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Sample records for resonance imaging diffusion-weighted

  1. Diffusion-Weighted Magnetic Resonance Imaging in Renal Lesion Characterization

    Directory of Open Access Journals (Sweden)

    Elif Karadeli

    2012-03-01

    Conclusion: The technique has the advantage that it is non-invasive without need for gadolinium administration, takes about 2 minute. This method provides qualitative and quantitative infomation on tissue characterization. DA-MRI and ADC values are important for characterization of renal lesions. Especially, utility of diffusion-weighted magnetic resonance imaging in the patients with risk for nephrogenic systemic fibrosis (NSF could be beneficial. [Cukurova Med J 2012; 37(1: 27-36

  2. Diffusion-weighted magnetic resonance imaging of the abdomen

    International Nuclear Information System (INIS)

    Schmid-Tannwald, C.; Reiser, M.F.; Zech, C.J.

    2011-01-01

    Diffusion-weighted magnetic resonance imaging (DW-MRI) provides qualitative and quantitative information of tissue cellularity and the integrity of cellular membranes. Since DW-MRI can be performed without ionizing radiation exposure and contrast media application, DW-MRI is a particularly attractive tool for patients with allergies for gadolinium-based contrast agents or renal failure. Recent technical developments have made DW-MRI a robust and feasible technique for abdominal imaging. DW-MRI provides information on the detection and characterization of focal liver lesions and can also visualize treatment effects and early changes in chronic liver disease. In addition DW-MRI is a promising tool for the detection of inflammatory changes in patients with Crohn's disease. (orig.) [de

  3. Diffusion-weighted magnetic resonance imaging in autoimmune pancreatitis

    International Nuclear Information System (INIS)

    Taniguchi, Takao; Kobayashi, Hisato; Nishikawa, Koji; Iida, Etsushi; Michigami, Yoshihiro; Morimoto, Emiko; Yamashita, Rikiya; Miyagi, Ken; Okamoto, Motozumi

    2009-01-01

    The aim of this study was to investigate the usefulness of diffusion-weighted magnetic resonance imaging (DWI MRI) for the diagnosis and evaluation of autoimmune pancreatitis (AIP). A total of 4 consecutive patients with AIP, 5 patients with chronic alcoholic pancreatitis (CP), and 13 patients without pancreatic disease (controls) were studied. DWI was performed in the axial plane with spin-echo echo-planar imaging single-shot sequence. Apparent diffusion coefficients (ADCs) were measured in circular regions of interest in the pancreas. In AIP patients, abdominal MRI was performed before, and 2-4 weeks after steroid treatment. Follow-up study was performed chronologically for up to 11 months in two patients. The correlation between ADCs of the pancreas and the immunoglobulin G4 (IgG4) index (serum IgG4 value/serum IgG4 value before steroid treatment) was evaluated. In the AIP patients, DWI of the pancreas showed high signal intensity, and the ADCs of the pancreas (mean±standard deviation (SD): 0.97±0.18 x 10 -3 mm 2 /s) were significantly lower than those in patients with CP (1.45±0.10 x 10 -3 mm 2 /s) or the controls (1.45±0.16 x 10 -3 mm 2 /s) (Mann-Whitney U-test, P s =-0.80, P<0.05). Autoimmune pancreatitis showed high signal intensity on DWI, which improved after steroid treatment. ADCs reflected disease activity. Thus, diffusion-weighted MRI might be useful for diagnosing AIP, determining the affected area, and evaluating the effect of treatment. (author)

  4. Cerebral Fat Embolism: Diffusion-weighted Magnetic Resonance Imaging Findings

    International Nuclear Information System (INIS)

    Ryu, C.W.

    2005-01-01

    PURPOSE: To demonstrate the diffusion-weighted (DWI) magnetic resonance imaging (MRI) findings, and the follow-up MRI findings, of cerebral fat embolism in the acute stage. MATERIAL AND METHODS: The initial DWI and clinical findings of six patients with cerebral fat embolism were retrospectively evaluated. The finding of DWI with a b-value of 1000 s/mm 2 (b=1000) was compared with that of DWI with a b-value of 0 s/mm 2 (b=0). In three patients who underwent follow-up MRI, the interval change of the lesion on T2-weighted images was investigated. RESULTS: The characteristic DWI finding of cerebral fat embolism in the acute stage was multiple, hyperintense, dot-like lesions disseminated in the brain. These lesions were distributed dominantly in the bilateral border-zone areas. Some lesions had an ancillary location including the cortex, deep white matter, basal ganglia, and cerebellum. The lesions were more intense and numerous in DWI (b=1000) than in DWI (b=0). The findings on the follow-up T2-weighted images were multiple confluent hyperintense lesions in the white matter with progression since the initial MRI. CONCLUSION: DWI could be a sensitive tool for detecting cerebral fat embolism in the acute phase. It is recommended that DWI be included in the initial evaluation of cerebral fat embolism with MRI

  5. The role of diffusion weighted magnetic resonance imaging in ...

    African Journals Online (AJOL)

    Aim of the work: To demonstrate the role of Diffusion Weighted Imaging and ADC maps in assessing normal progression of the infantile brain myelination. Patients and methods: The present work included 30 infants with normal MRI study of the brain, normal psychomotor development and normal neurological examination.

  6. Diffusion-Weighted Magnetic Resonance Imaging in Rhombencephalitis due to Listeria monocytogenes

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    Hatipoglu, H.G.; Onbasioglu Gurbuz, M.; Sakman, B.; Yuksel, E. [Dept. of Radiology, Ankara Numune Education and Research Hospital, Ankara (Turkey)

    2007-04-15

    We present diffusion-weighted imaging findings of a case of rhombencephalitis due to Listeria monocytogenes. It is a rare, life-threatening disorder. The diagnosis is difficult by clinical findings only. In this report, we aim to draw attention to the role of conventional and diffusion-weighted magnetic resonance imaging findings. To our knowledge, this is the first case report in the literature with apparent diffusion coefficient values of diseased brain parenchyma.

  7. Role of diffusion-weighted magnetic resonance imaging in the diagnosis of extrahepatic cholangiocarcinoma

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To determine the clinical value of diffusion-weight- ed imaging (DWI) for the diagnosis of extrahepatic cholangiocarcinoma (EHCC) by comparing the diagnostic sensitivity of DWI and magnetic resonance cholan-giopancreatography (MRCP). METHODS: Magnetic resonance imaging examination was performed in 56 patients with suspected EHCC. T1- weighted imaging, T2-weighted imaging, MRCP and DWI sequence, DWI using single-shot spin-echo echoplanar imaging sequence with different b values (100, 300, 500, 800 and 1...

  8. Osteosarcoma subtypes: Magnetic resonance and quantitative diffusion weighted imaging criteria.

    Science.gov (United States)

    Zeitoun, Rania; Shokry, Ahmed M; Ahmed Khaleel, Sahar; Mogahed, Shaimaa M

    2018-03-01

    Osteosarcoma (OS) is a primary bone malignancy, characterized by spindle cells producing osteoid. The objective of this study is to describe the magnetic resonance imaging (MRI) features of different OS subtypes, record their attenuation diffusion coefficient (ADC) values and to point to the relation of their pathologic base and their corresponding ADC value. We performed a retrospective observational lesion-based analysis for 31 pathologically proven osteosarcoma subtypes: osteoblastic (n = 9), fibroblastic (n = 8), chondroblastic (n = 6), para-osteal (n = 3), periosteal (n = 1), telangiectatic (n = 2), small cell (n = 1) and extra-skeletal (n = 1). On conventional images we recorded: bone of origin, epicenter, intra-articular extension, and invasion of articulating bones, skip lesions, distant metastases, pathological fractures, ossified matrix, hemorrhage and necrosis. We measured the mean ADC value for each lesion. Among the included OS lesions, 51.6% originated at the femur, 29% showed intra-articular extension, 16% invaded neighboring bone, 9% were associated with pathological fracture and 25.8% were associated with distant metastases. On MRI, all lesions showed ossified matrix, 35.5% showed hemorrhage and 58% showed necrosis. The mean ADC values for OS lesions ranged from 0.74 × 10 -3  mm 2 /s (recorded for conventional osteoblastic OS) to 1.50 × 10 -3  mm 2 /s (recorded for telangiectatic OS) with an average value of 1.16 ± 0.18 × 10 -3  mm 2 /s. Conventional chondroblastic OS recorded higher values compared to the other two conventional subtypes. Osteosarcoma has different pathologic subtypes which correspondingly vary in their imaging criteria and their ADC values. Copyright © 2018. Production and hosting by Elsevier B.V.

  9. Diagnosis of pericardial cysts using diffusion weighted magnetic resonance imaging: A case series

    Directory of Open Access Journals (Sweden)

    Mousavi Negareh

    2011-09-01

    Full Text Available Abstract Introduction Congenital pericardial cysts are benign lesions that arise from the pericardium during embryonic development. The diagnosis is based on typical imaging features, but atypical locations and signal magnetic resonance imaging sequences make it difficult to exclude other lesions. Diffusion-weighted magnetic resonance imaging is a novel method that can be used to differentiate tissues based on their restriction to proton diffusion. Its use in differentiating pericardial cysts from other pericardial lesions has not yet been described. Case presentation We present three cases (a 51-year-old Caucasian woman, a 66-year-old Caucasian woman and a 77-year-old Caucasian woman with pericardial cysts evaluated with diffusion-weighted imaging using cardiac magnetic resonance imaging. Each lesion demonstrated a high apparent diffusion coefficient similar to that of free water. Conclusion This case series is the first attempt to investigate the utility of diffusion-weighted magnetic resonance imaging in the assessment of pericardial cysts. Diffusion-weighted imaging may be a useful noninvasive diagnostic tool for pericardial cysts when conventional imaging findings are inconclusive.

  10. Magnetic resonance imaging of epidermoid, including diffusion weighted images and an atypical case

    International Nuclear Information System (INIS)

    Takahashi, Shoki; Higano, Shuichi; Kurihara, Noriko

    1994-01-01

    In order to study the role of magnetic resonance imaging (MRI) in diagnosing intracranial epidermoid, we evaluated the MRI findings on five cases with such tumor, all of which were surgically verified. In addition to standard spin-echo (SE) images obtained in all cases, diffusion-weighted images were acquired in two patients. In four patients, the tumor revealed to be almost isointense relative to cerebrospinal fluid (CSF) on both T 1 -and T 2 -weighted images, while it tended to show slightly hyperintense to CSF on proton-density-weighted images; thus, based on the signal intensity on standard SE images the distinction between epidermoid and arachnoid cyst may be difficult. Furthermore, the presence of the tumor which has a tendency to grow in and along the subarachnoid space causing relatively minimal mass effect may be overlooked. Diffusion-weighted images were shown to have advantages in such cases by demonstrating the tumor unequivocally as a mass of high signal, and differentiating it from arachnoid cysts. In the remaining patient, its appearance was atypical, showing bright signal on both T 1 -and T 2 -weighted images. In conclusion free of bone artifacts, multiplanar MRI with additional diffusion-weighted images provides a clear demonstration of epidermoid, and its differentiation from arachnoid cyst, thus obviating the need for CT cisternography. (author)

  11. Cerebral Effects of Targeted Temperature Management Methods Assessed by Diffusion-Weighted Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Grejs, Anders Morten; Gjedsted, Jakob; Pedersen, Michael

    2016-01-01

    The aim of this randomized porcine study was to compare surface targeted temperature management (TTM) to endovascular TTM evaluated by cerebral diffusion-weighted magnetic resonance imaging (MRI): apparent diffusion coefficient (ADC), and by intracerebral/intramuscular microdialysis. It is well k...

  12. Value of diffusion weighted magnetic resonance imaging in the ...

    African Journals Online (AJOL)

    Ahmad Hafez Ahmad Alsayed Afifi

    2012-10-12

    DCE) ... nography, IVU, CT or any other imaging modality were checked. ... measuring the ADC value in different areas. The ROI is fitted ..... MR imaging of the prostate gland. PET. Clinics 2009;4(2):139–54. 14. Yu KK, Hricak H.

  13. Improving CT-guided transthoracic biopsy of mediastinal lesions by diffusion-weighted magnetic resonance imaging

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    Guimaraes, Marcos Duarte; TyngI, Chiang Cheng; Bitencourt, Almir Galvao Vieira; Gross, Jefferson Luiz; Zurstrassen, Charles Edouard, E-mail: marcosduarte500@gmail.com [AC Camargo Cancer Center, Sao Paulo, SP (Brazil); Hochhegger, Bruno [Universidade Federal de Ciencias da Saude de Porto Alegre (UFCSPA), RS (Brazil). Dept. de Radiologia; Benveniste, Marcelo Felipe Kuperman; Odisio, Bruno Calazans [University of Texas, MD Anderson Cancer Center, Houston, TX (United States); Marchiori, Edson [Universidade Federal do Rio de Janeiro (UFRJ), Petropolis, RJ (Brazil)

    2014-11-15

    Objectives: to evaluate the preliminary results obtained using diffusion-weighted magnetic resonance imaging and the apparent diffusion coefficient for planning computed tomography-guided biopsies of selected mediastinal lesions. Methods: eight patients with mediastinal lesions suspicious for malignancy were referred for computed tomography-guided biopsy. Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient measurement were performed to assist in biopsy planning with diffusion/computed tomography fused images. We selected mediastinal lesions that could provide discordant diagnoses depending on the biopsy site, including large heterogeneous masses, lesions associated with lung atelectasis or consolidation, lesions involving large mediastinal vessels and lesions for which the results of biopsy using other methods and histopathological examination were divergent from the clinical and radiological suspicion. Results: in all cases, the biopsy needle was successfully directed to areas of higher signal intensity on diffusion weighted sequences and the lowest apparent diffusion coefficient within the lesion (mean, 0.8 [range, 0.6–1.1]610{sup -3} mm{sup 2}/s), suggesting high cellularity. All biopsies provided adequate material for specific histopathological diagnoses of four lymphomas, two sarcomas and two thymoma s. Conclusion: functional imaging tools, such as diffusion-weighted imaging and the apparent diffusion coefficient, are promising for implementation in noninvasive and imaging-guided procedures. However, additional studies are needed to confirm that mediastinal biopsy can be improved with these techniques. (author)

  14. Diffusion-weighted magnetic resonance imaging of cerebral white matter development

    International Nuclear Information System (INIS)

    Prayer, Daniela.; Prayer, Lucas

    2003-01-01

    Diffusion-weighted magnetic resonance imaging (DWI) has become a sensitive tool to monitor white matter development. Different applications of diffusion-weighted techniques provide information about premyelinating, myelinating, and postmyelinating states of white matter maturation. Mirroring maturational processes on the cellular level, DWI has to be regarded as a morphological method as well as a functional instrument, giving insight into molecular processes during the formation of axons and myelin sheets and into the steric arrangement of white matter tracts the formation of which is strongly influenced by their function

  15. Diffusion-weighted magnetic resonance imaging of cerebral white matter development

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    Prayer, Daniela. E-mail: daniela.prayer@univie.ac.at; Prayer, Lucas

    2003-03-01

    Diffusion-weighted magnetic resonance imaging (DWI) has become a sensitive tool to monitor white matter development. Different applications of diffusion-weighted techniques provide information about premyelinating, myelinating, and postmyelinating states of white matter maturation. Mirroring maturational processes on the cellular level, DWI has to be regarded as a morphological method as well as a functional instrument, giving insight into molecular processes during the formation of axons and myelin sheets and into the steric arrangement of white matter tracts the formation of which is strongly influenced by their function.

  16. Acute vertebral fracture: differentiation of malignant and benign causes by diffusion weighted magnetic resonance imaging

    International Nuclear Information System (INIS)

    Mubarak, F.; Akhtar, W.

    2011-01-01

    Objective: To evaluate the sensitivity, specificity and accuracy of diffusion weighted (DWI) magnetic resonance imaging (MRI) in the diagnosis and differentiation between benign (osteoporotic/infectious) and malignant vertebral compression fractures in comparison with histology findings and clinical follow up. Methods: The study was conducted at the Radiology Department, Aga Khan University Hospital (AKUH) Karachi. It was a one year cross-sectional study from 01/01/2009 to 01/01/2010. Forty patients with sixty three vertebral compression fractures were included. Diffusion-weighted sequences and apparent diffusion coefficient (ADC) images on a 1.5 T MR scanner were obtained in all patients to identify the vertebral compression fracture along with benign and malignant causes. Imaging findings were compared with histopathologic results and clinical follow-up. Results: Diffusion-weighted MR imaging found to have, 92% sensitivity, 90% specificity and accuracy of 85% in differentiation of benign and malignant vertebral compression fracture while PPV and NPV were 78 % and 90% respectively. Conclusion: Diffusion weighted magnetic resonance imaging offers a safe, accurate and non invasive modality to differentiate between the benign and malignant vertebral compression fracture. (author)

  17. Novel diffusion-weighted magnetic resonance imaging findings in leptomeningeal carcinomatosis: a case report

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    Hu, Y.F.; Chang, F.C.; Hu, H.H.; Hsu, L.C. [Taipei Veterans General Hospital, Taiwan (China). Depts. of Internal Medicine and Radiology, and Neurological Inst.

    2006-12-15

    This report presents a rare case of leptomeningeal carcinomatosis initially presenting with mental impairment and rapidly progressing to coma without any history of malignancy. In addition to highlighting the diagnostic difficulties, the linear high signal intensity along the cortex on the diffusion-weighted imaging (DWI) sequence of magnetic resonance (MR) imaging was identified accidentally. High signal change in the corresponding areas was also noted on unenhanced fluid-attenuated inversion recovery (FLAIR) MR imaging, which may be a novel method of diagnosing leptomeningeal carcinomatosis, which should be studied further.

  18. Measuring Restriction Sizes Using Diffusion Weighted Magnetic Resonance Imaging: A Review

    Directory of Open Access Journals (Sweden)

    Melanie Martin

    2013-01-01

    Full Text Available This article reviews a new concept in magnetic resonance as applied to cellular and biological systems. Diffusion weighted magnetic resonance imaging can be used to infer information about restriction sizes of samples being measured. The measurements rely on the apparent diffusion coefficient changing with diffusion times as measurements move from restricted to free diffusion regimes. Pulsed gradient spin echo (PGSE measurements are limited in the ability to shorten diffusion times and thus are limited in restriction sizes which can be probed. Oscillating gradient spin echo (OGSE measurements could provide shorter diffusion times so smaller restriction sizes could be probed.

  19. Medulloblastoma: correlation among findings of conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy

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    Fonte, Mariana Vieira de Melo da; Otaduy, Maria Concepcion Garcia; Lucato, Leandro Tavares; Reed, Umbertina Conti; Leite, Claudia da Costa [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Inst. de Radiologia]. E-mail: mvmfonte@uol.com.br; Costa, Maria Olivia Rodrigues; Amaral, Raquel Portugal Guimaraes [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Dept. de Radiologia; Reed, Umbertina Conti [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Dept. de Neurologia; Rosemberg, Sergio [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Dept. de Patologia

    2008-11-15

    To correlate imaging findings of medulloblastomas at conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy, comparing them with data in the literature. Preoperative magnetic resonance imaging studies of nine pediatric patients with histologically confirmed medulloblastomas (eight desmoplastic medulloblastoma, and one giant cell medulloblastoma) were retrospectively reviewed, considering demographics as well as tumors characteristics such as localization, morphology, signal intensity, contrast-enhancement, dissemination, and diffusion-weighted imaging and spectroscopy findings. In most of cases the tumors were centered in the cerebellar vermis (77.8%), predominantly solid (88.9%), hypointense on T 1-weighted images and intermediate/hyperintense on T 2-FLAIR-weighted images, with heterogeneous enhancement (100%), tumor dissemination/extension (77.8%) and limited water molecule mobility (100%). Proton spectroscopy acquired with STEAM technique (n = 6) demonstrated decreased Na a / Cr ratio (83.3%) and increased Co/Cr (100%) and ml/Cr (66.7%) ratios; and with PRESS technique (n = 7) demonstrated lactate peak (57.1%). Macroscopic magnetic resonance imaging findings in association with biochemical features of medulloblastomas have been useful in the differentiation among the most frequent posterior fossa tumors. (author)

  20. Medulloblastoma: correlation among findings of conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Fonte, Mariana Vieira de Melo da; Otaduy, Maria Concepcion Garcia; Lucato, Leandro Tavares; Reed, Umbertina Conti; Leite, Claudia da Costa; Costa, Maria Olivia Rodrigues; Amaral, Raquel Portugal Guimaraes; Reed, Umbertina Conti; Rosemberg, Sergio

    2008-01-01

    To correlate imaging findings of medulloblastomas at conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy, comparing them with data in the literature. Preoperative magnetic resonance imaging studies of nine pediatric patients with histologically confirmed medulloblastomas (eight desmoplastic medulloblastoma, and one giant cell medulloblastoma) were retrospectively reviewed, considering demographics as well as tumors characteristics such as localization, morphology, signal intensity, contrast-enhancement, dissemination, and diffusion-weighted imaging and spectroscopy findings. In most of cases the tumors were centered in the cerebellar vermis (77.8%), predominantly solid (88.9%), hypointense on T 1-weighted images and intermediate/hyperintense on T 2-FLAIR-weighted images, with heterogeneous enhancement (100%), tumor dissemination/extension (77.8%) and limited water molecule mobility (100%). Proton spectroscopy acquired with STEAM technique (n = 6) demonstrated decreased Na a / Cr ratio (83.3%) and increased Co/Cr (100%) and ml/Cr (66.7%) ratios; and with PRESS technique (n = 7) demonstrated lactate peak (57.1%). Macroscopic magnetic resonance imaging findings in association with biochemical features of medulloblastomas have been useful in the differentiation among the most frequent posterior fossa tumors. (author)

  1. Diffusion-weighted magnetic resonance imaging in the prostate transition zone: histopathological validation using magnetic resonance-guided biopsy specimens

    NARCIS (Netherlands)

    Hoeks, C.M.A.; Vos, E.K.; Bomers, J.G.R.; Barentsz, J.O.; Kaa, C.A. van de; Scheenen, T.W.J.

    2013-01-01

    OBJECTIVES: The objective of this study was to evaluate the apparent diffusion coefficient (ADC) of diffusion-weighted magnetic resonance (MR) imaging for the differentiation of transition zone cancer from non-cancerous transition zone with and without prostatitis and for the differentiation of

  2. Diffusion-Weighted Magnetic Resonance Imaging in Monitoring Rectal Cancer Response to Neoadjuvant Chemoradiotherapy

    International Nuclear Information System (INIS)

    Barbaro, Brunella; Vitale, Renata; Valentini, Vincenzo; Illuminati, Sonia; Vecchio, Fabio M.; Rizzo, Gianluca; Gambacorta, Maria Antonietta; Coco, Claudio; Crucitti, Antonio; Persiani, Roberto; Sofo, Luigi; Bonomo, Lorenzo

    2012-01-01

    Purpose: To prospectively monitor the response in patients with locally advanced nonmucinous rectal cancer after chemoradiotherapy (CRT) using diffusion-weighted magnetic resonance imaging. The histopathologic finding was the reference standard. Methods and Materials: The institutional review board approved the present study. A total of 62 patients (43 men and 19 women; mean age, 64 years; range, 28–83) provided informed consent. T 2 - and diffusion-weighted magnetic resonance imaging scans (b value, 0 and 1,000 mm 2 /s) were acquired before, during (mean 12 days), and 6–8 weeks after CRT. We compared the median apparent diffusion coefficients (ADCs) between responders and nonresponders and examined the associations with the Mandard tumor regression grade (TRG). The postoperative nodal status (ypN) was evaluated. The Mann-Whitney/Wilcoxon two-sample test was used to evaluate the relationships among the pretherapy ADCs, extramural vascular invasion, early percentage of increases in ADCs, and preoperative ADCs. Results: Low pretreatment ADCs ( −3 mm 2 /s) were correlated with TRG 4 scores (p = .0011) and associated to extramural vascular invasion with ypN+ (85.7% positive predictive value for ypN+). During treatment, the mean percentage of increase in tumor ADC was significantly greater in the responders than in the nonresponders (p 23% ADC increase had a 96.3% negative predictive value for TRG 4. In 9 of 16 complete responders, CRT-related tumor downsizing prevented ADC evaluations. The preoperative ADCs were significantly different (p = .0012) between the patients with and without downstaging (preoperative ADC ≥1.4 × 10 −3 mm 2 /s showed a positive and negative predictive value of 78.9% and 61.8%, respectively, for response assessment). The TRG 1 and TRG 2–4 groups were not significantly different. Conclusion: Diffusion-weighted magnetic resonance imaging seems to be a promising tool for monitoring the response to CRT.

  3. Diffusion-weighted magnetic resonance imaging in monitoring rectal cancer response to neoadjuvant chemoradiotherapy.

    Science.gov (United States)

    Barbaro, Brunella; Vitale, Renata; Valentini, Vincenzo; Illuminati, Sonia; Vecchio, Fabio M; Rizzo, Gianluca; Gambacorta, Maria Antonietta; Coco, Claudio; Crucitti, Antonio; Persiani, Roberto; Sofo, Luigi; Bonomo, Lorenzo

    2012-06-01

    To prospectively monitor the response in patients with locally advanced nonmucinous rectal cancer after chemoradiotherapy (CRT) using diffusion-weighted magnetic resonance imaging. The histopathologic finding was the reference standard. The institutional review board approved the present study. A total of 62 patients (43 men and 19 women; mean age, 64 years; range, 28-83) provided informed consent. T(2)- and diffusion-weighted magnetic resonance imaging scans (b value, 0 and 1,000 mm(2)/s) were acquired before, during (mean 12 days), and 6-8 weeks after CRT. We compared the median apparent diffusion coefficients (ADCs) between responders and nonresponders and examined the associations with the Mandard tumor regression grade (TRG). The postoperative nodal status (ypN) was evaluated. The Mann-Whitney/Wilcoxon two-sample test was used to evaluate the relationships among the pretherapy ADCs, extramural vascular invasion, early percentage of increases in ADCs, and preoperative ADCs. Low pretreatment ADCs (23% ADC increase had a 96.3% negative predictive value for TRG 4. In 9 of 16 complete responders, CRT-related tumor downsizing prevented ADC evaluations. The preoperative ADCs were significantly different (p = .0012) between the patients with and without downstaging (preoperative ADC ≥1.4 × 10(-3)mm(2)/s showed a positive and negative predictive value of 78.9% and 61.8%, respectively, for response assessment). The TRG 1 and TRG 2-4 groups were not significantly different. Diffusion-weighted magnetic resonance imaging seems to be a promising tool for monitoring the response to CRT. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Clinical application of diffusion-weighted magnetic resonance imaging to intracranial disorders

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    Yanaka, Kiyoyuki; Shirai, Shizuo; Kimura, Hiroshi [Soujinkai Hospital, Ibaraki (Japan); Kamezaki, Takao; Matsumura, Akira; Nose, Tadao

    1995-09-01

    Diffusion-weighted magnetic resonance imaging was performed to determine the changes in water diffusion and to investigate the detectability of diffusion anisotropy in patients with intracranial disorders. Diffusion maps of the apparent diffusion coefficient (ADC) were created of 19 patients with cerebral infarction, five with intracerebral hematoma, four with glioma, four with meningioma, four with hydrocephalus, and five with subdural hematoma. ADC was increased in chronic cerebral infarction and glioma, and decreased in acute cerebral infarction, meningioma, and the marginal area of glioma compared with the ADC of the normal gray matter. There was a significant difference in ADC between the marginal and internal areas of glioma. Increased ADC may be due to increased vasogenic edema in infarction and a lack of significant restriction of diffusion within glioma. Decreased ADC can be attributed to restricted diffusion caused by cytotoxic edema in infarction and the underlying histological pattern of densely packed tumor cells in glioma. Diffusion anisotropy of the internal capsule was less detectable in pathological than normal hemispheres. Diffusion anisotropy was less detectable in patients with hydrocephalus and subdural hematoma. Intracranial lesions were thought to have influenced the compression of the brain structures and cells, resulting in decreased diffusion. The measurement of ADC by diffusion-weighted magnetic resonance imaging has the potential for greater understanding of the biophysical changes in various intracranial disorders, including correct diagnosis of cerebral infarction, and histological diagnosis of brain tumor. (author).

  5. Abnormalities on diffusion-weighted magnetic resonance imaging in patients with transient ischemic attack

    International Nuclear Information System (INIS)

    Nakamura, Tomomi; Shibagaki, Yasuro; Uchiyama, Shinichiro; Iwata, Makoto

    2003-01-01

    We studied abnormalities on diffusion-weighted magnetic resonance imaging (DWI) in patients with transient ischemic attack (TIA). Out of 18 consecutive TIA patients, 9 patients had relevant focal abnormalities on DWI. Among TIA patients, six patients were associated with atrial fibrillation (Af), and all of these patients had focal abnormalities on DWI as well. TIA patients with Af had significantly more frequent focal abnormalities on DWI than those without Af (p=0.009; Fisher's exact probability test). In addition, the duration of TIA symptoms was not related to the presence of focal abnormalities on DWI. These results indicate that embolic mechanism may cause focal abnormalities on DWI. DWI was more sensitive to detect responsible ischemic lesions in these patients than T2-weighted image or fluid-attenuated inversion recovery image. (author)

  6. Abnormalities on diffusion-weighted magnetic resonance imaging in patients with transient ischemic attack

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Tomomi; Shibagaki, Yasuro [Ushiku Aiwa General Hospital, Ibaraki (Japan); Uchiyama, Shinichiro; Iwata, Makoto [Tokyo Women' s Medical Coll. (Japan)

    2003-03-01

    We studied abnormalities on diffusion-weighted magnetic resonance imaging (DWI) in patients with transient ischemic attack (TIA). Out of 18 consecutive TIA patients, 9 patients had relevant focal abnormalities on DWI. Among TIA patients, six patients were associated with atrial fibrillation (Af), and all of these patients had focal abnormalities on DWI as well. TIA patients with Af had significantly more frequent focal abnormalities on DWI than those without Af (p=0.009; Fisher's exact probability test). In addition, the duration of TIA symptoms was not related to the presence of focal abnormalities on DWI. These results indicate that embolic mechanism may cause focal abnormalities on DWI. DWI was more sensitive to detect responsible ischemic lesions in these patients than T2-weighted image or fluid-attenuated inversion recovery image. (author)

  7. Diffusion-weighted magnetic resonance imaging of symptomatic nerve root of patients with lumbar disk herniation

    International Nuclear Information System (INIS)

    Eguchi, Yawara; Ohtori, Seiji; Yamashita, Masaomi; Yamauchi, Kazuyo; Suzuki, Munetaka; Orita, Sumihisa; Kamoda, Hiroto; Arai, Gen; Ishikawa, Tetsuhiro; Miyagi, Masayuki; Ochiai, Nobuyasu; Kishida, Shunji; Inoue, Gen; Takahashi, Kazuhisa; Masuda, Yoshitada; Ochi, Shigehiro; Kikawa, Takashi; Toyone, Tomoaki; Takaso, Masashi; Aoki, Yasuchika

    2011-01-01

    Diffusion-weighted imaging (DWI) can provide valuable structural information that may be useful for evaluating pathological changes of the lumbar nerve root. Diffusion-weighted magnetic resonance (MR) neurography has recently been introduced as an alternative way to visualize nerves, but to date, quantitative DWI and MR neurography have not been applied to evaluate the pathology of lumbar nerve roots. Our purpose was to visualize lumbar nerve roots and to analyze their morphology by MR neurography, and to measure the apparent diffusion coefficient (ADC) of lumbar nerve roots compressed by herniated disks using 1.5-T MR imaging. Ten consecutive patients (median age, 48.0 and range, 20-72 years) with monoradicular symptoms caused by a lumbar herniated disk and 14 healthy volunteers were studied. Regions of interests were placed on the lumbar roots at dorsal root ganglia (DRG) and distal spinal nerves on DWI to quantify mean ADC values. The spinal nerve roots were also visualized by MR neurography. In the patients, mean ADC values were significantly greater in the compressed DRG and distal spinal nerves than in intact nerves. MR neurography also showed abnormalities such as nerve swelling at and below the compression in the symptomatic nerve root. Increased ADC values were considered to be because of edema and Wallerian degeneration of compressed nerve roots. DWI is a potential tool for analysis of the pathophysiology of lumbar nerve roots compressed by herniated disks. (orig.)

  8. Diffusion-weighted magnetic resonance imaging of symptomatic nerve root of patients with lumbar disk herniation

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Yawara; Ohtori, Seiji; Yamashita, Masaomi; Yamauchi, Kazuyo; Suzuki, Munetaka; Orita, Sumihisa; Kamoda, Hiroto; Arai, Gen; Ishikawa, Tetsuhiro; Miyagi, Masayuki; Ochiai, Nobuyasu; Kishida, Shunji; Inoue, Gen; Takahashi, Kazuhisa [Chiba University, Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba (Japan); Masuda, Yoshitada; Ochi, Shigehiro; Kikawa, Takashi [Chiba University Hospital, Department of Radiology, Chiba (Japan); Toyone, Tomoaki [Teikyo University Chiba Medical Center, Department of Orthopaedic Surgery, Chiba (Japan); Takaso, Masashi [Kitasato University, Department of Orthopaedic Surgery, School of Medicine, Sagamihara City, Kanagawa (Japan); Aoki, Yasuchika [Chiba Rosai Hospital, Department of Orthopedic Surgery, Ichihara, Chiba (Japan)

    2011-09-15

    Diffusion-weighted imaging (DWI) can provide valuable structural information that may be useful for evaluating pathological changes of the lumbar nerve root. Diffusion-weighted magnetic resonance (MR) neurography has recently been introduced as an alternative way to visualize nerves, but to date, quantitative DWI and MR neurography have not been applied to evaluate the pathology of lumbar nerve roots. Our purpose was to visualize lumbar nerve roots and to analyze their morphology by MR neurography, and to measure the apparent diffusion coefficient (ADC) of lumbar nerve roots compressed by herniated disks using 1.5-T MR imaging. Ten consecutive patients (median age, 48.0 and range, 20-72 years) with monoradicular symptoms caused by a lumbar herniated disk and 14 healthy volunteers were studied. Regions of interests were placed on the lumbar roots at dorsal root ganglia (DRG) and distal spinal nerves on DWI to quantify mean ADC values. The spinal nerve roots were also visualized by MR neurography. In the patients, mean ADC values were significantly greater in the compressed DRG and distal spinal nerves than in intact nerves. MR neurography also showed abnormalities such as nerve swelling at and below the compression in the symptomatic nerve root. Increased ADC values were considered to be because of edema and Wallerian degeneration of compressed nerve roots. DWI is a potential tool for analysis of the pathophysiology of lumbar nerve roots compressed by herniated disks. (orig.)

  9. The use of diffusion-weighted magnetic resonance imaging in the differentiation between benign and malignant breast lesions

    International Nuclear Information System (INIS)

    Pereira, Fernanda Philadelpho Arantes; Martins, Gabriela; Domingues, Marisa Nassar Aidar; Domingues, Romeu Cortes; Figueiredo, Eduardo; Fonseca, Lea Mirian Barbosa da

    2009-01-01

    Objective: to study the utility of diffusion-weighted magnetic resonance imaging in the differentiation between benign and malignant breast lesions. Materials and methods: forty-five women (mean age, 46.1 years) with 52 focal breast lesions underwent diffusion-weighted magnetic resonance imaging. The calculation of apparent diffusion coefficient (ADC) was based on the ADC map reflecting five b values (0, 250, 500, 750, and 1000 s/mm 2 ). The mean ADC value of each lesion was correlated with imaging findings and histopathologic results. Cutoff ADC, sensitivity and specificity of diffusion-weighted imaging in the differentiation between benign and malignant lesions were calculated. P -3 mm 2 /s) as compared with benign lesions (1.50 ± 0.34 x 10 -3 mm 2 /s) (P < 0.0001). Diffusion-weighted imaging showed high sensitivity and specificity (both, 92.3%) in the differentiation between benign and malignant lesions. Conclusion: diffusion-weighted imaging is a potential resource as an adjuvant to breast magnetic resonance imaging to differentiate benign from malignant lesions. Such sequence can be easily added to the standard breast magnetic resonance imaging protocol, without implying any significant increase in examination time. (author)

  10. The use of diffusion-weighted magnetic resonance imaging in the differentiation between benign and malignant breast lesions

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Fernanda Philadelpho Arantes; Martins, Gabriela; Domingues, Marisa Nassar Aidar; Domingues, Romeu Cortes [Clinica de Diagnostico por Imagem (CDPI), Rio de Janeiro, RJ (Brazil)], e-mail: fephila@gmail.com; Figueiredo, Eduardo [GE Healthcare, Sao Paulo, SP (Brazil); Fonseca, Lea Mirian Barbosa da [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Faculdade de Medicina

    2009-09-15

    Objective: to study the utility of diffusion-weighted magnetic resonance imaging in the differentiation between benign and malignant breast lesions. Materials and methods: forty-five women (mean age, 46.1 years) with 52 focal breast lesions underwent diffusion-weighted magnetic resonance imaging. The calculation of apparent diffusion coefficient (ADC) was based on the ADC map reflecting five b values (0, 250, 500, 750, and 1000 s/mm{sup 2}). The mean ADC value of each lesion was correlated with imaging findings and histopathologic results. Cutoff ADC, sensitivity and specificity of diffusion-weighted imaging in the differentiation between benign and malignant lesions were calculated. P < 0.05 was considered as statistically significant. Results: the mean ADC was significantly lower for malignant lesions (0.92 {+-} 0.26 x 10{sup -3} mm{sup 2}/s) as compared with benign lesions (1.50 {+-} 0.34 x 10{sup -3} mm{sup 2}/s) (P < 0.0001). Diffusion-weighted imaging showed high sensitivity and specificity (both, 92.3%) in the differentiation between benign and malignant lesions. Conclusion: diffusion-weighted imaging is a potential resource as an adjuvant to breast magnetic resonance imaging to differentiate benign from malignant lesions. Such sequence can be easily added to the standard breast magnetic resonance imaging protocol, without implying any significant increase in examination time. (author)

  11. Diffusion-weighted magnetic resonance imaging in carotid angioplasty and stenting with balloon embolic protection devices

    International Nuclear Information System (INIS)

    Asakura, Fumio; Kawaguchi, Kenji; Sakaida, Hiroshi; Toma, Naoki; Matsushima, Satoshi; Kuraishi, Keita; Tanemura, Hiroshi; Miura, Yoichi; Taki, Waro; Maeda, Masayuki

    2006-01-01

    We compared the results of two procedures to protect against distal embolism caused by embolic debris from carotid angioplasty with stent deployment (CAS) using diffusion-weighted magnetic resonance imaging (MRI). The study group comprised 39 men and 3 women (42 and 3 CAS procedures, respectively) with severe carotid stenosis (average age 70.0±6.6 years). During 20 CAS procedures the internal carotid artery was protected with a single balloon. A PercuSurge GuardWire was used for temporary occlusion. During 25 CAS procedures the internal and external carotid arteries were simultaneously temporarily occluded with a PercuSurge GuardWire and a Sentry balloon catheter, respectively. Diffusion-weighted MRI was performed 1 to 3 days after CAS. Data from 26 patients undergoing conventional angiography for diagnosis of cerebral ischemic disease, cerebral aneurysm or brain tumors were included as controls. Diffusion-weighted MRI after conventional diagnostic angiography showed ischemic spots in 3 of the 26 controls (11.5%). Ischemic spots were observed during 11 of 20 CAS procedures with the internal carotid artery protected with a single balloon (55.0%), and were observed during 9 of 25 CAS procedures with both the internal and external carotid arteries protected (36.0%). This difference was significant (P=0.0068). Ischemic lesions appeared not only ipsilateral to the carotid stenosis but also in the contralateral carotid artery (31.9%) and vertebrobasilar territory (25.3%). Better protection was obtained with simultaneous double occlusion of both the internal and external carotid artery than with single protection of the internal carotid artery during CAS. (orig.)

  12. Diffusion-Weighted Magnetic Resonance Imaging in Monitoring Rectal Cancer Response to Neoadjuvant Chemoradiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Barbaro, Brunella, E-mail: bbarbaro@rm.unicatt.it [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Vitale, Renata; Valentini, Vincenzo; Illuminati, Sonia [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Vecchio, Fabio M. [Department of Pathology, Catholic University School of Medicine, Rome (Italy); Rizzo, Gianluca [Department of Surgery, Catholic University School of Medicine, Rome (Italy); Gambacorta, Maria Antonietta [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy); Coco, Claudio; Crucitti, Antonio; Persiani, Roberto; Sofo, Luigi [Department of Surgery, Catholic University School of Medicine, Rome (Italy); Bonomo, Lorenzo [Department of Bioimaging and Radiological Sciences, Catholic University School of Medicine, Rome (Italy)

    2012-06-01

    Purpose: To prospectively monitor the response in patients with locally advanced nonmucinous rectal cancer after chemoradiotherapy (CRT) using diffusion-weighted magnetic resonance imaging. The histopathologic finding was the reference standard. Methods and Materials: The institutional review board approved the present study. A total of 62 patients (43 men and 19 women; mean age, 64 years; range, 28-83) provided informed consent. T{sub 2}- and diffusion-weighted magnetic resonance imaging scans (b value, 0 and 1,000 mm{sup 2}/s) were acquired before, during (mean 12 days), and 6-8 weeks after CRT. We compared the median apparent diffusion coefficients (ADCs) between responders and nonresponders and examined the associations with the Mandard tumor regression grade (TRG). The postoperative nodal status (ypN) was evaluated. The Mann-Whitney/Wilcoxon two-sample test was used to evaluate the relationships among the pretherapy ADCs, extramural vascular invasion, early percentage of increases in ADCs, and preoperative ADCs. Results: Low pretreatment ADCs (<1.0 Multiplication-Sign 10{sup -3}mm{sup 2}/s) were correlated with TRG 4 scores (p = .0011) and associated to extramural vascular invasion with ypN+ (85.7% positive predictive value for ypN+). During treatment, the mean percentage of increase in tumor ADC was significantly greater in the responders than in the nonresponders (p < .0001) and a >23% ADC increase had a 96.3% negative predictive value for TRG 4. In 9 of 16 complete responders, CRT-related tumor downsizing prevented ADC evaluations. The preoperative ADCs were significantly different (p = .0012) between the patients with and without downstaging (preoperative ADC {>=}1.4 Multiplication-Sign 10{sup -3}mm{sup 2}/s showed a positive and negative predictive value of 78.9% and 61.8%, respectively, for response assessment). The TRG 1 and TRG 2-4 groups were not significantly different. Conclusion: Diffusion-weighted magnetic resonance imaging seems to be a promising

  13. Rosai-Dorfman Disease with Epidural and Spinal Bone Marrow Involvement: Magnetic Resonance Imaging and Diffusion-Weighted Imaging Features

    International Nuclear Information System (INIS)

    Oner, A.Y.; Akpek, S.; Tali, T.

    2007-01-01

    Sinus histiocytosis with massive lymphadenopathy (SHML), or Rosai-Dorfman disease, is a rare histiocytic disorder that typically presents with chronic, self-limiting cervical lymphadenopathy. Although this disease mainly affects histiocytes, there are a few reports of bone marrow infiltration. Diffusion-weighted imaging (DWI) is a promising technology in differentiating between various bone marrow pathologies. We here present conventional magnetic resonance imaging and DWI features of a patient with SHML and bone marrow involvement

  14. Rosai-Dorfman Disease with Epidural and Spinal Bone Marrow Involvement: Magnetic Resonance Imaging and Diffusion-Weighted Imaging Features

    Energy Technology Data Exchange (ETDEWEB)

    Oner, A.Y.; Akpek, S.; Tali, T. [Dept. of Radiology, Gazi Univ. School of Medicine. Besevler-Ankara (Turkey)

    2007-04-15

    Sinus histiocytosis with massive lymphadenopathy (SHML), or Rosai-Dorfman disease, is a rare histiocytic disorder that typically presents with chronic, self-limiting cervical lymphadenopathy. Although this disease mainly affects histiocytes, there are a few reports of bone marrow infiltration. Diffusion-weighted imaging (DWI) is a promising technology in differentiating between various bone marrow pathologies. We here present conventional magnetic resonance imaging and DWI features of a patient with SHML and bone marrow involvement.

  15. Transient global amnesia: increased signal intensity in the right hippocampus on diffusion-weighted magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, M.; Sakamoto, S.; Ishii, K. [Division of Neuroimaging Research, Hyogo Institute for Aging Brain and Cognitive Disorders (Japan); Imamura, T.; Kazui, H.; Mori, E. [Division of Clinical Neurosciences, Hyogo Institute for Aging Brain and Cognitive Disorders, Hyogo (Japan)

    2002-03-01

    We report on a patient with pure transient global amnesia (TGA) whose magnetic resonance imaging (MRI) demonstrated a small region of increased signal intensity in the right hippocampus on diffusion-weighted imaging (DWI). DWI was sensitive and useful for evaluating the early stage of TGA and might help to explain the pathophysiology of TGA. (orig.)

  16. Transient global amnesia: increased signal intensity in the right hippocampus on diffusion-weighted magnetic resonance imaging

    International Nuclear Information System (INIS)

    Matsui, M.; Sakamoto, S.; Ishii, K.; Imamura, T.; Kazui, H.; Mori, E.

    2002-01-01

    We report on a patient with pure transient global amnesia (TGA) whose magnetic resonance imaging (MRI) demonstrated a small region of increased signal intensity in the right hippocampus on diffusion-weighted imaging (DWI). DWI was sensitive and useful for evaluating the early stage of TGA and might help to explain the pathophysiology of TGA. (orig.)

  17. Diffusion-Weighted Magnetic Resonance Imaging as a Cancer Biomarker: Consensus and Recommendations

    Directory of Open Access Journals (Sweden)

    Anwar R. Padhani

    2009-02-01

    Full Text Available On May 3, 2008, a National Cancer Institute (NCI-sponsored open consensus conference was held in Toronto, Ontario, Canada, during the 2008 International Society for Magnetic Resonance in Medicine Meeting. Approximately 100 experts and stakeholders summarized the current understanding of diffusion-weighted magnetic resonance imaging (DW-MRI and reached consensus on the use of DW-MRI as a cancer imaging biomarker. DW-MRI should be tested as an imaging biomarker in the context of well-defined clinical trials, by adding DW-MRI to existing NCI-sponsored trials, particularly those with tissue sampling or survival indicators. Where possible, DW-MRI measurements should be compared with histologic indices including cellularity and tissue response. There is a need for tissue equivalent diffusivity phantoms; meanwhile, simple fluid-filled phantoms should be used. Monoexponential assessments of apparent diffusion coefficient values should use two b values (> 100 and between 500 and 1000 mm2/sec depending on the application. Free breathing with multiple acquisitions is superior to complex gating techniques. Baseline patient reproducibility studies should be part of study designs. Both region of interest and histogram analysis of apparent diffusion coefficient measurements should be obtained. Standards for measurement, analysis, and display are needed. Annotated data from validation studies (along with outcome measures should be made publicly available. Magnetic resonance imaging vendors should be engaged in this process. The NCI should establish a task force of experts (physicists, radiologists, and oncologists to plan, organize technical aspects, and conduct pilot trials. The American College of Radiology Imaging Network infrastructure may be suitable for these purposes. There is an extraordinary opportunity for DW-MRI to evolve into a clinically valuable imaging tool, potentially important for drug development.

  18. Diffusion weighted magnetic resonance imaging: ischemic and traumatic injury of the central nervous system

    International Nuclear Information System (INIS)

    Huisman, T.A.G.M.; Sorensen, A.G.; Hawighorst, H.; Benoit, C.H.

    2001-01-01

    Diffusion weighted magnetic resonance imaging (DWI) represents a recent development that extends imaging from the depiction of the neuroanatomy into the field of functional and physiologic processes. DWI measures a fundamentally different physiologic parameter than conventional MRI. Image contrast is related to differences in the microscopic motion (diffusion) of water molecules within brain tissue rather than a change in total tissue water. Consequently, DWI can reveal pathology where conventional T1- and T2-weighted MR images are negative. DWI has clinically proven its value in the assessment of acute cerebral stroke and trauma by showing cerebral injury early due to its ability to discriminate between lesions with cytotoxic edema (decreased diffusion) from lesions with vasogenic edema (increased diffusion). Full tensor DWI allows to calculate a variety of functional maps, the most widely used maps include maps of apparent diffusion coefficients and isotropic diffusion. In addition maps of anisotropic diffusion can be calculated which are believed to give information about the integrity and location of fiber tracts. This functional-anatomical information will most probably play an increasingly important role in the early detection of primary and secondary tissue injury from various reasons and could guide and validate current and future neuroprotective treatments. (orig.) [de

  19. Tensor Based Representation and Analysis of Diffusion-Weighted Magnetic Resonance Images

    Science.gov (United States)

    Barmpoutis, Angelos

    2009-01-01

    Cartesian tensor bases have been widely used to model spherical functions. In medical imaging, tensors of various orders can approximate the diffusivity function at each voxel of a diffusion-weighted MRI data set. This approximation produces tensor-valued datasets that contain information about the underlying local structure of the scanned tissue.…

  20. Diffusion-weighted magnetic resonance imaging of the abdomen; Diffusionsgewichtete Magnetresonanztomographie des Abdomens

    Energy Technology Data Exchange (ETDEWEB)

    Schmid-Tannwald, C.; Reiser, M.F.; Zech, C.J. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

    2011-03-15

    Diffusion-weighted magnetic resonance imaging (DW-MRI) provides qualitative and quantitative information of tissue cellularity and the integrity of cellular membranes. Since DW-MRI can be performed without ionizing radiation exposure and contrast media application, DW-MRI is a particularly attractive tool for patients with allergies for gadolinium-based contrast agents or renal failure. Recent technical developments have made DW-MRI a robust and feasible technique for abdominal imaging. DW-MRI provides information on the detection and characterization of focal liver lesions and can also visualize treatment effects and early changes in chronic liver disease. In addition DW-MRI is a promising tool for the detection of inflammatory changes in patients with Crohn's disease. (orig.) [German] Die diffusionsgewichtete (DW-)MRT ermoeglicht die Erfassung qualitativer und quantitativer Informationen bzgl. der Gewebezellularitaet und Membranintegritaet. Die DW-MRT ist insbesondere bei Patienten mit einer Allergie gegen gadoliniumhaltige Kontrastmittel oder eingeschraenkter Nierenfunktion attraktiv, da ihr Einsatz nicht mit Strahlenexposition oder Kontrastmittelgabe verbunden ist. Durch technische Weiterentwicklungen ist die robuste Anwendung der DW-MRI in der Bildgebung des Abdomens seit einiger Zeit moeglich geworden. In der Leberdiagnostik lassen sich Zusatzinformationen zur Detektion und Charakterisierung von Leberlaesionen gewinnen, aber auch Therapieerfolge dokumentieren und fruehe chronische Leberveraenderungen visualisieren. Neben ihrer Rolle bei hepatologischen und onkologischen Fragestellungen erscheint der Einsatz der DW-MRT zudem bei entzuendlichen Fragestellungen wie dem Morbus Crohn sehr viel versprechend. (orig.)

  1. A semi-quantitative study of transient ischemic attacks by diffusion weighted magnetic resonance imaging

    International Nuclear Information System (INIS)

    Wen Feng; Guo Liang

    2007-01-01

    Objective: To explore the incidence and morphological findings of transient ischemic attacks (TIA) related-focus by diffusion weighted magnetic resonance imaging(DWI), and the semi-quantitative characteristics of TIA related-focus on DWI manifestation were researched. Methods: A prospective analysis was performed on 39 TIA patients who were admitted to the Pudong New Area People Hospital and who had also undergone DWI scan 3 , and rADC ratio of the lesion was (-25.8 ± 9.01)%, and rAI ratio was(59.9 ± 12.9)% and compared with that of the contralateral side there was significant difference. Conclusion: The incidence of positivity rate of DWI is more than that obtained by conventional MR imaging. The related focus of TIA are very small and the ADC value of the lesion is decreased slightly, but averge intensity is increased highly. These data may be of value in identifying those TIA patients for whom MRI evaluation with DWI is of great clinical utility. (authors)

  2. Differential diagnosis of benign and malignant breast masses using diffusion-weighted magnetic resonance imaging.

    Science.gov (United States)

    Min, Qinghua; Shao, Kangwei; Zhai, Lulan; Liu, Wei; Zhu, Caisong; Yuan, Lixin; Yang, Jun

    2015-02-07

    Diffusion-weighted magnetic resonance imaging (DW-MRI) is different from conventional diagnostic methods and has the potential to delineate the microscopic anatomy of a target tissue or organ. The purpose of our study was to evaluate the value of DW-MRI in the diagnosis of benign and malignant breast masses, which would help the clinical surgeon to decide the scope and pattern of operation. A total of 52 female patients with palpable solid breast masses received breast MRI scans using routine sequences, dynamic contrast-enhanced imaging, and diffusion-weighted echo-planar imaging at b values of 400, 600, and 800 s/mm(2), respectively. Two regions of interest (ROIs) were plotted, with a smaller ROI for the highest signal and a larger ROI for the overall lesion. Apparent diffusion coefficient (ADC) values were calculated at three different b values for all detectable lesions and from two different ROIs. The sensitivity, specificity, positive predictive value, and positive likelihood ratio of DW-MRI were determined for comparison with histological results. A total of 49 (49/52, 94.2%) lesions were detected using DW-MRI, including 20 benign lesions (two lesions detected in the same patient) and 29 malignant lesions. Benign lesion had a higher mean ADC value than their malignant counterparts, regardless of b value. According to the receiver operating characteristic (ROC) curve, the smaller-range ROI was more effective in differentiation between benign and malignant lesions. The area under the ROC curve was the largest at a b value of 800 s/mm(2). With a threshold ADC value at 1.23 × 10(-3) mm(2)/s, DW-MRI achieved a sensitivity of 82.8%, specificity of 90.0%, positive predictive value of 92.3%, and positive likelihood ratio of 8.3 for differentiating benign and malignant lesions. DW-MRI is an accurate diagnostic tool for differentiation between benign and malignant breast lesions, with an optimal b value of 800 s/mm(2). A smaller-range ROI focusing on the

  3. Respiratory syncytial virus-related encephalitis: magnetic resonance imaging findings with diffusion-weighted study

    International Nuclear Information System (INIS)

    Park, Arim; Suh, Sang-il; Seol, Hae-Young; Son, Gyu-Ri; Lee, Nam-Joon; Lee, Young Hen; Seo, Hyung Suk; Eun, Baik-Lin

    2014-01-01

    Respiratory syncytial virus (RSV) is a common pathogen causing acute respiratory infection in children. Herein, we describe the incidence and clinical and magnetic resonance imaging (MRI) findings of RSV-related encephalitis, a major neurological complication of RSV infection. We retrospectively reviewed the medical records and imaging findings of the patients over the past 7 years who are admitted to our medical center and are tested positive for RSV-RNA by reverse transcriptase PCR. In total, 3,856 patients were diagnosed with RSV bronchiolitis, and 28 of them underwent brain MRI for the evaluation of neurologic symptoms; 8 of these 28 patients had positive imaging findings. Five of these 8 patients were excluded because of non-RSV-related pathologies, such as subdural hemorrhage, brain volume loss due to status epilepticus, periventricular leukomalacia, preexisting ventriculomegaly, and hypoxic brain injury. The incidence of RSV-related encephalitis was as follows: 3/3,856 (0.08 %) of the patients are positive for RSV RNA, 3/28 (10.7 %) of the patient underwent brain MRI for neurological symptom, and 3/8 (37.5 %) of patients revealed abnormal MR findings. The imaging findings were suggestive of patterns of rhombenmesencephalitis, encephalitis with acute disseminated encephalomyelitis, and limbic encephalitis. They demonstrated no diffusion abnormality on diffusion-weighted image and symptom improvement on the follow-up study. Encephalitis with RSV bronchiolitis occurs rarely. However, on brain MRI performed upon suspicion of neurologic involvement, RSV encephalitis is not infrequently observed among the abnormal MR findings and may mimic other viral and limbic encephalitis. Physicians should be aware of this entity to ensure proper diagnosis and neurologic care of RSV-positive patients. (orig.)

  4. Respiratory syncytial virus-related encephalitis: magnetic resonance imaging findings with diffusion-weighted study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Arim; Suh, Sang-il; Seol, Hae-Young [Korea University College of Medicine, Department of Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of); Son, Gyu-Ri; Lee, Nam-Joon [Korea University College of Medicine, Department of Radiology, Korea University Anam Hospital, Seoul (Korea, Republic of); Lee, Young Hen; Seo, Hyung Suk [Korea University College of Medicine, Department of Radiology, Korea University Ansan Hospital, Gyeonggi-do (Korea, Republic of); Eun, Baik-Lin [Korea University College of Medicine, Department of Pediatrics, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2014-02-15

    Respiratory syncytial virus (RSV) is a common pathogen causing acute respiratory infection in children. Herein, we describe the incidence and clinical and magnetic resonance imaging (MRI) findings of RSV-related encephalitis, a major neurological complication of RSV infection. We retrospectively reviewed the medical records and imaging findings of the patients over the past 7 years who are admitted to our medical center and are tested positive for RSV-RNA by reverse transcriptase PCR. In total, 3,856 patients were diagnosed with RSV bronchiolitis, and 28 of them underwent brain MRI for the evaluation of neurologic symptoms; 8 of these 28 patients had positive imaging findings. Five of these 8 patients were excluded because of non-RSV-related pathologies, such as subdural hemorrhage, brain volume loss due to status epilepticus, periventricular leukomalacia, preexisting ventriculomegaly, and hypoxic brain injury. The incidence of RSV-related encephalitis was as follows: 3/3,856 (0.08 %) of the patients are positive for RSV RNA, 3/28 (10.7 %) of the patient underwent brain MRI for neurological symptom, and 3/8 (37.5 %) of patients revealed abnormal MR findings. The imaging findings were suggestive of patterns of rhombenmesencephalitis, encephalitis with acute disseminated encephalomyelitis, and limbic encephalitis. They demonstrated no diffusion abnormality on diffusion-weighted image and symptom improvement on the follow-up study. Encephalitis with RSV bronchiolitis occurs rarely. However, on brain MRI performed upon suspicion of neurologic involvement, RSV encephalitis is not infrequently observed among the abnormal MR findings and may mimic other viral and limbic encephalitis. Physicians should be aware of this entity to ensure proper diagnosis and neurologic care of RSV-positive patients. (orig.)

  5. The role of diffusion-weighted magnetic resonance imaging in the classification of hepatic hydatid cysts

    Energy Technology Data Exchange (ETDEWEB)

    Çeçe, Hasan, E-mail: hasan_cece@yahoo.com [Harran University, Faculty of Medicine, Department of Radiology, 63300 Şanlıurfa (Turkey); Gündoğan, Mehmet, E-mail: drgundogan@hotmail.com [Harran University, Faculty of Medicine, Department of Radiology, 63300 Şanlıurfa (Turkey); Karakaş, Ömer, E-mail: dromerkarakas@hotmail.com [Harran University, Faculty of Medicine, Department of Radiology, 63300 Şanlıurfa (Turkey); Karakaş, Ekrem, E-mail: karakasekrem@yahoo.com [Harran University, Faculty of Medicine, Department of Radiology, 63300 Şanlıurfa (Turkey); Boyacı, Fatıma Nurefşan, E-mail: drnurefsan@yahoo.com [Harran University, Faculty of Medicine, Department of Radiology, 63300 Şanlıurfa (Turkey); Yıldız, Sema, E-mail: drsemayildiz@yahoo.com [Harran University, Faculty of Medicine, Department of Radiology, 63300 Şanlıurfa (Turkey); Özgönül, Abdullah, E-mail: drozgonul@yahoo.com.tr [Harran University, Faculty of Medicine, Department of General Surgery, Şanlıurfa (Turkey); Karakaş, Emel Yiğit, E-mail: e.ygtkarakas@yahoo.com.tr [Şanlıurfa Training and Research Hospital, Department of Internal Medicine, Şanlıurfa (Turkey); and others

    2013-01-15

    The aim of the study was to classify different types of hepatic hydatid cysts (HHCs) by measuring the mean apparent diffusion coefficient (ADC) using diffusion-weighted magnetic resonance imaging (DWI). This prospective study comprised 44 patients. The 44 HHCs were classified using Gharbi ultrasonographic classification (GUC) and then T2WIs and DWIs were obtained. The ADC values were measured of the hydatid cyst (HC) subtypes. The distribution of the ADC values in the cyst groups was compared using the Kruskal–Wallis test for multi groups and the Mann–Whitney U test for paired groups. To evaluate the efficacy of ADC values in cyst diagnosis, receiver operating characteristic (ROC) analysis was performed. According to the GUC, there were 15 type 1, 11 type 2, 7 type 3, 5 type 4 and 6 type 5 HHCs. According to the ADC values in the paired comparisons, while types 1, 2 and 5 HCs were statistically differentiated from all other groups except the type 3 group, the type 4 group was differentiated from all other groups and the type 3 group was only differentiated from the type 4 group. When two groups were formed from the HHC subtypes with types 1, 2, and 3 in one group and types 4 and 5 in the other, a statistically significant difference was determined in the mean ADC values of these new groups. In conclusion the measurement of ADC values can be considered a promising parameter as an alternative to ultrasonography in the determination of subtypes of HHCs.

  6. Comparison of breast cancer detection by diffusion-weighted magnetic resonance imaging and mammography

    International Nuclear Information System (INIS)

    Yoshikawa, Miho I.; Kikuchi, Keiichi; Mochizuki, Teruhito; Ohsumi, Shozo; Sugata, Shigenori; Kataoka, Masaaki; Takashima, Shigemitsu

    2007-01-01

    Breast cancer-detecting ability of diffusion-weighted magnetic resonance imaging (DW-MRI) was investigated by comparing the breast cancer detection rates of DW-MRI and mammography (MMG). The subjects were 48 women who had breast cancer (53 cancer lesions) who underwent DW-MRI before surgery. Altogether, 41 lesions were invasive ductal carcinoma (IDC), 7 were noninvasive ductal carcinoma (NIDC) and 5 were ''others.'' The breast cancer detection rates by MMG and DW-MRI were 84.9% and 94.3% (P -3 , 1.50±0.24 x 10 -3 , 1.12±0.25 x 10 -3 , and 2.01±0.29 x 10 -3 mm 2 /s for IDC, NIDC, others, and normal breast, respectively, showing that the values of IDC and NIDC were significantly different from that of the normal breast (P<0.001 each). A significant difference was also noted between IDC and NIDC (P<0.001). DW-MRI may be useful for detecting breast cancer in a wide age group of women, including young women with dense mammary glands. (author)

  7. Diffusion-weighted magnetic resonance imaging (MRI) in acute brain stem infarction

    International Nuclear Information System (INIS)

    Narisawa, Aya; Shamoto, Hiroshi; Shimizu, Hiroaki; Tominaga, Teiji; Yoshimoto, Takashi

    2001-01-01

    Diffusion-weighted magnetic resonance imaging (DWI) provides one of the earliest demonstrations of ischemic lesions. However some lesions may be missed in the acute stage due to technical limitation of DWI. We therefore conducted the study to clarify the sensitivity of DWI to acute brain stem infarctions. Twenty-eight patients with the final diagnosis of brain stem infarction (midbrain 2, pons 9, medulla oblongata 17) who had been examined by DWI within 24 hours of onset were retrospectively analyzed for how sensitively the initial DWI demonstrated the final ischemic lesion. Only obvious (distinguishable with DWI alone without referring clinical symptoms and other informations) hyperintensity on DWI was regarded to show an ischemic lesion. Sixteen (57.1%) out of 28 patients had brain stem infarctions demonstrated by initial DWI. In the remaining 12 cases, no obvious ischemic lesion was evident on initial DWI. Subsequent MRI studies obtained 127 hours, on average after the onset showed infarction in the medulla oblongate in 11 cases and in the pons in one case. Negative findings of DWI in the acute stage does not exclude possibility of the brain stem infarction, in particularly medulla oblongata infarction. (author)

  8. Diffusion-Weighted Magnetic Resonance Imaging of Cerebrospinal Fluid in Patients with and without Communicating Hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Nasel, C.; Gentzsch, S.; Heimberger, K. [Cerebrovascular Imaging Workgroup of the Div. of Neuroradiology, Dept. of Radiology, Medical Univ. Vienna, Vienna (Austria)

    2007-09-15

    Background: Recent concepts about cerebrospinal fluid (CSF) circulation in communicating hydrocephalus (CoHy), which is also termed 'restricted arterial pulsation hydrocephalus,' suggest reduced arterial pulsations of subarachnoid vessels with a smaller amount of CSF shifted in subarachnoid spaces during the early systole. The postulated restriction of subarachnoid arterial pulsations in CoHy should induce a smaller motion artifact and reduced local stream effects in CSF in magnetic resonance (MR) diffusion-weighted imaging (DWI). Purpose: To investigate the maximum diffusivity in CSF in patients with and without CoHy using DWI. Material and Methods: 12 patients without CSF circulation disturbances and six cases with proven CoHy were assessed. Diffusion was measured in six non collinear directions without triggering the arterial pulse wave (scan time 6:45 min, voxel size 2x2x2 mm). Due to expected artifacts, the calculated maximum diffusivity was called apparent diffusivity. Regional high and low apparent diffusivity was assessed in CSF spaces on newly created 3D CSF motion maps. Results: Patients with regular CSF circulation exhibited high apparent diffusivity in CSF in basal subarachnoid spaces, whereas apparent diffusivity was low there in patients with CoHy. Conclusion: DWI opens a feasible approach to study CSF motion in the neurocranium. Restricted arterial pulsations seem to be involved in CoHy.

  9. Diffusion-Weighted Magnetic Resonance Imaging of Cerebrospinal Fluid in Patients with and without Communicating Hydrocephalus

    International Nuclear Information System (INIS)

    Nasel, C.; Gentzsch, S.; Heimberger, K.

    2007-01-01

    Background: Recent concepts about cerebrospinal fluid (CSF) circulation in communicating hydrocephalus (CoHy), which is also termed 'restricted arterial pulsation hydrocephalus,' suggest reduced arterial pulsations of subarachnoid vessels with a smaller amount of CSF shifted in subarachnoid spaces during the early systole. The postulated restriction of subarachnoid arterial pulsations in CoHy should induce a smaller motion artifact and reduced local stream effects in CSF in magnetic resonance (MR) diffusion-weighted imaging (DWI). Purpose: To investigate the maximum diffusivity in CSF in patients with and without CoHy using DWI. Material and Methods: 12 patients without CSF circulation disturbances and six cases with proven CoHy were assessed. Diffusion was measured in six non collinear directions without triggering the arterial pulse wave (scan time 6:45 min, voxel size 2x2x2 mm). Due to expected artifacts, the calculated maximum diffusivity was called apparent diffusivity. Regional high and low apparent diffusivity was assessed in CSF spaces on newly created 3D CSF motion maps. Results: Patients with regular CSF circulation exhibited high apparent diffusivity in CSF in basal subarachnoid spaces, whereas apparent diffusivity was low there in patients with CoHy. Conclusion: DWI opens a feasible approach to study CSF motion in the neurocranium. Restricted arterial pulsations seem to be involved in CoHy

  10. Thin-Section Diffusion-Weighted Magnetic Resonance Imaging of the Brain with Parallel Imaging

    International Nuclear Information System (INIS)

    Oner, A.Y.; Celik, H.; Tali, T.; Akpek, S.; Tokgoz, N.

    2007-01-01

    Background: Thin-section diffusion-weighted imaging (DWI) is known to improve lesion detectability, with long imaging time as a drawback. Parallel imaging (PI) is a technique that takes advantage of spatial sensitivity information inherent in an array of multiple-receiver surface coils to partially replace time-consuming spatial encoding and reduce imaging time. Purpose: To prospectively evaluate a 3-mm-thin-section DWI technique combined with PI by means of qualitative and quantitative measurements. Material and Methods: 30 patients underwent conventional echo-planar (EPI) DWI (5-mm section thickness, 1-mm intersection gap) without parallel imaging, and thin-section EPI-DWI with PI (3-mm section thickness, 0-mm intersection gap) for a b value of 1000 s/mm 2 , with an imaging time of 40 and 80 s, respectively. Signal-to-noise ratio (SNR), relative signal intensity (rSI), and apparent diffusion coefficient (ADC) values were measured over a lesion-free cerebral region on both series by two radiologists. A quality score was assigned for each set of images to assess the image quality. When a brain lesion was present, contrast-to-noise ratio (CNR) and corresponding ADC were also measured. Student t-tests were used for statistical analysis. Results: Mean SNR values of the normal brain were 33.61±4.35 and 32.98±7.19 for conventional and thin-slice DWI (P>0.05), respectively. Relative signal intensities were significantly higher on thin-section DWI (P 0.05). Quality scores and overall lesion CNR were found to be higher in thin-section DWI with parallel imaging. Conclusion: A thin-section technique combined with PI improves rSI, CNR, and image quality without compromising SNR and ADC measurements in an acceptable imaging time. Keywords: Brain; DWI; parallel imaging; thin section

  11. Transient Splenial Lesion of Corpus Callosum Associated with Antiepileptic Drug: Conventional and Diffusion-weighted Magnetic Resonance Images

    Energy Technology Data Exchange (ETDEWEB)

    Hakyemez, B.; Erdogan, C.; Yildirim, N.; Gokalp, G.; Parlak, M. [Uludag Univ. Medical School, Bursa (Turkey). Dept. of Radiology

    2005-11-01

    Transient focal lesions of splenium of corpus callosum can be seen as a component of many central nervous system diseases, including antiepileptic drug toxicity. The conventional magnetic resonance (MR) findings of the disease are characteristic and include ovoid lesions with high signal intensity at T2-weighted MRI. Limited information exists about the diffusion-weighted MRI characteristics of these lesions vanishing completely after a period of time. We examined the conventional, FLAIR, and diffusion-weighted MR images of a patient complaining of depressive mood and anxiety disorder after 1 year receiving antiepileptic medication.

  12. The diagnostic value of diffusion-weighted magnetic resonance imaging in soft tissue abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Unal, Ozkan; Koparan, Halil Ibrahim [Yuezuencue Yil University, Department of Radiology, Van (Turkey); Avcu, Serhat, E-mail: serhatavcu@hotmail.com [Yuezuencue Yil University, Department of Radiology, Van (Turkey); Kalender, Ali Murat [Yuezuencue Yil University, Department of Orthopaedics, General Surgery, Van (Turkey); Kisli, Erol [Yuezuencue Yil University, Department of General Surgery, Van (Turkey)

    2011-03-15

    Purpose: To study the diagnostic value of diffusion-weighted imaging (DWI) in soft tissue abscesses. Materials and methods: Fifty patients were included in this study who were thought to have soft tissue abscess or cystic lesion as a result of clinical and radiological examinations. Localisations of the lesions were: 1 periorbital, 3 breast, 14 intraabdominal, and 32 intramuscular lesions. After other radiological examinations, DWI was performed. The signal intensity values of the lesions were evaluated qualitatively according to the hyperintensity on b-1000 DWI, using 1.5 T MR system. All of the lesions were aspirated after DWI, and detection of pus in the aspiration material was accepted as gold standard for the diagnosis of abscess. Results: In 38 of the 50 patients, hyperintensity was obtained on diffusion-weighted images. False-positive results were maintained in 2 of these patients, and true-positive results were maintained in 36 of them. In 11 of the 50 patients, hypointensity was visualised on diffusion-weighted images. False-negative results were maintained in 3 of these patients, and true-negative results were maintained in 8 of them. An abscess which was seen on post-contrast conventional MRI could not be seen on DWI, and this was regarded as false-negative. Conclusion: The sensitivity and specificity of diffusion-weighted images for detecting soft tissue abscesses were found to be 92% and 80%, respectively. DWI has a high diagnostic value in soft tissue abscesses, and is an important imaging modality that may be used for the differentiation of cysts and abscesses.

  13. The diagnostic value of diffusion-weighted magnetic resonance imaging in soft tissue abscesses

    International Nuclear Information System (INIS)

    Unal, Ozkan; Koparan, Halil Ibrahim; Avcu, Serhat; Kalender, Ali Murat; Kisli, Erol

    2011-01-01

    Purpose: To study the diagnostic value of diffusion-weighted imaging (DWI) in soft tissue abscesses. Materials and methods: Fifty patients were included in this study who were thought to have soft tissue abscess or cystic lesion as a result of clinical and radiological examinations. Localisations of the lesions were: 1 periorbital, 3 breast, 14 intraabdominal, and 32 intramuscular lesions. After other radiological examinations, DWI was performed. The signal intensity values of the lesions were evaluated qualitatively according to the hyperintensity on b-1000 DWI, using 1.5 T MR system. All of the lesions were aspirated after DWI, and detection of pus in the aspiration material was accepted as gold standard for the diagnosis of abscess. Results: In 38 of the 50 patients, hyperintensity was obtained on diffusion-weighted images. False-positive results were maintained in 2 of these patients, and true-positive results were maintained in 36 of them. In 11 of the 50 patients, hypointensity was visualised on diffusion-weighted images. False-negative results were maintained in 3 of these patients, and true-negative results were maintained in 8 of them. An abscess which was seen on post-contrast conventional MRI could not be seen on DWI, and this was regarded as false-negative. Conclusion: The sensitivity and specificity of diffusion-weighted images for detecting soft tissue abscesses were found to be 92% and 80%, respectively. DWI has a high diagnostic value in soft tissue abscesses, and is an important imaging modality that may be used for the differentiation of cysts and abscesses.

  14. Giant Vertebral Notochordal Rest: Magnetic Resonance and Diffusion Weighted Imaging Findings

    International Nuclear Information System (INIS)

    Oner, Ali Yusuf; Akpek, Sergin; Tali, Turgut; Ucar, Murat

    2009-01-01

    A giant vertebral notochordal rest is a newly described, benign entity that is easily confused with a vertebral chordoma. As microscopic notochordal rests are rarely found in adult autopsies, the finding of a macroscopic vertebral lesion is a new entity with only seven previously presented cases. We report here radiological findings, including diffusion weighted images, of a patient with a giant notochordal remnant confined to the L5 vertebra, with an emphasis on its distinction from a chordoma

  15. Sequential Magnetic Resonance Imaging Finding of Intramedullary Spinal Cord Abscess including Diffusion Weighted Image: a Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Jae Eun; Lee, Seung Young; Cha, Sang Hoon; Cho, Bum Sang; Jeon, Min Hee; Kang, Min Ho [Chungbuk National University College of Medicine, Cheongju (Korea, Republic of)

    2011-04-15

    Intramedullary spinal cord abscess (ISCA) is a rare infection of the central nervous system. We describe the magnetic resonance imaging (MRI) findings, including the diffusion-weighted imaging (DWI) findings, of ISCA in a 78-year-old man. The initial conventional MRI of the thoracic spine demonstrated a subtle enhancing nodule accompanied by significant edema. On the follow-up MRI after seven days, the nodule appeared as a ring-enhancing nodule. The non-enhancing central portion of the nodule appeared hyperintense on DWI with a decreased apparent diffusion coefficient (ADC) value on the ADC map. We performed myelotomy and surgical drainage, and thick, yellowish pus was drained

  16. Sandwich sign of Borrmann type 4 gastric cancer on diffusion-weighted magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiao-Peng, E-mail: zxp@bjcancer.org [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Radiology, Peking University School of Oncology, Beijing Cancer Hospital and Institute, No. 52 Fu Cheng Road, Hai Dian District, Beijing 100142 (China); Tang, Lei; Sun, Ying-Shi [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Radiology, Peking University School of Oncology, Beijing Cancer Hospital and Institute, No. 52 Fu Cheng Road, Hai Dian District, Beijing 100142 (China); Li, Zi-Yu; Ji, Jia-Fu [Department of Gastrointestinal Surgery, Peking University School of Oncology, Beijing Cancer Hospital and Institute, No. 52 Fu Cheng Road, Hai Dian District, Beijing 100142 (China); Li, Xiao-Ting [Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Radiology, Peking University School of Oncology, Beijing Cancer Hospital and Institute, No. 52 Fu Cheng Road, Hai Dian District, Beijing 100142 (China); Liu, Yi-Qiang [Department of Pathology, Peking University School of Oncology, Beijing Cancer Hospital and Institute, No. 52 Fu Cheng Road, Hai Dian District, Beijing 100142 (China); Wu, Qi [Department of Endoscopy, Peking University School of Oncology, Beijing Cancer Hospital and Institute, No. 52 Fu Cheng Road, Hai Dian District, Beijing 100142 (China)

    2012-10-15

    Objective: To assess the appearance of Borrmann type 4 (BT-4) gastric cancer on diffusion-weighted magnetic resonance imaging (DWI) and to investigate the potential of qualitative and quantitative DW images analysis to differentiate BT-4 gastric cancer from poorly distended normal stomach wall. Materials and methods: DWI was performed on 23 patients with BT-4 gastric cancer and 23 healthy volunteers. The signal characteristics and correlated histopathological basis of the cancers on DWI were investigated. The contrast-to-noise ratios (CNR) of cancer were compared between DWI and T1WI/T2WI{sub .} The thickness and apparent diffusion coefficient (ADC) of cancer and normal stomach wall were compared. Results: All of the gastric cancers displayed hyperintensity compared to the nearby normal gastric wall on DWI. A three-layer sandwich sign that demonstrated high signal intensity in the inner and outer layer, and low signal intensity in the intermediate layer was observed in 69.6% of cancers on DWI. The low signal intensity represents the muscularis propria through the comparison with pathology, and it is postulated that scattering distribution of the cancer cells in this layer causes less damage and subsequently less restriction of water movement, which causes the low signal intensity on DWI. The CNR obtained with DWI was higher than that with T1WI and T2WI (P < 0.001). The mean ADC value of BT-4 gastric cancer was significantly lower than the poorly distended normal stomach wall (1.12 ± 0.23 × 10{sup −3} mm{sup 2}/s vs. 1.93 ± 0.22 × 10{sup −3} mm{sup 2}/s, P < 0.01). Conclusion: DWI can highlight the signals of BT-4 gastric cancer which may present a characteristic three-layer sandwich sign, and ADC values are helpful in the discrimination of gastric cancer from poorly distended stomach wall.

  17. Role of magnetic resonance diffusion-weighted imaging in evaluating response after chemoembolization of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Yuan Zheng; Ye Xiaodan; Dong Sheng; Xu Lichao; Xu Xueyuan; Liu Shiyuan; Xiao Xiangsheng

    2010-01-01

    Objective: To investigate the value of hepatocellular carcinoma pretreatment apparent diffusion coefficients (ADCs) and its ADCs changes after treatment in predicting and early monitoring the response after chemoembolization. Materials and methods: Twenty-five responding and nine nonresponding hepatocellular carcinoma lesions were prospectively evaluated with magnetic resonance diffusion-weighted imaging in 24 h before and in 48 h after chemoembolization. Quantitative ADC maps were calculated with images with b values of 0 and 500 s/mm 2 . Results: Nonresponding lesions had a significantly higher pretreatment mean ADC than did responding lesions (1.726 ± 0.323 x 10 -3 mm 2 /s vs.1.294 ± 0.185 10 -3 mm 2 /s, P ≤ 0.001). The results of receiver operator characteristic (ROC) analysis for identification of nonresponding lesions showed that threshold ADC value of 1.618 x 10 -3 mm 2 /s had 96.0% sensitivity and 77.8% specificity. After transarterial chemoembolization, responding lesions had a significant increase in %ADC values than did nonresponding lesions (32.63% vs. 5.24%, P = 0.025). The results of ROC analysis for identification of responding lesions showed that threshold %ADC value of 16.21% had 72% sensitivity and 100% specificity. No significant change was observed in normal liver parenchyma (P = 0.862) and spleen (P = 0.052). Conclusion: High pretreatment mean ADC value of hepatocellular carcinoma was predictive of poor response to chemoembolization. A significant increase in %ADC value was observed in lesions that responded to chemoembolization.

  18. Sandwich sign of Borrmann type 4 gastric cancer on diffusion-weighted magnetic resonance imaging

    International Nuclear Information System (INIS)

    Zhang, Xiao-Peng; Tang, Lei; Sun, Ying-Shi; Li, Zi-Yu; Ji, Jia-Fu; Li, Xiao-Ting; Liu, Yi-Qiang; Wu, Qi

    2012-01-01

    Objective: To assess the appearance of Borrmann type 4 (BT-4) gastric cancer on diffusion-weighted magnetic resonance imaging (DWI) and to investigate the potential of qualitative and quantitative DW images analysis to differentiate BT-4 gastric cancer from poorly distended normal stomach wall. Materials and methods: DWI was performed on 23 patients with BT-4 gastric cancer and 23 healthy volunteers. The signal characteristics and correlated histopathological basis of the cancers on DWI were investigated. The contrast-to-noise ratios (CNR) of cancer were compared between DWI and T1WI/T2WI . The thickness and apparent diffusion coefficient (ADC) of cancer and normal stomach wall were compared. Results: All of the gastric cancers displayed hyperintensity compared to the nearby normal gastric wall on DWI. A three-layer sandwich sign that demonstrated high signal intensity in the inner and outer layer, and low signal intensity in the intermediate layer was observed in 69.6% of cancers on DWI. The low signal intensity represents the muscularis propria through the comparison with pathology, and it is postulated that scattering distribution of the cancer cells in this layer causes less damage and subsequently less restriction of water movement, which causes the low signal intensity on DWI. The CNR obtained with DWI was higher than that with T1WI and T2WI (P −3 mm 2 /s vs. 1.93 ± 0.22 × 10 −3 mm 2 /s, P < 0.01). Conclusion: DWI can highlight the signals of BT-4 gastric cancer which may present a characteristic three-layer sandwich sign, and ADC values are helpful in the discrimination of gastric cancer from poorly distended stomach wall

  19. Diffusion-weighted perinatal postmortem magnetic resonance imaging as a marker of postmortem interval

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); UCL Institute of Child Health, Imaging and Biophysics, London (United Kingdom); Price, Gemma C. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); Carmichael, David W. [UCL Institute of Child Health, Imaging and Biophysics, London (United Kingdom); Jones, Rod; Norman, Wendy; Taylor, Andrew M. [Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiorespiratory Division, London (United Kingdom); UCL Institute of Cardiovascular Science, Centre for Cardiovascular Imaging, London (United Kingdom); Sebire, Neil J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Histopathology, London (United Kingdom); UCL Institute of Child Health, Histopathology, London (United Kingdom)

    2015-05-01

    To evaluate perinatal body organ apparent diffusion coefficient (ADC) values at postmortem magnetic resonance imaging (PMMR) in order to evaluate postmortem changes. Postmortem diffusion-weighted imaging (DWI) of the thorax and abdomen were performed with diffusion gradient values b = 0, 500, and 1000 s/mm{sup 2} on 15 foetal and childhood cases (mean 33.3 ± 7.8 weeks gestation) compared to 44 live infants (mean age 75.5 ± 53.4 days). Mean ADC values were calculated from regions of interest (ROIs) for the lungs, liver, spleen and renal cortex, compared to normative live infantile body ADC values of similar gestational age. Mean ADC values were significantly lower in postmortem cases than in normal controls for liver (0.88 10{sup -3} mm{sup 2}/s ± SD 0.39 vs. 1.13 ± 0.13; p < 0.05) and renal cortex (0.85 ± 0.26 vs. 1.19 ± 0.13; p < 0.05) but not spleen or muscle. Mean lung ADC values were significantly higher than normal controls (1.06 ± 0.18 vs. 0 ± 0; p < 0.001), and there was a significant correlation between postmortem interval and lung ADC (R{sup 2} = 0.55). Lung PMMR ADC values are related to postmortem interval, making them a potential marker of time since death. Further research is needed to understand the organ-specific changes which occur in the postmortem period. (orig.)

  20. Role of magnetic resonance diffusion-weighted imaging in evaluating response after chemoembolization of hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Zheng, E-mail: yuanzheng0404@163.co [Department of Radiology, Affiliated Changzheng Hospital, Second Military Medical University, 415 Feng Yang Road, Shanghai 200003 (China); Ye Xiaodan [Department of Radiology, Affiliated Changzheng Hospital, Second Military Medical University, 415 Feng Yang Road, Shanghai 200003 (China); Department of Radiology, Affiliated Shanghai Chest Hospital, Shanghai Jiaotong University, 241 West Huai Hai Road, Shanghai 200030 (China); Dong Sheng, E-mail: dongsheng2828@hotmail.co [Department of Radiology, Affiliated Changzheng Hospital, Second Military Medical University, 415 Feng Yang Road, Shanghai 200003 (China); Xu Lichao; Xu Xueyuan; Liu Shiyuan; Xiao Xiangsheng [Department of Radiology, Affiliated Changzheng Hospital, Second Military Medical University, 415 Feng Yang Road, Shanghai 200003 (China)

    2010-07-15

    Objective: To investigate the value of hepatocellular carcinoma pretreatment apparent diffusion coefficients (ADCs) and its ADCs changes after treatment in predicting and early monitoring the response after chemoembolization. Materials and methods: Twenty-five responding and nine nonresponding hepatocellular carcinoma lesions were prospectively evaluated with magnetic resonance diffusion-weighted imaging in 24 h before and in 48 h after chemoembolization. Quantitative ADC maps were calculated with images with b values of 0 and 500 s/mm{sup 2}. Results: Nonresponding lesions had a significantly higher pretreatment mean ADC than did responding lesions (1.726 {+-} 0.323 x 10{sup -3} mm{sup 2}/s vs.1.294 {+-} 0.185 10{sup -3} mm{sup 2}/s, P {<=} 0.001). The results of receiver operator characteristic (ROC) analysis for identification of nonresponding lesions showed that threshold ADC value of 1.618 x 10{sup -3} mm{sup 2}/s had 96.0% sensitivity and 77.8% specificity. After transarterial chemoembolization, responding lesions had a significant increase in %ADC values than did nonresponding lesions (32.63% vs. 5.24%, P = 0.025). The results of ROC analysis for identification of responding lesions showed that threshold %ADC value of 16.21% had 72% sensitivity and 100% specificity. No significant change was observed in normal liver parenchyma (P = 0.862) and spleen (P = 0.052). Conclusion: High pretreatment mean ADC value of hepatocellular carcinoma was predictive of poor response to chemoembolization. A significant increase in %ADC value was observed in lesions that responded to chemoembolization.

  1. Value of 3 Tesla diffusion-weighted magnetic resonance imaging for assessing liver fibrosis.

    Science.gov (United States)

    Papalavrentios, Lavrentios; Sinakos, Emmanouil; Chourmouzi, Danai; Hytiroglou, Prodromos; Drevelegas, Konstantinos; Constantinides, Manos; Drevelegas, Antonios; Talwalkar, Jayant; Akriviadis, Evangelos

    2015-01-01

    Limited data are available regarding the role of magnetic resonance imaging (MRI), particularly the new generation 3 Tesla technology, and especially diffusion-weighted imaging (DWI) in predicting liver fibrosis. The aim of our pilot study was to assess the clinical performance of the apparent diffusion coefficient (ADC) of liver parenchyma for the assessment of liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). 18 patients with biopsy-proven NAFLD underwent DWI with 3 Tesla MRI. DWI was performed with single-shot echo-planar technique at b values of 0-500 and 0-1000 s/mm 2 . ADC was measured in four locations in the liver and the mean ADC value was used for analysis. Staging of fibrosis was performed according to the METAVIR system. The median age of patients was 52 years (range 23-73). The distribution of patients in different fibrosis stages was: 0 (n=1), 1 (n=7), 2 (n=1), 3 (n=5), 4 (n=4). Fibrosis stage was poorly associated with ADC at b value of 0-500 s/mm 2 (r= -0.30, P=0.27). However it was significantly associated with ADC at b value of 0-1000 s/mm 2 (r= -0.57, P=0.01). For this b value (0-1000 s/mm 2 ) the area under receiver-operating characteristic curve was 0.93 for fibrosis stage ≥3 and the optimal ADC cut-off value was 1.16 ×10 -3 mm 2 /s. 3 Tesla DWI can possibly predict the presence of advanced fibrosis in patients with NAFLD.

  2. Diffusion-weighted magnetic resonance imaging - a new instrument in the diagnosis of Creutzfeldt-Jacob's disease

    International Nuclear Information System (INIS)

    Romi, Fredrik; Smivoll, Alf Inge; Moerk, Sverre; Tysnes, Ole-Bjoern

    2000-01-01

    Creutzfeldt-Jacob's disease (CID) is characterised by rapidly progressive dementia, ataxia, myoclonus and several other neurological deficits. It generally affects older adults and occurs in sporadic, genetic and iatrogenic forms. Death occurs usually within one year after onset of the disease. The diagnosis is based on clinical criteria, neuro physiological and radiological findings and confirmed by post mortal histopathology. During the last two years several cases of CID have been reported with diffusion-weighted magnetic resonance imaging (MR) abnormalities represented by increased signal intensity indicating reduced diffusion in basal ganglia and/or cortex cerebric. These abnormalities seem to be characteristic of CID. We report a case of CID in a 54 year old woman who developed vertigo, nystagmus, ataxia, myoclonus and dementia over a period of eight months. Diffusion-weighted magnetic resonance imaging showed increased signal intensity in corpus striatum and gyrus conguli. The diagnosis was post mortally confirmed with histopathology. (Author) 7 figs., 15 refs

  3. USE OF DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING FOR REVEALING HYPOXIC-ISCHEMIC BRAIN LESIONS IN NEONATES

    Directory of Open Access Journals (Sweden)

    E. V. Shimchenko

    2014-01-01

    Full Text Available The article presents advantages of use of diffusion-weighted magnetic resonance imaging (DW MRI for revealing hypoxic-ischemic brain lesions in neonates. The trial included 97 neonates with perinatal brain lesion who had been undergoing treatment at a resuscitation department or neonatal pathology department in the first month of life. The article shows high information value of diffusion-weighted images (DWI for diagnostics of hypoxic-ischemic lesions in comparison with regular standard modes. In the event of no structural brain lesions of neonates, pronounced increase in signal characteristics revealed by DWI indicated considerable pathophysiological alterations. Subsequently, children developed structural alterations in the form of cystic encephalomalacia with expansion of cerebrospinal fluid spaces manifested with pronounced neurological deficit. DW MRI has been offered as a method of prognosticating further neurological development of children on early stages. 

  4. Initial experience of functional imaging of upper urinary tract neoplasm by diffusion-weighted magnetic resonance imaging

    International Nuclear Information System (INIS)

    Yoshida, Soichiro; Masuda, Hitoshi; Saito, Kazutaka; Kawakami, Satoru; Kihara, Kazunori; Ishii, Chikako

    2008-01-01

    Diffusion-weighted (DW) magnetic resonance imaging (MRI) provides functional information widely used in the diagnosis of acute cerebral stroke. We reported our initial experience of this imaging technique of upper urinary tract (UUT) urothelial carcinoma (UC). Diffusion-weighted magnetic resonance imaging was carried out in 10 consecutive patients with suspected UUT UC. With conventional imaging, seven were diagnosed as having renal pelvic tumors and two were highly suspected of having UUT UC. These nine patients were diagnosed histopathologically as having renal pelvic UC by subsequent operation. The last patient was confirmed as experiencing benign stenosis. DW MRI was obtained with a 1.5-T MR imager without a breath-holding sequence. The apparent diffusion coefficient (ADC) values of renal parenchyma, dilated collecting system, and tumor were calculated. The differences were analyzed using Wilcoxon t-test. On DW MRI, all nine tumors showed hyperintensity with negligible urinary intensity. Two cases of highly suspected UUT UC with unclear conventional MRI had high signal intensity and contrast. The case of benign stenosis had negative DW MRI. The median (range) ADC value of the tumor (0.803 [0.412-0.958] x 10 -3 mm 2 /s) was significantly lower than those of the dilated collecting system (2.19 [1.42-2.40] x 10 -3 ) and renal parenchyma (1.28 [0.922-1.45] x 10 -3 , respectively (P<0.01 and P<0.01). This is the first report on the application of DW MRI for a series of UUT UC. With this technique, a clear demonstration of UUT UC could be obtained. Moreover, this imaging technique is potentially useful to identify small lesions if they have a low diffusion coefficient. (author)

  5. Focal Pancreatitis Mimicking Pancreatic Mass: Magnetic Resonance Imaging (MRI)/Magnetic Resonance Cholangiopancreatography (MRCP) Findings Including Diffusion-Weighted MRI

    International Nuclear Information System (INIS)

    Momtahen, A.J.; Balci, N.C.; Alkaade, S.; Akduman, E.I.; Burton, F.R.

    2008-01-01

    Background: Focal pancreatitis (FP) is a confined inflammation that mimics a pancreatic mass. Its imaging diagnosis is important to avoid unnecessary procedures. Purpose: To describe the spectrum of magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP) and diffusion-weighted MRI (DWI) findings of focal pancreatitis mimicking pancreatic masses. Material and Methods: Findings of MRI/MRCP including DWI with a b value of 0 and 600 s/mm2 in 14 patients with pancreatic masses on MRI were retrospectively reviewed and compared to normal pancreas in 14 patients as a control group. Results: FP revealed hypointense signal intensity (SI) (3/14), hypo- to isointense SI (7/14), or isointense SI (4/14) on T1-weighted images, and hypointense SI (1/14), isointense SI (5/14), iso- to hyperintense SI (7/14), or hyperintense SI (1/14) on T2-weighted images compared to remaining pancreas (RP). MRCP images revealed dilatation of the common bile duct (CBD) and main pancreatic duct (MPD) (5/14), dilatation of the MPD only (3/14), dilatation of the CBD only (3/14), and normal MPD and CBD (3/14). Both FP and RP revealed three types of time-signal intensity curves: 1) rapid rise to a peak, with a rapid decline (FP=2, RP=4), 2) slow rise to a peak, followed by a slow decline (FP=5, RP=4), and 3) slower rise to a peak, with a slow decline or plateau (FP=7, RP=6). Mean apparent diffusion coefficient (ADC) values for FP and RP were 2.09±0.18 and 2.03±0.2x10 -3 mm 2 /s, respectively. ADC values of FP and RP revealed no significant difference. Conclusion: The spectrum of imaging findings of focal pancreatitis on MRI/MRCP including DWI was described. Findings of FP were not distinctive as compared to the remaining pancreas

  6. Role of apparent diffusion coefficient values and diffusion weighted magnetic resonance imaging in differentiation between benign and malignant thyroid nodules

    International Nuclear Information System (INIS)

    Incedayi, M.; Sivrioglu, A.; Mutlu, H.; Sonmez, G.; Velioglu, M.; Sildiroglu, O.; Basekim, C.; Kizilkaya, E.

    2012-01-01

    Full text: Objective: The purpose of the study was to differentiate between benign and malignant thyroid nodules using nodule-spinal cord signal intensity and nodule apparent diffusion coefficient (ADC) ratios on diffusion weighted magnetic resonance imaging. Materials and methods: Forty-four patients (27 females, 17 males; mean age 49) with nodules who underwent diffusion weighted magnetic resonance imaging (DW-MRI) were included in this study. The images were acquired with 0, 50, 400 and 1000 s/mm 2 b values. ADC maps were calculated afterwards. Fine needle aspiration biopsies (FNAB) were performed at the same day with DW-MRI acquisition. The diagnosis in patients where malignity was detected after FNAB was confirmed by histopathologic analysis of the operation material. The signal intensities of the spinal cord and the nodule were measured additionally, over b-1000 diffusion weighted images. Nodule /cord signal intensity (SI) ratios were obtained and the digital values were calculated by dividing to ADC values estimated for each nodule. Statistical analysis was performed. Results: The (nodule SI-cord SI)/nodule ADC ratio is calculated in the DW images and a statistically significant relationship was found between this ratio and the histopathology of the nodules (p<0.001). The ratio was determined as 0.27 in benign, and 0.86 in malignant lesions. The result of ROC analysis was statistically significant, and the area under Receiver Operating Characteristic (ROC) curve (100%) was considerably high. The threshold value was calculated as 0.56 according to the ROC analysis. According to this threshold value, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy rates for (nodule SI/cord SI)/ADC ratios in differentiating benign from malignant thyroid nodules are calculated as 100%, 97%, 83%, 100%, and 98%, respectively. Conclusion: We have found that (nodule/cord SI)/ nodule ADC ratio has the highest values for

  7. Neural - levelset shape detection segmentation of brain tumors in dynamic susceptibility contrast enhanced and diffusion weighted magnetic resonance images

    International Nuclear Information System (INIS)

    Vijayakumar, C.; Bhargava, Sunil; Gharpure, Damayanti Chandrashekhar

    2008-01-01

    A novel Neuro - level set shape detection algorithm is proposed and evaluated for segmentation and grading of brain tumours. The algorithm evaluates vascular and cellular information provided by dynamic contrast susceptibility magnetic resonance images and apparent diffusion coefficient maps. The proposed neural shape detection algorithm is based on the levels at algorithm (shape detection algorithm) and utilizes a neural block to provide the speed image for the level set methods. In this study, two different architectures of level set method have been implemented and their results are compared. The results show that the proposed Neuro-shape detection performs better in differentiating the tumor, edema, necrosis in reconstructed images of perfusion and diffusion weighted magnetic resonance images. (author)

  8. Diagnostic Accuracy of Diffusion Weighted Magnetic Resonance Imaging in the Detection of Myometrial Invasion in Endometrial Carcinoma

    International Nuclear Information System (INIS)

    Masroor, I.; Hussain, Z.; Taufiq, M.

    2016-01-01

    Objective: To determine the diagnostic accuracy of Diffusion-Weighted Magnetic Resonance Imaging (DWMRI) in the detection of myometrial invasion in endometrial cancer taking histopathology as gold standard. Study Design: Cross-sectional validation study. Place and Duration of Study: Department of Radiology, The Aga Khan University Hospital, Karachi, from January to December 2012. Methodology: DWMRI (b-value = 50,400 and 800 s/mm2) was performed in 85 patients of biopsy-proven endometrial carcinoma before hysterectomy using body and spine coil at 1.5 Tesla. DWI was evaluated for presence of myometrial invasion by tumor with histopathology as gold standard. Sensitivity, specificity, the negative predictive value and positive predictive value and accuracy of DWI were assessed against the gold standard. Results: On DWI, superficial myometrial invasion was found in 42 patients and deep myometrial invasion in 43. On histopathology, superficial myometrial invasion was found in 53 patients and deep myometrial invasion in 32. Hence sensitivity, specificity, positive predictive value, negative predictive value and accuracy for the assessment of myometrial invasion by endometrial tumor on DW images was 90 percentage, 73 percentage, 67 percentage, 92 percentage and 80 percentage, respectively. Diagnostic accuracy of diffusion-weighted magnetic resonance imaging in detection of myometrial invasion in endometrial cancer was 80 percentage. Conclusion: DWI is highly accurate in assessing myometrial invasion and can be used as an adjunct to routine MRI for pre-operative evaluation of myometrial invasion of endometrial cancer. (author)

  9. Improved longitudinal length accuracy of gross tumor volume delineation with diffusion weighted magnetic resonance imaging for esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Hou, Dong-Liang; Shi, Gao-Feng; Gao, Xian-Shu; Asaumi, Junichi; Li, Xue-Ying; Liu, Hui; Yao, Chen; Chang, Joe Y

    2013-01-01

    To analyze the longitudinal length accuracy of gross tumor volume (GTV) delineation with diffusion weighted magnetic resonance imaging for esophageal squamous cell carcinoma (SCC). Forty-two patients from December 2011 to June 2012 with esophageal SCC who underwent radical surgery were analyzed. Routine computed tomography (CT) scan, T2-weighted MRI and diffusion weighted magnetic resonance imaging (DWI) were employed before surgery. Diffusion-sensitive gradient b-values were taken at 400, 600, and 800 s/mm 2 . Gross tumor volumes (GTV) were delineated using CT, T2-weighted MRI and DWI on different b-value images. GTV longitude length measured using the imaging modalities listed above was compared with pathologic lesion length to determine the most accurate imaging modality. CMS Xio radiotherapy planning system was used to fuse DWI scans and CT images to investigate the possibility of delineating GTV on fused images. The differences between the GTV length according to CT, T2-weighted MRI and pathology were 3.63 ± 12.06 mm and 3.46 ± 11.41 mm, respectively. When the diffusion-sensitive gradient b-value was 400, 600, and 800 s/mm 2 , the differences between the GTV length using DWI and pathology were 0.73 ± 6.09 mm, -0.54 ± 6.03 mm and −1.58 ± 5.71 mm, respectively. DWI scans and CT images were fused accurately using the radiotherapy planning system. GTV margins were depicted clearly on fused images. DWI displays esophageal SCC lengths most precisely when compared with CT or regular MRI. DWI scans fused with CT images can be used to improve accuracy to delineate GTV in esophageal SCC

  10. Intracranial metastatic mucinous adrenocarcinoma with characteristic features on diffusion-weighted imaging and in vivo magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Guruprasad, Ashwathnarayan S.; Chandrashekar, Hoskote S.; Jayakumar, Peruvumba N.; Srikanth, Subbamma G.; Shankar, Susarla K.

    2004-01-01

    Intracranial abscesses and metastases are common lesions that might not be differentiated on routine MR I alone. In vivo proton spectroscopy and diffusion-weighted imaging have been used as complementary investigations for improved tissue characterization. In the present report we illustrate the role of mucin and its contribution to signal characteristics on diffusion-weighted imaging in a metastatic mucinous adenocarcinoma Copyright (2004) Blackwell Publishing Asia Pty Ltd

  11. Role of apparent diffusion coefficients with diffusion-weighted magnetic resonance imaging in differentiating between benign and malignant bone tumors.

    Science.gov (United States)

    Wang, Tingting; Wu, Xiangru; Cui, Yanfen; Chu, Caiting; Ren, Gang; Li, Wenhua

    2014-11-29

    Benign and malignant bone tumors can present similar imaging features. This study aims to evaluate the significance of apparent diffusion coefficients (ADC) in differentiating between benign and malignant bone tumors. A total of 187 patients with 198 bone masses underwent diffusion-weighted (DW) magnetic resonance (MR) imaging. The ADC values in the solid components of the bone masses were assessed. Statistical differences between the mean ADC values in the different tumor types were determined by Student's t-test. Histological analysis showed that 84/198 (42.4%) of the bone masses were benign and 114/198 (57.6%) were malignant. There was a significant difference between the mean ADC values in the benign and malignant bone lesions (Pbenign and malignant bone tumors.

  12. Diffusion weighted imaging by MR method

    International Nuclear Information System (INIS)

    Horikawa, Yoshiharu; Naruse, Shoji; Ebisu, Toshihiko; Tokumitsu, Takuaki; Ueda, Satoshi; Tanaka, Chuzo; Higuchi, Toshihiro; Umeda, Masahiro.

    1993-01-01

    Diffusion weighted magnetic resonance imaging is a recently developed technique used to examine the micromovement of water molecules in vivo. We have applied this technique to examine various kinds of brain diseases, both experimentally and clinically. The calculated apparent diffusion coefficient (ADC) in vivo showed reliable values. In experimentally induced brain edema in rats, the pathophysiological difference of the type of edema (such as cytotoxic, and vasogenic) could be differentiated on the diffusion weighted MR images. Cytotoxic brain edema showed high intensity (slower diffusion) on the diffusion weighted images. On the other hand, vasogenic brain edema showed a low intensity image (faster diffusion). Diffusion anisotropy was demonstrated according to the direction of myelinated fibers and applied motion proving gradient (MPG). This anisotropy was also demonstrated in human brain tissue along the course of the corpus callosum, pyramidal tract and optic radiation. In brain ischemia cases, lesions were detected as high signal intensity areas, even one hour after the onset of ischemia. Diffusion was faster in brain tumor compared with normal brain. Histological differences were not clearly reflected by the ADC value. In epidermoid tumor cases, the intensity was characteristically high, was demonstrated, and the cerebrospinal fluid border was clearly demonstrated. New clinical information obtainable with this molecular diffusion method will prove to be useful in various clinical studies. (author)

  13. Diffusion-weighted MR imaging in leukodystrophies

    Energy Technology Data Exchange (ETDEWEB)

    Patay, Zoltan [King Faisal Specialist Hospital and Research Centre, Department of Radiology, Riyadh (Saudi Arabia)

    2005-11-01

    Leukodystrophies are genetically determined metabolic diseases, in which the underlying biochemical abnormality interferes with the normal build-up and/or maintenance of myelin, which leads to hypo- (or arrested) myelination, or dysmyelination with resultant demyelination. Although conventional magnetic resonance imaging has significantly contributed to recent progress in the diagnostic work-up of these diseases, diffusion-weighted imaging has the potential to further improve our understanding of underlying pathological processes and their dynamics through the assessment of normal and abnormal diffusion properties of cerebral white matter. Evaluation of conventional diffusion-weighted and ADC map images allows the detection of major diffusion abnormalities and the identification of various edema types, of which the so-called myelin edema is particularly relevant to leukodystrophies. Depending on the nature of histopathological changes, stage and progression gradient of diseases, various diffusion-weighted imaging patterns may be seen in leukodystrophies. Absent or low-grade myelin edema is found in mucopolysaccharidoses, GM gangliosidoses, Zellweger disease, adrenomyeloneuropathy, L-2-hydroxyglutaric aciduria, non-ketotic hyperglycinemia, classical phenylketonuria, Van der Knaap disease and the vanishing white matter, medium grade myelin edema in metachromatic leukodystrophy, X-linked adrenoleukodystrophy and HMG coenzyme lyase deficiency and high grade edema in Krabbe disease, Canavan disease, hyperhomocystinemias, maple syrup urine disease and leukodystrophy with brainstem and spinal cord involvement and high lactate. (orig.)

  14. Diffusion-weighted MR imaging in leukodystrophies

    International Nuclear Information System (INIS)

    Patay, Zoltan

    2005-01-01

    Leukodystrophies are genetically determined metabolic diseases, in which the underlying biochemical abnormality interferes with the normal build-up and/or maintenance of myelin, which leads to hypo- (or arrested) myelination, or dysmyelination with resultant demyelination. Although conventional magnetic resonance imaging has significantly contributed to recent progress in the diagnostic work-up of these diseases, diffusion-weighted imaging has the potential to further improve our understanding of underlying pathological processes and their dynamics through the assessment of normal and abnormal diffusion properties of cerebral white matter. Evaluation of conventional diffusion-weighted and ADC map images allows the detection of major diffusion abnormalities and the identification of various edema types, of which the so-called myelin edema is particularly relevant to leukodystrophies. Depending on the nature of histopathological changes, stage and progression gradient of diseases, various diffusion-weighted imaging patterns may be seen in leukodystrophies. Absent or low-grade myelin edema is found in mucopolysaccharidoses, GM gangliosidoses, Zellweger disease, adrenomyeloneuropathy, L-2-hydroxyglutaric aciduria, non-ketotic hyperglycinemia, classical phenylketonuria, Van der Knaap disease and the vanishing white matter, medium grade myelin edema in metachromatic leukodystrophy, X-linked adrenoleukodystrophy and HMG coenzyme lyase deficiency and high grade edema in Krabbe disease, Canavan disease, hyperhomocystinemias, maple syrup urine disease and leukodystrophy with brainstem and spinal cord involvement and high lactate. (orig.)

  15. The role of dynamic contrast-enhanced and diffusion weighted magnetic resonance imaging in the female pelvis

    Energy Technology Data Exchange (ETDEWEB)

    Sala, Evis, E-mail: es220@radiol.cam.ac.uk [University Department of Radiology, Box 218, Level 5, Addenbrooke' s Hospital, Hills Road, Cambridge CB2 0QQ (United Kingdom); Rockall, Andrea, E-mail: Andrea.Rockall@bartsandthelondon.nhs.uk [Department of Radiology, St Bartholomew' s Hospital, West Smithfield, London EC1A 7ED (United Kingdom); Rangarajan, Deepa, E-mail: rdrangarajan@googlemail.com [Department of Radiology, Box 218, Addenbrooke' s Hospital, Hills Road, Cambridge CB2 0QQ (United Kingdom); Kubik-Huch, Rahel A., E-mail: rahel.kubik@ksb.ch [Institute of Radiology, Department of Medical Services, Kantonsspital Baden Im Ergel, CH-5404 Baden (Switzerland)

    2010-12-15

    Functional imaging by means of dynamic multiphase contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted magnetic resonance imaging (DW-MRI) is now part of the standard imaging protocols for evaluation of the female pelvis. DCE-MRI and DW-MRI are important MR imaging techniques which enable the radiologist to move from morphological to functional assessment of diseases of the female pelvis. This is mainly due to the limitations of morphologic imaging, particularly in lesion characterization, accurate lymph node staging, assessment of tumour response and inability to differentiate post-treatment changes from tumour recurrence. DCE-MRI improves the accuracy of T2WI in staging of endometrial cancer. It also helps differentiate tumour recurrence from radiation fibrosis in patients with cervical cancer. DCE-MRI improves characterization of cystic adnexal lesions and detection of small peritoneal implants in patients with ovarian cancer. DW-MRI is valuable in preoperative staging of patients with endometrial and cervical cancer, especially in detection of extra-uterine disease. It does increase reader's confidence for detection of recurrent disease in gynaecological malignancies and improves detection of small peritoneal implants in patients with ovarian cancer. In this review article we give an overview of both DCE-MRI and DW-MRI techniques, concentrating on their main clinical application in the female pelvis, and present a practical approach of the added value of these techniques according to the main pathological conditions, highlighting the pearls and pitfalls of each technique.

  16. Multi-component fiber track modelling of diffusion-weighted magnetic resonance imaging data

    Directory of Open Access Journals (Sweden)

    Yasser M. Kadah

    2010-01-01

    Full Text Available In conventional diffusion tensor imaging (DTI based on magnetic resonance data, each voxel is assumed to contain a single component having diffusion properties that can be fully represented by a single tensor. Even though this assumption can be valid in some cases, the general case involves the mixing of components, resulting in significant deviation from the single tensor model. Hence, a strategy that allows the decomposition of data based on a mixture model has the potential of enhancing the diagnostic value of DTI. This project aims to work towards the development and experimental verification of a robust method for solving the problem of multi-component modelling of diffusion tensor imaging data. The new method demonstrates significant error reduction from the single-component model while maintaining practicality for clinical applications, obtaining more accurate Fiber tracking results.

  17. Pitfalls and Limitations of Diffusion-Weighted Magnetic Resonance Imaging in the Diagnosis of Urinary Bladder Cancer

    Directory of Open Access Journals (Sweden)

    Wei-Ching Lin

    2015-06-01

    Full Text Available Adequately selecting a therapeutic approach for bladder cancer depends on accurate grading and staging. Substantial inaccuracy of clinical staging with bimanual examination, cystoscopy, and transurethral resection of bladder tumor has facilitated the increasing utility of magnetic resonance imaging to evaluate bladder cancer. Diffusion-weighted imaging (DWI is a noninvasive functional magnetic resonance imaging technique. The high tissue contrast between cancers and surrounding tissues on DWI is derived from the difference of water molecules motion. DWI is potentially a useful tool for the detection, characterization, and staging of bladder cancers; it can also monitor posttreatment response and provide information on predicting tumor biophysical behaviors. Despite advancements in DWI techniques and the use of quantitative analysis to evaluate the apparent diffusion coefficient values, there are some inherent limitations in DWI interpretation related to relatively poor spatial resolution, lack of cancer specificity, and lack of standardized image acquisition protocols and data analysis procedures that restrict the application of DWI and reproducibility of apparent diffusion coefficient values. In addition, inadequate bladder distension, artifacts, thinness of bladder wall, cancerous mimickers of normal bladder wall and benign lesions, and variations in the manifestation of bladder cancer may interfere with diagnosis and monitoring of treatment. Recognition of these pitfalls and limitations can minimize their impact on image interpretation, and carefully applying the analyzed results and combining with pathologic grading and staging to clinical practice can contribute to the selection of an adequate treatment method to improve patient care.

  18. Pitfalls and Limitations of Diffusion-Weighted Magnetic Resonance Imaging in the Diagnosis of Urinary Bladder Cancer

    Science.gov (United States)

    Lin, Wei-Ching; Chen, Jeon-Hor

    2015-01-01

    Adequately selecting a therapeutic approach for bladder cancer depends on accurate grading and staging. Substantial inaccuracy of clinical staging with bimanual examination, cystoscopy, and transurethral resection of bladder tumor has facilitated the increasing utility of magnetic resonance imaging to evaluate bladder cancer. Diffusion-weighted imaging (DWI) is a noninvasive functional magnetic resonance imaging technique. The high tissue contrast between cancers and surrounding tissues on DWI is derived from the difference of water molecules motion. DWI is potentially a useful tool for the detection, characterization, and staging of bladder cancers; it can also monitor posttreatment response and provide information on predicting tumor biophysical behaviors. Despite advancements in DWI techniques and the use of quantitative analysis to evaluate the apparent diffusion coefficient values, there are some inherent limitations in DWI interpretation related to relatively poor spatial resolution, lack of cancer specificity, and lack of standardized image acquisition protocols and data analysis procedures that restrict the application of DWI and reproducibility of apparent diffusion coefficient values. In addition, inadequate bladder distension, artifacts, thinness of bladder wall, cancerous mimickers of normal bladder wall and benign lesions, and variations in the manifestation of bladder cancer may interfere with diagnosis and monitoring of treatment. Recognition of these pitfalls and limitations can minimize their impact on image interpretation, and carefully applying the analyzed results and combining with pathologic grading and staging to clinical practice can contribute to the selection of an adequate treatment method to improve patient care. PMID:26055180

  19. The application value of diffusion-weighted magnetic resonance imaging in gross tumor volume delineation of esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Hou Dongliang; Shi Gaofeng; Gao Xianshu

    2012-01-01

    Objective: To analyze the application value of diffusion-weighted magnetic resonance imaging (DWMRI) in gross tumor volume (GTV) delineation of esophageal squamous cell carcinoma (SCC). Methods: Twenty-nine patients with esophageal SCC treated with radical surgery were analyzed. Routine CT scan, MRI T 2 -weighted and DWMRI were employed before surgery; diffusion-sensitive gradient b-values were taken 400, 600 and 800 s/mm 2 . GTVs were delineated using CT, MRI T 2 -weighted images and DWMRI under different b-value images. The length of GTVs measured under different images was compared with the pathological length and confirm the most accurate imaging condition. Use radiotherapy planning system to fuse DWMRI images and CT images to investigate the possibility of delineate GTVs on fused images. Results: The difference of GTV length value between CT, T 2 WI images and specimen was 3.36 mm and 2.84 mm. When b =400,600 and 800 s/mm 2 , the difference between GTV length value on the DWMRI images and on specimen was 0.47 mm, -0.47 mm and - 1.53 mm; the correlation coefficient of the measuring esophageal lengths on DWMRI images and the pathological lengths was 0.928, 0.927 and 0.938. DWMRI images and CT images could fuse accurately on radiotherapy planning system. GTV margin could.show clearly on fused images. Conclusions: DWMRI images can display the esophageal carcinoma lengths and margin accurately. When DWMRI images fused with CT images, GTV margin could show clearly,it can be used to delineate GTV accurately. (authors)

  20. Diagnosis of acute ischemic stroke based on time-to-peak and diffusion-weighted magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Keisuke; Eguchi, Tsuneyoshi; Sora, Shigeo; Izumi, Masafumi; Hiyama, Hirofumi [Kameda General Hospital, Kamogawa, Chiba (Japan); Ueki, Keisuke [Tokyo Univ. (Japan). Hospital

    2002-07-01

    Rapid and accurate diagnosis of the hemodynamics of the brain is essential for the treatment of acute ischemic stroke. This study investigated whether time-to-peak and diffusion-weighted magnetic resonance (MR) imaging are useful for predicting the course of stroke. Fourteen patients with non-lacunar acute ischemic stroke underwent emergent MR imaging within 24 hours from the onset followed by cerebral angiography and xenon-enhanced computed tomography (CT). Serial CT was obtained to monitor changes in the size and nature of the infarct. Volumes of the abnormal lesions demonstrated on time-to-peak (V{sub T}) or diffusion-weighted (V{sub D}) images were measured, and the ratio of V{sub T} to V{sub D} was calculated. Based on this ratio, patients were classified into three groups: Group 1 (V{sub T}/V{sub D} 0.5-1.5, n=9), Group 2 (V{sub T}/V{sub D}>1.5, n=3), and Group 3 (V{sub T}/V{sub D}<0.5, n=2). The size of the infarct detected as a low-density area on serial CT scans did not change significantly throughout the course in Group 1 patients, but showed enlargement in all three patients in Group 2. Two patients in Group 3 had major trunk occlusion followed by spontaneous reperfusion, and both developed hemorrhagic transformation. Our study showed that classification of ischemic stroke based on the V{sub T}/V{sub D} ratio was predictive of the time course of the infarct, and may be useful in selecting the initial therapeutic procedure immediately after the onset of stroke. (author)

  1. Diffusion-weighted imaging and magnetic resonance proton spectroscopy following preterm birth

    International Nuclear Information System (INIS)

    Hart, A.R.; Smith, M.F.; Whitby, E.H.; Alladi, S.; Wilkinson, S.; Paley, M.N.; Griffiths, P.D.

    2014-01-01

    Aim: To study the associations between magnetic resonance proton spectroscopy (MRS) data and apparent diffusion coefficients (ADC) from the preterm brain with developmental outcome at 18 months corrected age and clinical variables. Materials and methods: A prospective observational cohort study of 67 infants born before 35 weeks gestational age who received both magnetic resonance imaging of the brain between 37 and 44 weeks corrected gestational age and developmental assessment around 18 months corrected age. Results: No relationships were found between ADC values and MRS results or outcome. MRS ratios involving N-acetyl aspartate (NAA) from the posterior white matter were associated with ''severe'' and ''moderate to severe'' difficulties, and fine motor scores were significantly lower in participants with a visible lactate doublet in the posterior white matter. The presence of a patent ductus arteriosus (PDA) was the only clinical factor related to NAA ratios. Conclusion: Altered NAA levels in the posterior white matter may reflect subtle white matter injury associated with neuro-developmental difficulties, which may be related to a PDA. Further work is needed to assess the longer-term neuro-developmental implications of these findings, and to study the effect of PDAs on developmental outcome in later childhood/adolescence. - Highlights: • ADC values around term corrected age from a wide area of the brain are not associated with developmental outcome. • NAA ratios from the posterior white matter are associated with adverse outcome. • No relationship between MRS data and ADC values exist when measured from the same region of the cerebral white matter. • The presence of a patent ductus arterious was associated with NAA ratios from the posterior white matter, but not outcome

  2. Value of diffusion - weighted magnetic resonance imaging in the assessment of bone marrow in vertebral metastases

    International Nuclear Information System (INIS)

    Herneth, A.M.; Philipp, M.; Trattnig, S.; Imhof, H.; Naude, J.; Beichel, R.

    2000-01-01

    Aim of the study. The aim of the study was the evaluation of the diffusion coefficient (ADC) of vertebral metastasis and regular vertebral bodies with diffusion weighted MRI (DWI). DWI evaluates the tissue-specific molecular diffusion of protons. In tissues with high cell densities (neoplasm) a decreased ADC can be expected due to restricted diffusion according to an exaggerated amount of intra- and intercellular membranes (i.e. diffusion barriers). Methods. In 5 breast cancer patients the ADC of both known vertebral metastases and of adjacent regular vertebral bodies were measured with DWI (1.0 T; Phased-Array-Body-Coil; b: 880 and 440 s/mm 2 ). Results. The ADC of regular vertebral bodies (1.3±0.23x10 -3 s/mm 2 ) was significantly (p -3 s/mm 2 ). Conclusions. These data demonstrate that the ADC can be reliably measured in vertebral bodies. The quantitative evaluation of the ADC in vertebral bodies seems to be an objective and comparable parameter for differentiating malign from benign vertebral tissue. (orig.) [de

  3. Diffusion-weighted magnetic resonance imaging of borderzone necrosis in paediatric tuberculous meningitis

    International Nuclear Information System (INIS)

    Omar, Nadir; Pienaar, Manana; Andronikou, Savvas; Van Toorn, Ronald

    2011-01-01

    Tuberculous meningitis (TBM) is associated with borderzone necrosis (BZN) of the brain parenchyma in areas adjacent to meningeal inflammation. Diffusion-weighted MRI (DWI) allows for accurate detection of cytotoxic oedema associated with necrosis. Detection and characterisation of BZN using DWI to explain its pathogenesis in TBM have not been performed previously in children. Our objective was to identify the prevalence and characteristics of BZN using DWI in children with TBM and to correlate it with the presence, degree and distribution of basal meningeal enhancement (BE) in the absence of large-vessel thrombosis. A retrospective descriptive MRI DWI study of 34 children with TBM was conducted. The topography of BZN was compared with the presence and severity of BE on specific MRI sequences. BZN was identified on MRI DWI in 50% of patients of which 82% had involvement of the temporal lobes. The severity and extent of BE in either middle cerebral artery cistern correlated with the presence of BZN (P = 0.02). BZN did not correlate with radiologically detectable vascular occlusion BZN is common in TBM occurring in 50% of children. Detection and confirmation of cytotoxic oedema associated with BZN using DWI, and its clear relation to BE supports existing pathogenetic descriptions. The pathogenesis of BZN differs to that of topographical infarction on the basis of distribution as well as an absent statistical relationship between vascular occlusion and BZN.

  4. Added value of diffusion-weighted magnetic resonance imaging for the detection of pancreatic fluid collection infection

    Energy Technology Data Exchange (ETDEWEB)

    Borens, Bruno [Polyclinique Santa Maria, Nice (France); Arvanitakis, Marianna; Eisendrath, Pierre; Toussaint, Emmanuel; Deviere, Jacques [Erasme Hospital, Department of Gastroenterology, Brussels (Belgium); Absil, Julie; Matos, Celso; Bali, Maria Antonietta [Erasme Hospital, Department of Radiology, Brussels (Belgium); El Bouchaibi, Said [Epicura, Ath (Belgium)

    2017-03-15

    To investigate the added value of diffusion-weighted (DW) magnetic resonance (MR) imaging in the detection of infection in pancreatic fluid collections (PFC). Forty-patients with PFC requiring endoscopic-transmural drainage underwent conventional-MR and DW-MR imaging (b = 1000 s/mm{sup 2}) before endoscopy. MR images were divided into two sets (set1, conventional-MR; set2, conventional-MR, DW-MR and ADC maps) and randomized. Two independent readers performed qualitative and quantitative (apparent diffusion coefficient, ADC) image analysis. Bacteriological analysis of PFC content was the gold standard. Non-parametric tests were used for comparisons. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy were calculated for the two sets for both readers. Receiver operating characteristic curves (ROC) were drawn to assess quantitative DW-MR imaging diagnostic performance. For both readers, sensitivity, specificity, NPV, PPV and accuracy for infected PFCs were higher for set2 (P >.05). ADC were lower in infected versus non-infected PFCs (P ≤.031). Minimum ADC cut-off: 1,090 x 10{sup -3} mm{sup 2}/s for reader 1 and 1,012 x 10{sup -3} mm{sup 2}/s for reader 2 (sensitivity and specificity 67 % and 96 % for both readers). Qualitative information provided by DW-MR may help to assess PFCs infection. Infected PFCs show significantly lower ADCs compared to non-infected ones. (orig.)

  5. Added value of diffusion-weighted magnetic resonance imaging for the detection of pancreatic fluid collection infection

    International Nuclear Information System (INIS)

    Borens, Bruno; Arvanitakis, Marianna; Eisendrath, Pierre; Toussaint, Emmanuel; Deviere, Jacques; Absil, Julie; Matos, Celso; Bali, Maria Antonietta; El Bouchaibi, Said

    2017-01-01

    To investigate the added value of diffusion-weighted (DW) magnetic resonance (MR) imaging in the detection of infection in pancreatic fluid collections (PFC). Forty-patients with PFC requiring endoscopic-transmural drainage underwent conventional-MR and DW-MR imaging (b = 1000 s/mm"2) before endoscopy. MR images were divided into two sets (set1, conventional-MR; set2, conventional-MR, DW-MR and ADC maps) and randomized. Two independent readers performed qualitative and quantitative (apparent diffusion coefficient, ADC) image analysis. Bacteriological analysis of PFC content was the gold standard. Non-parametric tests were used for comparisons. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy were calculated for the two sets for both readers. Receiver operating characteristic curves (ROC) were drawn to assess quantitative DW-MR imaging diagnostic performance. For both readers, sensitivity, specificity, NPV, PPV and accuracy for infected PFCs were higher for set2 (P >.05). ADC were lower in infected versus non-infected PFCs (P ≤.031). Minimum ADC cut-off: 1,090 x 10"-"3 mm"2/s for reader 1 and 1,012 x 10"-"3 mm"2/s for reader 2 (sensitivity and specificity 67 % and 96 % for both readers). Qualitative information provided by DW-MR may help to assess PFCs infection. Infected PFCs show significantly lower ADCs compared to non-infected ones. (orig.)

  6. Does non-echo-planar diffusion-weighted magnetic resonance imaging have a role in assisting the clinical diagnosis of cholesteatoma in selected cases?

    Science.gov (United States)

    Nash, R; Lingam, R K; Chandrasekharan, D; Singh, A

    2018-03-01

    To determine the diagnostic performance of diffusion-weighted magnetic resonance imaging in the assessment of patients with suspected, but not clinically evident, cholesteatoma. A retrospective analysis of a prospectively collected database of non-echo-planar diffusion-weighted magnetic resonance imaging studies (using a half-Fourier single-shot turbo-spin echo sequence) was conducted. Clinical records were retrospectively reviewed to determine indications for imaging and operative findings. Seventy-eight investigations in 74 patients with suspected cholesteatoma aged 5.7-79.2 years (mean, 41.7 years) were identified. Operative confirmation was available in 44 ears. Diagnostic accuracy of the imaging technique was calculated using operative findings as a 'gold standard'. Sensitivity of the investigation was examined via comparison with clinically evident cholesteatoma. The accuracy of diffusion-weighted magnetic resonance imaging in assessment of suspected cholesteatoma was 63.6 per cent. The imaging technique was significantly less accurate in assessment of suspected cholesteatoma than clinically evident disease (p < 0.001). Computed tomography and diffusion-weighted magnetic resonance imaging may be complementary in assessment of suspected cholesteatoma, but should be used with caution, and clinical judgement is paramount.

  7. Diffusion-Weighted Magnetic Resonance Imaging of Urinary Epithelial Cancer with Upper Urinary Tract Obstruction: Preliminary Results

    International Nuclear Information System (INIS)

    Takeuchi, M.; Matsuzaki, K.; Kubo, H.; Nishitani, H.

    2008-01-01

    Background: Various malignant tumors of the body show high signal intensity on diffusion-weighted magnetic resonance imaging (DWI). In the genitourinary region, DWI is expected to have a role in detecting urinary epithelial cancer noninvasively. Purpose: To demonstrate the feasibility of DWI for the diagnosis of urinary epithelial cancer with upper urinary tract obstruction. Material and Methods: Twenty upper urinary tract cancers in 16 patients were evaluated by high-b-value DWI (b=800s/mm2). The signal intensity was visually evaluated, and the apparent diffusion coefficients (ADCs) were measured. Results: All urinary epithelial cancers showed high signal intensity on DWI. The ADC in cancerous lesions was 1.31±0.27 x 10 -3 mm 2 /s, which was significantly lower than that of the lumens of the ureter or renal pelvis (3.32±0.44 x 10 -3 mm 2 /s; P<0.001). Maximum intensity projection images of DWI in combination with static-fluid MR urography provided three-dimensional entire urinary tract imaging with the extension of tumors. Conclusion: DWI is useful in the tumor detection and in evaluating the tumor extension of urinary epithelial cancer in patients with upper urinary tract obstruction

  8. The Role of Diffusion-Weighted Magnetic Resonance Imaging in the ...

    African Journals Online (AJOL)

    2018-02-23

    Feb 23, 2018 ... Imaging in the Differential Diagnosis of Simple and Hydatid Cysts of the. Liver. Niger J Clin .... the ADC mapping, the size of the region of interest. (ROI) was chosen as .... from simple one. Financial support and sponsorship.

  9. Evolution of Diffusion-Weighted Magnetic Resonance Imaging Signal Abnormality in Sporadic Creutzfeldt-Jakob Disease, With Histopathological Correlation.

    Science.gov (United States)

    Eisenmenger, Laura; Porter, Marie-Claire; Carswell, Christopher J; Thompson, Andrew; Mead, Simon; Rudge, Peter; Collinge, John; Brandner, Sebastian; Jäger, Hans R; Hyare, Harpreet

    2016-01-01

    Prion diseases represent the archetype of brain diseases caused by protein misfolding, with the most common subtype being sporadic Creutzfeldt-Jakob disease (sCJD), a rapidly progressive dementia. Diffusion-weighted imaging (DWI) has emerged as the most sensitive magnetic resonance imaging (MRI) sequence for the diagnosis of sCJD, but few studies have assessed the evolution of MRI signal as the disease progresses. To assess the natural history of the MRI signal abnormalities on DWI in sCJD to improve our understanding of the pathogenesis and to investigate the potential of DWI as a biomarker of disease progression, with histopathological correlation. Gray matter involvement on DWI was assessed among 37 patients with sCJD in 26 cortical and 5 subcortical subdivisions per hemisphere using a semiquantitative scoring system of 0 to 2 at baseline and follow-up. A total brain score was calculated as the summed scores in the individual regions. In 7 patients, serial mean diffusivity measurements were obtained. Age at baseline MRI, disease duration, atrophy, codon 129 methionine valine polymorphism, Medical Research Council Rating Scale score, and histopathological findings were documented. The study setting was the National Prion Clinic, London, England. All participants had a probable or definite diagnosis of sCJD and had at least 2 MRI studies performed during the course of their illness. The study dates were October 1, 2008 to April 1, 2012. The dates of our analysis were January 19 to April 20, 2012. Correlation of regional and total brain scores with disease duration. Among the 37 patients with sCJD in this study there was a significant increase in the number of regions demonstrating signal abnormality during the study period, with 59 of 62 regions showing increased signal intensity (SI) at follow-up, most substantially in the caudate and putamen (P disease duration (r = 0.47, P = .003 at baseline and r = 0.35, P = .03 at follow-up), and the left

  10. Diffusion-weighted Imaging Is a Sensitive and Specific Magnetic Resonance Sequence in the Diagnosis of Ankylosing Spondylitis.

    Science.gov (United States)

    Bradbury, Linda A; Hollis, Kelly A; Gautier, Benoît; Shankaranarayana, Sateesh; Robinson, Philip C; Saad, Nivene; Lê Cao, Kim-Anh; Brown, Matthew A

    2018-06-01

    We tested the discriminatory capacity of diffusion-weighted magnetic resonance imaging (DWI) and its potential as an objective measure of treatment response to tumor necrosis factor inhibition in ankylosing spondylitis (AS). Three cohorts were studied prospectively: (1) 18 AS patients with Bath Ankylosing Spondylitis Disease Activity Index > 4, and erythrocyte sedimentation rate > 25 and/or C-reactive protein > 10 meeting the modified New York criteria for AS; (2) 20 cases of nonradiographic axial spondyloarthritis (nr-axSpA) as defined by the Assessment of Spondyloarthritis international Society (ASAS) criteria; and (3) 20 non-AS patients with chronic low back pain, aged between 18 and 45 years, who did not meet the imaging arm of the ASAS criteria for axSpA. Group 1 patients were studied prior to and following adalimumab treatment. Patients were assessed by DWI and conventional magnetic resonance imaging (MRI), and standard nonimaging measures. At baseline, in contrast to standard nonimaging measures, DWI apparent diffusion coefficient (ADC) values showed good discriminatory performance [area under the curve (AUC) > 80% for Group 1 or 2 compared with Group 3]. DWI ADC values were significantly lower posttreatment (0.45 ± 0.433 before, 0.154 ± 0.23 after, p = 0.0017), but had modest discriminating capacity comparing pre- and posttreatment measures (AUC = 68%). This performance was similar to the manual Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system. DWI is informative for diagnosis of AS and nr-axSpA, and has moderate utility in assessment of disease activity or treatment response, with performance similar to that of the SPARCC MRI score.

  11. Diffusion-weighted magnetic resonance imaging for prediction of insignificant prostate cancer in potential candidates for active surveillance

    International Nuclear Information System (INIS)

    Kim, Tae Heon; Jeong, Jae Yong; Lee, Sin Woo; Sung, Hyun Hwan; Jeon, Hwang Gyun; Jeong, Byong Chang; Seo, Seong Il; Lee, Hyun Moo; Choi, Han Yong; Jeon, Seong Soo; Kim, Chan Kyo; Park, Byung Kwan

    2015-01-01

    To investigate whether the apparent diffusion coefficient (ADC) from diffusion-weighted magnetic resonance imaging (DW-MRI) could help improve the prediction of insignificant prostate cancer in candidates for active surveillance (AS). Enrolled in this retrospective study were 287 AS candidates who underwent DW-MRI before radical prostatectomy. Patients were stratified into two groups; Group A consisted of patients with no visible tumour or a suspected tumour ADC value > 0.830 x 10 -3 mm 2 /sec and Group B consisted of patients with a suspected tumour ADC value < 0.830 x 10 -3 mm 2 /sec. We compared pathological outcomes in each group. Group A had 243 (84.7 %) patients and Group B had 44 (15.3 %) patients. The proportion of organ-confined Gleason ≤ 6 disease and insignificant prostate cancer was significantly higher in Group A than Group B (61.3 % vs. 38.6 %, p = 0.005 and 47.7 % vs. 25.0 %, p = 0.005, respectively). On multivariate analysis, a high ADC value was the independent predictor of organ-confined Gleason ≤ 6 disease and insignificant prostate cancer (odds ratio = 2.43, p = 0.011 and odds ratio = 2.74, p = 0.009, respectively). Tumour ADC values may be a useful marker for predicting insignificant prostate cancer in candidates for AS. (orig.)

  12. Comparison of magnetic resonance elastography and diffusion-weighted imaging for differentiating benign and malignant liver lesions.

    Science.gov (United States)

    Hennedige, Tiffany P; Hallinan, James Thomas Patrick Decourcy; Leung, Fiona P; Teo, Lynette Li San; Iyer, Sridhar; Wang, Gang; Chang, Stephen; Madhavan, Krishna Kumar; Wee, Aileen; Venkatesh, Sudhakar K

    2016-02-01

    Comparison of magnetic resonance elastography (MRE) and diffusion-weighted imaging (DWI) for differentiating malignant and benign focal liver lesions (FLLs). Seventy-nine subjects with 124 FLLs (44 benign and 80 malignant) underwent both MRE and DWI. MRE was performed with a modified gradient-echo sequence and DWI with a free breathing technique (b = 0.500). Apparent diffusion coefficient (ADC) maps and stiffness maps were generated. FLL mean stiffness and ADC values were obtained by placing regions of interest over the FLLs on stiffness and ADC maps. The accuracy of MRE and DWI for differentiation of benign and malignant FLL was compared using receiver operating curve (ROC) analysis. There was a significant negative correlation between stiffness and ADC (r = -0.54, p 4.54kPa) and DWI (cut-off, benign and malignant FLLs. • MRE is superior to DWI for differentiating benign and malignant focal liver lesions. • Benign lesions with large fibrous components may have higher stiffness with MRE. • Cholangiocarcinomas tend to have higher stiffness than hepatocellular carcinomas. • Hepatocellular adenomas tend to have lower stiffness than focal nodular hyperplasia. • MRE is superior to conventional MRI in differentiating benign and malignant liver lesions.

  13. Quantitative analysis of diffusion-weighted magnetic resonance imaging in malignant breast lesions using different b value combinations

    Energy Technology Data Exchange (ETDEWEB)

    Nilsen, Line B. [Oslo University Hospital, Department of Radiation Biology, Norwegian Radium Hospital, P.O. Box 4959, Oslo (Norway); University of Oslo, Faculty of Medicine, P.O. Box 1078, Oslo (Norway); Fangberget, Anne [Oslo University Hospital, Department of Radiology and Nuclear Medicine, Division of Diagnostics and Intervention, Norwegian Radium Hospital, P.O. Box 4959, Oslo (Norway); Geier, Oliver [Oslo University Hospital, Department of Diagnostic Physics, The Interventional Centre, Division of Diagnostics and Intervention, P.O. Box 4950, Oslo (Norway); Seierstad, Therese [Oslo University Hospital, Department of Radiology and Nuclear Medicine, Division of Diagnostics and Intervention, Norwegian Radium Hospital, P.O. Box 4959, Oslo (Norway); Buskerud University College, Department of Health Sciences, P.O. Box 7053, Drammen (Norway)

    2013-04-15

    To explore how apparent diffusion coefficients (ADCs) in malignant breast lesions are affected by selection of b values in the monoexponential model and to compare ADCs with diffusion coefficients (Ds) obtained from the biexponential model. Twenty-four women (mean age 51.3 years) with locally advanced breast cancer were included in this study. Pre-treatment diffusion-weighted magnetic resonance imaging was performed using a 1.5-T system with b values of 0, 50, 100, 250 and 800 s/mm{sup 2}. Thirteen different b value combinations were used to derive individual monoexponential ADC maps. All b values were used in the biexponential model. Median ADC (including all b values) and D were 1.04 x 10{sup -3} mm{sup 2}/s (range 0.82-1.61 x 10{sup -3} mm{sup 2}/s) and 0.84 x 10{sup -3} mm{sup 2}/s (range 0.17-1.56 x 10{sup -3} mm{sup 2}/s), respectively. There was a strong positive correlation between ADCs and Ds. For clinically relevant b value combinations, maximum deviation between ADCs including and excluding low b values (<100 s/mm{sup 2}) was 11.8 %. Selection of b values strongly affects ADCs of malignant breast lesions. However, by excluding low b values, ADCs approach biexponential Ds, demonstrating that microperfusion influences the diffusion signal. Thus, care should be taken when ADC calculation includes low b values. (orig.)

  14. A reliability assessment of constrained spherical deconvolution-based diffusion-weighted magnetic resonance imaging in individuals with chronic stroke.

    Science.gov (United States)

    Snow, Nicholas J; Peters, Sue; Borich, Michael R; Shirzad, Navid; Auriat, Angela M; Hayward, Kathryn S; Boyd, Lara A

    2016-01-15

    Diffusion-weighted magnetic resonance imaging (DW-MRI) is commonly used to assess white matter properties after stroke. Novel work is utilizing constrained spherical deconvolution (CSD) to estimate complex intra-voxel fiber architecture unaccounted for with tensor-based fiber tractography. However, the reliability of CSD-based tractography has not been established in people with chronic stroke. Establishing the reliability of CSD-based DW-MRI in chronic stroke. High-resolution DW-MRI was performed in ten adults with chronic stroke during two separate sessions. Deterministic region of interest-based fiber tractography using CSD was performed by two raters. Mean fractional anisotropy (FA), apparent diffusion coefficient (ADC), tract number, and tract volume were extracted from reconstructed fiber pathways in the corticospinal tract (CST) and superior longitudinal fasciculus (SLF). Callosal fiber pathways connecting the primary motor cortices were also evaluated. Inter-rater and test-retest reliability were determined by intra-class correlation coefficients (ICCs). ICCs revealed excellent reliability for FA and ADC in ipsilesional (0.86-1.00; preliability for all metrics in callosal fibers (0.85-1.00; preliable approach to evaluate FA and ADC in major white matter pathways, in chronic stroke. Future work should address the reproducibility and utility of CSD-based metrics of tract number and tract volume. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A prospective study of diffusion weighted magnetic resonance imaging abnormalities in patients with cluster of seizures and status epilepticus.

    Science.gov (United States)

    Jabeen, S A; Cherukuri, Pavankumar; Mridula, Rukmini; Harshavardhana, K R; Gaddamanugu, Padmaja; Sarva, Sailaja; Meena, A K; Borgohain, Rupam; Jyotsna Rani, Y

    2017-04-01

    To study the frequency, imaging characteristics, and clinical predictors for development of periictal diffusion weighted MRI abnormalities. We prospectively analyzed electro clinical and imaging characteristic of adult patients with cluster of seizures or status epilepticus between November 2013 and November 2015, in whom the diffusion weighted imaging was done within 24h after the end of last seizure (clinical or electrographic). There were thirty patients who fulfilled the inclusion and exclusion criteria. Twenty patients (66%) had periictal MRI abnormalities. Nine patients (34%) did not have any MRI abnormality. All the patients with PMA had abnormalities on diffusion weighted imaging (DWI). Hippocampal abnormalities were seen in nine (53%), perisylvian in two (11.7%), thalamic in five (30%), splenium involvement in two (11.7%) and cortical involvement (temporo-occipital, parieto-occipital, temporo-parietal, fronto-parietal and fronto-temporal) in sixteen (94.1%) patients. Complete reversal of DWI changes was noted in sixteen (80%) patients and four (20%) patients showed partial resolution of MRI abnormalities. Mean duration of seizures was significantly higher among patients with PMA (59.11+20.97h) compared to those without MRI changes (27.33+9.33h) (pstatus epilepticus and were highly concordant with clinical semiology and EEG activity. Patients with longer duration of seizures/status were more likely to have PMA. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Diffusion-weighted magnetic resonance imaging for the detection of lipid-rich necrotic core in carotid atheroma in vivo

    International Nuclear Information System (INIS)

    Young, Victoria Eleanor; Patterson, Andrew J.; Sadat, Umar; Bowden, David J.; Tang, Tjun Y.; Gillard, Jonathan H.; Graves, Martin J.; Priest, Andrew N.; Skepper, Jeremy N.; Kirkpatrick, Peter J.

    2010-01-01

    Research has shown that knowing the morphology of carotid atheroma improves current risk stratification for predicting subsequent thrombo-embolic events. Previous magnetic resonance (MR) ex vivo studies have shown that diffusion-weighted imaging (DWI) can detect lipid-rich necrotic core (LR/NC) and fibrous cap. This study aims to establish if this is achievable in vivo. Twenty-six patients (mean age 73 years, range 54-87 years) with moderate to severe carotid stenosis confirmed on ultrasound were imaged. An echo-planar DWI sequence was performed along with standard high-resolution MR imaging. Apparent diffusion coefficient (ADC) maps were evaluated. Two independent readers reported the mean ADC values from regions of interest defining LR/NCs and fibrous caps. For subjects undergoing carotid endarterectomy (n = 19), carotid specimens were obtained and stained using Nile red. The mean ADC values were 1.0 x 10 -3 mm 2 /s (±SD 0.3 x 10 -3 mm 2 /s) and 0.7 x 10 -3 mm 2 /s (±SD 0.2 x 10 -3 mm 2 /s) for fibrous cap and LR/NC, respectively; the difference was significant (p < 0.0001). The intra-class correlation coefficients summarising the agreement between the two independent readers were 0.84 and 0.60 for fibrous cap and LR/NC, respectively. Comparison of quantitative ADC values and histology (by subjective grading of lipid content) showed a significant correlation: heavier lipid staining matched lower ADC values (r = -0.435, p = 0.005). This study indicates that DWI can be used to distinguish LR/NC and the fibrous cap. The study also suggests that the mean ADC value may be linearly related to subjective graded LR/NC content determined by histology. (orig.)

  17. Diffusion-weighted magnetic resonance imaging for the detection of lipid-rich necrotic core in carotid atheroma in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Young, Victoria Eleanor; Patterson, Andrew J.; Sadat, Umar; Bowden, David J.; Tang, Tjun Y.; Gillard, Jonathan H. [Addenbrooke' s Hospital, University Department of Radiology, Box 218, Cambridge (United Kingdom); Graves, Martin J.; Priest, Andrew N. [Addenbrooke' s Hospital, University Department of Radiology, Box 218, Cambridge (United Kingdom); Addenbrooke' s Hospital, Department of Medical Physics, Cambridge (United Kingdom); Skepper, Jeremy N. [University of Cambridge, Multi-imaging Centre, Cambridge (United Kingdom); Kirkpatrick, Peter J. [Addenbrooke' s Hospital, Department of Neurosurgery, Cambridge (United Kingdom)

    2010-10-15

    Research has shown that knowing the morphology of carotid atheroma improves current risk stratification for predicting subsequent thrombo-embolic events. Previous magnetic resonance (MR) ex vivo studies have shown that diffusion-weighted imaging (DWI) can detect lipid-rich necrotic core (LR/NC) and fibrous cap. This study aims to establish if this is achievable in vivo. Twenty-six patients (mean age 73 years, range 54-87 years) with moderate to severe carotid stenosis confirmed on ultrasound were imaged. An echo-planar DWI sequence was performed along with standard high-resolution MR imaging. Apparent diffusion coefficient (ADC) maps were evaluated. Two independent readers reported the mean ADC values from regions of interest defining LR/NCs and fibrous caps. For subjects undergoing carotid endarterectomy (n = 19), carotid specimens were obtained and stained using Nile red. The mean ADC values were 1.0 x 10{sup -3} mm{sup 2}/s ({+-}SD 0.3 x 10{sup -3} mm{sup 2}/s) and 0.7 x 10{sup -3} mm{sup 2}/s ({+-}SD 0.2 x 10{sup -3} mm{sup 2}/s) for fibrous cap and LR/NC, respectively; the difference was significant (p < 0.0001). The intra-class correlation coefficients summarising the agreement between the two independent readers were 0.84 and 0.60 for fibrous cap and LR/NC, respectively. Comparison of quantitative ADC values and histology (by subjective grading of lipid content) showed a significant correlation: heavier lipid staining matched lower ADC values (r = -0.435, p = 0.005). This study indicates that DWI can be used to distinguish LR/NC and the fibrous cap. The study also suggests that the mean ADC value may be linearly related to subjective graded LR/NC content determined by histology. (orig.)

  18. Diffusion-weighted magnetic resonance imaging: a potential non-invasive marker of tumour aggressiveness in localized prostate cancer

    International Nuclear Information System (INIS)

    Souza, N.M. de; Riches, S.F.; Van As, N.J.; Morgan, V.A.; Ashley, S.A.; Fisher, C.; Payne, G.S.; Parker, C.

    2008-01-01

    Aim: To evaluate diffusion-weighted magnetic resonance imaging (DW-MRI) as a marker for disease aggressiveness by comparing tumour apparent diffusion coefficients (ADCs) between patients with low- versus higher-risk localized prostate cancer. Method: Forty-four consecutive patients classified as low- [n = 26, stageT1/T2a, Gleason score ≤ 6, prostate-specific antigen (PSA) 10 (group 2)] risk, who subsequently were monitored with active surveillance or started neoadjuvant hormone and radiotherapy, respectively, underwent endorectal MRI. T2-weighted (T2W) and DW images (5 b values, 0-800 s/mm 2 ) were acquired and isotropic ADC maps generated. Regions of interest (ROIs) on T2W axial images [around whole prostate, central gland (CG), and tumour] were transferred to ADC maps. Tumour, CG, and peripheral zone (PZ = whole prostate minus CG and tumour) ADCs (fast component from b = 0-100 s/mm 2 , slow component from b = 100-800 s/mm 2 ) were compared. Results: T2W-defined tumour volume medians, and quartiles were 1.2 cm 3 , 0.7 and 3.3 cm 3 (group 1); and 6 cm 3 , 1.3 and 16.5 cm 3 (group 2). There were significant differences in both ADC fast (1778 ± 264 x 10 -6 versus 1583 ± 283 x 10 -6 mm 2 /s, p = 0.03) and ADC slow (1379 ± 321 x 10 -6 versus 1196 ± 158 x 10 -6 mm 2 /s, p = 0.001) between groups. Tumour volume (p = 0.002) and ADC slow (p = 0.005) were significant differentiators of risk group. Conclusion: Significant differences in tumour ADCs exist between patients with low-risk, and those with higher-risk localized prostate cancer. DW-MRI merits further study with respect to clinical outcomes

  19. Early detection of neuropathophysiology using diffusion-weighted magnetic resonance imaging in asymptomatic cats with feline immunodeficiency viral infection.

    Science.gov (United States)

    Bucy, Daniel S; Brown, Mark S; Bielefeldt-Ohmann, Helle; Thompson, Jesse; Bachand, Annette M; Morges, Michelle; Elder, John H; Vandewoude, Sue; Kraft, Susan L

    2011-08-01

    HIV infection results in a highly prevalent syndrome of cognitive and motor disorders designated as HIV-associated dementia (HAD). Neurologic dysfunction resembling HAD has been documented in cats infected with strain PPR of the feline immunodeficiency virus (FIV), whereas another highly pathogenic strain (C36) has not been known to cause neurologic signs. Animals experimentally infected with equivalent doses of FIV-C36 or FIV-PPR, and uninfected controls were evaluated by magnetic resonance diffusion-weighted imaging (DW-MRI) and spectroscopy (MRS) at 17.5-18 weeks post-infection, as part of a study of viral clade pathogenesis in FIV-infected cats. The goals of the MR imaging portion of the project were to determine whether this methodology was capable of detecting early neuropathophysiology in the absence of outward manifestation of neurological signs and to compare the MR imaging results for the two viral strains expected to have differing degrees of neurologic effects. We hypothesized that there would be increased diffusion, evidenced by the apparent diffusion coefficient as measured by DW-MRI, and altered metabolite ratios measured by MRS, in the brains of FIV-PPR-infected cats relative to C36-infected cats and uninfected controls. Increased apparent diffusion coefficients were seen in the white matter, gray matter, and basal ganglia of both the PPR and C36-infected (asymptomatic) cats. Thalamic MRS metabolite ratios did not differ between groups. The equivalently increased diffusion by DW-MRI suggests similar indirect neurotoxicity mechanisms for the two viral genotypes. DW-MRI is a sensitive tool to detect neuropathophysiological changes in vivo that could be useful during longitudinal studies of FIV.

  20. Utility of Diffusion Weighted Magnetic Resonance Imaging with Multiple B Values in Evaluation of Pancreatic Malignant and Benign Lesions and Pancreatitis.

    Science.gov (United States)

    Karadeli, Elif; Erbay, Gurcan; Parlakgumus, Alper; Koc, Zafer

    2018-02-01

    To determine the feasibility of diffusion-weighted imaging in evaluation of pancreatic lesions and in differentiation of benign from malignant lesions. Descriptive study. Baskent University Adana Teaching and Research Center, Adana, Turkey, between September 2013 and May 2015. Forty-three lesions [pancreas adenocarcinoma (n=25)], pancreatitis (n=10), benign lesion (n=8)] were utilized with diffusion-weighted magnetic resonance imaging with multiple b-values. Different ADC maps of diffusion weighted images by using b-values were acquired. The median ADC at all b values for malignant lesions was significantly different from that for benign lesions (pvalues were compared between benign lesions/normal parenchyma and malignant lesions/normal parenchyma, there was a significant statistical difference in all b values between benign and malignant lesions except at b 50 and b 200 (pvalue (AUC=0.804) was more effective than the lesion ADC for b 600 value (AUC=0.766) in differentiation of benign and malignant lesions. The specificity and sensitivity of the lesion/normal parenchyma ADC ratio were higher than those of ADC values of lesions. When the ADC was compared between benign lesions and pancreatitis, a significant difference was found at all b values (pvalue combinations (p>0.05). Diffusion-weighted magnetic resonance images can be helpful in differentiation of pancreatic carcinoma and benign lesions. Lesion ADC / normal parenchyma ADC ratios are more important than lesion ADC values in assessment of pancreatic lesions.

  1. Diffusion-weighted magnetic resonance imaging with apparent diffusion coefficient (ADC) determination in normal and pathological fetal kidneys.

    Science.gov (United States)

    Chaumoitre, K; Colavolpe, N; Shojai, R; Sarran, A; D' Ercole, C; Panuel, M

    2007-01-01

    To assess the use of diffusion-weighted magnetic resonance imaging (DW-MRI) in the evaluation of the fetal kidney and to estimate age-dependent changes in the apparent diffusion coefficient (ADC) of normal and pathological fetal kidneys. DW-MRI was performed on a 1.5-T machine at 23-38 gestational weeks in 51 pregnant women in whom the fetal kidneys were normal and in 10 whose fetuses had renal pathology (three with suspected nephropathy, three with renal tract dilatation, one with unilateral renal venous thrombosis, and three with twin-twin transfusion syndrome (TTTS)). The ADC was measured in an approximately 1-cm2 region of interest within the renal parenchyma. ADC values in normal renal parenchyma ranged from 1.1 to 1.8 10(-3) mm2 s-1. There was no significant age-dependent change in the ADC of normal kidneys. In cases of nephropathy, the ADC value was not always pathological but an ADC map could show abnormal findings. In cases of dilatation, the ADC value was difficult to determine when the dilatation was huge. In cases of TTTS, the ADC of the donor twin was higher than that of the recipient twin and the difference seemed to be related to the severity of the syndrome. Evaluation of the ADC for fetal kidneys is feasible. Fetal measurement of the ADC value and ADC maps may be useful tools with which to explore the fetal kidney when used in conjunction with current methods. DW-MR images, ADC value and ADC map seem to be useful in cases of suspected nephropathy (hyperechoic kidneys), dilated kidney and vascular pathology (renal venous thrombosis, TTTS). Copyright (c) 2006 ISUOG.

  2. Diffusion-weighted magnetic resonance imaging of the normal endometrium: temporal and spatial variations of the apparent diffusion coefficient

    International Nuclear Information System (INIS)

    Fornasa, Francesca; Montemezzi, Stefania

    2012-01-01

    Background: Diffusion-weighted magnetic resonance imaging (DWI) is increasingly used in the diagnosis of endometrial disease. No complete knowledge, however, exists yet of the influence of physiology on the endometrial apparent diffusion coefficient (ADC) values on which DWI is based. Purpose: To establish whether the ADC values measured with DWI in the endometrium of healthy reproductive-aged women significantly vary from the early proliferative to the periovulatory phase of the menstrual cycle and between the fundus and the isthmus of the uterus. Material and Methods: In 17 women the endometrial ADC values measured on the fifth menstrual day, both at the fundus and at the isthmus of the uterus, were compared to the values obtained on the 14th day before the subsequent cycle. In 81 women (menstrual day: fifth through 21st) the endometrial ADC values measured at the fundus were compared to the values obtained at the isthmus of the uterus. All examinations were performed with a 1.5 T magnet (b values: 0 and 800 mm/s 2 ). The results were analyzed by means of Student's t-test per paired data. Results: The endometrial ADC values measured on the fifth day of the menstrual cycle were lower than those obtained in the periovulatory phase both at the fundus (mean 0.923 vs. 1.256 x 10 - 3 mm 2 /s) and at the isthmus (mean 1.297 vs. 1.529 x 10 - 3 mm 2 /s) of the uterus. The endometrial ADC values measured at the fundus of the uterus were lower than those obtained at the isthmus (mean 1.132 vs. 1.420 x 10 - 3 mm 2 /s) through the menstrual cycle. All these differences were highly significant (P < 0.001) at statistical analysis. Conclusion: Physiological variations occurring in endometrial ADC values of healthy women should be considered by the radiologists when interpreting DWI examinations in patients with endometrial disease

  3. Comparison of magnetic resonance elastography and diffusion-weighted imaging for differentiating benign and malignant liver lesions

    Energy Technology Data Exchange (ETDEWEB)

    Hennedige, Tiffany P.; Hallinan, James Thomas Patrick Decourcy; Teo, Lynette Li San [National University Hospital, National University Health System, Department of Diagnostic Imaging, Singapore (Singapore); Leung, Fiona P. [National University Hospital, National University Health System, Department of Diagnostic Imaging, Singapore (Singapore); South West Radiology, Liverpool, NSW (Australia); Iyer, Sridhar; Chang, Stephen; Madhavan, Krishna Kumar [National University Health System, Department of Surgery, Singapore (Singapore); Wang, Gang [National University Hospital, National University Health System, Department of Diagnostic Imaging, Singapore (Singapore); University of Calgary, Alberta (Canada); Wee, Aileen [National University Hospital, National University Health System, Department of Pathology, Singapore (Singapore); Venkatesh, Sudhakar K. [Mayo Clinic, Department of Radiology, Rochester, MN (United States)

    2016-02-15

    Comparison of magnetic resonance elastography (MRE) and diffusion-weighted imaging (DWI) for differentiating malignant and benign focal liver lesions (FLLs). Seventy-nine subjects with 124 FLLs (44 benign and 80 malignant) underwent both MRE and DWI. MRE was performed with a modified gradient-echo sequence and DWI with a free breathing technique (b = 0.500). Apparent diffusion coefficient (ADC) maps and stiffness maps were generated. FLL mean stiffness and ADC values were obtained by placing regions of interest over the FLLs on stiffness and ADC maps. The accuracy of MRE and DWI for differentiation of benign and malignant FLL was compared using receiver operating curve (ROC) analysis. There was a significant negative correlation between stiffness and ADC (r = -0.54, p < 0.0001) of FLLs. Malignant FLLs had significantly higher mean stiffness (7.9kPa vs. 3.1kPa, p < 0.001) and lower mean ADC (129 vs. 200 x 10{sup -3}mm{sup 2}/s, p < 0.001) than benign FLLs. The sensitivity/specificity/positive predictive value/negative predictive value for differentiating malignant from benign FLLs with MRE (cut-off, >4.54kPa) and DWI (cut-off, <151 x 10{sup -3}mm{sup 2}/s) were 96.3/95.5/97.5/93.3 % (p < 0.001) and 85/81.8/88.3/75 % (p < 0.001), respectively. ROC analysis showed significantly higher accuracy for MRE than DWI (0.986 vs. 0.82, p = 0.0016). MRE is significantly more accurate than DWI for differentiating benign and malignant FLLs. (orig.)

  4. Can Diffusion-weighted Magnetic Resonance Imaging Predict Survival in Patients with Cervical Cancer? A Meta-Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu-Ting, E-mail: wangyuting_330@163.com; Li, Ying-Chun, E-mail: anicespringspring@163.com; Yin, Long-Lin, E-mail: yinlonglin@163.com; Pu, Hong, E-mail: ph196797@163.com

    2016-12-15

    Highlights: • DWI may serve as a prognostic factor in patients with cervical cancer. • Unfavorable DWI results (mostly low ADC) were associated with higher risks of tumor recurrence. • A quantified ADC was shown to be a suitable candidate indicator. - Abstract: Objective: Although diffusion-weighted magnetic resonance imaging (DWI) has been widely used in the diagnosis of cervical cancer, whether it can predict disease recurrence or survival remains inconclusive. This study aimed to systematically evaluate whether DWI can serve as a reliable prognostic predictor in patients with cervical cancer. Methods: PubMed, the MEDLINE database and the Cochrane Library were searched for DWI studies with >12 months of prognostic data in patients with cervical cancer. Endpoints included tumor recurrence and death. Methodological quality was assessed using the Quality in Prognostic Studies (QUIPS) tool. Combined estimates of hazard ratios (HRs) were derived. Results: Nine studies involving a total of 796 patients (mean/median age from 45.0 years to 62.9 years) met the inclusion criteria. Methodological quality was relatively high. Eight of the nine studies employed apparent diffusion coefficient (ADC) as an indicator of DWI results. Using disease-free survival (DFS) as an outcome measure, nine studies yielded a combined HR of 1.55 (95% confidence interval (CI): 1.23–1.95), and seven studies that employed pretreatment DWI yielded a combined HR of 1.50 (95% CI: 1.03–2.19), which indicated that unfavorable DWI results were associated with an approximately 1.50–1.55-fold higher risk of tumor recurrence. The two studies investigating the impact of DWI results on overall survival (OS) reported HRs of 7.20 and 2.17, respectively. Conclusion: DWI may serve as a predictor of tumor recurrence in patients with cervical cancer as showed by meta-analysis, and the quantified ADC as a suitable candidate indicator.

  5. Diffusion weighted MR imaging in the diagnosis of multiple sclerosis

    International Nuclear Information System (INIS)

    Hagen, T.; Schweigerer-Schroeter, G.; Wellnitz, J.; Wuerstle, T.

    2000-01-01

    Magnetic resonance (MR) imaging is one of the best methods in diagnosis of multiple sclerosis, particularly in disclosure of active demyelinating lesions. Aim of this study was to compare diffusion weighted imaging and contrast enhancement in the detection of active lesions. A MR study with a contrast enhanced T1-weighted pulse sequence with magnetization transfer presaturation and a diffusion weighted echoplanar pulse sequence (b=1000 s/mm 2 ) was performed in 17 patients (11 women, 6 men) with multiple sclerosis. 29 of 239 lesions showed an increased signal intensity in diffusion weighted imaging, 24 lesions a contrast enhancement, but only 16 lesions were visible in both pulse sequences. In patients with short clinical symptomatology significant more lesions could be detected with diffusion-weighted pulse sequence in comparison to patients with long standing symptomatology showing more lesions with contrast enhancement. Hence it is likely, that both pulse sequences detect different histopathologic changes. The early detection of demyelinating lesions in diffusion weighted imaging is attributed to the extracellular edema, however the contrast enhancement is caused by a blood brain barrier abnormality. It can be expected that diffusion weighted imaging will have a high impact on imaging of multiple sclerosis not only in therapeutic trials, but also in clinical routine. (orig.) [de

  6. Clinical utility of high b-value diffusion-weighted magnetic resonance imaging in post-resuscitative encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Kano, Hitoshi; Danjou, Wataru; Yamazaki, Kei [Sapporo City General Hospital (Japan)] (and others)

    2002-03-01

    It is very important to estimate brain functional capacity immediately after successful cardiopulmonary resuscitation (CPR) to determine subsequent treatment strategy and to elucidate the pathophysiology of patients with post-resuscitative encephalopathy. However, computed tomography scanning, electric encephalography and conventional magnetic resonance imaging do not contribute significantly to the assessment of brain functions immediately after CPR. Recently, diffusion-weighted magnetic resonance imaging (DW-MRI) has been applied to the patients with post-resuscitative encephalopathy. However, no papers have described serial clinical and repeated DW-MRI studies of patients during the acute phase of post-resuscitative encephalopathy. Moreover, in some cases, high signal intensity in the cortex after CPR is indistinguishable from normal cortex. Thus, we tried to apply high b-value DW-MRI to estimate the brain function of patients with post-resuscitative encephalopathy. This study was performed on 11 patients with post-resuscitative encephalopathy and 5 healthy volunteers as controls. DW-MRI was performed using GYROSCAN 1.5 Tesla MR imager (Philips) with single-shot echo-planner imaging sequences performed 3 times, first within 24 hours after CPR, second between day 3 to 6, and third more than 7 days after CPR. And we tested the usefulness of DW-MRI at 800, 1000, 1500, 2000 and 3000 in b value. Five patients survived, one fully recovered and four remained in a vegetative state. The other six died with clinical brain death. The first DW-MRI revealed in high signal intensity in the frontal and the parietal lobes in all patients who eventually progressed to a vegetative state or brain death. This result was much more wide-spread in the latter patients, while it was never seen in the patients who recovered fully. The high signal intensity areas increased in follow-up DW-MRI studies. The signal intensity remained high in some parts, while it decreased in other parts with

  7. Clinical utility of high b-value diffusion-weighted magnetic resonance imaging in post-resuscitative encephalopathy

    International Nuclear Information System (INIS)

    Kano, Hitoshi; Danjou, Wataru; Yamazaki, Kei

    2002-01-01

    It is very important to estimate brain functional capacity immediately after successful cardiopulmonary resuscitation (CPR) to determine subsequent treatment strategy and to elucidate the pathophysiology of patients with post-resuscitative encephalopathy. However, computed tomography scanning, electric encephalography and conventional magnetic resonance imaging do not contribute significantly to the assessment of brain functions immediately after CPR. Recently, diffusion-weighted magnetic resonance imaging (DW-MRI) has been applied to the patients with post-resuscitative encephalopathy. However, no papers have described serial clinical and repeated DW-MRI studies of patients during the acute phase of post-resuscitative encephalopathy. Moreover, in some cases, high signal intensity in the cortex after CPR is indistinguishable from normal cortex. Thus, we tried to apply high b-value DW-MRI to estimate the brain function of patients with post-resuscitative encephalopathy. This study was performed on 11 patients with post-resuscitative encephalopathy and 5 healthy volunteers as controls. DW-MRI was performed using GYROSCAN 1.5 Tesla MR imager (Philips) with single-shot echo-planner imaging sequences performed 3 times, first within 24 hours after CPR, second between day 3 to 6, and third more than 7 days after CPR. And we tested the usefulness of DW-MRI at 800, 1000, 1500, 2000 and 3000 in b value. Five patients survived, one fully recovered and four remained in a vegetative state. The other six died with clinical brain death. The first DW-MRI revealed in high signal intensity in the frontal and the parietal lobes in all patients who eventually progressed to a vegetative state or brain death. This result was much more wide-spread in the latter patients, while it was never seen in the patients who recovered fully. The high signal intensity areas increased in follow-up DW-MRI studies. The signal intensity remained high in some parts, while it decreased in other parts with

  8. Role of Diffusion-Weighted Magnetic Resonance (MR) Imaging in Differentiation Between Graves' Disease and Painless Thyroiditis.

    Science.gov (United States)

    Abdel Razek, Ahmed Abdel Khalek; Abd Allah, Sieza Samir; El-Said, Amr Abd El-Hamid

    2017-01-01

    To assess the role of diffusion-weighted MR imaging in differentiation between Graves' disease and painless thyroiditis. A prospective study was conducted among 37 consecutive patients with untreated thyrotoxicosis (25 female and 12 male; mean age of 44 years) and 15 ageand sex-matched controls. Diffusion-weighted MR imaging of the thyroid gland was performed in patients and controls. The apparent diffusion coefficient (ADC) value of the thyroid gland was calculated and correlated with Tc-99m uptake and thyroid function tests of the patients. There was a significant difference in the ADC value of the thyroid gland between patients and the control group ( P =0.001). The mean ADC value of the thyroid gland in Graves' disease was 2.03±0.28×10 -3 mm 2 /sec, and in patients with painless thyroiditis 1.46±0.22×10 -3 mm 2 /sec, respectively. There was a significant difference in the ADC values between Graves' disease and painless thyroiditis ( P =0.001). When the ADC value of 1.45×10 -3 mm 2 /sec was used as a threshold value for differentiating Graves' disease from painless thyroiditis, the best result was obtained with area under the curve of 0.934, accuracy of 83.8%, sensitivity of 95.8%, and specificity of 61.5%. The mean ADC value of the thyroid gland in patients positively correlated with serum TRAb and Tc-99m uptake ( r =0.57, P =0.001 and r =0.74, P =0.001, respectively). We concluded that ADC values of the thyroid gland can be used to differentiate Graves' disease from painless thyroiditis in patients with untreated thyrotoxicosis.

  9. Role of Diffusion-Weighted Magnetic Resonance (MR) Imaging in Differentiation Between Graves’ Disease and Painless Thyroiditis

    Science.gov (United States)

    Abdel Razek, Ahmed Abdel Khalek; El-Said, Amr Abd El-hamid

    2017-01-01

    Summary Background To assess the role of diffusion-weighted MR imaging in differentiation between Graves’ disease and painless thyroiditis. Material/Methods A prospective study was conducted among 37 consecutive patients with untreated thyrotoxicosis (25 female and 12 male; mean age of 44 years) and 15 ageand sex-matched controls. Diffusion-weighted MR imaging of the thyroid gland was performed in patients and controls. The apparent diffusion coefficient (ADC) value of the thyroid gland was calculated and correlated with Tc-99m uptake and thyroid function tests of the patients. Results There was a significant difference in the ADC value of the thyroid gland between patients and the control group (P=0.001). The mean ADC value of the thyroid gland in Graves’ disease was 2.03±0.28×10–3 mm2/sec, and in patients with painless thyroiditis 1.46±0.22×10–3 mm2/sec, respectively. There was a significant difference in the ADC values between Graves’ disease and painless thyroiditis (P=0.001). When the ADC value of 1.45×10–3 mm2/sec was used as a threshold value for differentiating Graves’ disease from painless thyroiditis, the best result was obtained with area under the curve of 0.934, accuracy of 83.8%, sensitivity of 95.8%, and specificity of 61.5%. The mean ADC value of the thyroid gland in patients positively correlated with serum TRAb and Tc-99m uptake (r=0.57, P=0.001 and r=0.74, P=0.001, respectively). Conclusions We concluded that ADC values of the thyroid gland can be used to differentiate Graves’ disease from painless thyroiditis in patients with untreated thyrotoxicosis. PMID:29662585

  10. Myometrial invasion and overall staging of endometrial carcinoma: assessment using fusion of T2-weighted magnetic resonance imaging and diffusion-weighted magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Guo Y

    2017-12-01

    Full Text Available Yu Guo,1,2 Ping Wang,2 Penghui Wang,2 Wei Gao,1 Fenge Li,3 Xueling Yang,1 Hongyan Ni,2 Wen Shen,2 Zhi Guo1 1Department of Interventional Therapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin’s Clinical Research Center for Cancer, Tianjin, 2Department of Radiology, Tianjin First Center Hospital, The First Central Clinical College of Tianjin Medical University, Tianjin, 3Department of Gynecology, Tianjin First Center Hospital, Tianjin, People’s Republic of China Background: The age of onset of endometrial carcinoma has been decreasing in recent years. In endometrial carcinoma, it is important to accurately assess invasion depth and preoperative staging. Fusion of T2-weighted magnetic resonance imaging (T2WI and diffusion-weighted magnetic resonance imaging (DWI may contribute to the improvement of anatomical localization of lesions.Materials and methods: In our study, a total of 58 endometrial carcinoma cases were included. Based on the revised 2009 International Federation of Gynecology and Obstetrics staging system, a fusion of T2WI and DWI was utilized for the evaluation of invasion depth and determination of the overall stage. Postoperative pathologic assessment was considered as the reference standard. The consistency of T2WI image staging and pathologic staging, and the consistency of fused T2WI and DWI and pathologic staging were all analyzed using Kappa statistics.Results: Compared with the T2WI group, a significantly higher diagnostic accuracy was observed for myometrial invasion with fusion of T2WI and DWI (77.6% for T2WI; 94.8% for T2WI-DWI. For the identification of deep invasion, we calculated values for diagnostic sensitivity (69.2% for T2WI; 92.3% for T2WI-DWI, specificity (80% for T2WI; 95.6% for T2WI-DWI, positive predictive value (50% for T2WI; 85.7% for T2WI-DWI, and negative predictive value (90% for

  11. Diffusion weighted imaging (DWI) in the abdomen

    International Nuclear Information System (INIS)

    Collaku, A.

    2013-01-01

    Full text: Introduction: The use of diffusion weighted images when performing abdomen MRI has been increased during the last years; achieving high quality images for a short period of time remains still a challenge. Learning points: We present a literature review together with our experience in optimizing the DW imaging in the abdomen, focused on creating high density ADC maps and handling the uncooperative patients. Discussion: The factors that influence the image quality are discussed as well. Conclusion: The factors that influence the image quality are discussed as well

  12. Noninvasive monitoring of radiation-induced treatment response using proton magnetic resonance spectroscopy and diffusion-weighted magnetic resonance imaging in a colorectal tumor model

    International Nuclear Information System (INIS)

    Seierstad, Therese; Roe, Kathrine; Olsen, Dag Rune

    2007-01-01

    Background and purpose: To examine whether in vivo proton magnetic resonance spectroscopy ( 1 H MRS) and diffusion-weighted magnetic resonance imaging (DW-MRI) can monitor radiation-induced changes in HT29 xenografts in mice. Materials and methods: HT29 xenografts in mice received a dose of 15 Gy. In vivo 1 H MRS and DW-MRI were acquired pretreatment and 1, 3, 6 and 10 days post-irradiation. After imaging, tumors were excised for histological analysis. The amounts of necrosis, fibrosis and viable cells in the cross sections were scored and compared to changes in apparent diffusion coefficient (ADC) and choline/water ratio. Results: Radiation-induced necrosis in the xenografts was observed as increased tumor ADC. In-growth of fibrosis three days post-irradiation restricting water mobility was accompanied by decreased tumor ADC. Choline/water ratio correlated with metabolic activity and tumor growth. Conclusions: ADC and choline/water ratio assessed by in vivo DW-MRI and 1 H MRS depicts radiation-induced changes in HT29 xenografts following irradiation

  13. Inter-Observer Agreement on Diffusion-Weighted Magnetic Resonance Imaging Interpretation for Diagnosis of Acute Ischemic Stroke Among Emergency Physicians

    Directory of Open Access Journals (Sweden)

    Deniz ORAY

    2015-06-01

    Full Text Available SUMMARY: Objectives: Diffusion-weighted magnetic resonance imaging (DW-MRI is a highly sensitive tool for the detection of early ischemic stroke and is excellent at detecting small and early infarcts. Nevertheless, conflict may arise and judgments may differ among different interpreters. Inter-observer variability shows the systematic difference among different observers and is expressed as the kappa (Κ coefficient. In this study, we aimed to determinate the inter-observer variability among emergency physicians in the use of DW-MRI for the diagnosis of acute ischemic stroke. Methods: Cranial DW-MRI images of 50 patients were interpreted in this retrospective observational cross-sectional study. Patients who were submitted to DW-MRI imaging for a suspected acute ischemic stroke were included in the study, unless the scans were ordered by any of the reviewers or they were absent in the system. The scans were blindly and randomly interpreted by four emergency physicians. Inter-observer agreement between reviewers was evaluated using Fleiss’ Κ statistics. Results: The mean kappa value for high signal on diffusion-weighted images (DWI and for reduction on apparent diffusion coefficient (ADC were substantial (k=0.67 and moderate (k=0.60 respectively. The correlation for detection of the presence of ischemia and location was substantial (k: 0.67. There were 18 false-positive and 4 false-negative evaluations of DWI, 15 false positive and 8 false-negative evaluations of ADC. Conclusions: Our data suggest that DW-MRI is reliable in screening for ischemic stroke when interpreted by emergency physicians in the emergency department. The levels of stroke identification and variability show that emergency physicians may have an acceptable level of agreement. Key words: Emergency department, diffusion weighted magnetic resonance imaging, inter-observer agreement, ischemic stroke

  14. Incorporation of diffusion-weighted magnetic resonance imaging data into a simple mathematical model of tumor growth

    International Nuclear Information System (INIS)

    Atuegwu, N C; Colvin, D C; Loveless, M E; Gore, J C; Yankeelov, T E; Xu, L

    2012-01-01

    We build on previous work to show how serial diffusion-weighted MRI (DW-MRI) data can be used to estimate proliferation rates in a rat model of brain cancer. Thirteen rats were inoculated intracranially with 9L tumor cells; eight rats were treated with the chemotherapeutic drug 1,3-bis(2-chloroethyl)-1-nitrosourea and five rats were untreated controls. All animals underwent DW-MRI immediately before, one day and three days after treatment. Values of the apparent diffusion coefficient (ADC) were calculated from the DW-MRI data and then used to estimate the number of cells in each voxel and also for whole tumor regions of interest. The data from the first two imaging time points were then used to estimate the proliferation rate of each tumor. The proliferation rates were used to predict the number of tumor cells at day three, and this was correlated with the corresponding experimental data. The voxel-by-voxel analysis yielded Pearson's correlation coefficients ranging from −0.06 to 0.65, whereas the region of interest analysis provided Pearson's and concordance correlation coefficients of 0.88 and 0.80, respectively. Additionally, the ratio of positive to negative proliferation values was used to separate the treated and control animals (p <0.05) at an earlier point than the mean ADC values. These results further illustrate how quantitative measurements of tumor state obtained non-invasively by imaging can be incorporated into mathematical models that predict tumor growth. (paper)

  15. Everyman's prostate phantom: kiwi-fruit substitute for human prostates at magnetic resonance imaging, diffusion-weighted imaging and magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Lisse, Ullrich G.; Murer, Sophie; Kuhn, Marissa [University of Munich (' ' Ludwig-Maximilians-Universitaet' ' , LMU), Department of Radiology, Faculty of Medicine, Muenchen (Germany); Mueller-Lisse, Ulrike L. [University of Munich (' ' Ludwig-Maximilians-Universitaet' ' , LMU), Department of Urology, Faculty of Medicine, Muenchen (Germany); Interdisciplinary Oncology Centre Munich (IOZ), Department of Urology, Munich (Germany); Scheidler, Juergen [University of Munich (' ' Ludwig-Maximilians-Universitaet' ' , LMU), Department of Radiology, Faculty of Medicine, Muenchen (Germany); Radiology Centre Munich (RZM), Muenchen (Germany); Scherr, Michael [University of Munich (' ' Ludwig-Maximilians-Universitaet' ' , LMU), Department of Radiology, Faculty of Medicine, Muenchen (Germany); BG Unfallklinik Murnau, Department of Radiology, Murnau am Staffelsee (Germany)

    2017-08-15

    To apply an easy-to-assemble phantom substitute for human prostates in T2-weighted magnetic resonance imaging (T2WI), diffusion-weighted imaging (DWI) and 3D magnetic resonance spectroscopy (MRS). Kiwi fruit were fixed with gel hot and cold compress packs on two plastic nursery pots, separated by a plastic plate, and submerged in tap water inside a 1-L open-spout plastic watering can for T2WI (TR/TE 7500/101 ms), DWI (5500/61 ms, ADC b50-800 s/mm{sup 2} map) and MRS (940/145 ms) at 3.0 T, with phased array surface coils. One green kiwi fruit was additionally examined with an endorectal coil. Retrospective comparison with benign peripheral zone (PZ) and transitional zone (TZ) of prostate (n = 5), Gleason 6-7a prostate cancer (n = 8) and Gleason 7b-9 prostate cancer (n = 7) validated the phantom. Mean contrast between central placenta (CP) and outer pericarp (OP, 0.346-0.349) or peripheral placenta (PP, 0.364-0.393) of kiwi fruit was similar to Gleason 7b-9 prostate cancer and PZ (0.308) in T2WI. ADC values of OP and PP (1.27 ± 0.07-1.37 ± 0.08 mm{sup 2}/s x 10{sup -3}) resembled PZ and TZ (1.39 ± 0.17-1.60 ± 0.24 mm{sup 2}/s x 10{sup -3}), while CP (0.91 ± 0.14-0.99 ± 0.10 mm{sup 2}/s x 10{sup -3}) resembled Gleason 7b-9 prostate cancer (1.00 ± 0.25 mm{sup 2}/s x 10{sup -3}). MR spectra showed peaks of citrate and myo-inositol in kiwi fruit, and citrate and ''choline+creatine'' in prostates. The phantom worked with an endorectal coil, too. The kiwi fruit phantom reproducibly showed zones similar to PZ, TZ and cancer in human prostates in T2WI and DWI and two metabolite peaks in MRS and appears suitable to compare different MR protocols, coil systems and scanners. (orig.)

  16. Diffusion weighted imaging in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Cher Heng [The University of Texas, M D Anderson Cancer Center, Department of Diagnostic Radiology, Division of Diagnostic Imaging, Houston, TX (United States); Tan Tock Seng Hospital, Department of Diagnostic Radiology, Singapore (Singapore); Wang, Jihong [The University of Texas, M D Anderson Cancer Center, Department of Imaging Physics, Division of Diagnostic Imaging, Houston, TX (United States); Kundra, Vikas [The University of Texas, M D Anderson Cancer Center, Department of Diagnostic Radiology, Division of Diagnostic Imaging, Houston, TX (United States); The University of Texas, M D Anderson Cancer Center, Department of Experimental Diagnostic Imaging, Division of Diagnostic Imaging, Houston, TX (United States)

    2011-03-15

    Diffusion-weighted imaging has generated substantial interest in the hope that it can be developed into a robust technique to improve the accuracy of MRI for the evaluation of prostate cancer. This technique has the advantages of short acquisition times, no need for intravenous administration of contrast medium, and the ability to study diffusion of water molecules that indirectly reflects tissue cellularity. In this article, we review the existing literature on the utility of DWI in tumour detection, localisation, treatment response, limitations of the technique, how it compares with other imaging techniques, technical considerations and future directions. (orig.)

  17. Diffusion-weighted MR imaging for detection of extrahepatic cholangiocarcinoma

    International Nuclear Information System (INIS)

    Cui, Xing-Yu; Chen, Hong-Wei; Cai, Song; Bao, Jian; Tang, Qun-Feng; Wu, Li-Yuan; Fang, Xiang-Ming

    2012-01-01

    Objectives: To measure the sensitivity of diffusion-weighted imaging (DWI) and determine the most appropriate b value for DWI; to explore the correlation between the apparent diffusion coefficient (ADC) value and the degree of extrahepatic cholangiocarcinoma differentiation. Methods: Preoperative diffusion-weighted imaging and magnetic resonance examinations were performed for 31 patients with extrahepatic cholangiocarcinoma. Tumor ADC values were measured, and the signal-to-noise ratio, contrast-to-noise ratio, and signal-intensity ratio between the diffusion-weighted images with various b values as well as the T2-weighted images were calculated. Pathologically confirmed patients were pathologically graded to compare the ADC value with different b values of tumor at different degrees of differentiation, and the results were statistically analyzed by using the Friedman test. Results: A total of 29 cases of extrahepatic cholangiocarcinoma were detected by DWI. As the b value increased, tumor signal-to-noise ratio and contrast-to-noise ratio between the tumor and normal liver gradually decreased, but the tumor signal-intensity ratio gradually increased. When b = 800 s/mm 2 , contrast-to-noise ratio between tumor and normal liver, tumor signal-intensity ratio, and tumor signal-to-noise ratio of diffusion-weighted images were all higher than those of T2-weighted images; the differences were statistically significant (P 2 was the best in DWI of extrahepatic cholangiocarcinoma; the lesion ADC value declined as the degree of cancerous tissue differentiation decreased.

  18. The role of magnetic resonance diffusion-weighted imaging and three-dimensional arterial spin labelling perfusion imaging in the differentiation of parasellar meningioma and cavernous haemangioma.

    Science.gov (United States)

    Xiao, Hua-Feng; Lou, Xin; Liu, Meng-Yu; Wang, Yu-Lin; Wang, Yan; Chen, Zhi-Ye; Shi, Kai-Ning; Ma, Lin

    2014-08-01

    To evaluate the diagnostic value of magnetic resonance diffusion-weighted imaging (DWI) and three-dimensional arterial spin labelling perfusion imaging (3D-ASL) in distinguishing cavernous haemangioma from parasellar meningioma, using histological data as a reference standard. Patients with parasellar meningioma or parasellar cavernous haemangioma underwent conventional T1- and T2-weighted magnetic resonance imaging (MRI) followed by DWI and 3D-ASL using a 3.0 Tesla MRI. The minimum apparent diffusion coefficient (minADC) from DWI and the maximal normalized cerebral blood flow (nCBF) from 3D-ASL were measured in each tumour. Diagnosis was confirmed by histology. MinADC was significantly lower and nCBF significantly higher in meningioma (n = 19) than cavernous haemangioma (n = 15). There was a significant negative correlation between minADC and nCBF (r = -0.605). DWI and 3D-ASL are useful in differentiating cavernous haemangiomas from parasellar meningiomas, particularly in situations when the appearance on conventional MRI sequences is otherwise ambiguous. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. Non-contrast magnetic resonance imaging for bladder cancer: fused high b value diffusion-weighted imaging and T2-weighted imaging helps evaluate depth of invasion

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Minsu; Oh, Young Taik; Jung, Dae Chul; Park, Sung Yoon [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Shin, Su-Jin [Yonsei University College of Medicine, Department of Pathology, Seoul (Korea, Republic of); Hanyang University College of Medicine, Department of Pathology, Seoul (Korea, Republic of); Cho, Nam Hoon [Yonsei University College of Medicine, Department of Pathology, Seoul (Korea, Republic of); Choi, Young Deuk [Yonsei University College of Medicine, Department of Urology, Seoul (Korea, Republic of)

    2017-09-15

    To investigate the utility of fused high b value diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) for evaluating depth of invasion in bladder cancer. We included 62 patients with magnetic resonance imaging (MRI) and surgically confirmed urothelial carcinoma in the urinary bladder. An experienced genitourinary radiologist analysed the depth of invasion (T stage <2 or ≥2) using T2WI, DWI, T2WI plus DWI, and fused DWI and T2WI (fusion MRI). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were investigated. Area under the curve (AUC) was analysed to identify T stage ≥2. The rate of patients with surgically confirmed T stage ≥2 was 41.9% (26/62). Sensitivity, specificity, PPV, NPV and accuracy were 50.0%, 55.6%, 44.8%, 60.6% and 53.2%, respectively, with T2WI; 57.7%, 77.8%, 65.2%, 71.8% and 69.4%, respectively, with DWI; 65.4%, 80.6%, 70.8%, 76.3% and 74.2%, respectively, with T2WI plus DWI and 80.8%, 77.8%, 72.4%, 84.9% and 79.0%, respectively, with fusion MRI. AUC was 0.528 with T2WI, 0.677 with DWI, 0.730 with T2WI plus DWI and 0.793 with fusion MRI for T stage ≥2. Fused high b value DWI and T2WI may be a promising non-contrast MRI technique for assessing depth of invasion in bladder cancer. (orig.)

  20. Non-contrast magnetic resonance imaging for bladder cancer: fused high b value diffusion-weighted imaging and T2-weighted imaging helps evaluate depth of invasion

    International Nuclear Information System (INIS)

    Lee, Minsu; Oh, Young Taik; Jung, Dae Chul; Park, Sung Yoon; Shin, Su-Jin; Cho, Nam Hoon; Choi, Young Deuk

    2017-01-01

    To investigate the utility of fused high b value diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) for evaluating depth of invasion in bladder cancer. We included 62 patients with magnetic resonance imaging (MRI) and surgically confirmed urothelial carcinoma in the urinary bladder. An experienced genitourinary radiologist analysed the depth of invasion (T stage <2 or ≥2) using T2WI, DWI, T2WI plus DWI, and fused DWI and T2WI (fusion MRI). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were investigated. Area under the curve (AUC) was analysed to identify T stage ≥2. The rate of patients with surgically confirmed T stage ≥2 was 41.9% (26/62). Sensitivity, specificity, PPV, NPV and accuracy were 50.0%, 55.6%, 44.8%, 60.6% and 53.2%, respectively, with T2WI; 57.7%, 77.8%, 65.2%, 71.8% and 69.4%, respectively, with DWI; 65.4%, 80.6%, 70.8%, 76.3% and 74.2%, respectively, with T2WI plus DWI and 80.8%, 77.8%, 72.4%, 84.9% and 79.0%, respectively, with fusion MRI. AUC was 0.528 with T2WI, 0.677 with DWI, 0.730 with T2WI plus DWI and 0.793 with fusion MRI for T stage ≥2. Fused high b value DWI and T2WI may be a promising non-contrast MRI technique for assessing depth of invasion in bladder cancer. (orig.)

  1. Diffusion-weighted imaging and magnetic resonance spectroscopy of sporadic Creutzfeldt-Jakob disease: correlation with clinical course

    International Nuclear Information System (INIS)

    Kim, Jae Hyoung; Choi, Byung Se; Jung, Cheolkyu; Chang, YoungHee; Kim, SangYun

    2011-01-01

    Sporadic Creutzfeldt-Jakob disease (sCJD) is a fatal disease with variable clinical courses. The presence or absence of basal ganglia (BG) involvement has been reported to be associated with clinical course. We investigated the association of clinical course of sCJD with diffusion-weighted imaging (DWI) and MR spectroscopy (MRS) as well as BG involvement at early stage. DWI and single voxel proton MRS were performed in 14 patients with sCJD during the initial diagnostic workup. Apparent diffusion coefficient (ADC) and metabolites were measured in medial occipitoparietal cortices where large hyperintense DWI lesions were found in all patients. The presence or absence of BG involvement, ADC, N-acetylaspartate (NAA)/creatine (Cr) ratios, and choline (Cho)/Cr ratios were correlated with disease duration (i.e., the time from the symptom onset to death). The disease duration ranged from 2 to 31 months (median, 16). Hyperintense DWI lesions were observed bilaterally in both cortices and basal ganglia in eight patients and in cortices alone in six patients. Patients with BG involvement had shorter disease duration (median, 6.8 versus 20.5; p = 0.039) than those without and lower NAA/Cr ratios (median, 1.41 versus 2.03; p = 0.001). ADC and Cho/Cr ratios were not significantly different between the patients with BG involvement and those without. By multiple regression analysis, NAA/Cr ratios had the greatest correlation with the disease duration (p = 0.029). The disease duration of sCJD was variable. NAA/Cr ratios of the affected brain at the early stage of sCJD can be used as a useful parameter in predicting the clinical course. (orig.)

  2. Diffusion-weighted imaging and magnetic resonance spectroscopy of sporadic Creutzfeldt-Jakob disease: correlation with clinical course

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Hyoung; Choi, Byung Se; Jung, Cheolkyu [Seoul National University Bundang Hospital, Department of Radiology, Seoul National University College of Medicine, Seongnam-si (Korea, Republic of); Chang, YoungHee; Kim, SangYun [Seoul National University Bundang Hospital, Department of Neurology, Seoul National University College of Medicine, Seongnam-si (Korea, Republic of)

    2011-12-15

    Sporadic Creutzfeldt-Jakob disease (sCJD) is a fatal disease with variable clinical courses. The presence or absence of basal ganglia (BG) involvement has been reported to be associated with clinical course. We investigated the association of clinical course of sCJD with diffusion-weighted imaging (DWI) and MR spectroscopy (MRS) as well as BG involvement at early stage. DWI and single voxel proton MRS were performed in 14 patients with sCJD during the initial diagnostic workup. Apparent diffusion coefficient (ADC) and metabolites were measured in medial occipitoparietal cortices where large hyperintense DWI lesions were found in all patients. The presence or absence of BG involvement, ADC, N-acetylaspartate (NAA)/creatine (Cr) ratios, and choline (Cho)/Cr ratios were correlated with disease duration (i.e., the time from the symptom onset to death). The disease duration ranged from 2 to 31 months (median, 16). Hyperintense DWI lesions were observed bilaterally in both cortices and basal ganglia in eight patients and in cortices alone in six patients. Patients with BG involvement had shorter disease duration (median, 6.8 versus 20.5; p = 0.039) than those without and lower NAA/Cr ratios (median, 1.41 versus 2.03; p = 0.001). ADC and Cho/Cr ratios were not significantly different between the patients with BG involvement and those without. By multiple regression analysis, NAA/Cr ratios had the greatest correlation with the disease duration (p = 0.029). The disease duration of sCJD was variable. NAA/Cr ratios of the affected brain at the early stage of sCJD can be used as a useful parameter in predicting the clinical course. (orig.)

  3. Interpolation of diffusion weighted imaging datasets

    DEFF Research Database (Denmark)

    Dyrby, Tim B; Lundell, Henrik; Burke, Mark W

    2014-01-01

    anatomical details and signal-to-noise-ratio for reliable fibre reconstruction. We assessed the potential benefits of interpolating DWI datasets to a higher image resolution before fibre reconstruction using a diffusion tensor model. Simulations of straight and curved crossing tracts smaller than or equal......Diffusion weighted imaging (DWI) is used to study white-matter fibre organisation, orientation and structural connectivity by means of fibre reconstruction algorithms and tractography. For clinical settings, limited scan time compromises the possibilities to achieve high image resolution for finer...... interpolation methods fail to disentangle fine anatomical details if PVE is too pronounced in the original data. As for validation we used ex-vivo DWI datasets acquired at various image resolutions as well as Nissl-stained sections. Increasing the image resolution by a factor of eight yielded finer geometrical...

  4. Audit of a policy of magnetic resonance imaging with diffusion-weighted imaging as first-line neuroimaging for in-patients with clinically suspected acute stroke

    International Nuclear Information System (INIS)

    Buckley, B.T.; Wainwright, A.; Meagher, T.; Briley, D.

    2003-01-01

    AIM: To audit the feasibility and use of diffusion-weighted (DW) magnetic resonance imaging (MRI) as initial neuroimaging for in-patients with clinically suspected acute stroke. MATERIALS AND METHODS: In April 2000, MRI with DW and T2-weighted sequence was locally instituted as initial neuroimaging for patients with clinically suspected acute stroke. This retrospective study reviewed imaging performed for in-patients with suspected acute stroke over a 9-month period. Data were collected on image type, result and need for repeat imaging. RESULTS: During the study period, 124 patients had neuroimaging for suspected cerebrovascular accident, and 119 were MRI safe. Eighty-eight (73.9%) patients underwent DW MRI as first-line investigation. Five patients were not MRI safe and 31 had computed tomography (CT) as first-line imaging due to lack of available MRI capacity. Repeat neuroimaging was performed in 16 (12.9%) patients. Study times were comparable for both types of neuroimaging: a mean of 13 min for MRI and 11 min for CT. CONCLUSION: The audit standard was achieved in 88 (73.9%) patients. The use of DW MRI as a first-line investigation for patients with a clinical diagnosis of acute stroke is achievable in a district general hospital setting

  5. Audit of a policy of magnetic resonance imaging with diffusion-weighted imaging as first-line neuroimaging for in-patients with clinically suspected acute stroke

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, B.T.; Wainwright, A.; Meagher, T.; Briley, D

    2003-03-01

    AIM: To audit the feasibility and use of diffusion-weighted (DW) magnetic resonance imaging (MRI) as initial neuroimaging for in-patients with clinically suspected acute stroke. MATERIALS AND METHODS: In April 2000, MRI with DW and T2-weighted sequence was locally instituted as initial neuroimaging for patients with clinically suspected acute stroke. This retrospective study reviewed imaging performed for in-patients with suspected acute stroke over a 9-month period. Data were collected on image type, result and need for repeat imaging. RESULTS: During the study period, 124 patients had neuroimaging for suspected cerebrovascular accident, and 119 were MRI safe. Eighty-eight (73.9%) patients underwent DW MRI as first-line investigation. Five patients were not MRI safe and 31 had computed tomography (CT) as first-line imaging due to lack of available MRI capacity. Repeat neuroimaging was performed in 16 (12.9%) patients. Study times were comparable for both types of neuroimaging: a mean of 13 min for MRI and 11 min for CT. CONCLUSION: The audit standard was achieved in 88 (73.9%) patients. The use of DW MRI as a first-line investigation for patients with a clinical diagnosis of acute stroke is achievable in a district general hospital setting.

  6. Cerebral ischemic lesions detected with diffusion-weighted magnetic resonance imaging after carotid artery stenting. Comparison of several anti-embolic protection devices

    International Nuclear Information System (INIS)

    Taha, M.M.; Maeda, Masayuki; Sakaida, Hiroshi

    2009-01-01

    Distal embolism is an important periprocedural technical complication with carotid angioplasty and carotid artery stenting (CAS). We evaluated the safety and efficacy of protection devices used during CAS by detecting new cerebral ischemic lesions using diffusion-weighted magnetic resonance imaging in 95 patients who underwent 98 CAS procedures: 34 using single PercuSurge GuardWire, 31 using double balloon protection, 15 using proximal flow reverse protection devices, 14 using Naviballoon, and 4 using filter anti-embolic devices. Diffusion-weighted imaging was performed preoperatively and postoperatively to evaluate the presence of any new embolic cerebral lesions. Postoperative diffusion-weighted imaging revealed 117 new ischemic lesions. Three patients had new ischemic stroke, two minor and one major, all ipsilateral to the treated carotid artery. The remaining patients had clinically silent ischemia. The incidence of new embolic lesions was lower using the proximal flow reverse protection device than with the double balloon protection (33% vs. 48.4%), but the volume of ipsilateral new ischemic lesions per patient was 136.6 mm 3 vs. 86.9 mm 3 , respectively. Neuroprotection with Naviballoon yielded ipsilateral lesions of large volume (86.6 mm 3 ) and higher number (5.7 lesions per patient) than using the filter anti-embolic device (34.8 mm 3 and 1 lesion per patient). New cerebral ischemic lesions after neuroprotected CAS are usually silent. The lower incidence of distal ischemia using proximal flow reverse and double balloon protection devices is limited by the larger volume and higher number of ischemic lesions. (author)

  7. Cerebral ischemic lesions detected with diffusion-weighted magnetic resonance imaging after carotid artery stenting: Comparison of several anti-embolic protection devices.

    Science.gov (United States)

    Taha, Mahmoud M; Maeda, Masayuki; Sakaida, Hiroshi; Kawaguchi, Kenji; Toma, Naoki; Yamamoto, Akitaka; Hirose, Tomofumi; Miura, Youichi; Fujimoto, Masashi; Matsushima, Satoshi; Taki, Waro

    2009-09-01

    Distal embolism is an important periprocedural technical complication with carotid angioplasty and carotid artery stenting (CAS). We evaluated the safety and efficacy of protection devices used during CAS by detecting new cerebral ischemic lesions using diffusion-weighted magnetic resonance imaging in 95 patients who underwent 98 CAS procedures: 34 using single PercuSurge GuardWire, 31 using double balloon protection, 15 using proximal flow reverse protection devices, 14 using Naviballoon, and 4 using filter anti-embolic devices. Diffusion-weighted imaging was performed preoperatively and postoperatively to evaluate the presence of any new embolic cerebral lesions. Postoperative diffusion-weighted imaging revealed 117 new ischemic lesions. Three patients had new ischemic stroke, two minor and one major, all ipsilateral to the treated carotid artery. The remaining patients had clinically silent ischemia. The incidence of new embolic lesions was lower using the proximal flow reverse protection device than with the double balloon protection (33% vs. 48.4%), but the volume of ipsilateral new ischemic lesions per patient was 136.6 mm(3) vs. 86.9 mm(3), respectively. Neuroprotection with Naviballoon yielded ipsilateral lesions of large volume (86.6 mm(3)) and higher number (5.7 lesions per patient) than using the filter anti-embolic device (34.8 mm(3) and 1 lesion per patient). New cerebral ischemic lesions after neuroprotected CAS are usually silent. The lower incidence of distal ischemia using proximal flow reverse and double balloon protection devices is limited by the larger volume and higher number of ischemic lesions.

  8. Evaluation of Possible Prognostic Factors of Fulminant Acute Disseminated Encephalomyelitis (ADEM) on Magnetic Resonance Imaging with Fluid-Attenuated Inversion Recovery (FLAIR) and Diffusion-Weighted Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Donmez, F.Y.; Aslan, H.; Coskun, M. (Dept. of Radiology, Faculty of Medicine, Baskent Univ., Ankara (Turkey))

    2009-04-15

    Background: Acute disseminated encephalomyelitis (ADEM) may be a rapidly progressive disease with different clinical outcomes. Purpose: To investigate the radiological findings of fulminant ADEM on diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) images, and to correlate these findings with clinical outcome. Material and Methods: Initial and follow-up magnetic resonance imaging (MRI) scans in eight patients were retrospectively evaluated for distribution of lesions on FLAIR images and presence of hemorrhage or contrast enhancement. DWI of the patients was evaluated as to cytotoxic versus vasogenic edema. The clinical records were analyzed, and MRI results and clinical outcome were correlated. Results: Four of the eight patients died, three had full recovery, and one had residual cortical blindness. The distribution of the hyperintense lesions on FLAIR sequence was as follows: frontal (37.5%), parietal (50%), temporal (37.5%), occipital (62.5%), basal ganglia (50%), pons (37.5%), mesencephalon (37.5%), and cerebellum (50%). Three of the patients who died had brainstem involvement. Two patients had a cytotoxic edema, one of whom died, and the other developed cortical blindness. Six patients had vasogenic edema: three of these patients had a rapid progression to coma and died; three of them recovered. Conclusion: DWI is not always helpful for evaluating the evolution or predicting the outcome of ADEM. However, extension of the lesions, particularly brainstem involvement, may have an influence on the prognosis.

  9. Diffusion-weighted magnetic resonance imaging combined with T2-weighted images in the detection of small breast cancer: a single-center multi-observer study.

    Science.gov (United States)

    Wu, Lian-Ming; Chen, Jie; Hu, Jiani; Gu, Hai-Yan; Xu, Jian-Rong; Hua, Jia

    2014-02-01

    Breast cancer is the most common cancer in women worldwide. However, it remains a difficult diagnosis problem to differentiate between benign and malignant breast lesions, especially in small early breast lesions. To assess the diagnostic value of diffusion-weighted imaging (DWI) combined with T2-weighted imaging (T2WI) for small breast cancer characterization. Fifty-eight patients (65 lesions) with a lesion breast magnetic resonance imaging (MRI) including DWI and histological analysis. Three observers with varying experience levels reviewed MRI. The probability of breast cancer in each lesion on MR images was recorded with a 5-point scale. Areas under the receiver-operating characteristic curve (AUCs) were compared by using the Z test; sensitivity and specificity were determined with the Z test after adjusting for data clustering. AUC of T2WI and DWI (Observer 1, 0.95; Observer 2, 0.91; Observer 3, 0.83) was greater than that of T2WI (Observer 1, 0.80; Observer 2, 0.74; Observer 3, 0.70) for all observers (P breast cancer characterization. It should be considered selectively in the preoperative evaluation of patients with small lesions of the breast.

  10. Basic principles of diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Bammer, Roland.

    2003-01-01

    In diffusion-weighted MRI (DWI), image contrast is determined by the random microscopic motion of water protons. During the last years, DWI has become an important modality in the diagnostic work-up of acute ischemia in the CNS. There are also a few promising reports about the application of DWI to other regions in the human body, such as the vertebral column or the abdomen. This manuscript provides an introduction into the basics of DWI and Diffusion Tensor imaging. The potential of various MR sequences in concert with diffusion preparation are discussed with respect to acquisition speed, spatial resolution, and sensitivity to bulk physiologic motion. More advanced diffusion measurement techniques, such as high angular resolution diffusion imaging, are also addressed

  11. Aggressive Angiomyxoma with Diffusion-Weighted Magnetic Resonance Imaging and Dynamic Contrast Enhancement: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    S. Brunelle

    2013-07-01

    Full Text Available Introduction: Aggressive angiomyxoma (AA is a rare benign soft tissue tumour usually affecting the pelvis and perineum of young women. Magnetic resonance imaging (MRI is crucial in the management of AA patients for its diagnostic contribution and for the preoperative assessment of the actual tumour extension. Given the current development of less aggressive therapeutics associated with a higher risk of recurrence, close follow-up with MRI is fundamental after treatment. In this context, diffusion-weighted (DW imaging has already shown high efficacy in the detection of early small relapses in prostate or rectal cancer. Case Report: We report here a case of pelvic AA in a 51-year-old woman examined with dynamic contrast enhancement and DW-MRI, including apparent diffusion coefficient mapping and calculation. Conclusions: To our knowledge, this is the first description of DW-MRI in AA reported in the literature. Here, knowledge about imaging features of AA will be reviewed and expanded.

  12. Aggressive angiomyxoma with diffusion-weighted magnetic resonance imaging and dynamic contrast enhancement: a case report and review of the literature.

    Science.gov (United States)

    Brunelle, S; Bertucci, F; Chetaille, B; Lelong, B; Piana, G; Sarran, A

    2013-05-01

    Aggressive angiomyxoma (AA) is a rare benign soft tissue tumour usually affecting the pelvis and perineum of young women. Magnetic resonance imaging (MRI) is crucial in the management of AA patients for its diagnostic contribution and for the preoperative assessment of the actual tumour extension. Given the current development of less aggressive therapeutics associated with a higher risk of recurrence, close follow-up with MRI is fundamental after treatment. In this context, diffusion-weighted (DW) imaging has already shown high efficacy in the detection of early small relapses in prostate or rectal cancer. We report here a case of pelvic AA in a 51-year-old woman examined with dynamic contrast enhancement and DW-MRI, including apparent diffusion coefficient mapping and calculation. To our knowledge, this is the first description of DW-MRI in AA reported in the literature. Here, knowledge about imaging features of AA will be reviewed and expanded.

  13. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging of bone marrow in healthy individuals

    Energy Technology Data Exchange (ETDEWEB)

    Hillengass, Jens (Dept. of Radiology, German Cancer Research Center, Heidelberg (Germany); Dept. of Hematology, Oncology and Rheumatology, Univ. of Heidelberg (Germany)), e-mail: j.hillengass@dkfz.de; Stieltjes, Bram (Dept. of Radiology, German Cancer Research Center, Heidelberg (Germany)); Baeuerle, Tobias (Dept. of Medical Physics in Radiology, German Cancer Research Center, Heidelberg (Germany)) (and others)

    2011-04-15

    Background: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) displays microcirculation and permeability by application of contrast-media and diffusion-weighted imaging (DWI) is a tool for quantification of cellularity in the investigated area. Recently published examples cover breast cancer, CNS tumors, head and neck cancer, gastrointestinal cancer, prostate cancer as well as hematologic malignancies. Purpose: To investigated the influence of age, sex, and localization of the investigated region on findings of DCE-MRI and DWI. Material and Methods: DCE-MRI-parameters amplitude A and exchange rate constant kep as well as the DWI-parameter ADC of the bone marrow of the lumbar vertebral column of 30 healthy individuals covering the typical range of age of tumor patients were evaluated. ADC was calculated using b=0 and a maximal b value of either 400 or 750 s/mm2. Results: Amplitude A of DCE-MRI decreased with age (P = 0.01) and amplitude A, exchange rate constant kep as well as ADC based on b = 400 s/mm2 and b = 750 s/mm2, respectively, decreased significantly from the first to the fifth lumbar vertebra with P = 0.02, P = 0.05, P = 0.003, and P = 0.002, respectively. Conclusion: Quantitative parameters of functional imaging techniques in bone marrow are influenced by the age of the examined individual and the anatomical location of the investigated region

  14. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging of bone marrow in healthy individuals

    International Nuclear Information System (INIS)

    Hillengass, Jens; Stieltjes, Bram; Baeuerle, Tobias

    2011-01-01

    Background: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) displays microcirculation and permeability by application of contrast-media and diffusion-weighted imaging (DWI) is a tool for quantification of cellularity in the investigated area. Recently published examples cover breast cancer, CNS tumors, head and neck cancer, gastrointestinal cancer, prostate cancer as well as hematologic malignancies. Purpose: To investigated the influence of age, sex, and localization of the investigated region on findings of DCE-MRI and DWI. Material and Methods: DCE-MRI-parameters amplitude A and exchange rate constant kep as well as the DWI-parameter ADC of the bone marrow of the lumbar vertebral column of 30 healthy individuals covering the typical range of age of tumor patients were evaluated. ADC was calculated using b=0 and a maximal b value of either 400 or 750 s/mm2. Results: Amplitude A of DCE-MRI decreased with age (P = 0.01) and amplitude A, exchange rate constant kep as well as ADC based on b = 400 s/mm 2 and b = 750 s/mm 2 , respectively, decreased significantly from the first to the fifth lumbar vertebra with P = 0.02, P = 0.05, P = 0.003, and P = 0.002, respectively. Conclusion: Quantitative parameters of functional imaging techniques in bone marrow are influenced by the age of the examined individual and the anatomical location of the investigated region

  15. The Value of Diffusion-Weighted Imaging in Combination With Conventional Magnetic Resonance Imaging for Improving Tumor Detection for Early Cervical Carcinoma Treated With Fertility-Sparing Surgery.

    Science.gov (United States)

    Li, Xiulei; Wang, Ling; Li, Yong; Song, Peiji

    2017-10-01

    This study aimed to investigate the value of diffusion-weighted imaging (DWI) in combination with conventional magnetic resonance imaging (MRI) for improving tumor detection in young patients treated with fertility-sparing surgery because of early cervical carcinoma. Fifty-four patients with stage Ia or Ib1 cervical carcinoma were enrolled into this study. Magnetic resonance examinations were performed for these patients using conventional MRI (including T1-weighted imaging, T2-weighted imaging, and dynamic contrast-enhanced MRI) and DWI. The apparent diffusion coefficient (ADC) values of cervical carcinoma were analyzed quantitatively and compared with that of adjacent epithelium. Sensitivity, positive predictive value, and accuracy of 2 sets of MRI sequences were calculated on the basis of histologic results, and the diagnostic ability of conventional MRI/DWI combinations was compared with that of conventional MRI. The mean ADC value from cervical carcinoma (mean, 786 × 10 mm/s ± 100) was significantly lower than that from adjacent epithelium (mean, 1352 × 10 mm/s ± 147) (P = 0.01). When the threshold ADC value set as 1010 × 10 mm/s, the sensitivity and specificity for differentiating cervical carcinoma from nontumor epithelium were 78.2% and 67.2%, respectively. The sensitivity and accuracy of conventional MRI for tumor detection were 76.0% and 70.4%, whereas the sensitivity and accuracy of conventional MRI/DWI combinations were 91.7% and 90.7%, respectively. Conventional MRI/DWI combinations revealed a positive predictive value of 97.8% and only 4 false-negative findings. The addition of DWI to conventional MRI considerably improves the sensitivity and accuracy of tumor detection in young patients treated with fertility-sparing surgery, which supports the inclusion quantitative analysis of ADC value in routine MRI protocol before fertility-sparing surgery.

  16. Reduced integration and differentiation of the imitation network in autism: A combined functional connectivity magnetic resonance imaging and diffusion-weighted imaging study.

    Science.gov (United States)

    Fishman, Inna; Datko, Michael; Cabrera, Yuliana; Carper, Ruth A; Müller, Ralph-Axel

    2015-12-01

    Converging evidence indicates that brain abnormalities in autism spectrum disorder (ASD) involve atypical network connectivity, but few studies have integrated functional with structural connectivity measures. This multimodal investigation examined functional and structural connectivity of the imitation network in children and adolescents with ASD, and its links with clinical symptoms. Resting state functional magnetic resonance imaging and diffusion-weighted imaging were performed in 35 participants with ASD and 35 typically developing controls, aged 8 to 17 years, matched for age, gender, intelligence quotient, and head motion. Within-network analyses revealed overall reduced functional connectivity (FC) between distributed imitation regions in the ASD group. Whole brain analyses showed that underconnectivity in ASD occurred exclusively in regions belonging to the imitation network, whereas overconnectivity was observed between imitation nodes and extraneous regions. Structurally, reduced fractional anisotropy and increased mean diffusivity were found in white matter tracts directly connecting key imitation regions with atypical FC in ASD. These differences in microstructural organization of white matter correlated with weaker FC and greater ASD symptomatology. Findings demonstrate atypical connectivity of the brain network supporting imitation in ASD, characterized by a highly specific pattern. This pattern of underconnectivity within, but overconnectivity outside the functional network is in contrast with typical development and suggests reduced network integration and differentiation in ASD. Our findings also indicate that atypical connectivity of the imitation network may contribute to ASD clinical symptoms, highlighting the role of this fundamental social cognition ability in the pathophysiology of ASD. © 2015 American Neurological Association.

  17. Predicting postnatal renal function of prenatally detected posterior urethral valves using fetal diffusion-weighted magnetic resonance imaging with apparent diffusion coefficient determination.

    Science.gov (United States)

    Faure, Alice; Panait, Nicoleta; Panuel, Michel; Alessandrini, Pierre; D'Ercole, Claude; Chaumoitre, Kathia; Merrot, Thierry

    2017-07-01

    The objective of this study was to evaluate the accuracy of fetal diffusion-weighted magnetic resonance imaging with apparent diffusion coefficient (ADC) determination to predict postnatal renal function (nadir creatinine at 1 year and eGFR) of men with posterior urethral valves (PUV). Between 2003 and 2014, 11 MRI were performed on fetuses (between 28 and 32 weeks) in whom second trimester sonography suggested severe bilateral urinary tract anomalies, suspected of PUV. The ADC of the 11 fetuses ranged from 1.3 to 2.86 mm 2  s -1 (median = 1.79 mm 2  s -1 , normal range for fetal kidney: 1.1-1.8). Two pregnancies with ADC > 2.6 mm 2  s -1 were interrupted; the autopsy confirmed PUV and Potter syndrome. For the remaining nine babies, the follow-up was 5.4 years (0.8-10). Four children with abnormal ADC (1.8-2.3) had chronic kidney disease. The remaining five cases with normal nadir creatinine and eGFR had normal ADC. One case with unilateral elevated ADC had a poor ipsilateral renal function on dimercaptosuccinic acid scan. Here, it seems that diffusion-weighted magnetic resonance imaging with ADC determination could be useful in accurately evaluating fetal kidneys in PUV and predicting renal function. It may be an additional, non-invasive method when biologic and sonographic findings are inconclusive, especially in the case of oligohydramnios. Further studies are needed to confirm our data. © 2017 John Wiley & Sons, Ltd. © 2017 John Wiley & Sons, Ltd.

  18. Preoperative CT versus diffusion weighted magnetic resonance imaging of the liver in patients with rectal cancer; a prospective randomized trial

    Directory of Open Access Journals (Sweden)

    Michael P. Achiam

    2016-01-01

    Full Text Available Introduction. Colorectal cancer is one of the most frequent cancers in the world and liver metastases are seen in up to 19% of patients with colorectal cancers. Detection of liver metastases is not only vital for sufficient treatment and survival, but also for a better estimation of prognosis. The aim of this study was to evaluate the feasibility of diffusion weighted MRI of the liver as part of a combined MR evaluation of patients with rectal cancers and compare it with the standard preoperative evaluation of the liver with CT.Methods. Consecutive patients diagnosed with rectal cancers were asked to participate in the study. Preoperative CT and diffusion weighted MR (DWMR were compared to contrast enhanced laparoscopic ultrasound (CELUS.Results. A total of 35 patients were included, 15 patients in Group-1 having the standard CT evaluation of the liver and 20 patients in Group-2 having the standard CT evaluation of the liver and DWMR of the liver. Compared with CELUS, the per-patient sensitivity/specificity was 50/100% for CT, and for DWMR: 100/94% and 100/100% for Reader 1 and 2, respectively. The per-lesion sensitivity of CT and DWMR were 17% and 89%, respectively compared with CELUS. Furthermore, one patient had non-resectable metastases after DWMR despite being diagnosed with resectable metastases after CT. Another patient was diagnosed with multiple liver metastases during CELUS, despite a negative CT-scan.Discussion. DWMR is feasible for preoperative evaluation of liver metastases. The current standard preoperative evaluation with CT-scan results in disadvantages like missed metastases and futile operations. We recommend that patients with rectal cancer, who are scheduled for MR of the rectum, should have a DWMR of the liver performed at the same time.

  19. Magnetic resonance imaging and diffusion-weighted imaging of normal-appearing white matter in children and young adults with tuberous sclerosis complex

    International Nuclear Information System (INIS)

    Arulrajah, Sahayini; Ertan, Gulhan; Tekes, Aylin; Huisman, Thierry A.G.M.; Jordan, Lori; Khaykin, Elizabeth; Izbudak, Izlem

    2009-01-01

    Patients with tuberous sclerosis complex (TSC) frequently present with neurocognitive deficits which may be related to impaired white matter maturation. The purposes of our study were (a) to evaluate the white matter maturation in children and young adults with TSC by comparing the apparent diffusion coefficient (ADC) values of normal-appearing white matter (NAWM) with age-matched healthy controls and (b) to determine the association of NAWM-ADC values with the severity of neurological symptoms in TSC patients. Twenty-three TSC patients who underwent magnetic resonance imaging/diffusion-weighted imaging between January 2000 and January 2009 were studied. ADC values of NAWM were measured in the frontal, parietal, occipital lobes, and in the pons. ADC data were compared with age-matched normative data derived from healthy controls. Patients were neurologically scored by a pediatric neurologist. Two-sample t tests and linear regression were conducted using STATA software. ADC values of NAWM were higher in TSC patients compared with healthy controls; the increase, however, only reached statistical significance in the frontal white matter and pons in the age group between 96 and 144 months and in the right parietal and occipital white matter in the age group above 144 months. There was no significant change in neurological severity score per unit increase in ADC measurement. ADC values of NAWM appear increased in TSC patients. The abnormal ADC values suggest that myelination may be delayed/impaired in TSC patients, which could explain global neurocognitive deficits. Larger prospective studies, including diffusion tensor imaging, are necessary to validate our results. (orig.)

  20. Magnetic resonance imaging and diffusion-weighted imaging of normal-appearing white matter in children and young adults with tuberous sclerosis complex

    Energy Technology Data Exchange (ETDEWEB)

    Arulrajah, Sahayini; Ertan, Gulhan; Tekes, Aylin; Huisman, Thierry A.G.M. [Johns Hopkins Hospital, Division of Pediatric Radiology, Department of Radiology and Radiological Science, Baltimore, MD (United States); Jordan, Lori [Johns Hopkins School of Public Health, Division of Pediatric Neurology, Baltimore, MD (United States); Khaykin, Elizabeth [Johns Hopkins School of Public Health, Department of Mental Health, Baltimore, MD (United States); Izbudak, Izlem [Johns Hopkins Hospital, Division of Neuroradiology, Department of Radiology and Radiological Science, Baltimore, MD (United States)

    2009-11-15

    Patients with tuberous sclerosis complex (TSC) frequently present with neurocognitive deficits which may be related to impaired white matter maturation. The purposes of our study were (a) to evaluate the white matter maturation in children and young adults with TSC by comparing the apparent diffusion coefficient (ADC) values of normal-appearing white matter (NAWM) with age-matched healthy controls and (b) to determine the association of NAWM-ADC values with the severity of neurological symptoms in TSC patients. Twenty-three TSC patients who underwent magnetic resonance imaging/diffusion-weighted imaging between January 2000 and January 2009 were studied. ADC values of NAWM were measured in the frontal, parietal, occipital lobes, and in the pons. ADC data were compared with age-matched normative data derived from healthy controls. Patients were neurologically scored by a pediatric neurologist. Two-sample t tests and linear regression were conducted using STATA software. ADC values of NAWM were higher in TSC patients compared with healthy controls; the increase, however, only reached statistical significance in the frontal white matter and pons in the age group between 96 and 144 months and in the right parietal and occipital white matter in the age group above 144 months. There was no significant change in neurological severity score per unit increase in ADC measurement. ADC values of NAWM appear increased in TSC patients. The abnormal ADC values suggest that myelination may be delayed/impaired in TSC patients, which could explain global neurocognitive deficits. Larger prospective studies, including diffusion tensor imaging, are necessary to validate our results. (orig.)

  1. Diffusion-weighted imaging in acute demyelinating myelopathy

    International Nuclear Information System (INIS)

    Zecca, Chiara; Cereda, Carlo; Tschuor, Silvia; Staedler, Claudio; Nadarajah, Navarajah; Bassetti, Claudio L.; Gobbi, Claudio; Wetzel, Stephan; Santini, Francesco

    2012-01-01

    Diffusion-weighted imaging (DWI) has become a reference MRI technique for the evaluation of neurological disorders. Few publications have investigated the application of DWI for inflammatory demyelinating lesions. The purpose of the study was to describe diffusion-weighted imaging characteristics of acute, spinal demyelinating lesions. Six consecutive patients (two males, four females; aged 28-64 years) with acute spinal cord demyelinating lesions were studied in a prospective case series design from June 2009 to October 2010. We performed magnetic resonance imaging studies from 2 to 14 days from symptom onset on the patients with relapsing remitting multiple sclerosis (n = 3) or clinically isolated syndrome (n = 3). Main outcome measures were diffusion-weighted imaging and apparent diffusion coefficient pattern (ADC) of acute spinal cord demyelinating lesions. All spinal lesions showed a restricted diffusion pattern (DWI+/ADC-) with a 24% median ADC signal decrease. A good correlation between clinical presentation and lesion site was observed. Acute demyelinating spinal cord lesions show a uniform restricted diffusion pattern. Clinicians and neuro-radiologists should be aware that this pattern is not necessarily confirmatory for an ischaemic aetiology. (orig.)

  2. Diffusion-weighted imaging in acute demyelinating myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Zecca, Chiara; Cereda, Carlo; Tschuor, Silvia; Staedler, Claudio; Nadarajah, Navarajah; Bassetti, Claudio L.; Gobbi, Claudio [Ospedale Regionale di Lugano, Servizio di Neurologia e Neuroradiologia, Neurocenter of Southern Switzerland, Lugano (Switzerland); Wetzel, Stephan [Swiss Neuro Institute (SNI), Abteilung fuer Neuroradiologie, Hirslanden Klinik Zuerich, Zuerich (Switzerland); Santini, Francesco [University of Basel Hospital, Division of Radiological Physics, Basel (Switzerland)

    2012-06-15

    Diffusion-weighted imaging (DWI) has become a reference MRI technique for the evaluation of neurological disorders. Few publications have investigated the application of DWI for inflammatory demyelinating lesions. The purpose of the study was to describe diffusion-weighted imaging characteristics of acute, spinal demyelinating lesions. Six consecutive patients (two males, four females; aged 28-64 years) with acute spinal cord demyelinating lesions were studied in a prospective case series design from June 2009 to October 2010. We performed magnetic resonance imaging studies from 2 to 14 days from symptom onset on the patients with relapsing remitting multiple sclerosis (n = 3) or clinically isolated syndrome (n = 3). Main outcome measures were diffusion-weighted imaging and apparent diffusion coefficient pattern (ADC) of acute spinal cord demyelinating lesions. All spinal lesions showed a restricted diffusion pattern (DWI+/ADC-) with a 24% median ADC signal decrease. A good correlation between clinical presentation and lesion site was observed. Acute demyelinating spinal cord lesions show a uniform restricted diffusion pattern. Clinicians and neuro-radiologists should be aware that this pattern is not necessarily confirmatory for an ischaemic aetiology. (orig.)

  3. Feasibility of diffusion-weighted magnetic resonance imaging in patients with juvenile idiopathic arthritis on 1.0-T open-bore MRI

    Energy Technology Data Exchange (ETDEWEB)

    Barendregt, Anouk M.; Nusman, Charlotte M. [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Hemke, Robert; Lavini, Cristina; Maas, Mario [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Amiras, Dimitri [Imperial College Healthcare NHS Trust, Radiology Department, St. Mary' s Hospital, Paddington, London (United Kingdom); Kuijpers, Taco W. [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands)

    2015-12-15

    To evaluate the feasibility of non-invasive diffusion-weighted imaging (DWI) of the knee of children with juvenile idiopathic arthritis (JIA) and, further, to analyze the apparent diffusion coefficient (ADC) levels to distinguish synovium from effusion. Standard magnetic resonance imaging of the knee including post-contrast imaging was obtained in eight patients (mean age, 12 years 8 months, five females) using an open-bore magnetic resonance imaging system (1.0 T). In addition, axially acquired echo-planar DWI datasets (b-values 0, 50, and 600) were prospectively obtained and the diffusion images were post-processed into ADC{sub 50-600} maps. Two independent observers selected a region of interest (ROI) for both synovium and effusion using aligned post-contrast images as landmarks. Mann-Whitney U test was performed to compare ADC synovium and ADC effusion. DWI was successfully obtained in all patients. When data of both observers was combined, ADC synovium was lower than ADC effusion in the ROI in seven out of eight patients (median, 1.92 x 10{sup -3} mm{sup 2}/s vs. 2.40 x 10{sup -3} mm{sup 2}/s, p = 0.006, respectively). Similar results were obtained when the two observers were analyzed separately (observer 1: p = 0.006, observer 2: p = 0.04). In this pilot study, on a patient-friendly 1.0-T open-bore MRI, we demonstrated that DWI may potentially be a feasible non-invasive imaging technique in children with JIA. We could differentiate synovium from effusion in seven out of eight patients based on the ADC of synovium and effusion. However, to select synovium and effusion on DWI, post-contrast images were still a necessity. (orig.)

  4. Diffusion-weighted MR imaging of the brain. 2. ed.

    International Nuclear Information System (INIS)

    Moritani, Toshio; Ekholm, Sven; Westesson, Per-Lennart

    2009-01-01

    This practical-minded text helps the radiologist and the clinician understand diffusion-weighted MR imaging. The book's 15 chapters range from basic principles to interpretation of diffusion-weighted MR imaging and specific disease. In this second edition, diffusion tensor imaging (fractional anisotropy, color map and fiber tractography) is covered and a new chapter, on ''Diffusion-Weighted Imaging of Scalp and Skull Lesions,'' is included. The volume is updated by newly added cases accompanied by radiological and pathological images along with the most recent references. It is aimed at all those who are involved in neuroimaging, including: residents, fellows, staff, as well as neurologists and neurosurgeons. Diffusion-weighted MR imaging is widely accepted as a means to identify acute infarction but also to differentiate many other pathologic conditions. Understanding diffusion-weighted imaging is important for radiologists, neurologists, neurosurgeons as well as radiology technologists. (orig.)

  5. Use of quantitative diffusion-weighted magnetic resonance imaging to predict human papilloma virus status in patients with oropharyngeal squamous cell carcinoma.

    Science.gov (United States)

    Nakahira, Mitsuhiko; Saito, Naoko; Yamaguchi, Hiroshi; Kuba, Kiyomi; Sugasawa, Masashi

    2014-05-01

    Although identification of human papilloma virus (HPV) status in oropharyngeal squamous cell carcinoma (OPSCC) is essential in predicting treatment response, no imaging modality can currently determine whether a tumor is HPV-related. In this retrospective study, 26 patients with OPSCC confined to the lateral wall or the base of tongue underwent neck magnetic resonance imaging, using T1-, T2- and diffusion-weighted imaging (DWI). Apparent diffusion coefficients (ADCs) in a region of interest covering the largest available primary tumor area of OPSCC on a single slice of the ADC map were calculated using two b values (0 and 1,000 s/mm(2)). Mean and minimum ADCs were compared with HPV status, using p16 immunohistochemistry as a surrogate marker for HPV infection. Mean and minimum ADCs for HPV(+) OPSCC were significantly lower than those for HPV(-) OPSCC. A cut-off value of mean ADC for HPV(+) OPSCC of 1.027 × 10(-3) mm(2)/s yielded sensitivity and specificity of 83.33 and 78.57%, respectively. In conclusion, the present study indicates that ADC could be used to predict HPV status in patients with OPSCC.

  6. [Quantitative analysis of diffusion-weighted magnetic resonance images during chemoradiation therapy for cancer of the cervix uteri: Prognostic role of pretreatment diffusion coefficient values].

    Science.gov (United States)

    Kharuzhyk, S A

    2015-01-01

    to carry out a quantitative analysis of diffusion-weighted magnetic resonance images (DWI) in cancer of the cervix uteri (CCU) and to estimate the possibility of using pretreatment measured diffusion coefficient (MDC) to predict chemoradiation therapy (CRT). The investigation prospectively enrolled 46 women with morphologically verified Stages IB-IVB CCU. All the women underwent diffusion-weighted magnetic resonance imaging of pelvic organs before and after treatment. A semiautomatic method was used to determine tumor signal intensity (SI) on DWI at b 1000 s/mm2 (SI b1000) and tumor MDC. The reproducibility of MDC measurements was assessed in 16 randomly selected women. The investigators compared the pretreatment quantitative DWI measures in complete and incomplete regression (CR and IR) groups and the presence and absence of tumor progression during a follow-up. An association of MDC with progression-free and overall survivals (PFS and OS) was determined in the patients. A semiautomatic tumor segmentation framework could determine the pretreatment quantitative DMI measures with minimal time spent and high reproducibility. The mean tumor MDC was 0.82 +/- 0.14 x 10(-3) mm2/s. CR and IR were established in 28 and 18 women, respectively. The MDC < or = 0.83 x 10(-3) mm2/s predicted CR with a sensitivity of 64.3% and a specificity of 77.8% (p=0.007). The median follow-up was 47 months (range, 3-82 months). With the MDC < or = 0.86 x 10(-3) mm2/s, 5-year PFS was 74.1% versus 42.1% with a higher MDC (p=0.023) and 5-year OS was 70.4 and 40.6%, respectively (p=0.021). The survival difference was insignificant in relation to the degree of tumor regression. The pretreatment IS at b1000 was of no prognostic value. The pretreatment tumor MDC may serve as a biomarker for predicting the efficiency of CRT for CCU.

  7. Contrast-enhanced dynamic and diffusion-weighted magnetic resonance imaging at 3.0 T to assess early-stage nasopharyngeal carcinoma.

    Science.gov (United States)

    Ni, Liangping; Liu, Ying

    2018-04-01

    The present study aimed to assess early-stage nasopharyngeal carcinoma (NPC) with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) at 3.0 T. A total of 44 patients newly diagnosed with NPC were included in the present study. All patients underwent MR examination at 3.0 T using DCE-MRI and DWI. The volume transfer constant ( K trans ), flux rate constant between extravascular extracellular space and plasma ( K ep ), the volume of extravascular extracellular space per unit volume of tissue ( V e ) and the apparent diffusion coefficient (ADC) of tumours were investigated. Furthermore, the correlation between clinical stages and ADC value and K trans were analysed. The diagnostic accuracy of K trans and ADC were estimated using receiver operating characteristic curves. NPC stage correlated positively with K trans and negatively with ADC values. Additionally, tumour K trans negatively correlated with ADC value. The sensitivity and accuracy of combined K trans and ADC in distinguishing between stage II and stage III and stage III and IV were higher than the values of either measurement used separately. The present study suggested that K trans and ADC derived from DCE-MRI and DWI may be useful to detect stage early NPC accurately. K trans and ADC in combination were superior than either alone.

  8. Differentiating laryngeal carcinomas from precursor lesions by diffusion-weighted magnetic resonance imaging at 3.0 T: a preliminary study.

    Directory of Open Access Journals (Sweden)

    De-Sheng Shang

    Full Text Available BACKGROUND: Diffusion-weighted magnetic resonance imaging (DWI has been introduced in head and neck cancers. Due to limitations in the performance of laryngeal DWI, including the complex anatomical structure of the larynx leading to susceptibility effects, the value of DWI in differentiating benign from malignant laryngeal lesions has largely been ignored. We assessed whether a threshold for the apparent diffusion coefficient (ADC was useful in differentiating preoperative laryngeal carcinomas from precursor lesions by turbo spin-echo (TSE DWI and 3.0-T magnetic resonance. METHODS: We evaluated DWI and the ADC value in 33 pathologically proven laryngeal carcinomas and 17 precancerous lesions. RESULTS: The sensitivity, specificity, and accuracy were 81.8%, 64.7%, 76.0% by laryngostroboscopy, respectively. The sensitivity, specificity, and accuracy of conventional magnetic resonance imaging were 90.9%, 76.5%, 86.0%, respectively. Qualitative DWI analysis produced sensitivity, specificity, and accuracy values of 100.0, 88.2, and 96.0%, respectively. The ADC values were lower for patients with laryngeal carcinoma (mean 1.195±0.32×10(-3 mm(2/s versus those with laryngeal precancerous lesions (mean 1.780±0.32×10(-3 mm(2/s; P<0.001. ROC analysis showed that the area under the curve was 0.956 and the optimum threshold for the ADC was 1.455×10(-3 mm(2/s, resulting in a sensitivity of 94.1%, a specificity of 90.9%, and an accuracy of 92.9%. CONCLUSIONS: Despite some limitations, including the small number of laryngeal carcinomas included, DWI may detect changes in tumor size and shape before they are visible by laryngostroboscopy. The ADC values were lower for patients with laryngeal carcinoma than for those with laryngeal precancerous lesions. The proposed cutoff for the ADC may help distinguish laryngeal carcinomas from laryngeal precancerous lesions.

  9. Diffusion-weighted magnetic resonance imaging reflects activation of signal transducer and activator of transcription 3 during focal cerebral ischemia/reperfusion

    Directory of Open Access Journals (Sweden)

    Wen-juan Wu

    2017-01-01

    Full Text Available Signal transducer and activator of transcription (STAT is a unique protein family that binds to DNA, coupled with tyrosine phosphorylation signaling pathways, acting as a transcriptional regulator to mediate a variety of biological effects. Cerebral ischemia and reperfusion can activate STATs signaling pathway, but no studies have confirmed whether STAT activation can be verified by diffusion-weighted magnetic resonance imaging (DWI in rats after cerebral ischemia/reperfusion. Here, we established a rat model of focal cerebral ischemia injury using the modified Longa method. DWI revealed hyperintensity in parts of the left hemisphere before reperfusion and a low apparent diffusion coefficient. STAT3 protein expression showed no significant change after reperfusion, but phosphorylated STAT3 expression began to increase after 30 minutes of reperfusion and peaked at 24 hours. Pearson correlation analysis showed that STAT3 activation was correlated positively with the relative apparent diffusion coefficient and negatively with the DWI abnormal signal area. These results indicate that DWI is a reliable representation of the infarct area and reflects STAT phosphorylation in rat brain following focal cerebral ischemia/reperfusion.

  10. Diffusion-weighted magnetic resonance imaging in the characterization of testicular germ cell neoplasms: Effect of ROI methods on apparent diffusion coefficient values and interobserver variability

    Energy Technology Data Exchange (ETDEWEB)

    Tsili, Athina C., E-mail: a_tsili@yahoo.gr [Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece); Ntorkou, Alexandra, E-mail: alexdorkou@hotmail.com [Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece); Astrakas, Loukas, E-mail: astrakas@uoi.gr [Department of Medical Physics, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece); Xydis, Vasilis, E-mail: vxydis@cc.uoi.gr [Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece); Tsampalas, Stavros, E-mail: stamp@gmail.com [Department of Urology, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece); Sofikitis, Nikolaos, E-mail: akrosnin@hotmail.com [Department of Urology, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece); Argyropoulou, Maria I., E-mail: margyrop@cc.uoi.gr [Department of Clinical Radiology, Medical School, University of Ioannina, University Campus, 45110, Ioannina (Greece)

    2017-04-15

    Highlights: • Seminomas have lower mean ADC compared to NSGCNs. • Round ROI is accurate in characterizing TGCNS. • ROI shape has no significant effect on interobserver variability. - Abstract: Introduction: To evaluate the difference in apparent diffusion coefficient (ADC) measurements at diffusion-weighted (DW) magnetic resonance imaging of differently shaped regions-of-interest (ROIs) in testicular germ cell neoplasms (TGCNS), the diagnostic ability of differently shaped ROIs in differentiating seminomas from nonseminomatous germ cell neoplasms (NSGCNs) and the interobserver variability. Materials and methods: Thirty-three TGCNs were retrospectively evaluated. Patients underwent MR examinations, including DWI on a 1.5-T MR system. Two observers measured mean tumor ADCs using four distinct ROI methods: round, square, freehand and multiple small, round ROIs. The interclass correlation coefficient was analyzed to assess interobserver variability. Statistical analysis was used to compare mean ADC measurements among observers, methods and histologic types. Results: All ROI methods showed excellent interobserver agreement, with excellent correlation (P < 0.001). Multiple, small ROIs provided the lower mean ADC in TGCNs. Seminomas had lower mean ADC compared to NSGCNs for each ROI method (P < 0.001). Round ROI proved the most accurate method in characterizing TGCNS. Conclusion: Interobserver variability in ADC measurement is excellent, irrespective of the ROI shape. Multiple, small round ROIs and round ROI proved the more accurate methods for ADC measurement in the characterization of TGCNs and in the differentiation between seminomas and NSGCNs, respectively.

  11. Combined reading of contrast enhanced and diffusion weighted magnetic resonance imaging by using a simple sum score

    Energy Technology Data Exchange (ETDEWEB)

    Baltzer, Anja [Medical University of Vienna (AKH), Department of Anesthesia, Critical Care and Pain Medicine, Vienna (Austria); Dietzel, Matthias [University Hospital Erlangen, Department of Neuroradiology, Erlangen (Germany); Kaiser, Clemens G. [Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany); Baltzer, Pascal A. [Medical University of Vienna (AKH), General Hospital Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria)

    2016-03-15

    To improve specificity of breast MRI by integrating Apparent Diffusion Coefficient (ADC) values with contrast enhanced MRI (CE-MRI) using a simple sum score. Retrospective analysis of a consecutive series of patients referred to breast MRI at 1.5 T for further workup of breast lesions. Reading results of CE-MRI were dichotomized into score 1 (suspicious) or 0 (benign). Lesion's ADC-values (in *10-3 mm2/s) were assigned two different scores: ADC{sub 2}: likely malignant (score +1, ADC ≤ 1), indeterminate (score 0, ADC >1- ≤ 1.4) and likely benign (score -1, ADC > 1.4) and ADC{sub 1}: indeterminate (score 0, ADC ≤ 1.4) and likely benign (score -1, ADC > 1.4). Final added CE-MRI and ADC scores >0 were considered suspicious. Reference standard was histology and imaging follow-up of >24 months. Diagnostic parameters were compared using McNemar tests. A total of 150 lesions (73 malignant) were investigated. Reading of CE-MRI showed a sensitivity of 100 % (73/73) and a specificity of 81.8 % (63/77). Additional integration of ADC scores increased specificity (ADC2/ADC1, P = 0.008/0.001) without causing false negative results. Using a simple sum score, ADC-values can be integrated with CE-MRI of the breast, improving specificity. The best approach is using one threshold to exclude cancer. (orig.)

  12. Diffusion-Weighted Magnetic Resonance Imaging Early After Chemoradiotherapy to Monitor Treatment Response in Head-and-Neck Squamous Cell Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Vandecaveye, Vincent, E-mail: Vincent.Vandecaveye@uzleuven.be [Department of Radiology, University Hospitals Leuven (Belgium); Dirix, Piet [Department of Radiation Oncology, Leuven Cancer Institute, University Hospitals Leuven (Belgium); De Keyzer, Frederik; Op de Beeck, Katya [Department of Radiology, University Hospitals Leuven (Belgium); Vander Poorten, Vincent [Department of Otorhinolaryngology, Head and Neck Surgery, University Hospitals Leuven (Belgium); Hauben, Esther [Department of Pathology, University Hospitals Leuven (Belgium); Lambrecht, Maarten; Nuyts, Sandra [Department of Radiation Oncology, Leuven Cancer Institute, University Hospitals Leuven (Belgium); Hermans, Robert [Department of Radiology, University Hospitals Leuven (Belgium)

    2012-03-01

    Purpose: To evaluate diffusion-weighted imaging (DWI) for assessment of treatment response in head and neck squamous cell carcinoma (HNSCC) three weeks after the end of chemoradiotherapy (CRT). Methods and Materials: Twenty-nine patients with HNSCC underwent magnetic resonance imaging (MRI) prior to and 3 weeks after CRT, including T{sub 2}-weighted and pre- and postcontrast T{sub 1}-weighted sequences and an echo-planar DWI sequence with six b values (0 to 1,000 s/mm{sup 2}), from which the apparent diffusion coefficient (ADC) was calculated. ADC changes 3 weeks posttreatment compared to baseline ( Increment ADC) between responding and nonresponding primary lesions and adenopathies were correlated with 2 years locoregional control and compared with a Mann-Whitney test. In a blinded manner, the Increment ADC was compared to conventional MRI 3 weeks post-CRT and the routinely implemented CT, on average 3 months post-CRT, which used size-related and morphological criteria. Positive and negative predictive values (PPV and NPV, respectively) were compared between the Increment ADC and anatomical imaging. Results: The Increment ADC of lesions with later tumor recurrence was significantly lower than lesions with complete remission for both primary lesions (-2.3% {+-} 0.3% vs. 80% {+-} 41%; p < 0.0001) and adenopathies (19.9% {+-} 32% vs. 63% {+-} 36%; p = 0.003). The Increment ADC showed a PPV of 89% and an NPV of 100% for primary lesions and a PPV of 70% and an NPV of 96% for adenopathies per neck side. DWI improved PPV and NPV compared to anatomical imaging. Conclusion: DWI with the Increment ADC 3 weeks after concluding CRT for HNSCC allows for early assessment of treatment response.

  13. Diffusion-weighted magnetic resonance imaging for pretreatment prediction and monitoring of treatment response of patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy

    International Nuclear Information System (INIS)

    Nilsen, Line; Olsen, Dag Rune; Seierstad, Therese; Fangberget, Anne; Geier, Oliver

    2010-01-01

    Background. For patients with locally advanced breast cancer (LABC) undergoing neoadjuvant chemotherapy (NACT), the European Guidelines for Breast Imaging recommends magnetic resonance imaging (MRI) to be performed before start of NACT, when half of the NACT has been administered and prior to surgery. This is the first study addressing the value of flow-insensitive apparent diffusion coefficients (ADCs) obtained from diffusion-weighted (DW) MRI at the recommended time points for pretreatment prediction and monitoring of treatment response. Materials and methods. Twenty-five LABC patients were included in this prospective study. DW MRI was performed using single-shot spin-echo echo-planar imaging with b-values of 100, 250 and 800 s/mm 2 prior to NACT, after four cycles of NACT and at the conclusion of therapy using a 1.5 T MR scanner. ADC in the breast tumor was calculated from each assessment. The strength of correlation between pretreatment ADC, ADC changes and tumor volume changes were examined using Spearman's rho correlation test. Results. Mean pretreatment ADC was 1.11 ± 0.21 x 10 -3 mm 2 /s. After 4 cycles of NACT, ADC was significantly increased (1.39 ± 0.36 x 10 -3 mm 2 /s; p=0.018). There was no correlation between individual pretreatment breast tumor ADC and MR response measured after four cycles of NACT (p=0.816) or prior to surgery (p=0.620). Conclusion. Pretreatment tumor ADC does not predict treatment response for patients with LABC undergoing NACT. Furthermore, ADC increase observed mid-way in the course of NACT does not correlate with tumor volume changes.

  14. Diffusion-weighted magnetic resonance imaging reveals the effects of different cooling temperatures on the diffusion of water molecules and perfusion within human skeletal muscle

    International Nuclear Information System (INIS)

    Yanagisawa, O.; Fukubayashi, T.

    2010-01-01

    Aim: To evaluate the effect of local cooling on the diffusion of water molecules and perfusion within muscle at different cooling temperatures. Materials and methods: Magnetic resonance diffusion-weighted (DW) images of the leg (seven males) were obtained before and after 30 min cooling (0, 10, and 20 o C), and after a 30 min recovery period. Two types of apparent diffusion coefficient (ADC; ADC1, reflecting both water diffusion and perfusion within muscle, and ADC2, approximating the true water diffusion coefficient) of the ankle dorsiflexors were calculated from DW images. T2-weighted images were also obtained to calculate T2 values of the ankle dorsiflexors. The skin temperature was measured before, during, and after cooling. Results: Both ADC values significantly decreased after cooling under all cooling conditions; the rate of decrease depended on the cooling temperature used (ADC1: -36% at 0 o C, -27.8% at 10 o C, and -22.6% at 20 o C; ADC2: -26% at 0 o C, -21.1% at 10 o C, and -14.6% at 20 o C). These significant decreases were maintained during the recovery period. Conversely, the T2 value showed no significant changes. Under all cooling conditions, skin temperature significantly decreased during cooling; the rate of decrease depended on the cooling temperature used (-74.8% at 0 o C, -51.1% at 10 o C, and -26.8% at 20 o C). Decreased skin temperatures were not restored to pre-cooling values during the recovery period under any cooling conditions. Conclusion: Local cooling decreased the water diffusion and perfusion within muscle with decreased skin temperature; the rates of decrease depended on the cooling temperature used. These decreases were maintained for 30 min after cooling.

  15. Role of diffusion weighted imaging in musculoskeletal infections: Current perspectives

    International Nuclear Information System (INIS)

    Kumar, Yogesh; Khaleel, Mohammad; Boothe, Ethan; Awdeh, Haitham; Wadhwa, Vibhor; Chhabra, Avneesh

    2017-01-01

    Accurate diagnosis and prompt therapy of musculoskeletal infections are important prognostic factors. In most cases, clinical history, examination and laboratory findings help one make the diagnosis, and routine magnetic resonance imaging (MRI) is useful to identify the extent of the disease process. However, in many situations, a routine MRI may not be specific enough especially if the patient cannot receive contrast intravenously, thereby delaying the appropriate treatment. Diffusion-weighted imaging (DWI) can help in many such situations by providing additional information, accurate characterization and defining the extent of the disease, so that prompt treatment can be initiated. In this article, we illustrate the imaging findings of the spectrum of musculoskeletal infections, emphasizing the role of DWI in this domain. (orig.)

  16. Role of diffusion weighted imaging in musculoskeletal infections: Current perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Yogesh [Yale New Haven Health System at Bridgeport Hospital, Department of Radiology, Bridgeport, CT (United States); Khaleel, Mohammad [UT Southwestern Medical Center, Department of Orthopaedic Surgery, Dallas, TX (United States); Boothe, Ethan; Awdeh, Haitham [UT Southwestern Medical Center, Department of Radiology, Dallas, TX (United States); Wadhwa, Vibhor [University of Arkansas for Medical Sciences, Department of Radiology, Little Rock, AR (United States); Chhabra, Avneesh [UT Southwestern Medical Center, Department of Orthopaedic Surgery, Dallas, TX (United States); UT Southwestern Medical Center, Department of Radiology, Dallas, TX (United States)

    2017-01-15

    Accurate diagnosis and prompt therapy of musculoskeletal infections are important prognostic factors. In most cases, clinical history, examination and laboratory findings help one make the diagnosis, and routine magnetic resonance imaging (MRI) is useful to identify the extent of the disease process. However, in many situations, a routine MRI may not be specific enough especially if the patient cannot receive contrast intravenously, thereby delaying the appropriate treatment. Diffusion-weighted imaging (DWI) can help in many such situations by providing additional information, accurate characterization and defining the extent of the disease, so that prompt treatment can be initiated. In this article, we illustrate the imaging findings of the spectrum of musculoskeletal infections, emphasizing the role of DWI in this domain. (orig.)

  17. Diffusion weighted MR imaging of acute Wernicke's encephalopathy

    International Nuclear Information System (INIS)

    Chung, Tae-Ick; Kim, Joong-Seok; Park, Soung-Kyeong; Kim, Beum-Saeng; Ahn, Kook-Jin; Yang, Dong-Won

    2003-01-01

    We report a case of Wernicke's encephalopathy in which diffusion-weighted MR images demonstrated symmetrical hyperintense lesions in the paraventricular area of the third ventricles and medial thalami. Apparent diffusion coefficient mapping showed isointensity in the aforementioned areas. Diffusion-weighted MR images may provide evidence of vasogenic edema associated with thiamine deficiency, proven in the histopathology of experimental animals. In addition, diffusion-weighted MRI has many advantages over T2 or FLARE-weighted brain MRI in detecting structural and functional abnormalities in Wernicke's encephalopathy

  18. Comparison of [11C]choline Positron Emission Tomography With T2- and Diffusion-Weighted Magnetic Resonance Imaging for Delineating Malignant Intraprostatic Lesions

    International Nuclear Information System (INIS)

    Chang, Joe H.; Lim Joon, Daryl; Davis, Ian D.; Lee, Sze Ting; Hiew, Chee-Yan; Esler, Stephen; Gong, Sylvia J.; Wada, Morikatsu; Clouston, David; O'Sullivan, Richard; Goh, Yin P.; Bolton, Damien; Scott, Andrew M.; Khoo, Vincent

    2015-01-01

    Purpose: The purpose of this study was to compare the accuracy of [ 11 C]choline positron emission tomography (CHOL-PET) with that of the combination of T2-weighted and diffusion-weighted (T2W/DW) magnetic resonance imaging (MRI) for delineating malignant intraprostatic lesions (IPLs) for guiding focal therapies and to investigate factors predicting the accuracy of CHOL-PET. Methods and Materials: This study included 21 patients who underwent CHOL-PET and T2W/DW MRI prior to radical prostatectomy. Two observers manually delineated IPL contours for each scan, and automatic IPL contours were generated on CHOL-PET based on varying proportions of the maximum standardized uptake value (SUV). IPLs identified on prostatectomy specimens defined reference standard contours. The imaging-based contours were compared with the reference standard contours using Dice similarity coefficient (DSC), and sensitivity and specificity values. Factors that could potentially predict the DSC of the best contouring method were analyzed using linear models. Results: The best automatic contouring method, 60% of the maximum SUV (SUV 60 ) , had similar correlations (DSC: 0.59) with the manual PET contours (DSC: 0.52, P=.127) and significantly better correlations than the manual MRI contours (DSC: 0.37, P<.001). The sensitivity and specificity values were 72% and 71% for SUV 60 ; 53% and 86% for PET manual contouring; and 28% and 92% for MRI manual contouring. The tumor volume and transition zone pattern could independently predict the accuracy of CHOL-PET. Conclusions: CHOL-PET is superior to the combination of T2W/DW MRI for delineating IPLs. The accuracy of CHOL-PET is insufficient for gland-sparing focal therapies but may be accurate enough for focal boost therapies. The transition zone pattern is a new classification that may predict how well CHOL-PET delineates IPLs

  19. Quantification of synovitis in the cranio-cervical region: Dynamic contrast enhanced and diffusion weighted magnetic resonance imaging in early rheumatoid arthritis-A feasibility follow up study

    Energy Technology Data Exchange (ETDEWEB)

    Jeromel, M., E-mail: miran.jeromel@gmail.com [Institute of Radiology, Department for Neuroradiology, University Medical Centre Ljubljana, Zaloska cesta 2, 1000 Ljubljana (Slovenia); Jevtic, V., E-mail: vladimir.jevtic@mf.uni-lj.si [Medical Faculty Ljubljana, Vrazov trg 2, 1104 Ljubljana (Slovenia); Sersa, I., E-mail: igor.sersa@ijs.si [Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Ambrozic, A., E-mail: ales.ambrozic@mf.uni-lj.si [Department of Rheumatology, University Medical Centre Ljubljana, Vodnikova 62, 1000 Ljubljana (Slovenia); Tomsic, M., E-mail: matija.tomsic@kclj.si [Department of Rheumatology, University Medical Centre Ljubljana, Vodnikova 62, 1000 Ljubljana (Slovenia)

    2012-11-15

    Objective: To test the feasibility of dynamic contrast enhanced (DCEI) and diffusion weighted (DWI) magnetic resonance imaging (MRI) for quantifying synovitis of the cranio-cervical (C-C) region in patients with early rheumatoid arthritis (RA) and neck pain at the beginning and at a six month follow up. Methods: 27 patients with duration of RA of less than 24 months and neck pain were studied with standard qualitative MRI evaluation and two quantitative MRI methods (DCEI and DWI) at the level of atlantoaxial joints. Rate of early enhancement (REE), enhancement gradient (Genh) and apparent diffusion coefficient (ADC) were extracted from DCEI and DWI data. MRI was coupled with clinical assessment and radiographic imaging. Results: Using standard qualitative MRI evaluation, unequivocal active synovitis (grade 2 or 3 contrast enhancement) was proved in 16 (59%) patients at baseline and 14 (54%) at follow up. DCEI and DWI measurements confirmed active synovitis in 25 (93%) patients at baseline and 24 (92%) at follow up. Average REE, Genh and ADC values decreased during follow up, however the difference was not statistically significant (p > 0.05). Both qualitative and quantitative MRI methods confirmed active inflammatory disease in the C-C region following therapy although all clinical criteria showed signs of improvement of the peripheral disease. Conclusions: The study proved the feasibility of DCEI and DWI MRI for quantifying synovitis of the C-C region in patients with early RA and neck pain. Both techniques can be used as additional method for evaluation of synovitis of the C-C region in RA.

  20. Cerebral edema induced in mice by a convulsive dose of soman. Evaluation through diffusion-weighted magnetic resonance imaging and histology

    International Nuclear Information System (INIS)

    Testylier, Guy; Lahrech, Hana; Montigon, Olivier; Foquin, Annie; Delacour, Claire; Bernabe, Denis; Segebarth, Christoph; Dorandeu, Frederic; Carpentier, Pierre

    2007-01-01

    Purpose: In the present study, diffusion-weighted magnetic resonance imaging (DW-MRI) and histology were used to assess cerebral edema and lesions in mice intoxicated by a convulsive dose of soman, an organophosphate compound acting as an irreversible cholinesterase inhibitor. Methods: Three hours and 24 h after the intoxication with soman (172 μg/kg), the mice were anesthetized with an isoflurane/N 2 O mixture and their brain examined with DW-MRI. After the imaging sessions, the mice were sacrificed for histological analysis of their brain. Results: A decrease in the apparent diffusion coefficient (ADC) was detected as soon as 3 h after the intoxication and was found strongly enhanced at 24 h. A correlation was obtained between the ADC change and the severity of the overall brain damage (edema and cellular degeneration): the more severe the damage, the stronger the ADC drop. Anesthesia was shown to interrupt soman-induced seizures and to attenuate edema and cell change in certain sensitive brain areas. Finally, brain water content was assessed using the traditional dry/wet weight method. A significant increase of brain water was observed following the intoxication. Conclusions: The ADC decrease observed in the present study suggests that brain edema in soman poisoning is mainly intracellular and cytotoxic. Since entry of water into Brain was also evidenced, this type of edema is certainly mixed with others (vasogenic, hydrostatic, osmotic). The present study confirms the potential of DW-MRI as a non-invasive tool for monitoring the acute neuropathological consequences (edema and neurodegeneration) of soman-induced seizures

  1. Quantification of synovitis in the cranio-cervical region: Dynamic contrast enhanced and diffusion weighted magnetic resonance imaging in early rheumatoid arthritis—A feasibility follow up study

    International Nuclear Information System (INIS)

    Jeromel, M.; Jevtič, V.; Serša, I.; Ambrožič, A.; Tomšič, M.

    2012-01-01

    Objective: To test the feasibility of dynamic contrast enhanced (DCEI) and diffusion weighted (DWI) magnetic resonance imaging (MRI) for quantifying synovitis of the cranio-cervical (C-C) region in patients with early rheumatoid arthritis (RA) and neck pain at the beginning and at a six month follow up. Methods: 27 patients with duration of RA of less than 24 months and neck pain were studied with standard qualitative MRI evaluation and two quantitative MRI methods (DCEI and DWI) at the level of atlantoaxial joints. Rate of early enhancement (REE), enhancement gradient (Genh) and apparent diffusion coefficient (ADC) were extracted from DCEI and DWI data. MRI was coupled with clinical assessment and radiographic imaging. Results: Using standard qualitative MRI evaluation, unequivocal active synovitis (grade 2 or 3 contrast enhancement) was proved in 16 (59%) patients at baseline and 14 (54%) at follow up. DCEI and DWI measurements confirmed active synovitis in 25 (93%) patients at baseline and 24 (92%) at follow up. Average REE, Genh and ADC values decreased during follow up, however the difference was not statistically significant (p > 0.05). Both qualitative and quantitative MRI methods confirmed active inflammatory disease in the C-C region following therapy although all clinical criteria showed signs of improvement of the peripheral disease. Conclusions: The study proved the feasibility of DCEI and DWI MRI for quantifying synovitis of the C-C region in patients with early RA and neck pain. Both techniques can be used as additional method for evaluation of synovitis of the C-C region in RA.

  2. The Role of Diffusion-Weighted Magnetic Resonance Imaging in the Treatment Response Evaluation of Hepatocellular Carcinoma Patients Treated With Radiation Therapy

    International Nuclear Information System (INIS)

    Yu, Jeong Il; Park, Hee Chul; Lim, Do Hoon; Choi, Yunseon; Jung, Sang Hoon; Paik, Seung Woon; Kim, Seong Hyun; Jeong, Woo Kyoung; Kim, Young Kon

    2014-01-01

    Purpose: We investigated the role of diffusion-weighted magnetic resonance imaging (DW MRI) as a response evaluation indicator for hepatocellular carcinoma (HCC) treated with radiation therapy (RT). Methods and Materials: Inclusion criteria of this retrospective study were DW MRI acquisition within 1 month before and 3 to 5 months after RT. In total, 48 patients were enrolled. Two radiation oncologists measured the apparent diffusion coefficient (ADC). Possible predictive factors, including alteration of the ADC value before and 3 to 5 month after RT, in relation to local progression-free survival (LPFS) were analyzed and compared. Results: Three months after RT, 6 patients (12.5%) showed a complete response, and 27 patients (56.3%) showed a partial response when evaluated using the modified response evaluation criteria in solid tumors (mRECIST). The average ADC ± SD values were 1.21 ± 0.27 ( × 10 −3  mm 2 /s) before and 1.41 ± 0.36 ( × 10 −3  mm 2 /s) after RT (P<.001). The most significant prognostic factor related to LPFS was mRECIST (P<.001). The increment of ADC value (≥20%) was also a significant factor (P=.02), but RECIST (version 1.1; P=.11) was not. When RECIST was combined with the increment of ADC value (≥20%), the LPFS rates were significantly different between the groups (P=.004), and the area under the curve value (0.745) was comparable with that of mRECIST (0.765). Conclusions: ADC value change before and after RT in HCC was closely related to LPFS. ADC value and RECIST may substitute for mRECIST in patients who cannot receive contrast agents

  3. Evaluation of connectivity map-discovered celastrol as a radiosensitizing agent in a murine lung carcinoma model: Feasibility study of diffusion-weighted magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Hong Young Jun

    Full Text Available This study was designed to identify potential radiosensitizing (RS agents for combined radio- and chemotherapy in a murine model of human lung carcinoma, and to evaluate the in vivo effect of the RS agents using diffusion-weighted magnetic resonance imaging (DW-MRI. Radioresistance-associated genes in A549 and H460 cells were isolated on the basis of their gene expression profiles. Celastrol was selected as a candidate RS by using connectivity mapping, and its efficacy in lung cancer radiotherapy was tested. Mice inoculated with A549 carcinoma cells were treated with single ionizing radiation (SIR, single celastrol (SC, or celastrol-combined ionizing radiation (CCIR. Changes in radiosensitization over time were assessed using DW-MRI before and at 3, 6, and 12 days after therapy initiation. The tumors were stained with hematoxylin and eosin at 6 and 12 days after therapy. The percentage change in the apparent diffusion coefficient (ADC value in the CCIR group was significantly higher than that in the SC and SIR group on the 12th day (Mann-Whitney U-test, p = 0.05; Kruskal-Wallis test, p < 0.05. A significant correlation (Spearman's rho correlation coefficient of 0.713, p = 0.001 was observed between the mean percentage tumor necrotic area and the mean ADC values after therapy initiation. These results suggest that the novel radiosensitizing agent celastrol has therapeutic effects when combined with ionizing radiation (IR, thereby maximizing the therapeutic effect of radiation in non-small cell lung carcinoma. In addition, DW-MRI is a useful noninvasive tool to monitor the effects of RS agents by assessing cellularity changes and sequential therapeutic responses.

  4. Serial diffusion-weighted imaging in MELAS

    International Nuclear Information System (INIS)

    Ohshita, T.; Oka, M.; Imon, Y.; Watanabe, C.; Katayama, S.; Yamaguchi, S.; Kajima, T.; Mimori, Y.; Nakamura, S.

    2000-01-01

    Clinical features of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) resemble those of cerebral infarcts, but the pathogenesis of infarct-like lesions is not fully understood. To characterise these infarct-like lesions, we studied two patients with MELAS using diffusion-weighted (DWI) MRI before and after stroke-like episodes and measured the apparent diffusion coefficient (ADC) in the new infarct-like lesions. These gave high signal on DWI and had much higher ADC than normal-appearing regions. The ADC remained high even 30 days after a stroke-like episode then decreased in lesions, with or without abnormality as shown by conventional MRI. We speculate that early elevation of ADC in the acute or subacute phase reflects vasogenic rather than cytotoxic edema. The ADC of the lesions, which disappeared almost completely with clinical improvement, returned to normal levels, which may reflect tissue recovery without severe damage. To our knowledge, this is the first study of DWI in MELAS. (orig.)

  5. Diffusion weighted magnetic resonance imaging: ischemic and traumatic injury of the central nervous system; Diffusionsgewichtete MRI: ischaemische und traumatische Verletzungen des Zentralnervensystems

    Energy Technology Data Exchange (ETDEWEB)

    Huisman, T.A.G.M.; Sorensen, A.G. [Massachusetts General Hospital and Harvard Medical School, Boston (United States). MGH-NMR Center; Hawighorst, H.; Benoit, C.H. [Swiss Paraplegic Center Nottwil (Switzerland). Inst. of Radiology

    2001-12-01

    Diffusion weighted magnetic resonance imaging (DWI) represents a recent development that extends imaging from the depiction of the neuroanatomy into the field of functional and physiologic processes. DWI measures a fundamentally different physiologic parameter than conventional MRI. Image contrast is related to differences in the microscopic motion (diffusion) of water molecules within brain tissue rather than a change in total tissue water. Consequently, DWI can reveal pathology where conventional T1- and T2-weighted MR images are negative. DWI has clinically proven its value in the assessment of acute cerebral stroke and trauma by showing cerebral injury early due to its ability to discriminate between lesions with cytotoxic edema (decreased diffusion) from lesions with vasogenic edema (increased diffusion). Full tensor DWI allows to calculate a variety of functional maps, the most widely used maps include maps of apparent diffusion coefficients and isotropic diffusion. In addition maps of anisotropic diffusion can be calculated which are believed to give information about the integrity and location of fiber tracts. This functional-anatomical information will most probably play an increasingly important role in the early detection of primary and secondary tissue injury from various reasons and could guide and validate current and future neuroprotective treatments. (orig.) [German] Die diffusionsgewichtete Magnetresonanz Tomografie (DWI) stellt ein neues Verfahren dar, welches die Bildgebung von der einfachen Darstellung der Neuroanatomie um das Feld der funktionalen und physiologischen Prozesse erweitert. Im Gegensatz zur konventionellen MRT misst die DWI einen vollkommen anderen physiologischen Parameter. Der Bildkontrast haengt von Unterschieden in der Mikrobewegung (Diffusion) der Wassermolekuele im Hirngewebe ab. Daher kann die DWI pathologische Prozesse aufzeichnen, wo konventionelle T1- und T2-gewichtete MR Bilder unauffaellig bleiben. In der klinischen

  6. Diffusion-weighted magnetic resonance imaging - a new instrument in the diagnosis of Creutzfeldt-Jacob's disease; Diffusjonsvektet magnetisk resonanstomografi - nytt i diagnostikken av Creutzfeldt-Jakobs sykdom

    Energy Technology Data Exchange (ETDEWEB)

    Romi, Fredrik; Smivoll, Alf Inge; Moerk, Sverre; Tysnes, Ole-Bjoern

    2000-07-01

    Creutzfeldt-Jacob's disease (CID) is characterised by rapidly progressive dementia, ataxia, myoclonus and several other neurological deficits. It generally affects older adults and occurs in sporadic, genetic and iatrogenic forms. Death occurs usually within one year after onset of the disease. The diagnosis is based on clinical criteria, neuro physiological and radiological findings and confirmed by post mortal histopathology. During the last two years several cases of CID have been reported with diffusion-weighted magnetic resonance imaging (MR) abnormalities represented by increased signal intensity indicating reduced diffusion in basal ganglia and/or cortex cerebric. These abnormalities seem to be characteristic of CID. We report a case of CID in a 54 year old woman who developed vertigo, nystagmus, ataxia, myoclonus and dementia over a period of eight months. Diffusion-weighted magnetic resonance imaging showed increased signal intensity in corpus striatum and gyrus conguli. The diagnosis was post mortally confirmed with histopathology. (Author) 7 figs., 15 refs.

  7. Comparison of computed tomographic urography, magnetic resonance urography and the combination of diffusion weighted imaging in diagnosis of upper urinary tract cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Guang-yu; Lu, Qing; Wu, Lian-ming [Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China); Zhang, Jin [Department of Urinary Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China); Chen, Xiao-xi [Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China); Xu, Jian-rong, E-mail: renjixujr@163.com [Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, No. 1630, Dongfang Road, Pudong, Shanghai 200120 (China)

    2014-06-15

    Purpose: To evaluate the performance of computed tomographic urography (CTU), static-fluid magnetic resonance urography (static-fluid MRU) and combinations of CTU, static-fluid MRU and diffusion weighted imaging (DWI) in the diagnosis of upper urinary tract cancer. Material and Methods: Between January 2010 and June 2011, patients with suspected UUT cancer underwent CTU, static-fluid MRU and DWI (b = 1000 s/mm{sup 2}) within a 1-week period. The diagnostic performances of CTU, static-fluid MRU and combinations of CTU, static-fluid MRU and DWI for upper urinary tract cancer were prospectively evaluated. The ureteroscopic and histopathologic findings were compared with the imaging findings. Results: Compared to static-fluid MRU alone (sensitivity: 76/75%, reader 1/reader 2), combining DWI with MRI can increase the sensitivity (sensitivity: 84/84%, p = 0.031/p = 0.016) of upper urinary tract cancer diagnosis. CTU had greater sensitivity (95/94%) and accuracy (92/91%) than both static-fluid MRU (sensitivity: p < 0.001/p < 0.001 and accuracy: 83/81%, p = 0.001/p < 0.001) and static-fluid MRU with DWI (sensitivity: p = 0.023/p = 0.039 and accuracy: 87/85%, p = 0.042/p = 0.049) for the diagnosis of upper urinary tract cancers. Compared with CTU alone, CTU with DWI did not significantly increase sensitivity, specificity or accuracy. However, the diagnostic confidence was improved when the combined technique was used (p = 0.031/p = 0.024). Moreover, there was no significant change in sensitivity, specificity, accuracy or diagnostic confidence when static-fluid MRU was used in combination with CTU and DWI. Conclusion: Although there is a potential role for static-fluid MRU and static-fluid MRU with DWI in urinary tract imaging, CTU is still the better choice for the diagnosis of upper urinary tract cancer. Combining DWI with CTU can help improve confidence in upper urinary tract cancer diagnoses.

  8. Diffusion-weighted magnetic resonance imaging of femoral head osteonecrosis in two groups of patients: Legg-Perthes-Calve and Avascular necrosis.

    Science.gov (United States)

    Ozel, Betul Duran; Ozel, Deniz; Ozkan, Fuat; Halefoglu, Ahmet M

    2016-03-01

    The aim of this prospective study was to evaluate the value of diffusion-weighted magnetic resonance imaging (DW-MRI) in patients with osteonecrosis. Patients were divided into two subgroups as avascular necrosis (AVN) of femoral head for adult group and Legg-Calvé-Perthes (LCP) patients for children. Seventeen patients with femoral head AVN (mean age 42.3 years) and 17 patients with LCP (mean age 8.2 years) were included in this study. Diagnosis confirmed with clinical and other imaging procedures among the patients complaining hip pain. DW images were obtained using the single-shot echo planar sequence and had b values of 0, 500, 1000 s/mm(2). The apparent diffusion coefficient (ADC) values were measured from ADC maps in epiphysis of patients with AVN, both from metaphysis and epiphysis in patients with LCP, respectively. Mann-Whitney U test was used to compare ADC values. The mean ADC value of femoral heads (1.285 ± 0.204 × 10(-3) mm(2)/s) was increased in patients with AVN when compared to normal bone tissue (0.209 ± 0.214 × 10(-3) mm(2)/s) (p < 0.01). The mean ADC values (×10(-3) mm(2)/s) of both metaphysis (0.852 ± 0.293) and epiphysis (0.843 ± 0.332) were also increased in patients with LCP and differences were statistically significant (p < 0.01). As a result, osteonecrosis shows increased ADC values. But it is a controversial concept that DWI offers a valuable data to conventional MRI or not. However, as there are report states, there is a correlation between the stage of the disease with ADC values in the LCP disease. DWI is a fast, without-contrast administration technique and provides quantitative values additional to conventional MR techniques; we believe DWI may play an additional assistance to the diagnosis and treatment for LCP patients. Multicentric larger group studies may provide additional data to this issue.

  9. Analysis of ischemic cerebral lesions using 3.0-T diffusion-weighted imaging and magnetic resonance angiography after revascularization surgery for ischemic disease.

    Science.gov (United States)

    Murai, Yasuo; Mizunari, Takayuki; Takagi, Ryo; Amano, Yasuo; Mizumura, Sunao; Komaba, Yuichi; Okubo, Seiji; Kobayashi, Shiro; Teramoto, Akira

    2013-07-01

    Cerebral revascularization surgery (CRS) is increasingly recognized as an important component in the treatment of complex cerebral vascular disease and tumors. CRS requires that the incidence of perioperative neurological complications should be minimized, because CRS for ischemic disease is often not the goal of treatment, but rather a prophylactic surgery. CRS carries the risk of focal postoperative neurological deficits. Little has been established concerning mechanisms of post-CRS ischemia. We used 3.0-T diffusion-weighted magnetic resonance imaging (DWI) and magnetic resonance angiography (MRA) to analyze the incidence and mechanism of ischemic lesions. We studied the anterior circulation territory after 20 CRS procedures involving 33 vascular anastomosis procedures (13 double anastomoses and 7 single anastomoses) in 12 men and 8 women between June 2007 and October 2011. The operations included single or double superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis to treat internal carotid artery/MCA occlusions or severe MCA stenosis. A combined STA-MCA anastomosis and indirect bypass were performed for moyamoya disease. Postoperative DWI and MRA were obtained in all patients between 24 and 96 h after surgery to detect thromboembolism, hypoperfusion, or procedural ischemic complications and vasospasms of the donor STA. Follow-up DWI and MRA were carried out 1.8±0.6 days after CRS (range, 1-4 days). Temporary occlusion time for anastomoses averaged 18.9 min (range, 16-32 min). Asymptomatic new hyperintensities occurred in the ipsilateral hemisphere of 2 patients on postoperative DWI (10% patients/6.0% anastomoses), and 1 moyamoya patient (5.0% patients/3.0% anastomoses) developed a symptomatic hyperintensity in the ipsilateral occipital lobe in response to the operation. Two abnormal small (3.0-T DWI study of CRS and related clinical events. The incidence of symptomatic postoperative DWI abnormalities was restricted to 1 moyamoya patient

  10. The use of FDG-PET/CT and diffusion-weighted magnetic resonance imaging for response prediction before, during and after preoperative chemoradiotherapy for rectal cancer

    International Nuclear Information System (INIS)

    Lambrecht, Maarten; Roels, Sarah; Haustermans, Karin; Deroose, Christophe; Vandecaveye, Vincent; Keyzer, Frederik de; Penninckx, Freddy; Sagaert, Xavier; Cutsem, Eric van

    2010-01-01

    Purpose. To investigate the use of FDG-PET/CT before, during and after chemoradiotherapy (CRT) and diffusion-weighted magnetic resonance imaging (DW-MRI) before CRT for the prediction of pathological response (pCR) in rectal cancer patients. Material and methods. Twenty-two rectal cancer patients treated with long course CRT were included. An FDG-PET/CT was performed prior to the start of CRT, after 10 to 12 fractions of CRT and five weeks after the end of CRT. The tumor was delineated using a gradient based delineation method and the maximal standardized uptake values (SUV max ) were calculated. A DW-MRI was performed before start of CRT. Mean apparent diffusion coefficients (ADC) were determined. The ΔSUV max during and after CRT and the initial ADC values were correlated to the histopathological findings after total mesorectal excision (TME). Results. ΔSUV max during and after CRT significantly correlated with the pathological response to treatment (during CRT: ΔSUV max = 59% ± 12% for pCR vs. 25% ± 27% if no pCR, p=0.0036; post-CRT: 90% ± 11 for pCR vs. 63% ± 22 if no pCR p=0.013). ROC curve analysis revealed an optimal threshold for ΔSUV max of 40% during CRT and 76% after CRT. The initial ADC value was also significantly correlated with pCR (0.94 ± 0.12 x 10-3 mm 2 /s for pCR vs. 1.2 ± 0.24 x 10-3 mm 2 /s, p=0.002) and ROC curve analysis revealed an optimal threshold of 1.06 x 10-3 mm 2 /s. Combining the provided ΔSUV max thresholds during and after CRT increased specificity of the prediction (sensitivity 100% and specificity 94%). The combination of the thresholds for the initial ADC value and the ΔSUV max during CRT increased specificity of the prediction to a similar level (sensitivity of 100% and specificity of 94%). Conclusions. The combination of the different time points and the different imaging modalities increased the specificity of the response assessment both during and after CRT.

  11. Diagnostic value of whole-body diffusion-weighted magnetic resonance imaging for detection of primary and metastatic malignancies: A meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bin, E-mail: lllb146@163.com [Department of Radiology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003 (China); Li, Qiong [Department of Radiology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003 (China); Nie, Wei [Department of Respiratory Disease, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003 (China); Liu, Shiyuan, E-mail: lsy20112077@163.com [Department of Radiology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003 (China)

    2014-02-15

    Purpose: To perform a meta-analysis to evaluate the diagnostic performance of whole-body diffusion-weighted magnetic resonance imaging (WB-DWI) technique in detection of primary and metastatic malignancies compared with that of whole-body positron emission tomography/computed tomography (WB-PET/CT). Materials and methods: Search Pubmed, MEDLINE, EMBASE and Cochrane Library database from January 1984 to July 2013 for studies comparing WB-DWI with WB-PET/CT for detection of primary and metastatic malignancies. Methodological quality was assessed by the quality assessment of diagnostic studies (QUADAS) instrument. Sensitivities, specificities, predictive values, diagnostic odds ratio (DOR) and areas under the summary receiver operator characteristic curve (AUC) were calculated. Potential threshold effect, heterogeneity and publication bias were investigated. Result: Thirteen eligible studies were included, with a total of 1067 patients. There was no significant threshold effect. WB-DWI had a similar AUC (0.966 (95% CI, 0.940–0.992) versus 0.984 (95% CI, 0.965–0.999)) with WB-PET/CT. No significant difference was detected between AUC of WB-DWI and WB-PET/CT. WB-DWI had a pooled sensitivity of 0.897 (95% CI, 0.876–0.916) and a pooled specificity of 0.954 (95% CI, 0.944–0.962). WB-PET/CT had a pooled sensitivity of 0.895 (95% CI, 0.865–0.920) and a pooled specificity of 0.975 (95% CI, 0.966–0.981). Heterogeneity was found to stem primarily from data type (per lesion versus per patient), MR sequence (DWIBS only and DWIBS with other sequence), and primary lesion type (single type and multiple type). The Deeks's funnel plots suggested the absence of publication bias. Conclusion: WB-DWI has similar, good diagnostic performance for the detection of primary and metastatic malignancies compared with WB-PET/CT. DWIBS with other MR sequences could further improve the diagnostic performance. More high-quality studies regarding comparison of WB-DWI and WB

  12. Quantitative and qualitative evaluation of brain diffusion weighted magnetic resonance imaging comparison with 1.5 T and 3.0 T units

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Eun Hoe [Dept. of Radiological Science, Cheongju University, Cheongju (Korea, Republic of); Dong, Kyung Rae [Dept. of Radiological Technology, Gwangju Health University, Gwangju (Korea, Republic of)

    2017-02-15

    DWI of biological effects are independent of magnetic field strength in various regions. High field strength, however, does affect the signal to noise ratio (SNR) and artifacts of diffusion weighted imaging (DWI) images, which ultimately will influence the quantitative of diffusion imaging . In this study, the effects of field strength on DWI are reviewed. The effects of the diseases also are discussed. Comparing DWI in cerebellum, WM, GM, Hyperacute region measurements both as a function of field strength (1.5 T and 3.0 T). Overall, the SNR of the DWI roughly doubled going from 1.5 T to 3.0 T. In summary, DWI studies at 3.0 T is provided significantly improved DWI measurements relative to studies at 1.5 T.

  13. Physiological Background of Differences in Quantitative Diffusion-Weighted Magnetic Resonance Imaging Between Acute Malignant and Benign Vertebral Body Fractures: Correlation of Apparent Diffusion Coefficient With Quantitative Perfusion Magnetic Resonance Imaging Using the 2-Compartment Exchange Model.

    Science.gov (United States)

    Geith, Tobias; Biffar, Andreas; Schmidt, Gerwin; Sourbron, Steven; Dietrich, Olaf; Reiser, Maximilian; Baur-Melnyk, Andrea

    2015-01-01

    To test the hypothesis that apparent diffusion coefficient (ADC) in vertebral bone marrow of benign and malignant fractures is related to the volume of the interstitial space, determined with dynamic contrast-enhanced (DCE) magnetic resonance imaging. Patients with acute benign (n = 24) and malignant (n = 19) vertebral body fractures were examined at 1.5 T. A diffusion-weighted single-shot turbo-spin-echo sequence (b = 100 to 600 s/mm) and DCE turbo-FLASH sequence were evaluated. Regions of interest were manually selected for each fracture. Apparent diffusion coefficient was determined with a monoexponential decay model. The DCE magnetic resonance imaging concentration-time curves were analyzed using a 2-compartment tracer-kinetic model. Apparent diffusion coefficient showed a significant positive correlation with interstitial volume in the whole study population (Pearson r = 0.66, P correlation between ADC and the permeability-surface area product could be observed when analyzing the whole study population (Spearman rs = 0.40, P = 0.008), but not when separately examining the subgroups. Plasma flow showed a significant correlation with ADC in benign fractures (Pearson r = 0.23, P = 0.03). Plasma volume did not show significant correlations with ADC. The results support the hypothesis that the ADC of a lesion is inversely correlated to its cellularity. This explains previous observations that ADC is reduced in more malignant lesions.

  14. Comparison of PET-CT and magnetic resonance diffusion weighted imaging with body suppression (DWIBS) for initial staging of malignant lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Stéphane, Velasco, E-mail: stephane.velasco@chu-poitiers.fr [Department of Radiology, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France); Samuel, Burg, E-mail: s.burg@chu-poitiers.fr [Department of Nuclear Medicine, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France); Department of Nuclear Medicine, Saint-Louis Hospital, Paris CHU Saint Louis, 40 rue de Bichat, 75 010 Paris (France); Vincent, Delwail, E-mail: v.delwail@chu-poitiers.fr [Department of Hematology, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France); Joelle, Guilhot, E-mail: j.guilhot@chu-poitiers.fr [Department of Hematology, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France); Remy, Perdrisot, E-mail: r.perdrisot@chu-poitiers.fr [Department of Nuclear Medicine, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France); Francois, Guilhot Gaudeffroy, E-mail: f.guilhot-gaudeffroy@chu-poitiers.fr [Department of Hematology, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France); Jean-Pierre, Tasu, E-mail: j.p.tasu@chu-poitiers.fr [Department of Radiology, CHU de Poitiers, rue de la milétrie, 86000 Poitiers (France)

    2013-11-01

    Objective: To evaluate the clinical impact of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in staging of malignant lymphoma. Methods: Twenty-three patients with proven malignant lymphomas were prospectively enrolled. DWIBS (b = 0, 1000 s/mm{sup 2}) examinations and PET-CT were performed respectively on an Intera 1.5 T unit and a Gyroscan PET-CT scan (Philips Medical system, Best, the Netherland). The criteria for positive node involvement were a size over 10 mm or an apparent diffusion coefficient (ADC) value under 0.75 10{sup −3} mm{sup 2}/s for nodes under 10 mm. For extranodal analysis, a high or heterogeneous signal on DWIBS was considered as positive. In cases of discordance, the reference standard for each region or organ was established at 6 months after the diagnosis according to all available clinical, biological information, as well as histological evidence or follow-up to prove or disprove the presence of disease. Results: DWIBS and PET-CT results were congruent in 333 node regions on the 345 areas analyzed, with excellent agreement (κ = 0.97, P < 0.0001). From 433 organs analyzed (one patient had splenectomy) extranodal disease was detected in 22 organs on DWIBS. The two imaging techniques agreed on 430 organs (κ = 0.99, P < 0.0001). Finally, Ann Arbor stages based on DWIBS and those of PET/CT were in agreement for 23 patients. Conclusions: For malignant lymphoma in a pre-therapeutic context, agreement between diffusion-weighted whole-body imaging and PET/CT is high for Ann Arbor staging.

  15. Comparison of PET-CT and magnetic resonance diffusion weighted imaging with body suppression (DWIBS) for initial staging of malignant lymphomas

    International Nuclear Information System (INIS)

    Stéphane, Velasco; Samuel, Burg; Vincent, Delwail; Joelle, Guilhot; Remy, Perdrisot; Francois, Guilhot Gaudeffroy; Jean-Pierre, Tasu

    2013-01-01

    Objective: To evaluate the clinical impact of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in staging of malignant lymphoma. Methods: Twenty-three patients with proven malignant lymphomas were prospectively enrolled. DWIBS (b = 0, 1000 s/mm 2 ) examinations and PET-CT were performed respectively on an Intera 1.5 T unit and a Gyroscan PET-CT scan (Philips Medical system, Best, the Netherland). The criteria for positive node involvement were a size over 10 mm or an apparent diffusion coefficient (ADC) value under 0.75 10 −3 mm 2 /s for nodes under 10 mm. For extranodal analysis, a high or heterogeneous signal on DWIBS was considered as positive. In cases of discordance, the reference standard for each region or organ was established at 6 months after the diagnosis according to all available clinical, biological information, as well as histological evidence or follow-up to prove or disprove the presence of disease. Results: DWIBS and PET-CT results were congruent in 333 node regions on the 345 areas analyzed, with excellent agreement (κ = 0.97, P < 0.0001). From 433 organs analyzed (one patient had splenectomy) extranodal disease was detected in 22 organs on DWIBS. The two imaging techniques agreed on 430 organs (κ = 0.99, P < 0.0001). Finally, Ann Arbor stages based on DWIBS and those of PET/CT were in agreement for 23 patients. Conclusions: For malignant lymphoma in a pre-therapeutic context, agreement between diffusion-weighted whole-body imaging and PET/CT is high for Ann Arbor staging

  16. Early diffusion weighted magnetic resonance imaging can predict survival in women with locally advanced cancer of the cervix treated with combined chemo-radiation

    International Nuclear Information System (INIS)

    Somoye, Gbolahan; Parkin, David; Harry, Vanessa; Semple, Scott; Plataniotis, George; Scott, Neil; Gilbert, Fiona J.

    2012-01-01

    To assess the predictive value of diffusion weighted imaging (DWI) for survival in women treated for advanced cancer of the cervix with concurrent chemo-radiotherapy. Twenty women treated for advanced cancer of the cervix were recruited and followed up for a median of 26 (range -3 /mm 2 /s), respectively, P = 0.02. The median change in ADC 14 days after treatment commencement was significantly higher in the alive group compared to non-survivors, 0.28 and 0.14 (x 10 -3 /mm 2 /s), respectively, P = 0.02. There was no evidence of a difference between survivors and non-survivors for pretreatment baseline or post-therapy ADC values. Functional DWI early in the treatment of advanced cancer of the cervix may provide useful information in predicting survival. (orig.)

  17. Acoustic-noise-optimized diffusion-weighted imaging.

    Science.gov (United States)

    Ott, Martin; Blaimer, Martin; Grodzki, David M; Breuer, Felix A; Roesch, Julie; Dörfler, Arnd; Heismann, Björn; Jakob, Peter M

    2015-12-01

    This work was aimed at reducing acoustic noise in diffusion-weighted MR imaging (DWI) that might reach acoustic noise levels of over 100 dB(A) in clinical practice. A diffusion-weighted readout-segmented echo-planar imaging (EPI) sequence was optimized for acoustic noise by utilizing small readout segment widths to obtain low gradient slew rates and amplitudes instead of faster k-space coverage. In addition, all other gradients were optimized for low slew rates. Volunteer and patient imaging experiments were conducted to demonstrate the feasibility of the method. Acoustic noise measurements were performed and analyzed for four different DWI measurement protocols at 1.5T and 3T. An acoustic noise reduction of up to 20 dB(A) was achieved, which corresponds to a fourfold reduction in acoustic perception. The image quality was preserved at the level of a standard single-shot (ss)-EPI sequence, with a 27-54% increase in scan time. The diffusion-weighted imaging technique proposed in this study allowed a substantial reduction in the level of acoustic noise compared to standard single-shot diffusion-weighted EPI. This is expected to afford considerably more patient comfort, but a larger study would be necessary to fully characterize the subjective changes in patient experience.

  18. Diffusion-weighted MR imaging of intracranial tumors

    International Nuclear Information System (INIS)

    Bydder, G.M.; Baudouin, C.J.; Steiner, R.E.; Hajnal, J.V.; Young, I.R.

    1991-01-01

    This paper assesses the effect of anisotropic diffusion weighting on the appearances of cerebral tumors as well as vasogenic and interstitial edema. Diffusion weighting produced a reduction in signal intensity in all or part of the tumors in the majority of cases. However, a relative increase in signal intensity was apparent in four cases. The decrease in signal intensity in vasogenic edema depended on the site and direction of gradient sensitization. Marked increase in conspicuity between tumor and edema was apparent in three cases. Changes in interstitial edema depended in detail in fiber direction. Differentiation between tumor and edema can be improved with diffusion-weighted imaging. Anisotropic change is seen in both vasogenic and interstitial edema

  19. Dynamic Contrast Magnetic Resonance Imaging (DCE-MRI) and Diffusion Weighted MR Imaging (DWI) for Differentiation between Benign and Malignant Salivary Gland Tumors

    OpenAIRE

    Assili, S.; Fathi Kazerooni, A.; Aghaghazvini, L.; Saligheh Rad, H.R.; Pirayesh Islamian, J.

    2015-01-01

    Background: Salivary gland tumors form nearly 3% of head and neck tumors. Due to their large histological variety and vicinity to facial nerves, pre-operative diagnosis and differentiation of benign and malignant parotid tumors are a major challenge for radiologists. Objective: The majority of these tumors are benign; however, sometimes they tend to transform into a malignant form. Functional MRI techniques, namely dynamic contrast enhanced (DCE-) MRI and diffusion-weighted ...

  20. A time-efficient acquisition protocol for multipurpose diffusion-weighted microstructural imaging at 7 Tesla.

    Science.gov (United States)

    Sepehrband, Farshid; O'Brien, Kieran; Barth, Markus

    2017-12-01

    Several diffusion-weighted MRI techniques have been developed and validated during the past 2 decades. While offering various neuroanatomical inferences, these techniques differ in their proposed optimal acquisition design, preventing clinicians and researchers benefiting from all potential inference methods, particularly when limited time is available. This study reports an optimal design that enables for a time-efficient diffusion-weighted MRI acquisition scheme at 7 Tesla. The primary audience of this article is the typical end user, interested in diffusion-weighted microstructural imaging at 7 Tesla. We tested b-values in the range of 700 to 3000 s/mm 2 with different number of angular diffusion-encoding samples, against a data-driven "gold standard." The suggested design is a protocol with b-values of 1000 and 2500 s/mm 2 , with 25 and 50 samples, uniformly distributed over two shells. We also report a range of protocols in which the results of fitting microstructural models to the diffusion-weighted data had high correlation with the gold standard. We estimated minimum acquisition requirements that enable diffusion tensor imaging, higher angular resolution diffusion-weighted imaging, neurite orientation dispersion, and density imaging and white matter tract integrity across whole brain with isotropic resolution of 1.8 mm in less than 11 min. Magn Reson Med 78:2170-2184, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  1. Diffusion-weighted magnetic resonance imaging predicts survival in patients with liver-predominant metastatic colorectal cancer shortly after selective internal radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Schmeel, Frederic Carsten; Simon, Birgit; Luetkens, Julian Alexander; Traeber, Frank; Schmeel, Leonard Christopher; Schild, Hans Heinz; Hadizadeh, Dariusch Reza [University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universitaet Bonn, Department of Radiology, Bonn (Germany); Sabet, Amir [University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universitaet Bonn, Department of Nuclear Medicine, Bonn (Germany); University Hospital Essen, Universitaet Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); Ezziddin, Samer [University Hospital Bonn, Rheinische-Friedrich-Wilhelms-Universitaet Bonn, Department of Nuclear Medicine, Bonn (Germany); University Hospital Saarland, Universitaet des Saarlandes, Department of Nuclear Medicine, Homburg (Germany)

    2017-03-15

    To investigate whether quantifications of apparent diffusion coefficient (ADC) on diffusion-weighted imaging (DWI) can predict overall survival (OS) in patients with liver-predominant metastatic colorectal cancer (CRC) following selective internal radiation therapy with {sup 90}Yttrium-microspheres (SIRT). Forty-four patients underwent DWI 19 ± 16 days before and 36 ± 10 days after SIRT. Tumour-size and intratumoral minimal ADC (minADC) values were measured for 132 liver metastases on baseline and follow-up DWI. Optimal functional imaging response to treatment was determined by receiver operating characteristics and defined as ≥22 % increase in post-therapeutic minADC. Survival analysis was performed with the Kaplan-Meier method and Cox-regression comparing various variables with potential impact on OS. Median OS was 8 months. The following parameters were significantly associated with median OS: optimal functional imaging response (18 vs. 5 months; p < 0.001), hepatic tumour burden <50 % (8 vs. 5 months; p = 0.018), Eastern Cooperative Oncology Group performance scale <1 (10 vs. 4 months; p = 0.012) and progressive disease according to Response and Evaluation Criteria in Solid Tumours (8 vs. 3 months; p = 0.001). On multivariate analysis, optimal functional imaging response and hepatic tumour burden remained independent predictors of OS. Functional imaging response assessment using minADC changes on DWI may predict survival in CRC shortly after SIRT. (orig.)

  2. Reduced field-of -view diffusion-weighted magnetic resonance imaging of the pancreas: Comparison with conventional single-shot echo-planar imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Jin; Lee, Jeong Min; Yoon, Jeong Hee; Jang, Jin Young; Kim, Sun Whe; Ryu, Ji Kon; Han, Joon Koo; Choi, Byung Ihn [Seoul National University Hospital, Seoul (Korea, Republic of); Kannengiesser, Stephan [Siemens Healthcare, Erlangen (Germany)

    2015-12-15

    To investigate the image quality (IQ) and apparent diffusion coefficient (ADC) of reduced field-of-view (FOV) diffusion-weighted imaging (DWI) of pancreas in comparison with full FOV DWI. In this retrospective study, 2 readers independently performed qualitative analysis of full FOV DWI (FOV, 38 × 38 cm; b-value, 0 and 500 s/mm{sup 2}) and reduced FOV DWI (FOV, 28 × 8.5 cm; b-value, 0 and 400 s/mm{sup 2}). Both procedures were conducted with a two-dimensional spatially selective radiofrequency excitation pulse, in 102 patients with benign or malignant pancreatic diseases (mean size, 27.5 ± 14.4 mm). The study parameters included 1) anatomic structure visualization, 2) lesion conspicuity, 3) artifacts, 4) IQ score, and 5) subjective clinical utility for confirming or excluding initially considered differential diagnosis on conventional imaging. Another reader performed quantitative ADC measurements of focal pancreatic lesions and parenchyma. Wilcoxon signed-rank test was used to compare qualitative scores and ADCs between DWI sequences. Mann Whitney U-test was used to compare ADCs between the lesions and parenchyma. On qualitative analysis, reduced FOV DWI showed better anatomic structure visualization (2.76 ± 0.79 at b = 0 s/mm{sup 2} and 2.81 ± 0.64 at b = 400 s/mm{sup 2}), lesion conspicuity (3.11 ± 0.99 at b = 0 s/mm{sup 2} and 3.15 ± 0.79 at b = 400 s/mm{sup 2}), IQ score (8.51 ± 2.05 at b = 0 s/mm{sup 2} and 8.79 ± 1.60 at b = 400 s/mm{sup 2}), and higher clinical utility (3.41 ± 0.64), as compared to full FOV DWI (anatomic structure, 2.18 ± 0.59 at b = 0 s/mm{sup 2} and 2.56 ± 0.47 at b = 500 s/mm{sup 2}; lesion conspicuity, 2.55 ± 1.07 at b = 0 s/mm{sup 2} and 2.89 ± 0.86 at b = 500 s/mm{sup 2}; IQ score, 7.13 ± 1.83 at b = 0 s/mm{sup 2} and 8.17 ± 1.31 at b = 500 s/mm{sup 2}; clinical utility, 3.14 ± 0.70) (p < 0.05). Artifacts were significantly improved on reduced FOV DWI (2.65 ± 0.68) at b = 0 s/mm{sup 2} (full FOV DWI, 2.41 ± 0.63) (p

  3. Diffusion-weighted MR imaging in transient ischaemic attacks

    Energy Technology Data Exchange (ETDEWEB)

    Lamy, C.; Calvet, D.; Domigo, V.; Mas, J. [de l' Hopital Sainte-Anne, Service de Neurologie, Paris Cedex 14 (France); Oppenheim, C.; Naggara, O.; Meder, J.F. [Hoepital Sainte-Anne, Departement d' Imagere Morphologique et Fonchonnille, Paris (France)

    2006-05-15

    The purpose of this study was to determine frequency and the characteristics of diffusion-weighted imaging (DWI) abnormalities in patients with transient ischaemic attack (TIA). We analysed data of 98 consecutive patients (mean age: 60.6{+-}15.4 years, 56 men) admitted between January 2003 and April 2004 for TIA. Age, gender, symptom type and duration, delay from onset to magnetic resonance imaging (MRI), probable or possible TIA and cause of TIA were compared in patients with (DWI+) and without (DWI-) lesions on DWI. Volume and apparent diffusion coefficient (ADC) values of DWI lesions were computed. DWI revealed ischaemic lesions in 34 patients (34.7%). Lesions were small (mean volume: 1.9 cm{sup 3}{+-}3.3), and ADC was moderately decreased (mean ADC ratio: 79.5%). The diagnosis of TIA was considered as probable in all DWI+ patients. A multiple logistic regression model demonstrated that TIA duration greater than or equal to 60 min (OR, 7.6; 95% CI, 2.3-25.7), aphasia (OR, 9.2; 95% CI, 2.7-31.4) and motor deficit (OR, 5.1; 95% CI, 1.5-17.8) were independent predictors of DWI lesions. Prolonged TIA duration, aphasia and motor deficits are associated with DWI lesions. More than half of TIA patients with symptoms lasting more than 60 min have DWI lesions. (orig.)

  4. Diffusion-weighted MR imaging in transient ischaemic attacks

    International Nuclear Information System (INIS)

    Lamy, C.; Calvet, D.; Domigo, V.; Mas, J.; Oppenheim, C.; Naggara, O.; Meder, J.F.

    2006-01-01

    The purpose of this study was to determine frequency and the characteristics of diffusion-weighted imaging (DWI) abnormalities in patients with transient ischaemic attack (TIA). We analysed data of 98 consecutive patients (mean age: 60.6±15.4 years, 56 men) admitted between January 2003 and April 2004 for TIA. Age, gender, symptom type and duration, delay from onset to magnetic resonance imaging (MRI), probable or possible TIA and cause of TIA were compared in patients with (DWI+) and without (DWI-) lesions on DWI. Volume and apparent diffusion coefficient (ADC) values of DWI lesions were computed. DWI revealed ischaemic lesions in 34 patients (34.7%). Lesions were small (mean volume: 1.9 cm 3 ±3.3), and ADC was moderately decreased (mean ADC ratio: 79.5%). The diagnosis of TIA was considered as probable in all DWI+ patients. A multiple logistic regression model demonstrated that TIA duration greater than or equal to 60 min (OR, 7.6; 95% CI, 2.3-25.7), aphasia (OR, 9.2; 95% CI, 2.7-31.4) and motor deficit (OR, 5.1; 95% CI, 1.5-17.8) were independent predictors of DWI lesions. Prolonged TIA duration, aphasia and motor deficits are associated with DWI lesions. More than half of TIA patients with symptoms lasting more than 60 min have DWI lesions. (orig.)

  5. Diffusion-weighted imaging in normal fetal brain maturation

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, J.F. [University Children' s Hospital UKBB, Department of Pediatric Radiology, Basel (Switzerland); Confort-Gouny, S.; Le Fur, Y.; Viout, P.; Cozzone, P. [UMR-CNRS 6612, Faculte de Medecine, Universite de la Mediterranee, Centre de Resonance Magnetique Biologique et Medicale, Marseille (France); Bennathan, M.; Chapon, F.; Fogliarini, C.; Girard, N. [Universite de la Mediterranee, Department of Neuroradiology AP-HM Timone, Marseille (France)

    2007-09-15

    Diffusion-weighted imaging (DWI) provides information about tissue maturation not seen on conventional magnetic resonance imaging. The aim of this study is to analyze the evolution over time of the apparent diffusion coefficient (ADC) of normal fetal brain in utero. DWI was performed on 78 fetuses, ranging from 23 to 37 gestational weeks (GW). All children showed at follow-up a normal neurological evaluation. ADC values were obtained in the deep white matter (DWM) of the centrum semiovale, the frontal, parietal, occipital and temporal lobe, in the cerebellar hemisphere, the brainstem, the basal ganglia (BG) and the thalamus. Mean ADC values in supratentorial DWM areas (1.68 {+-} 0.05 mm{sup 2}/s) were higher compared with the cerebellar hemisphere (1.25 {+-} 0.06 mm{sup 2}/s) and lowest in the pons (1.11 {+-} 0.05 mm{sup 2}/s). Thalamus and BG showed intermediate values (1.25 {+-} 0.04 mm{sup 2}/s). Brainstem, cerebellar hemisphere and thalamus showed a linear negative correlation with gestational age. Supratentorial areas revealed an increase in ADC values, followed by a decrease after the 30th GW. This study provides a normative data set that allows insights in the normal fetal brain maturation in utero, which has not yet been observed in previous studies on premature babies. (orig.)

  6. Diffusion-weighted imaging in characterization of cystic pancreatic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Sandrasegaran, K., E-mail: ksandras@iupui.edu [Department of Radiology, Indiana University School of Medicine, Indianapolis, IN (United States); Akisik, F.M.; Patel, A.A.; Rydberg, M. [Department of Radiology, Indiana University School of Medicine, Indianapolis, IN (United States); Cramer, H.M.; Agaram, N.P. [Department of Pathology, Indiana University School of Medicine, Indianapolis, IN (United States); Schmidt, C.M. [Department of Surgery, Indiana University School of Medicine, Indianapolis, IN (United States)

    2011-09-15

    Aim: To evaluate whether apparent diffusion coefficient (ADC) measurements from diffusion-weighted imaging (DWI) can characterize or predict the malignant potential of cystic pancreatic lesions. Materials and methods: Retrospective review of the magnetic resonance imaging (MRI) database over a 2-year period revealed 136 patients with cystic pancreatic lesions. Patients with DWI studies and histological confirmation of cystic mass were included. In patients with known pancreatitis, lesions with amylase content of >1000 IU/l that resolved on subsequent scans were included as pseudocysts. ADC of cystic lesions was measured by two independent reviewers. These values were then compared to categorize these lesions as benign or malignant using conventional MRI sequences. Results: Seventy lesions were analysed: adenocarcinoma (n = 4), intraductal papillary mucinous neoplasm (IPMN; n = 28), mucinous cystic neoplasm (MCN; n = 9), serous cystadenoma (n = 16), and pseudocysts (n = 13). There was no difference between ADC values of malignant and non-malignant lesions (p = 0.06), between mucinous and serous tumours (p = 0.12), or between IPMN and MCN (p = 0.42). ADC values for low-grade IPMN were significantly higher than those for high-grade or invasive IPMN (p = 0.03). Conclusion: ADC values may be helpful in deciding the malignant potential of IPMN. However, they are not useful in differentiating malignant from benign lesions or for characterizing cystic pancreatic lesions.

  7. Malignant versus benign mediastinal lesions: quantitative assessment with diffusion weighted MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Guemuestas, Sevtap; Inan, Nagihan; Sarisoy, Hasan Tahsin; Anik, Yonca; Arslan, Arzu; Ciftci, Ercuement; Akansel, Guer; Demirci, Ali [University of Kocaeli, Department of Radiology, School of Medicine, Umuttepe Kocaeli (Turkey)

    2011-11-15

    We aimed to evaluate the performance of diffusion-weighted magnetic resonance imaging in differentiating malignant from benign mediastinal lesions. Fifty-three mediastinal lesions were examined with T1- and T2-weighted (W) conventional images. Then, two diffusion-weighted images were obtained with b = 0 and 1000 s/mm{sup 2} values and apparent diffusion coefficients (ADC) were calculated. The statistical significance of differences between measurements was tested using the Student-t test. The mean ADC of malignant lesions was significantly lower than that of the benign masses (p < 0.001). The cut-off value of {<=} 1.39 x 10{sup -3} mm{sup 2}/s indicated a malignant lesion with a sensitivity of 95% and specificity of 87%. Diffusion-weighted imaging may be helpful in differentiating benign from malignant mediastinal masses. (orig.)

  8. Assessment of the residual tumour of colorectal liver metastases after chemotherapy: diffusion-weighted MR magnetic resonance imaging in the peripheral and entire tumour

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Mathilde; Doblas, Sabrina; Giraudeau, Celine [Paris Diderot University, INSERM, UMR 1149, Clichy (France); Ronot, Maxime; Van Beers, Bernard; Vilgrain, Valerie [Paris Diderot University, INSERM, UMR 1149, Clichy (France); Radiology Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hopitaux de Paris, APHP, Clichy (France); Belghiti, Jacques [Hepatobiliary Surgery Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hopitaux de Paris, APHP, Clichy (France); Paradis, Valerie [Pathology Department, Beaujon Hospital, University Hospitals Paris Nord Val de Seine, Assistance Publique-Hopitaux de Paris, APHP, Clichy (France)

    2016-01-15

    To evaluate the value of diffusion-weighted imaging (DWI) in detecting residual tumours (RTs) in colorectal liver metastases (CLMs) following chemotherapy, with a focus on tumour periphery. From January 2009-January 2012, 57 patients who underwent liver resection for CLMs with preoperative MRI (<3 months) including DWI were retrospectively included. CLMs were classified into three response groups on pathology: (1) major histological (MHR, RTs ≤ 10 %), (2) partial histological (PHR, RT = 10-49 %), and (3) no histological (NHR, RT ≥ 50 %). On DWI, regions of interest (ROIs) were drawn around the entire tumour and tumour periphery. Apparent diffusion (ADC) and pure diffusion (D) coefficients were calculated using a monoexponential fit, and compared using Kruskal-Wallis test on a lesion-per-lesion analysis. 111 CLMs were included. Fourteen (12.5 %), 42 (38 %) and 55 (49.5 %) CLMs presented a MHR, PHR and NHR, respectively. ADC and D of the peripheral ROIs were significantly higher in the MHR group (P = 0.013/P = 0.013). ADC and D from the entire tumour were not significantly different among the groups (P = 0.220/P = 0.103). In CLM treated with chemotherapy, ADC and D values from the entire tumour are not related to the degree of RT, while peripheral zone diffusion parameters could help identify metastases with MHR. (orig.)

  9. Whole Tumor Histogram-profiling of Diffusion-Weighted Magnetic Resonance Images Reflects Tumorbiological Features of Primary Central Nervous System Lymphoma.

    Science.gov (United States)

    Schob, Stefan; Münch, Benno; Dieckow, Julia; Quäschling, Ulf; Hoffmann, Karl-Titus; Richter, Cindy; Garnov, Nikita; Frydrychowicz, Clara; Krause, Matthias; Meyer, Hans-Jonas; Surov, Alexey

    2018-04-01

    Diffusion weighted imaging (DWI) quantifies motion of hydrogen nuclei in biological tissues and hereby has been used to assess the underlying tissue microarchitecture. Histogram-profiling of DWI provides more detailed information on diffusion characteristics of a lesion than the standardly calculated values of the apparent diffusion coefficient (ADC)-minimum, mean and maximum. Hence, the aim of our study was to investigate, which parameters of histogram-profiling of DWI in primary central nervous system lymphoma can be used to specifically predict features like cellular density, chromatin content and proliferative activity. Pre-treatment ADC maps of 21 PCNSL patients (8 female, 13 male, 28-89 years) from a 1.5T system were used for Matlab-based histogram profiling. Results of histopathology (H&E staining) and immunohistochemistry (Ki-67 expression) were quantified. Correlations between histogram-profiling parameters and neuropathologic examination were calculated using SPSS 23.0. The lower percentiles (p10 and p25) showed significant correlations with structural parameters of the neuropathologic examination (cellular density, chromatin content). The highest percentile, p90, correlated significantly with Ki-67 expression, resembling proliferative activity. Kurtosis of the ADC histogram correlated significantly with cellular density. Histogram-profiling of DWI in PCNSL provides a comprehensible set of parameters, which reflect distinct tumor-architectural and tumor-biological features, and hence, are promising biomarkers for treatment response and prognosis. Copyright © 2018. Published by Elsevier Inc.

  10. Characterization of Soft Tissue Tumors by Diffusion-Weighted Imaging

    International Nuclear Information System (INIS)

    Pekcevik, Yeliz; Kahya, Mehmet Onur; Kaya, Ahmet

    2015-01-01

    Diffusion-weighted imaging (DWI) is a noninvasive method for investigation of tumor histological content. It has been applied for some musculoskeletal tumors and reported to be useful. The aim of the present study was to prospectively evaluate the apparent diffusion coefficient (ADC) values of benign and malignant soft tissue tumors and to determine if ADC can help differentiate these tumors. DWI was performed on 25 histologically proven soft tissue masses. It was obtained with a single-shot echo-planar imaging technique using a 1.5T magnetic resonance (MR) machine. The mean ADC values were calculated. We grouped soft tissue tumors as benign cystic, benign solid or mixed, malignant cystic and malignant solid or mixed tumors and compared mean ADC values between these groups. There was only one patient with a malignant cystic tumor and was not included in the statistical analysis. The median ADC values of benign and malignant tumors were 2.31 ± 1.29 and 0.90 ± 0.70 (median ± interquartile range), respectively. The mean ADC values were different between benign and malignant tumors (P = 0.031). Benign cystic tumors had significantly higher ADC values than benign solid or mixed tumors and malignant solid or mixed tumors (p values were < 0.001 and 0.003, respectively). Malignant solid or mixed tumors had lower ADC values than benign solid or mixed tumors (P = 0.02). Our preliminary results have shown that although there is some overlap between benign and malignant tumors, adding DWI, MR imaging to routine soft tissue tumor protocols may improve diagnostic accuracy

  11. Predictive value of diffusion-weighted imaging without and with including contrast-enhanced magnetic resonance imaging in image analysis of head and neck squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Noij, Daniel P., E-mail: d.noij@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Pouwels, Petra J.W., E-mail: pjw.pouwels@vumc.nl [Department of Physics and Medical Technology, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Ljumanovic, Redina, E-mail: rljumanovic@adventh.org [Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Knol, Dirk L., E-mail: dirklknol@gmail.com [Department of Epidemiology and Biostatistics, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Doornaert, Patricia, E-mail: p.doornaert@vumc.nl [Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Bree, Remco de, E-mail: r.debree@vumc.nl [Department of Otolaryngology – Head and Neck Surgery, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Castelijns, Jonas A., E-mail: j.castelijns@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands); Graaf, Pim de, E-mail: p.degraaf@vumc.nl [Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, Amsterdam, Noord-Holland (Netherlands)

    2015-01-15

    Highlights: • Primary tumor volume and lymph node ADC1000 are predictors of survival. • CE-T1WI does not improve the prognostic capacity of DWI. • Using CE-T1WI for ROI placement results in lower interobserver agreement. - Abstract: Objectives: To assess disease-free survival (DFS) in head and neck squamous cell carcinoma (HNSCC) treated with (chemo)radiotherapy ([C]RT). Methods: Pretreatment MR-images of 78 patients were retrospectively studied. Apparent diffusion coefficients (ADC) were calculated with two sets of two b-values: 0–750 s/mm{sup 2} (ADC{sub 750}) and 0–1000 s/mm{sup 2} (ADC{sub 1000}). One observer assessed tumor volume on T1-WI. Two independent observers assessed ADC-values of primary tumor and largest lymph node in two sessions (i.e. without and with including CE-T1WI in image analysis). Interobserver and intersession agreement were assessed with intraclass correlation coefficients (ICC) separately for ADC{sub 750} and ADC{sub 1000}. Lesion volumes and ADC-values were related to DFS using Cox regression analysis. Results: Median follow-up was 18 months. Interobserver ICC was better without than with CE-T1WI (primary tumor: 0.92 and 0.75–0.83, respectively; lymph node: 0.81–0.83 and 0.61–0.64, respectively). Intersession ICC ranged from 0.84 to 0.89. With CE-T1WI, mean ADC-values of primary tumor and lymph node were higher at both b-values than without CE-T1WI (P < 0.001). Tumor volume (sensitivity: 73%; specificity: 57%) and lymph node ADC{sub 1000} (sensitivity: 71–79%; specificity: 77–79%) were independent significant predictors of DFS without and with including CE-T1WI (P < 0.05). Conclusions: Pretreatment primary tumor volume and lymph node ADC{sub 1000} were significant independent predictors of DFS in HNSCC treated with (C)RT. DFS could be predicted from ADC-values acquired without and with including CE-T1WI in image analysis. The inclusion of CE-T1WI did not result in significant improvements in the predictive value of

  12. Diffusion-weighted MR imaging findings in carbon monoxide poisoning

    International Nuclear Information System (INIS)

    Teksam, M.; Casey, S.O.; Michel, E.; Liu, H.; Truwit, C.L.

    2002-01-01

    Diffusion-weighted MR imaging (DWI) of two patients with carbon monoxide (CO) poisoning demonstrated white matter and cortical hyperintensities. In one patient, the changes on the FLAIR sequence were more subtle than those on DWI. The DWI abnormality in this patient represented true restriction. In the second patient, repeated exposure to CO caused restricted diffusion. DWI may be helpful for earlier identification of the changes of acute CO poisoning. (orig.)

  13. Dynamic Contrast Magnetic Resonance Imaging (DCE-MRI) and Diffusion Weighted MR Imaging (DWI) for Differentiation between Benign and Malignant Salivary Gland Tumors

    Science.gov (United States)

    Assili, S.; Fathi Kazerooni, A.; Aghaghazvini, L.; Saligheh Rad, H.R.; Pirayesh Islamian, J.

    2015-01-01

    Background Salivary gland tumors form nearly 3% of head and neck tumors. Due to their large histological variety and vicinity to facial nerves, pre-operative diagnosis and differentiation of benign and malignant parotid tumors are a major challenge for radiologists. Objective The majority of these tumors are benign; however, sometimes they tend to transform into a malignant form. Functional MRI techniques, namely dynamic contrast enhanced (DCE-) MRI and diffusion-weighted MRI (DWI) can indicate the characteristics of tumor tissue. Methods DCE-MRI analysis is based on the parameters of time intensity curve (TIC) before and after contrast agent injection. This method has the potential to identify the angiogenesis of tumors. DWI analysis is performed according to diffusion of water molecules in a tissue for determination of the cellularity of tumors. Conclusion According to the literature, these methods cannot be used individually to differentiate benign from malignant salivary gland tumors. An effective approach could be to combine the aforementioned methods to increase the accuracy of discrimination between different tumor types. The main objective of this study is to explore the application of DCE-MRI and DWI for assessment of salivary gland tumor types. PMID:26688794

  14. Dynamic Contrast Magnetic Resonance Imaging (DCE-MRI and Diffusion Weighted MR Imaging (DWI for Differentiation between Benign and Malignant Salivary Gland Tumors

    Directory of Open Access Journals (Sweden)

    Assili S

    2012-12-01

    Full Text Available Background: Salivary gland tumors form nearly 3% of head and neck tumors. Due to their large histological variety and vicinity to facial nerves, pre-operative diagnosis and differentiation of benign and malignant parotid tumors are a major challenge for radiologists. Objective: The majority of these tumors are benign; however, sometimes they tend to transform into a malignant form. Functional MRI techniques, namely dynamic contrast enhanced (DCE- MRI and diffusion-weighted MRI (DWI can indicate the characteristics of tumor tissue. Methods: DCE-MRI analysis is based on the parameters of time intensity curve (TIC before and after contrast agent injection. This method has the potential to identify the angiogenesis of tumors. DWI analysis is performed according to diffusion of water molecules in a tissue for determination of the cellularity of tumors. Conclusion: According to the literature, these methods cannot be used individually to differentiate benign from malignant salivary gland tumors. An effective approach could be to combine the aforementioned methods to increase the accuracy of discrimination between different tumor types. The main objective of this study is to explore the application of DCE-MRI and DWI for assessment of salivary gland tumor types.

  15. Dynamic Contrast Magnetic Resonance Imaging (DCE-MRI) and Diffusion Weighted MR Imaging (DWI) for Differentiation between Benign and Malignant Salivary Gland Tumors.

    Science.gov (United States)

    Assili, S; Fathi Kazerooni, A; Aghaghazvini, L; Saligheh Rad, H R; Pirayesh Islamian, J

    2015-12-01

    Salivary gland tumors form nearly 3% of head and neck tumors. Due to their large histological variety and vicinity to facial nerves, pre-operative diagnosis and differentiation of benign and malignant parotid tumors are a major challenge for radiologists. The majority of these tumors are benign; however, sometimes they tend to transform into a malignant form. Functional MRI techniques, namely dynamic contrast enhanced (DCE-) MRI and diffusion-weighted MRI (DWI) can indicate the characteristics of tumor tissue. DCE-MRI analysis is based on the parameters of time intensity curve (TIC) before and after contrast agent injection. This method has the potential to identify the angiogenesis of tumors. DWI analysis is performed according to diffusion of water molecules in a tissue for determination of the cellularity of tumors. According to the literature, these methods cannot be used individually to differentiate benign from malignant salivary gland tumors. An effective approach could be to combine the aforementioned methods to increase the accuracy of discrimination between different tumor types. The main objective of this study is to explore the application of DCE-MRI and DWI for assessment of salivary gland tumor types.

  16. Diffusion-weighted magnetic resonance imaging for the initial characterization of non-fatty soft tissue tumors: correlation between T2 signal intensity and ADC values

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto [Service d' Imagerie Guilloz, CHU Nancy, Nancy (France); Universite de Lorraine, IADI, UMR S 947, Vandoeuvre-les-Nancy (France); Gay, Frederique; Blum, Alain [Service d' Imagerie Guilloz, CHU Nancy, Nancy (France); Chen, Bailiang; Felblinger, Jacques [Universite de Lorraine, IADI, UMR S 947, Vandoeuvre-les-Nancy (France); Zins, Marie [University Versailles St-Quentin, Versailles (France); Inserm, Centre for research in Epidemiology and Population Health (CESP), U1018, Villejuif (France); Sirveaux, Francois [Centre Chirurgical Emile Galle, Service de Chirurgie Traumatologique et Orthopedique, Nancy (France)

    2016-02-15

    To evaluate the performance of quantitative diffusion-weighted imaging (DWI) correlated with T2 signal in differentiating non-fatty benign from malignant tumors. A total of 76 patients with a histologically confirmed non-fatty soft tissue tumors (46 benign and 30 malignant) were prospectively included in this ethics committee approved study. All patients signed an informed consent and underwent MRI with DWI with two b values (0 and 600). ADC values from the solid components of these tumors were obtained and were correlated with the lesion's signal intensity on T2-weighted fat-saturated sequences. ADC values were obtained from adjacent normal muscle to allow calculation of tumor/muscle ADC ratios. There were 58 hyperintense and 18 iso or hypointense lesions. All hypointense lesions were benign. The mean ADC values for benign and malignant tumors were 1.47 ± 0.54 x 10{sup -3} and 1.17 ± 0.38 x 10{sup -3} mm{sup 2}/s respectively (p < 0.005). The mean ADC ratio in benign iso or hypointense tumors was significantly lower than that of hyperintense ones (0.76 ± 0.21 versus 1.58 ± 0.82 - p < 0.0001). An ADC ratio lower than 0.915 was highly specific for malignancy (96.4 %), whereas an ADC ratio higher than 1.32 was highly sensitive for benign lesions (90 %). ADC analysis can be useful in the initial characterization of T2 hyperintense non-fatty soft tissue masses, although this technique alone is not likely to change patient management. (orig.)

  17. Determination of malignancy and characterization of hepatic tumor type with diffusion-weighted magnetic resonance imaging: comparison of apparent diffusion coefficient and intravoxel incoherent motion-derived measurements.

    Science.gov (United States)

    Doblas, Sabrina; Wagner, Mathilde; Leitao, Helena S; Daire, Jean-Luc; Sinkus, Ralph; Vilgrain, Valérie; Van Beers, Bernard E

    2013-10-01

    The objective of this study was to compare the value of the apparent diffusion coefficient (ADC) determined with 3 b values and the intravoxel incoherent motion (IVIM)-derived parameters in the determination of malignancy and characterization of hepatic tumor type. Seventy-six patients with 86 solid hepatic lesions, including 8 hemangiomas, 20 lesions of focal nodular hyperplasia, 9 adenomas, 30 hepatocellular carcinomas, 13 metastases, and 6 cholangiocarcinomas, were assessed in this prospective study. Diffusion-weighted images were acquired with 11 b values to measure the ADCs (with b = 0, 150, and 500 s/mm) and the IVIM-derived parameters, namely, the pure diffusion coefficient and the perfusion-related diffusion fraction and coefficient. The diffusion parameters were compared between benign and malignant tumors and between tumor types, and their diagnostic value in identifying tumor malignancy was assessed. The apparent and pure diffusion coefficients were significantly higher in benign than in malignant tumors (benign: 2.32 [0.87] × 10 mm/s and 1.42 [0.37] × 10 mm/s vs malignant: 1.64 [0.51] × 10 mm/s and 1.14 [0.28] × 10 mm/s, respectively; P coefficients provided similar accuracy in assessing tumor malignancy (areas under the receiver operating characteristic curve of 0.770 and 0.723, respectively). In the multigroup analysis, the ADC was found to be significantly higher in hemangiomas than in hepatocellular carcinomas, metastases, and cholangiocarcinomas. In the same manner, it was higher in lesions of focal nodular hyperplasia than in metastases and cholangiocarcinomas. However, the pure diffusion coefficient was significantly higher only in hemangiomas versus hepatocellular and cholangiocellular carcinomas. Compared with the ADC, the diffusion parameters derived from the IVIM model did not improve the determination of malignancy and characterization of hepatic tumor type.

  18. Diffusion-weighted imaging of the pancreas; Diffusionsbildgebung des Pankreas

    Energy Technology Data Exchange (ETDEWEB)

    Gruenberg, K. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie, E010, Heidelberg (Germany); Grenacher, L.; Klauss, M. [Universitaetsklinikum Heidelberg, Abt. Diagnostische und Interventionelle Radiologie, Heidelberg (Germany)

    2011-03-15

    Diffusion-weighted imaging (DWI) has increasingly gained in importance over the last 10 years especially in cancer imaging for differentiation of malignant and benign lesions. Through development of fast magnetic resonance imaging (MRI) sequences DWI is not only applicable in neuroradiology but also in abdominal imaging. As a diagnostic tool of the pancreas DWI enables a differentiation between normal tissue, cancer and chronic pancreatitis. The ADC values (apparent diffusion coefficient, the so-called effective diffusion coefficient) reported in the literature for healthy pancreatic tissue are in the range from 1.49 to 1.9 x 10{sup -3} mm{sup 2}/s, for pancreatic cancer in the range from 1.24 to 1.46 x 10{sup -3} mm{sup 2}/s and for autoimmune pancreatitis an average ADC value of 1.012 x 10{sup -3} mm{sup 2}/s. There are controversial data in the literature concerning the differentiation between chronic pancreatitis and pancreatic cancer. Using DWI-derived IVIM (intravoxel incoherent motion) the parameter f (perfusion fraction) seems to be advantageous but it is important to use several b values. In the literature the mean f value in chronic pancreatitis is around 16%, in pancreatic cancer 8% and in healthy pancreatic tissue around 25%. So far, DWI has not been helpful for differentiating cystic lesions of the pancreas. There are many references with other tumor entities and in animal models which indicate that there is a possible benefit of DWI in monitoring therapy of pancreatic cancer but so far no original work has been published. (orig.) [German] Die Diffusionsbildgebung (''diffusion-weighted imaging'', DWI) gewann in den letzten 10 Jahren insbesondere in der Tumorbildgebung zur Unterscheidung zwischen malignen und benignen Laesionen zunehmend an Bedeutung. Durch Entwicklung schnellerer MR-Sequenzen ist sie nicht nur in der Neuroradiologie, sondern auch in der Abdomenbildgebung einsetzbar. In der Pankreasdiagnostik ermoeglicht sie

  19. Intravoxel incoherent motion diffusion-weighted magnetic resonance imaging of focal vertebral bone marrow lesions: initial experience of the differentiation of nodular hyperplastic hematopoietic bone marrow from malignant lesions

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sunghoon; Kwack, Kyu-Sung; Kim, Jae Ho [Ajou University School of Medicine, Division of Musculoskeletal Radiology, Department of Radiology, Suwon, Gyeonggi-do (Korea, Republic of); Ajou University Medical Center, Musculoskeletal Imaging Laboratory, Suwon (Korea, Republic of); Chung, Nam-Su [Ajou University School of Medicine, Department of Orthopaedic Surgery, Suwon (Korea, Republic of); Hwang, Jinwoo [Philips Healthcare, Department of Clinical Science, Seoul (Korea, Republic of); Lee, Hyun Young [Ajou University Medical Center, Regional Clinical Trial Center, Suwon (Korea, Republic of); Yonsei University College of Medicine, Department of Biostatistics, Seoul (Korea, Republic of)

    2017-05-15

    To evaluate the ability of intravoxel incoherent motion (IVIM) diffusion-weighted magnetic resonance imaging (MRI) parameters to differentiate nodular hyperplastic hematopoietic bone marrow (HHBM) from malignant vertebral bone marrow lesions (VBMLs). A total of 33 patients with 58 VBMLs, including 9 nodular HHBM lesions, 39 bone metastases, and 10 myelomas, were retrospectively assessed. All diagnoses were confirmed either pathologically or via image assessment. IVIM diffusion-weighted MRI with 11 b values (from 0 to 800 s/mm{sup 2}) were obtained using a 3.0-T MR imager. The apparent diffusion coefficient (ADC), pure diffusion coefficient (D), perfusion fraction (f), and pseudodiffusion coefficient (D*) were calculated. ADC and IVIM parameters were compared using the Mann-Whitney U test. Receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic performances of ADC, D, f, and D* in terms of VBML characterization. The diagnostic performance of morphological MR sequences was also assessed for comparison. The ADC and D values of nodular HHBM were significantly lower than those of malignant VBML (both p values < 0.001), whereas the f value was significantly higher (p < 0.001). However, there were no significant differences in D* between the two groups (p = 0.688). On ROC analysis, the area under the curve (AUC) for D was 1.000, which was significantly larger than that for ADC (AUC = 0.902). Intravoxel incoherent motion diffusion-weighted MRI can be used to differentiate between nodular HHBM and malignant VBML. The D value was significantly lower for nodular HHBM, and afforded a better diagnostic performance than the ADC, f, and D* values in terms of such differentiation. (orig.)

  20. Diffusion-weighted MR imaging of ring-enhancing intracerebral lesions

    International Nuclear Information System (INIS)

    Li Youcheng; Li Jiance; Tian Wei; Li Zongfang

    2005-01-01

    Objective: To assess the diagnostic value of diffusion-weighted echo-planar MR Imaging (DWI) in ring-enhancing intracerebral lesions. Methods: Magnetic resonance diffusion-weighted images of ninty-three patients presenting with ring-ehancing intracerebral lesions diagnosed by clinical or histopathologic findings were studied retrospectively, including 21 gliomas, 26 metastases, 13 pyogenic abscesses, 18 neurocysticercoses and 15 subacute intracerebral hematomas. The signal intensity ratio on diffusion-weighted images and exponential diffusion coefficient images was calculated respectively in ring walls, central contents, and perilesional edemas of ring-enhancing lesions, and normal contralateral cerebral parenchyma was used for comparison. ADC values of interest of lesions, contralateral cerebral parenchyma and CFS were calculated as well. Results: In pyogenic abscesses and subacute intracerebral hematomas, the central content was always extremely hyperintense on diffusion-weighted images, and showed low ADCs [(0.56 ± 0.20) x 10 -3 mm 2 /s, (0.69 ± 0.16) x 10 -3 mm 2 /s, respectively]. On the other hand the central content of gliomas, metastases and neurocysticercoses was hypointense, and showed high ADCs [(2.76 ± 0.41 ) x 10 -3 mm 2 /s, (2.31 ± 0.39 ) x 10 -3 mm 2 /s, (2.10 ± 0.32) x 10 -3 mm 2 /s, respectively]. The ADCs of the first two lesions were significantly lower than of the last three lesions (P 2 -weighted images should be reviewed in daily clinical practice. (authors)

  1. Semiautomated spleen volumetry with diffusion-weighted MR imaging.

    Science.gov (United States)

    Lee, Jeongjin; Kim, Kyoung Won; Lee, Ho; Lee, So Jung; Choi, Sanghyun; Jeong, Woo Kyoung; Kye, Heewon; Song, Gi-Won; Hwang, Shin; Lee, Sung-Gyu

    2012-07-01

    In this article, we determined the relative accuracy of semiautomated spleen volumetry with diffusion-weighted (DW) MR images compared to standard manual volumetry with DW-MR or CT images. Semiautomated spleen volumetry using simple thresholding followed by 3D and 2D connected component analysis was performed with DW-MR images. Manual spleen volumetry was performed on DW-MR and CT images. In this study, 35 potential live liver donor candidates were included. Semiautomated volumetry results were highly correlated with manual volumetry results using DW-MR (r = 0.99; P volumetry was significantly shorter compared to that of manual volumetry with DW-MR (P volumetry with DW-MR images can be performed rapidly and accurately when compared with standard manual volumetry. Copyright © 2011 Wiley Periodicals, Inc.

  2. Aggressive Angiomyxoma with Diffusion-Weighted Magnetic Resonance Imaging and Dynamic Contrast Enhancement: A Case Report and Review of the Literature

    OpenAIRE

    S. Brunelle; F. Bertucci; B. Chetaille; B. Lelong; G. Piana; A. Sarran

    2013-01-01

    Introduction: Aggressive angiomyxoma (AA) is a rare benign soft tissue tumour usually affecting the pelvis and perineum of young women. Magnetic resonance imaging (MRI) is crucial in the management of AA patients for its diagnostic contribution and for the preoperative assessment of the actual tumour extension. Given the current development of less aggressive therapeutics associated with a higher risk of recurrence, close follow-up with MRI is fundamental after treatment. In this context, dif...

  3. Diffusion-weighted MR imaging of cystic lesions of neurocysticercosis: a preliminary study

    International Nuclear Information System (INIS)

    Raffin, Luciana S.; Bacheschi, Luiz A.; Machado, Luis R.; Nobrega, Jose P.S.; Coelho, Christina; Leite, Claudia C.

    2001-01-01

    Neurocysticercosis is an endemic disease in some developing countries. It has pleomorfic clinical and imaging findings, which are variable from patient to patient. In this preliminary note, we studied the magnetic resonance diffusion-weighted images of sixteen patients presenting with cystic lesions of this disease diagnosed by clinical and laboratorial findings. All the lesions had hypointense signal and the similar apparent diffusion coefficient values as the cerebrospinal fluid. (author)

  4. Monitoring early response to anti-angiogenic therapy: diffusion-weighted magnetic resonance imaging and volume measurements in colon carcinoma xenografts.

    Directory of Open Access Journals (Sweden)

    Moritz Jörg Schneider

    Full Text Available OBJECTIVES: To evaluate the use of diffusion-weighted MRI (DW-MRI and volume measurements for early monitoring of antiangiogenic therapy in an experimental tumor model. MATERIALS AND METHODS: 23 athymic nude rats, bearing human colon carcinoma xenografts (HT-29 were examined before and after 6 days of treatment with regorafenib (n = 12 or placebo (n = 11 in a clinical 3-Tesla MRI. For DW-MRI, a single-shot EPI sequence with 9 b-values (10-800 s/mm2 was used. The apparent diffusion coefficient (ADC was calculated voxelwise and its median value over a region of interest, covering the entire tumor, was defined as the tumor ADC. Tumor volume was determined using T2-weighted images. ADC and volume changes between first and second measurement were evaluated as classifiers by a receiver-operator-characteristic (ROC analysis individually and combined using Fisher's linear discriminant analysis (FLDA. RESULTS: All ADCs and volumes are stated as median±standard deviation. Tumor ADC increased significantly in the therapy group (0.76±0.09×10(-3 mm2/s to 0.90±0.12×10(-3 mm2/s; p<0.001, with significantly higher changes of tumor ADC than in the control group (0.10±0.11×10(-3 mm2/s vs. 0.03±0.09×10(-3 mm2/s; p = 0.027. Tumor volume increased significantly in both groups (therapy: 347.8±449.1 to 405.3±823.6 mm3; p = 0.034; control: 219.7±79.5 to 443.7±141.5 mm3; p<0.001, however, the therapy group showed significantly reduced tumor growth (33.30±47.30% vs. 96.43±31.66%; p<0.001. Area under the curve and accuracy of the ADC-based ROC analysis were 0.773 and 78.3%; and for the volume change 0.886 and 82.6%. The FLDA approach yielded an AUC of 0.985 and an accuracy of 95.7%. CONCLUSIONS: Regorafenib therapy significantly increased tumor ADC after 6 days of treatment and also significantly reduced tumor growth. However, ROC analyses using each parameter individually revealed a lack of accuracy in discriminating between therapy and

  5. Diffusion weighted imaging in cystic fibrosis disease: beyond morphological imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ciet, Pierluigi [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus Medical Center - Sophia Children' s Hospital, Department of Paediatrics, Respiratory Medicine and Allergology, P.O. Box 2060, Rotterdam, Zuid-Holland (Netherlands); Ca' Foncello - General Hospital, Department of Radiology, Treviso (Italy); Serra, Goffredo; Catalano, Carlo [University of Rome ' ' Sapienza' ' , Department of Radiology, Rome (Italy); Andrinopoulou, Eleni Rosalina [Erasmus Medical Center, Department of Biostatistics, Rotterdam (Netherlands); Bertolo, Silvia; Morana, Giovanni [Ca' Foncello - General Hospital, Department of Radiology, Treviso (Italy); Ros, Mirco [Ca' Foncello Hospital, Department of Pediatrics, Treviso (Italy); Colagrande, Stefano [University of Florence - Azienda Ospedaliero-Universitaria Careggi, Department of Experimental and Clinical Biomedical Sciences, Radiodiagnostic Unit n. 2, Florence (Italy); Tiddens, Harm A.W.M. [Erasmus Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus Medical Center - Sophia Children' s Hospital, Department of Paediatrics, Respiratory Medicine and Allergology, P.O. Box 2060, Rotterdam, Zuid-Holland (Netherlands)

    2016-11-15

    To explore the feasibility of diffusion-weighted imaging (DWI) to assess inflammatory lung changes in patients with Cystic Fibrosis (CF) CF patients referred for their annual check-up had spirometry, chest-CT and MRI on the same day. MRI was performed in a 1.5 T scanner with BLADE and EPI-DWI sequences (b = 0-600 s/mm{sup 2}). End-inspiratory and end-expiratory scans were acquired in multi-row scanners. DWI was scored with an established semi-quantitative scoring system. DWI score was correlated to CT sub-scores for bronchiectasis (CF-CT{sub BE}), mucus (CF-CT{sub mucus}), total score (CF-CT{sub total-score}), FEV{sub 1}, and BMI. T-test was used to assess differences between patients with and without DWI-hotspots. Thirty-three CF patients were enrolled (mean 21 years, range 6-51, 19 female). 4 % (SD 2.6, range 1.5-12.9) of total CF-CT alterations presented DWI-hotspots. DWI-hotspots coincided with mucus plugging (60 %), consolidation (30 %) and bronchiectasis (10 %). DWI{sub total-score} correlated (all p < 0.0001) positively to CF-CT{sub BE} (r = 0.757), CF-CT{sub mucus} (r = 0.759) and CF-CT{sub total-score} (r = 0.79); and negatively to FEV{sub 1} (r = 0.688). FEV{sub 1} was significantly higher (p < 0.0001) in patients without DWI-hotspots. DWI-hotspots strongly correlated with radiological and clinical parameters of lung disease severity. Future validation studies are needed to establish the exact nature of DWI-hotspots in CF patients. (orig.)

  6. Diffusion weighted imaging in cystic fibrosis disease: beyond morphological imaging

    International Nuclear Information System (INIS)

    Ciet, Pierluigi; Serra, Goffredo; Catalano, Carlo; Andrinopoulou, Eleni Rosalina; Bertolo, Silvia; Morana, Giovanni; Ros, Mirco; Colagrande, Stefano; Tiddens, Harm A.W.M.

    2016-01-01

    To explore the feasibility of diffusion-weighted imaging (DWI) to assess inflammatory lung changes in patients with Cystic Fibrosis (CF) CF patients referred for their annual check-up had spirometry, chest-CT and MRI on the same day. MRI was performed in a 1.5 T scanner with BLADE and EPI-DWI sequences (b = 0-600 s/mm 2 ). End-inspiratory and end-expiratory scans were acquired in multi-row scanners. DWI was scored with an established semi-quantitative scoring system. DWI score was correlated to CT sub-scores for bronchiectasis (CF-CT BE ), mucus (CF-CT mucus ), total score (CF-CT total-score ), FEV 1 , and BMI. T-test was used to assess differences between patients with and without DWI-hotspots. Thirty-three CF patients were enrolled (mean 21 years, range 6-51, 19 female). 4 % (SD 2.6, range 1.5-12.9) of total CF-CT alterations presented DWI-hotspots. DWI-hotspots coincided with mucus plugging (60 %), consolidation (30 %) and bronchiectasis (10 %). DWI total-score correlated (all p < 0.0001) positively to CF-CT BE (r = 0.757), CF-CT mucus (r = 0.759) and CF-CT total-score (r = 0.79); and negatively to FEV 1 (r = 0.688). FEV 1 was significantly higher (p < 0.0001) in patients without DWI-hotspots. DWI-hotspots strongly correlated with radiological and clinical parameters of lung disease severity. Future validation studies are needed to establish the exact nature of DWI-hotspots in CF patients. (orig.)

  7. Wallenberg's lateral medullary syndrome: diffusion-weighted imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Kitis, O.; Calli, C.; Yunten, N.; Kocaman, A.; Sirin, H. [Ege Univ., Izmir (Turkey). Dept. of Radiology

    2004-02-01

    To investigate the efficacy of diffusion-weighted imaging in patients with Wallenberg's lateral medullary syndrome. Thirteen patients with Wallenberg's lateral medullary syndrome were examined with conventional and echoplanar diffusion-weighted magnetic resonance (MR) imaging in a 1.5 T magnetic resonance unit. MR examinations were obtained in the acute or subacute stage of clinical syndrome, and diffusion-weighted imaging (DWI) was considered to be positive for infarction when an increase in signal was seen on b = 1000 s/mm2 images in the posterolateral medullary localization. DWIs were positive in 12 patients in the acute or subacute stages of this clinical syndrome. A false-negative result was obtained in only one patient examined within the first day, 10 h after onset of the symptoms. In the visual evaluation of the DWI, the contrast between normal and infarcted brainstem area was better in the high b-value images than in the apparent diffusion coefficient map images. DWI is a valuable technique for examining patients presenting with the signs and symptoms of Wallenberg's syndrome and high b-value images can provide complementary data to T2-weighted images. However, because most of our case group were in either the acute or subacute stage, true sensitivity of the method in the hyperacute stage of the syndrome remains unclear.

  8. Feasibility of 3.0 T diffusion-weighted nuclear magnetic resonance imaging in the evaluation of functional recovery of rats with complete spinal cord injury

    Directory of Open Access Journals (Sweden)

    Duo Zhang

    2015-01-01

    Full Text Available Diffusion tensor imaging is a sensitive way to reflect axonal necrosis and degeneration, glial cell regeneration and demyelination following spinal cord injury, and to display microstructure changes in the spinal cord in vivo. Diffusion tensor imaging technology is a sensitive method to diagnose spinal cord injury fiber tractography visualizes the white matter fibers, and directly displays the structural integrity and resultant damage of the fiber bundle. At present, diffusion tensor imaging is restricted to brain examinations, and is rarely applied in the evaluation of spinal cord injury. This study aimed to explore the fractional anisotropy and apparent diffusion coefficient of diffusion tensor magnetic resonance imaging and the feasibility of diffusion tensor tractography in the evaluation of complete spinal cord injury in rats. The results showed that the average combined scores were obviously decreased after spinal cord transection in rats, and then began to increase over time. The fractional anisotropy scores after spinal cord transection in rats were significantly lower than those in normal rats (P <0.05 the apparent diffusion coefficient was significantly increased compared with the normal group (P < 0.05. Following spinal cord transection, fractional anisotropy scores were negatively correlated with apparent diffusion coefficient values (r = -0.856, P < 0.01, and positively correlated with the average combined scores (r = 0.943, P < 0.01, while apparent diffusion coefficient values had a negative correlation with the average combined scores (r = -0.949, P < 0.01. Experimental findings suggest that, as a non-invasive examination, diffusion tensor magnetic resonance imaging can provide qualitative and quantitative information about spinal cord injury. The fractional anisotropy score and apparent diffusion coefficient have a good correlation with the average combined scores, which reflect functional recovery after spinal cord injury.

  9. Diffusion-weighted magnetic resonance imaging in metastatic gastrointestinal stromal tumor (GIST) - A pilot study on the assessment of treatment response in comparison with 18F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Sabine; Koehli, Melanie; Meuli, Reto [Dept. of Radiology, Centre Hospitalier Universitaire Vaudois, Univ. of Lausanne, Lausanne (Switzerland)], e-mail: sabine.schmidt@chuv.ch; Dunet, Vincent; Prior, John O. [Dept. of Nuclear Medicine, Centre Hospitalier Universitaire Vaudois, Uniausanne, Lausanne (Switzerland); Montemurro, Michael [Dept. of Oncology, Centre Hospitalier Universitaire Vaudois (CHUV), Univ. of Lausanne, Lausanne (Switzerland)

    2013-10-15

    Background: Diffusion-weighted magnetic resonance imaging (MRI) is increasingly being used for assessing the treatment success in oncology, but the real clinical value needs to evaluated by comparison with other, already established, metabolic imaging techniques. Purpose: To prospectively evaluate the clinical potential of diffusion-weighted MRI with apparent diffusion coefficient (ADC) mapping for gastrointestinal stromal tumor (GIST) response to targeted therapy compared with 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Material and Methods: Eight patients (mean age, 56{+-}11 years) known to have metastatic GIST underwent 18F-FDG PET/CT and MRI (T1Gd, DWI [b = 50,300,600], ADC mapping) simultaneously, before and after change in targeted therapy. MR and PET/CT examinations were first analyzed blindly. Second, PET/CT images were co-registered with T1Gd-MR images for lesion detection. Only 18F-FDG avid lesions were considered. Maximum standardized uptake value (SUV{sub max}) and the corresponding minimum ADC{sub min} were measured for the six largest lesions per patient, if any, on baseline and follow-up examinations. The relationship between changes in SUV{sub max} and ADCmin was analyzed (Spearman's correlation). Results: Twenty-four metastases (12 hepatic, 12 extra-hepatic) were compared on PET/CT and MR images. SUV{sub max} decreased from 7.7{+-}8.1 g/mL to 5.5{+-}5.4 g/mL (P = 0.20), while ADC{sub min} increased from 1.2{+-}0.3 X 10{sup -3}mm{sup 2}/s to 1.5{+-}0.3 X 10{sup -3}mm{sup 2}/s (P = 0.0002). There was a significant association between changes in SUV{sub max} and ADC{sub min} (rho = - 0.62, P = 0.0014), but not between changes in lesions size (P = 0.40). Conclusion: Changes in ADCmin correlated with the response of 18F-FDG avid GIST to targeted therapy. Thus, diffusion-weighted MRI may represent a radiation-free alternative for follow-up treatment for metastatic GIST patients.

  10. Diffusion-weighted imaging features in spinal cord infarction

    International Nuclear Information System (INIS)

    Zhang Jingsong; Huan Yi; Sun Lijun; Chang Yingjuan; Zhao Haitao; Yang Chunmin; Zhang Guangyun

    2005-01-01

    Objective: To analyze the diffusion-weighted MR imaging findings in ischemic spinal cord lesions and discuss the value of diffusion-weighted MR imaging in differentiating diagnosis with inflammatory diseases and tumors. Methods: Six patients (2 male, 4 female) with typical sudden onset of neurological deficits caused by spinal cord ischemia were evaluated. There were no definite etiologies in all patients. DW imaging was performed within 1 to 30 days after the initial neurological symptoms using a Philips Gyroscan 1.5 TMR system. Four patients had other scans including contrast-enhanced MR imaging (CE-MRI) and/or FLAIR scans. Two of them followed up with MR images in three months. All six patients were imaged using a multi-shot, navigator-corrected, echo-planar pulse sequence, and ADC values were calculated in sagittal-oriented plane. Results: MR abnormalities were demonstrated on sagittal T 2 -weighted images with 'patch-like' or 'strip-like' hyperintensities (6/6) and cord enlargement (5/6). Axial T 2 -weighted images showed bilateral (6/6) hyperintensities. In one patient only the posterior spinal artery (PSA) territory was involved. Spinal cord was mainly affected at the cervical (2/6) and thoracolumbar (4/6) region, two of them included the conus medullaris (T10-L1). DW images showed high signals in all infarct lesions, degree of intensity depended on scanning time from ill-onset and progress of illness and whether companied with hemorrhage. In this group, except one case with closely normal ADC value due to one month course of illness, the five others ADC values of lesions calculated from ADC maps arranged from 0.23 x 10 -3 mm 2 /s to 0.47 x 10 -3 mm 2 /s [average value (0.37 ± 0.10) x 10 -3 mm 2 /s], markedly lower than normal parts [ average value (0.89 ± 0.08) x 10 -3 mm 2 /s]. There were marked difference between lesions and normal regions (t=4.71, P 2 W images. Meanwhile, lesions could be displayed much better in DW images than in T 2 W images because

  11. Diffusion-weighted MR imaging findings in a patient with herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Heiner, L.; Demaerel, Ph.

    2003-01-01

    Introduction: Herpes simplex meningoencephalitis is one of the most common viral central nervous system infection in adults. Early diagnosis is essential for treatment. Case report: We present a case of a 68-year-old female patient with herpes simplex infection. On admission, she was in severe clinical condition. Diffusion-weighted (DW) magnetic resonance imaging detected brain involvement better than conventional sequences. After acyclovir therapy, the patient fully recovered. Conclusion: DW magnetic resonance imaging is expected to provide a more sensitive imaging in herpes simplex patients than conventional sequences

  12. Diffusion-weighted magnetic resonance imaging of extraocular muscles in patients with Grave's ophthalmopathy using turbo field echo with diffusion-sensitized driven-equilibrium preparation.

    Science.gov (United States)

    Hiwatashi, A; Togao, O; Yamashita, K; Kikuchi, K; Momosaka, D; Honda, H

    2018-03-20

    The purpose of this study was to correlate diffusivity of extraocular muscles, measured by three-dimensional turbo field echo (3DTFE) magnetic resonance (MR) imaging using diffusion-sensitized driven-equilibrium preparation, with their size and activity in patients with Grave's ophthalmopathy. Twenty-three patients with Grave's ophthalmopathy were included. There were 17 women and 6 men with a mean age of 55.8±12.6 (SD) years (range: 26-83 years). 3DTFE with diffusion-sensitized driven-equilibrium MR images were obtained with b-values of 0 and 500s/mm 2 . The apparent diffusion coefficient (ADC) of extraocular muscles was measured on coronal reformatted MR images. Signal intensities of extraocular muscles on conventional MR images were compared to those of normal-appearing white matter, and cross-sectional areas of the muscles were also measured. The clinical activity score was also evaluated. Statistical analyses were performed with Pearson correlation and Mann-Whitney U tests. On 3DTFE with diffusion-sensitized driven-equilibrium preparation, the mean ADC of the extraocular muscles was 2.23±0.37 (SD)×10 -3 mm2/s (range: 1.70×10 -3 -3.11×10 -3 mm 2 /s). There was a statistically significant moderate correlation between ADC and the size of the muscles (r=0.61). There were no statistically significant correlations between ADC and signal intensity on conventional MR and the clinical activity score. 3DTFE with diffusion-sensitized driven-equilibrium preparation technique allows quantifying diffusivity of extraocular muscles in patients with Grave's ophthalmopathy. The diffusivity of the extraocular muscles on 3DTFE with diffusion-sensitized driven-equilibrium preparation MR images moderately correlates with their size. Copyright © 2018. Published by Elsevier Masson SAS.

  13. Diffusion weighted MR imaging of transient ischemic attacks

    International Nuclear Information System (INIS)

    Chung, Jin Il; Kim, Dong Ik; Lee, Seung Ik; Yoon, Pyung Ho; Heo, Ji Hoe; Lee, Byung In

    2000-01-01

    To investigate the findings of diffusion-weighted MR imaging in patients with transient ischemic attacks (TIA). Between August 1996 and June 1999, 41 TIA patients (M:F =3D 28:13, mean age 57 (range, 27-75) years) with neurologic symptoms lasting less than 24 hours underwent diffusion-weighted MR imaging. The time interval between the onset of symptoms and MR examination was less than one week in 29 patients, from one week to one month in eight, and undetermined in four. Conventional MR and DWI were compared in terms of location of infarction and lesion size (less than 1 cm, 1-3 cm, greater than 3 cm), and we also determined the anatomical vascular territory of acute stroke lesions and possible etiologic mechanisms. The findings of DWI were normal in 24/41 patients (58.5%), while 15 (36.6%) showed acute ischemic lesions. The other two showed old lacunar infarcts. All acute and old DWI lesions were revealed by conventional MR imaging. Among the 15 acute stroke patients, seven had small vessel lacunar disease. In three patients, the infarction was less than 1 cm in size. Six patients showed large vessel infarction in the territory of the MCA, PCA, and PICA; the size of this was less than 1 cm in three patients, 1-3 cm in two, and more than 3 cm in one. In two patients, embolic infarction of cardiac origin in the territory of the MCA and AICA was diagnosed. The possible mechanism of TIA is still undetermined, but acute lesions revealed by DWI in TIA patients tend, in any case, to be small and multiple. (author)

  14. Diffusion-weighted MR imaging of thyroid nodules

    International Nuclear Information System (INIS)

    Bozgeyik, Zulkif; Coskun, Sonay; Ogur, Erkin; Dagli, A.F.; Ozkan, Yusuf; Sahpaz, Fatih

    2009-01-01

    The purpose of our study was to determine the diagnostic role of diffusion-weighted imaging (DWI) in the differentiating of malignant and benign thyroid nodules by using fine needle aspiration biopsy cytology criteria as a reference standard. The apparent diffusion coefficient (ADC) values of the normal-looking thyroid parenchyma were also evaluated both in normal patients and in patients with nodules. Between March 2007 and February 2008, 76 consecutive patients with ultrasound-diagnosed thyroid nodules and 20 healthy subjects underwent diffusion-weighted MR imaging by using single-shot spin echo, echo planar imaging. A total of 93 nodules were included in the study using the following b factors 100, 200, and 300 mm 2 /s. ADC values of thyroid nodules and normal area in all subjects were calculated and compared using suitable statistical analysis. Mean ADC values for malignant and benign nodules were 0.96±0.65 x 10 -3 and 3.06±0.71 x 10 -3 mm 2 /s. for b-300 factor, 0.56±0.43 x 10 -3 and 1.80±0.60 x 10 -3 mm 2 /s for b-200, and 0.30±0.20 x 10 -3 and 1.15±0.43 x 10 -3 mm 2 /s, for b-300, respectively. Mean ADC values of malignant nodules were lower than benign nodules. There were significant differences in ADC values between benign and malignant nodules. ADC values among normal-appearing thyroid parenchyma of patients and normal-appearing thyroid parenchyma of healthy subjects were insignificant at all b factors. Benign nodules have higher ADC values than malignant ones. DWI may be helpful in differentiating malign and benign thyroid nodules. (orig.)

  15. Extended diffusion weighted magnetic resonance imaging with two-compartment and anomalous diffusion models for differentiation of low-grade and high-grade brain tumors in pediatric patients

    Energy Technology Data Exchange (ETDEWEB)

    Burrowes, Delilah; Deng, Jie [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Northwestern University, Feinberg School of Medicine, Department of Radiology, Chicago, IL (United States); Fangusaro, Jason R. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Hematology/Oncology, Chicago, IL (United States); Northwestern University, Feinberg School of Medicine, Department of Pediatrics-Hematology, Oncology, and Stem Cell Transplantation, Chicago, IL (United States); Nelson, Paige C.; Rozenfeld, Michael J. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Zhang, Bin [Cincinnati Children' s Hospital Medical Center, Department of Biostatistics and Epidemiology, Cincinnati, OH (United States); Wadhwani, Nitin R. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Pathology and Laboratory Medicine, Chicago, IL (United States); Northwestern University, Feinberg School of Medicine, Department of Pathology, Chicago, IL (United States)

    2017-08-15

    The purpose of this study was to examine advanced diffusion-weighted magnetic resonance imaging (DW-MRI) models for differentiation of low- and high-grade tumors in the diagnosis of pediatric brain neoplasms. Sixty-two pediatric patients with various types and grades of brain tumors were evaluated in a retrospective study. Tumor type and grade were classified using the World Health Organization classification (WHO I-IV) and confirmed by pathological analysis. Patients underwent DW-MRI before treatment. Diffusion-weighted images with 16 b-values (0-3500 s/mm{sup 2}) were acquired. Averaged signal intensity decay within solid tumor regions was fitted using two-compartment and anomalous diffusion models. Intracellular and extracellular diffusion coefficients (D{sub slow} and D{sub fast}), fractional volumes (V{sub slow} and V{sub fast}), generalized diffusion coefficient (D), spatial constant (μ), heterogeneity index (β), and a diffusion index (index{sub d}iff = μ x V{sub slow}/β) were calculated. Multivariate logistic regression models with stepwise model selection algorithm and receiver operating characteristic (ROC) analyses were performed to evaluate the ability of each diffusion parameter to distinguish tumor grade. Among all parameter combinations, D and index{sub d}iff jointly provided the best predictor for tumor grades, where lower D (p = 0.03) and higher index{sub d}iff (p = 0.009) were significantly associated with higher tumor grades. In ROC analyses of differentiating low-grade (I-II) and high-grade (III-IV) tumors, index{sub d}iff provided the highest specificity of 0.97 and D provided the highest sensitivity of 0.96. Multi-parametric diffusion measurements using two-compartment and anomalous diffusion models were found to be significant discriminants of tumor grading in pediatric brain neoplasms. (orig.)

  16. Diffusion weighted imaging with circularly polarized oscillating gradients

    DEFF Research Database (Denmark)

    Lundell, Henrik; Sønderby, Casper Kaae; Dyrby, Tim B

    2015-01-01

    presented. One major hurdle in practical implementation is the low effective diffusion weighting provided at high frequency with limited gradient strength. THEORY: As a solution to the low diffusion weighting of OGSE, circularly polarized OGSE (CP-OGSE) is introduced. CP-OGSE gives a twofold increase...

  17. Incidence of ischemic lesions by diffusion-weighted imaging after carotid endarterectomy with routine shunt usage

    International Nuclear Information System (INIS)

    Inoue, Tomohiro; Tsutsumi, Kazuo; Adachi, Shinobu; Tanaka, Shota; Yako, Kyoko; Saito, Kuniaki; Kunii, Naoto; Maeda, Keiitirou

    2006-01-01

    Temporary intraluminal shunt was used during 72 consecutive carotid endarterectomies (CEAs) in 61 patients (bilateral CEA in 11 patients) during October 2001 and September 2005. The medical records of these patients were retrospectively reviewed. All procedures were performed with routine shunt insertion without monitoring such as electroencephalography. Pre- and postoperative diffusion-weighted magnetic resonance (MR) imaging was used to detect ischemic complications. Postoperative angiography was performed in 70 cases to detect abnormalities such as major stenosis or dissection of the distal end. Symptomatic ischemic complication occurred in one patient at 1 month. Postoperative diffusion-weighted MR imaging detected new hyperintense lesions in three patients including the symptomatic patient. Postoperative angiography confirmed that the distal end was satisfactory in all cases. The incidence of ischemic lesions of embolic origin after CEA with routine shunt usage is acceptably low if the procedure of shunt device insertion and removal is meticulously conducted. (author)

  18. Familial Mediterranean fever mimicking septic arthritis: distinguishing with diffusion weighted imaging

    International Nuclear Information System (INIS)

    Oner, Ali Yusuf; Ucar, Murat; Akpek, Sergin; Tokgoz, Nil

    2007-01-01

    FMF arthritis is generally monoarticular in origin. The affected joint is hot, tender, red and mimics septic arthritis. Conventional imaging findings, including magnetic resonance imaging (MRI) and ultrasound, do not help differentiate between these two entities. The final diagnosis depends on culture of the synovial fluid, and therefore initiation of proper drug therapy can be delayed. Diffusion weighted imaging (DWI), with its ability to detect altered water-proton mobility, might play an important role as a fast and non-invasive problem-solving tool in this setting. We here present MRI and DWI findings of a case of FMF arthritis mimicking septic arthritis. (orig.)

  19. Diffusion weighted MR imaging of brachial plexus diseases

    International Nuclear Information System (INIS)

    Okinaga, Shuji; Korenaga, Tateo; Tekemura, Atsushi; Tajiri, Yasuhito; Kawano, Ken-Ichi

    2010-01-01

    Diffusion weighted image (DWI) can specifically give running of nerve fibers as they have diffusion anisotropic property and DW whole body imaging with background body signal suppression (DWIBS) procedure, which being capable of imaging cervical and lumber nerve roots, is thus suggested to be useful for diagnosis of diseases related to brachial plexus (BP). The purpose of the present study is to confirm the usefulness of DWIBS by comparison of its images of the normal and sick plexuses. Subjects are 5 normal healthy males (27-36 y), 29 patients (19 M/10 F, 7-73 y) with BP diseases (10 cases of external injury, 6 of obstetric palsy, 2 of paralysis by dysfunctional position, 6 by Schwannoma, 2 by metastasis of breast cancer and 3 by radiation) and, to see the diagnostic specificity, 9 patients (M 7/F 2, 15-64 y) with severely reduced hand force by nervous causes other than BP ones. MRI with Philips Gyroscan INTERA 1.5T machine is conducted for DWIBS by DWI with single shot EPI (echo planar imaging) with the coil of either sensitivity encoding (SENSE) Cardiac, Flex-M or -S. Images are reconstructed 3D by a radiological technician possessing no information concerning patient's conditions, with Philips software Soap-bubble tool on the workstation, and are then evaluated by a radiologist and an orthopedist separately. It is found that BP disorders by injury, obstetric palsy and tumors, of which diagnosis has been difficult hitherto, can be imaged either negatively or positively depending on their history. In radiation paralysis, only 1/3 cases give a reduced signal intensity in the whole BP. DWIBS will be a new diagnostic mean for systemic peripheral nerve diseases as well as BP ones. (T.T.)

  20. Diffusion-weighted imaging in acute bacterial meningitis in infancy

    International Nuclear Information System (INIS)

    Jan, W.; Zimmerman, R.A.; Bilaniuk, L.T.; Hunter, J.V.; Simon, E.M.; Haselgrove, J.

    2003-01-01

    Bacterial meningitis is frequently fatal or leads to severe neurological impairment. Complications such as vasculitis, resulting in infarcts, should be anticipated and dealt with promptly. Our aim was to demonstrate the complications of meningitis by diffusion weighted imaging (DWI) in patients who deteriorated despite therapy. We studied 13 infants between the ages of 1 day and 32 months who presented with symptoms ranging from fever and vomiting to seizures, encephalopathy and coma due to bacterial meningitis, performing MRI, including DWI, 2-5 days after presentation. Multiple infarcts were found on DWI in 12 of the 13, most commonly in the frontal lobes (in 10). Global involvement was seen in four children, three of whom died; the fourth had a very poor outcome. In one case abnormalities on DWI were due to subdural empyemas. We diagnosed vasculitis in three of five patients studied with MRA. We think DWI an important part of an MRI study in infants with meningitis. Small cortical or deep white-matter infarcts due to septic vasculitis can lead to tissue damage not easily recognized on routine imaging and DWI can be used to confirm that extra-axial collections represent empyemas. (orig.)

  1. Diffusion-weighted imaging in acute bacterial meningitis in infancy

    Energy Technology Data Exchange (ETDEWEB)

    Jan, W.; Zimmerman, R.A.; Bilaniuk, L.T.; Hunter, J.V.; Simon, E.M.; Haselgrove, J. [Department of Radiology, Children' s Hospital of Philadelphia, 34th Street and Civic Center Boulevard, PA 19104, Philadelphia (United States)

    2003-09-01

    Bacterial meningitis is frequently fatal or leads to severe neurological impairment. Complications such as vasculitis, resulting in infarcts, should be anticipated and dealt with promptly. Our aim was to demonstrate the complications of meningitis by diffusion weighted imaging (DWI) in patients who deteriorated despite therapy. We studied 13 infants between the ages of 1 day and 32 months who presented with symptoms ranging from fever and vomiting to seizures, encephalopathy and coma due to bacterial meningitis, performing MRI, including DWI, 2-5 days after presentation. Multiple infarcts were found on DWI in 12 of the 13, most commonly in the frontal lobes (in 10). Global involvement was seen in four children, three of whom died; the fourth had a very poor outcome. In one case abnormalities on DWI were due to subdural empyemas. We diagnosed vasculitis in three of five patients studied with MRA. We think DWI an important part of an MRI study in infants with meningitis. Small cortical or deep white-matter infarcts due to septic vasculitis can lead to tissue damage not easily recognized on routine imaging and DWI can be used to confirm that extra-axial collections represent empyemas. (orig.)

  2. Diffusion-weighted MR imaging of transplanted kidneys: Preliminary report.

    Science.gov (United States)

    Wypych-Klunder, Katarzyna; Adamowicz, Andrzej; Lemanowicz, Adam; Szczęsny, Wojciech; Włodarczyk, Zbigniew; Serafin, Zbigniew

    2014-01-01

    An aim of this study was to assess the feasibility of DWI in the early period after kidney transplantation. We also aimed to compare ADC and eADC values in the cortex and medulla of the kidney, to estimate image noise and variability of measurements, and to verify possible relation between selected labolatory results and diffusion parameters in the transplanted kidney. Examinations were performed using a 1.5 T MR unit. DWI (SE/EPI) was performed in the axial plane using b-values of 600 and 1000. ADC and eADC measurements were performed in four regions of interest within the renal cortex and in three regions within the medulla. Relative variability of results and signal-to-noise ratio (SNR) were calculated. The analysis included 15 patients (mean age 52 years). The mean variability of ADC was significantly lower than that of eADC (6.8% vs. 10.8%, respectively; p30 ml/min./1.73 m(2) (p<0.05). Diffusion-weighted imaging of transplanted kidneys is technically challenging, especially in patients in the early period after transplantation. From a technical point of view, the best quality parameters offer quality ADC measurement in the renal cortex using b1000. ADC and eADC values in the renal cortex measured at b1000 present a relationship with eGFR.

  3. Diffusion-weighted imaging of the musculoskeletal system in humans

    International Nuclear Information System (INIS)

    Baur, A.; Reiser, M.F.

    2000-01-01

    This article reviews the principles of diffusion-weighted imaging (DWI) and recent results in DWI of the musculoskeletal system. The potential of DWI in the diagnosis of pathology of the musculoskeletal system is discussed. DWI is a relatively new MR imaging technique that has already been established in neuroradiology, especially in the early detection of brain ischemia. The random motion of water protons on a molecular basis can be measured with DWI. To date DWI of the abdomen and of the musculoskeletal system has only been employed in scientific studies, but first results indicate that it may also be beneficial in these fields. Different diffusion characteristics have been found in normal tissues such as muscle, fat and bone marrow. Also, pathologic entities such as neoplasms, post-therapeutic soft tissue changes and inflammatory processes can be differentiated. Normal muscle shows significantly higher diffusion values than subcutaneous fat and bone marrow, due to a higher mobility of water protons within muscle. Soft tissue tumors exhibit a significantly lower diffusion value compared with post-therapeutic soft tissue changes and inflammatory processes. Necrotic tumor tissue can be distinguished from viable tumor due to significantly higher diffusion of water protons within necrotic tissue. (orig.)

  4. Diffusion weighted imaging of female pelvic cancers: Concepts and clinical applications

    International Nuclear Information System (INIS)

    Punwani, Shonit

    2011-01-01

    Early applications of diffusion weighted magnetic resonance imaging (DWI) were limited to neuroimaging, concentrating either on stroke or brain tumours. With recent advances in MRI hardware and software DWI is now increasingly being investigated for cancer assessment throughout the body. Clinical applications of DWI relating to female pelvic cancers have largely concentrated on detection, localisation and staging of disease. More recently investigators have started to evaluate the ability of DWI for determining tumour histology and even predicting the outcome of chemoradiation treatment. This article reviews the physical concepts of MR diffusion weighting, illustrates the biophysical basis of diffusion contrast and reports the clinical applications of DWI for cervical, endometrial, ovarian, rectal and bladder tumours.

  5. Diffusion Weighted Imaging in Acute Attacks of Multiple Sclerosis

    International Nuclear Information System (INIS)

    Davoudi, Yasmin; Foroughipour, Mohsen; Torabi, Reza; Layegh, Parvaneh; Matin, Nassim; Shoeibi, Ali

    2016-01-01

    Multiple sclerosis (MS) is one of the most common autoimmune disorders of the central nervous system. In spite of various imaging modalities, the definitive diagnosis of MS remains challenging. This study was designed to evaluate the usefulness of diffusion weighted imaging (DWI) in the diagnosis of acute MS attack and to compare its results with contrast enhanced MRI (CE-MRI). In this cross sectional study, seventy patients with definite diagnosis of relapsing-remitting MS were included. CE-MRI using 0.1 mmol/kg gadolinium as well as DWI sequences were performed for all patients. The percentage of patients with positive DWI was compared with the results of CE-MRI and the consistency between the two imaging modalities was evaluated. Moreover, the relationship between the time of onset of patient’s symptoms and test results for both methods were investigated. CE-MRI yielded positive results for 61 (87%) patients and DWI yielded positive for 53 (76%) patients. In fifty patients (71.42%), both tests were positive and in six cases (8.57%), both were negative. The test results of three patients turned out to be positive in DWI, while they tested negative in CE-MRI. There was no significant relationship between the results of CE-MRI as well as DWI and the time of imaging from the onset of symptoms. These data indicate that while CE-MRI will depict more positive results, there are cases in which DWI will show a positive result while CE-MRI is negative. We suggest that the combination of these two imaging modalities might yield more positive results in diagnosing acute MS attack giving rise to a more accurate diagnosis

  6. [Diagnostic efficiency of decline rate of signal intensity and apparent diffusion coefficient with different b values for differentiating benign and malignant breast lesions on diffusion-weighted 3.0T magnetic resonance imaging].

    Science.gov (United States)

    Jiang, Jing; Liu, Wanhua; Ye, Yuanyuan; Wang, Rui; Li, Fengfang; Peng, Chengyu

    2014-06-17

    To investigate the diagnostic efficiency of decline rate of signal intensity and apparent diffusion coefficient with different b values for differentiating benign and malignant breast lesions on diffusion-weighted 3.0 T magnetic resonance imaging. A total of 152 patients with 162 confirmed histopathologically breast lesions (85 malignant and 77 benign) underwent 3.0 T diffusion-weighted magnetic resonance imaging. Four b values (0, 400, 800 and 1 000 s/mm²) were used. The signal intensity and ADC values of breast lesions were measured respectively. The signal intensity decline rate (SIDR) and apparent diffusion coefficient decline rate (ADCDR) were calculated respectively. SIDR = (signal intensity of lesions with low b value-signal intensity of lesions with high b value)/signal intensity of lesions with low b value, ADCDR = (ADC value of lesions with low b value-ADC value of lesions with high b value) /ADC value of lesions with low b value. The independent sample t-test was employed for statistical analyses and the receiver operating characteristic (ROC) curve for evaluating the diagnosis efficiency of SIDR and ADCDR values. Significant differences were observed in SIDR between benign and malignant breast lesions with b values of 0-400, 400-800 and 800-1 000 s/mm². The sensitivities of SIDR for differentiating benign and malignant breast lesions were 61.2%, 68.2% and 67.1%, the specificities 74.0%, 85.7% and 67.5%, the diagnosis accordance rates 67.3%, 76.5% and 67.3%, the positive predictive values 72.2%, 84.1% and 69.5% and the negative predictive values 63.3%, 71.0% and 65.0% respectively. Significant differences were observed in ADCDR between benign and malignant breast lesions with b values of 400-800 s/mm² and 800-1 000 s/mm². The sensitivities of SDR for differentiating benign and malignant breast lesions were 80.0% and 65.9%, the specificities 72.7% and 65.0%, the diagnostic accordance rates 76.5% and 65.4%, the positive predictive values 76.4% and 67

  7. Diffusion-weighted MR imaging of the normal fetal lung

    International Nuclear Information System (INIS)

    Balassy, Csilla; Kasprian, Gregor; Weber, Michael; Hoermann, Marcus; Bankier, Alexander; Herold, Christian J.; Prayer, Daniela; Brugger, Peter C.; Csapo, Bence; Bammer, Roland

    2008-01-01

    To quantify apparent diffusion coefficient (ADC) changes in fetuses with normal lungs and to determine whether ADC can be used in the assessment of fetal lung development. In 53 pregnancies (20-37th weeks of gestation), we measured ADC on diffusion-weighted imaging (DWI) in the apical, middle, and basal thirds of the right lung. ADCs were correlated with gestational age. Differences between the ADCs were assessed. Fetal lung volumes were measured on T2-weighted sequences and correlated with ADCs and with age. ADCs were 2.13 ± 0.44 μm 2 /ms (mean ± SD) in the apex, 1.99 ± 0.42 μm 2 /ms (mean ± SD) in the middle third, and 1.91 ± 0.41 μm 2 /ms (mean ± SD) in the lung base. Neither the individual ADC values nor average ADC values showed a significant correlation with gestational age or with lung volumes. Average ADCs decreased significantly from the lung apex toward the base. Individual ADCs showed little absolute change and heterogeneity. Lung volumes increased significantly during gestation. We have not been able to identify a pattern of changes in the ADC values that correlate with lung maturation. Furthermore, the individual, gravity-related ADC changes are subject to substantial variability and show nonuniform behavior. ADC can therefore not be used as an indicator of lung maturity. (orig.)

  8. Diffusion-weighted MR imaging of the normal fetal lung

    Energy Technology Data Exchange (ETDEWEB)

    Balassy, Csilla; Kasprian, Gregor; Weber, Michael; Hoermann, Marcus; Bankier, Alexander; Herold, Christian J.; Prayer, Daniela [Medical University of Vienna, Department of Radiology, Vienna (Austria); Brugger, Peter C. [Medical University of Vienna, Center of Anatomy and Cell Biology, Vienna (Austria); Csapo, Bence [Medical University of Vienna, Department of Obstetrics and Gyneocology, Vienna (Austria); Bammer, Roland [University of Stanford, Department of Radiology, Stanford, CA (United States)

    2008-04-15

    To quantify apparent diffusion coefficient (ADC) changes in fetuses with normal lungs and to determine whether ADC can be used in the assessment of fetal lung development. In 53 pregnancies (20-37th weeks of gestation), we measured ADC on diffusion-weighted imaging (DWI) in the apical, middle, and basal thirds of the right lung. ADCs were correlated with gestational age. Differences between the ADCs were assessed. Fetal lung volumes were measured on T2-weighted sequences and correlated with ADCs and with age. ADCs were 2.13 {+-} 0.44 {mu}m{sup 2}/ms (mean {+-} SD) in the apex, 1.99 {+-} 0.42 {mu}m{sup 2}/ms (mean {+-} SD) in the middle third, and 1.91 {+-} 0.41 {mu}m{sup 2}/ms (mean {+-} SD) in the lung base. Neither the individual ADC values nor average ADC values showed a significant correlation with gestational age or with lung volumes. Average ADCs decreased significantly from the lung apex toward the base. Individual ADCs showed little absolute change and heterogeneity. Lung volumes increased significantly during gestation. We have not been able to identify a pattern of changes in the ADC values that correlate with lung maturation. Furthermore, the individual, gravity-related ADC changes are subject to substantial variability and show nonuniform behavior. ADC can therefore not be used as an indicator of lung maturity. (orig.)

  9. Diffusion-weighted MR imaging of neuro-Behcet's disease: a case report

    International Nuclear Information System (INIS)

    Hiwatashi, Akio; Moritani, Toshio; Kinoshita, Toshibumi; Westesson, Per-Lennart; Garber, Todd

    2003-01-01

    We present a serial study of diffusion-weighted imaging (DWI) in a patient with neuro-Behcet's disease. Initial T2-weighted magnetic resonance images showed a hyperintense lesion in the brain stem. The lesion was slightly hyperintense on DWI and the apparent diffusion coefficient (ADC) was slightly increased. Ten months later, DWI showed an improvement in the abnormal signal intensity and the region of increased ADC had increased in size, especially on the left side. DWI is useful for differentiating an acute exacerbation of neuro-Behcet's disease from acute infarction. (orig.)

  10. Direct measurement of the signal intensity of diffusion-weighted magnetic resonance imaging for preoperative grading and treatment guidance for brain gliomas

    Directory of Open Access Journals (Sweden)

    Chih-Chun Wu

    2012-11-01

    Conclusion: The proposed method – direct measuring of tumor signal intensity of DWI on PACS monitors – is feasible for grading gliomas in clinical neuro-oncology imaging services and has a high level of reliability and reproducibility.

  11. Diffusion weighted MR imaging of pancreatic islet cell tumors

    International Nuclear Information System (INIS)

    Bakir, Baris; Salmaslioglu, Artur; Poyanli, Arzu; Rozanes, Izzet; Acunas, Bulent

    2010-01-01

    Purpose: The aim of our study is to demonstrate the feasibility of body diffusion weighted (DW) MR imaging in the evaluation of pancreatic islet cell tumors (ICTs) and to define apparent diffusion coefficient (ADC) values for these tumors. Materials and methods: 12 normal volunteers and 12 patients with histopathologically proven pancreatic ICT by surgery were included in the study. DW MR images were obtained by a body-phased array coil using a multisection single-shot echo planar sequence on the axial plane without breath holding. In addition, the routine abdominal imaging protocol for pancreas was applied in the patient group. We measured the ADC value within the normal pancreas in control group, pancreatic ICT, and surrounding pancreas parenchyma. Mann-Whitney U-test has been used to compare ADC values between tumoral tissues and normal pancreatic tissues of the volunteers. Wilcoxon Signed Ranks Test was preferred to compare ADC values between tumoral tissues and surrounding pancreatic parenchyma of the patients. Results: In 11 patients out of 12, conventional MR sequences were able to demonstrate ICTs successfully. In 1 patient an indistinct suspicious lesion was noted at the pancreatic tail. DW sequence was able to demonstrate the lesions in all of the 12 patients. On the DW images, all ICTs demonstrated high signal intensity relative to the surrounding pancreatic parenchyma. The mean and standard deviations of the ADC values (x10 -3 mm 2 /s) were as follows: ICT (n = 12), 1.51 ± 0.35 (0.91-2.11), surrounding parenchyma (n = 11) 0.76 ± 0.15 (0.51-1.01) and normal pancreas in normal volunteers (n = 12), 0.80 ± 0.06 (0.72-0.90). ADC values of the ICT were significantly higher compared with those of surrounding parenchyma (p < 0.01) and normal pancreas (p < 0.001). Conclusion: DW MR imaging does not appear to provide significant contribution to routine MR imaging protocol in the evaluation of pancreatic islet cell tumors. But it can be added to MR imaging

  12. Functional evaluation of the kidney by diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Hasegawa, Taro; Hasegawa, Norio; Irie, Takeo; Fukuda, Kunihiko

    2003-01-01

    The purpose of this study was to determine the relationship between the apparent diffusion coefficient (ADC) and diffuse renal disease by diffusion-weighted echo planar magnetic resonance (MR) imaging (EPI). Ten volunteers, seven patients with chronic renal failure and eighteen recipients of renal transplants were examined with diffusion-weighted EPI. We compared renal function (serum creatinine level) with provided ADC value. The average ADC values were 2.63 x 10 -3 mm 2 /sec for the whole kidney, 2.67 x 10 -3 mm 2 /sec for the cortex and 2.61 x 10 -3 mm 2 /sec for the medulla in normal kidneys. ADC values in the whole kidney, the cortex and the medulla in chronic renal failure were significantly lower than those for normal kidneys. In renal transplantation kidneys, the ADC values in the cortex were significantly lower than those for normal kidney. There was a linear correlation between ADC value and serum creatinine level. Our results show that diffusion-weighted MR imaging may be useful to identify renal dysfunction. (author)

  13. Clinical study of diffusion weighted imaging in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Chen Yunbin; Mao Yu; Pan Jianji; Hu Chunmiao

    2009-01-01

    Objective: To determine the diagnostic value of diffusion weighted imaging (DWI) for primary nasopharyngeal carcinoma(NPC) and metastatic lymph nodes, and to establish the diagnostic threshold of apparent diffusion coefficients(ADCs). Methods: Conventional MR scans and DWI scans were continuously performed in 56 patients with newly diagnosed NPC and 55 healthy volunteers. All patients received primary tumor biopsy and MR image-guided cervical lymph node fine-needle biopsy. ADC and eADC values of both primary lesions and lymph nodes were calculated and compared. Results: According to the pathological diagnosis, all the 56 patients had non-keratinizing carcinoma and 51 had lymph node metastasis. In the control group, 75 cervical lymph nodes were found. ADC values of both primary NPC and metastatic lymph nodes were significantly lower, while eADC values were higher than those of normal controls. Setting the ADC value threshold at 0.809 x 10 -3 mm 2 /s, the sensitivity and specificity for primary NPC detection were 80.4% and 74.5%, respectively. The negative and positive predictive values were 79.2% and 77.6%, respectively. The accuracy was 78.4%. Setting the ADC value threshold at 0.708 x 10 -3 mm 2 /s, the sensitivity and specificity in the detection of metastatic cervical lymph nodes were 43.1% and 93.3%, respectively. The negative and positive predictive values were 70.7% and 81.5%, respectively. The accuracy was 73.0%. Conclusions: DWI might be a new diagnostic approach in the detection of primary NPC as well as metastatic lymph nodes. (authors)

  14. Cervical Gross Tumor Volume Dose Predicts Local Control Using Magnetic Resonance Imaging/Diffusion-Weighted Imaging—Guided High-Dose-Rate and Positron Emission Tomography/Computed Tomography—Guided Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dyk, Pawel; Jiang, Naomi; Sun, Baozhou; DeWees, Todd A. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Fowler, Kathryn J.; Narra, Vamsi [Department of Diagnostic Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Garcia-Ramirez, Jose L.; Schwarz, Julie K. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Grigsby, Perry W., E-mail: pgrigsby@wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Gynecologic Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri (United States)

    2014-11-15

    Purpose: Magnetic resonance imaging/diffusion weighted-imaging (MRI/DWI)-guided high-dose-rate (HDR) brachytherapy and {sup 18}F-fluorodeoxyglucose (FDG) — positron emission tomography/computed tomography (PET/CT)-guided intensity modulated radiation therapy (IMRT) for the definitive treatment of cervical cancer is a novel treatment technique. The purpose of this study was to report our analysis of dose-volume parameters predicting gross tumor volume (GTV) control. Methods and Materials: We analyzed the records of 134 patients with International Federation of Gynecology and Obstetrics stages IB1-IVB cervical cancer treated with combined MRI-guided HDR and IMRT from July 2009 to July 2011. IMRT was targeted to the metabolic tumor volume and lymph nodes by use of FDG-PET/CT simulation. The GTV for each HDR fraction was delineated by use of T2-weighted or apparent diffusion coefficient maps from diffusion-weighted sequences. The D100, D90, and Dmean delivered to the GTV from HDR and IMRT were summed to EQD2. Results: One hundred twenty-five patients received all irradiation treatment as planned, and 9 did not complete treatment. All 134 patients are included in this analysis. Treatment failure in the cervix occurred in 24 patients (18.0%). Patients with cervix failures had a lower D100, D90, and Dmean than those who did not experience failure in the cervix. The respective doses to the GTV were 41, 58, and 136 Gy for failures compared with 67, 99, and 236 Gy for those who did not experience failure (P<.001). Probit analysis estimated the minimum D100, D90, and Dmean doses required for ≥90% local control to be 69, 98, and 260 Gy (P<.001). Conclusions: Total dose delivered to the GTV from combined MRI-guided HDR and PET/CT-guided IMRT is highly correlated with local tumor control. The findings can be directly applied in the clinic for dose adaptation to maximize local control.

  15. 18F-Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance in Lymphoma: Comparison With 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography and With the Addition of Magnetic Resonance Diffusion-Weighted Imaging.

    Science.gov (United States)

    Giraudo, Chiara; Raderer, Markus; Karanikas, Georgios; Weber, Michael; Kiesewetter, Barbara; Dolak, Werner; Simonitsch-Klupp, Ingrid; Mayerhoefer, Marius E

    2016-03-01

    The aim of this study was to compare F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/magnetic resonance (MR) (with and without diffusion-weighted imaging [DWI]) to F-FDG PET/computed tomography (CT), with regard to the assessment of nodal and extranodal involvement, in patients with Hodgkin lymphoma and non-Hodgkin lymphoma, without restriction to FDG-avid subytpes. Patients with histologically proven lymphoma were enrolled in this prospective, institutional review board-approved study. After a single F-FDG injection, patients consecutively underwent F-FDG PET[Fraction Slash]CT and F-FDG PET/MR on the same day for staging or restaging. Three sets of images were analyzed separately: F-FDG PET/CT, F-FDG PET/MR without DWI, and F-FDG PET/MR with DWI. Region-based agreement and examination-based sensitivity and specificity were calculated for F-FDG PET/CT, F-FDG PET/MR without DWI, and F-FDG PET/MR DWI. Maximum and mean standardized uptake values (SUVmax, SUVmean) on F-FDG PET/CT and F-FDG PET/MR were compared and correlated with minimum and mean apparent diffusion coefficients (ADCmin, ADCmean). Thirty-four patients with a total of 40 examinations were included. Examination-based sensitivities for F-FDG PET/CT, F-FDG PET/MR, and F-FDG PET/MR DWI were 82.1%, 85.7%, and 100%, respectively; specificities were 100% for all 3 techniques; and accuracies were 87.5%, 90%, and 100%, respectively. F-FDG PET/CT was false negative in 5 of 40 examinations (all with mucosa-associated lymphoid tissue lymphoma), and F-FDG PET/MR (without DWI) was false negative in 4 of 40 examinations. Region-based percentages of agreement were 99% (κ, 0.95) between F-FDG PET/MR DWI and F-FDG PET/CT, 99.2% (κ, 0.96) between F-FDG PET/MR and F-FDG PET/CT, and 99.4% (κ, 0.97) between F-FDG PET/MR DWI and F-FDG PET/MR. There was a strong correlation between F-FDG PET/CT and F-FDG PET/MR for SUVmax (r = 0.83) and SUVmean (r = 0.81) but no significant correlation between ADCmin and SUVmax

  16. Diffusion-weighted imaging of skeletal muscle lymphoma

    International Nuclear Information System (INIS)

    Surov, Alexey; Behrmann, Curd

    2014-01-01

    Muscle lymphoma (ML) is a relatively uncommon condition. On magnetic resonance imaging (MRI), ML can manifest with a broad spectrum of radiological features. The aim of this study was to demonstrate the features of DW images of muscle lymphoma (ML). In our database, ten patients (six women and four men) with ML were identified who were investigated by magnetic resonance imaging including acquisition of DW images. DW images were obtained using a multi-shot SE-EPI pulse sequence. Apparent diffusion constant (ADC) maps were also calculated. Furthermore, fusion images were generated manually from DW and HASTE or T2W images. On T2W images, all recognized lesions were hyperintense in comparison to unaffected musculature and on T1W images they were homogeneously hypointense. All lesions demonstrated low signal intensity on ADC images. The calculated ADC values ranged from 0.60 to 0.90 mm 2 s -1 (mean value 0.76 ± 0.10; median value 0.78). On fusion images, all lesions showed high signal intensity. ML demonstrated low ADC values and high signal intensity on fusion images suggesting high cellularity of the lesions. (orig.)

  17. Echo Planar Diffusion-Weighted Imaging: Possibilities and Considerations with 12- and 32-Channel Head Coils

    Directory of Open Access Journals (Sweden)

    John N Morelli

    2012-01-01

    Full Text Available Interest in clinical brain magnetic resonance imaging using 32-channel head coils for signal reception continues to increase. The present investigation assesses possibilities for improving diffusion-weighted image quality using a 32-channel in comparison to a conventional 12-channel coil. The utility of single-shot (ss and an approach to readout-segmented (rs echo planar imaging (EPI are examined using both head coils. Substantial image quality improvements are found with rs-EPI. Imaging with a 32-channel head coil allows for implementation of greater parallel imaging acceleration factors or acquisition of scans at a higher resolution. Specifically, higher resolution imaging with rs-EPI can be achieved by increasing the number of readout segments without increasing echo-spacing or echo time to the degree necessary with ss-EPI - a factor resulting in increased susceptibility artifact and reduced signal-to-noise with the latter.

  18. Diffusion-weighted imaging in patients with progressive multifocal leukoencephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Cosottini, M. [University of Pisa, Department of Neuroscience, Pisa (Italy); Service of Neuroradiology AO, Pisa (Italy); Tavarelli, C.; De Cori, S.; Bartolozzi, C. [University of Pisa, Department of Radiology, Pisa (Italy); Del Bono, L.; Doria, G. [Unit of Infectious Diseases AO, Pisa (Italy); Giannelli, M. [Unit of Medical Physics, Pisa (Italy); Michelassi, M.C. [Service of Neuroradiology AO, Pisa (Italy); Murri, L. [University of Pisa, Department of Neuroscience, Pisa (Italy)

    2008-05-15

    Progressive multifocal leukoencephalopathy (PML) is a severe demyelinating disease of the central nervous system due to JC polyoma virus infection of oligodendrocytes. PML develops in patients with impaired T-cell function as occurs in HIV, malignancy or immunosuppressive drugs users. Until now no imaging methods have been reported to correlate with clinical status. Diffusion-weighted imaging (DWI) is a robust MRI tool in investigating white matter architecture and diseases. The aim of our work was to assess diffusion abnormalities in focal white matter lesions in patients with PML and to correlate the lesion load measured with conventional MRI and DWI to clinical variables. We evaluated eight patients with a biopsy or laboratory-supported diagnosis of PML. All patients underwent MRI including conventional sequences (fluid attenuated inversion recovery-FLAIR) and DWI. Mean diffusivity (MD) maps were used to quantify diffusion on white matter lesions. Global lesion load was calculated by manually tracing lesions on FLAIR images, while total, central core and peripheral lesion loads were calculated by manually tracing lesions on DWI images. Lesion load obtained with the conventional or DWI-based methods were correlated with clinical variables such as disease duration, disease severity and survival. White matter focal lesions are characterized by a central core with low signal on DWI images and high MD (1.853 x 10{sup -3} mm2/s), surrounded by a rim of high signal intensity on DWI and lower MD (1.1 x 10{sup -3} mm2/s). The MD value of normal-appearing white matter is higher although not statistically significant (0.783 x 10{sup -3} mm2/s) with respect to control subjects (0.750 x 10{sup -3} mm2/s). Inter-rater correlations of global lesion load between FLAIR (3.96%) and DWI (3.43%) was excellent (ICC =0.87). Global lesion load on FLAIR and DWI correlates with disease duration and severity (respectively, p = 0.037, p = 0.0272 with Karnofsky scale and p = 0.0338 with

  19. Preliminary study on hypoxic-ischemic encephalopathy in neonates with diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Wang Xiaoming; Chen Liying; Lin Nan; Guo Qiyong

    2005-01-01

    Objective: To evaluate hypoxic-ischemic encephalopathy (HIE) in neonates with diffusion-weighted MR imaging, and to explore the value and limitation of diffusion-weighted imaging (DWI) compared with conventional magnetic resonance imaging. Methods: Conventional magnetic resonance T 1 -weighted imaging (T 1 WI) and DWI (b=700 s/mm 2 ) were performed in 36 neonates with HIE (average age, 8.44 days; range, 3 hours to 22 days), and the cortex and subcortical white matter, deep white matter, basal ganglia and thalamus, cerebral ventricle, and extra-cerebral interspace etc were observed. Results: Signal abnormalities were shown on DWI with hypoxic-ischemic insults, which included diffuse brain damage (19.4%, 7/36): extensive high signals in the regional cortex, subcortical and deep white matter; localized brain damage: high signals along lateral ventricular wall and triangular part (27.8%, 10/36 ), and punctate high signals in the frontal deep white matter (5.6%, 2/36). On T 1 WI, the incidence of the corresponding changes were 16.7% (6/36), 36.1% (13/36), and 30.6%(11/36), respectively. Hemorrhagic lesions demonstrated high signals on T 1 WI and no signals on DWI. Conclusion: DWI was applicable for acute HIE, and T 1 WI was suitable for subacute and chronic HIE. (authors)

  20. Diffusion-weighted MR imaging of transplanted kidneys: Preliminary report

    International Nuclear Information System (INIS)

    Wypych-Klunder, Katarzyna; Adamowicz, Andrzej; Lemanowicz, Adam; Szczęsny, Wojciech; Włodarczyk, Zbigniew; Serafin, Zbigniew

    2014-01-01

    An aim of this study was to assess the feasibility of DWI in the early period after kidney transplantation. We also aimed to compare ADC and eADC values in the cortex and medulla of the kidney, to estimate image noise and variability of measurements, and to verify possible relation between selected labolatory results and diffusion parameters in the transplanted kidney. Examinations were performed using a 1.5 T MR unit. DWI (SE/EPI) was performed in the axial plane using b-values of 600 and 1000. ADC and eADC measurements were performed in four regions of interest within the renal cortex and in three regions within the medulla. Relative variability of results and signal-to-noise ratio (SNR) were calculated. The analysis included 15 patients (mean age 52 years). The mean variability of ADC was significantly lower than that of eADC (6.8% vs. 10.8%, respectively; p<0.0001). The mean variability of measurements performed in the cortex was significantly lower than that in the medulla (6.2% vs. 11.5%, respectively; p<0.005). The mean SNR was higher in the measurements using b600 than b1000, it was higher in ADC maps than in the eADC maps, and it was higher in the cortex than in the medulla. ADC and eADC measured at b1000 in the cortex were higher in the group of the patients with eGFR ≤30 ml/min./1.73 m 2 as compared to patients with eGFR >30 ml/min./1.73 m 2 (p<0.05). Diffusion-weighted imaging of transplanted kidneys is technically challenging, especially in patients in the early period after transplantation. From a technical point of view, the best quality parameters offer quality ADC measurement in the renal cortex using b1000. ADC and eADC values in the renal cortex measured at b1000 present a relationship with eGFR

  1. Diffusion tensor and diffusion weighted imaging. Pictorial mathematics

    Energy Technology Data Exchange (ETDEWEB)

    Nakada, Tsutomu [California Univ., Davis, CA (United States)

    1995-06-01

    A new imaging algorithm for the treatment of a second order apparent diffusion tensor, D{sub app}{sup {xi}} is described. The method calls for only mathematics of images (pictorial mathematics) without necessity of eigenvalues/eigenvectors estimation. Nevertheless, it is capable of extracting properties of D{sub app}{sup {xi}} invariant to observation axes. While trace image is an example of images weighted by invariance of the tensor matrix, three dimensional anisotropy (3DAC) contrast represents the imaging method making use to anisotropic direction of tensor ellipsoid producing color coded contrast of exceptionally high anatomic resolution. Contrary to intuition, the processes require only a simple algorithm directly applicable to clinical magnetic resonance imaging (MRI). As a contrast method which precisely represents physical characteristics of a target tissue, invariant D{sub app}{sup {xi}} images produced by pictorial mathematics possess significant potential for a number of biological and clinical applications. (author).

  2. Diffusion-weighted MR imaging of non-complicated hepatic cysts: Value of 3T computed diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Nakamura, Yuko; Higaki, Toru; Akiyama, Yuji; Fukumoto, Wataru; Kajiwara, Kenji; Kaichi, Yoko; Honda, Yukiko; Komoto, Daisuke; Tatsugami, Fuminari; Iida, Makoto; Ohmoto, Toshifumi; Date, Shuji; Awai, Kazuo

    2016-01-01

    To investigate the utility of computed 3T diffusion-weighted imaging (c-DWI) for the diagnosis of non-complicated hepatic cysts with a focus on the T2 shine-through effect. In 50 patients with non-complicated hepatic cysts we acquired one set of DWIs (b-value 0 and 1000 s/mm 2 ) at 1.5T, and two sets at 3T (b-value 0 and 1000 s/mm 2 , TE 70 ms; b-value 0 and 600 s/mm 2 , TE 60 ms). We defined the original DWIs acquired with b = 1000 s/mm 2 at 1.5T and 3T as “o-1.5T-1000” and “o-3T-1000”. c-DWIs were calculated with 3T DWI at b-values of 0 and 600 s/mm 2 . c-DWI with b = 1000 and 1500 s/mm 2 were defined as “c-1000” and “c-1500”. Radiologists evaluated the signal intensity (SI) of the cysts using a 3-point score where 1 = not visible, 2 = discernible, and 3 = clearly visible. They calculated the contrast ratio (CR) between the cysts and the surrounding liver parenchyma on each DWIs and recorded the apparent diffusion coefficient (ADC) with a b-value = 0 and 1000 s/mm 2 on 1.5T- and 3T DWIs. Compared with o-1.5T-1000 DWI, the visual scores of all but the c-1500 DWIs were higher (p = 0.07 for c-1500- and p < 0.01 for the other DWIs). The CR at b = 1000 s/mm 2 was higher on o-3T-1000- than on o-1.5T-1000- (p < 0.01) but not higher than on c-1500 DWIs (p = 0.96). The CR at b = 0 s/mm 2 on 3T images with TE 70 ms was higher than on 1.5T images (p < 0.01). The ADC value was higher for 3T- than 1.5T images (p < 0.01). Non-complicated hepatic cysts showed higher SI on o-3T-1000- than o-1.5T-1000 DWIs due to the T2-shine through effect. This high SI was suppressed on c-1500 DWIs

  3. Brain MRI diffusion-weighted imaging in patients with classical phenylketonuria

    International Nuclear Information System (INIS)

    Manara, Renzo; Citton, Valentina; Carollo, Carla; Burlina, Alessandro P.; Ermani, Mario; Vespignani, Francesco; Burlina, Alberto B.

    2009-01-01

    The aim of this study was to grade magnetic resonance white matter abnormalities (WMAs) of classical phenylketonuria (cPKU) patients treated from birth and to compare sensitivity and specificity of T2-weighted and diffusion-weighted images (DWI). Twenty early-treated cPKU patients still on a low-phenylalanine diet (12 males; mean age 21.2 years) and 26 normal subjects (ten males; mean age 25.1 years) were enrolled. Typical T2- and diffusion-weighted WMAs were semiquantitatively graded according to Thompson score (TS). Besides, a regional magnetic resonance imaging (MRI) score (mTS) was developed according to extension and intensity of WMAs. Phenylalanine and tyrosine plasma concentrations before performing MRI and the amino acid mean levels collected the year before MRI (Tyr year and Phe year ) were measured. No patient with Phe year concentration below 460 μmol/L showed WMAs. In cPKU patients, TS and mTS were significantly higher on DWI than on T2 images (3.50 vs 2.65 and 23.65 vs 15.85, respectively, p year levels. Among the different MR sequences, DWI seems to be the most sensitive and reliable in detecting and grading the typical WMAs of cPKU patients. (orig.)

  4. Diffusion-weighted MR imaging of the abdomen with pulse triggering

    International Nuclear Information System (INIS)

    Muertz, P.; Pauleit, D.; Traeber, F.; Kreft, B.P.; Schild, H.H.

    2000-01-01

    Purpose: The aim of this work was to reduce the influence of motion on diffusion-weighted MR images of the abdomen by pulse triggering of single-shot sequences. Methods: Five healthy volunteers were examined both without and with finger pulse-triggering of a diffusion-weighted single-shot echo planar MR imaging sequence at 1.5 T. Series of diffusion-weighted images were acquired at different phases of the cardiac cycle by varying the time delay between finger pulse and sequence acquisition. The measurements were repeated three times. The diffusion weighted images were analysed by measuring the signal intensities and by determining the ADC values within the spleen, kidney and liver. Results: The magnitude of motion artifacts on diffusion weighted images shows a strong dependence on the trigger delay. The optimum trigger delay is found to be between 500 and 600 ms. For these values the abdominal organs appear homogeneous on all diffusion weighted images and the strongest signal intensities are detected. At optimum triggering the accuracy of the apparent diffusion coefficients is up to 10 times better than without triggering. Moreover, the standard deviation of the repeated measurements is smaller than 12% for all volunteers and for all organs. Without triggering the standard deviation is larger by a factor of 4 on average. Conclusion: Pulse triggering of single-shot sequences leads to significant reduction of motion related artifacts on diffusion weighted images of the abdomen and provides more accurate and reproducible ADC values. (orig.) [de

  5. Diffusion-weighted imaging (DWI) in musculoskeletal MRI: a critical review

    Energy Technology Data Exchange (ETDEWEB)

    Khoo, Michael M.Y.; Tyler, Philippa A.; Saifuddin, Asif [Royal National Orthopaedic Hospital, Department of Radiology, Stanmore, Middlesex (United Kingdom); Padhani, Anwar R. [Mount Vernon Cancer Centre, Paul Strickland Scanner Centre, Northwood (United Kingdom)

    2011-06-15

    Magnetic resonance imaging (MRI) is the mainstay of diagnosis, staging and follow-up of much musculoskeletal pathology. Diffusion-weighted magnetic resonance imaging (DWI) is a recent addition to the MR sequences conventionally employed. DWI provides qualitative and quantitative functional information concerning the microscopic movements of water at the cellular level. A number of musculoskeletal disorders have been evaluated by DWI, including vertebral fractures, bone marrow infection, bone marrow malignancy, primary bone and soft tissue tumours; post-treatment follow-up has also been assessed. Differentiation between benign and malignant vertebral fractures by DWI and monitoring of therapy response have shown excellent results. However, in other pathologies, such as primary soft tissue tumours, DWI data have been inconclusive in some cases, contributing little additional information beyond that gained from conventional MR sequences. The aim of this article is to critically review the current literature on the contribution of DWI to musculoskeletal MRI. (orig.)

  6. Rocky Mountain spotted fever: 'starry sky' appearance with diffusion-weighted imaging in a child.

    Science.gov (United States)

    Crapp, Seth; Harrar, Dana; Strother, Megan; Wushensky, Curtis; Pruthi, Sumit

    2012-04-01

    We present a case of Rocky Mountain spotted fever encephalitis in a child imaged utilizing diffusion-weighted MRI. Although the imaging and clinical manifestations of this entity have been previously described, a review of the literature did not reveal any such cases reported in children utilizing diffusion-weighted imaging. The imaging findings and clinical history are presented as well as a brief review of this disease.

  7. Metabolomics of Breast Cancer Using High-Resolution Magic Angle Spinning Magnetic Resonance Spectroscopy: Correlations with 18F-FDG Positron Emission Tomography-Computed Tomography, Dynamic Contrast-Enhanced and Diffusion-Weighted Imaging MRI.

    Science.gov (United States)

    Yoon, Haesung; Yoon, Dahye; Yun, Mijin; Choi, Ji Soo; Park, Vivian Youngjean; Kim, Eun-Kyung; Jeong, Joon; Koo, Ja Seung; Yoon, Jung Hyun; Moon, Hee Jung; Kim, Suhkmann; Kim, Min Jung

    2016-01-01

    Our goal in this study was to find correlations between breast cancer metabolites and conventional quantitative imaging parameters using high-resolution magic angle spinning (HR-MAS) magnetic resonance spectroscopy (MRS) and to find breast cancer subgroups that show high correlations between metabolites and imaging parameters. Between August 2010 and December 2013, we included 53 female patients (mean age 49.6 years; age range 32-75 years) with a total of 53 breast lesions assessed by the Breast Imaging Reporting and Data System. They were enrolled under the following criteria: breast lesions larger than 1 cm in diameter which 1) were suspicious for malignancy on mammography or ultrasound (US), 2) were pathologically confirmed to be breast cancer with US-guided core-needle biopsy (CNB) 3) underwent 3 Tesla MRI with dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI) and positron emission tomography-computed tomography (PET-CT), and 4) had an attainable immunohistochemistry profile from CNB. We acquired spectral data by HR-MAS MRS with CNB specimens and expressed the data as relative metabolite concentrations. We compared the metabolites with the signal enhancement ratio (SER), maximum standardized FDG uptake value (SUV max), apparent diffusion coefficient (ADC), and histopathologic prognostic factors for correlation. We calculated Spearman correlations and performed a partial least squares-discriminant analysis (PLS-DA) to further classify patient groups into subgroups to find correlation differences between HR-MAS spectroscopic values and conventional imaging parameters. In a multivariate analysis, the PLS-DA models built with HR-MAS MRS metabolic profiles showed visible discrimination between high and low SER, SUV, and ADC. In luminal subtype breast cancer, compared to all cases, high SER, ADV, and SUV were more closely clustered by visual assessment. Multiple metabolites were correlated with SER and SUV in all cases. Multiple metabolites showed

  8. Metabolomics of Breast Cancer Using High-Resolution Magic Angle Spinning Magnetic Resonance Spectroscopy: Correlations with 18F-FDG Positron Emission Tomography-Computed Tomography, Dynamic Contrast-Enhanced and Diffusion-Weighted Imaging MRI.

    Directory of Open Access Journals (Sweden)

    Haesung Yoon

    Full Text Available Our goal in this study was to find correlations between breast cancer metabolites and conventional quantitative imaging parameters using high-resolution magic angle spinning (HR-MAS magnetic resonance spectroscopy (MRS and to find breast cancer subgroups that show high correlations between metabolites and imaging parameters.Between August 2010 and December 2013, we included 53 female patients (mean age 49.6 years; age range 32-75 years with a total of 53 breast lesions assessed by the Breast Imaging Reporting and Data System. They were enrolled under the following criteria: breast lesions larger than 1 cm in diameter which 1 were suspicious for malignancy on mammography or ultrasound (US, 2 were pathologically confirmed to be breast cancer with US-guided core-needle biopsy (CNB 3 underwent 3 Tesla MRI with dynamic contrast-enhanced (DCE and diffusion-weighted imaging (DWI and positron emission tomography-computed tomography (PET-CT, and 4 had an attainable immunohistochemistry profile from CNB. We acquired spectral data by HR-MAS MRS with CNB specimens and expressed the data as relative metabolite concentrations. We compared the metabolites with the signal enhancement ratio (SER, maximum standardized FDG uptake value (SUV max, apparent diffusion coefficient (ADC, and histopathologic prognostic factors for correlation. We calculated Spearman correlations and performed a partial least squares-discriminant analysis (PLS-DA to further classify patient groups into subgroups to find correlation differences between HR-MAS spectroscopic values and conventional imaging parameters.In a multivariate analysis, the PLS-DA models built with HR-MAS MRS metabolic profiles showed visible discrimination between high and low SER, SUV, and ADC. In luminal subtype breast cancer, compared to all cases, high SER, ADV, and SUV were more closely clustered by visual assessment. Multiple metabolites were correlated with SER and SUV in all cases. Multiple metabolites

  9. Diffusion-weighted MR imaging of kidneys in patients with chronic kidney disease: initial study

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xueqin; Fang, Wenqiang; Ling, Huawei; Chai, Weimin; Chen, Kemin [Ruijin Hospital Shanghai, Jiaotong University School of Medicine, Department of Radiology, Shanghai (China)

    2010-04-15

    To prospectively evaluate the feasibility of diffusion-weighted (DW) magnetic resonance (MR) imaging in the assessment of renal function in patients with chronic kidney disease (CKD). Seventy-two healthy volunteers and 43 patients underwent coronal echo-planar DW MR imaging of the kidneys with a single breath-hold time of 16 s. The patients were grouped according to five stages as indicated by the K/DOQI CKD (kidney disease outcome quality initiative). The apparent diffusion coefficient (ADC) value of the kidneys was calculated with high b values (b = 500 s/mm{sup 2}). The ADC values were compared between patients and healthy volunteers, and among different stages. For statistical analysis, Student's t tests, ANOVA, Pearson's correlation tests, and Spearman's correlation tests were used. No difference between the cortex and medulla could be observed on DW images of all volunteers. Patients with CKD had significantly lower renal ADC (t = -4.383, P = 0.000) than volunteers. The ADC values of kidneys were significantly lower than normal at most stages of CKD, except CKD1. There was a negative correlation between the ADCs and serum creatinine (sCr) level (P = 0.000) amongst the patients. Diffusion-weighted MR imaging is feasible in the assessment of renal function, especially in the detection of early stage renal failure of CKD. (orig.)

  10. Diffusion-weighted MR imaging of kidneys in patients with chronic kidney disease: initial study

    International Nuclear Information System (INIS)

    Xu, Xueqin; Fang, Wenqiang; Ling, Huawei; Chai, Weimin; Chen, Kemin

    2010-01-01

    To prospectively evaluate the feasibility of diffusion-weighted (DW) magnetic resonance (MR) imaging in the assessment of renal function in patients with chronic kidney disease (CKD). Seventy-two healthy volunteers and 43 patients underwent coronal echo-planar DW MR imaging of the kidneys with a single breath-hold time of 16 s. The patients were grouped according to five stages as indicated by the K/DOQI CKD (kidney disease outcome quality initiative). The apparent diffusion coefficient (ADC) value of the kidneys was calculated with high b values (b = 500 s/mm 2 ). The ADC values were compared between patients and healthy volunteers, and among different stages. For statistical analysis, Student's t tests, ANOVA, Pearson's correlation tests, and Spearman's correlation tests were used. No difference between the cortex and medulla could be observed on DW images of all volunteers. Patients with CKD had significantly lower renal ADC (t = -4.383, P = 0.000) than volunteers. The ADC values of kidneys were significantly lower than normal at most stages of CKD, except CKD1. There was a negative correlation between the ADCs and serum creatinine (sCr) level (P = 0.000) amongst the patients. Diffusion-weighted MR imaging is feasible in the assessment of renal function, especially in the detection of early stage renal failure of CKD. (orig.)

  11. Incidence of postangiographic silent brain infarction detected by diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Mori, Harushi; Hayashi, Naoto; Aoki, Shigeki

    2002-01-01

    We surveyed to assess for the incidence of clinically silent brain infarction after cerebral catheter angiography. Diffusion-weighted images were performed shortly after 33 cerebral catheter angiographies. We found totally 11 abnormally high intensity spots in 5 of 33 patients on diffusion-weighted images and, therefore, the incidence was calculated as 15.2%. This incidence is higher than has been estimated based on the incidence of neurological deficits (about 0.5%) after cerebral angiography. Diffusion-weighted MR imaging is suitable to monitor the safety of angiographic procedures and material. (author)

  12. Diffusion-weighted MR imaging in biopsy-proven Creutzfeldt-Jakob disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo Cheol; Chang, Kee Hyun; Song In Chan; Lee, Sang Hyun; Kwon, Bae Ju; Han, Moon Hee; Kim, Sang Yun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2001-12-01

    To compare conventional and diffusion-weighted MR imaging in terms of their depiction of the abnormalities occurring in Creutzfeldt-Jakob disease. We retrospectively analyzed the findings of conventional (T2-weighted and fluid-attenuated inversion recovery) and diffusion-weighted MR imaging in four patients with biopsy-proven Creutzfeldt-Jakob disease. The signal intensity of the lesion was classified by visual assessment as markedly high, slightly high, or isointense, relative to normal brain parenchyma. Both conventional and diffusion-weighted MR images demonstrated bilateral high signal intensity in the basal ganglia in all four patients. Cortical lesions were observed on diffusion-weighted MR images in all four, and on fluidattenuated inversion recovery MR images in one, but in no patient on T2-weighted images. Conventional MR images showed slightly high signal intensity in all lesions, while diffusion-weighted images showed markedly high signal intensity in most. Diffusion-weighted MR imaging is more sensitive than its conventional counterpart in the depiction of Creutzfeldt-Jakob disease, and permits better detection of the lesion in both the cerebral cortices and basal ganglia.

  13. Diffusion-weighted MR imaging in biopsy-proven Creutzfeldt-Jakob disease

    International Nuclear Information System (INIS)

    Kim, Hyo Cheol; Chang, Kee Hyun; Song In Chan; Lee, Sang Hyun; Kwon, Bae Ju; Han, Moon Hee; Kim, Sang Yun

    2001-01-01

    To compare conventional and diffusion-weighted MR imaging in terms of their depiction of the abnormalities occurring in Creutzfeldt-Jakob disease. We retrospectively analyzed the findings of conventional (T2-weighted and fluid-attenuated inversion recovery) and diffusion-weighted MR imaging in four patients with biopsy-proven Creutzfeldt-Jakob disease. The signal intensity of the lesion was classified by visual assessment as markedly high, slightly high, or isointense, relative to normal brain parenchyma. Both conventional and diffusion-weighted MR images demonstrated bilateral high signal intensity in the basal ganglia in all four patients. Cortical lesions were observed on diffusion-weighted MR images in all four, and on fluidattenuated inversion recovery MR images in one, but in no patient on T2-weighted images. Conventional MR images showed slightly high signal intensity in all lesions, while diffusion-weighted images showed markedly high signal intensity in most. Diffusion-weighted MR imaging is more sensitive than its conventional counterpart in the depiction of Creutzfeldt-Jakob disease, and permits better detection of the lesion in both the cerebral cortices and basal ganglia

  14. Clinical application of EPI diffusion weighted image (DWI) for ischemic brain disease

    International Nuclear Information System (INIS)

    Zenke, Kiichiro; Kusunoki, Katsusuke; Saito, Masahiro; Sadamoto, Kazuhiko; Sakaki, Saburo; Kumon, Yoshiaki; Nagasawa, Kiyoshi

    1999-01-01

    Diffusion-weighted magnetic resonance image (DWI) with Echo Planar imaging (EPI) techniques were utilized in 74 consecutive patients who were suspected or diagnosed as having occlusive cerebrovascular diseases. Of three EPI-DWI techniques-single shot DWI, multi-shot DWI and isotropic DWI-, isotropic DWI was the most useful study for diagnosing occlusive cerebro-vascular disease. EPI-DWI could identify fresh infarction, even small cortical infarctions, in the setting of multiple high intensity lesions shown by T2 weighted image (T2WI), and could detect infarcted lesions early after the onset. In the patients whose lesions were not revealed on the initial EPI-DWIs, new infarcted lesion were not found on later MRIs, and their symptoms disappeared completely. High intensity lesions observed on EPI-DWIs mostly decreased signal intensities about 2 weeks after the onset, and the intensities of lesions in the gray matter were reduced earlier than those in the white matter. (author)

  15. Marchiafava-Bignami disease with hyperintensity on late diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Iwai, Takayasu; Matsuo, Koushun; Morii-Kitani, Fukiko; Azuma, Fumiko; Matsuo, Hisayasu; Takada, Masahiko; Nakagawa, Masanori; Mizuno, Toshiki; Yamada, Kei

    2014-01-01

    A 69-year-old man with a decades-long history of chronic alcohol consumption was admitted with gait disturbance (short steps and spasticity), deterioration of activity, and stuporous consciousness. Head magnetic resonance imaging (MRI) revealed hyperintensity on fluid-attenuated inversion recovery imaging in the corpus callosum and frontal white matter. The lesion later became more apparent on diffusion-weighted imaging. The clinical diagnosis was Marchiafava-Bignami disease (MBD). As temporary treatment, refraining from alcohol consumption and administration of vitamins were prescribed. The condition of the patient gradually improved. The purposes of this study were to demonstrate the clinical and radiological variety of MBD and to identify practical methods of treatment of this pathology

  16. Apparent Diffusion Coefficient Maps of Pediatric Mass Lesions with Free-Breathing Diffusion-Weighted Magnetic Resonance: Feasibility Study

    International Nuclear Information System (INIS)

    Olsen, Oe.E.; Sebire, N.J.

    2006-01-01

    Purpose: To assess the technical feasibility of apparent diffusion coefficient (ADC) mapping based on free-breathing diffusion-weighted magnetic resonance (DW-MR) outside the CNS in children. Material and Methods: Twelve children with mass lesions of varied histopathology were scanned with short-tau inversion recovery (STIR), contrast-enhanced T1-weighted (CE-T1W), and diffusion-weighted (b = 0, 500 and 1,000 s/mm 2 ) sequences. ADC maps were calculated. Lesion-to-background signal intensity ratios were measured and compared between STIR/CE-T1W/ADC overall (Friedman test) and between viable embryonal tumors and other lesions (Kruskal-Wallis test). Results: ADC maps clearly depicted all lesions. Lesion-to-background signal intensity ratios of STIR (median 3.7), CE-T1W (median 1.4), and ADC (median 1.6) showed no overall difference (chi-square = 3.846; P = 0.146), and there was no difference between viable embryonal tumors and other lesions within STIR/CE-T1W/ADC (chi-square 1.118/0.669/<0.001; P = 0.290/0.414/1.000, respectively). Conclusion: ADC mapping is feasible in free-breathing imaging of pediatric mass lesions outside the CNS using standard clinical equipment. Keywords: Diffusion-weighted magnetic resonance imaging; infants and children; neoplasms

  17. Incidence of ischemic lesions in diffusion-weighted imaging after transbrachial digital subtraction angiography

    International Nuclear Information System (INIS)

    Aschenbach, R.; Majeed, A.; Eger, C.; Basche, S.; Kerl, J.M.; Vogl, T.J.

    2008-01-01

    Purpose: to evaluate the frequency of ischemia after transbrachial digital subtraction angiography under ambulant conditions using diffusion-weighted imaging. Materials and methods: 200 patients were included in a prospective study design and received transbrachial digital subtraction angiography under ambulant conditions. Before and after digital subtraction angiography, diffusion-weighted imaging of the brain was performed. Results: in our study population no new lesions were found in diffusion-weighted imaging after digital subtraction angiography during the 3-hour window after angiography. One new lesion was found 3 days after angiography as a late onset complication. Therefore, the frequency of neurological complications is at the level of the confidence interval of 0 - 1.5%. Conclusion: the transbrachial approach under ambulant conditions is a safe method for digital subtraction angiography resulting in a low rate of ischemic lesions in diffusion-weighted imaging. (orig.)

  18. Role of diffusion-weighted MR imaging in characterization of cervical lesions

    International Nuclear Information System (INIS)

    Salik, E.; Islim, F.; Ciftci, G.; Bayramoglu, S.; Sever, N.

    2012-01-01

    Full text: Introduction: Characterization of neck lesions is usually not possible without histopathological examination. Objective: To evaluate whether adhesion diffusion coefficient (ADC) values calculated from diffusion weighted magnetic resonance imaging can be used to characterize neck lesions. Material and methods: Diffusion-weighted echo planar MR imaging with b factors of 0, 500 and 1000 sec/mm 2 was prospectively performed with a 1.5 T MR unit in 119 neck lesions in 119 patients. ADC values were measured by 2 radiologists independently on an independent workstation console. Intraclass correlation coefficients were calculated. The mean ADC values were compared using Mann-whitney u test. Results: There was a statistically significant difference between the mean ADC values of benign and malign solid lesions (1.13±0.62 x 10 -3 mm 2 /s and 0.82±0.21 x 10 -3 mm 2 /s respectively). There was no malign lesion with an ADC value more than 1.15 x 10 -3 mm 2 /s. The mean ADC value of malignant lymphomas (0.61±0.14 x 10 -3 ) was significantly smaller than the mean ADC values of other cervical lymphadenopathies. But there was no statistically significant difference between the mean ADC values of reactive, granulomatous and metastatic lymph nodes. Conclusion: ADC values cannot totally distinguish the histopathological subgroups of the neck lesions but shows significant differences between malign and benign lesions.

  19. Hemorrhagic brain metastases with high signal intensity on diffusion-weighted MR images. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Mori, H.; Abe, O.; Aoki, S.; Masumoto, T.; Yoshikawa, T.; Kunimatsu, A; Hayashi, N.; Ohtomo, K. [Graduate School of Medicine, Univ. of Tokyo (Japan). Dept. of Radiology

    2002-11-01

    Diffusion-weighted MR imaging has been applicable to the differential diagnosis of abscesses and necrotic or cystic brain tumors. However, restricted water diffusion is not necessarily specific for brain abscess. We describe ring-enhancing metastases of lung carcinoma characterized by high signal intensity on diffusion-weighted MR images. The signal pattern probably reflected intralesional hemorrhage. The present report adds to the growing literature regarding the differential diagnosis of ring-enhancing brain lesions.

  20. Brain MRI diffusion-weighted imaging in patients with classical phenylketonuria

    Energy Technology Data Exchange (ETDEWEB)

    Manara, Renzo; Citton, Valentina; Carollo, Carla [University Hospital of Padua, Neuroradiologic Unit, Padua (Italy); Burlina, Alessandro P.; Ermani, Mario [University Hospital of Padua, Neurological Clinic, Department of Neuroscience, Padua (Italy); Vespignani, Francesco; Burlina, Alberto B. [University Hospital of Padua, Metabolic Diseases Unit, Department of Paediatrics, Padua (Italy)

    2009-12-15

    The aim of this study was to grade magnetic resonance white matter abnormalities (WMAs) of classical phenylketonuria (cPKU) patients treated from birth and to compare sensitivity and specificity of T2-weighted and diffusion-weighted images (DWI). Twenty early-treated cPKU patients still on a low-phenylalanine diet (12 males; mean age 21.2 years) and 26 normal subjects (ten males; mean age 25.1 years) were enrolled. Typical T2- and diffusion-weighted WMAs were semiquantitatively graded according to Thompson score (TS). Besides, a regional magnetic resonance imaging (MRI) score (mTS) was developed according to extension and intensity of WMAs. Phenylalanine and tyrosine plasma concentrations before performing MRI and the amino acid mean levels collected the year before MRI (Tyr{sub year} and Phe{sub year}) were measured. No patient with Phe{sub year} concentration below 460 {mu}mol/L showed WMAs. In cPKU patients, TS and mTS were significantly higher on DWI than on T2 images (3.50 vs 2.65 and 23.65 vs 15.85, respectively, p<0.002, Wilcoxon test). All controls were scored 0 on DWI, while in T2 images, TS and mTS were 0.19 and 1.70. DWI evaluated by mTS disclosed a frontotemporal, occipital, and parietal WM progressive involvement. TS and mTS, both on T2 images and on DWI, showed no correlation with tyrosine while they proved to have a strong correlation with phenylalaninemia and an excellent one with Phe{sub year} levels. Among the different MR sequences, DWI seems to be the most sensitive and reliable in detecting and grading the typical WMAs of cPKU patients. (orig.)

  1. Posterior reversible encephalopathy syndrome: a case of unusual diffusion-weighted MR images.

    Science.gov (United States)

    Benziada-Boudour, A; Schmitt, E; Kremer, S; Foscolo, S; Rivière, A-S; Tisserand, M; Boudour, A; Bracard, S

    2009-05-01

    Posterior reversible encephalopathy (PRES) represents an uncommon entity related to multiple pathologies, the most common of which is hypertensive crisis. PRES is classically characterized as symmetrical parieto-occipital edema, but may affect other areas of the brain. Diffusion-weighted magnetic resonance imaging (DWI) is important for differentiating between vasogenic and cytotoxic edema. We present here the case of a 43-year-old woman, known to suffer from arterial hypertension and severe renal failure, who developed PRES with restricted apparent diffusion coefficients (ADC) in various cerebral areas, suggesting irreversible tissue damage. Nevertheless, follow-up cranial MRI revealed complete remission, indicating that restricted diffusion does not always lead to cell death in this pathology. The underlying pathophysiological mechanism is not well understood. Such reversibility of diffusion anomalies has already been reported with transient ischemia, vasospasm after subarachnoid hemorrhage and epilepsy but, to our knowledge, never before in PRES.

  2. Use of intravoxel incoherent motion diffusion-weighted imaging in identifying the vascular and avascular zones of human meniscus.

    Science.gov (United States)

    Guo, Tan; Chen, Juan; Wu, Bing; Zheng, Dandan; Jiao, Sheng; Song, Yan; Chen, Min

    2017-04-01

    To investigate the hypothesis that the intravoxel incoherent motion (IVIM) diffusion-weighted imaging may depict microcirculation of meniscus and the perfusion changes in meniscal disorder. Fifty patients received diffusion-weighted MRI with multiple b-values ranging from 0 to 400 s/mm 2 . The four horns of the menisci were divided into normal, degenerated, and torn groups. IVIM parameters including perfusion fraction (f), pseudo-diffusion coefficient (D*), true diffusion coefficient (D), and the product of f and D* (f D*) of normal meniscal red zone and white zone were derived and compared for microcirculation changes of normal, degenerated, and torn posterior horn of the medial meniscus (PMM). The parameters between red and white zones among the groups were compared. Significant differences were considered when P meniscus and the perfusion changes in meniscal disorder. 3 J. Magn. Reson. Imaging 2017;45:1090-1096. © 2016 International Society for Magnetic Resonance in Medicine.

  3. Detection of peritoneal dissemination in gynecological malignancy: evaluation by diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Fujii, Shinya; Matsusue, Eiji; Kanasaki, Yoshiko; Nakanishi, Junko; Sugihara, Shuji; Ogawa, Toshihide; Kanamori, Yasunobu; Kigawa, Junzo; Terakawa, Naoki

    2008-01-01

    The aim of this study is to evaluate the usefulness of diffusion-weighted (DW) magnetic resonance (MR) imaging in detecting peritoneal dissemination in cases of gynecological malignancy. We retrospectively analyzed MR images obtained from 26 consecutive patients with gynecological malignancy. Peritoneal dissemination was histologically diagnosed in 15 of the 26 patients after surgery. We obtained DW images and half-Fourier single-shot turbo-spin-echo images in the abdomen and pelvis, and then generated fusion images. Coronal maximum-intensity-projection images were reconstructed from the axial source images. Reader interpretations were compared with the laparotomy findings in the surgical records. Receiver-operating characteristic (ROC) curves were used to represent the presence of peritoneal dissemination. In addition, the sensitivity and specificity were calculated. DW imaging depicted the tumors in 14 of 15 patients with peritoneal dissemination as abnormal signal intensity. ROC analysis yielded Az values of 0.974 and 0.932 for the two reviewers. The mean sensitivity and specificity were 90 and 95.5%. DW imaging plays an important role in the diagnosis and therapeutic management of patients with gynecological malignancy. (orig.)

  4. Diffusion-Weighted Imaging and Diffusion Tensor Imaging of Asymptomatic Lumbar Disc Herniation

    OpenAIRE

    Sakai, Toshinori; Miyagi, Ryo; Yamabe, Eiko; Fujinaga, Yasunari; Bhatia, Nitin N.; Yoshioka, Hiroshi

    2014-01-01

    Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) were performedon a healthy 31-year-old man with asymptomatic lumbar disc herniation. Althoughthe left S1 nerve root was obviously entrapped by a herniated mass, neither DWI nor DTI showed any significant findings for the nerve root. Decreased apparent diffusion coefficient (ADC) values and increased fractional anisotropy (FA) values were found. These results are contrary to those in previously published studies of symptomatic...

  5. The utility of diffusion-weighted MR imaging for differentiating uterine sarcomas from benign leiomyomas

    International Nuclear Information System (INIS)

    Tamai, Ken; Saga, Tsuneo; Morisawa, Nobuko; Fujimoto, Koji; Togashi, Kaori; Koyama, Takashi; Mikami, Yoshiki

    2008-01-01

    The usefulness of diffusion-weighted (DW) magnetic resonance (MR) imaging for the diagnosis of uterine sarcomas was investigated, as well as whether DW images and quantitative measurement of apparent diffusion coefficient (ADC) values can facilitate differentiating uterine sarcomas from benign leiomyomas. MR images including DW images were obtained in 43 surgically treated patients with 58 myometrial tumors, including seven uterine sarcomas (five leiomyosarcomas and two endometrial stromal sarcomas) and 51 benign leiomyomas (43 ordinary leiomyomas, two cellular leiomyomas and six degenerated leiomyomas). Qualitative analysis of non-enhanced and postcontrast MR images and DW images and quantitative measurement of ADC values were performed for each myometrial tumor. Both uterine sarcomas and cellular leiomyomas exhibited high signal intensity on DW images, whereas ordinary leiomyomas and most degenerated leiomyomas showed low signal intensity. The mean ADC value (10 -3 mm 2 /s) of sarcomas was 1.17 ± 0.15, which was lower than those of the normal myometrium (1.62 ± 0.11) and degenerated leiomyomas (1.70 ± 0.11) without any overlap; however, they were overlapped with those of ordinary leiomyomas and cellular leiomyomas. In addition to morphological features on nonenhanced and postcontrast MR sequences, DW imaging and ADC measurement may have a potential ability to differentiate uterine sarcomas from benign leiomyomas. (orig.)

  6. Imaging Appearance of Human Immunodeficiency Virus Encephalitis on the Diffusion Weighted Images: A Case Report

    International Nuclear Information System (INIS)

    Lim, Hun Cheol; Yu, In Kyu; Oh, Keon Se

    2011-01-01

    Imaging finding of human immunodeficiency virus (HIV) encephalitis contain bilateral, symmetric, patchy, or diffuse increased T2WI signal intensities in the basal ganglia, cerebellum, brainstem, and centrum semiovale. In particular, the centrum semiovale is most commonly involved. Most of the HIV encephalitis cases are accompanied by brain atrophy. No previous study has reported symmetric increased signal intensity at the bilateral centrum semiovale without brain atrophy on diffusion weighted images in HIV encephalitis patients. Here, we report a case of this. We suggest that radiologists should consider the possibility of HIV encephalitis if there are symmetric increases in signal intensity at the bilateral centrum semiovale on diffusion weighted images of patients with a history of HIV infection.

  7. Principles and implementation of diffusion-weighted and diffusion tensor imaging

    International Nuclear Information System (INIS)

    Roberts, Timothy P.L.; Schwartz, E.S.

    2007-01-01

    We review the physiological basis of diffusion-weighted imaging and discuss the implementation of diffusion-weighted imaging pulse sequences and the subsequent postprocessing to yield quantitative estimations of diffusion parameters. We also introduce the concept of directionality of ''apparent'' diffusion in vivo and the means of assessing such anisotropy quantitatively. This in turn leads to the methodological application of diffusion tensor imaging and the subsequent postprocessing, known as tractography. The following articles deal with the clinical applications enabled by such methodologies. (orig.)

  8. MRI of paraventricular white matter lesions in amyotrophic lateral sclerosis. Analysis by diffusion-weighted images

    Energy Technology Data Exchange (ETDEWEB)

    Segawa, Fuminori; Kinoshita, Masao (Toho Univ., Tokyo (Japan). Ohashi Hospital); Kishibayashi, Jun; Kamada, Kazuhiko; Sunohara, Nobuhiko

    1994-09-01

    Magnetic resonance images in some cases of amyotrophic lateral sclerosis (ALS) revealed abnormal signals in both the paraventriculer white matter and in the posterior limbs of the internal capsule. We examined T[sub 2]- and diffusion-weighted MR images of these lesions in 18 cases of ALS. There were symmetrical high-signal areas in the posterior limbs of the internal capsule in all of the cases. The high-signal areas in the internal capsule corresponded to the pyramidal tracts in the anatomical atlas by Talairach. In 5 of the cases of ALS, T[sub 2]-weighted MR images showed discrete paraventricular white matter lesions as well. The mean age of the ALS patients with paraventricular white matter lesions was higher than that of the ALS patients without such lesions. Proton densities calculated from the conventional MR images were higher in both the capsular and paraventricular lesions. The diffusion coefficients perpendicular to the pyramidal tract in the internal capsular lesions were within the normal range, where as the diffusion coefficients in the paraventricular lesions were increased in all directions. Thus, diffusion anisotropy was lost in the paraventricular lesions. These findings are similar to those observed in the white matter lesions of cerebro-vascular origin. As a result, the pathology of the paraventricular lesions in ALS was confirmed to be different from that of the internal capsular lesions. (author).

  9. MRI of paraventricular white matter lesions in amyotrophic lateral sclerosis. Analysis by diffusion-weighted images

    International Nuclear Information System (INIS)

    Segawa, Fuminori; Kinoshita, Masao; Kishibayashi, Jun; Kamada, Kazuhiko; Sunohara, Nobuhiko.

    1994-01-01

    Magnetic resonance images in some cases of amyotrophic lateral sclerosis (ALS) revealed abnormal signals in both the paraventriculer white matter and in the posterior limbs of the internal capsule. We examined T 2 - and diffusion-weighted MR images of these lesions in 18 cases of ALS. There were symmetrical high-signal areas in the posterior limbs of the internal capsule in all of the cases. The high-signal areas in the internal capsule corresponded to the pyramidal tracts in the anatomical atlas by Talairach. In 5 of the cases of ALS, T 2 -weighted MR images showed discrete paraventricular white matter lesions as well. The mean age of the ALS patients with paraventricular white matter lesions was higher than that of the ALS patients without such lesions. Proton densities calculated from the conventional MR images were higher in both the capsular and paraventricular lesions. The diffusion coefficients perpendicular to the pyramidal tract in the internal capsular lesions were within the normal range, where as the diffusion coefficients in the paraventricular lesions were increased in all directions. Thus, diffusion anisotropy was lost in the paraventricular lesions. These findings are similar to those observed in the white matter lesions of cerebro-vascular origin. As a result, the pathology of the paraventricular lesions in ALS was confirmed to be different from that of the internal capsular lesions. (author)

  10. Evaluation of MR diffusion-weighted imaging in differentiating endometriosis infiltrating the bowel from colorectal carcinoma

    International Nuclear Information System (INIS)

    Busard, M.P.H.; Pieters-van den Bos, I.C.; Mijatovic, V.; Van Kuijk, C.; Bleeker, M.C.G.; Waesberghe, J.H.T.M. van

    2012-01-01

    Objective: Endometriosis infiltrating the bowel may be difficult to differentiate from colorectal carcinoma in cases that present with non-specific clinical and imaging features. The aim of this study is to assess the value of MR diffusion-weighted imaging (DWI) in differentiating endometriosis infiltrating the bowel from colorectal carcinoma. Methods: In 66 patients, MR DWI was added to the standard imaging protocol in patients visiting our outdoor MR clinic for the analysis of suspected or known deep infiltrating endometriosis (DIE). In patients diagnosed with DIE infiltrating the bowel on MR imaging, high b-value diffusion-weighted images were qualitatively assessed by two readers in consensus and compared to high b-value diffusion weighted images in 15 patients evaluated for colorectal carcinoma. In addition, ADC values of lesions were calculated, using b-values of 50, 400 and 800 s/mm 2 . Results: A total of 15 patients were diagnosed with DIE infiltrating the bowel on MR imaging. Endometriosis infiltrating the bowel showed low signal intensity on high b-value diffusion-weighted images in all patients, whereas colorectal carcinoma showed high signal intensity on high b-value diffusion-weighted images in all patients. Mean ADC value in endometriosis infiltrating the bowel (0.80 ± 0.06 × 10 −3 mm 2 /s) was significantly lower compared to mean ADC value in colorectal carcinoma (0.86 ± 0.06 × 10 −3 mm 2 /s), but with considerable overlap between ADC values. Conclusion: Only qualitative assessment of MR DWI may be valuable to facilitate differentiation between endometriosis infiltrating the bowel and colorectal carcinoma.

  11. Heroin-induced leukoencephalopathy: characterization using MRI, diffusion-weighted imaging, and MR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Offiah, C. [Department of Neuroradiology, St Bartholomew' s and the London Hospitals NHS Trust, London (United Kingdom); Hall, E. [Department of Neuroradiology, St Bartholomew' s and the London Hospitals NHS Trust, London (United Kingdom)], E-mail: curtis.offiah@bartsandthelondon.nhs.uk

    2008-02-15

    Aim: To describe the magnetic resonance imaging (MRI) characteristics of heroin-induced leukoencephalopathy or 'chasing the dragon syndrome' and, in particular, the diffusion-weighted imaging (DWI) and MR spectroscopy (MRS) features. Material and methods: Six patients with a clinical or histopathological diagnosis of heroin-induced leukoencephalopathy were identified and MRI examinations, including DWI and single-voxel MRS, reviewed. Results: Cerebellar white matter was involved in all six cases demonstrating similar symmetrical distribution with sparing of the dentate nuclei. Brain stem signal change was evident in five of the six patients imaged. Supratentorial brain parenchymal involvement, as well as brain stem involvement, correlated anatomically with corticospinal tract distribution. None of the areas of signal abnormality were restricted on DWI. Of those patients subjected to MRS, the areas of parenchymal damage demonstrated reduced N-acetylaspartate, reduced choline, and elevated lactate. Conclusion: Heroin-induced leukoencephalopathy results in characteristic and highly specific signal abnormalities on MRI, which can greatly aid diagnosis. DWI and MRS findings can be explained by known reported neuropathological descriptions in this condition and can be used to support a proposed mechanism for the benefit of current recommended drug treatment regimes.

  12. Chronic kidney disease: Pathological and functional evaluation with intravoxel incoherent motion diffusion-weighted imaging.

    Science.gov (United States)

    Mao, Wei; Zhou, Jianjun; Zeng, Mengsu; Ding, Yuqin; Qu, Lijie; Chen, Caizhong; Ding, Xiaoqiang; Wang, Yaqiong; Fu, Caixia

    2018-05-01

    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. To evaluate functional and pathological alterations in CKD by applying IVIM-DWI. Prospective study. In all, 72 CKD patients who required renal biopsy and 20 healthy volunteers. 1.5T. 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. One-way analysis of variance (ANOVA), paired sample t-test and Spearman correlation analysis. The paired sample t-test revealed that IVIM-DWI parameters were significantly lower in medulla than cortex for both patients and controls (P Imaging 2018;47:1251-1259. © 2017 International Society for Magnetic Resonance in Medicine.

  13. Diffusion-weighted imaging and the skeletal system: a literature review.

    Science.gov (United States)

    Yao, K; Troupis, J M

    2016-11-01

    Diffusion-weighted imaging (DWI) is a magnetic resonance imaging (MRI) sequence that has a well-established role in neuroimaging, and is increasingly being utilised in other clinical contexts, including the assessment of various skeletal disorders. It utilises the variability of Brownian motion of water molecules; the differing patterns of water molecular diffusion in various biological tissues help determine the contrast obtained in DWI. Although early research on the clinical role of DWI focused mainly on the field of neuroimaging, there are now more studies demonstrating the promising role DWI has in the diagnosis and monitoring of various osseous diseases. DWI has been shown to be useful in assessing a patient's skeletal tumour burden, monitoring the post-chemotherapy response of various bony malignancies, detecting hip ischaemia in patients with Legg-Calvé-Perthes disease, as well as determining the quality of repaired articular cartilage. Despite its relative successes, DWI has several limitations, including its limited clinical value in differentiating chondrosarcomas from benign bone lesions, as well as osteoporotic vertebral compression fractures from compression fractures due to malignancy. This literature review aims to provide an overview of the recent developments in the use of DWI in imaging the skeletal system, and to clarify the role of DWI in assessing various osseous diseases. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  14. Meduloblastoma: correlação entre ressonância magnética convencional, difusão e espectroscopia de prótons Medulloblastoma: correlation among findings of conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy

    Directory of Open Access Journals (Sweden)

    Mariana Vieira de Melo da Fonte

    2008-12-01

    Full Text Available OBJETIVO: Correlacionar os achados de ressonância magnética convencional, difusão e espectroscopia de prótons nos meduloblastomas, e compará-los aos dados da literatura. MATERIAIS E MÉTODOS: Análise retrospectiva de exames de ressonância magnética pré-operatórios de nove pacientes na faixa pediátrica com diagnóstico histológico de meduloblastoma (oito desmoplásicos e um de células gigantes. Foram considerados dados demográficos e características do tumor como localização, característica morfológica, intensidade de sinal, realce, disseminação e achados na difusão e espectroscopia. RESULTADOS: Na maioria dos casos os tumores apresentaram epicentro no vermis cerebelar (77,8%, sendo predominantemente sólido (88,9%, com hipossinal nas seqüências ponderadas em T1 e iso/hipersinal nas seqüências ponderadas em T2 e FLAIR, realce heterogêneo (100%, sinais de disseminação/extensão tumoral (77,8% e restrição à movimentação das moléculas de água (100%. A espectroscopia de prótons pela técnica STEAM (n = 6 demonstrou redução da relação Naa/Cr (83,3% e aumento de Co/Cr (100% e mI/Cr (66,7%, e pela técnica PRESS (n = 7 evidenciou pico de lactato (57,1%. CONCLUSÃO: O conjunto dos achados macroscópicos obtidos pela ressonância magnética, somado às características bioquímicas dos meduloblastomas, têm sido úteis na tentativa de diferenciação entre os principais tumores da fossa posterior.OBJECTIVE: To correlate imaging findings of medulloblastomas at conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy, comparing them with data in the literature. MATERIALS AND METHODS: Preoperative magnetic resonance imaging studies of nine pediatric patients with histologically confirmed medulloblastomas (eight desmoplastic medulloblastoma, and one giant cell medulloblastoma were retrospectively reviewed, considering demographics as well as tumors characteristics

  15. Diffusion-weighted MR imaging in benign and malignant orbital masses

    International Nuclear Information System (INIS)

    Guo Jian; Wang Zhenchang; Xian Junfang; Niu Yantao; Zhao Bo; Yan Fei; Liu Zhonglin; Yang Bentao

    2007-01-01

    Objective: To analyse the characteristics of orbital benign and malignant masses on diffusion weighted imaging in combination with conventional MR imaging and evaluate the diagnostic value of apparent diffusion coefficient in distinguishing benign and malignant orbital lesions. Methods: Seventy- seven cases with orbital masses, including fifty-five benign lesions and twenty-two malignant tumors, who underwent conventional MRI and diffusion imaging scanning were studied with use of a 1.5 T magnetic resonance system. Quantitative ADC measurements of masses (ADCM) and of the white matter of contralateral temporal lobe (ADC w ) were made with two different b-values of 0 and 1000 s/mm 2 . The ADC ratio (ADCR) of the lesion to the control was calculated. The receiver operating characteristic curves(ROC) were constructed using various cut points of ADCM and ADCR for different parameters to differentiate between benign and malignant masses. The area under the ROC curve for each parameter was also calculated. Results: All cases were proved by histopathology. The mean ADCM and ADCR of benign orbital masses were (1.56 ± 0.75) x 10 -3 mm 2 /s and 1.85 ± 0.91, respectively. The mean ADCM and ADCR of malignant orbital masses were (1.09 ± 0.42) x 10 -3 mm 2 /s and 1.28 ± 0.53, respectively. There were significant difference both between ADCM and ADCR of benign and malignant masses (t=2.803, 2.735, P -3 mm 2 /s for ADC M of the tumor, the sensitivity, specificity and accuracy were 59.1%, 78.2% and 72.7%, respectively. And by using cut point of 1.24 for ADCR, the sensitivity, specificity and accuracy were 59.1%, 76.4%, 71.4%, respectively. Conclusion: Diffusion MR imaging and ADC value could provide additional information for conventional magnetic resonance imaging in distinguishing benign and malignant orbital masses. (authors)

  16. The research on distinguishing benign from malignant breast lesions by diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Zhao Bin; Peng Hongjuan; Cai Shifeng; Gao Peihong

    2005-01-01

    Objective: To investigate the value of apparent diffusion coefficient (ADC) of diffusion- weighted magnetic resonance imaging (DW-MRI) in distinguishing benign from malignant breast lesions. Methods: ADC in 26 normal breasts, 24 malignant breast lesions, and 30 benign breast lesions confirmed by operation and pathology were calculated, respectively, and their differentiations in statistics were compared. The differentiations of different ADCs (b=1000-0, 500-0, 1000-500 s/mm 2 ) were also compared. EPI (TR 2900 ms, TE 84 ms, thickness 5 mm) was used in order to acquire the imaging. Results: There were significant differences among the ADC values of normal breast tissue, benign, and malignant lesions. The ADC of malignant lesions was lower than those of normal breast tissue and benign lesions, and the ADC of benign lesions was lower than that of normal breast tissue. There were significant differences among the ADC value of b=1000-0, 1000-500, and 500-0 s/mm 2 . The lower the b value, the higher the ADC. The sensitivity and specificity of ADC for the diagnosis of malignant lesion were 64% and 96.7% if the upper bound of 95% confidence interval was set as a differential level. Conclusion: The differentiation of benign from malignant breast lesions by ADC is applicable, although the sensitivity is low, the specificity is high. (authors)

  17. Intravoxel Incoherent Motion Diffusion-weighted Imaging: Evaluation of the Differentiation of Solid Hepatic Lesions

    Directory of Open Access Journals (Sweden)

    Ma Luo

    2017-10-01

    Full Text Available PURPOSE: To evaluate whether intravoxel incoherent motion (IVIM–related parameters could be used to differentiate malignant from benign focal liver lesions (FLLs and to improve diagnostic efficiency. METHODS: Seventy-four patients with 75 lesions, including 51 malignant FLLs and 24 benign FLLs, underwent liver 3.0-T magnetic resonance imaging for routine examination sequences. IVIM diffusion-weighted imaging (DWI with 11 b values (0-800 s/mm2 was also acquired concurrently. Apparent diffusion coefficient (ADCtotal and IVIM-derived parameters, such as the pure diffusion coefficient (D, the pseudodiffusion coefficient (D⁎, and the perfusion fraction (f, were calculated and compared between the two groups. A receiver operating characteristic curve analysis was performed to assess their diagnostic value. RESULTS: ADCtotal, D, and f were significantly lower in the malignant group than in the benign group, whereas D⁎ did not show a statistical difference. D had a larger area under the curve value (0.968 and higher sensitivity (92.30% for differentiation. CONCLUSION: IVIM is a useful method to differentiate malignant and benign FLLs. The D value showed higher efficacy to detect hepatic solid lesions.

  18. Human cerebral cortices: signal variation on diffusion-weighted MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Asao, Chiaki [Kumamoto Regional Medical Center, Department of Radiology, Kumamoto (Japan); National Hospital Organization Kumamoto Medical Center, Department of Radiology, Kumamoto (Japan); Hirai, Toshinori; Yamashita, Yasuyuki [Kumamoto University Graduate School of Medical Sciences, Department of Diagnostic Radiology, Kumamoto (Japan); Yoshimatsu, Shunji [National Hospital Organization Kumamoto Medical Center, Department of Radiology, Kumamoto (Japan); Matsukawa, Tetsuya; Imuta, Masanori [Kumamoto Regional Medical Center, Department of Radiology, Kumamoto (Japan); Sagara, Katsuro [Kumamoto Regional Medical Center, Department of Internal Medicine, Kumamoto (Japan)

    2008-03-15

    We have often encountered high signal intensity (SI) of the cingulate gyrus and insula during diffusion-weighted magnetic resonance imaging (DW-MRI) on neurologically healthy adults. To date, cortical signal heterogeneity on DW images has not been investigated systematically. The purpose of our study was to determine whether there is regional signal variation in the brain cortices of neurologically healthy adults on DW-MR images. The SI of the cerebral cortices on DW-MR images at 1.5 T was evaluated in 50 neurologically healthy subjects (34 men, 16 women; age range 33-84 years; mean age 57.6 years). The cortical SI in the cingulate gyrus, insula, and temporal, occipital, and parietal lobes was graded relative to the SI of the frontal lobe. Contrast-to-noise ratios (CNRs) on DW-MR images were compared for each cortical area. Diffusion changes were analyzed by visually assessment of the differences in appearance among the cortices on apparent diffusion coefficient (ADC) maps. Increased SI was frequently seen in the cingulate gyrus and insula regardless of patient age. There were no significant gender- or laterality-related differences. The CNR was significantly higher in the cingulate gyrus and insula than in the other cortices (p <.01), and significant differences existed among the cortical regions (p <.001). There were no apparent ADC differences among the cortices on ADC maps. Regional signal variation of the brain cortices was observed on DW-MR images of healthy subjects, and the cingulate gyrus and insula frequently manifested high SI. These findings may help in the recognition of cortical signal abnormalities as visualized on DW-MR images. (orig.)

  19. Human cerebral cortices: signal variation on diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Asao, Chiaki; Hirai, Toshinori; Yamashita, Yasuyuki; Yoshimatsu, Shunji; Matsukawa, Tetsuya; Imuta, Masanori; Sagara, Katsuro

    2008-01-01

    We have often encountered high signal intensity (SI) of the cingulate gyrus and insula during diffusion-weighted magnetic resonance imaging (DW-MRI) on neurologically healthy adults. To date, cortical signal heterogeneity on DW images has not been investigated systematically. The purpose of our study was to determine whether there is regional signal variation in the brain cortices of neurologically healthy adults on DW-MR images. The SI of the cerebral cortices on DW-MR images at 1.5 T was evaluated in 50 neurologically healthy subjects (34 men, 16 women; age range 33-84 years; mean age 57.6 years). The cortical SI in the cingulate gyrus, insula, and temporal, occipital, and parietal lobes was graded relative to the SI of the frontal lobe. Contrast-to-noise ratios (CNRs) on DW-MR images were compared for each cortical area. Diffusion changes were analyzed by visually assessment of the differences in appearance among the cortices on apparent diffusion coefficient (ADC) maps. Increased SI was frequently seen in the cingulate gyrus and insula regardless of patient age. There were no significant gender- or laterality-related differences. The CNR was significantly higher in the cingulate gyrus and insula than in the other cortices (p <.01), and significant differences existed among the cortical regions (p <.001). There were no apparent ADC differences among the cortices on ADC maps. Regional signal variation of the brain cortices was observed on DW-MR images of healthy subjects, and the cingulate gyrus and insula frequently manifested high SI. These findings may help in the recognition of cortical signal abnormalities as visualized on DW-MR images. (orig.)

  20. Pediatric littoral cell angioma of the spleen: multimodality imaging including diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ertan, Gulhan; Tekes, Aylin; Huisman, Thierry A.G.M. [Johns Hopkins Hospital, Division of Pediatric Radiology, Department of Radiology and Radiological Science, Baltimore, MD (United States); Mitchell, Sally [Johns Hopkins Hospital, Division of Cardiovascular and Interventional Radiology, Department of Radiology and Radiological Science, Baltimore (United States); Keefer, Jeffrey [Johns Hopkins Hospital, Division of Pediatric Hematology, Department of Pediatrics, Baltimore, MD (United States)

    2009-10-15

    Littoral cell angioma (LCA) is a rare primary splenic vascular tumor originating from littoral cells lining the splenic red pulp sinuses. LCAs are rarely seen in children. We present the US, CT, and MRI findings including diffusion-weighted imaging (DWI) in a 2-year-old boy with histologically proven LCA. Previous studies on liver lesions have shown that DWI allows differentiation of vascular tumors from primary neoplasms and metastatic disease. The current case indicates that increased ADC values within the splenic lesions suggest a vascular etiology, which might help narrow the differential diagnosis. (orig.)

  1. Pediatric littoral cell angioma of the spleen: multimodality imaging including diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Ertan, Gulhan; Tekes, Aylin; Huisman, Thierry A.G.M.; Mitchell, Sally; Keefer, Jeffrey

    2009-01-01

    Littoral cell angioma (LCA) is a rare primary splenic vascular tumor originating from littoral cells lining the splenic red pulp sinuses. LCAs are rarely seen in children. We present the US, CT, and MRI findings including diffusion-weighted imaging (DWI) in a 2-year-old boy with histologically proven LCA. Previous studies on liver lesions have shown that DWI allows differentiation of vascular tumors from primary neoplasms and metastatic disease. The current case indicates that increased ADC values within the splenic lesions suggest a vascular etiology, which might help narrow the differential diagnosis. (orig.)

  2. MR imaging of primary sclerosing cholangitis - Additional value of diffusion-weighted imaging and ADC measurement

    Energy Technology Data Exchange (ETDEWEB)

    Djokicc Kovac, Jelena [Center for Radiology and Magnetic Resonance Imaging, Clinical Center Serbia, Belgrade (Serbia)], e-mail: jelenadjokic2003@yahoo.co.uk; Maksimovic, Ruzica [Center for Radiology and Magnetic Resonance Imaging, Clinical Center Serbia, Belgrade (Serbia); Faculty of Medicine, Univ. of Belgrade, Belgrade (Serbia); Jesic, Rada [Clinic for Gastroenterohepatology, Clinical Center Serbia, Belgrade (Serbia); Faculty of Medicine, Univ. of Belgrade, Belgrade (Serbia); Stanisavljevic, Dejana [Inst. for Statistics, Faculty of Medicine, Univ. of Belgrade, Belgrade (Serbia); Kovac, Bojan [Military Medical Academy, Belgrade (Serbia)

    2013-04-15

    Background: Primary sclerosing cholangitis (PSC) is a cholestatic liver disease with chronic inflammation and progressive destruction of biliary tree. Magnetic resonance (MR) examination with diffusion-weighted imaging (DWI) allows analysis of morphological liver parenchymal changes and non-invasive assessment of liver fibrosis. Moreover, MR cholangiopancreatography (MRCP), as a part of standard MR protocol, provides insight into bile duct irregularities. Purpose: To evaluate MR and MRCP findings in patients with primary sclerosing cholangitis and to determine the value of DWI in the assessment of liver fibrosis. Material and Methods: The following MR findings were reviewed in 38 patients: abnormalities in liver parenchyma signal intensity, changes in liver morphology, lymphadenopathy, signs of portal hypertension, and irregularities of intra- and extrahepatic bile ducts. Apparent diffusion coefficient (ADC) was calculated for six locations in the liver for b = 800 s/mm{sup 2}. Results: T2-weighted hyperintensity was seen as peripheral wedge-shaped areas in 42.1% and as periportal edema in 28.9% of patients. Increased enhancement of liver parenchyma on arterial-phase imaging was observed in six (15.8%) patients. Caudate lobe hypertrophy was present in 10 (26.3%), while spherical liver shape was noted in 7.9% of patients. Liver cirrhosis was seen in 34.2% of patients; the most common pattern was micronodular cirrhosis (61.5%). Other findings included lymphadenopathy (28.9%), signs of portal hypertension (36.7%), and bile duct irregularities (78.9%). The mean ADCs (x10{sup -3} mm{sup 2}/s) were significantly different at stage I vs. stages III and IV, and stage II vs. stage IV. No significant difference was found between stages II and III. For prediction of stage {>=}II and stage {>=}III, areas under receiver-operating characteristic curves were 0.891 and 0.887, respectively. Conclusion: MR with MRCP is a necessary diagnostic procedure for diagnosis of PSC and

  3. Fat-saturated diffusion-weighted imaging with three-dimensional MP-RAGE sequence

    International Nuclear Information System (INIS)

    Numano, Tomokazu; Homma, Kazuhiro; Takahashi, Nobuyuki; Hirose, Takeshi

    2005-01-01

    Image misrepresentation due to chemical shifts can create image artifacts on MR images. Distinguishing the organization and affected area can be difficult due to the chemical shift artifacts. Chemical shift selective (CHESS) is a method of decreasing chemical shift artifacts. In this study we have developed a new sequence for fat-saturated three-dimensional diffusion weighted MR imaging. This imaging was done during in vivo studies using an animal experiment MR imaging system at 2.0 T. In this sequence a preparation phase with a ''CHESS-90 deg RF-Motion Proving Gradient (MPG-180 deg RF-MPG-90 deg RF pulse train) was used to sensitize the magnetization to fat-saturated diffusion. Centric k-space acquisition order is necessary to minimize saturation effects from tissues with short relaxation times. From experimental results obtained with a phantom, the effect of the diffusion weighting and the effect of the fat-saturation were confirmed. From rat experimental results, fat-saturated diffusion weighted image data (0.55 x 0.55 x 0.55 mm 3 : voxel size) were obtained. This sequence was useful for in vivo imaging. (author)

  4. The role of diffusion weighted MR imaging for differentiation between Graves' disease and Hashimoto thyroiditis.

    Science.gov (United States)

    Ozturk, T; Bozgeyik, Z; Ozturk, F; Burakgazi, G; Akyol, M; Coskun, S; Ozkan, Y; Ogur, E

    2015-08-01

    The aim of this study was to evaluate the usefulness of diffusion-weighted magnetic resonance imaging (DWMRI) for differentation between Graves' disease and Hashimoto's thyroiditis. Fifty patients (27 Graves diseases and 23 Hashimoto thyroiditis) and twenty healthy volunteers were examined using T1, T2 and DWMRI. The patients were diagnosed on the basis of physical findings and the results of thyroid function tests and serological tests. Circular ROIs were positioned on the bilateral thyroid lobes and isthmus. All measurements were repeated three different b values including 100, 600 and 1000 s/mm2 in all cases. ADC (Apparent diffusion coefficient) maps were calculated automatically with the MR system. Mean ADC values were 2.93 × 10-3, 1.97 × 10-3 and 1.62 × 10-3 mm2/s in the healthy volunteers; 3.47 × 10-3, 2.25 × 10-3 and 1.64 × 10-3 mm2/s in Graves' disease; 2.53 × 10-3, 1.76 × 10-3, 1.28 × 10-3 mm2/s in Hashimoto thyroiditis for b100, b600 and b1000, respectively. The ADC values of the Graves diseases were higher than healty volunteers and Hashimoto thyroiditis. ADC values were statistically significant for differentation between Hashimoto thyroiditis and Graves' disease all b values (p Hashimoto thyroiditis and Graves' disease.

  5. Diffusion-weighted MR imaging of salivary glands with gustatory stimulation - Comparison before and after radiotherapy

    International Nuclear Information System (INIS)

    Zhang, Yunyan; Gu, Yajia; Peng, Weijun; Mao, Jian; Lei, Yue; Shen, Xigang; Ou, Dan; He, Xiayun

    2013-01-01

    Background: Xerostomia is the most prominent complication in patients with head and neck carcinoma after radiotherapy (RT). Diffusion-weighted magnetic resonance imaging (DWI) with gustatory stimulation may contribute to the evaluation of salivary gland function. Purpose: To investigate the value of DWI for quantifying physiological changes of the parotid gland during gustatory stimulation in patients before and after RT. Material and Methods: Magnetic resonance imaging (MRI) was performed in 28 consecutive patients with nasopharyngeal carcinoma before and after RT and clinical xerostomia was also assessed. A DWI sequence was performed once at rest and continually repeated seven times during stimulation with ascorbic acid. Apparent diffusion coefficient (ADC) maps for parotid glands at different time points and the range of increase with stimulation were calculated. Paired two-tailed Student t tests were used to compare the ADC values before and after stimulation, and before and after RT. Results: Before RT, the ADC showed an initial increase (P<0.001) and then fluctuated during stimulation. After RT, as the clinical xerostomia changed from Grade 0 to Grade 2, the mean ADC at rest increased compared with the pre-RT value (P<0.001). A similar response to stimulation was observed, but the range of increase between the maximum ADC during stimulation and the baseline value at rest was higher post-RT than pre-RT (P=0.022). The minimum ADC during stimulation was higher than the baseline value post-RT (P=0.028), but there was no difference pre-RT (P=0.603). Conclusion: DWI combined with gustatory stimulation seems to display the physiological changes of the parotid gland following RT and may be a potential tool for non-invasively assessing salivary gland function

  6. Diffusion-weighted MR imaging of salivary glands with gustatory stimulation - Comparison before and after radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yunyan; Gu, Yajia; Peng, Weijun; Mao, Jian; Lei, Yue; Shen, Xigang [Dept. of Radiology, Fudan Univ. Shanghai Cancer Center, Shanghai (China); Dept. of Oncology, Shanghai Medical College, Fudan Univ., Shanghai (China); Ou, Dan; He, Xiayun [Dept. of Radiation Oncology, Fudan Univ. Shanghai Cancer Center, Shanghai (China); Dept. of Oncology, Shanghai Medical College, Fudan Univ., Shanghai (China)

    2013-10-15

    Background: Xerostomia is the most prominent complication in patients with head and neck carcinoma after radiotherapy (RT). Diffusion-weighted magnetic resonance imaging (DWI) with gustatory stimulation may contribute to the evaluation of salivary gland function. Purpose: To investigate the value of DWI for quantifying physiological changes of the parotid gland during gustatory stimulation in patients before and after RT. Material and Methods: Magnetic resonance imaging (MRI) was performed in 28 consecutive patients with nasopharyngeal carcinoma before and after RT and clinical xerostomia was also assessed. A DWI sequence was performed once at rest and continually repeated seven times during stimulation with ascorbic acid. Apparent diffusion coefficient (ADC) maps for parotid glands at different time points and the range of increase with stimulation were calculated. Paired two-tailed Student t tests were used to compare the ADC values before and after stimulation, and before and after RT. Results: Before RT, the ADC showed an initial increase (P<0.001) and then fluctuated during stimulation. After RT, as the clinical xerostomia changed from Grade 0 to Grade 2, the mean ADC at rest increased compared with the pre-RT value (P<0.001). A similar response to stimulation was observed, but the range of increase between the maximum ADC during stimulation and the baseline value at rest was higher post-RT than pre-RT (P=0.022). The minimum ADC during stimulation was higher than the baseline value post-RT (P=0.028), but there was no difference pre-RT (P=0.603). Conclusion: DWI combined with gustatory stimulation seems to display the physiological changes of the parotid gland following RT and may be a potential tool for non-invasively assessing salivary gland function.

  7. Diffusion-weighted magnetic resonance imaging of thymoma: ability of the Apparent Diffusion Coefficient in predicting the World Health Organization (WHO) classification and the Masaoka-Koga staging system and its prognostic significance on disease-free survival

    International Nuclear Information System (INIS)

    Priola, Adriano Massimiliano; Priola, Sandro Massimo; Gned, Dario; Ducco, Lorena; Veltri, Andrea; Giraudo, Maria Teresa; Fornari, Alessandro; Ferrero, Bruno

    2016-01-01

    To evaluate the usefulness of diffusion-weighted magnetic resonance for distinguishing thymomas according to WHO and Masaoka-Koga classifications and in predicting disease-free survival (DFS) by using the apparent diffusion coefficient (ADC). Forty-one patients were grouped based on WHO (low-risk vs. high-risk) and Masaoka-Koga (early vs. advanced) classifications. For prognosis, seven patients with recurrence at follow-up were grouped separately from healthy subjects. Differences on ADC levels between groups were tested using Student-t testing. Logistic regression models and areas under the ROC curve (AUROC) were estimated. Mean ADC values were different between groups of WHO (low-risk = 1.58 ± 0.20 x 10 -3 mm 2 /sec; high-risk = 1.21 ± 0.23 x 10 -3 mm 2 /sec; p < 0.0001) and Masaoka-Koga (early = 1.43 ± 0.26 x 10 -3 mm 2 /sec; advanced = 1.31 ± 0.31 x 10 -3 mm 2 /sec; p = 0.016) classifications. Mean ADC of type-B3 (1.05 ± 0.17 x 10 -3 mm 2 /sec) was lower than type-B2 (1.32 ± 0.20 x 10 -3 mm 2 /sec; p = 0.023). AUROC in discriminating groups was 0.864 for WHO classification (cut-point = 1.309 x 10 -3 mm 2 /sec; accuracy = 78.1 %) and 0.730 for Masaoka-Koga classification (cut-point = 1.243 x 10 -3 mm 2 /sec; accuracy = 73.2 %). Logistic regression models and two-way ANOVA were significant for WHO classification (odds ratio[OR] = 0.93, p = 0.007; p < 0.001), but not for Masaoka-Koga classification (OR = 0.98, p = 0.31; p = 0.38). ADC levels were significantly associated with DFS recurrence rate being higher for patients with ADC ≤ 1.299 x 10 -3 mm 2 /sec (p = 0.001; AUROC, 0.834; accuracy = 78.0 %). ADC helps to differentiate high-risk from low-risk thymomas and discriminates the more aggressive type-B3. Primary tumour ADC is a prognostic indicator of recurrence. (orig.)

  8. Capabilities of diffusion-weighted and fresh blood imaging in depicting fresh thrombus. Presidential award proceedings

    International Nuclear Information System (INIS)

    Ando, Ritsuko; Manabe, Tsutomu; Tazawa, Satoru

    2007-01-01

    We examined the capabilities of diffusion-weighted (DWI) and fresh-blood imaging (FBI) in depicting thrombus. A paper-clay phantom holding test syringes of various sizes filled with either contrast medium or fresh human blood were scanned using a 1.5T magnetic resonance (MR) imaging unit, and apparent diffusion coefficient (ADC) values and signal intensities on DWI and FBI of the specimens were obtained. FBI depicted all the specimens regardless of syringe diameter, but DWI failed to image the syringe measuring 0.5 cm in diameter. B-factors and/or number of acquisitions (NAQ) seemed responsible for DWI's depiction capability. ADC values and signal intensities on DWI and FBI correlated with the viscosity of the contrast medium samples. Clotted blood, the most viscous of the samples, had the smallest ADC value and no relationship with signal intensities on DWI and FBI. Larger b-factors reduced signal intensity in contrast medium on DWI, but signals decreased only minimally in clotted blood. The result suggested that although viscosity was the influential factor for signal intensities on DWI in contrast medium, other factors, such as particle sizes of fibrin and hemoglobin, accounted for the low ADC values in clotting blood. T 2 relaxation time seemed to play a significant role in making signal intensities on DWI irrelevant to b-factors. Despite lapsed time, the clots were persistently hyperintense on FBI with a tendency to decrease only gradually. On DWI, there was a certain period when signal intensities were high and ADC values were low. The signal intensities on DWI and ADC values were considered to be influenced by the process of clot formation, and disappearance of signal seemed likely attributable to degeneration of protein and organization of the clot. (author)

  9. Diffusion-weighted imaging and diffusion tensor imaging of asymptomatic lumbar disc herniation.

    Science.gov (United States)

    Sakai, Toshinori; Miyagi, Ryo; Yamabe, Eiko; Fujinaga, Yasunari; N Bhatia, Nitin; Yoshioka, Hiroshi

    2014-01-01

    Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) were performed on a healthy 31-year-old man with asymptomatic lumbar disc herniation. Although the left S1 nerve root was obviously entrapped by a herniated mass, neither DWI nor DTI showed any significant findings for the nerve root. Decreased apparent diffusion coefficient (ADC) values and increased fractional anisotropy (FA) values were found. These results are contrary to those in previously published studies of symptomatic patients, in which a combination of increased ADC and decreased FA seem to have a relationship with nerve injury and subsequent symptoms, such as leg pain or palsy. Our results seen in an asymptomatic subject suggest that the compressed nerve with no injury, such as edema, demyelination, or persistent axonal injury, may be indicated by a combination of decreased ADC and increased FA. ADC and FA could therefore be potential tools to elucidate the pathomechanism of radiculopathy.

  10. Functional imaging of submandibular glands: diffusion-weighted echo-planar MRI before and after stimulation

    International Nuclear Information System (INIS)

    Arndt, C.; Cramer, M.C.; Weiss, F.; Kaul, M.G.; Adam, G.; Habermann, C.R.; Graessner, J.; Petersen, K.; Reitmeier, F.; Jaehne, M.

    2006-01-01

    Purpose: To investigate the feasibility of diffusion-weighted (DWI) echo-planar imaging (EPI) to depict the submandibular glands and to measure different functional conditions. Materials and Methods: Twenty-seven healthy volunteers were examined. Diffusion weighted sequence was performed prior to stimulation. Exactly 30 seconds after a commercially available lemon juice was given orally, the diffusion weighted sequence was repeated. All examinations were performed by using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and maximum slew rate of 125 mT/m/sec (Magnetom Symphony, Siemens, Erlangen, Germany). The lower part of the circularly polarized (CP) head coil and a standard two-element CP neck array coil were used. The flexibility of the neck array coil allowed positioning the N1 element (upper part of the coil) right next to the submandibular gland. The axial diffusion-weighted EPI (echo planar imaging) sequence was performed using a matrix of 119 x 128, a field of view of 250 x 250 mm (pixel size 2.1 x 1.95 mm), a section thickness of 5 mm with an interslice gap of 1 mm. The b factors used were 0 sec/mm 2 , 500 sec/mm 2 and 1000 sec/mm 2 . Apparent diffusion coefficient (ADC) maps were digitally transferred to MRIcro (Chris Rorden, University of Nottingham, Great Britain). After detecting the submandibular glands a region of interest (ROI) was placed manually exactly within the boarder of both submandibular glands, excluding the external carotid artery on ADC maps. These procedures were performed on all ADC slices the submandibular glands could be differentiated in before and after oral stimulation. For statistical comparison of results, a student's t-test was performed with an overall two-tailed significance level of p=0.05. Results: The visualization of the submandibular glands using the diffusion-weighted EPI sequence was possible in all of the 27 volunteers. Prior to oral stimulation an ADC of 1.31 x 10 -3 mm 2 /sec (95% CI, 1

  11. Diffusion-weighted imaging in diagnosing neurological disorders in children: a pediatric neurologist's perspective

    International Nuclear Information System (INIS)

    Benedict, Susan L.

    2007-01-01

    Diffusion-weighted imaging (DWI) has provided a way to measure early changes in cellular function in the central nervous system. It has permitted rapid, less invasive diagnosis and treatment of neurological disorders that were once thought to be untreatable. DWI has also created new avenues of research and alternative ways to measure study outcomes. Seven clinical cases illustrate how DWI enhances the ability of the pediatric neurologist to rapidly diagnose acute neurological disorders in infants and children. (orig.)

  12. Diffusion-weighted imaging of tumor recurrencies and posttherapeutical soft-tissue changes in humans

    International Nuclear Information System (INIS)

    Baur, A.; Huber, A.; Reiser, M.; Arbogast, S.; Duerr, H.R.; Zysk, S.; Wendtner, C.; Deimling, M.

    2001-01-01

    The aim of this study was to examine soft tissue tumor recurrences and posttherapeutic soft tissue changes in humans with a diffusion-weighted steady-state free precession (SSFP) sequence. Twenty-four patients with 29 pathologies of the pelvis or the extremities were examined. The lesions were classified as follows: group 1, recurrent viable tumors (n = 10); group 2, postoperative hygromas (n = 7); and group 3, posttherapeutic reactive inflammatory muscle changes (n = 12). The sequence protocol in these patients consisted of short tau inversion recovery images, T2-weighted spin-echo (SE), pre- and postcontrast T1-weighted SE images and the diffusion-weighted SSFP sequence. The signal loss on diffusion-weighting was evaluated visually on a four-grade scale and quantitatively. The signal intensities were measured in regions of interest and a regression analysis was performed. Statistical analyses was performed utilizing the Student's t-test. The signal loss was significantly higher for hygromas and edematous muscle changes than for recurrent tumors (p < 0.001) indicating higher diffusion of water protons. The regression coefficient was -0.11 (mean) for tumors. Hygromas had a significantly higher signal loss than inflammatory edematous muscle changes (p < 0.01). The regression coefficients were -0.29 (mean) for hygromas and -0.22 (mean) for edematous muscle changes. The SSFP sequence seems to be a suitable method for diffusion-weighted imaging of the musculoskeletal system in humans. These preliminary results suggest that the signal loss and the regression coefficients can be used to characterize different types of tissue. (orig.)

  13. Can MRI diffusion-weighted imaging identify postoperative residual/recurrent soft-tissue sarcomas?

    Directory of Open Access Journals (Sweden)

    Mai Maher ElDaly

    2018-01-01

    Full Text Available Purpose: The aim of this study was to evaluate contrast-enhanced magnetic resonance imaging (CE-MRI and quantitative diffusion-weighted imaging (DWI with apparent diffusion coefficient (ADC mapping in the detection of recurrent/residual postoperative soft tissue sarcomas. Materials and Methods: This study included 36 patients; 27 patients had postoperative recurrent/residual soft tissue sarcomas and 9 patients had postoperative and treatment-related changes (inflammation/fibrosis. The DWI was obtained with 3 b values including 0, 400, and 800 s/mm2. Calculation of the ADC value of the lesion was done via placing the region of interest (ROI to include the largest area of the lesion. ADC values were compared to histopathology. Results: Our results showed that including CE-MRI improved the diagnostic accuracy and sensitivity in recurrence detection compared to conventional non-enhanced sequences. However, it showed low specificity (55.56% with a high false-positive rate that may lead to an unnecessary biopsy of a mass such as region of postoperative scar tissue. Conclusion: The joint use of gadolinium-enhanced MRI and quantitative DWI with ADC mapping offer added value in the detection of recurrent/residual postoperative soft tissue sarcoma. This combined use increased both the diagnostic sensitivity and specificity with a cut-off average ADC value for detecting nonmyxoid recurrent/residual lesions ≤1.3 × 10−3 mm2/s (100% specificity and 90.48% sensitivity. Our results showed limited value of DWI with ADC mapping in assessing myxoid sarcomatous tumor recurrences.

  14. Diffusion-weighted MR images and pineoblastoma. Diagnosis and follow-up

    International Nuclear Information System (INIS)

    Gasparetto, Emerson L.; Cruz Junior, L. Celso Hygino; Doring, Thomas M.; Domingues, Romeu C.; Araujo, Bertha; Dantas, Mario Alberto; Chimelli, Leila

    2008-01-01

    Pineoblastomas are uncommon pineal tumors, which demonstrate rapid growing and poor prognosis. We report the case of a 43-year-old man with an enhancing pineal region mass, which showed restriction of the diffusion on diffusion-weighted (DW) MR images. The surgical biopsy defined the diagnosis of pineoblastoma and the therapy was initiated with radiation and chemotherapy. Three months later, the follow-up MR imaging showed areas suggestive of necrosis and the DW images demonstrate no significant areas of restricted diffusion. The differential diagnosis of pineal region masses that could show restriction of diffusion is discussed. (author)

  15. The correlation between biological activity and diffusion-weighted MR imaging and ADC value in cases with prostate cancer.

    Science.gov (United States)

    Sokmen, Bedriye Koyuncu; Sokmen, Dogukan; Ucar, Nese; Ozkurt, Huseyin; Simsek, Abdulmuttalip

    2017-12-31

    Firstly, we aimed to investigate the correlation among dynamic contrasted magnetic resonance (MR) images, diffusion-weighted MR images, and apparent diffusion coefficent (ADC) values in patients with prostate cancer. Secondly, we aimed to investigate the roles of these variables on clinical risk classification and the biological behavior of the prostate cancer. A total of sixty with prostatic adenocarcinoma patients diagnosed between January 2011 and May 2013 were retrospectively included in the study. Risk classification of patients were evaluated as low-risk (Group 1) (n = 20) (Stage T1c-T2a, PSA T3a, PSA > 20 ng/ml, Gleason Score > 7). Diffusion-weighted MR images, dynamic contrasted MR images, and ADC values of the prostates were correlated. ADC values of the cases in Group 3 were lower than those of the other groups (p values of the areas without malignancy did not differ significantly between groups (p > 0.05). Biological activity of the tumor tissue was determined by GS, while a negative correlation was observed between GSs and ADC values of the patients, (p values were obtained. These measured values can play a role in the noninvasive determination of the cellularity of the tumoral mass.

  16. MR tractography; Visualization of structure of nerve fiber system from diffusion weighted images with maximum intensity projection method

    Energy Technology Data Exchange (ETDEWEB)

    Kinosada, Yasutomi; Okuda, Yasuyuki (Mie Univ., Tsu (Japan). School of Medicine); Ono, Mototsugu (and others)

    1993-02-01

    We developed a new noninvasive technique to visualize the anatomical structure of the nerve fiber system in vivo, and named this technique magnetic resonance (MR) tractography and the acquired image an MR tractogram. MR tractography has two steps. One is to obtain diffusion-weighted images sensitized along axes appropriate for depicting the intended nerve fibers with anisotropic water diffusion MR imaging. The other is to extract the anatomical structure of the nerve fiber system from a series of diffusion-weighted images by the maximum intensity projection method. To examine the clinical usefulness of the proposed technique, many contiguous, thin (3 mm) coronal two-dimensional sections of the brain were acquired sequentially in normal volunteers and selected patients with paralyses, on a 1.5 Tesla MR system (Signa, GE) with an ECG-gated Stejskal-Tanner pulse sequence. The structure of the nerve fiber system of normal volunteers was almost the same as the anatomy. The tractograms of patients with paralyses clearly showed the degeneration of nerve fibers and were correlated with clinical symptoms. MR tractography showed great promise for the study of neuroanatomy and neuroradiology. (author).

  17. The correlation between biological activity and diffusion-weighted MR imaging and ADC value in cases with prostate cancer

    Directory of Open Access Journals (Sweden)

    Bedriye Koyuncu Sokmen

    2017-12-01

    Full Text Available Purpose: Firstly, we aimed to investigate the correlation among dynamic contrasted magnetic resonance (MR images, diffusion-weighted MR images, and apparent diffusion coefficent (ADC values in patients with prostate cancer. Secondly, we aimed to investigate the roles of these variables on clinical risk classification and the biological behavior of the prostate cancer. Methods: A total of sixty with prostatic adenocarcinoma patients diagnosed between January 2011 and May 2013 were retrospectively included in the study. Risk classification of patients were evaluated as low-risk (Group 1 (n = 20 (Stage T1c-T2a, PSA T3a, PSA > 20 ng/ml, Gleason Score > 7. Diffusion-weighted MR images, dynamic contrasted MR images, and ADC values of the prostates were correlated. Results: ADC values of the cases in Group 3 were lower than those of the other groups (p 0.05. Biological activity of the tumor tissue was determined by GS, while a negative correlation was observed between GSs and ADC values of the patients, (p < 0.001. Conclusion: In tumors with higher Gleason scores, lower ADC values were obtained. These measured values can play a role in the noninvasive determination of the cellularity of the tumoral mass.

  18. Intraparenchymal epidermoid cysts in the brain: diagnostic value of MR diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hu, X.-Y. [Medical Imaging Center, The First Affiliated Hospital of Suzhou, Jiangsu Province (China); Hu, C.-H. [Imaging Center, Soochow University (China)], E-mail: wpdrhxy@hotmail.com; Fang, X.-M.; Cui, L.; Zhang, Q.-H. [Medical Imaging Center, The First Affiliated Hospital of Suzhou, Jiangsu Province (China)

    2008-07-15

    Aim: To evaluate the value of magnetic resonance (MR) diffusion-weighted imaging (DWI) and apparent diffusion coefficients (ADC) maps in the diagnosis of intraparenchymal epidermoid cysts (ECs). Materials and methods: Six cases of histopathologically proven intraparenchymal ECs were studied. All patients were examined with conventional MR (T1WI, T2WI, contrast-enhanced T1WI) and DWI sequences. Along with the mean ADC values (mADC) of the ECs, the cerebrospinal fluid (CSF) and grey matter (GM) were measured. Qualitative and quantitative assessments, as well as MRI findings, were retrospectively analysed using a double blind method by three radiologists in consensus. Results: Four lesions were located in the cerebellum, among them, one was accompanied by an arachnoid cyst; one huge lesion crossed the parenchyma of the frontal and temporal lobes; the other was located in the left temporal lobe. Two lesions had a homogeneous CSF-like intensity on both T1WI and T2WI. The other four were of mixed-intensity on both T1WI and T2WI. All lesions were strikingly hyperintense on DWI, and iso- or slightly hypointense on ADC (relative to the brain). The mADCs of the ECs were significantly higher than that of GM, but significantly lower than that of CSF. Three cases (3/6) were accurately diagnosed using conventional MR sequences without DWI, but in the remaining three cases, correct diagnosis could only be made with help of DWI. Conclusion: DWI sequences can facilitate the diagnosis of intraparenchymal ECs, thus alerting surgeons of the risk of chemical meningitis at surgery. The MR findings of intraparenchymal ECs are basically as the same as those of extracerebral ECs, but the former is likely to have a mixed signal. The hyperintense signal of ECs on DWI is probably caused by the T2 shine-through effect in tumour tissue.

  19. Relationship between cortex and pulvinar abnormalities on diffusion-weighted imaging in status epilepticus.

    Science.gov (United States)

    Nakae, Yoshiharu; Kudo, Yosuke; Yamamoto, Ryoo; Dobashi, Yuichi; Kawabata, Yuichi; Ikeda, Shingo; Yokoyama, Mutsumi; Higashiyama, Yuichi; Doi, Hiroshi; Johkura, Ken; Tanaka, Fumiaki

    2016-01-01

    The aim of this study was to analyze the pattern of magnetic resonance diffusion-weighted imaging (DWI) findings in status epilepticus in terms of clinical characteristics. Participants comprised 106 patients with status epilepticus who were admitted to our hospital and underwent DWI. Forty-five patients (42.5 %) showed abnormal findings on DWI and were divided into two groups, comprising 26 patients (24.5 %) with cortex lesions alone and 19 patients (17.9 %) with cortex and pulvinar lesions in the same hemisphere. A long duration of status epilepticus (>120 min) tended to be more prevalent among patients with cortex and pulvinar lesions (57.9 %) than among patients with cortex lesions alone (30.8 %) by univariate and multivariate analyses. Todd's palsy tended to be more frequent in patients with abnormalities on DWI (24/45, 53.3 %) than in patients with normal DWI (21/61, 34.4 %). Six of the 26 patients with cortex lesions alone (23.1 %) had taken anti-epileptic drugs before the attack compared to none of the 19 patients with both cortex and pulvinar lesions. The trend toward a longer duration of status epilepticus in patients with both cortex and pulvinar lesions favors a spreading pattern of seizure discharge from cortex to pulvinar via cortico-pulvinar pathways, and anti-epileptic drugs might, to some extent, prevent spreading of seizure discharge from cortex to pulvinar. In addition, existence of high-intensity areas on DWI at the onset of epilepsy may be a predictive factor for the occurrence of Todd's palsy.

  20. Diffusion-weighted breast imaging at 3 T: Preliminary experience

    International Nuclear Information System (INIS)

    Nogueira, L.; Brandão, S.; Matos, E.; Nunes, R.G.; Ferreira, H.A.; Loureiro, J.; Ramos, I.

    2014-01-01

    Aim: To evaluate the performance of diffusion-weighted imaging (DWI) at 3 T for the detection and characterization of breast lesions. Materials and methods: Magnetic resonance imaging (MRI) of the breast, including DWI single-shot spin-echo echo planar images (SS-SE-EPI; eight b-values, 50–3000 s/mm 2 ), were acquired in women with a clinical indication for breast MRI. The exclusion criteria were as follows: (1) previous breast surgery, radiotherapy and/or chemotherapy within the prior 48 months (14 women); (2) only cystic lesions (one woman); (3) no detectable enhancing lesion at dynamic contrast-enhanced (DCE)-MRI (15 women); and (4) breast implants (four women). MRI results were corroborated by histopathology or imaging follow-up. Apparent diffusion coefficients (ADCs) were estimated for lesions and normal glandular tissue. Differences in the ADC between tissue types were evaluated and the sensitivity and specificity of the method calculated by receiver operating characteristics (ROC) curves. Results: The final cohort comprised 53 patients with 59 lesions. Histopathology was obtained for 58 lesions. One lesion was validated as benign on imaging follow-up. Mean ADCs of 1.99 ± 0.27 × 10 −3  mm 2 /s, 1.08 ± 0.25 × 10 −3  mm 2 /s, and 1.74 ± 0.35 × 10 −3  mm 2 /s were obtained for normal tissue, malignant, and benign lesions, respectively. Mean ADCs of malignancies were significantly lower than those of benign lesions (p < 0.001) and normal tissue (p < 0.0001). The sensitivity and specificity for stratifying lesions, considering an ADC threshold of 1.41 × 10 −3  mm 2 /s, were 94.3% and 87.5%, respectively; accuracy was 91.5%. Conclusion: DWI proved useful for the detection and characterization of breast lesions in the present sample. ADC values provide a high diagnostic performance for differentiation between benign and malignant lesions

  1. Imaging of postthalamic visual fiber tracts by anisotropic diffusion weighted MRI and diffusion tensor imaging: principles and applications

    International Nuclear Information System (INIS)

    Reinges, Marcus H.T.; Schoth, Felix; Coenen, Volker A.; Krings, Timo

    2004-01-01

    Diffusion weighted MRI offers the possibility to study the course of the cerebral white matter tracts. In the present manuscript, the basics, the technique and the limitations of diffusion tensor imaging and anisotropic diffusion weighted MRI are presented and their applications in various neurological and neurosurgical diseases are discussed with special emphasis on the visual system. A special focus is laid on the combination of fiber tract imaging, anatomical imaging and functional MRI for presurgical planning and intraoperative neuronavigation of lesions near the visual system

  2. Diffuse axonal injury: detection of changes in anisotropy of water diffusion by diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Chan, J.H.M.; Tsui, E.Y.K.; Yuen, M.K.; Peh, W.C.G.; Fong, D.; Fok, K.F.; Leung, K.M.; Fung, K.K.L.

    2003-01-01

    Myelinated axons of white matter demonstrate prominent directional differences in water diffusion. We performed diffusion-weighted imaging on ten patients with head injury to explore the feasibility of using water diffusion anisotropy for quantitating diffuse axonal injury. We showed significant decrease in diffusion anisotropy indices in areas with or without signal abnormality on T2 and T2*-weighted images. We conclude that the water diffusion anisotropy index a potentially useful, sensitive and quantitative way of diagnosing and assessing patients with diffuse axonal injury. (orig.)

  3. Diffusion-weighted imaging of the rat pelvis using 3D water-excitation MP-RAGE MR sequence

    International Nuclear Information System (INIS)

    Numano, Tomokazu; Homma, Kazuhiro; Hyodo, Koji; Nitta, Naotaka; Iwasaki, Nobuaki

    2008-01-01

    We developed a novel technique for fat-saturated, 3-dimensional (3D) diffusion-weighted (DW) magnetic resonance (MR) imaging sequencing based upon the 3D magnetization-prepared, rapid gradient-echo (3D-MP-RAGE) method. We saturated fat using 2 techniques, chemical shift selective (CHESS; FatSat)-3D-DWI sequence versus water excitation (WE)-3D-DWI method, then compared the 2 sequences in terms of degree of fat suppression. In preparing the FatSat-3D-DWI sequence, we used a ''CHESS-90deg radiofrequency (RF)-motion probing gradient (MPG)-180deg RFMPG-90deg RF'' pulse-train, to sensitize the magnetization to fat-saturated diffusion. In contrast, in the WE-3D-DWI sequence, we selected a RAGE-excitation pulse with a binominal-pulse 1-1 or 1-2-1 for water-excited (fat-saturated) diffusion imaging. Experimental results in a phantom confirmed the effects of diffusion weighting and of fat saturation. Fat saturation was much better in the WE-3D-DWI sequence than the CHESS-3D-DWI sequence. From results from animal (rat pelvis) experiments using WE-3D-DWI, we obtained fat-saturated DWI. This sequence was useful for in vivo imaging. (author)

  4. Diffusion-weighted imaging helps differentiate multiple sclerosis and neuromyelitis optica-related acute optic neuritis.

    Science.gov (United States)

    Wan, Hailin; He, Huijin; Zhang, Fang; Sha, Yan; Tian, Guohong

    2017-06-01

    To evaluate the apparent diffusion coefficient (ADC) values between multiple sclerosis (MS) and neuromyelitis optica (NMO)-related acute optic neuritis (ON) patients and predict their optic nerve atrophy of optic coherence tomography (OCT) parameters. Nineteen MS and 15 NMO-related acute ON patients who underwent a diffusion-weighted imaging sequence in 3.0 Tesla MR scanner and a follow-up OCT examination after 6 months were included. The ADC values, thickness of the retinal nerve fiber layer (RNFL) and the macular ganglion cell complex (GCC) between MS and NMO related ON were assessed. The mean ADC value of the NMO-ON, (0.691 ± 0.195[SD]) × 10 -3 mm 2 /s, was significantly smaller (P = 0.0133) than that of MS-ON. The mean ADC value of MS-ON, (0.879 ± 0.144) × 10 -3 mm 2 /s, was significantly smaller (P < 0.0001) than that of control group, (1.025 ± 0.067) × 10 -3 mm 2 /s. Using an ADC value smaller than 0.830 × 10 -3 mm 2 /s as the threshold value for differentiating MS-ON from NMO-ON patients, the highest accuracy of 76.7%, with 75.0% sensitivity and 78.3% specificity, was obtained. The ADC value measured at the acute stage of ON was correlated with the thickness of the RNFL (r = 0.441; P = 0.006) and the GCC (r = 0.526; P < 0.0001) after 6 months. The ADC value might be helpful for differentiating MS-ON from NMO-ON patients. The decreased ADC value was correlated with optic nerve atrophy on OCT. 3 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;45:1780-1785. © 2016 International Society for Magnetic Resonance in Medicine.

  5. Whole-body MRI, dynamic contrast-enhanced MRI, and diffusion-weighted imaging for the staging of multiple myeloma

    Energy Technology Data Exchange (ETDEWEB)

    Dutoit, Julie C.; Verstraete, Koenraad L. [Ghent University Hospital, Department of Radiology, Ghent (Belgium)

    2017-06-15

    Magnetic resonance imaging (MRI) is the most sensitive imaging technique for the detection of bone marrow infiltration, and has therefore recently been included in the new diagnostic myeloma criteria, as proposed by the International Myeloma Working Group. Nevertheless, conventional MRI only provides anatomical information and is therefore only of limited use in the response assessment of patients with multiple myeloma. The additional information from functional MRI techniques, such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, can improve the detection rate of bone marrow infiltration and the assessment of response. This can further enhance the sensitivity and specificity of MRI in the staging of multiple myeloma patients. This article provides an overview of the technical aspects of conventional and functional MRI techniques with practical recommendations. It reviews the diagnostic performance, prognostic value, and role in therapy assessment in multiple myeloma and its precursor stages. (orig.)

  6. MR diffusion weighted imaging with background signal suppression in breast cancer

    International Nuclear Information System (INIS)

    Li Ming; Zhang Bing; Zhou Zhengyang; Yu Haiping; Yuan Lei; Zhu Bin

    2009-01-01

    Objective: To explore the feasibility of echo planar imaging with short time inversion recovery (STIR-EPI) diffusion weighted imaging with background signal (DWIBS) suppression in breast cancer. Methods: The diffusion weighted imaging (DWI)with background suppression (b=800 mm 2 /s) was performed in 26 patients with breast cancer. Apparent diffusion coefficient(ADC) of all lesions were measured and compared. 3D maximum intensity projection (3D-MIP)and reverse black and white technique were used to show the lesions. DWI and DWIBS were performed and compared for the detection of breast cancer. Randomized blocks analysis of variance was used for the ADC values in different breast tissues, the ADC values in breast cancer and benign lesion were compared using t test. The paired chi square test was used for the detection rate of breast cancer in two different imaging methods. Results: Most of the breast cancers were hyperintense on DWI (b=800 mm 2 /s). The ADC value of cancer tissue was (0.93±0.25) x 10 -3 mm 2 /s, tumor necrosis was (2.06±0.17) x 10 -3 mm 2 /s, normal breast tissue was (1.92±0.23) x 10 -3 mm 2 /s and metastatic lymph node was (1.10±0.14) x 10 -3 mm 2 /s and the differences were statistically significant between two structures (P 2 =8.307, P 2 = 12.235, P -3 mm 2 /s and benign lesion (2.15±0.53) x 10 -3 mm 2 /s had significant statistical differences (t=8.626,P<0.05). Conclusion: Diffusion weighted MRI with background suppression can detect more lesions than DWI and can be potentially applied for the detection of the breast cancer combining the ADC value. (authors)

  7. Diffusion-weighted MR imaging in postoperative follow-up: Reliability for detection of recurrent cholesteatoma

    Energy Technology Data Exchange (ETDEWEB)

    Cimsit, Nuri Cagatay [Marmara University Hospital, Department of Radiology, Istanbul (Turkey); Engin Sitesi Peker Sokak No:1 D:13, 34330 Levent, Istanbul (Turkey)], E-mail: cagataycimsit@gmail.com; Cimsit, Canan [Goztepe Education and Research Hospital, Department of Radiology, Istanbul (Turkey); Istanbul Goztepe Egitim ve Arastirma Hastanesi, Radyoloji Klinigi, Goztepe, Istanbul (Turkey)], E-mail: ccimsit@ttmail.com; Baysal, Begumhan [Goztepe Education and Research Hospital, Department of Radiology, Istanbul (Turkey); Istanbul Goztepe Egitim ve Arastirma Hastanesi, Radyoloji Klinigi, Goztepe, Istanbul (Turkey)], E-mail: begumbaysal@yahoo.com; Ruhi, Ilteris Cagatay [Goztepe Education and Research Hospital, Department of ENT, Istanbul (Turkey); Istanbul Goztepe Egitim ve Arastirma Hastanesi, KBB Klinigi, Goztepe, Istanbul (Turkey)], E-mail: cruhi@yahoo.com; Ozbilgen, Suha [Goztepe Education and Research Hospital, Department of ENT, Istanbul (Turkey); Istanbul Goztepe Egitim ve Arastirma Hastanesi, KBB Klinigi, Goztepe, Istanbul (Turkey)], E-mail: sozbilgen@yahoo.com; Aksoy, Elif Ayanoglu [Acibadem Bakirkoy Hospital, Department of ENT, Istanbul (Turkey); Acibadem Hastanesi, KBB Boeluemue, Bakirkoey, Istanbul (Turkey)], E-mail: elifayanoglu@yahoo.com

    2010-04-15

    Introduction: Cholesteatoma is a progressively growing process that destroy the neighboring bony structures and treatment is surgical removal. Follow-up is important in the postoperative period, since further surgery is necessary if recurrence is present, but not if granulation tissue is detected. This study evaluates if diffusion-weighted MR imaging alone can be a reliable alternative to CT, without use of contrast agent for follow-up of postoperative patients in detecting recurrent cholesteatoma. Materials and methods: 26 consecutive patients with mastoidectomy reporting for routine follow-up CT after mastoidectomy were included in the study, if there was loss of middle ear aeration on CT examination. MR images were evaluated for loss of aeration and signal intensity changes on diffusion-weighted sequences. Surgical results were compared with imaging findings. Results: Interpretation of MR images were parallel with the loss of aeration detected on CT for all 26 patients. Of the 26 patients examined, 14 were not evaluated as recurrent cholesteatoma and verified with surgery (NPV: 100%). Twelve patients were diagnosed as recurrent cholesteatoma and 11 were surgically diagnosed as recurrent cholesteatoma (PPV: 91.7%). Four of these 11 patients had loss of aeration size greater than the high signal intensity area on DWI, which were surgically confirmed as granulation tissue or fibrosis accompanying recurrent cholesteatoma. Conclusion: Diffusion-weighted MR for suspected recurrent cholesteatoma is a valuable tool to cut costs and prevent unnecessary second-look surgeries. It has the potential to become the MR sequence of choice to differentiate recurrent cholesteatoma from other causes of loss of aeration in patients with mastoidectomy.

  8. Diffusion weighted imaging demystified. The technique and potential clinical applications for soft tissue imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ahlawat, Shivani [The Johns Hopkins Medical Institutions, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Fayad, Laura M. [The Johns Hopkins Medical Institutions, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); The Johns Hopkins Medical Institutions, Department of Oncology, Baltimore, MD (United States); The Johns Hopkins Medical Institutions, Department of Orthopaedic Surgery, Baltimore, MD (United States)

    2018-03-15

    Diffusion-weighted imaging (DWI) is a fast, non-contrast technique that is readily available and easy to integrate into an existing imaging protocol. DWI with apparent diffusion coefficient (ADC) mapping offers a quantitative metric for soft tissue evaluation and provides information regarding the cellularity of a region of interest. There are several available methods of performing DWI, and artifacts and pitfalls must be considered when interpreting DWI studies. This review article will review the various techniques of DWI acquisition and utility of qualitative as well as quantitative methods of image interpretation, with emphasis on optimal methods for ADC measurement. The current clinical applications for DWI are primarily related to oncologic evaluation: For the assessment of de novo soft tissue masses, ADC mapping can serve as a useful adjunct technique to routine anatomic sequences for lesion characterization as cyst or solid and, if solid, benign or malignant. For treated soft tissue masses, the role of DWI/ADC mapping in the assessment of treatment response as well as recurrent or residual neoplasm in the setting of operative management is discussed, especially when intravenous contrast medium cannot be given. Emerging DWI applications for non-neoplastic clinical indications are also reviewed. (orig.)

  9. Diffusion weighted imaging demystified. The technique and potential clinical applications for soft tissue imaging

    International Nuclear Information System (INIS)

    Ahlawat, Shivani; Fayad, Laura M.

    2018-01-01

    Diffusion-weighted imaging (DWI) is a fast, non-contrast technique that is readily available and easy to integrate into an existing imaging protocol. DWI with apparent diffusion coefficient (ADC) mapping offers a quantitative metric for soft tissue evaluation and provides information regarding the cellularity of a region of interest. There are several available methods of performing DWI, and artifacts and pitfalls must be considered when interpreting DWI studies. This review article will review the various techniques of DWI acquisition and utility of qualitative as well as quantitative methods of image interpretation, with emphasis on optimal methods for ADC measurement. The current clinical applications for DWI are primarily related to oncologic evaluation: For the assessment of de novo soft tissue masses, ADC mapping can serve as a useful adjunct technique to routine anatomic sequences for lesion characterization as cyst or solid and, if solid, benign or malignant. For treated soft tissue masses, the role of DWI/ADC mapping in the assessment of treatment response as well as recurrent or residual neoplasm in the setting of operative management is discussed, especially when intravenous contrast medium cannot be given. Emerging DWI applications for non-neoplastic clinical indications are also reviewed. (orig.)

  10. MR imaging of hypoglycemic encephalopathy: lesion distribution and prognosis prediction by diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Jeong-Hyun; Kim, Young-Joo; Yoo, Won-Jong; Ihn, Yon-Kwon; Kim, Jee-Young; Kim, Bum-Soo [The Catholic University of Korea, Department of Radiology, College of Medicine, Uijongbu, Kyunggi-do (Korea); Song, Ha-Hun [Cheju Halla General Hospital, Department of Radiology, Jeju (Korea)

    2009-10-15

    The aim of this study was to evaluate the patterns of hypoglycemic encephalopathy on diffusion-weighted imaging (DWI) and the relationship between the imaging patterns and clinical outcomes. This retrospective study included 17 consecutive patients that had hypoglycemic encephalopathy with DWI abnormalities. The topographic distributions of the DWI abnormalities of the cortex, deep gray matter, and white matter structures were assessed. In addition, possible correlation between the patterns of brain injury on DWI and clinical outcomes was investigated. There were three patterns of DWI abnormalities: involvement of both gray and white matter (n=8), selective involvement of gray matter (n=4), and selective involvement of white matter (n=5). There was no significant difference in the initial blood glucose levels among patients for each of the imaging patterns. Most patients (16/17) had bilateral symmetrical abnormalities. Among patients with bilateral symmetrical gray and/or white matter injuries, one had moderate to severe disability and 14 remained in a persistent vegetative state. The two patients with a focal unilateral white matter abnormality and a localized splenial abnormality recovered without neurological deficits. The results of this study showed that white matter was more sensitive to hypoglycemia than previously thought and there was no specific association between the patterns of injury and clinical outcomes whether the cerebral cortex, deep gray matter, and/or white matter were affected. Diffuse and extensive injury observed on the DWI predicts a poor neurologic outcome in patients with hypoglycemic injuries. (orig.)

  11. Evaluation of gastric cancer detectability on respiratory triggered-diffusion weighted image

    International Nuclear Information System (INIS)

    Ichiba, Noriatsu; Fukuda, Kunihiko; Takahashi, Naoto; Nikaido, Takashi; Urashima, Mitsuyoshi; Kitagawa, Hisashi

    2007-01-01

    The objective of this study was to assess the ability of respiratory triggered diffusion-weighted image (RT-DWI) to detect gastric cancer and to determine whether there is any correlation between the detectability of RT-DWI and the location of cancerous tissues. Sixty-nine gastric cancer patients (71 lesions) underwent pre-operative magnetic resonance (MR) imaging and total or partial gastrectomy. Scans of the stomach were acquired using a 1.5T MR scanner. Our protocol consisted of T1WI, T2WI and DWI (b value=800 sec/mm 2 ). The location of gastric cancer was classified into three areas -U, M and L. The condition of the gastric contents and the relation between the location of intraluminal gas and gastric lesions were also evaluated. There were 42 early gastric cancers and 29 advanced cancers in a total of 71 lesions. In early gastric cancers, 15 lesions were detected out of 42 lesions (35.7%) and, in advanced gastric cancers, 27 lesions were detected out of 29 lesions (93.0%). Pathological volumes of the detected lesions ranged between 12 mm x 8 mm x 1 mm and 190 mm x 135 mm x 10 mm (median 57 mm x 35 mm x 5 mm), and those of the undetected lesions ranged between 5 mm x 2 mm x 1 mm and 67 mm x 47 mm x 1.5 mm (median 23 mm x 17 mm x 1 mm). Detectability of the lesions appeared to be higher in the following three conditions when the gastric lumen was filled with mainly fluid rather than gas when there was no intraluminal gas adjacent to the lesion when the imaging quality of RT-DWI was good. RT-DWI was found to have a high detection (93.0%) rate of advanced gastric cancers. To improve the detectability of early gastric cancers, we should endeavor to minimize the susceptibility artifact from intraluminal gas in the stomach and select higher resolution protocols. (author)

  12. Diffusion-weighted MR imaging in the early diagnosis of periventricular leukomalacia

    International Nuclear Information System (INIS)

    Bozzao, Alessandro; Di Paolo, Ambrogio; Simonetti, Alessandra; Mazzoleni, Clarissa; Fasoli, Fabrizio; Floris, Roberto; Fantozzi, Luigi Maria

    2003-01-01

    Diffusion-weighted imaging (DWI) has been shown to be highly sensitive in detecting acute cerebral infarction, but its use in detecting hypoxic-ischemic encephalopathy (HIE) in neonates is still controversial. Moreover, few reports concern pre-term infants with possible periventricular leukomalacia (PVL). We examined the ability of this technique to detect cerebral changes in the acute phase of PVL. Fifteen MR examinations were performed in 11 pre-term infants (mean age 3.4 days, range 2-6 days). Conventional DWI sequences, apparent diffusion coefficient (ADC) maps, and US obtained in the acute phase were compared. All the neonates underwent US follow-up up to 4 months after delivery; those with suspected PVL also underwent MRI follow-up for up to 2 months. Qualitative and quantitative evaluations were performed to assess the presence of DW changes compatible with PVL. Diffusion-weighted MRI showed signal hyperintensity associated with decreased ADC values in 3 subjects (27%). In these patients conventional MRI sequences were interpreted as normal and US (performed at the same time) as doubtful in 2 and compatible with PVL in 1 subject. The MRI and US follow-up confirmed severe damage in all these patients. In 1 neonate hemorrhages involving the germinative matrix were identified. In 8 neonates MRI was considered normal. In these subjects US follow-up (up to 4 months) confirmed no signs of PVL. Diffusion-weighted imaging may have a higher correlation with later evidence of PVL than does conventional MR imaging and US when performed in the acute phase of the disease. (orig.)

  13. Diffusion-Weighted MR Imaging of Unusual White Matter Lesion in a Patient with Menkes Disease

    International Nuclear Information System (INIS)

    Lee, Eun Shin; Ryoo, Jae Wook; Choi, Dae Seob; Cho, Jae Min; Kwon, Soo Hyun; Shin, Hee Suk

    2007-01-01

    We report here on the diffusion-weighted imaging of unusual white matter lesions in a case of Menkes disease. On the initial MR imaging, the white matter lesions were localized in the deep periventricular white matter in the absence of diffuse cortical atrophy. The lesion showed diffuse high signal on the diffusion weighted images and diffuse progression and persistent hyperintensity on the follow up imaging. Our case suggests that the white matter lesion may precede diffuse cortical atrophy in a patient with Menkes disease. Menkes disease is an X-linked disorder that's caused by impaired intracellular transport of copper. We describe here the DWI findings of unusual and progressive white matter lesions in a case of Menkes disease. Menkes disease is an X-linked recessive disorder, and it is due to an inborn error of copper metabolism. The cause of Menkes disease has been isolated to a genetic defect in copper-transporting adenosine triphosphatase, and this results in low levels of intracellular copper. It is characterized clinically by failure to thrive, retarded mental and motor development, clonic seizure and peculiarly coarse, sparse and colorless scalp hair. These clinical findings can be explained by a dysfunction of the copper-dependent enzymes

  14. Contribution of diffusion-weighted MR imaging for predicting benignity of complex adnexal masses

    International Nuclear Information System (INIS)

    Thomassin-Naggara, Isabelle; Darai, Emile; Cuenod, Charles A.; Fournier, Laure; Toussaint, Irwin; Marsault, Claude; Bazot, Marc

    2009-01-01

    The purpose of this study was to prospectively assess the contribution of diffusion-weighted MR imaging (DWI) for characterizing complex adnexal masses. Seventy-seven women (22-87 years old) with complex adnexal masses (30 benign and 47 malignant) underwent MR imaging including DWI before surgery. Conventional morphological MR imaging criteria were recorded in addition to b 1,000 signal intensity and apparent diffusion coefficient (ADC) measurements of cystic and solid components. Positive likelihood ratios (PLR) were calculated for predicting benignity and malignancy. The most significant criteria for predicting benignity were low b 1,000 signal intensity within the solid component (PLR = 10.9), low T2 signal intensity within the solid component (PLR = 5.7), absence of solid portion (PLR = 3.1), absence of ascites or peritoneal implants (PLR = 2.3) and absence of papillary projections (PLR = 2.3). ADC measurements did not contribute to differentiating benign from malignant adnexal masses. All masses that displayed simultaneously low signal intensity within the solid component on T2-weighted and on b 1,000 diffusion-weighted images were benign. Alternatively, the presence of a solid component with intermediate T2 signal and high b 1,000 signal intensity was associated with a PLR of 4.5 for a malignant adnexal tumour. DWI signal intensity is an accurate tool for predicting benignity of complex adnexal masses. (orig.)

  15. Contribution of diffusion-weighted MR imaging for predicting benignity of complex adnexal masses

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin-Naggara, Isabelle [Hopital Tenon, Assistance Publique Hopitaux de Pariss, Department of Radiology, Paris (France); Universite Rene Descartes, LRI-EA4062, Paris (France); Darai, Emile [Hopital Tenon, Assistance Publique Hopitaux de Pariss, Department of Gynecology-Obstetrics, Paris (France); Cuenod, Charles A.; Fournier, Laure [Universite Rene Descartes, LRI-EA4062, Paris (France); Hopital Europeen Georges Pompidou (HEGP), Assistance Publique Hopitaux de Paris, Department of Radiology, Paris (France); Toussaint, Irwin; Marsault, Claude; Bazot, Marc [Hopital Tenon, Assistance Publique Hopitaux de Pariss, Department of Radiology, Paris (France)

    2009-06-15

    The purpose of this study was to prospectively assess the contribution of diffusion-weighted MR imaging (DWI) for characterizing complex adnexal masses. Seventy-seven women (22-87 years old) with complex adnexal masses (30 benign and 47 malignant) underwent MR imaging including DWI before surgery. Conventional morphological MR imaging criteria were recorded in addition to b{sub 1,000} signal intensity and apparent diffusion coefficient (ADC) measurements of cystic and solid components. Positive likelihood ratios (PLR) were calculated for predicting benignity and malignancy. The most significant criteria for predicting benignity were low b{sub 1,000} signal intensity within the solid component (PLR = 10.9), low T2 signal intensity within the solid component (PLR = 5.7), absence of solid portion (PLR = 3.1), absence of ascites or peritoneal implants (PLR = 2.3) and absence of papillary projections (PLR = 2.3). ADC measurements did not contribute to differentiating benign from malignant adnexal masses. All masses that displayed simultaneously low signal intensity within the solid component on T2-weighted and on b{sub 1,000} diffusion-weighted images were benign. Alternatively, the presence of a solid component with intermediate T2 signal and high b{sub 1,000} signal intensity was associated with a PLR of 4.5 for a malignant adnexal tumour. DWI signal intensity is an accurate tool for predicting benignity of complex adnexal masses. (orig.)

  16. Normal diffusion-weighted imaging in cerebral air embolism complicating angiography

    Energy Technology Data Exchange (ETDEWEB)

    Sayama, T.; Inamura, T.; Fukui, M. [Dept. of Neurosurgery, Kyushu University Hospital, Fukuoka (Japan); Mitani, M.; Yagi, H. [Dept. of Neurosurgery, Yagi Hospital, Fukuoka (Japan)

    2000-03-01

    We report a case of cerebral air embolism resulting from accidental air infection during cerebral angiography. A 60-year-old man was accidentally injected with air via the left subclavian artery. Angiography demonstrated air within the basilar artery. The patient showed signs of posterior circulation ischaemia (confusion, blindness, gaze palsy and hemiparesis). However, MRI, including diffusion-weighted imaging, showed no abnormality 4 h later. The patient was treated with hyperbaric oxygen within 5 h of the embolism. All symptoms and signs resolved completely within a week. (orig.)

  17. The evaluation of diffusion weighted imaging in acute cerebral infarction with permanent type MR scanner

    International Nuclear Information System (INIS)

    Peng Sen; Ye Wenwei; Luo Zhongrao; Yang Zenian; Zhang Zhongwei; Li Ziping

    2006-01-01

    Objective: To evaluate the value of diffusion weighted imaging (DWI) in acute cerebral infarction using permanent type MR scanner. Methods: DWI and conventional MRI sequences were done in 77 patients suspected with cerebral infarction. The sensitivity of DWI and conventional MRI was comparatively evaluated on lesion signal intensity and size. The characteristics and orderliness of lesions were studied. Results: (1) DWI has higher sensitivity than conventional MRI. (2) The higher b value was applied in the imaging, the higher signal intensity of acute cerebral infarction was revealed. The lesions were easier to identify on DWI images than on conventional MRI. Conclusion: DWI of permanent type MR imager is a feasible imaging modality, which is valuable in early diagnosis and management of acute cerebral infarction. (authors)

  18. lop-DWI: A Novel Scheme for Pre-Processing of Diffusion-Weighted Images in the Gradient Direction Domain.

    Science.gov (United States)

    Sepehrband, Farshid; Choupan, Jeiran; Caruyer, Emmanuel; Kurniawan, Nyoman D; Gal, Yaniv; Tieng, Quang M; McMahon, Katie L; Vegh, Viktor; Reutens, David C; Yang, Zhengyi

    2014-01-01

    We describe and evaluate a pre-processing method based on a periodic spiral sampling of diffusion-gradient directions for high angular resolution diffusion magnetic resonance imaging. Our pre-processing method incorporates prior knowledge about the acquired diffusion-weighted signal, facilitating noise reduction. Periodic spiral sampling of gradient direction encodings results in an acquired signal in each voxel that is pseudo-periodic with characteristics that allow separation of low-frequency signal from high frequency noise. Consequently, it enhances local reconstruction of the orientation distribution function used to define fiber tracks in the brain. Denoising with periodic spiral sampling was tested using synthetic data and in vivo human brain images. The level of improvement in signal-to-noise ratio and in the accuracy of local reconstruction of fiber tracks was significantly improved using our method.

  19. New asymptomatic ischemic lesions on diffusion-weighted imaging after cerebral angiography

    International Nuclear Information System (INIS)

    Shibazaki, Kensaku

    2006-01-01

    Conventional cerebral angiography (CAG) is relatively low risk for neurological complications. However, diffusion-weighted imaging (DWI) after CAG occasionally reveal an asymptomatic ischemic lesion on the brain. The aim of this study was to investigate the frequency of new asymptomatic or symptomatic DWI lesions after CAG and to clarify the factors associated with them. Fifty-six patients with acute ischemic stroke and transient ischemic attack were prospectively enrolled. Magnetic resonance imaging (MRI) studies including DWI were studied twice, within 48 hours before and after CAG. The following factors were assessed; age, gender, history of stroke, history of ischemic heart disease, vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score on admission, stroke subtype, treatment before stroke or transient ischemic attack (TIA) (antiplatelets or warfarin), approach for catheters (transbrachial or femoral artery), amount of contrast medium used, length of the angiographic procedure, and fluoroscophy time. We divided the patients into two groups according to the presence of new DWI lesions after CAG; Positive group had new DWI lesions, whereas the Negative group had none. After CAG, no patients had new neurological deficits. New asymptomatic DWI lesions were observed in 24 patients (42.9%). The significant differences observed between two groups were as follows; age (69.8±11.3 for the Positive group versus 61.9±11.3 for the Negative group, p=0.043), female (54% versus 28%, p=0.048), non-small vessel occlusion (100% versus 66%, p=0.009), catheter approach for transfemoral artery (63% versus 13%, p<0.001), mean length of the angiographic procedure (63.1±21.6 min versus 43.7±14.2 min, p<0.001), mean fluoroscopy time (26.5±13.0 min versus 14.9±5.9 mm, p<0.001). Sensitivity and specificity analysis to discriminate the positive and negative groups revealed 17 minutes to be the critical threshold point (sensitivity 66.6% and specificity 68

  20. Diffusion weighted imaging and estimation of prognosis using apparent diffusion coefficient measurements in ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Gonen, Korcan Aysun, E-mail: aysunbalc@yahoo.com [Department of Radiology, State Hospital, Eski Cami district, Hastane street, N:1, 59300, Tekirdag (Turkey); Simsek, Mehmet Masum, E-mail: radyoloji@haydapasanumune.gov.tr [Department of Radiology, Haydarpasa Numune Training and Research Hospital, Tibbiye street, Uskudar 34200, Istanbul (Turkey)

    2010-11-15

    Objective: Estimation of the prognosis of infarction by using diffusion weighted imaging (DWI) and quantitative apparent diffusion coefficient (ADC) measurements. Methods: 23 patients having acute stroke symptoms with verified infarction in magnetic resonance imaging (MRI) were included in this study. Their MRI studies were performed between 6 and 12 h after the onset of their symptoms and were repeated on the fifth day. The infarction volumes were calculated by using DWI and the patients were divided into two groups as the ones having an expansion in the infarction area (group 1, n = 16) and the others having no expansion in the infarction area (group 2, n = 7). Quantitative ADC values were estimated. The groups were compared in terms of the ADC values on ADC maps obtained from DWI, performed during the between 6 and 12 h from the onset of the symptoms, referring to the core of the infarction (ADC{sub IC}), ischemic penumbra (ADC{sub P}) and the nonischemic parenchymal tissue (ADC{sub N}). P values < 0.05 were accepted to be statistically significant. Results: During the between 6 and 12 h mean infarction volume calculated by DWI was 23.3 cm{sup 3} for group 1 patients (ranging from 1.1 to 68.6) and this was found to be 40.3 cm{sup 3} (ranging from 1.8 to 91.5) on the fifth day. For the group 2 patients these values were found to be 42.1 cm{sup 3} (ranging from 1 to 94.7) and 41.9 (ranging from 1 to 94.7) for the same intervals respectively. A significant statistical result was failed to be demonstrated between the mean ADC{sub IC} and ADC{sub N} values (p = 0.350 and p = 0.229 respectively). However the comparison of the ADC{sub P} values between the groups was found to be highly significant (p < 0.001). When the differences between the ADC{sub P} and ADC{sub IC} and ADC{sub N} and ADC{sub P} were compared the results proved to be statistically significant (p = 0.038 and p < 0.001 respectively). Conclusions: We believe that ADC results that would be obtained from

  1. Diffusion weighted imaging and estimation of prognosis using apparent diffusion coefficient measurements in ischemic stroke

    International Nuclear Information System (INIS)

    Gonen, Korcan Aysun; Simsek, Mehmet Masum

    2010-01-01

    Objective: Estimation of the prognosis of infarction by using diffusion weighted imaging (DWI) and quantitative apparent diffusion coefficient (ADC) measurements. Methods: 23 patients having acute stroke symptoms with verified infarction in magnetic resonance imaging (MRI) were included in this study. Their MRI studies were performed between 6 and 12 h after the onset of their symptoms and were repeated on the fifth day. The infarction volumes were calculated by using DWI and the patients were divided into two groups as the ones having an expansion in the infarction area (group 1, n = 16) and the others having no expansion in the infarction area (group 2, n = 7). Quantitative ADC values were estimated. The groups were compared in terms of the ADC values on ADC maps obtained from DWI, performed during the between 6 and 12 h from the onset of the symptoms, referring to the core of the infarction (ADC IC ), ischemic penumbra (ADC P ) and the nonischemic parenchymal tissue (ADC N ). P values 3 for group 1 patients (ranging from 1.1 to 68.6) and this was found to be 40.3 cm 3 (ranging from 1.8 to 91.5) on the fifth day. For the group 2 patients these values were found to be 42.1 cm 3 (ranging from 1 to 94.7) and 41.9 (ranging from 1 to 94.7) for the same intervals respectively. A significant statistical result was failed to be demonstrated between the mean ADC IC and ADC N values (p = 0.350 and p = 0.229 respectively). However the comparison of the ADC P values between the groups was found to be highly significant (p P and ADC IC and ADC N and ADC P were compared the results proved to be statistically significant (p = 0.038 and p < 0.001 respectively). Conclusions: We believe that ADC results that would be obtained from the core and the penumbra of the infarction area will be beneficial in the estimation of the infarction prognosis and in the planning of a treatment protocol.

  2. Diffusion-weighted imaging and proton MR spectroscopy in the characterization of acute disseminated encephalomyelitis

    International Nuclear Information System (INIS)

    Balasubramanya, K.S.; Kovoor, J.M.E.; Jayakumar, P.N.; Ravishankar, S.; Kamble, R.B.; Panicker, J.; Nagaraja, D.

    2007-01-01

    Acute disseminated encephalomyelitis (ADEM) is usually a monophasic illness characterized by multiple lesions involving gray and white matter. Quantitative MR techniques were used to characterize and stage these lesions. Eight patients (seven males and one female; mean age 19 years, range 5 to 36 years) were studied using conventional MRI (T2- and T1-weighted and FLAIR sequences), diffusion-weighted imaging (DWI) and proton magnetic resonance spectroscopy (MRS). Apparent diffusion coefficient (ADC) values and MRS ratios were calculated for the lesion and for normal-appearing white matter (NAWM). Three patients were imaged in the acute stage (within 7 days of the onset of neurological symptoms) and five in the subacute stage (after 7 days from the onset of symptoms). ADC values in NAWM were in the range 0.7-1.24 x 10 -3 mm/s 2 (mean 0.937 ± 0.17 mm/s 2 ). ADC values of ADEM lesions in the acute stage were in the range 0.37-0.68 x 10 -3 mm/s 2 (mean 0.56 ± 0.16 mm/s 2 ) and 1.01-1.31 x 10 -3 mm/s 2 (mean 1.24 ± 0.13 mm/s 2 ) in the subacute stage. MRS ratios were obtained for all patients. NAA/Cho ratios were in the range 1.1-3.5 (mean 1.93 ± 0.86) in the NAWM. NAA/Cho ratios within ADEM lesions in the acute stage were in the range 0.63-1.48 (mean 1.18 ± 0.48) and 0.29-0.84 (mean 0.49 ± 0.22) in the subacute stage. The ADC values, NAA/Cho and Cho/Cr ratios were significantly different between lesions in the acute and subacute stages (P < 0.001, P < 0.027, P < 0.047, respectively). ADC values were significantly different between lesions in the acute (P < 0.009) and subacute stages (P < 0.005) with NAWM. In addition, NAA/Cho and Cho/Cr ratios were significantly different between lesions in the subacute stage and NAWM (P < 0.006, P < 0.007, respectively). ADEM lesions were characterized in the acute stage by restricted diffusion and in the subacute stage by free diffusion and a decrease in NAA/Cho ratios. Restricted diffusion and progressive decrease in NAA

  3. Diffusion-weighted imaging and proton MR spectroscopy in the characterization of acute disseminated encephalomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanya, K.S.; Kovoor, J.M.E.; Jayakumar, P.N.; Ravishankar, S.; Kamble, R.B. [National Institute of Mental Health and Neurosciences, Department of Neuroimaging and Interventional Radiology, Bangalore, Karnataka (India); Panicker, J.; Nagaraja, D. [National Institute of Mental Health and Neurosciences, Department of Neurology, Bangalore (India)

    2007-02-15

    Acute disseminated encephalomyelitis (ADEM) is usually a monophasic illness characterized by multiple lesions involving gray and white matter. Quantitative MR techniques were used to characterize and stage these lesions. Eight patients (seven males and one female; mean age 19 years, range 5 to 36 years) were studied using conventional MRI (T2- and T1-weighted and FLAIR sequences), diffusion-weighted imaging (DWI) and proton magnetic resonance spectroscopy (MRS). Apparent diffusion coefficient (ADC) values and MRS ratios were calculated for the lesion and for normal-appearing white matter (NAWM). Three patients were imaged in the acute stage (within 7 days of the onset of neurological symptoms) and five in the subacute stage (after 7 days from the onset of symptoms). ADC values in NAWM were in the range 0.7-1.24 x 10{sup -3} mm/s{sup 2} (mean 0.937 {+-} 0.17 mm/s{sup 2}). ADC values of ADEM lesions in the acute stage were in the range 0.37-0.68 x 10{sup -3} mm/s{sup 2} (mean 0.56 {+-} 0.16 mm/s{sup 2}) and 1.01-1.31 x 10{sup -3} mm/s{sup 2} (mean 1.24 {+-} 0.13 mm/s{sup 2}) in the subacute stage. MRS ratios were obtained for all patients. NAA/Cho ratios were in the range 1.1-3.5 (mean 1.93 {+-} 0.86) in the NAWM. NAA/Cho ratios within ADEM lesions in the acute stage were in the range 0.63-1.48 (mean 1.18 {+-} 0.48) and 0.29-0.84 (mean 0.49 {+-} 0.22) in the subacute stage. The ADC values, NAA/Cho and Cho/Cr ratios were significantly different between lesions in the acute and subacute stages (P < 0.001, P < 0.027, P < 0.047, respectively). ADC values were significantly different between lesions in the acute (P < 0.009) and subacute stages (P < 0.005) with NAWM. In addition, NAA/Cho and Cho/Cr ratios were significantly different between lesions in the subacute stage and NAWM (P < 0.006, P < 0.007, respectively). ADEM lesions were characterized in the acute stage by restricted diffusion and in the subacute stage by free diffusion and a decrease in NAA/Cho ratios

  4. Diagnosis and quantification of hepatic fibrosis in children with diffusion weighted MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Razek, Ahmed Abdel Khalek Abdel, E-mail: arazek@mans.eun.eg [Diagnostic Radiology Department, Mansoura Faculty of Medicine, 62 ElNokrasi Street Meet Hadr, Mansoura 3512 (Egypt); Abdalla, Ahmed [Pediatric Department, Mansoura Faculty of Medicine, Mansoura (Egypt); Omran, Eman [Diagnostic Radiology Department, Mansoura Faculty of Medicine, 62 ElNokrasi Street Meet Hadr, Mansoura 3512 (Egypt); Fathy, Abeer [Pediatric Department, Mansoura Faculty of Medicine, Mansoura (Egypt); Zalata, Khaled [Diagnostic Pathology Department, Mansoura Faculty of Medicine, Mansoura (Egypt)

    2011-04-15

    Purpose: To evaluate the accuracy of diffusion weighted MR imaging in diagnosis and quantification of hepatic fibrosis in children with chronic hepatitis. Materials and methods: Sixty-three consecutive children (40 boys, 23 girls, median age 9.3 years), with chronic hepatitis and thirty age matched volunteers underwent diffusion weighted MR imaging of the liver using a single shot echoplanar imaging with b-value = 0, 250, and 500 s/mm{sup 2}. Liver biopsy was obtained with calculation of METAVIR score. The ADC value of the liver was correlated with METAVIR score. Receiver operating characteristic curve was done for diagnosis and grading of hepatic fibrosis. Results: There was statistical difference in the mean ADC value between volunteers and patients with hepatic fibrosis (P = 0.001) and in patients with different grades of METAVIR scores (P = 0.002). There was correlation between the mean ADC value and METAVIR score (r = 0.807, P = 0.001). The cut off point to predict fibrosis (1.7 x 10{sup -3} mm{sup 2}/s) revealed 83% accuracy, 85% sensitivity, 82% specificity, 83% PPV, and 85% NPV. The area under the curve was 0.91 for F1, 0.85 for F2, 0.86 for F3 and 0.90 for F4. Conclusion: The apparent diffusion coefficient value is a promising quantitative parameter used for diagnosis and quantification of hepatic fibrosis in children with chronic hepatitis.

  5. Diffusion-weighted imaging: basic concepts and application in cerebral stroke and head trauma

    International Nuclear Information System (INIS)

    Huisman, Thierry A.G.M.

    2003-01-01

    Diffusion-weighted imaging (DWI) of the brain represents a new imaging technique that extends imaging from depiction of neuroanatomy to the level of function and physiology. DWI measures a fundamentally different physiological parameter compared with conventional MRI. Image contrast is related to differences in the diffusion rate of water molecules rather than to changes in total tissue water. DWI can reveal pathology in cases where conventional MRI remains unremarkable. DWI has proven to be highly sensitive in the early detection of acute cerebral ischemia and seems promising in the evaluation of traumatic brain injury. DWI can differentiate between lesions with decreased and increased diffusion. In addition, full-tensor DWI can evaluate the microscopic architecture of the brain, in particular white matter tracts, by measuring the degree and spatial distribution of anisotropic diffusion within the brain. This article reviews the basic concepts of DWI and its application in cerebral ischemia and traumatic brain injury. (orig.)

  6. Diffusion-weighted imaging: basic concepts and application in cerebral stroke and head trauma

    Energy Technology Data Exchange (ETDEWEB)

    Huisman, Thierry A.G.M. [Department of Radiology, Neuroradiology Section and MGH-NMR Center, Massachusetts General Hospital and Harvard Medical School, MA 02129, Boston (United States); Department of Radiology, University Children' s Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich (Switzerland)

    2003-10-01

    Diffusion-weighted imaging (DWI) of the brain represents a new imaging technique that extends imaging from depiction of neuroanatomy to the level of function and physiology. DWI measures a fundamentally different physiological parameter compared with conventional MRI. Image contrast is related to differences in the diffusion rate of water molecules rather than to changes in total tissue water. DWI can reveal pathology in cases where conventional MRI remains unremarkable. DWI has proven to be highly sensitive in the early detection of acute cerebral ischemia and seems promising in the evaluation of traumatic brain injury. DWI can differentiate between lesions with decreased and increased diffusion. In addition, full-tensor DWI can evaluate the microscopic architecture of the brain, in particular white matter tracts, by measuring the degree and spatial distribution of anisotropic diffusion within the brain. This article reviews the basic concepts of DWI and its application in cerebral ischemia and traumatic brain injury. (orig.)

  7. Segmentation of Hyperacute Cerebral Infarcts Based on Sparse Representation of Diffusion Weighted Imaging

    Directory of Open Access Journals (Sweden)

    Xiaodong Zhang

    2016-01-01

    Full Text Available Segmentation of infarcts at hyperacute stage is challenging as they exhibit substantial variability which may even be hard for experts to delineate manually. In this paper, a sparse representation based classification method is explored. For each patient, four volumetric data items including three volumes of diffusion weighted imaging and a computed asymmetry map are employed to extract patch features which are then fed to dictionary learning and classification based on sparse representation. Elastic net is adopted to replace the traditional L0-norm/L1-norm constraints on sparse representation to stabilize sparse code. To decrease computation cost and to reduce false positives, regions-of-interest are determined to confine candidate infarct voxels. The proposed method has been validated on 98 consecutive patients recruited within 6 hours from onset. It is shown that the proposed method could handle well infarcts with intensity variability and ill-defined edges to yield significantly higher Dice coefficient (0.755 ± 0.118 than the other two methods and their enhanced versions by confining their segmentations within the regions-of-interest (average Dice coefficient less than 0.610. The proposed method could provide a potential tool to quantify infarcts from diffusion weighted imaging at hyperacute stage with accuracy and speed to assist the decision making especially for thrombolytic therapy.

  8. [Examination of upper abdominal region in high spatial resolution diffusion-weighted imaging using 3-Tesla MRI].

    Science.gov (United States)

    Terada, Masaki; Matsushita, Hiroki; Oosugi, Masanori; Inoue, Kazuyasu; Yaegashi, Taku; Anma, Takeshi

    2009-03-20

    The advantage of the higher signal-to-noise ratio (SNR) of 3-Tesla magnetic resonance imaging (3-Tesla) has the possibility of contributing to the improvement of high spatial resolution without causing image deterioration. In this study, we compared SNR and the apparent diffusion coefficient (ADC) value with 3-Tesla as the condition in the diffusion-weighted image (DWI) parameter of the 1.5-Tesla magnetic resonance imaging (1.5-Tesla) and we examined the high spatial resolution images in the imaging method [respiratory-triggering (RT) method and breath free (BF) method] and artifact (motion and zebra) in the upper abdominal region of DWI at 3-Tesla. We have optimized scan parameters based on phantom and in vivo study. As a result, 3-Tesla was able to obtain about 1.5 times SNR in comparison with the 1.5-Tesla, ADC value had few differences. Moreover, the RT method was effective in correcting the influence of respiratory movement in comparison with the BF method, and image improvement by the effective acquisition of SNR and reduction of the artifact were provided. Thus, DWI of upper abdominal region was a useful sequence for the high spatial resolution in 3-Tesla.

  9. Diffusion-weighted imaging in the evaluation of hormonal cyclic changes in abdominal wall endometriomas

    International Nuclear Information System (INIS)

    Genç, B.; Solak, A.; Şahin, N.; Genç, M.; Oğul, H.; Sivrikoz, O. Nermin; Kantarcı, M.

    2014-01-01

    Aim: To investigate the utility of diffusion-weighted (DW) magnetic resonance imaging (MRI) in the diagnosis of abdominal wall endometrioma (AWE) and to compare the ADC (apparent diffusion coefficient) values of AWE with those of the uterine endometrium during two different phases of the menstrual cycle. Materials and methods: A total of 22 women aged between 27 and 42 years (mean 32.8 years) and who had regular menstrual cycles were included in the study. These patients had a total of 25 AWE lesions. The mean and standard deviation of the ADC values of the normal endometrium/AWE were calculated for the menstrual and luteal phases. All examinations were performed using a 1.5 T magnet (b-values of 50, 400, and 800 mm/s 2 ). The results were analysed using the Shapiro–Wilk test, the Pearson correlation test, the analysis of variance (ANOVA) test, and the paired sample t-test. Results: The ADC values of the endometrium were different in the two phases of the menstrual cycle (menstrual phase: 0.924 ± 0.171; luteal phase: 1.171 ± 0.135). Similarly, the ADC values of the AWE were different in these phases (menstrual phase: 0.937 ± 0.256, luteal phase: 1.256 ± 0.215). In both AWE and the uterine endometrium, the ADC measurements were significantly lower in the menstrual phase than during the luteal phase. This difference was statistically significant (p < 0.05). There was no significant difference in the ADC values between the endometrial layer and AWE during the same phase (p = 0.216 for menstrual phase, p = 0.104 for luteal phase, paired sample t-test). Conclusion: The present study demonstrated that in all patients, the DWI features of AWEs were significantly similar to those of the uterine endometrial tissue. Additionally, the ADC measurements of the patients showed similar cyclical changes. These results suggest that the ADC values of a lesion close to the uterine endometrium may be used to differentiate AWE from the other disease entities of the abdominal wall

  10. Diffusion weighted MR imaging in non-infarct lesions of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Karaarslan, E. [Department of Radiology, American Hospital, Sisli, Istanbul (Turkey)], E-mail: ercankaraarslan@yahoo.com; Arslan, A. [Department of Radiology, Kocaeli University Medical School, Kocaeli (Turkey)], E-mail: arzuarslan@netscape.net

    2008-03-15

    Diffusion weighted imaging (DWI) is a relatively new method in which the images are formed by the contrast produced by the random microscopic motion of water molecules in different tissues. Although DWI has been tried for different organ systems, it has been found its primary use in the central nervous system. The most widely used clinical application is in the detection of hyperacute infarcts and the differentiation of acute or subacute infarction from chronic infarction. Recently DWI has been applied to various other cerebral diseases. In this pictorial paper the authors demonstrated different DWI patterns of non-infarct lesions of the brain which are hyperintense in the diffusion trace image, such as infectious, neoplastic and demyelinating diseases, encephalopathies - including hypoxic-ischemic, hypertensive, eclamptic, toxic, metabolic and mitochondrial encephalopathies - leukodystrophies, vasculitis and vasculopathies, hemorrhage and trauma.

  11. Myometrial invasion in endometrial cancer: diagnostic performance of diffusion-weighted MR imaging at 1.5-T

    International Nuclear Information System (INIS)

    Rechichi, Gilda; Sironi, Sandro; Galimberti, Stefania; Valsecchi, Maria Grazia; Signorelli, Mauro; Perego, Patrizia

    2010-01-01

    To determine the diagnostic accuracy of diffusion-weighted (DW) magnetic resonance (MR) imaging in the preoperative assessment of myometrial invasion by endometrial cancer. In this prospective study, 47 patients with histologically confirmed endometrial cancer underwent preoperative MR imaging and total hysterectomy. The MR protocol included spin-echo multishot T2-weighted, dynamic T1-weighted and DW images acquired with b-values of 0 and 500 s/mm 2 . Myometrial tumour spread was classified as superficial (<50%) or deep (≥50% myometrial thickness). Postoperative histopathological findings served as a reference standard. Indices of diagnostic performance were assessed for each sequence. At histopathological examination, superficial myometrial invasion was found in 34 patients and deep myometrial invasion in 13. In the assessment of tumour invasion, sensitivity, specificity, positive and negative predictive values of T2-weighted images were 92.3%, 76.5%, 60.0% and 96.3%, respectively. The corresponding values for dynamic images were 69.2%, 61.8%, 40.9% and 84.0%, and for DW images 84.6%, 70.6%, 52.4% and 92.3%. T2-weighted and DW imaging proved to be the most accurate techniques for tumour spread determination. DW imaging proved to be accurate in assessing myometrial invasion, and it could replace dynamic imaging as an adjunct to routine T2-weighted imaging for preoperative evaluation of endometrial cancer. (orig.)

  12. DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) Mismatch in Thrombectomy Candidates: An Intrarater and Interrater Agreement Study.

    Science.gov (United States)

    Fahed, Robert; Lecler, Augustin; Sabben, Candice; Khoury, Naim; Ducroux, Célina; Chalumeau, Vanessa; Botta, Daniele; Kalsoum, Erwah; Boisseau, William; Duron, Loïc; Cabral, Dominique; Koskas, Patricia; Benaïssa, Azzedine; Koulakian, Hasmik; Obadia, Michael; Maïer, Benjamin; Weisenburger-Lile, David; Lapergue, Bertrand; Wang, Adrien; Redjem, Hocine; Ciccio, Gabriele; Smajda, Stanislas; Desilles, Jean-Philippe; Mazighi, Mikaël; Ben Maacha, Malek; Akkari, Inès; Zuber, Kevin; Blanc, Raphaël; Raymond, Jean; Piotin, Michel

    2018-01-01

    We aimed to study the intrarater and interrater agreement of clinicians attributing DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores) and DWI-FLAIR (Diffusion-Weighted Imaging-Fluid Attenuated Inversion Recovery) mismatch in patients with acute ischemic stroke referred for mechanical thrombectomy. Eighteen raters independently scored anonymized magnetic resonance imaging scans of 30 participants from a multicentre thrombectomy trial, in 2 different reading sessions. Agreement was measured using Fleiss κ and Cohen κ statistics. Interrater agreement for DWI-ASPECTS was slight (κ=0.17 [0.14-0.21]). Four raters (22.2%) had a substantial (or higher) intrarater agreement. Dichotomization of the DWI-ASPECTS (0-5 versus 6-10 or 0-6 versus 7-10) increased the interrater agreement to a substantial level (κ=0.62 [0.48-0.75] and 0.68 [0.55-0.79], respectively) and more raters reached a substantial (or higher) intrarater agreement (17/18 raters [94.4%]). Interrater agreement for DWI-FLAIR mismatch was moderate (κ=0.43 [0.33-0.57]); 11 raters (61.1%) reached a substantial (or higher) intrarater agreement. Agreement between clinicians assessing DWI-ASPECTS and DWI-FLAIR mismatch may not be sufficient to make repeatable clinical decisions in mechanical thrombectomy. The dichotomization of the DWI-ASPECTS (0-5 versus 0-6 or 0-6 versus 7-10) improved interrater and intrarater agreement, however, its relevance for patients selection for mechanical thrombectomy needs to be validated in a randomized trial. © 2017 American Heart Association, Inc.

  13. Diffusion-weighted and diffusion tensor imaging for pediatric musculoskeletal disorders

    International Nuclear Information System (INIS)

    MacKenzie, John D.; Gonzalez, Leonardo; Hernandez, Andrea; Ruppert, Kai; Jaramillo, Diego

    2007-01-01

    Diffusion-weighted imaging (DWI) is a powerful tool that has recently been applied to evaluate several pediatric musculoskeletal disorders. DWI probes abnormalities of tissue structure by detecting microscopic changes in water mobility that develop when disease alters the organization of normal tissue. DWI provides tissue characterization at a cellular level beyond what is available with other imaging techniques, and can sometimes identify pathology before gross anatomic alterations manifest. These features of early detection and tissue characterization make DWI particularly appealing for probing diseases that affect the musculoskeletal system. This article focuses on the current and future applications of DWI in the musculoskeletal system, with particular attention paid to pediatric disorders. Although most of the applications are experimental, we have emphasized the current state of knowledge and the main research questions that need to be investigated. (orig.)

  14. Utility of diffusion-weighted imaging in the presurgical diagnosis of an infected urachal cyst

    International Nuclear Information System (INIS)

    Chouhan, Manil; Cuckow, Peter; Humphries, Paul D.

    2011-01-01

    Urachal cysts are one of a spectrum of urachal abnormalities that occur following failure of regression of the allantois and presumptive bladder between 4 weeks and 6 weeks of gestation. Infection is the most common complication of this rare congenital anomaly. The nonspecific presentation may mimic other pathological processes, underlining their clinical and radiological significance. Imaging investigations typically include US and CT, both of which are limited in their ability to characterize lesions. We report the case of a 5-year-old presenting with macroscopic haematuria in whom diffusion-weighted MRI (DWI) suggested the diagnosis of an infected urachal cyst, which was confirmed surgically. We discuss the radiological findings in multiple imaging modalities and present the application of DWI in this context as a means of improving the radiological diagnostic yield. (orig.)

  15. Conspicuity of diffuse axonal injury lesions on diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Kinoshita, Toshibumi; Moritani, Toshio; Hiwatashi, Akio; Wang, Henry Z.; Shrier, David A.; Numaguchi, Yuji; Westesson, Per-Lennart A.

    2005-01-01

    Objective: (1) To detect diffuse axonal injury (DAI) lesions by diffusion-weighted imaging (DWI), as compared with fluid-attenuated inversion recovery (FLAIR) imaging and (2) to evaluate hemorrhagic DAI lesions by b 0 images obtained from DWI, as compared with gradient-echo (GRE) imaging. Methods: We reviewed MR images of 36 patients with a diagnosis of DAI. MR imaging was performed 20 h to 14 days (mean, 3.7 days) after traumatic brain injury. We evaluated: (1) conspicuity of lesions on DWI and FLAIR and (2) conspicuity of hemorrhage in DAI lesions on b 0 images and GRE imaging. Results: DWI clearly depicted high-signal DAI lesions. The sensitivity of DWI to lesional conspicuity in DAI lesions was almost equal to that of FLAIR. The sensitivity of b 0 images to identification of hemorrhagic DAI lesions was inferior to that of GRE. Conclusion: DWI is as useful as FLAIR in detecting DAI lesions. GRE imaging is still the superior tool for the evaluation of hemorrhagic DAI

  16. Conspicuity of diffuse axonal injury lesions on diffusion-weighted MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Toshibumi [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States)]. E-mail: kino@grape.med.tottori-u.ac.jp; Moritani, Toshio [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States); Hiwatashi, Akio [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States); Wang, Henry Z. [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States); Shrier, David A. [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States); Numaguchi, Yuji [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States); Westesson, Per-Lennart A. [Department of Radiology, Division of Neuroradiology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY 14642 (United States)

    2005-10-01

    Objective: (1) To detect diffuse axonal injury (DAI) lesions by diffusion-weighted imaging (DWI), as compared with fluid-attenuated inversion recovery (FLAIR) imaging and (2) to evaluate hemorrhagic DAI lesions by b{sub 0} images obtained from DWI, as compared with gradient-echo (GRE) imaging. Methods: We reviewed MR images of 36 patients with a diagnosis of DAI. MR imaging was performed 20 h to 14 days (mean, 3.7 days) after traumatic brain injury. We evaluated: (1) conspicuity of lesions on DWI and FLAIR and (2) conspicuity of hemorrhage in DAI lesions on b{sub 0} images and GRE imaging. Results: DWI clearly depicted high-signal DAI lesions. The sensitivity of DWI to lesional conspicuity in DAI lesions was almost equal to that of FLAIR. The sensitivity of b{sub 0} images to identification of hemorrhagic DAI lesions was inferior to that of GRE. Conclusion: DWI is as useful as FLAIR in detecting DAI lesions. GRE imaging is still the superior tool for the evaluation of hemorrhagic DAI.

  17. The utility of diffusion-weighted MR imaging in differentiation of uterine adenomyosis and leiomyoma

    International Nuclear Information System (INIS)

    Yang Qiong; Zhang Lihua; Su Jing; Liu Jianyu

    2011-01-01

    Purpose: To investigate the value of diffusion-weighted MR imaging (DWI), especially apparent diffusion coefficient (ADC) in the differentiation of uterine adenomyosis and leiomyoma. Materials and methods: 17 patients with uterine leiomyoma and 22 patients with uterine adenomyosis underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging. The ADC values, as well as ADC D-value (defined as the ADC value of high signal intensive foci minus the ADC value of lesion tissues the difference in value), were measured and compared to investigate whether they could help in the differentiation of uterine adenomyosis and leiomyoma. Histopathologic examination was conducted as the golden standard. Results: For high signal intensive foci within the lesions, uterine adenomyosis demonstrated significantly lower mean ADC value than uterine leiomyoma (1.582 vs. 2.122 x 10 -3 mm 2 /s, P = 0.001). For lesion tissues, uterine adenomyosis demonstrated significantly higher mean ADC value than uterine leiomyoma (1.214 vs. 0.967 x 10 -3 mm 2 /s, P = 0.001). However, there was overlap between uterine adenomyosis and leiomyoma in both measurements. Mean ADC D-value was significantly lower in uterine adenomyosis than in uterine leiomyoma (0.369 vs. 1.096 x 10 -3 mm 2 /s, P = 0.000). ADC D-value had no overlap between uterine adenomyosis and leiomyoma. Conclusion: DWI can be applied for the further differentiation of uterine adenomyosis and leiomyoma, in addition to routine MR imaging. ADC D-value may be a more useful tool than ADC value in the differentiation.

  18. The utility of diffusion-weighted MR imaging in differentiation of uterine adenomyosis and leiomyoma

    Energy Technology Data Exchange (ETDEWEB)

    Yang Qiong, E-mail: yangq1112@126.com [Department of Radiology, Peking University Third Hospital, Beijing 100191 (China); Zhang Lihua, E-mail: zhanglh04036@yahoo.com.cn [Department of Radiology, Peking University Third Hospital, Beijing 100191 (China); Su Jing, E-mail: bjmusujing@gmail.com [Department of Pathology, Peking University Health Science Center, Beijing 100191 (China); Liu Jianyu, E-mail: jyliu5791@sina.com [Department of Radiology, Peking University Third Hospital, Beijing 100191 (China)

    2011-08-15

    Purpose: To investigate the value of diffusion-weighted MR imaging (DWI), especially apparent diffusion coefficient (ADC) in the differentiation of uterine adenomyosis and leiomyoma. Materials and methods: 17 patients with uterine leiomyoma and 22 patients with uterine adenomyosis underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging. The ADC values, as well as ADC D-value (defined as the ADC value of high signal intensive foci minus the ADC value of lesion tissues the difference in value), were measured and compared to investigate whether they could help in the differentiation of uterine adenomyosis and leiomyoma. Histopathologic examination was conducted as the golden standard. Results: For high signal intensive foci within the lesions, uterine adenomyosis demonstrated significantly lower mean ADC value than uterine leiomyoma (1.582 vs. 2.122 x 10{sup -3} mm{sup 2}/s, P = 0.001). For lesion tissues, uterine adenomyosis demonstrated significantly higher mean ADC value than uterine leiomyoma (1.214 vs. 0.967 x 10{sup -3} mm{sup 2}/s, P = 0.001). However, there was overlap between uterine adenomyosis and leiomyoma in both measurements. Mean ADC D-value was significantly lower in uterine adenomyosis than in uterine leiomyoma (0.369 vs. 1.096 x 10{sup -3} mm{sup 2}/s, P = 0.000). ADC D-value had no overlap between uterine adenomyosis and leiomyoma. Conclusion: DWI can be applied for the further differentiation of uterine adenomyosis and leiomyoma, in addition to routine MR imaging. ADC D-value may be a more useful tool than ADC value in the differentiation.

  19. The utility of diffusion-weighted MR imaging in cervical cancer

    International Nuclear Information System (INIS)

    Chen Jianyu; Zhang Yun; Liang Biling; Yang Zehong

    2010-01-01

    Purpose: To investigate the value of diffusion-weighted MR imaging (DWI) in detection of cervical cancer, and to determine the diagnostic accuracy of apparent diffusion coefficient (ADC) values for evaluating cervical cancer before and after chemoradiotherapy. Materials and methods: Thirty-three patients with cervical squamous carcinoma and 20 patients with other pelvic abnormalities underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging. The ADC values of normal cervical tissue, cervical area before and after chemoradiotherapy were measured and compared. Receiver operating characteristic (ROC) analysis was employed to investigate whether ADC values could help in discrimination among normal cervical tissue, cervical cancer before and after therapy, and to obtain the optimal ADC threshold value. Results: Cervical cancer lesion demonstrated obviously hyperintensity on DWI images. The mean ADC value of cervical carcinoma (1.110 ± 0.175 x 10 -3 mm 2 /s) was significantly lower than that of normal cervical tissue (1.593 ± 0.151 x 10 -3 mm 2 /s) (P -3 mm 2 /s) was significantly higher than that before therapy (1.013 ± 0.094 x 10 -3 mm 2 /s) (P -3 mm 2 /s, between cervical area before and after therapy was 1.255 x 10 -3 mm 2 /s, between normal cervical tissue and cervical area after therapy was 1.525 x 10 -3 mm 2 /s. The sensitivity and specificity were 100% and 84.8%, 95.5% and 100%, 70% and 81.8%, respectively. Conclusion: DWI can be applied for the detection of cervical cancer because of its superior disease contrast with normal tissue. The measurement of the ADC values can be a useful tool to monitor the response to therapy for cervical carcinoma.

  20. Functional imaging of parotid glands: Diffusion-weighted echo-planar MRI before and after stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Habermann, C.R.; Cramer, M.C.; Gossrau, P.; Adam, G. [University Hospital Hamburg-Eppendorf (Germany). Department of Diagnostic and Interventional Radiology; Graessner, J. [Siemens AG, Hamburg (Germany). Medical Solutions; Reitmeier, F.; Jaehne, M. [University Hospital Hamburg-Eppendorf (Germany). Department of Oto-, Rhino-, Laryngology; Fiehler, J. [University Hospital Hamburg-Eppendorf (Germany). Department of Neuroradiology; Schoder, V. [University Hospital Hamburg-Eppendorf (Germany). Institute for Medical Biometry and Epidemiology

    2004-10-01

    Purpose: To investigate the feasibility of diffusion-weighted (DW) echo-planar imaging (EPI) for measuring different functional conditions of the parotid gland and to compare different measurement approaches. Materials and Methods: Parotid glands of 27 healthy volunteers were examined with a DW EPI sequence (TR 1,500 msec, TE 77 msec, field-of-view 250 x 250 mm, pixel size 2.10 x 1.95 mm, section thickness 5 mm) before and after oral stimulation with commercially available lemon juice. The b factors used were 0, 500, and 1,000 sec/mm{sup 2}. Apparent diffusion coefficient (ADC) maps were digitally transferred to MRIcro (Chris Rorden, University of Nottingham, Great Britain) and evaluated with a manually placed circular region of interest (ROI) containing 100-200 pixel. Additional ROIs including the entire parotid gland were placed on either side. The results of both measurements were compared, using the Student's t test based on the median ADC values for each person. A two-tailed p-value of less than.05 was determined to indicate statistical significance. To compare both measurement approaches, the Pearson's correlation coefficient (r) was calculated. Results: Diffusion-weighted echo-planar MR imaging successfully visualized the parotid gland of all volunteers. In a first step, the median ADC value per person was computed. Using ROIs of 100-200 pixels, the mean was calculated to be 1.08 x 10{sup -3} mm{sup 2}/sec{+-}0.12 x 10{sup -3} mm{sup 2}/sec for both parotid glands prior to simulation. After stimulation, the mean ADC was measured at 1.15 x 10{sup -3} mm{sup 2}/sec{+-}0.11 x 10{sup -3} mm{sup 2}/sec for both parotid glands. Evaluating the entire parotid gland, the ADC was 1.12 x 10{sup -3} mm{sup 2}/sec{+-}0.08 x 10{sup -3} mm{sup 2}/sec prior to simulation, whereas the ADC increased to 1.18 x 10{sup -3} mm{sup 2}/sec{+-}0.09 x 10{sup -3} mm{sup 2}/sec after simulation with lemon juice. For both types of measurements, the increase in ADC after

  1. Diffusion-weighted imaging in the evaluation of odontogenic cysts and tumours.

    Science.gov (United States)

    Srinivasan, K; Seith Bhalla, A; Sharma, R; Kumar, A; Roychoudhury, A; Bhutia, O

    2012-10-01

    The differentiation between keratocystic odontogenic tumour (KCOT) and other cystic/predominantly cystic odontogenic tumours is difficult on conventional CT and MR sequences as there is overlap in the imaging characteristics of these lesions. The purpose of this study was to evaluate the role of diffusion-weighted imaging (DWI) and to assess the performance of apparent diffusion coefficients (ADCs) in the differential diagnosis of odontogenic cysts and tumours. 20 patients with odontogenic cysts and tumours of the maxillomandibular region were examined with DWI. Diffusion-weighted images were obtained with a single-shot echoplanar technique with b-values of 0, 500 and 1000 s mm(-2). An ADC map was obtained at each slice position. The cystic areas of ameloblastoma (n=10) showed free diffusion with a mean ADC value of 2.192±0.33×10(-3) mm(2) s(-1), whereas the solid areas showed restricted diffusion with a mean ADC value of 1.041±0.41×10(-3) mm(2) s(-1). KCOT (n=5) showed restricted diffusion with a mean ADC value of 1.019±0.07×10(-3) mm(2) s(-1). There was a significant difference between the ADC values of KCOT and cystic ameloblastoma (p<0.01, Mann-Whitney U-test). The cut-off with which KCOT and predominantly cystic ameloblastomas were optimally differentiated was 2.013×10(-3) mm(2) s(-1), which yielded 100% sensitivity and 100% specificity. DWI can be used to differentiate KCOT from cystic (or predominantly cystic) odontogenic tumours.

  2. The contribution of diffusion-weighted MR imaging to distinguishing typical from atypical meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Hakyemez, Bahattin [Uludag University School of Medicine, Department of Radiology, Gorukle, Bursa (Turkey); Bursa State Hospital, Department of Radiology, Bursa (Turkey); Yildirim, Nalan; Gokalp, Gokhan; Erdogan, Cuneyt; Parlak, Mufit [Uludag University School of Medicine, Department of Radiology, Gorukle, Bursa (Turkey)

    2006-08-15

    Atypical/malignant meningiomas recur more frequently then typical meningiomas. In this study, the contribution of diffusion-weighted MR imaging to the differentiation of atypical/malignant and typical meningiomas and to the determination of histological subtypes of typical meningiomas was investigated. The study was performed prospectively on 39 patients. The signal intensity of the lesions was evaluated on trace and apparent diffusion coefficient (ADC) images. ADC values were measured in the lesions and peritumoral edema. Student's t-test was used for statistical analysis. P<0.05 was considered statistically significant. Mean ADC values in atypical/malignant and typical meningiomas were 0.75{+-}0.21 and 1.17{+-}0.21, respectively. Mean ADC values for subtypes of typical meningiomas were as follows: meningothelial, 1.09{+-}0.20; transitional, 1.19{+-}0.07; fibroblastic, 1.29{+-}0.28; and angiomatous, 1.48{+-}0.10. Normal white matter was 0.91{+-}0.10. ADC values of typical meningiomas and atypical/malignant meningiomas significantly differed (P<0.001). However, the difference between peritumoral edema ADC values was not significant (P>0.05). Furthermore, the difference between the subtypes of typical meningiomas and atypical/malignant meningiomas was significant (P<0.001). Diffusion-weighted MR imaging findings of atypical/malignant meningiomas and typical meningiomas differ. Atypical/malignant meningiomas have lower intratumoral ADC values than typical meningiomas. Mean ADC values for peritumoral edema do not differ between typical and atypical meningiomas. (orig.)

  3. Diffusion weighted imaging and diffusion tensor imaging in the evaluation of transplanted kidneys

    International Nuclear Information System (INIS)

    Palmucci, Stefano; Cappello, Giuseppina; Attinà, Giancarlo; Foti, Pietro Valerio; Siverino, Rita Olivia Anna; Roccasalva, Federica; Piccoli, Marina; Sinagra, Nunziata; Milone, Pietro; Veroux, Massimiliano; Ettorre, Giovanni Carlo

    2015-01-01

    The aim of this study is to investigate the relation between renal indexes and functional MRI in a population of kidney transplant recipients who underwent MR with diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) of the transplanted graft. Study population included 40 patients with single kidney transplant. The patients were divided into 3 groups, on the basis of creatinine clearance (CrCl) values calculated using Cockcroft-Gault formula: group A, including patients with normal renal function (CrCl ≥ 60 mL/min); group B, which refers to patients with moderate renal impairment (CrCl > 30 but <60 mL/min); and, finally, group C, which means severe renal deterioration (CrCl ≤ 30 mL/min). All patients were investigated with a 1.5 Tesla MRI scanner, acquiring DWI and DTI sequences. A Mann–Whitney U test was adopted to compare apparent diffusion coefficients (ADCs) and fractional anisotropy (FA) measurements between groups. Receiver operating characteristic (ROC) curves were created for prediction of normal renal function (group A) and renal failure (group C). Pearson correlation was performed between renal clearance and functional imaging parameter (ADC and FA), obtained for cortical and medullar regions. Mann–Whitney U test revealed a highly significant difference (p < 0.01) between patients with low CrCl (group C) and normal CrCl (group A) considering both medullar ADC and FA and cortical ADC. Regarding contiguous groups, the difference between group B and C was highly significant (p < 0.01) for medullar ADC and significant (p < 0.05) for cortical ADC and medullar FA. No difference between these groups was found considering cortical FA. Analyzing groups A and B, we found a significant difference (p < 0.05) for medullar both ADC and FA, while no difference was found for cortical ADC and FA. Strongest Pearson correlation was found between CrCl and medullar ADC (r = 0.65). For predicting normal renal function or severe renal impairment, highest

  4. Assessment of the responses to neoadjuvant chemotherapy of osteosarcoma by diffusion-weighted MR image: initial results

    International Nuclear Information System (INIS)

    Shu Min; Du Lianjun; Ding Xiaoyi; Lu Yong; Yan Ling; Jiang Hao; Chen Kemin

    2009-01-01

    Objective: To determine the utility of diffusion-weighted magnetic resonance imaging (MR DWI) in detecting tumor necrosis with histological correlation after neoadjuvant chemotherapy. Methods: Conventional MRI and DWI were obtained from 36 patients with histological proven osteosarcoma. Magnetic resonance examinations were performed in all patients before and after 4 cycles of preoperative neoadjuvant chemotherapy. Apparent diffusion coefficients (ADC) were calculated. The degree of tumor necrosis was assessed using the histological Huvos classification after chemotherapy. t-test was performed for testing changes in ADC value between the 2 groups. P value less than 0.05 were considered as a statistically significant difference. Results: The differences in ADC between viable [(1.06 ± 0.30)x10 -3 mm 2 /s] and necrotic [(2.39 ± 0.44)x10 -3 mm 2 /s] tumor were significant (t = 3.515, P -3 mm 2 /s to (2.27 ± 0.20)x10 -3 mm 2 s, the corresponding value in poor responses was increased from (1.45 ± 0.11)x10 -3 mm 2 /s to (1.83 ± 0.16)x10 -3 mm 2 /s. There was significant difference in changes of ADC values between good responses and poor responses (t = 4.981, P < 0.01). Conclusion: Diffusion-weighted MRI permits recognition of tumor necrosis induced by chemotherapy in osteosarcoma. DWI is correlated directly with tumor necrosis. They have potential utility in evaluating the preoperative chemotherapy response in patients with primary osteosarcoma. (authors)

  5. Diffusion-weighted imaging in chronic Behcet patients with and without neurological findings

    International Nuclear Information System (INIS)

    Baysal, T.; Dogan, M.; Bulut, T.; Sarac, K.; Karlidag, R.; Ozisik, H.I.; Baysal, O.

    2005-01-01

    Our aim was to investigate whether neurological impairment in chronic Behcet's disease (BD) patients with normal appearing brain can be assessed by means of diffusion-weighted imaging (DWI). The averaged apparent diffusion coefficient (ADC) values were calculated in 22 different radiologically normal appearing brain regions in 32 patients with and without neurological findings and 20 control subjects. The ADC values in bilateral frontal, temporal and occipital normal appearing white matter were significantly higher in the patient groups compared with the control subjects (p<0.05). In these brain regions, DWI revealed differences in the ADC values between patients with neurological findings (including symptomatic and neuro-Behcet patients) and the asymptomatic patient group. The similarity of the ADC values of patients without symptoms to those of the control group allowed clear discrimination between patients with and without neurological findings. DWI may serve to assess subclinical neurological involvement in BD, even when structural changes are absent. (orig.)

  6. Diffusion-weighted imaging and cognition in the leukoariosis and disability in the elderly study

    DEFF Research Database (Denmark)

    Schmidt, Reinhold; Ropele, Stefan; Ferro, José

    2010-01-01

    : Increasing WMH scores were associated with a higher frequency of hypertension, a greater WMH volume, more brain atrophy, worse overall cognitive performance, and changes in ADC. We found strong associations between the peak height of the ADC histogram of whole-brain tissue and NABT with memory performance......BACKGROUND AND PURPOSE: The mechanisms by which leukoariosis impacts on clinical and cognitive functions are not yet fully understood. We hypothesized that ultrastructural abnormalities of the normal-appearing brain tissue (NABT) assessed by diffusion-weighted imaging played a major and independent...... without previous disability. WMH severity was rated according to the Fazekas score. Multivariate regression analysis served to assess correlations of histogram metrics of the apparent diffusion coefficient (ADC) of whole-brain tissue, NABT, and of the mean ADC of WMH with cognitive functions. RESULTS...

  7. Diffusion-weighted imaging and cognition in the leukoariosis and disability in the elderly study

    DEFF Research Database (Denmark)

    Schmidt, Reinhold; Ropele, Stefan; Ferro, José

    2010-01-01

    : Increasing WMH scores were associated with a higher frequency of hypertension, a greater WMH volume, more brain atrophy, worse overall cognitive performance, and changes in ADC. We found strong associations between the peak height of the ADC histogram of whole-brain tissue and NABT with memory performance......, executive dysfunction, and speed, which remained after adjustment for WMH lesion volume and brain atrophy and were consistent among centers. No such association was seen with the mean ADC of WMH. CONCLUSIONS: Ultrastructural abnormalities of NABT increase with WMH severity and have a strong and independent......BACKGROUND AND PURPOSE: The mechanisms by which leukoariosis impacts on clinical and cognitive functions are not yet fully understood. We hypothesized that ultrastructural abnormalities of the normal-appearing brain tissue (NABT) assessed by diffusion-weighted imaging played a major and independent...

  8. Differential diagnostic value of diffusion weighted imaging on brain abscess and necrotic or cystic brain tumors

    International Nuclear Information System (INIS)

    Zhang Xiaoya; Yin Jie; Wang Kunpeng; Zhang Jiandang; Liang Biling

    2009-01-01

    Objective: To investigate the value of diffusion weighted imaging (DWI)on brain abscess and necrotic or cystic brain tumors. Methods: 27 cases with brain abscesses and 33 cases with necrotic or cystic brain tumors (gliomas or metastases) were performed conventional MRI and DWI. Apparent diffusion coefficient (ADC) of region of interest (ROI) was measured and statistically tested. Sensitivity and specificity were calculated and compared with conventional MR and DWI. Results: Hyperintensity signal was seen on most brain abscesses. All necrotic or cystic brain tumors showed hypointensity signal on DWI. There was statistical significance on ADC of them. The sensitivity and specificity of conventional MRI was lower than that of DWI. Conclusion: DWI and ADC were useful in distinguishing brain abscessed from necrotic or cystic brain tumors, which was important in addition to conventional MRI. (authors)

  9. Diffusion-weighted imaging in transient global amnesia exposes the CA1 region of the hippocampus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ho Yun; Kim, Jae Hyoung; Weon, Young-Cheol; Youn, Sung Won; Kim, Sung Hyun [Seoul National University Bundang Hospital, Department of Radiology, Seoul National University College of Medicine, Seongnam-si (Korea); Lee, Jung Seok; Kim, Sang Yun [Seoul National University Bundang Hospital, Department of Neurology, Seoul National University College of Medicine, Seongnam-si (Korea)

    2007-06-15

    Transient global amnesia (TGA) is characterized by a sudden onset of anterograde amnesia without alteration of consciousness or personal identity. Interestingly, recent studies have reported a high frequency of small high-signal abnormalities in the hippocampus with diffusion-weighted (DW) imaging, and ischemia has been proposed as an etiology of TGA. We hypothesized that TGA lesions occur preferentially in the CA1 region of the hippocampus, known to be susceptible to ischemia. Over a 30-month period 34 patients with TGA underwent MRI including DW imaging within 4 days of symptom onset. Patients with high-signal abnormalities in the hippocampus on the initial DW images underwent subsequent DW and T2-weighted imaging in the coronal plane to identify the precise lesion locations. Fourteen patients had small (1-3 mm) high-signal abnormalities in the hippocampus unilaterally on DW images. One of these patients had two lesions in one hippocampus and therefore in total 15 lesions were identified: four in the hippocampal head, and 11 in the body. Eleven lesions in ten patients with available coronal images were clearly demonstrated on both coronal DW and T2-weighted images and were localized to the lateral portion of the hippocampus, corresponding to the CA1 region. Lesions associated with TGA were localized exclusively to the lateral portion of the hippocampus corresponding to the CA1 region. This finding supports the ischemic etiology of TGA; however, the pathophysiological mechanism involved requires further study. (orig.)

  10. Diffusion-weighted imaging in transient global amnesia exposes the CA1 region of the hippocampus

    International Nuclear Information System (INIS)

    Lee, Ho Yun; Kim, Jae Hyoung; Weon, Young-Cheol; Youn, Sung Won; Kim, Sung Hyun; Lee, Jung Seok; Kim, Sang Yun

    2007-01-01

    Transient global amnesia (TGA) is characterized by a sudden onset of anterograde amnesia without alteration of consciousness or personal identity. Interestingly, recent studies have reported a high frequency of small high-signal abnormalities in the hippocampus with diffusion-weighted (DW) imaging, and ischemia has been proposed as an etiology of TGA. We hypothesized that TGA lesions occur preferentially in the CA1 region of the hippocampus, known to be susceptible to ischemia. Over a 30-month period 34 patients with TGA underwent MRI including DW imaging within 4 days of symptom onset. Patients with high-signal abnormalities in the hippocampus on the initial DW images underwent subsequent DW and T2-weighted imaging in the coronal plane to identify the precise lesion locations. Fourteen patients had small (1-3 mm) high-signal abnormalities in the hippocampus unilaterally on DW images. One of these patients had two lesions in one hippocampus and therefore in total 15 lesions were identified: four in the hippocampal head, and 11 in the body. Eleven lesions in ten patients with available coronal images were clearly demonstrated on both coronal DW and T2-weighted images and were localized to the lateral portion of the hippocampus, corresponding to the CA1 region. Lesions associated with TGA were localized exclusively to the lateral portion of the hippocampus corresponding to the CA1 region. This finding supports the ischemic etiology of TGA; however, the pathophysiological mechanism involved requires further study. (orig.)

  11. MR diffusion weighted imaging detecting cerebral infarction: a meta-analysis

    International Nuclear Information System (INIS)

    Yang Junle; Xu Min; Wang Peng; Zhang Qiujuan; Guo Youmin; Liu Min

    2008-01-01

    Objective: To determine the diagnostic value of diffusion-weighted imaging(DWI) in hyperacute and acute cerebral infarction by using Meta-analysis. Methods: Based on validity criteria for diagnostic research published by the Cochrane Methods Group on Screening and Diagnostic, studies in English and Chinese from 1997 to 2007 were selected from Medline, Cochrane, Springer, Ovid, Elsevier, LWW and CNKI( China National Knowledge Infrastructure). The characteristics of the included articles were appraised and extracted. Statistical analysis was performed with the software Meta-test 0.6 and Comprehensive meta-analysis 2.0. Heterogeneity of the included articles was tested, which was used to select proper effect model to calculate pooled weighted values of sensitivity and specificity and the corresponding 95% CI. Summary receiver operating characteristic (SROC) curve was performed and the area under the curve (Az) was calculated. Publication bias was analyzed by Funnel Plot in Comprehensive Meta- analysis 2.0. A sensitivity analysis was performed. Results: Twelve articles meeting inclusion criteria were analyzed for the value of DWI in hyperacute cerebral infarction. The pooled sensitivity, specificity and diagnostic odds ratio was 92%, 87%, 180.37 respectively, Az=0.9717. Novice is a main factor for total diagnostic effect (Q=4.34, P>0.05). Non-asymmetric funnel plot suggested the publication bias. Fifteen articles meeting inclusion criteria were analyzed for the value of DWI in both hyperacute and acute cerebral infarction (≤ 24 h). The pooled sensitivity, specificity diagnostic odds ratio was 92%, 91%, 623.62 respectively, Az=0.9659. Fixed effects model used in Meta-analysis for database suggested homogeneity (Q=2.70,P>0.05). Nonasymmetric funnel plot suggested the publication bias. Conclusions As a noninvasive method, diffusion-weighted imaging is valuable in detecting hyperacute and acute cerebral infarction. More support from multi-center prospective researches is

  12. Diffusion-Weighted Imaging for Predicting New Compression Fractures Following Percutaneous Vertebroplasty

    International Nuclear Information System (INIS)

    Sugimoto, T.

    2008-01-01

    Background: Percutaneous vertebroplasty (PVP) is a technique that structurally stabilizes a fractured vertebral body. However, some patients return to the hospital due to recurrent back pain following PVP, and such pain is sometimes caused by new compression fractures. Purpose: To investigate whether the apparent diffusion coefficient (ADC) of adjacent vertebral bodies as assessed by diffusion-weighted imaging before PVP could predict the onset of new compression fractures following PVP. Material and Methods: 25 patients with osteoporotic compression fractures who underwent PVP were enrolled in this study. ADC was measured for 49 vertebral bodies immediately above and below each vertebral body injected with bone cement before and after PVP. By measuring ADC for each adjacent vertebral body, ADC was compared between vertebral bodies with a new compression fracture within 1 month and those without new compression fractures. In addition, the mean ADC of adjacent vertebral bodies per patient was calculated. Results: Mean preoperative ADC for the six adjacent vertebral bodies with new compression fractures was 0.55x10 -3 mm 2 /s (range 0.36-1.01x10 -3 mm 2 /s), and for the 43 adjacent vertebral bodies without new compression fractures 0.20x10 -3 mm 2 /s (range 0-0.98x10 -3 mm 2 /s) (P -3 mm 2 /s (range 0.21-1.01x10 -3 mm 2 /s), and that for the 19 patients without new compression fractures 0.17x10 -3 mm 2 /s (range 0.01-0.43x10 -3 mm 2 /s) (P<0.001). Conclusion: The ADC of adjacent vertebral bodies as assessed by diffusion-weighted imaging before PVP might be one of the predictors for new compression fractures following PVP

  13. Diffusion-weighted MR imaging of pleural fluid: differentiation of transudative vs exudative pleural effusions

    International Nuclear Information System (INIS)

    Baysal, T.; Bulut, T.; Dusak, A.; Dogan, M.; Goekirmak, M.; Kalkan, S.

    2004-01-01

    The aim of this study was to evaluate the ability of diffusion-weighted MRI in differentiating transudative from exudative pleural effusions. Fifty-seven patients with pleural effusion were studied. Diffusion-weighted imaging (DWI) was performed with an echo-planar imaging (EPI) sequence (b values 0, 1000 s/mm 2 ) in 52 patients. The apparent diffusion coefficient (ADC) values were reconstructed from three different regions. Subsequently, thoracentesis was performed and the pleural fluid was analyzed. Laboratory results revealed 20 transudative and 32 exudative effusions. Transudates had a mean ADC value of 3.42±0.76 x 10 -3 mm 2 /s. Exudates had a mean ADC value of 3.18±1.82 x 10 -3 mm 2 /s. The optimum cutoff point for ADC values was 3.38 x 10 -3 mm 2 /s with a sensitivity of 90.6% and specificity of 85%. A significant negative correlation was seen between ADC values and pleural fluid protein, albumin concentrations and lactate dehydrogenase (LDH) measurements (r=-0.69, -0.66, and -0.46, respectively; p<0.01). The positive predictive value, negative predictive value, and diagnostic accuracy of ADC values were determined to be 90.6, 85, and 88.5%, respectively. The application of diffusion gradients to analyze pleural fluid may be an alternative to the thoracentesis. Non-invasive characterization of a pleural effusion by means of DWI with single-shot EPI technique may obviate the need for thoracentesis with its associated patient morbidity. (orig.)

  14. Diffusion-weighted echo planar imaging in patients with recent myocardial infarction

    International Nuclear Information System (INIS)

    Deux, Jean-Francois; Maatouk, Mezri; Luciani, Alain; Lenczner, Gregory; Mayer, Julie; Kobeiter, Hicham; Rahmouni, Alain; Vignaud, Alexandre; Lim, Pascal; Dubois-Rande, Jean-Luc

    2011-01-01

    To evaluate a diffusion-weighted (DW) black blood MR sequence for the detection of myocardium signal abnormalities in patients with recent myocardial infarction (MI). A DW black blood EPI sequence was acquired at 1.5 T in 12 patients with recent MI. One slice per patient was acquired with b = 0 and b = 50 s/mm 2 . A standard short tau inversion recovery (STIR) T2-weighted sequence was acquired at the same level. Viability was assessed with delayed-enhancement sequences. Images were analyzed qualitatively and quantitatively. A non parametric Wilcoxon test was used for statistical analysis, with a significance level of P <.05. The mean quality of blood suppression was higher on DW EPI images than on STIR T2-weighted images (3.9 ± 0.3 and 3.0 ± 0.7, respectively; P = 0.01). Myocardial high signal areas were detected in respectively 100% (12/12) and 67% (8/12) of the patients on DW EPI and STIR T2-weighted images. The four patients (33%) with false-negative STIR T2 findings all had high signal areas on DW EPI images corresponding to the location of the MI on the delayed-enhanced images. DW EPI sequences are a feasible alternative to standard STIR T2-weighted sequences for detecting myocardium high signal areas in patients with recent MI. (orig.)

  15. Purulent meningitis with unusual diffusion-weighted MRI findings

    International Nuclear Information System (INIS)

    Abe, M.; Takayama, Y.; Yamashita, H.; Noguchi, M.; Sagoh, T.

    2002-01-01

    We describe unusual findings obtained by diffusion-weighted magnetic resonance imaging (MRI) in a patient with acute purulent meningitis caused by penicillin-resistant Streptococcus pneumoniae. Along cerebral convexities and the Sylvian fissure, multiple small intense lesions showed high signal intensity in these sequences. This may be the first report of diffusion-weighted in purulent meningitis

  16. A radiological study of cerebral white matter lesions in patients with dementia using diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Shindo, Hiroaki; Hanyu, Haruo; Kakizaki, Dai; Abe, Kimihiko; Takasaki, Masaru

    1999-01-01

    We investigated the changes in water diffusion in the cerebral white matter and the corpus callosum in 12 patients with Binswanger's disease (BD), and 19 patients with Alzheimer's Disease (AD), including 12 without (AD-) and 7 with periventricular hyperintensity (PVH) lesions (AD+), using diffusion-weighted magnetic resonance imaging (MRI). Apparent diffusion coefficients (ADCs) in the anterior and posterior white matter were significantly higher in patients with BD and AD than in 12 age-matched controls. The ADCs were significantly higher in AD (+) than in AD (-) patients. Anisotropic ratios (ARs), defined as diffusion restricted perpendicular to the direction of the nerve fibers, were significantly higher in BD and AD (+) patients, and even in AD (-) patients, than in the controls. ARs in the anterior white matter were significantly higher in BD than in AD (+), while in the posterior white matter the ratios were significantly higher in AD (+) rather than BD patients. The ADCs and ARs in the genu of the corpus callosum were significantly higher in patients with BD and AD (+) compared to the control subjects, while ADCs and ARs in the splenium were significantly higher in patients with AD (+) and AD (-) than in those with BD. These results suggest that mild myelin loss occurs in AD patients even in apparently normal white matter and in the splenium of the corpus callosum. A definite loss of myelin and axons, including incomplete infarction, occurs preferentially in anterior white matter in BD, while in posterior white matter in AD (+), as seen on T2-weighted images as PVH. Studies with diffusion-weighted MRI may allow the characterization of different pathological processes and enable the demonstration of underlying white matter lesion in patients with dementia that cannot be visualized by conventional MRI. (author)

  17. Diffusion Weighted Imaging of the Uterus: Regional ADC Variation with Oral Contraceptive Usage and Comparison with Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Messiou, Christina; Morgan, Veronica A.; Silva, Sonali S. de; Souza, Nandita M. de (Cancer Research UK Clinical Magnetic Resonance Research Group, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Surrey (United Kingdom)); Ind, Thomas E. (Dept. of Gynaecology and Obstetrics, St George' s Hospital NHS Trust, London (United Kingdom))

    2009-07-15

    Background: There is growing interest in diffusion weighted magnetic resonance imaging (MRI) of cervical carcinoma but normal uterine appearances and effects of the oral contraceptive pill (OCP) have not been described. Purpose: To establish apparent diffusion coefficient (ADC) values for normal regions of uterus, determine the effect of the OCP on these values, and compare them with ADCs from cervical cancer. Material and Methods: Twenty-seven premenopausal women (19 taking the OCP) with cervical intraepithelial neoplasia (CIN) were studied with T2W and diffusion weighted MRI (DW-MRI). Regions of interest were drawn on ADC maps by visual matching with T2W images on different zones of the uterus and values compared between women not taking and taking the OCp.A further group of 25 women with clinically obvious tumors of the cervix were also studied with T2W and DW-MRI and ADC values of tumor were compared with ADC values of cervical epithelium and stroma. Results: The ADC values of adjacent zones of the uterus and cervix were significantly different from one another (P<0.001). The junctional zone was seen as a band of restricted diffusion between endometrium and outer myometrium. The ADC value of the junctional zone of the uterus was significantly greater (P<0.001) in patients taking the OCP than those patients not taking the OCp.There was no significant affect of the OCP on the ADC values of other uterine zones. Conclusion: The zonal anatomy of the uterus is well demonstrated by DW-MRI with hormonal effects secondary to the OCP affecting junctional zone alone. ADC of cervical tumor is significantly different to cervical epithelium and stroma indicating a role in cervical cancer detection and local staging

  18. Diffusion Weighted Imaging of the Uterus: Regional ADC Variation with Oral Contraceptive Usage and Comparison with Cervical Cancer

    International Nuclear Information System (INIS)

    Messiou, Christina; Morgan, Veronica A.; Silva, Sonali S. de; Souza, Nandita M. de; Ind, Thomas E.

    2009-01-01

    Background: There is growing interest in diffusion weighted magnetic resonance imaging (MRI) of cervical carcinoma but normal uterine appearances and effects of the oral contraceptive pill (OCP) have not been described. Purpose: To establish apparent diffusion coefficient (ADC) values for normal regions of uterus, determine the effect of the OCP on these values, and compare them with ADCs from cervical cancer. Material and Methods: Twenty-seven premenopausal women (19 taking the OCP) with cervical intraepithelial neoplasia (CIN) were studied with T2W and diffusion weighted MRI (DW-MRI). Regions of interest were drawn on ADC maps by visual matching with T2W images on different zones of the uterus and values compared between women not taking and taking the OCp.A further group of 25 women with clinically obvious tumors of the cervix were also studied with T2W and DW-MRI and ADC values of tumor were compared with ADC values of cervical epithelium and stroma. Results: The ADC values of adjacent zones of the uterus and cervix were significantly different from one another (P<0.001). The junctional zone was seen as a band of restricted diffusion between endometrium and outer myometrium. The ADC value of the junctional zone of the uterus was significantly greater (P<0.001) in patients taking the OCP than those patients not taking the OCp.There was no significant affect of the OCP on the ADC values of other uterine zones. Conclusion: The zonal anatomy of the uterus is well demonstrated by DW-MRI with hormonal effects secondary to the OCP affecting junctional zone alone. ADC of cervical tumor is significantly different to cervical epithelium and stroma indicating a role in cervical cancer detection and local staging

  19. In vivo high angular resolution diffusion-weighted imaging of mouse brain at 16.4 Tesla.

    Directory of Open Access Journals (Sweden)

    Othman I Alomair

    Full Text Available Magnetic Resonance Imaging (MRI of the rodent brain at ultra-high magnetic fields (> 9.4 Tesla offers a higher signal-to-noise ratio that can be exploited to reduce image acquisition time or provide higher spatial resolution. However, significant challenges are presented due to a combination of longer T1 and shorter T2/T2* relaxation times and increased sensitivity to magnetic susceptibility resulting in severe local-field inhomogeneity artefacts from air pockets and bone/brain interfaces. The Stejskal-Tanner spin echo diffusion-weighted imaging (DWI sequence is often used in high-field rodent brain MRI due to its immunity to these artefacts. To accurately determine diffusion-tensor or fibre-orientation distribution, high angular resolution diffusion imaging (HARDI with strong diffusion weighting (b >3000 s/mm2 and at least 30 diffusion-encoding directions are required. However, this results in long image acquisition times unsuitable for live animal imaging. In this study, we describe the optimization of HARDI acquisition parameters at 16.4T using a Stejskal-Tanner sequence with echo-planar imaging (EPI readout. EPI segmentation and partial Fourier encoding acceleration were applied to reduce the echo time (TE, thereby minimizing signal decay and distortion artefacts while maintaining a reasonably short acquisition time. The final HARDI acquisition protocol was achieved with the following parameters: 4 shot EPI, b = 3000 s/mm2, 64 diffusion-encoding directions, 125×150 μm2 in-plane resolution, 0.6 mm slice thickness, and 2h acquisition time. This protocol was used to image a cohort of adult C57BL/6 male mice, whereby the quality of the acquired data was assessed and diffusion tensor imaging (DTI derived parameters were measured. High-quality images with high spatial and angular resolution, low distortion and low variability in DTI-derived parameters were obtained, indicating that EPI-DWI is feasible at 16.4T to study animal models of white

  20. Diffusion kurtosis imaging of the liver at 3 Tesla: in vivo comparison to standard diffusion-weighted imaging.

    Science.gov (United States)

    Budjan, Johannes; Sauter, Elke A; Zoellner, Frank G; Lemke, Andreas; Wambsganss, Jens; Schoenberg, Stefan O; Attenberger, Ulrike I

    2018-01-01

    Background Functional techniques like diffusion-weighted imaging (DWI) are gaining more and more importance in liver magnetic resonance imaging (MRI). Diffusion kurtosis imaging (DKI) is an advanced technique that might help to overcome current limitations of DWI. Purpose To evaluate DKI for the differentiation of hepatic lesions in comparison to conventional DWI at 3 Tesla. Material and Methods Fifty-six consecutive patients were examined using a routine abdominal MR protocol at 3 Tesla which included DWI with b-values of 50, 400, 800, and 1000 s/mm 2 . Apparent diffusion coefficient maps were calculated applying a standard mono-exponential fit, while a non-Gaussian kurtosis fit was used to obtain DKI maps. ADC as well as Kurtosis-corrected diffusion ( D) values were quantified by region of interest analysis and compared between lesions. Results Sixty-eight hepatic lesions (hepatocellular carcinoma [HCC] [n = 25]; hepatic adenoma [n = 4], cysts [n = 18]; hepatic hemangioma [HH] [n = 18]; and focal nodular hyperplasia [n = 3]) were identified. Differentiation of malignant and benign lesions was possible based on both DWI ADC as well as DKI D-values ( P values were in the range of 0.04 to < 0.0001). Conclusion In vivo abdominal DKI calculated using standard b-values is feasible and enables quantitative differentiation between malignant and benign liver lesions. Assessment of conventional ADC values leads to similar results when using b-values below 1000 s/mm 2 for DKI calculation.

  1. MR findings of primary bone lymphoma in a 15-year-old girl: emphasis on diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Kevin M.; Kim, Hee Kyung; Emery, Kathleen H. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Stanek, Jerzy [Cincinnati Children' s Hospital Medical Center, Department of Pathology, Cincinnati, OH (United States)

    2011-05-15

    We report a case of primary bone lymphoma (PBL) in a 15-year-old girl assessed by MR imaging with diffusion-weighted imaging (DWI). DWI has been shown to help characterize the cellularity of solid tumors and this case correlates well with previous data. (orig.)

  2. Comparison of whole body MR diffusion weighted imaging and skeletal scintigraphy in detecting bone metastasis

    International Nuclear Information System (INIS)

    Xu Xian; Ma Lin; Zhang Jinshan; Cai Youquan; Cheng Liuquan; Guo Xinggao; Xu Baixuan

    2008-01-01

    Objective: To evaluate the application of whole body MR diffusion weighted imaging (DWI) in the detection of bone metastasis using skeletal scintigraphy as the reference. Methods: Forty-two healthy volunteers and 38 patients with malignant tumors were enrolled in our study. All the patients received MR examination and skeletal scintigraphy within one week. MR examination was performed on GE signa 3.0T MR scanner using a build-in body coil. The skeletal system was divided into eight regions and the images of the whole body MR DWI and skeletal scintigraphy were reviewed to compare the two modalities patient by patient and region by region. The images were reviewed separately by two radiologists and two nuclear medicine physicians, who were blinded to the results of another imaging modality. Results: A total of 169 metastatic lesions in 69 regions of 30 patients were detected by whole body MR DWI while 156 lesions in 68 regions of 29 patients were identified by skeletal scintigraphy. There were two cases negative in scintigraphy but positive in whole body MR DWI and one case positive in scintigraphy only. There were eight lesions negative in scintigraphy but positive in whole body MR DWI, mainly located in the spine, pelvis and femur. Seven lesions were only detected by scintigraphy, mainly located in the skull, sternum, clavicle and scapula. Conclusion: The whole body MR DWI reveals excellent consistency with skeletal scintigraphy regarding bone metastasis, and the two modalities are complementary for each other. (authors)

  3. The significance of diffusion weighted imaging for the diagnosis of pyogenic ventriculitis

    Energy Technology Data Exchange (ETDEWEB)

    Ihn, Yon Kwon; Hwang, Seong Su [College of Medicine, The Catholic University of Korea, Suwon (Korea, Republic of); Kim, Tae You [Willis Hospital, Seoul (Korea, Republic of)

    2007-08-15

    To evaluate the significance of diffusion weighted imaging (DWI) for the diagnosis of pyogenic ventriculitis. In this retrospective study, 9 patients with pyogenic ventricultis underwent a set of imaging sequences that included DWI, T1-and T2-weighted imaging. FLAIR and enhanced T1 weighted imaging. DWI consisted of an axial single shot spine echo EPI pulse sequence with b values of 0 and 1000 sec/mm{sup 2}. We evaluated the presence and signal intensity of ventricular debris, hydrocephalus, periventricular signal abnormality, and ependymal enhancement. The apparent diffusion coffiecient values of ventricular debris and cortical gray matter were calculated from the ADC map. In all patients, ventricular debris was hyperintense on the DWIs. A periventricular hyperintense signal was present in all cases on FLAIR and T2WI. Ependymal enhancement was detected in eight (89%) of 9 cases. A hydrocephalus was observed in 6 (67%) of 9 cases. The mean ADC value of ventricular debris was 0.735 {+-} 0.117 (10{sup -3} mm{sup 2}/sec). These ADC values were significantly lower than those for cortical gray matter (1.052 {+-} 0.149 (10{sup -3} mm{sup 2}/sec)). Ventricular debris was most conspicuous findings of ventriculitis on DWI. Areas of intraventricular hyperintensity on DWI corresponded to the decreased ADC values.

  4. Clinical value of diffusion-weighted MR imaging in acute contusion of spinal cord

    International Nuclear Information System (INIS)

    Zhang Jinsong; Huan Yi; Sun Lijun; Zhao Haitao; Ge Yali; Chang Yingjuan; Yang Chunmin

    2005-01-01

    Objective: To study the clinical value of diffusion-weighted MR imaging (DWI) in acute contusion of spinal cord. Methods: Eighteen cases with acute contusion of spinal cord were examined with routine MRI and DWI, including single-shot DWI (ssh-DWI) in 2 cases and multi-shot DWI (msh-DWI) in 16 cases, on a 1.5-tesla MR system within 72 h post-trauma. Results: Two cases examined by ssh-DWI showed local lesions with significant high signals, but ssh-DWI images could not be used to measure apparent diffusion coefficient (ADC) value due to its weak resolution. Other 16 cases examined by msh-DWI showed better images and were classified into three categories depending on different degrees of tissue injury and characteristics of DWI: (1) Edema-type: ten cases presented DWI high signals with different degree in local lesions. There were significant difference of ADC values between lesions and normal parts (t=7.515, P 2 WI heterogeneous high signals and T 1 WI low signals due to prominent hemorrhage. Conclusion: DWI of the spinal cord provided satisfactory images and was a useful method for visualizing the injury cord in the super-early stage, helping determine integrity and compression degree of spinal cord and detecting hemorrhage. (authors)

  5. Diffusion-weighted imaging of brain metastases: their potential to be misinterpreted as focal ischaemic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Geijer, B. [Department of Radiology, University Hospital, Lund (Sweden); Holtaas, S. [Department of Diagnostic Imaging, King Fahd Hospital, Riyadh (Saudi Arabia)

    2002-07-01

    Small focal ischaemic brain lesions are said to be easy to identify in the acute stage and to differentiate from older lesions using diffusion-weighted imaging (DWI). Brain metastases are common and the aim of this study was to evaluate the risk of misinterpretation as ischaemic lesions in a standard MRI protocol for clinical stroke. Of 26 patients investigated with MRI for possible metastases, 12 did have metastatic brain lesions, including most of the common tumours. On a 1.5 tesla imager, we obtained DWI, plus T2- and T1-weighted images, the latter before and after triple-dose contrast medium. Well-circumscribed brain lesions with a decreased apparent diffusion coefficient and a slightly or moderately increased signal on T2-weighted images were found in patients with metastases from a small-cell bronchial carcinoma and a pulmonary adenocarcinoma. The same features were also found in metastases from a breast carcinoma but the lesions were surrounded by oedema. With a standard DWI protocol, the features of common brain metastases may overlap with those of small acute and subacute ischaemic lesions. (orig.)

  6. IgG4-related kidney disease: MRI findings with emphasis on the usefulness of diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bohyun; Kim, Jin Hee, E-mail: kimjhrad@amc.seoul.kr; Byun, Jae Ho; Kim, Hyoung Jung; Lee, Seung Soo; Kim, So Yeon; Lee, Moon-Gyu

    2014-07-15

    Objectives: To investigate the imaging findings of immunoglobulin G4 (IgG4)-related kidney disease (IgG4-KD) on magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) and to evaluate the usefulness of DWI in lesion detection. Methods: This retrospective cohort study included 31 patients with IgG4-KD who underwent MRI covering both kidneys. Two radiologists reviewed in consensus the MR images to determine the distribution pattern (location, laterality, and multiplicity) and the visually assessed signal intensity (hypointense, isointense or hyperintense) of the renal lesions compared to the normal renal parenchyma on each sequence. Per-patient sensitivity for detecting IgG4-KD and the number of detectable lesions were compared in T2-weighted images, DWI, and dynamic contrast-enhanced images. Results: IgG4-KD typically manifested as bilateral (83.9%), multiple (93.5%), and renal parenchymal (87.1%) nodules appearing isointense (93.5%) on T1-weighted images, hypointense (77.4%) on T2-weighted images, hyperintense (100%) on DWI (b = 1000), and hypointense (83.3%) in the arterial phase and with a progressive enhancement pattern on dynamic contrast-enhanced images. The sensitivity of DWI for detecting IgG4-KD was significantly higher than that of T2-weighted images (100% vs. 77.4%, P = 0.034). The median number of detectable lesions was significantly greater in DWI (n = 9) than in T2-weighted images (n = 2) and dynamic contrast-enhanced images (n = 5) (P ≤ 0.008). Conclusions: The characteristic MRI findings of IgG4-KD were bilateral, multiple, renal parenchymal nodules with T2 hypointensity, diffusion restriction, and a progressive enhancement pattern. As DWI was useful in the detection of IgG4-KD, adding DWI to conventional MRI for patients suspected of having IgG4-KD may enhance the diagnosis.

  7. IgG4-related kidney disease: MRI findings with emphasis on the usefulness of diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Kim, Bohyun; Kim, Jin Hee; Byun, Jae Ho; Kim, Hyoung Jung; Lee, Seung Soo; Kim, So Yeon; Lee, Moon-Gyu

    2014-01-01

    Objectives: To investigate the imaging findings of immunoglobulin G4 (IgG4)-related kidney disease (IgG4-KD) on magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) and to evaluate the usefulness of DWI in lesion detection. Methods: This retrospective cohort study included 31 patients with IgG4-KD who underwent MRI covering both kidneys. Two radiologists reviewed in consensus the MR images to determine the distribution pattern (location, laterality, and multiplicity) and the visually assessed signal intensity (hypointense, isointense or hyperintense) of the renal lesions compared to the normal renal parenchyma on each sequence. Per-patient sensitivity for detecting IgG4-KD and the number of detectable lesions were compared in T2-weighted images, DWI, and dynamic contrast-enhanced images. Results: IgG4-KD typically manifested as bilateral (83.9%), multiple (93.5%), and renal parenchymal (87.1%) nodules appearing isointense (93.5%) on T1-weighted images, hypointense (77.4%) on T2-weighted images, hyperintense (100%) on DWI (b = 1000), and hypointense (83.3%) in the arterial phase and with a progressive enhancement pattern on dynamic contrast-enhanced images. The sensitivity of DWI for detecting IgG4-KD was significantly higher than that of T2-weighted images (100% vs. 77.4%, P = 0.034). The median number of detectable lesions was significantly greater in DWI (n = 9) than in T2-weighted images (n = 2) and dynamic contrast-enhanced images (n = 5) (P ≤ 0.008). Conclusions: The characteristic MRI findings of IgG4-KD were bilateral, multiple, renal parenchymal nodules with T2 hypointensity, diffusion restriction, and a progressive enhancement pattern. As DWI was useful in the detection of IgG4-KD, adding DWI to conventional MRI for patients suspected of having IgG4-KD may enhance the diagnosis

  8. Analysis of longitudinal diffusion-weighted images in healthy and pathological aging: An ADNI study.

    Science.gov (United States)

    Kruggel, Frithjof; Masaki, Fumitaro; Solodkin, Ana

    2017-02-15

    The widely used framework of voxel-based morphometry for analyzing neuroimages is extended here to model longitudinal imaging data by exchanging the linear model with a linear mixed-effects model. The new approach is employed for analyzing a large longitudinal sample of 756 diffusion-weighted images acquired in 177 subjects of the Alzheimer's Disease Neuroimaging initiative (ADNI). While sample- and group-level results from both approaches are equivalent, the mixed-effect model yields information at the single subject level. Interestingly, the neurobiological relevance of the relevant parameter at the individual level describes specific differences associated with aging. In addition, our approach highlights white matter areas that reliably discriminate between patients with Alzheimer's disease and healthy controls with a predictive power of 0.99 and include the hippocampal alveus, the para-hippocampal white matter, the white matter of the posterior cingulate, and optic tracts. In this context, notably the classifier includes a sub-population of patients with minimal cognitive impairment into the pathological domain. Our classifier offers promising features for an accessible biomarker that predicts the risk of conversion to Alzheimer's disease. Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found at: http://adni.loni.usc.edu/wp-content/uploads/how to apply/ADNI Acknowledgement List.pdf. Significance statement This study assesses neuro-degenerative processes in the brain's white matter as revealed by diffusion-weighted imaging, in order to discriminate healthy from pathological aging in a large sample of elderly subjects. The analysis of time

  9. The experimental study on liver VX-2 tumor by using MR diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Yuan Youhong; Xiao Enhua; Jin Ke; Yan Ronghua; He Zhong; Shang Quanliang; Hu Weizhou; Yuan Shiwen; Xiang Jun; Tang Keli; Yi Shijian; Yin Qiang

    2005-01-01

    Objective: To study the imaging characteristics of rabbit's liver VX-2 tumor on MR diffusion-weighted imaging. Methods: Of the 35 New Zealand rabbits, 14 were implanted under the skin while 6 were implanted in liver with VX-2 tumor in preparing experiment, and 12 were implanted in liver and 3 as controls in formal experiment. Before and after the implantation, MR diffusion-weighted imaging (DWI), T 1 -weighted and T 2 -weighted images were performed respectively and periodically in 15 tumors including 12 liver tumor implantations in formal experiment. DWI parameters including apparent diffusion coefficient (ADC) value were acquired and statistically analyzed by SPSS 10.0. Results: (1) The successful rate of implantation was 29% (4/14) under the skin and 33% (2/6) in the liver in preparing experiment. And the successful rate of formal experiment was 83% (10/12). (2) DWI signal of VX-2 tumor was high and the signal became lower and lower with b value increased step by step. The signal of VX-2 tumor on ADC map was low. The ADC value of normal group was (2.57 ± 0.26) mm 2 /s (b=100 s/mm 2 ) and (1.73 ± 0.31) mm 2 /s (b=300 s/mm 2 ), and ADC value of VX-2 tumor group was (1.87 ± 0.25) mm 2 /s (b=100 s/mm 2 ) and (1.57 ± 0.23) mm 2 /s (b=300 s/mm 2 ), respectively.The F value of analysis of variance was 43.26 (P<0.001). The distinction of tumor ADC value in different b values was significant (P<0.05), and the distinction of ADC value between VX-2 tumor and normal liver was also significant (P<0.01). (3) VX-2 tumor developed quickly and metastasized early to all parts of the body, especially to the lung, the liver, the lymph nodes of mediastinum and so on. Conclusion: DWI signal of VX-2 tumor has its characteristic and DWI has important value in reflecting the movement of water molecules, discovering the VX-2 tumor, and tracking its progress. (authors)

  10. Diffusion-weighted imaging-guided MR spectroscopy in breast lesions using readout-segmented echo-planar imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Kun; Chai, Weimin; Zhan, Ying; Luo, Xianfu; Yan, Fuhua [Shanghai Jiao Tong University School of Medicine, Department of Radiology, Ruijin Hospital, Shanghai (China); Fu, Caixia [Siemens MRI Center, Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen (China); Shen, Kunwei [Shanghai Jiao Tong University School of Medicine, Comprehensive Breast Health Center, Ruijin Hospital, Shanghai (China)

    2016-06-15

    To investigate the feasibility and effectiveness of diffusion-weighted imaging (DWI)-guided magnetic resonance spectroscopy (MRS) using readout-segmented echo-planar imaging (RS-EPI) to characterise breast lesions. A total of 258 patients with 258 suspicious breast lesions larger than 1 cm in diameter were examined using DWI-guided, single-voxel MRS with RS-EPI. The mean total choline-containing compound (tCho) signal-to-noise ratio (SNR) and concentration were used for the interpretation of MRS data. T-tests, χ{sup 2}-tests, receiver operating characteristic (ROC) curve analyses and Pearson correlations were conducted for statistical analysis. Histologically, 183 lesions were malignant, and 75 lesions were benign. Both the mean tCho SNR and concentration of malignant lesions were higher than those of benign lesions (6.23 ± 3.30 AU/mL vs. 1.26 ± 1.75 AU/mL and 3.17 ± 2.03 mmol/kg vs. 0.86 ± 0.83 mmol/kg, respectively; P < 0.0001). For a tCho SNR of 2.0 AU/mL and a concentration of 1.76 mmol/kg, the corresponding areas under the ROC curves were 0.93 and 0.90, respectively. The mean tCho SNR and concentration negatively correlated with apparent diffusion coefficients calculated from RS-EPI, with correlation coefficients of -0.54 and -0.48, respectively. DWI-guided MRS using RS-EPI is feasible and accurate for characterising breast lesions. (orig.)

  11. Sequential MR imaging (with diffusion-weighted imaging changes in metronidazole-induced encephalopathy

    Directory of Open Access Journals (Sweden)

    Rupinder Singh

    2017-01-01

    Full Text Available Metronidazole-induced neuro-toxicity, though rare, is known. A characteristic spatial distribution of lesions in cerebellar dentate nuclei and dorsal pons is known. However, temporal progression of lesions on magnetic resonance imaging (MRI has not been described previously. We describe two such cases which presented initially with splenial hyperintesity and showed progression to characterstic lesions. Both cases improved with stoppage of metronidazole.

  12. Ischemic lesion volume determination on diffusion weighted images vs. apparent diffusion coefficient maps.

    Science.gov (United States)

    Bråtane, Bernt Tore; Bastan, Birgul; Fisher, Marc; Bouley, James; Henninger, Nils

    2009-07-07

    Though diffusion weighted imaging (DWI) is frequently used for identifying the ischemic lesion in focal cerebral ischemia, the understanding of spatiotemporal evolution patterns observed with different analysis methods remains imprecise. DWI and calculated apparent diffusion coefficient (ADC) maps were serially obtained in rat stroke models (MCAO): permanent, 90 min, and 180 min temporary MCAO. Lesion volumes were analyzed in a blinded and randomized manner by 2 investigators using (i) a previously validated ADC threshold, (ii) visual determination of hypointense regions on ADC maps, and (iii) visual determination of hyperintense regions on DWI. Lesion volumes were correlated with 24 hour 2,3,5-triphenyltetrazoliumchloride (TTC)-derived infarct volumes. TTC-derived infarct volumes were not significantly different from the ADC and DWI-derived lesion volumes at the last imaging time points except for significantly smaller DWI lesions in the pMCAO model (p=0.02). Volumetric calculation based on TTC-derived infarct also correlated significantly stronger to volumetric calculation based on last imaging time point derived lesions on ADC maps than DWI (pdetermined lesion volumes on ADC maps and DWI by both investigators correlated significantly with threshold-derived lesion volumes on ADC maps with the former method demonstrating a stronger correlation. There was also a better interrater agreement for ADC map analysis than for DWI analysis. Ischemic lesion determination by ADC was more accurate in final infarct prediction, rater independent, and provided exclusive information on ischemic lesion reversibility.

  13. The preliminary study of MR diffusion weighted imaging with background body signal suppression on pulmonary diseases

    International Nuclear Information System (INIS)

    Wu Huawei; Cheng Jiejun; Xu Jianrong; Lu Qing; Ge Xin; Li Lei

    2008-01-01

    Objective: To evaluate maximum intensity projection (MIP) images and apparent diffusion coefficient (ADC) values of MR diffusion weighted imaging with background body signal suppression (DWIBS) on pulmonary diseases. Methods: Sixty-one patients with pulmonary diseases underwent DWlBS. The findings in three dimensional(3D) MIP image were observed and the ADC values of diseased region were measured. The diagnostic value of DWIBS on pulmonary diseases was evaluated. Results: Lung cancer and inflammatory disease were all demonstrated as dense intensity area on DWIBS. The mean ADC value of central lung cancer was (1.05±0.23) x 10 -3 mm 2 /s. The mean ADC value of peripheral lung cancer was (1.10 ± 0.17) x 10 -3 mm 2 /s. The mean ADC value of the inflammatory disease was (1.69 ± 0.29) x 10 -3 mm 2 /s. The mean ADC value had significant difference between peripheral lung cancer and the inflammatory disease (P<0.05). The MR sensitivity, specificity and accuracy in diagnosing the pulmonary diseases with DWIBS (86.84%, 82.60%, 85.24%, respectively) was higher than conventional MRI(78.94%, 78.26%, and 78.68%, respectively). Conclusion: DWIBS can demonstrate clearly the lesion's shape with 3D display. The quantitative measurement of ADC values is feasible. DWIBS may be a potential diagnostic method for differentiation on pulmonary diseases. (authors)

  14. Diffusion-weighted imaging of breast tumours at 3 Tesla and 7 Tesla: a comparison

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, S.; Minarikova, L.; Zaric, O.; Chmelik, M.; Strasser, B.; Trattnig, S.; Bogner, W. [Medical University Vienna, MRCE, Department of Biomedical imaging and Image-Guided Therapy, Vienna (Austria); Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna (Austria); Pinker, K.; Baltzer, P.; Helbich, T. [Medical University Vienna, Division of Molecular and Gender Imaging, Department of Biomedical imaging and Image-Guided Therapy, Vienna (Austria)

    2016-05-15

    To compare bilateral diffusion-weighted MR imaging (DWI) at 3 T and 7 T in the same breast tumour patients. Twenty-eight patients were included in this IRB-approved study (mean age 56 ± 16 years). Before contrast-enhanced imaging, bilateral DWI with b = 0 and 850 s/mm{sup 2} was performed in 2:56 min (3 T) and 3:48 min (7 T), using readout-segmented echo planar imaging (rs-EPI) with a 1.4 x 1.4 mm{sup 2} (3 T)/0.9 x 0.9 mm{sup 2} (7 T) in-plane resolution. Apparent diffusion coefficients (ADC), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were assessed. Twenty-eight lesions were detected (18 malignant, 10 benign). CNR and SNR were comparable at both field strengths (p > 0.3). Mean ADC values at 7 T were 4-22 % lower than at 3 T (p ≤ 0.03). An ADC threshold of 1.275 x 10{sup -3} mm{sup 2}/s resulted in a diagnostic specificity of 90 % at both field strengths. The sensitivity was 94 % and 100 % at 3 T and 7 T, respectively. 7-T DWI of the breast can be performed with 2.4-fold higher spatial resolution than 3 T, without significant differences in SNR if compared to 3 T. (orig.)

  15. Visualization of white matter tracts using a non-diffusion weighted magnetic resonance imaging method: does intravenous gadolinium injection four hours prior to the examination affect the visualization of white matter tracts?

    Directory of Open Access Journals (Sweden)

    Masahiro Yamazaki

    Full Text Available OBJECTIVES: Visualization of white matter (WM-tracts such as the corticospinal tract (CST, medial lemniscus (ML, and superior cerebellar peduncle (SCP using delayed enhanced (DE-heavily T2-weighted three-dimensional fluid-attenuated inversion-recovery (hT2w-3D-FLAIR imaging has recently been reported. In that report, all patients were clinically suspected of having Ménière's disease, because DE-hT2w-3D-FLAIR imaging of the inner ear has been reported to separately visualize perilymph and endolymph fluid and can identify the presence of endolymphatic hydrops. Therefore, the previous report could not rule out the possible effect of delayed enhancement. From this perspective, the purpose of this study was to elucidate if the use of gadolinium affects the visualization of WM-tracts on hT2w-3D-FLAIR. MATERIALS AND METHODS: The records of nine patients with suspected Ménière's disease who underwent plain (P and DE-hT2w-3D-FLAIR by 3-Tesla were retrospectively analyzed. The regions of interest were set on the CST, ML, and SCP, and on contiguous brain parenchyma: The thalamus (Th, pontine parenchyma (PP, and cerebellar parenchyma (CP, respectively. The signal intensity ratio between each WM-tract and the relevant contiguous brain parenchyma was calculated for both P- and DE-hT2w-3D-FLAIR images, and statistically compared using paired t-tests. RESULTS: The CST/Th signal intensity ratio was 3.75±0.67 on P-hT2w-3D-FLAIR and 3.62±0.50 on DE-hT2w-3D-FLAIR (p = 0.24. The ML/PP signal intensity ratio was 2.19±0.59 on P-hT2w-3D-FLAIR and 2.08±0.53 on DE-hT2w-3D-FLAIR (p = 0.25. The SCP/CP signal intensity ratio was 4.08±0.91 on P-hT2w-3D-FLAIR and 4.04±0.96 on DE-hT2w-3D-FLAIR (p = 0.43. There were no significant differences in the signal intensity ratios between P- and DE-hT2w-3D-FLAIR images. CONCLUSIONS: The use of gadolinium is not necessary for visualization of WM-tracts using hT2w-3D-FLAIR, and P-hT2w-3D-FLAIR without gadolinium may

  16. Gastrointestinal stromal tumours: Correlation of modified NIH risk stratification with diffusion-weighted MR imaging as an imaging biomarker

    International Nuclear Information System (INIS)

    Kang, Tae Wook; Kim, Seong Hyun; Jang, Kyung Mi; Choi, Dongil; Ha, Sang Yun; Kim, Kyoung-Mee; Kang, Won Ki; Kim, Min Ji

    2015-01-01

    Highlights: • Except size and necrosis, conventional MR findings of GISTs were not significantly different according to the modified NIH criteria. • The ADC values of GISTs were negatively correlated with the modified NIH criteria. • The ADC value can be helpful for the determination of intermediate or high-risk GISTs. - Abstract: Purpose: To evaluate the correlation of risk grade of gastrointestinal stromal tumours (GISTs) based on modified National Institutes of Health (NIH) criteria with conventional magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging. Methods: We included 22 patients with histopathologically proven GISTs in the stomach or small bowel who underwent pre-operative gadoxetic acid-enhanced MR imaging and DW imaging. We retrospectively assessed correlations between morphologic findings, qualitative (signal intensity, consensus from two observers) and quantitative (degree of dynamic enhancement using signal intensity of tumour/muscle ratio and apparent diffusion coefficient [ADC]) values, and the modified NIH criteria for risk stratification. Spearman partial correlation analysis was used to control for tumour size as a confounding factor. The optimal cut-off level of ADC values for intermediate or high risk GISTs was analyzed using a receiver operating characteristic analysis. Results: Except tumour size and necrosis, conventional MR imaging findings, including the degree of dynamic enhancement, were not significantly different according to the modified NIH criteria (p > 0.05). Tumour ADC values were negatively correlated with the modified NIH criteria, before and after adjustment of tumour size (ρ = −0.754; p < 0.001 and ρ = −0.513; p = 0.017, respectively). The optimal cut-off value for the determination of intermediate or high-risk GISTs was 1.279 × 10 −3 mm 2 /s (100% sensitivity, 69.2% specificity, 81.8% accuracy). Conclusion: Except tumour size and necrosis, conventional MR imaging findings did not correlate with

  17. Gastrointestinal stromal tumours: Correlation of modified NIH risk stratification with diffusion-weighted MR imaging as an imaging biomarker

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Tae Wook [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Kim, Seong Hyun, E-mail: kshyun@skku.edu [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Jang, Kyung Mi; Choi, Dongil [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Ha, Sang Yun; Kim, Kyoung-Mee [Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Kang, Won Ki [Division of Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Kim, Min Ji [Biostatics Unit, Samsung Biomedical Research Institute, Samsung Medical Center, Seoul 135-710 (Korea, Republic of)

    2015-01-15

    Highlights: • Except size and necrosis, conventional MR findings of GISTs were not significantly different according to the modified NIH criteria. • The ADC values of GISTs were negatively correlated with the modified NIH criteria. • The ADC value can be helpful for the determination of intermediate or high-risk GISTs. - Abstract: Purpose: To evaluate the correlation of risk grade of gastrointestinal stromal tumours (GISTs) based on modified National Institutes of Health (NIH) criteria with conventional magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging. Methods: We included 22 patients with histopathologically proven GISTs in the stomach or small bowel who underwent pre-operative gadoxetic acid-enhanced MR imaging and DW imaging. We retrospectively assessed correlations between morphologic findings, qualitative (signal intensity, consensus from two observers) and quantitative (degree of dynamic enhancement using signal intensity of tumour/muscle ratio and apparent diffusion coefficient [ADC]) values, and the modified NIH criteria for risk stratification. Spearman partial correlation analysis was used to control for tumour size as a confounding factor. The optimal cut-off level of ADC values for intermediate or high risk GISTs was analyzed using a receiver operating characteristic analysis. Results: Except tumour size and necrosis, conventional MR imaging findings, including the degree of dynamic enhancement, were not significantly different according to the modified NIH criteria (p > 0.05). Tumour ADC values were negatively correlated with the modified NIH criteria, before and after adjustment of tumour size (ρ = −0.754; p < 0.001 and ρ = −0.513; p = 0.017, respectively). The optimal cut-off value for the determination of intermediate or high-risk GISTs was 1.279 × 10{sup −3} mm{sup 2}/s (100% sensitivity, 69.2% specificity, 81.8% accuracy). Conclusion: Except tumour size and necrosis, conventional MR imaging findings did not

  18. High b-value diffusion-weighted MR imaging of normal brain at 3 T

    International Nuclear Information System (INIS)

    Cihangiroglu, Mutlu; Ulug, Aziz Muefit; Firat, Zeynep; Bayram, Ali; Kovanlikaya, Arzu; Kovanlikaya, Ilhami

    2009-01-01

    Introduction: The purpose of this study was to determine the normative apparent diffusion coefficient (ADC) values at 3 T using high b-value (3000 s/mm 2 ) diffusion-weighted images (DWI) and compare the signal characteristics of the high b value with standard b-value (1000 s/mm 2 ) DWI. Methods: Institutional review board approval was obtained for this prospective study which included 20 volunteers (10 M, 10 F, mean age: 38.7 ± 14.9) without any known clinical disease or radiological findings. All brain examinations were performed with 3 T MR by using similar parameters of b1000 and b3000 DWI sequences. DWI and ADC maps were obtained. Signal intensity, noise, signal to noise ratio (SNR), contrast to noise (CNR), contrast ratio (CR), and ADC values of bilateral posterior limb of internal capsule, frontal white matter, parietal gray matter, pons, thalamus, splenium of corpus callosum were measured on b1000 and b3000 DW images. Results: In all anatomic locations, MR signal intensity, SNR and ADC values of b3000 images were significantly lower than MR signal intensity, SNR and ADC values of b1000 images (p < 0.001). The CNR and CR values at the posterior limb of internal capsule and pons were significantly increased on b3000 images (p < 0.001) and decreased in the other regions measured. Conclusion: The ADC values calculated from standard b-value DWI were significantly higher than those calculated from high b-value DWI. These results agree with the previous studies. In the regions where CNR values increase with high b value, b3000 DWI images may provide additional clinical information.

  19. Assessment of patency capsule retention using MR diffusion-weighted imaging

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    Klang, Eyal; Rozendorn, Noa; Amitai, Michal Marianne [Sheba Medical Center, Department of Diagnostic Imaging, Ramat Gan (Israel); Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Kopylov, Uri; Ben-Horin, Shomron; Lahat, Adi; Yablecovitch, Doron; Eliakim, Rami [Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Sheba Medical Center, Department of Gastroenterology, Ramat Gan (Israel)

    2017-12-15

    Evaluate the ability of MR diffusion-weighted imaging (DWI) to predict patency capsule retention in Crohn's disease (CD). Clinical and imaging data were prospectively reviewed for 80 CD patients following patency capsule administration and MR-DWI under institutional review board (IRB) approval with informed consent. Two radiologists separately assessed the presence/absence of restricted diffusion in the distal ileum. Apparent diffusion coefficients (ADC) from three regions of interest on the ileal wall were averaged. The association between restricted diffusion and retention, and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. Ability of ADC to predict retention was assessed with receiver operating characteristic (ROC) curve analysis. Restricted diffusion in the distal ileum was associated with capsule retention (p = 0.001, p < 0.0001). Sensitivity, specificity, PPV and NPV of restricted diffusion for capsule retention were 100.0%, 46.2%, 30.0%, 100% and 100.0%, 56.9%, 34.9%, 100%, respectively, for two radiologists. Accuracy of ADC to predict retention was high (area under the curve = 0.851, p < 0.0001). An ADC of 1.47 mm{sup 2}/s showed 90.0% sensitivity and 50.0% specificity for retention. Sensitivity and NPV of restricted diffusion for patency capsule retention were 100%, suggesting that DWI may predict gastrointestinal tract capability to pass video camera endoscopy. (orig.)

  20. Comparisons of carotid artery stenting and carotid endoarterectomy in terms of diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Mitsuoka, Hiroshi; Shintani, Tsunehiro; Masuda, Mikio; Higashi, Shigeki

    2009-01-01

    The objective of this study was to compare two methods of treatment for carotid arterial stenosis, carotid endarterectomy (CEA) and carotid artery stenting (CAS), by means of diffusion-weighted MR imaging (DWI). Nineteen treatments in 18 cases during the 2007 academic year were included in this study. CAS was performed for 9 cases with 10 lesions (10 procedures), while 9 cases with 9 lesions (9 procedures) were treated by CEA. Patients were examined by a neurologist before and after the procedure, and had pre- and post-procedural DWI. No strokes or transient ischemic attacks (TIAs) were observed in these cases. New DWI lesions were found in 7 out of the 10 procedures of CAS imaged 24 hours postprocedure, (average: 2.0 lesions). No new lesions were detected on DWI of CEA cases (χ 2 =8.33, p=0.0039). Certain high-risk subsets may respond well to CAS with a very low incidence of clinically-evident neurologic events, but with significantly higher incidence of periprocedural micro-brain embolism. Currently, CEA should be the first choice of treatment for atherosclerotic carotid artery stenosis. (author)

  1. Diagnostic value of MR diffusion weighted imaging in prostate cancer of central glands

    International Nuclear Information System (INIS)

    Xiao Lihua; Zheng Xiaolin; He Qiang; Luo Daosheng; Zhang Kunlin; Zou Yujian

    2010-01-01

    Objective: To discuss the diagnostic value of diffusion weighted imaging (DWI) in prostate cancer of central glands (CGPca) and differentiate from benign hyperlasia (BHP). Methods: All patients included 15 cases of prostate cancer of central glands and 20 cases of benign prostatic hyperplasia. DWI were obtained with factor b of 800 s/mm 2 . DWI and ADC map appearances were reviewed in all patients. ADC values of CGPca and PBH tissues were measured and analysed statistically. Results: All of 15 CGPca cases showed markedly markedly high-signal on DWI and low-signal on ADC map, both could clearly demonstrate the area of CGPca. But 6 cases were misdiagnosed as PBH by conventional imaging because of the tumors limited to central glands. The mean ADG values of CGPca cases and BPH cases were (0.93±0.13) x 10 -3 mm 2 /s and (11.53±0.12) x 10 -3 mm 2 /s respectively. There were significant differences in CGPca and BPH. Conclusion: It has an important clinical value in diagnosing prostate cancer of central glands and differentiating from BHP with DWI and ADC values. (authors)

  2. False-negative diffusion-weighted imaging findings in acute stroke

    International Nuclear Information System (INIS)

    Ishikawa, Tatsuya; Yuasa, Naoki; Otomo, Takashi; Shiramizu, Hideki; Matsuda, Hiroshi; Kitagawa, Yasuhisa; Takagi, Shigeharu

    2006-01-01

    The utility of DWI (diffusion-weighted imaging) has been established in acute ischemic stroke. However, some patients with acute stroke show no abnormal signals on DWI, despite the presence of infarction (false-negative DWI). We analyzed the relationship between false-negative DWI and the clinical manifestations of acute ischemic stroke in 151 DWI-positive (89%) and 19 false-negative DWI (11%) patients. We performed MRI within 24 hours after onset at our hospital. Non-specific clinical manifestations, including vertigo and nausea, were frequently observed in false-negative DWI patients. As regards the vascular territory, false-negative DWI was noted in 15.3% of 59 patients with infarctions within the territory of the vertebrobasilar artery. Concerning the duration from onset to initial imaging, 73.7% of the patients with false-negative DWI findings underwent MRI examination within 6 hours after onset. Of the patients with false-negative DWI, 84.2% had lacunar infarction (χ 2 =16.4, P<0.001). In conclusion, false negative DWI is more frequently observed in lacunar infarction than in atherothrombotic infarction or cardiogenic embolism. It is important to examine carefully the neurological changes occurring in patients who present with acute stroke, but have negative DWI findings. (author)

  3. Value of diffusion-weighted MR imaging in the diagnosis of Creutzfeldt-Jakob disease

    International Nuclear Information System (INIS)

    Xu Quangang; Wu Weiping; Huang Dehui; Zhang Jiatang; Lang Senyang; Pu Chuanqiang

    2005-01-01

    Objective: To assess the diagnosis value of diffusion- weighted imaging (DWI) in Creutzfeldt-Jakob disease (CJD). Methods: 8 cases of sporadic CJD who underwent MRI were reported. 4 cases were definite, 3 cases were probable and 1 case was possible. The sensitivity of DWI and conventional MRI were compared. Results: T 1 WI and T 2 WI revealed no abnormal signals except nonspecific diffuse brain atrophy in 4 cases, whereas DWI detected hyperintense abnormalities in all cases. 2 cases showed linear lesions only in the cerebral cortex, and 6 cases showed lesions in both the cerebral cortex and the striatum. The lesions were symmetric in 5 cases, but were asymmetric in the other 3 cases. Although fluid- attenuated inversion recovery (FLAIR) imaging also showed cortical hyperintensity in 1 case, the high signal changes were more evident and extensive on DWI. Conclusions: The hyperintense changes in the cerebral cortices and/or striata on DWI are considered characteristic of CJD. DWI is more sensitive than conventional MRI in depicting lesions of CJD and may be an essential tool for the early diagnosis of this disease. (authors)

  4. Assessment of patency capsule retention using MR diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Klang, Eyal; Rozendorn, Noa; Amitai, Michal Marianne; Kopylov, Uri; Ben-Horin, Shomron; Lahat, Adi; Yablecovitch, Doron; Eliakim, Rami

    2017-01-01

    Evaluate the ability of MR diffusion-weighted imaging (DWI) to predict patency capsule retention in Crohn's disease (CD). Clinical and imaging data were prospectively reviewed for 80 CD patients following patency capsule administration and MR-DWI under institutional review board (IRB) approval with informed consent. Two radiologists separately assessed the presence/absence of restricted diffusion in the distal ileum. Apparent diffusion coefficients (ADC) from three regions of interest on the ileal wall were averaged. The association between restricted diffusion and retention, and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. Ability of ADC to predict retention was assessed with receiver operating characteristic (ROC) curve analysis. Restricted diffusion in the distal ileum was associated with capsule retention (p = 0.001, p < 0.0001). Sensitivity, specificity, PPV and NPV of restricted diffusion for capsule retention were 100.0%, 46.2%, 30.0%, 100% and 100.0%, 56.9%, 34.9%, 100%, respectively, for two radiologists. Accuracy of ADC to predict retention was high (area under the curve = 0.851, p < 0.0001). An ADC of 1.47 mm 2 /s showed 90.0% sensitivity and 50.0% specificity for retention. Sensitivity and NPV of restricted diffusion for patency capsule retention were 100%, suggesting that DWI may predict gastrointestinal tract capability to pass video camera endoscopy. (orig.)

  5. MR diffusion weighted imaging experimental study on early stages of articular cartilage degeneration of knee

    International Nuclear Information System (INIS)

    Dai Jingru; Dai Shipeng; Pang Jun; Xu Xiaokun; Wang Yuexin; Zhang Zhigang

    2008-01-01

    Objective: To study the appearance of MR diffusion weighted imaging in early stages of cartilage degeneration and to detect its values. Methods: In 20 goat left knees, intra- articular injection of 5 units of papain was performed causing a loss of cartilage proteoglycan. Twenty right knees were used as control group. MR diffusion weighted imaging was performed at 24 hours after intra-articular injection of papain. ADC of each part of articular cartilage was measured and compared with each other. The proteoglycan content was measured biochemically and histochemically. Routine MRI and DWI were performed in 100 patients with osteoarthritis and 20 healthy people. The ADC of each interested part of articular cartilage was measured and compared with each other. Results: In experimental control group, the ADCav of articular cartilage was (14.2±2.3) x 10 -4 mm 2 /s. In early stages of cartilage degeneration group, the ADCav of articular cartilage was (17.5±4.2) x 10 -4 mm 2 /s. The ADCav of the control group was lower than that of the early stages of cartilage degeneration group (t=2.709; P=0.016). The proteloglycan content of articular cartilage was 4.22 x 10 6 μg/kg in control group, and 0.82 x 10 6 μg/kg in experimental group at 24 hours after injection of papain. The difference between control group and experimental group was significant (t=2.705, P=0.018). In healthy people, the ADCav of articular cartilage was (7.6±2.2) x 10 -4 mm 2 /s. In osteoarthritis group, the ADCav of articular cartilage was (10.3±4.2) x 10 -4 mm 2 /s. The ADCav in the healthy group was significantly lower than that in the osteoarthritis group (t=2.609,P=0.014). Conclusion: DWI is an useful method in detecting early stages of cartilage degeneration which can not be showed on routine sequences. (authors)

  6. Readout-segmented echo-planar imaging improves the image quality of diffusion-weighted MR imaging in rectal cancer: Comparison with single-shot echo-planar diffusion-weighted sequences

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    Xia, Chun-chao; Liu, Xi; Peng, Wan-lin; Li, Lei; Zhang, Jin-ge [Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Meng, Wen-jian; Deng, Xiang-bing [Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041 (China); Zuo, Pan-li [Siemens Healthcare, MR Collaborations NE Asia, 100010, Beijing (China); Li, Zhen-lin, E-mail: lzlcd01@126.com [Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, Sichuan 610041 (China)

    2016-10-15

    Purpose: To determine whether readout-segmented echo-planar imaging (rs-EPI) diffusion-weighted imaging (DWI) can improve the image quality in patients with rectal cancer compared with single-shot echo-planar imaging (ss-EPI) DWI using 3.0 T magnetic resonance (MR) imaging. Materials and methods: This study was approved by the Institutional Review Board, and informed consent was obtained from all patients. Seventy-one patients with rectal cancer were enrolled in this study. For all patients, both rs-EPI and ss-EPI DWI were performed using a 3T MR scanner. Two radiologists independently assessed the overall image quality, lesion conspicuity, geometric distortion and distinction of anatomical structures. The signal-to-noise ratio (SNR), lesion contrast, contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) were also measured. Comparisons of the quantitative and qualitative parameters between the two sequences were performed using the paired t-test and the Wilcoxon signed rank test. Results: The scores of overall image quality, lesion conspicuity, geometric distortion and distinction of anatomical structures of rs-EPI were all significantly higher than those of ss-EPI (all p < 0.05). The SNR and CNR were higher in rs-EPI than those in ss-EPI (all p < 0.05). There was no significant difference between ss-EPI and rs-EPI with regard to ROI size and mean ADCs of the tumour (p = 0.574 and p = 0.479, respectively), but the mean ADC of the normal tissue was higher in rs-EPI than in ss-EPI (1.73 ± 0.30 × 10{sup −3} mm{sup 2}/s vs. 1.60 ± 0.31 × 10{sup −3} mm{sup 2}/s, p = 0.001). Conclusions: DW imaging based on readout-segmented echo-planar imaging is a clinically useful technique to improve the image quality for the purpose of evaluating lesions in patients with rectal tumours.

  7. Intrahepatic and hilar mass-forming cholangiocarcinoma: Qualitative and quantitative evaluation with diffusion-weighted MR imaging.

    Science.gov (United States)

    Fattach, Hassan El; Dohan, Anthony; Guerrache, Youcef; Dautry, Raphael; Boudiaf, Mourad; Hoeffel, Christine; Soyer, Philippe

    2015-08-01

    To qualitatively and quantitatively analyze the presentation of intrahepatic and hilar mass-forming cholangiocarcinoma with diffusion-weighted magnetic resonance imaging (DW-MRI). Twenty-eight patients with histopathologically proven mass-forming cholangiocarcinoma (hilar, n=17; intrahepatic, n=11) underwent hepatic DW-MRI at 1.5-T using free-breathing acquisition and three b-values (0,400,800s/mm(2)). Cholangiocarcinomas were evaluated qualitatively using visual analysis of DW-MR images and quantitatively with conventional ADC and normalized ADC measurements using liver and spleen as reference organs. All cholangiocarcinomas (28/28; 100%) were visible on DW-MR images. DW-MRI yielded best conspicuity of cholangiocarcinomas than the other MRI sequences (Philar cholangiocarcinomas. The use of normalized ADC using the liver as reference organ resulted in the most restricted distribution of ADC values of cholangiocarcinomas (variation coefficient=16.6%). There is a trend towards a common appearance of intrahepatic and hilar mass-forming cholangiocarcinomas on DW-MRI but variations may be observed. Familiarity with these variations may improve the diagnosis of mass-forming cholangiocarcinoma. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Clinical evaluation of single-shot and readout-segmented diffusion-weighted imaging in stroke patients at 3 T

    International Nuclear Information System (INIS)

    Morelli, John; Porter, David; Ai, Fei

    2013-01-01

    Background: Diffusion-weighted imaging (DWI) magnetic resonance imaging (MRI) is most commonly performed utilizing a single-shot echo-planar imaging technique (ss-EPI). Susceptibility artifact and image blur are severe when this sequence is utilized at 3 T. Purpose: To evaluate a readout-segmented approach to DWI MR in comparison with single-shot echo planar imaging for brain MRI. Material and Methods: Eleven healthy volunteers and 14 patients with acute and early subacute infarctions underwent DWI MR examinations at 1.5 and 3T with ss-EPI and readout-segmented echo-planar (rs-EPI) DWI at equal nominal spatial resolutions. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) calculations were made, and two blinded readers ranked the scans in terms of high signal intensity bulk susceptibility artifact, spatial distortions, image blur, overall preference, and motion artifact. Results: SNR and CNR were greatest with rs-EPI (8.1 ± 0.2 SNR vs. 6.0 ± 0.2; P -4 at 3T). Spatial distortions were greater with single-shot (0.23 ± 0.03 at 3T; P <0.001) than with rs-EPI (0.12 ± 0.02 at 3T). Combined with blur and artifact reduction, this resulted in a qualitative preference for the readout-segmented scans overall. Conclusion: Substantial image quality improvements are possible with readout-segmented vs. single-shot EPI - the current clinical standard for DWI - regardless of field strength (1.5 or 3 T). This results in improved image quality secondary to greater real spatial resolution and reduced artifacts from susceptibility in MR imaging of the brain

  9. Assessment of the link between quantitative biexponential diffusion-weighted imaging and contrast-enhanced MRI in the liver

    NARCIS (Netherlands)

    Dijkstra, Hildebrand; Oudkerk, Matthijs; Kappert, Peter; Sijens, Paul E.

    Purpose: To investigate if intravoxel incoherent motion (IVIM) modeled diffusion-weighted imaging (DWI) can be linked to contrast-enhanced (CE-)MRI in liver parenchyma and liver lesions. Methods: Twenty-five patients underwent IVIM-DWI followed by multiphase CE-MRI using Gd-EOB-DTPA (n = 20) or

  10. High and ultra-high b-value diffusion-weighted imaging in prostate cancer: a quantitative analysis.

    Science.gov (United States)

    Wetter, Axel; Nensa, Felix; Lipponer, Christine; Guberina, Nika; Olbricht, Tobias; Schenck, Marcus; Schlosser, Thomas W; Gratz, Marcel; Lauenstein, Thomas C

    2015-08-01

    Diffusion-weighted imaging (DWI) is routinely used in magnetic resonance imaging (MRI) of prostate cancer. However, the routine use of b values higher than 1000 s/mm(2) is not clear up to present. Moreover, the complex diffusion behavior of malignant and benign prostate tissues hampers precise predictions of contrast in DWI images and apparent diffusion coefficient (ADC) maps. To quantitatively analyze DWI with different b values in prostate cancer and to identify b values best suitable for cancer detection. Forty-one patients with histologically proven prostate cancer were examined with high resolution T2-weighted imaging and DWI at 3 Tesla. Five different b values (0, 800, 1000, 1500, 2000 s/mm(2)) were applied. ADC values of tumors and reference areas were measured on ADC maps derived from different pairs of b values. Furthermore, signal intensities of DW images of tumors and reference areas were measured. For analysis, contrast ratios of ADC values and signal intensities of DW images were calculated and compared. No significant differences were found between contrast ratios measured on ADC maps of all analyzed b value pairs (P = 0.43). Contrast ratios calculated from signal intensities of DW images were highest at b values of 1500 and 2000 s/mm(2) and differed significantly from contrast ratios at b values of 800 and 1000 s/mm(2) (P values, contrast ratios of DW images are significantly higher at b-values of 1500 and 2000 s/mm(2) in comparison to b values of 800 and 1000 s/mm(2). Therefore, diagnostic performance of DWI in prostate cancer might be increased by application of b values higher than 1000 s/mm(2). © The Foundation Acta Radiologica 2014.

  11. Clinical usefulness of diffusion-weighted imaging using low and high b-values to detect rectal cancer

    International Nuclear Information System (INIS)

    Hosonuma, Tomonori; Tozaki, Mitsuhiro; Ichiba, Noriatsu; Sakuma, Tohru; Hayashi, Daichi; Yanaga, Katsuhiko; Fukuda, Kunihiko

    2006-01-01

    The purpose of this study was to assess the potential role of diffusion-weighted imaging (DWI) using low and high b-values to detect rectal cancer. The subjects were 15 patients diagnosed endoscopically with rectal cancer (m in 1 patient, sm in 0, mp in 3, ss in 7, se in 1, a in 3) and 20 patients diagnosed endoscopically with colon cancer and no other lesions (control group). Magnetic resonance imaging was performed using a 1.5T system. DWI was performed in the axial plane using echo planar imaging sequence (repetition time/echo time 1200/66, field of view 306 X 350 mm, reconstruction matrix 156 x 256, pixel size 2.0 x 1.4 x 8.0 mm) and acquired with 2 b-values (50 and 800 s/mm 2 ). Low and high b-value DW images were analyzed visually. A lesion was positive by detection of a focal area of high signal in the rectum in high b-value images. The apparent diffusion coefficient (ADC) values of areas of high signal in high b-value images were calculated from the low and high b-value images. High b-value images enabled visualization of all 15 rectal cancers. In the control group, 13 cases were classified as negative and 7 cases as positive for rectal cancer. Sensitivity for detection of rectal cancer was 100% (15/15), and specificity was 65% (13/20). The mean ADC values in 7 patients with false-positive lesions and in 15 patients with rectal cancer were 1.374 x 10 -3 mm 2 /s (standard deviation [SD]: 0.157) and 1.194 x 10 -3 mm 2 /s (SD: 0.152), respectively (P=0.026). DWI with low and high b-values may be used to screen for rectal cancer. (author)

  12. Diffusion-weighted imaging in the diagnosis of enterovirus 71 encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Zhou-yang; Huang, Biao; Liang, Chang-hong (Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China)), Email: cjr.huangbiao@vip.163.com; He, Shaoru; Guo, Yuxiong (Department of Pediatrics, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China))

    2012-03-15

    Background. In the early phase of viral encephalitis, conventional MRI may appear normal. Diffusion-weighted imaging (DWI) is a sensitive tool for detecting early changes in cellular function in the central nervous system. Purpose. To investigate the usefulness of DWI in the diagnosis of enterovirus 71 (EV71) encephalitis, and to determine whether DWI is superior to conventional MR sequences. Material and Methods. MRI scans in 26 patients were retrospectively evaluated for distribution of lesions on T1-weighted images (T1WI), T2-weighted images (T2WI), fluid-attenuated inversion recovery (FLAIR), and DWI. Contrast-to-noise ratios (CNRs) were calculated for all regions on each sequence and differences in the four MRI sequences were assessed using CNRs. Apparent diffusion coefficient (ADC) values were measured for all regions to look for true restriction of diffusion. Results. Fifteen out of 26 cases showed positive findings on MR imaging. The brain stem was involved in 11 patients, cortex and subcortical white matter in four patients. DWI was more sensitive in detecting the abnormalities (89.7%) compared to T2WI (48.7%), FLAIR (41.0%), and T1WI (35.9%), and the positive ratio of DWI was significantly higher compared to other sequences. Furthermore, no significant difference was found between T2WI and FLAIR (P 0.649). The corresponding mean CNRs were 8.73 +- 2.57, 83.59 +- 29.28, 24.22 +- 6.22, and 132.27 +- 78.32 on T1WI, T2WI, FLAIR, and DWI, respectively. The absolute values of CNRs of lesions on DWI were significantly greater than those on other sequences. Conclusion. DWI appears to be more sensitive in detecting EV71 encephalitis than conventional MRI sequences. This capability may improve the accuracy in diagnosing EV71 encephalitis, especially at the early stage

  13. Diffusion-weighted imaging in the diagnosis of enterovirus 71 encephalitis

    International Nuclear Information System (INIS)

    Lian, Zhou-yang; Huang, Biao; Liang, Chang-hong; He, Shaoru; Guo, Yuxiong

    2012-01-01

    Background. In the early phase of viral encephalitis, conventional MRI may appear normal. Diffusion-weighted imaging (DWI) is a sensitive tool for detecting early changes in cellular function in the central nervous system. Purpose. To investigate the usefulness of DWI in the diagnosis of enterovirus 71 (EV71) encephalitis, and to determine whether DWI is superior to conventional MR sequences. Material and Methods. MRI scans in 26 patients were retrospectively evaluated for distribution of lesions on T1-weighted images (T1WI), T2-weighted images (T2WI), fluid-attenuated inversion recovery (FLAIR), and DWI. Contrast-to-noise ratios (CNRs) were calculated for all regions on each sequence and differences in the four MRI sequences were assessed using CNRs. Apparent diffusion coefficient (ADC) values were measured for all regions to look for true restriction of diffusion. Results. Fifteen out of 26 cases showed positive findings on MR imaging. The brain stem was involved in 11 patients, cortex and subcortical white matter in four patients. DWI was more sensitive in detecting the abnormalities (89.7%) compared to T2WI (48.7%), FLAIR (41.0%), and T1WI (35.9%), and the positive ratio of DWI was significantly higher compared to other sequences. Furthermore, no significant difference was found between T2WI and FLAIR (P 0.649). The corresponding mean CNRs were 8.73 ± 2.57, 83.59 ± 29.28, 24.22 ± 6.22, and 132.27 ± 78.32 on T1WI, T2WI, FLAIR, and DWI, respectively. The absolute values of CNRs of lesions on DWI were significantly greater than those on other sequences. Conclusion. DWI appears to be more sensitive in detecting EV71 encephalitis than conventional MRI sequences. This capability may improve the accuracy in diagnosing EV71 encephalitis, especially at the early stage

  14. Clinico-radiological features of subarachnoid hyperintensity on diffusion-weighted images in patients with meningitis

    International Nuclear Information System (INIS)

    Kawaguchi, T.; Sakurai, K.; Hara, M.; Muto, M.; Nakagawa, M.; Tohyama, J.; Oguri, T.; Mitake, S.; Maeda, M.; Matsukawa, N.; Ojika, K.; Shibamoto, Y.

    2012-01-01

    Aim: To investigate the clinical and radiological features of meningitis with subarachnoid diffusion-weighted imaging (DWI) hyperintensity. Materials and methods: The clinical features, laboratory data, and radiological findings, including the number and distribution of subarachnoid DWI hyperintense lesions and other radiological abnormalities, of 18 patients seen at five institutions were evaluated. Results: The patients consisted of eight males and 10 females, whose ages ranged from 4 months to 82 years (median 65 years). Causative organisms were bacteria in 15 patients, including Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus agalactiae, Staphylococcus aureus, Klebsiella pneumoniae, and Listeria monocytogenes. The remaining three were fungal meningitis caused by Cryptococcus neoformans. Subarachnoid DWI hyperintense lesions were multiple in 16 of the 18 cases (89%) and predominantly distributed around the frontal lobe in 16 of the 18 cases (89%). In addition to subarachnoid abnormality, subdural empyema, cerebral infarction, and intraventricular empyema were found in 50, 39, and 39%, respectively. Compared with paediatric patients, adult patients with bacterial meningitis tended to have poor prognoses (7/10 versus 1/5; p = 0.1). Conclusion: Both bacterial and fungal meningitis could cause subarachnoid hyperintensity on DWI, predominantly around the frontal lobe. This finding is often associated with poor prognosis in adult bacterial meningitis.

  15. Bright intracranial lesions on diffusion-weighted images: a pictorial review

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Dae Seob [Gyeongsang National University College of Medicine, Jinju (Korea, Republic of)

    2006-06-15

    Diffusion-weighted imaging (DWI) is a MR sequence that is used to evaluate the rate of microscopic water diffusion within the tissues. The ability to measure the rate of water diffusion is important because this is frequently altered in various disease processes. Generally, the lesions with restricted water diffusion show bright intensity on DWI, but the lesions without restricted water diffusion can also show bright intensity on DWI, which is called the 'T2 shine through effect'. With DWI, we can sensitively detect hyperacute infarction (within 6 hours after symptom onset), and this is difficult to detect with using CT and the conventional MR sequenced. The acute and subacute lesions of hypoxic-ischemic encephalopathy and carbon monoxide intoxication also show bright intensity on the DWI. The other diseases that can show bright intensity on the DWI include acute and subacute diffuse axonal injury lesion, hyperacute and late subacute hematomas, cerebral abscess, subdural empyema, acute herpes encephalitis, various tumors and such degenerative and demyelinating diseases as multiple sclerosis, posterior reversible encephalopathy syndrome, Wilson's disease and Wernicke's encephalopathy.

  16. Bright intracranial lesions on diffusion-weighted images: a pictorial review

    International Nuclear Information System (INIS)

    Choi, Dae Seob

    2006-01-01

    Diffusion-weighted imaging (DWI) is a MR sequence that is used to evaluate the rate of microscopic water diffusion within the tissues. The ability to measure the rate of water diffusion is important because this is frequently altered in various disease processes. Generally, the lesions with restricted water diffusion show bright intensity on DWI, but the lesions without restricted water diffusion can also show bright intensity on DWI, which is called the 'T2 shine through effect'. With DWI, we can sensitively detect hyperacute infarction (within 6 hours after symptom onset), and this is difficult to detect with using CT and the conventional MR sequenced. The acute and subacute lesions of hypoxic-ischemic encephalopathy and carbon monoxide intoxication also show bright intensity on the DWI. The other diseases that can show bright intensity on the DWI include acute and subacute diffuse axonal injury lesion, hyperacute and late subacute hematomas, cerebral abscess, subdural empyema, acute herpes encephalitis, various tumors and such degenerative and demyelinating diseases as multiple sclerosis, posterior reversible encephalopathy syndrome, Wilson's disease and Wernicke's encephalopathy

  17. Optimising diffusion weighted MRI for imaging metastatic and myeloma bone disease and assessing reproducibility

    International Nuclear Information System (INIS)

    Messiou, C.; Collins, D.J.; Morgan, V.A.; DeSouza, N.M.

    2011-01-01

    To establish normal bone marrow values of apparent diffusion coefficient (ADC) over an age range, compare them with metastatic and myelomatous involvement, to establish reproducibility and to optimise b values. The ADCs of bone marrow in 7 volunteers (mean age 29.7 years), 34 volunteers (mean age 63.3 years) and 43 patients with metastatic and myelomatous involvement (mean age 65.5 years) were measured. In 9 volunteers diffusion weighted MRI was repeated within 7 days. b values were derived to optimise contrast between normal and pathological marrow. The mean ADC of bone marrow in younger volunteers was significantly higher than that of older volunteers. The coefficient of reproducibility was 14.8%. The ADC mean of metastatic and myeloma bone disease was 1054+/-456 x 10 -6 mm 2 s -1 . An ADC threshold of 655 x 10 -6 mm 2 s -1 separated normal and abnormal marrow with a sensitivity and specificity of 90% and 93% respectively. Contrast between normal and abnormal marrow was optimal at b = 1389 smm -2 . The reproducibility of ADC measurements in bone is equivalent to published data for soft tissue with a high sensitivity and specificity for separating abnormal from age matched normal bone marrow. A b value of around 1,400 smm -2 is optimal for imaging bone marrow. (orig.)

  18. Optimization of b-value distribution for biexponential diffusion-weighted MR imaging of normal prostate.

    Science.gov (United States)

    Jambor, Ivan; Merisaari, Harri; Aronen, Hannu J; Järvinen, Jukka; Saunavaara, Jani; Kauko, Tommi; Borra, Ronald; Pesola, Marko

    2014-05-01

    To determine the optimal b-value distribution for biexponential diffusion-weighted imaging (DWI) of normal prostate using both a computer modeling approach and in vivo measurements. Optimal b-value distributions for the fit of three parameters (fast diffusion Df, slow diffusion Ds, and fraction of fast diffusion f) were determined using Monte-Carlo simulations. The optimal b-value distribution was calculated using four individual optimization methods. Eight healthy volunteers underwent four repeated 3 Tesla prostate DWI scans using both 16 equally distributed b-values and an optimized b-value distribution obtained from the simulations. The b-value distributions were compared in terms of measurement reliability and repeatability using Shrout-Fleiss analysis. Using low noise levels, the optimal b-value distribution formed three separate clusters at low (0-400 s/mm2), mid-range (650-1200 s/mm2), and high b-values (1700-2000 s/mm2). Higher noise levels resulted into less pronounced clustering of b-values. The clustered optimized b-value distribution demonstrated better measurement reliability and repeatability in Shrout-Fleiss analysis compared with 16 equally distributed b-values. The optimal b-value distribution was found to be a clustered distribution with b-values concentrated in the low, mid, and high ranges and was shown to improve the estimation quality of biexponential DWI parameters of in vivo experiments. Copyright © 2013 Wiley Periodicals, Inc.

  19. Evaluation of diffusion weighted imaging in differentiating prostate cancer and benign hyperplasia

    International Nuclear Information System (INIS)

    Wang Ximing; Guo Liang; Zhang Yu; Bai Renju; Zhao Xin

    2006-01-01

    Objective: To describe diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) map appearance of benign hyperplasia (BPH) and prostate cancer(PCa), and to evaluate DWI and ADC map and ADC values in differential diagnosis of PCa. Methods: DWI and ADC map findings were reviewed in 18 BPH cases and 25 PCa cases. ADC values of PCa and ADC values of peripheral zone (PZ) and central glands (CG) voxels in BPH were retrospectively measured. Results: On DWI, PZ of BPH demonstrated homogenous slightly signal intensity (SI), CG appeared heterogeneous SI. Twenty-two PCa showed markedly high-signal on DWI and obviously low-signal on ADC map, which both could clearly demonstrate the area of PCa. The invaded seminal vesicles and bone metastases of pelvis also appear similar SI as PCa on DWI and ADC map. ADC values of PCa were significantly lower than PZ(t=-52.46, P -3 mm 2 /s] and PZ in BPH [(1.27±0.14) x 10 -3 mm 2 /s], only minimal overlap (1/127, 0.7%) existed between ADC values of PCa and CG in BPH[(0.96±0.14) x 10 -3 mm 2 /s]. Conclusion: Both DWI and ADC map can well display PCa location and area, which also can show the involvement of seminal vesicles and bone metastases. BPH and PCa can be differentiated by Both DWI and ADC map and ADC values. (authors)

  20. Diffusion-weighted imaging of the kidneys in haemolytic uraemic syndrome

    International Nuclear Information System (INIS)

    Herrmann, Jochen; Wenzel, Ulrich; Galler, Stephanie; Schoennagel, Bjoern P.; Bannas, Peter; Yamamura, Jin; Groth, Michael; Adam, Gerhard; Busch, Jasmin D.; Tozakidou, Magdalini; Petersen, Kay U.; Joekel, Michaela; Habermann, Christian R.

    2017-01-01

    To evaluate the kidneys of patients with haemolytic uraemic syndrome (HUS) using diffusion-weighted imaging (DWI) and Doppler ultrasound (US) compared with healthy controls. Fifteen patients (mean age 33.3 years; three male; 12 female) with diarrhoea-positive HUS and 15 healthy volunteers were prospectively evaluated with DWI and Doppler US. A total apparent diffusion coefficient (ADC TOT ), and ADCs predominantly reflecting microperfusion (ADC LOW ) and diffusion (ADC HIGH ) were calculated. Doppler US evaluated renal vascularity and flow. When compared with controls, kidneys affected by HUS showed reduced cortical ADC values (ADC TOT 1.79±0.22 vs. 2.04±0.1x10 -3 mm 2 /s, P 0.001), resulting in either low corticomedullary differences (11/15 patients) or an inverted corticomedullary pattern (4/15 patients). Reduction of cortical ADC values was associated with a decrease of cortical vascularity on Doppler US (ADC TOT , P<0.001; ADC LOW , P 0.047). Kidneys with complete absence of the cortical vasculature on Doppler US (four patients) also demonstrated limited diffusion (ADC HIGH , P 0.002). Low glomerular filtration rate, requirement for haemodialysis during hospitalization, and longer duration of haemodialysis were associated with decreased cortical diffusivity (ADC TOT: P 0.04, 0.007, and <0.001, respectively). DWI shows qualitative and quantitative abnormalities in kidneys affected by HUS, thereby extending the non-invasive assessment of renal parenchymal damage. (orig.)

  1. Evaluation of renal allograft function early after transplantation with diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    Eisenberger, Ute; Frey, Felix J.; Thoeny, Harriet C.; Binser, Tobias; Boesch, Chris; Gugger, Mathias; Vermathen, Peter

    2010-01-01

    To determine the inter-patient variability of apparent diffusion coefficients (ADC) and concurrent micro-circulation contributions from diffusion-weighted MR imaging (DW-MRI) in renal allografts early after transplantation, and to obtain initial information on whether these measures are altered in histologically proven acute allograft rejection (AR). DW-MRI was performed in 15 renal allograft recipients 5-19 days after transplantation. Four patients presented with AR and one with acute tubular necrosis (ATN). Total ADC (ADC T ) was determined, which includes diffusion and micro-circulation contributions. Furthermore, diffusion and micro-circulation contributions were separated, yielding the ''perfusion fraction'' (F P ), and ''perfusion-free'' diffusion (ADC D ). Diffusion parameters in the ten allografts with stable function early after transplantation demonstrated low variabilities. Values for ADC T and ADC D were (x 10 -5 mm 2 /s) 228 ± 14 and 203 ± 9, respectively, in cortex and 226 ± 16 and 199 ± 9, respectively, in medulla. F P values were 18 ± 5% in cortex and 19 ± 5% in medulla. F P values were strongly reduced to less than 12% in cortex and medulla of renal transplants with AR and ATN. F P values correlated with creatinine clearance. DW-MRI allows reliable determination of diffusion and micro-circulation contributions in renal allografts shortly after transplantation; deviations in AR indicate potential clinical utility of this method to non-invasively monitor derangements in renal allografts. (orig.)

  2. Acute hyperammonemic encephalopathy with features on diffusion-weighted images: Report of two cases

    International Nuclear Information System (INIS)

    Kim, Ja Young; Yu, In Kyu

    2015-01-01

    Acute hyperammonemic encephalopathy is a rare toxic encephalopathy caused by accumulated plasma ammonia. A few literatures are reported about MRI findings of acute hyperammonemic encephalopathy. It is different from the well-known chronic hepatic encephalopathy. The clinical symptom and MRI findings of acute hyperammonemic encephalopathy can be reversible with proper treatment. Acute hepatic encephalopathy involves the cingulate cortex, diffuse cerebral cortices, insula, bilateral thalami on diffusion-weighted imaging (DWI), and fluid-attenuated inversion-recovery. Acute hepatic encephalopathy might mimic hypoxic-ischemic encephalopathy because of their similar predominant involving sites. We experienced 2 cases of acute hyperammonemic encephalopathy consecutively. They showed restricted diffusion at the cingulate cortex, cerebral cortices, insula, and bilateral dorsomedial thalami on DWI. One patient underwent acute fulminant hepatitis A, the other patient with underlying chronic liver disease had acute liver failure due to hepatotoxicity of tuberculosis medication. In this report, we presented the characteristic features of DWI in acute hyperammonemic encephalopathy. In addition, we reviewed articles on MRI findings of acute hyperammonemic encephalopathy.

  3. Optimising diffusion weighted MRI for imaging metastatic and myeloma bone disease and assessing reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Messiou, C. [Institute of Cancer Research and Royal Marsden, NHS Foundation Trust, Cancer Research UK Clinical Magnetic Resonance Research Group, Surrey (United Kingdom); Institute of Cancer Research and Royal Marsden, NHS Foundation Trust, MRI Department, Surrey (United Kingdom); Collins, D.J.; Morgan, V.A.; DeSouza, N.M. [Institute of Cancer Research and Royal Marsden, NHS Foundation Trust, Cancer Research UK Clinical Magnetic Resonance Research Group, Surrey (United Kingdom)

    2011-08-15

    To establish normal bone marrow values of apparent diffusion coefficient (ADC) over an age range, compare them with metastatic and myelomatous involvement, to establish reproducibility and to optimise b values. The ADCs of bone marrow in 7 volunteers (mean age 29.7 years), 34 volunteers (mean age 63.3 years) and 43 patients with metastatic and myelomatous involvement (mean age 65.5 years) were measured. In 9 volunteers diffusion weighted MRI was repeated within 7 days. b values were derived to optimise contrast between normal and pathological marrow. The mean ADC of bone marrow in younger volunteers was significantly higher than that of older volunteers. The coefficient of reproducibility was 14.8%. The ADC mean of metastatic and myeloma bone disease was 1054+/-456 x 10{sup -6} mm{sup 2}s{sup -1}. An ADC threshold of 655 x 10{sup -6} mm{sup 2}s{sup -1} separated normal and abnormal marrow with a sensitivity and specificity of 90% and 93% respectively. Contrast between normal and abnormal marrow was optimal at b = 1389 smm{sup -2}. The reproducibility of ADC measurements in bone is equivalent to published data for soft tissue with a high sensitivity and specificity for separating abnormal from age matched normal bone marrow. A b value of around 1,400 smm{sup -2} is optimal for imaging bone marrow. (orig.)

  4. MR diffusion weighted imaging of the prostate adenocarcinoma after endocrinotherapy: preliminary results

    International Nuclear Information System (INIS)

    Chen Zhiqiang; Wang Xiaoying; Li Feiyu; Guo Xuemei; Jiang Xuexiang; Guo Yulin

    2007-01-01

    Objective: To assess the changes of the apparent diffusion coefficient (ADC) values of cancerous and noncancerous regions of prostate peripheral zone in prostate cancer patients with and without endocrinotherapy. Methods: Diffusion-weighted echo-planar imaging (EPI) were performed in 32 patients with diagnosed prostate cancer, including 18 patients who were treated with endocrinotherapy over 6 months and 14 untreated matched control patients. According to the pathological results obtained by ultrasound guided biopsy, the locations of the prostate cancerous regions were marked at one or more of the sextants. The ADC values of the bladder and the obturator internus were also measured. Results: The mean ADC values of cancerous and noncancerous regions in 14 untreated controls were (1.22±0.25) x 10 -3 , (1.59 ± 0.19) x 10 -3 mm 2 /s, respectively (t=7.03, P -3 mm 2 /s in noncancerous regions, but increased to (1.46 ± 0.30) x 10 -3 mm 2 /s in cancerous regions. There still had significant difference between the cancerous and the noncancerous regions (t=2.46, P 0.05), in bladder and the obturator internus (t=0.48, 1.64; P>0.05). Conclusion: Measurement of ADCs might be useful to evaluate the efficacy of endocrinotherapy for patients with prostate cancer. (authors)

  5. Value of diffusion-Weighted imaging in evaluating the cellularity density of prostate cancer

    International Nuclear Information System (INIS)

    Liu Jingang; Wang Xizhen; Wang Bin; Niu Qingliang; Liu Qiang

    2008-01-01

    Objective: To study the cellularity density of prostate cancer (PCa) with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC). Methods: 38 patients with histologically proven prostate cancer (PCa) underwent DWI with a 1.5 T MR scanner using a pelvic phased array multi-coil. The ADC values of PCa, benign prostatic hyperplasia (BPH), and peripheral zone (PZ) were calculated. The cellularity density of PCa was recorded according to hematoxylin and eosin (HE) staining. The relationship between ADC value and cellularity density of PCa was analyzed with Pearson correlation coefficient. Results: The ADC values of PCa, BPH, and PZ were (49.32±12.68)×10 -5 mm 2 /s, (86.73±26.75)×10 -5 mm 2 /s and (126.25±27.21)×10 -5 mm 2 /s, respectively. The ADC value of PCa was significantly lower than that of BPH and PZ (P<005). The cellularity density of PCa was 12.9%. The ADC value reversely related to the cellularity density of prostate cancer (r=-0.646, P<005). Conclusion: The ADC value can reflect the cellularity density of PCa. (authors)

  6. High b-value diffusion-weighted imaging in progressive multifocal leukoencephalopathy in HIV patients

    International Nuclear Information System (INIS)

    Godi, Claudia; De Vita, Enrico; Davagnanam, Indran; Tombetti, Enrico; Haddow, Lewis; Jaeger, Hans Rolf

    2017-01-01

    An ill-defined hyperintense edge and hypointense core on diffusion-weighted imaging (DWI) is typical of progressive multifocal leukoencephalopathy (PML). We aimed to investigate whether a b-value of 3,000 s/mm"2 (b3000) can improve visualisation of PML, or provide different structural information compared to 1,000 s/mm"2 (b1000). We retrospectively identified HIV-positive patients with confirmed PML studied under a clinical protocol including both b1000 and b3000 DWI. The rim and core of each PML lesion and normal-appearing white matter (NAWM) were outlined on trace-weighted DWI. Signal intensities, apparent diffusion coefficient (ADC) values and volumes were measured and compared between b1000 and b3000. Nine lesions from seven patients were analysed. The rim and core were better visualised on b3000, with higher signal of the rim and lower signal of the core compared to NAWM. The hyperintense rim had non-restricted average ADCs, but included foci of low ADC on both b3000 and b1000. Despite similar total lesion volumes, b3000 displayed significantly larger core and smaller rim volumes than b1000. b3000 improves visualisation of this important PML hallmark. Moreover, b3000 partly reclassifies tissue from rim into core, and might provide potentially more accurate biomarkers of PML activity and prognosis. (orig.)

  7. High b-value diffusion-weighted imaging in progressive multifocal leukoencephalopathy in HIV patients

    Energy Technology Data Exchange (ETDEWEB)

    Godi, Claudia [San Raffaele Scientific Institute, Neuroradiology Department, Milan (Italy); The National Hospital for Neurology and Neurosurgery, Lysholm Department of Neuroradiology, London (United Kingdom); UCL Institute of Neurology, Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, London (United Kingdom); De Vita, Enrico; Davagnanam, Indran [The National Hospital for Neurology and Neurosurgery, Lysholm Department of Neuroradiology, London (United Kingdom); UCL Institute of Neurology, Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, London (United Kingdom); Tombetti, Enrico [Vita-Salute San Raffaele University, Milan (Italy); Haddow, Lewis [University College London, Centre for Sexual Health and HIV Research, Research Department of Infection and Population Health, London (United Kingdom); Jaeger, Hans Rolf [The National Hospital for Neurology and Neurosurgery, Lysholm Department of Neuroradiology, London (United Kingdom); UCL Institute of Neurology, Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, London (United Kingdom); University College Hospital, Centre of Medical Imaging, London (United Kingdom)

    2017-09-15

    An ill-defined hyperintense edge and hypointense core on diffusion-weighted imaging (DWI) is typical of progressive multifocal leukoencephalopathy (PML). We aimed to investigate whether a b-value of 3,000 s/mm{sup 2} (b3000) can improve visualisation of PML, or provide different structural information compared to 1,000 s/mm{sup 2} (b1000). We retrospectively identified HIV-positive patients with confirmed PML studied under a clinical protocol including both b1000 and b3000 DWI. The rim and core of each PML lesion and normal-appearing white matter (NAWM) were outlined on trace-weighted DWI. Signal intensities, apparent diffusion coefficient (ADC) values and volumes were measured and compared between b1000 and b3000. Nine lesions from seven patients were analysed. The rim and core were better visualised on b3000, with higher signal of the rim and lower signal of the core compared to NAWM. The hyperintense rim had non-restricted average ADCs, but included foci of low ADC on both b3000 and b1000. Despite similar total lesion volumes, b3000 displayed significantly larger core and smaller rim volumes than b1000. b3000 improves visualisation of this important PML hallmark. Moreover, b3000 partly reclassifies tissue from rim into core, and might provide potentially more accurate biomarkers of PML activity and prognosis. (orig.)

  8. Ischemic lesions related to cerebral angiography: Evaluation by diffusion weighted MR imaging

    International Nuclear Information System (INIS)

    Kato, Koki; Tomura, Noriaki; Takahashi, Satoshi; Sakuma, Ikuo; Watarai, Jiro

    2003-01-01

    We examined the incidence of ischemic lesions occurring after cerebral angiography by means of diffusion weighted MR imaging (DWI). Fifty patients were included in this study. Balloon occlusion tests of the internal carotid artery were performed in 9 of the 50 patients. DWI was performed on the same day as the cerebral angiography or on the following day. No new neurological deficits were found after cerebral angiography. However, 13 of the 50 cases revealed new ischemic lesions after cerebral angiography. The incidence of ischemic lesions was significantly different between patients who underwent balloon occlusion tests and patients who did not. The incidence of ischemic lesions was not influenced by the duration of the procedure, use of additional catheters, total amount of contrast material or the type of contrast material. The incidence of clinically silent ischemic lesions related to cerebral angiography is greater than the incidence of neurological complications. In patients who underwent occlusion tests of the internal carotid artery, the incidence of silent lesions was significantly higher than in patients who did not. (orig.)

  9. Acute hyperammonemic encephalopathy with features on diffusion-weighted images: Report of two cases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ja Young; Yu, In Kyu [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

    2015-02-15

    Acute hyperammonemic encephalopathy is a rare toxic encephalopathy caused by accumulated plasma ammonia. A few literatures are reported about MRI findings of acute hyperammonemic encephalopathy. It is different from the well-known chronic hepatic encephalopathy. The clinical symptom and MRI findings of acute hyperammonemic encephalopathy can be reversible with proper treatment. Acute hepatic encephalopathy involves the cingulate cortex, diffuse cerebral cortices, insula, bilateral thalami on diffusion-weighted imaging (DWI), and fluid-attenuated inversion-recovery. Acute hepatic encephalopathy might mimic hypoxic-ischemic encephalopathy because of their similar predominant involving sites. We experienced 2 cases of acute hyperammonemic encephalopathy consecutively. They showed restricted diffusion at the cingulate cortex, cerebral cortices, insula, and bilateral dorsomedial thalami on DWI. One patient underwent acute fulminant hepatitis A, the other patient with underlying chronic liver disease had acute liver failure due to hepatotoxicity of tuberculosis medication. In this report, we presented the characteristic features of DWI in acute hyperammonemic encephalopathy. In addition, we reviewed articles on MRI findings of acute hyperammonemic encephalopathy.

  10. Clinico-radiological features of subarachnoid hyperintensity on diffusion-weighted images in patients with meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, T., E-mail: madarafuebuki@yahoo.co.jp [Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Sakurai, K.; Hara, M. [Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Muto, M. [Department of Radiology, Okazaki City Hospital, Okazaki, Aichi (Japan); Nakagawa, M. [Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Tohyama, J. [Department of Radiology, Toyota-kai Medical Corporation Kariya Toyota General Hospital, Kariya, Aichi (Japan); Oguri, T. [Department of Neurology and Neuroscience, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Mitake, S. [Department of Neurology, Tosei General Hospital, Seto-shi, Aichi (Japan); Maeda, M. [Department of Radiology, Mie University School of Medicine, Tsu, Mie (Japan); Matsukawa, N.; Ojika, K. [Department of Neurology and Neuroscience, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Shibamoto, Y. [Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan)

    2012-04-15

    Aim: To investigate the clinical and radiological features of meningitis with subarachnoid diffusion-weighted imaging (DWI) hyperintensity. Materials and methods: The clinical features, laboratory data, and radiological findings, including the number and distribution of subarachnoid DWI hyperintense lesions and other radiological abnormalities, of 18 patients seen at five institutions were evaluated. Results: The patients consisted of eight males and 10 females, whose ages ranged from 4 months to 82 years (median 65 years). Causative organisms were bacteria in 15 patients, including Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus agalactiae, Staphylococcus aureus, Klebsiella pneumoniae, and Listeria monocytogenes. The remaining three were fungal meningitis caused by Cryptococcus neoformans. Subarachnoid DWI hyperintense lesions were multiple in 16 of the 18 cases (89%) and predominantly distributed around the frontal lobe in 16 of the 18 cases (89%). In addition to subarachnoid abnormality, subdural empyema, cerebral infarction, and intraventricular empyema were found in 50, 39, and 39%, respectively. Compared with paediatric patients, adult patients with bacterial meningitis tended to have poor prognoses (7/10 versus 1/5; p = 0.1). Conclusion: Both bacterial and fungal meningitis could cause subarachnoid hyperintensity on DWI, predominantly around the frontal lobe. This finding is often associated with poor prognosis in adult bacterial meningitis.

  11. Utility of diffusion-weighted imaging in the diagnosis of acute appendicitis

    Energy Technology Data Exchange (ETDEWEB)

    Inci, Ercan; Hocaoglu, Elif; Aydin, Sibel; Bayramoglu, Sibel; Cimilli, Tan [Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Department of Radiology, Istanbul (Turkey); Kilickesmez, Ozgur [Yeditepe University, School of Medicine, Department of Radiology, Istanbul (Turkey)

    2011-04-15

    To evaluate the value of diffusion-weighted MRI (DWI) in the diagnosis of acute appendicitis. 119 patients with acute appendicitis and 50 controls were enrolled in this prospective study. DWI was obtained with b factors 0, 500 and 1000 s/mm{sup 2} and were assessed with a visual scoring system by two radiologists followed by quantitative evaluation of the DW images and ADC maps. Histopathology revealed appendicitis in 79/92 patients (78%) who had undergone surgery. On visual evaluation, except for one patient with histopathologically proven appendicitis all inflamed appendixes were hyperintense on DWI (98.7%). Quantitative evaluation with DW signal intensities and ADC values revealed a significant difference with normal and inflamed appendixes (p < 0.001). The best discriminative parameter was signal intensity (b 500). With a cut-off value of 56 for the signal intensity the ratio had a sensitivity of 99% and a specificity of 97%. The cut-off ADC value at 1.66 mm{sup 2}/s had a sensitivity of 97% and a specificity of 99%. DWI is a valuable technique for the diagnosis of acute appendicitis with both qualitative and quantitative evaluation. DWI increases the conspicuity of the inflamed appendix. We recommend using DWI to diagnose acute appendicitis. (orig.)

  12. Utility of diffusion-weighted imaging in the diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Inci, Ercan; Hocaoglu, Elif; Aydin, Sibel; Bayramoglu, Sibel; Cimilli, Tan; Kilickesmez, Ozgur

    2011-01-01

    To evaluate the value of diffusion-weighted MRI (DWI) in the diagnosis of acute appendicitis. 119 patients with acute appendicitis and 50 controls were enrolled in this prospective study. DWI was obtained with b factors 0, 500 and 1000 s/mm 2 and were assessed with a visual scoring system by two radiologists followed by quantitative evaluation of the DW images and ADC maps. Histopathology revealed appendicitis in 79/92 patients (78%) who had undergone surgery. On visual evaluation, except for one patient with histopathologically proven appendicitis all inflamed appendixes were hyperintense on DWI (98.7%). Quantitative evaluation with DW signal intensities and ADC values revealed a significant difference with normal and inflamed appendixes (p 2 /s had a sensitivity of 97% and a specificity of 99%. DWI is a valuable technique for the diagnosis of acute appendicitis with both qualitative and quantitative evaluation. DWI increases the conspicuity of the inflamed appendix. We recommend using DWI to diagnose acute appendicitis. (orig.)

  13. Quantifying Pathology in Diffusion Weighted MRI

    NARCIS (Netherlands)

    Caan, M.W.A.

    2010-01-01

    In this thesis algorithms are proposed for quantification of pathology in Diffusion Weighted Magnetic Resonance Imaging (DW-MRI) data. Functional evidence for brain diseases can be explained by specific structural loss in the white matter of the brain. That is, certain biomarkers may exist where the

  14. Utility of diffusion-weighted MR imaging in the diagnosis of placenta accreta spectrum abnormality.

    Science.gov (United States)

    Sannananja, Bhagya; Ellermeier, Anna; Hippe, Daniel S; Winter, Thomas C; Kang, Stella K; Lee, Susanna I; Kilgore, Mark R; Dighe, Manjiri K

    2018-04-17

    The aim of this study was to evaluate the utility of added DWI sequences as an adjunct to traditional MR imaging in the evaluation of abnormal placentation in patients with suspicion for placenta accreta spectrum abnormality or morbidly adherent placenta (MAP). The study was approved by local ethics committee. The subjects included pregnant women with prenatal MRI performed between July 2013 to July 2015. All imaging was performed on a Philips 1.5T MR scanner using pelvic phased-array coil. Only T2-weighted and diffusion-weighted imaging (DWI) series were compiled for review. Two randomized imaging sets were created: set 1 included T2-weighted series only (T2W); set 2 included T2W with DWI series together (T2W + DWI). Three radiologists, blinded to history and pathology, reviewed the imaging, with 2 weeks of time between the two image sets. Sensitivity, specificity, and overall accuracy for MAP were calculated and compared between T2W only and T2W + DWI reads. Associations between imaging findings and invasion on pathology were tested using the Chi-squared test. Confidence scores, inter-reader agreement, and systematic differences were documented. A total of 17 pregnant women were included in the study. 8 cases were pathologically diagnosed with MAP. There were no significant differences in the diagnostic accuracy between T2W and T2W + DWI in the diagnosis of MAP in terms of overall accuracy (62.7% for T2W vs. 68.6% for T2W + DWI, p = 0.68), sensitivity (70.8% for T2W vs. 95.8% for T2W + DWI, p = 0.12), and specificity (55.6% for T2W vs. 44.4% for T2W + DWI, p = 0.49). There was no significant difference in the diagnostic confidence between the review of T2W images alone and the T2W + DWI review (mean 7.3 ± 1.8 for T2W vs. 7.5 ± 1.8 for T2W + DWI, p = 0.37). With the current imaging technique, addition of DWI sequence to the traditional T2W images cannot be shown to significantly increase the accuracy or