosis but not in differentiating the fibrotic grades.
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Affiliation(s)
- Bo Liu
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Jinhua Cai
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
- * E-mail:
| | - Jin Zhu
- Department of Pathology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Helin Zheng
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Yun Zhang
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Longlun Wang
- Department of Radiology, Children’s Hospital of Chongqing Medical University, Chongqing, China
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Backens M. [Basic principles and technique of diffusion-weighted imaging and diffusion tensor imaging]. Radiologe 2016; 55:762-70. [PMID: 26330214 DOI: 10.1007/s00117-015-0004-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Due to their thermal energy, water molecules in tissue are in continuous random motion called diffusion. Water diffusion in pathologically modified tissue (e. g. ischemia, inflammation and neoplasia) is different from normal conditions. Diffusion-weighted magnetic resonance (MR) imaging (DWI) can measure the local strength and main direction of the diffusional motion in any picture element, thus providing diagnostic tissue information exceeding the morphological depiction. METHODS Diffusion-weighted MR sequences are based on the echo planar imaging (EPI) technique which is very rapid but also susceptible to artefacts. Using especially strong magnetic field gradient pulses the MR signal is sensitized to microscopic motion of water molecules resulting in a unique image contrast in addition to T1 and T2. Local deviations of the diffusion strength from normal values indicate pathological processes. The DWI sequences can measure diffusion along any direction; however, in the clinical routine only directionally averaged DWI images (trace maps) are used. Diffusion tensor imaging (DTI) represents an advanced DWI method which specifically explores diffusional anisotropy in order to obtain additional information about tissue microstructure. CONCLUSION Diffusion-weighted MRI is an established technique for the assessment of pathological processes. Although DWI is mainly applied in stroke diagnostics, it is increasingly being used to detect and characterize various lesions in the brain as well as in the whole body. With new sequence techniques imaging artefacts can be significantly reduced. In addition, DTI allows the reconstruction and 3-dimensional visualization of tissue fibre structure. This method has proven to be clinically important primarily for the depiction of nerve tracts in the brain and spinal cord when planning surgical interventions and radiation therapy.
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Affiliation(s)
- M Backens
- Klinik für Diagnostische und Interventionelle Neuroradiologie, Universitätsklinikum des Saarlandes, Kirrberger Straße, 66421, Homburg/Saar, Deutschland.
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Yao XZ, Kuang T, Wu L, Feng H, Liu H, Cheng WZ, Rao SX, Wang H, Zeng MS. Comparison of diffusion-weighted MRI acquisition techniques for normal pancreas at 3.0 Tesla. Diagn Interv Radiol 2015; 20:368-73. [PMID: 25010365 DOI: 10.5152/dir.2014.13454] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE We aimed to optimize diffusion-weighted imaging (DWI) acquisitions for normal pancreas at 3.0 Tesla. MATERIALS AND METHODS Thirty healthy volunteers were examined using four DWI acquisition techniques with b values of 0 and 600 s/mm2 at 3.0 Tesla, including breath-hold DWI, respiratory-triggered DWI, respiratory-triggered DWI with inversion recovery (IR), and free-breathing DWI with IR. Artifacts, signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) of normal pancreas were statistically evaluated among different DWI acquisitions. RESULTS Statistical differences were noticed in artifacts, SNR, and ADC values of normal pancreas among different DWI acquisitions by ANOVA (P <0.001). Normal pancreas imaging had the lowest artifact in respiratory-triggered DWI with IR, the highest SNR in respiratory-triggered DWI, and the highest ADC value in free-breathing DWI with IR. The head, body, and tail of normal pancreas had statistically different ADC values on each DWI acquisition by ANOVA (P < 0.05). CONCLUSION The highest image quality for normal pancreas was obtained using respiratory-triggered DWI with IR. Normal pancreas displayed inhomogeneous ADC values along the head, body, and tail structures.
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Affiliation(s)
- Xiu-Zhong Yao
- Department of Radiology, Zhongshan Hospital of Fudan University, Shanghai, China; Department of Medical Imaging, Shanghai Institute of Medical Imaging, Shanghai Medical College of Fudan University, Shanghai, China.
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Differentiation of malignant from benign focal splenic lesions: added value of diffusion-weighted MRI. AJR Am J Roentgenol 2014; 203:803-12. [PMID: 25247945 DOI: 10.2214/ajr.13.11914] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The objective of our study was to evaluate the added value of diffusion-weighted imaging (DWI) for distinguishing between malignant and benign focal splenic lesions. MATERIALS AND METHODS This study included 53 patients with 11 malignant and 42 benign splenic lesions who underwent gadoxetic acid-enhanced MRI and DWI. Qualitative and quantitative analyses were conducted for splenic lesions. Two blinded observers evaluated the two image sets--that is, the conventional MR images alone versus the combined conventional MR and DW images--and scored their confidence for malignancy of splenic lesions. The Fisher exact test and Mann-Whitney U test were performed, and diagnostic performance values (ROC curve analysis) were evaluated. RESULTS All malignant lesions showed a progressive hypovascular enhancement pattern, whereas the hypervascular enhancement patterns were shown in only benign lesions (n = 20, 47.6%) (p < 0.05). The mean apparent diffusion coefficient (ADC) of the malignant lesions (0.73 × 10(-3) mm(2)/s) was significantly lower than that of the benign lesions (1.21 × 10(-3) mm(2)/s) (p < 0.001). The addition of DW images to conventional MR images showed a significant improvement for predicting malignant splenic lesions (area under ROC curve [Az] without DW images vs with DW images: 0.774 vs 0.983 for observer 1 and 0.742 vs 0.986 for observer 2) (p < 0.001). In addition, the diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of combined conventional MR and DW images were higher than those of conventional MR images alone. CONCLUSION The addition of DWI to conventional MRI improves differentiation of malignant from benign splenic lesions.
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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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Jang KM, Kim SH, Lee SJ, Lee MW, Choi D, Kim KM. Upper abdominal gadoxetic acid-enhanced and diffusion-weighted MRI for the detection of gastric cancer: Comparison with two-dimensional multidetector row CT. Clin Radiol 2014; 69:827-35. [PMID: 24837701 DOI: 10.1016/j.crad.2014.03.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 03/19/2014] [Accepted: 03/25/2014] [Indexed: 01/15/2023]
Abstract
AIM To evaluate the diagnostic performance of abdominal magnetic resonance imaging (MRI) for the detection of gastric cancer in comparison with that of two-dimensional (2D) multidetector row computed tomography (CT). MATERIALS AND METHODS The study included 189 patients with 170 surgically confirmed gastric cancers and 19 patients without gastric cancer, all of whom underwent gadoxetic acid-enhanced MRI with diffusion-weighted (DW) imaging, and multidetector contrast-enhanced abdominal CT imaging. Two observers independently analysed three sets of images (CT set, conventional MRI set, and combined conventional and DW MRI set). A five-point scale for likelihood of gastric cancer was used. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were evaluated. Quantitative [apparent diffusion coefficient (ADC) analyses with Mann-Whitney U-test were conducted for gastric cancers and the nearby normal gastric wall. RESULTS The diagnostic accuracy and sensitivity for detection of gastric cancer were significantly higher on combined conventional and DW MRI set (77.8-78.3%; 75.3-75.9%) than the CT imaging set (67.7-71.4%; 64.1-68.2%) or the conventional MRI set (72-73%; 68.8-70%; p < 0.01). In particular, for gastric cancers with pT2 and pT3, the combined conventional and DW MRI set (91.6-92.6%) yielded significantly higher sensitivity for detection of gastric cancer than did the CT imaging set (76.8-81.1%) by both observers (p < 0.01). The mean ADC of gastric cancer lesions (1 ± 0.23 × 10(-3) mm(2)/s) differed significantly from that of normal gastric wall (1.77 ± 0.25 × 10(-3) mm(2)/s; p < 0.01). CONCLUSION Abdominal MRI with DW imaging was more sensitive for the detection of gastric cancer than 2D-multidetector row CT or conventional MRI alone.
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Affiliation(s)
- K M Jang
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, South Korea
| | - S H Kim
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, South Korea.
| | - S J Lee
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, South Korea
| | - M W Lee
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, South Korea
| | - D Choi
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, South Korea
| | - K M Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, South Korea
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Diffusion-weighted imaging in assessing renal pathology of chronic kidney disease: A preliminary clinical study. Eur J Radiol 2014; 83:756-62. [DOI: 10.1016/j.ejrad.2014.01.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/21/2014] [Accepted: 01/30/2014] [Indexed: 11/20/2022]
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Yao X, Kuang T, Wu L, Feng H, Liu H, Cheng W, Rao S, Wang H, Zeng M. Optimization of MR diffusion-weighted imaging acquisitions for pancreatic cancer at 3.0T. Magn Reson Imaging 2014; 32:875-9. [PMID: 24848293 DOI: 10.1016/j.mri.2014.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 03/03/2014] [Accepted: 04/15/2014] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To investigate and optimize diffusion-weighted imaging (DWI) acquisitions for pancreatic cancer at 3.0T. METHODS Forty-five patients with pancreatic cancer were examined by four DWI acquisitions with b values=0 and 600s/mm(2) at 3.0T, including breath-holding DWI (BH-DWI), respiratory-triggered DWI (TRIG-DWI), respiratory-triggered DWI with inversion-recovery technique (TRIGIR-DWI), and free-breathing DWI with inversion-recovery technique (FBIR-DWI). Artifacts, contrast ratio (CR), contrast-to-noise ratio (CNR) and apparent diffusion coefficient (ADC) of pancreatic cancer were statistically compared among DWI acquisitions. RESULTS TRIGIR-DWI displayed the lowest artifacts and highest CR compared to other DWI acquisitions. CNRs of pancreatic cancer in TRIG-DWI and TRIGIR-DWI were statistically higher than that in FBIR-DWI and BH-DWI. Different ADCs between pancreatic cancer and noncancerous pancreatic tissues were noticed by a paired-samples T test in TRIG-DWI (p=0.017), TRIGIR-DWI (p=0.00001) and FBIR-DWI (p=0.000041). CONCLUSIONS TRIGIR-DWI may be the optimal acquisition of DWI for pancreatic cancer at 3.0T.
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Affiliation(s)
- Xiuzhong Yao
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Tiantao Kuang
- Department of General Surgery, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Li Wu
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Hao Feng
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Hao Liu
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Weizhong Cheng
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Shengxiang Rao
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - He Wang
- Global Applied Science Laboratory of GE Healthcare, No. 1, Huatuo Road, Zhangjiang Hi-tech Park, Pudong District, Shanghai 201203, China.
| | - Mengsu Zeng
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
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Jang KM, Kim SH, Lee SJ, Choi D. The value of gadoxetic acid-enhanced and diffusion-weighted MRI for prediction of grading of pancreatic neuroendocrine tumors. Acta Radiol 2014; 55:140-8. [PMID: 23897307 DOI: 10.1177/0284185113494982] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Parenchyma-preserving resection for the treatment of benign pancreatic neuroendocrine tumors (NETs) has been tried, and preoperative prediction of benign pancreatic NET is important. Recently, diffusion-weighted imaging (DWI) of abdomen magnetic resonance imaging (MRI) has been used to characterize benign and malignant tumors and DWI might be helpful in prediction of benign pancreatic NETs. PURPOSE To evaluate the value of gadoxetic acid-enhanced MRI and DWI in predicting benign pancreatic NETs for determination of parenchyma-preserving resection. MATERIAL AND METHODS Our ethics committee approved this study with a waiver of informed consent given its retrospective design. We searched radiology and pathology databases from November 2010 to July 2012 to identify patients who underwent surgery for pancreatic NETs (<4 cm). Twenty patients in the benign group and 14 patients in the non-benign group were included in this study. Two radiologists analyzed the morphologic features, signal intensity on MR images including DWI (b = 800), and dynamic enhancement pattern of the tumors with consensus. The tumor-to-parenchyma ratio and tumor apparent diffusion coefficients (ADCs) were quantitatively assessed. RESULTS The benign pancreatic NETs were more often round (7/20, 35%) or ovoid (13/20, 65%) in shape and less hypovascular on the arterial phase (3/20, 15%) than were the non-benign pancreatic NETs (1/14, 7.1% and 5/14, 35.8%; 7/14, 50% respectively; P < 0.05). Main pancreatic duct dilatation by tumors was demonstrated only in non-benign pancreatic NETs (4/14, 28.4%; P = 0.021). ADC values and ratios were significantly different between benign pancreatic NETs (mean, 1.48 × 10(-3 )mm(2)/sec, 1.11 ± 0.25, each) and non-benign pancreatic NETs (mean, 1.04 × 10(-3 )mm(2)/sec, 0.74 ± 0.13, each) (P < 0.01). Other qualitative and quantitative analyses between benign and non-benign pancreatic NETs were not significantly different (P > 0.05). CONCLUSION Abdominal MRI with DWI may be useful for differentiating benign pancreatic NETs from non-benign pancreatic NETs, which might be helpful for determination of parenchyma-preserving resection.
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Affiliation(s)
- Kyung Mi Jang
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Seong Hyun Kim
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Soon Jin Lee
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Dongil Choi
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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Ma C, Wang J, Li YJ, Pan CS, Zhang Y, Wang H, Chen SY, Lu JP. Comparisons of Image Quality and ADCs in Breath-Hold, Respiratory-Triggered and Free-Breathing DWI of Pancreas at 3-T. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/ojrad.2014.44037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Ye XH, Gao JY, Yang ZH, Liu Y. Apparent diffusion coefficient reproducibility of the pancreas measured at different MR scanners using diffusion-weighted imaging. J Magn Reson Imaging 2013; 40:1375-81. [PMID: 24222019 DOI: 10.1002/jmri.24492] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 10/07/2013] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To evaluate the reproducibility of the pancreatic apparent diffusion coefficient (ADC) measured at different MR scanners. MATERIALS AND METHODS Twenty-four healthy volunteers underwent three consecutive diffusion-weighted imaging (DWI) at a GE 1.5 Tesla (T), a Siemens 1.5 T and a Philips 3.0 T (session 1), and imaged again using the same protocol at the same GE 1.5 T (session 2) 12 days later. The ADC values of pancreas were measured at all three MR scanners. Paired-sample t-test and the Bland-Altman method were used for ADC data analysis. RESULTS The individual mean ADC values of pancreatic head, body, and tail (in 10(-3) mm(2)/s) measured at GE 1.5 T (2.24, 2.01, 1.88 for observer 1 and 2.23, 2.00, 1.92 for observer 2) and Siemens 1.5 T (2.24, 2.04, 1.84 for observer 1 and 2.20, 1.98, 1.84 for observer 2) were significantly higher than those at Philips 3.0 T (2.06, 1.80, 1.56 for observer 1 and 2.02, 1.79, 1.60 for observer 2) (P = 0.000-0.008). There was no significant difference of ADC values either between GE 1.5 T and Siemens 1.5 T (P = 0.115-0.966), or between imaging session 1 and 2 at GE 1.5 T (P = 0.072-0.938). The range of mean difference ± limits of agreement (in 10(-3) mm(2)/s) was -0.07-0.04 ± 0.39-0.53 between two 1.5 T scanners, and -0.04-0.04 ± 0.24-0.47 between two imaging sessions at GE 1.5 T. CONCLUSION The measured ADC values of pancreas are affected by the field strength of scanner, but show good reproducibility between different MR systems with same field strength and at the same MR system over time.
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Affiliation(s)
- Xiao-Hua Ye
- Department of Radiology, Beijing Hospital and the 5th Clinical School of Peking University, Beijing, China
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Agreement and reproducibility of apparent diffusion coefficient measurements of dual-b-value and multi-b-value diffusion-weighted magnetic resonance imaging at 1.5 Tesla in phantom and in soft tissues of the abdomen. J Comput Assist Tomogr 2013; 37:46-51. [PMID: 23321832 DOI: 10.1097/rct.0b013e3182720e07] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To compare the coefficient of variation (CV) and long-term reproducibility of apparent diffusion coefficient (ADC) in a simple fluid-filled phantom and abdominal organs simultaneously. MATERIALS AND METHODS Retrospective institutional review board-approved and Health Insurance Portability and Accountability Act-compliant study sequentially selected 100 patients who underwent clinically indicated abdominal magnetic resonance imaging. A subset of 58 patients had repeat scans within 2 to 5 months after the initial magnetic resonance imaging. Two diffusion-weighted imaging techniques (b-values 0-750 mm/s) were performed to compare the ADC values. Mean ADC values were calculated for 10 locations and the reference phantom. The CV and Bland-Altman plots were calculated for the phantom and soft tissues at each session and location. RESULTS There were no significant differences in the mean ADC values between repeated acquisitions. However, ADC values were statistically higher using dual-b-value than multi-b-value diffusion-weighted imaging. The CV for the phantom was 8.6 versus 10.8 for dual-b-value and multi-b-value, respectively. The CVs for the soft tissues had a wider range compared with that of the phantom (liver, 12.6 vs 9.0; spleen, 11.7 vs 11.2; gallbladder, 11.0 vs 13.6; head of pancreas, 14.6 vs 14.7; body of pancreas, 13.4 vs 13.0; tail of pancreas, 14.8 vs 16.3; right kidney, 9.1 vs 9.6; left kidney, 9.3 vs 9.3; right paraspinal muscle, 7.9 vs 7.5; left paraspinal muscle, 7.3 vs 7.3, respectively). CONCLUSIONS A change in ADC less than 11% falls into the range of measurement variability. Paraspinal muscle could potentially be used as an internal reference parameter.
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Jang KM, Kim SH, Lee SJ, Park HJ, Choi D, Hwang J. Added value of diffusion-weighted MR imaging in the diagnosis of ampullary carcinoma. Radiology 2013; 266:491-501. [PMID: 23238154 DOI: 10.1148/radiol.12121106] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
PURPOSE To evaluate the added value of diffusion-weighted magnetic resonance (MR) imaging in diagnostic performance of conventional MR imaging for diagnosis of ampullary carcinoma. MATERIALS AND METHODS This retrospective study was institutional review board approved, and informed consent was waived. Twenty-three patients with malignant ampullary obstruction and 39 patients with benign ampullary obstruction were included. Qualitative (signal intensity and enhancement pattern) and quantitative (apparent diffusion coefficient [ADC]) analyses were conducted for visible or expected locations of duodenal papillae. Two observers independently reviewed conventional MR images and subsequently reviewed combined conventional and diffusion-weighted MR images. A five-point scale for likelihood of ampullary carcinoma was used. Fisher exact test and Mann-Whitney U test were used for comparing groups, and diagnostic performance (receiver operating characteristic [ROC] curve analysis), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated. RESULTS Visible or expected duodenal papillae in benign group showed isointensity (27-38 of 39, 69%-97%) and similar enhancement pattern (27 of 39, 69%) to that of normal duodenal wall more frequently than in malignant group (seven to 18 of 23 [30%-78%] and three of 23 [13%], respectively) on conventional MR images (P < .05). On diffusion-weighted images, 21 of 23 (91%) ampullary carcinomas showed hyperintensity, whereas all benign cases showed isointensity compared with normal duodenal wall (P < .001). Mean ADC of ampullary carcinomas (1.23 × 10(-3) mm(2)/sec) was significantly lower than that of benign group (1.69 × 10(-3) mm(2)/sec) (P < .001). Diagnostic performance (area under ROC curve [Az]) of both observers improved significantly after additional review of diffusion-weighted images; Az improved from 0.923 to 0.992 (P = .029) for observer 1 and from 0.910 to 0.992 (P = .025) for observer 2. In addition, diagnostic accuracy, sensitivity, specificity, PPV, and NPV of combined conventional and diffusion-weighted MR images were higher than those of conventional MR images alone. CONCLUSION Addition of diffusion-weighted imaging to conventional MR imaging improves detection of ampullary carcinoma when compared with conventional MR imaging alone.
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Affiliation(s)
- Kyung Mi Jang
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, Korea
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Jang KM, Kim SH, Lee SJ, Park MJ, Lee MH, Choi D. Differentiation of an intrapancreatic accessory spleen from a small (<3-cm) solid pancreatic tumor: value of diffusion-weighted MR imaging. Radiology 2012; 266:159-67. [PMID: 23093681 DOI: 10.1148/radiol.12112765] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE To evaluate the value of diffusion-weighted (DW) imaging in differentiation of an intrapancreatic accessory spleen (IPAS) from a small (<3 cm) solid pancreatic tumor. MATERIALS AND METHODS This retrospective study was approved by the institutional review board, and informed consent was waived. Twenty patients with IPAS and 22 patients with small solid pancreatic tumors were included. All patients underwent abdominal magnetic resonance (MR) imaging with DW and gadoxetic acid-enhanced imaging. Qualitative (signal intensity) and quantitative (signal intensity and apparent diffusion coefficient [ADC]) evaluations were performed by two observers. Fisher exact test and Mann-Whitney U test were used for comparing groups. RESULTS Compared with the spleen, the IPAS showed isointensity more frequently than did small pancreatic tumors on T2-weighted images (95% [19 of 20] vs 41% [nine of 22]), arterial phase images (100% [20 of 20] vs 18% [four of 22]), portal phase images (100% [20 of 20] vs 23% [five of 22]), late phase images (100% [20 of 20] vs 41% [nine of 22]), and DW images with b value of 0 sec/mm(2) (100% [20 of 20] vs 9% [two of 22]), b value of 100 sec/mm(2) (95% [19 of 20] vs 27% [six of 22]), and b value of 800 sec/mm(2) (100% [20 of 20] vs 27% [six of 22]), with significant differences (P < .01). The means of the absolute value of relative signal intensity and ADC ratio on DW images of IPAS were significantly lower and closer to zero than those of pancreatic tumors (P < .05). Visual assessment of the similarity between pancreatic lesion and spleen on DW images for diagnosis of IPAS yielded diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 95% (40 of 42), 100% (20 of 20), 91% (20 of 22), 91% (20 of 22), and 100% (20 of 20), respectively, for observer 1 and 90% (38 of 42), 95% (19 of 20), 86% (19 of 22), 86% (19 of 22), and 95% (19of 20), respectively, for observer 2. CONCLUSION In addition to conventional morphologic MR imaging, DW imaging can be used as a tool for differentiating IPAS from solid pancreatic tumors. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12112765/-/DC1.
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Affiliation(s)
- Kyung Mi Jang
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710, Korea
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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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Mo YH, Jaw FS, Ho MC, Wang YC, Peng SSF. Hepatic ADC value correlates with cirrhotic severity of patients with biliary atresia. Eur J Radiol 2010; 80:e253-7. [PMID: 21123015 DOI: 10.1016/j.ejrad.2010.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 10/20/2010] [Accepted: 11/03/2010] [Indexed: 01/01/2023]
Abstract
INTRODUCTION At least 40% of survivors of biliary atresia have progressive cirrhosis even after undergoing Kasai operation. The values of hepatic apparent diffusion coefficient and apparent-diffusion-coefficient-related indices were applied to biliary atresia patients and correlated with cirrhotic severity scores of model for end-stage liver disease or pediatric end-stage liver disease model, Child-Turcotte, and Child-Pugh systems. MATERIALS AND METHODS Thirty-three biliary atresia patents (mean=1140, 61-4314 days of age) received magnetic resonance image examinations due to complications of biliary atresia from April 2008 to August 2009. Two non-breath-hold diffusion weighted imaging sequences were performed with motion-probing gradients in three directions with two b values: 0/100 and 0/500 s/mm2; 1000 ms/61.1 ms, time to repeat/time to echo; number of excitation, 1.0; 8 mm section thickness; 40 cm×40 cm field of view; 128×256 matrix in all biliary atresia patients and 18 control subjects. We used the Spearman rank correlation test to analyze the relationship among the scores of model for end-stage liver disease or pediatric end-stage liver disease model, Child-Turcotte and Child-Pugh scores and right hepatic apparent diffusion coefficients, apparent diffusion coefficient using b factor of 500-albumin product and alanine transaminase/apparent diffusion coefficient with b factor of 500 ratio. RESULTS The right hepatic apparent diffusion coefficient using b factor of 100, apparent diffusion coefficient with b factor of 500 and product of apparent diffusion coefficient with b factor of 500-albumin level were significantly negatively correlated (p≤0.0125) with model for end-stage liver disease or pediatric end-stage liver disease model, Child-Turcotte, and Child-Pugh scores of biliary atresia patients. The ratio of alanine transaminase level/right hepatic apparent diffusion coefficient with b factor of 500 was also significantly (p≤0.0251), moderately correlated with Child-Turcotte and Child-Pugh scores (rho=0.5256 and 0.7518, respectively). CONCLUSION Right hepatic apparent diffusion coefficient with b factor of 500 and alanine transaminase/right hepatic apparent diffusion coefficient with b factor of 500 can be useful for long-term follow-up of cirrhotic severity in biliary atresia patients.
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Affiliation(s)
- Yuan Heng Mo
- Institute of Biomedical Engineering, College of Engineering, National Taiwan University, and Department of Radiology, Cathay General Hospital, Taipei, Taiwan.
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