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Sample records for serial diffusion-weighted mri

  1. Serial diffusion-weighted MRI correlates with clinical course and treatment response in children with intracranial pus collections

    International Nuclear Information System (INIS)

    Fanning, Noel F.; Laffan, Eoghan E.; Shroff, Manohar M.

    2006-01-01

    Accurate assessment of treatment response in children with intracranial pus collections is vital to guide appropriate therapy and reduce morbidity and mortality. To correlate serial MR-measurable changes in diffusion-weighted imaging (DWI) with clinical response to treatment. We retrospectively reviewed clinical notes, conventional MR sequences and DWI in eight children with intracranial pus collections. Trace DWI signal intensity and apparent diffusion coefficient (ADC) values were compared at three time points: at initial diagnosis (eight children, 13 collections), at follow-up during continued clinical infection (three children, sp collections), and at follow-up when clinical infection had resolved (seven children, 12 collections). At initial diagnosis all patients were septic and collections showed restricted diffusion (mean ADC 0.61±0.15 x 10 -3 mm 2 /s). Patients with persistent clinical sepsis at follow-up DWI had collections with persistent low ADC values (0.66±0.21 x 10 -3 mm 2 /s), significantly (P -3 mm 2 /s, P<0.01) compared both to patients with signs of continued sepsis and to normal gray matter values. Persistent restricted diffusion in pus collections correlates with continued sepsis. Treatment response is associated with clinical resolution of sepsis and ADC value elevation significantly above normal gray matter values. (orig.)

  2. 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.)

  3. 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

  4. Diffusion-weighted MRI of the prostate

    International Nuclear Information System (INIS)

    Mueller-Lisse, U.G.; Scherr, M.K.; Mueller-Lisse, U.L.; Zamecnik, P.; Schlemmer, H.P.W.

    2011-01-01

    Diffusion-weighted magnetic resonance imaging (DWI) can complement MRI of the prostate in the detection and localization of prostate cancer, particularly after previous negative biopsy. A total of 13 original reports and 2 reviews published in 2010 demonstrate that prostate cancer can be detected by DWI due to its increased cell density and decreased diffusiveness, either qualitatively in DWI images or quantitatively by means of the apparent diffusion coefficient (ADC). In the prostate, the ADC is influenced by the strength of diffusion weighting, localization (peripheral or transitional zone), presence of prostatitis or hemorrhage and density and differentiation of prostate cancer cells. Mean differences between healthy tissue of the peripheral zone and prostate cancer appear to be smaller for ADC than for the (choline + creatine)/citrate ratio in MR spectroscopy. Test quality parameters vary greatly between different studies but appear to be slightly better for combined MRI and DWI than for MRI of the prostate alone. Clinical validation of DWI of the prostate requires both increased technical conformity and increased numbers of patients in clinical studies. (orig.) [de

  5. Diffusion-weighted MRI in cervical cancer

    International Nuclear Information System (INIS)

    McVeigh, Patrick Z.; Haider, Masoom A.; Syed, Aejaz M.; Milosevic, Michael; Fyles, Anthony

    2008-01-01

    The purpose was to investigate the potential value of apparent diffusion coefficient (ADC) measurement with MRI in the assessment of cervix cancer. Diffusion-weighted MRI was performed in 47 patients with cervical carcinoma undergoing chemoradiation therapy and 26 normal controls on a 1.5-T system with a b-value of 600 s/mm 2 . FIGO stage, tumor volume, nodal status, interstitial fluid pressure (IFP) and oxygen measurements were recorded. Response was defined as no visible tumor 3-6 months following completion of therapy. The average median ADC (mADC) of cervical carcinomas (1.09±0.20 x 10 -3 mm 2 /s) was significantly lower than normal cervix (2.09±0.46 x 10 -3 mm 2 /s) (P -3 mm 2 /s) compared to T2b (1.21 x 10 -3 mm 2 /s) and T3/T4 (1.10 x 10 -3 mm 2 /s) (P<0.001). In patients with squamous carcinomas the 90th percentile of ADC values was lower in responders than non-responders (P<0.05). Median ADC in cervix carcinoma is significantly lower compared to normal cervix. ADC may have predictive value in squamous tumors, but further long-term study will determine the ultimate clinical utility. (orig.)

  6. 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

  7. Diffusion-weighted MRI in acute cerebral stroke

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, Hideichi; Kobayashi, Masahito; Suga, Sadao; Kawase, Takeshi; Nagasawa, Masakazu; Sadanaga, Humiko; Okamura, Miyuki; Kanai, Yoshihiro; Mihara, Ban [Mihara Memorial Hospital, Isezaki, Gunma (Japan)

    1999-03-01

    Diffusion-weighted MRI has been demonstrated to be valuable in the assessment of cerebral stroke. Recent advance in MR systems of hardware with larger maximum gradient amplitude and faster imaging strategies, such as EPI, has made it possible to acquire whole brain diffusion-weighted imaging (DWI) in less that one minute. The purposes of this study are to evaluate clinical usefulness of DWI and to clarify pitfalls in the diagnosis of acute cerebral stroke. Seventeen patients with 18 ischemic lesions were studied. DWI were taken with 1.5 Tesla MRI (Magnetom Vision, Siemens, Germany) using EPI sequence. Fifteen lesions out of them (3 in cerebral cortex, 9 in basal ganglia/deep white matter and 3 in cerebellum) were studied serially at various times up to 147 days. Acute cerebral infarction was seen clearly as an area of hyperintensity with DWI and as hypointensity in apparent diffusion coefficient (ADC) maps which are indicative of decreased diffusion. DWI detected areas of hyperintense acute infarcts, as early as 2.5 hours after onset, which were not visualized on T{sub 2}-weighted image (T2WI). The lesion of cerebral infarction became isointense in ADC maps at 14-28 days after onset, whereas with DWI it became isointense at about 2 months. Because ADC changed earlier than DWI, ADC maps were useful for differentiate acute from nonacute lesion in cases of recurrent stroke within a short period. In a patient with transient global amnesia for 7 hours, DWI did not show any lesion at 8 hours. In terms of cerebral hemorrhage, lesions were seen as area of hyperintensity in DWI at 3 days and were not distinguishable from that of infarct. Despite limitations in the diagnosis of transient ischemia and cerebral hemorrhage, DWI is a useful technique for early detection of cerebral infarction, especially within the first 6 hours after stroke onset. (author)

  8. Diffusion-weighted MRI in acute cerebral stroke

    International Nuclear Information System (INIS)

    Takayama, Hideichi; Kobayashi, Masahito; Suga, Sadao; Kawase, Takeshi; Nagasawa, Masakazu; Sadanaga, Humiko; Okamura, Miyuki; Kanai, Yoshihiro; Mihara, Ban

    1999-01-01

    Diffusion-weighted MRI has been demonstrated to be valuable in the assessment of cerebral stroke. Recent advance in MR systems of hardware with larger maximum gradient amplitude and faster imaging strategies, such as EPI, has made it possible to acquire whole brain diffusion-weighted imaging (DWI) in less that one minute. The purposes of this study are to evaluate clinical usefulness of DWI and to clarify pitfalls in the diagnosis of acute cerebral stroke. Seventeen patients with 18 ischemic lesions were studied. DWI were taken with 1.5 Tesla MRI (Magnetom Vision, Siemens, Germany) using EPI sequence. Fifteen lesions out of them (3 in cerebral cortex, 9 in basal ganglia/deep white matter and 3 in cerebellum) were studied serially at various times up to 147 days. Acute cerebral infarction was seen clearly as an area of hyperintensity with DWI and as hypointensity in apparent diffusion coefficient (ADC) maps which are indicative of decreased diffusion. DWI detected areas of hyperintense acute infarcts, as early as 2.5 hours after onset, which were not visualized on T 2 -weighted image (T2WI). The lesion of cerebral infarction became isointense in ADC maps at 14-28 days after onset, whereas with DWI it became isointense at about 2 months. Because ADC changed earlier than DWI, ADC maps were useful for differentiate acute from nonacute lesion in cases of recurrent stroke within a short period. In a patient with transient global amnesia for 7 hours, DWI did not show any lesion at 8 hours. In terms of cerebral hemorrhage, lesions were seen as area of hyperintensity in DWI at 3 days and were not distinguishable from that of infarct. Despite limitations in the diagnosis of transient ischemia and cerebral hemorrhage, DWI is a useful technique for early detection of cerebral infarction, especially within the first 6 hours after stroke onset. (author)

  9. Subcentimeter hypervascular nodule with typical imaging findings of hepatocellular carcinoma in patients with history of hepatocellular carcinoma: natural course on serial gadoxetic acid-enhanced MRI and diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kyoung Doo; Kim, Seong Hyun; Lim, Hyo Keun [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Jung, Sin-Ho [Sungkyunkwan University School of Medicine, Center for Biostatistics and Clinical Epidemiology, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Samsung Advanced Institute for Health Sciences and Technology, Seoul (Korea, Republic of); Sohn, Insuk [Sungkyunkwan University School of Medicine, Center for Biostatistics and Clinical Epidemiology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Hyung Sik [Gachon Medical School, Department of Radiology, Gil Medical Center, Incheon (Korea, Republic of)

    2015-09-15

    To evaluate the natural course of subcentimeter hypervascular nodules at high risk for developing into hepatocellular carcinomas (SHNHR) using serial magnetic resonance imaging (MRI) in patients with a history of hepatocellular carcinoma (HCC). An SHNHR was defined as a subcentimeter hypervascular nodule having typical imaging findings of HCC on gadoxetic acid-enhanced MRI and diffusion-weighted imaging. We included 39 patients with 46 SHNHRs (mean size ± standard deviation, 6.1 ± 1.6 mm; range, 3.2 - 9.0 mm). Overt HCC was defined as pathology proven HCC or a nodule larger than 1 cm with typical imaging findings of HCC. The cumulative rate and the independent predictive factors for progression to overt HCC were evaluated. The median follow-up period was 139 days (range, 64 - 392 days). The cumulative progression rate to overt HCC at 3, 6, 9, and 12 months was 13.9 %, 61.7 %, 83.2 %, and 89.9 %. The initial size of SHNHR was a significant predictor of progression to overt HCC, with an optimal cut-off value of 5.5 mm. The progression rate of SHNHR to overt HCC within 12 months was high (89.9 %) in patients with history of HCC. The initial size of SHNHR was an important predictor for progression to overt HCC. (orig.)

  10. Diffusion-weighted MRI in acute posterior ischemic optic neuropathy

    International Nuclear Information System (INIS)

    Srinivasan, Sivasubramanian; Moorthy, Srikant; Sreekumar, KP; Kulkarni, Chinmay

    2012-01-01

    Blindness following surgery, especially cardiac surgery, has been reported sporadically, the most common cause being ischemic optic neuropathy. The role of MRI in the diagnosis of this condition is not well established. We present a case of postoperative posterior ischemic optic neuropathy that was diagnosed on diffusion-weighted MRI

  11. Serial diffusion-weighted imaging in a patient with MELAS and presumed cytotoxic oedema

    International Nuclear Information System (INIS)

    Wang, X.Y.; Noguchi, K.; Ogawa, S.; Seto, H.; Takashima, S.; Hayashi, N.

    2003-01-01

    A patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was studied with serial diffusion-weighted MRI (DWI) after stroke-like episodes and the apparent diffusion coefficient (ADC) was measured in an infarct-like lesion. In the acute and subacute stages, the affected area gave high signal on DWI and its ADC was much lower than that in a normal control region. In the chronic stage, the ADC became higher than that in normal brain. We therefore suggest that the stroke-like episodes did not cause vasogenic oedema but were related to energy failure and cytotoxic oedema. (orig.)

  12. Diffusion-weighted MRI in shaken baby syndrome

    International Nuclear Information System (INIS)

    Chan, Yu-Leung; Chu, Winnie C.W.; Wong, Gary W.K.; Yeung, David K.W.

    2003-01-01

    We present the characteristic CT and MRI findings of a 2-month-old girl with shaken baby syndrome. Diffusion-weighted MR imaging performed 8 days after the insult established the presence of injury to the white matter in the corpus callosum and subcortical white matter in the temporo-occipito-parietal region. Diffusion-weighted MR imaging is valuable in the diagnostic work-up of suspected shaken baby syndrome, as injury to the white matter can be demonstrated days after the injury. (orig.)

  13. Diffusion-weighted MRI of maple syrup urine disease encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Cavalleri, F.; Mavilla, L. [Servizio di Neuroradiologia, Azienda Ospedaliera Policlinico, Modena (Italy); Berardi, A.; Ferrari, F. [Servizio di Neonatologia, Azienda Ospedaliera Policlinico, Modena (Italy); Burlina, A.B. [Dipartimento di Pediatria, Azienda Ospedaliera, Universita di Padova, Padua (Italy)

    2002-06-01

    We report the case of a newborn child with maple syrup urine disease (MSUD), diagnosed at 10 days of life. Diffusion-weighted echoplanar MRI showed marked hyperintensity of the cerebellar white matter, the brainstem, the cerebral peduncles, the thalami, the dorsal limb of the internal capsule and the centrum semiovale, while conventional dual-echo sequence evidenced only a weak diffuse T2 hyperintensity in the cerebellar white matter and in the dorsal brainstem. The apparent diffusion coefficient (ADC) of these regions was markedly (>80%) decreased. Therefore, in agreement with current hypotheses on MSUD pathogenesis, MSUD oedema proves to be a cytotoxic oedema. Diffusion-weighted MRI may be a valuable tool, more sensitive than conventional spin-echo techniques, to assess the extent and progression of cytotoxicity in MSUD, as well as the effectiveness of the therapeutic interventions. (orig.)

  14. Diffusion-weighted MRI of maple syrup urine disease encephalopathy

    International Nuclear Information System (INIS)

    Cavalleri, F.; Mavilla, L.; Berardi, A.; Ferrari, F.; Burlina, A.B.

    2002-01-01

    We report the case of a newborn child with maple syrup urine disease (MSUD), diagnosed at 10 days of life. Diffusion-weighted echoplanar MRI showed marked hyperintensity of the cerebellar white matter, the brainstem, the cerebral peduncles, the thalami, the dorsal limb of the internal capsule and the centrum semiovale, while conventional dual-echo sequence evidenced only a weak diffuse T2 hyperintensity in the cerebellar white matter and in the dorsal brainstem. The apparent diffusion coefficient (ADC) of these regions was markedly (>80%) decreased. Therefore, in agreement with current hypotheses on MSUD pathogenesis, MSUD oedema proves to be a cytotoxic oedema. Diffusion-weighted MRI may be a valuable tool, more sensitive than conventional spin-echo techniques, to assess the extent and progression of cytotoxicity in MSUD, as well as the effectiveness of the therapeutic interventions. (orig.)

  15. Diffusion-weighted MRI of myelination in the rat brain following treatment with gonadal hormones

    International Nuclear Information System (INIS)

    Prayer, D.; Roberts, T.; Barkovich, A.J.; Prayer, L.; Kucharczyk, J.; Moseley, M.; Arieff, A.

    1997-01-01

    Previous studies have demonstrated the ability of high-resolution diffusion-weighted MRI to show maturation of white-matter structures in the developing rat brain. The purpose of this study was to investigate the influence of gonadal steroid hormones on the rate of this development. Starting from their second postnatal day, 16 rat-pups of either sex were repeatedly treated with subcutaneous implants containing 17-beta estradiol or delta-androstene 3,17 dione, respectively. Serial T1-, T2- and diffusion-weighted MRI was performed weekly for 8 weeks using a 4.7 T unit. Maturation of anterior optic pathways and hemisphere commissures was assessed. Diffusion-weighted images were processed to produce ''anisotropy index maps'', previously shown to be sensitive to white-matter maturation. Compared with untreated rat-pups, estrogen-treated animals showed accelerated, and testosterone-treated animals delayed maturation on anisotropy index maps and histological sections. In all animals, maturational changes appeared earlie on anisotropy index maps than on other MRI sequences or on myelin-sensitive stained sections. Diffusion-weighted imaging, and the construction of spatial maps sensitive to diffusion anisotropy, seem to be the most sensitive approach for the detection of maturational white-matter changes, and thus may hold potential for early diagnosis of temporary delay or permanent disturbances of white-matter development. (orig.). With 6 figs., 1 tab

  16. Diffusion-weighted MRI of myelination in the rat brain following treatment with gonadal hormones

    Energy Technology Data Exchange (ETDEWEB)

    Prayer, D. [Department of Radiology, Section of Neuroradiology, University of Vienna (Austria); Roberts, T. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Barkovich, A.J. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Prayer, L. [Department of Radiology, Section of Neuroradiology, University of Vienna (Austria); Kucharczyk, J. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Moseley, M. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Arieff, A. [Department of Medicine, Geriatrics Section, Veteran`s Affairs Medical Center and University of California at San Francisco (UCSF), CA (United States)

    1997-05-01

    Previous studies have demonstrated the ability of high-resolution diffusion-weighted MRI to show maturation of white-matter structures in the developing rat brain. The purpose of this study was to investigate the influence of gonadal steroid hormones on the rate of this development. Starting from their second postnatal day, 16 rat-pups of either sex were repeatedly treated with subcutaneous implants containing 17-beta estradiol or delta-androstene 3,17 dione, respectively. Serial T1-, T2- and diffusion-weighted MRI was performed weekly for 8 weeks using a 4.7 T unit. Maturation of anterior optic pathways and hemisphere commissures was assessed. Diffusion-weighted images were processed to produce ``anisotropy index maps``, previously shown to be sensitive to white-matter maturation. Compared with untreated rat-pups, estrogen-treated animals showed accelerated, and testosterone-treated animals delayed maturation on anisotropy index maps and histological sections. In all animals, maturational changes appeared earlie on anisotropy index maps than on other MRI sequences or on myelin-sensitive stained sections. Diffusion-weighted imaging, and the construction of spatial maps sensitive to diffusion anisotropy, seem to be the most sensitive approach for the detection of maturational white-matter changes, and thus may hold potential for early diagnosis of temporary delay or permanent disturbances of white-matter development. (orig.). With 6 figs., 1 tab.

  17. Diffusion-weighted MRI of adult male pelvic cancers

    International Nuclear Information System (INIS)

    Lim, K.S.; Tan, C.H.

    2012-01-01

    Magnetic resonance imaging (MRI), with its superior soft-tissue delineation, plays a pivotal role in the staging and surveillance of cancers affecting adult males, in particular, rectal, urinary bladder, and prostate cancers. There has been much recent interest in the complementary roles of diffusion-weighted imaging (DWI) for imaging of pelvic cancers. DWI measures the diffusivity of water molecules in biological tissue. Cancer, with its high cellular density and nuclear:cytoplasmic ratio, and extracellular disorganization, typically shows significant restricted diffusivity compared with surrounding normal tissue. In theory, diffusivity of water molecules may vary according to degree of tumour aggressiveness and changes in cell density and extracellular fluid content after treatment. Information regarding these variations may be used to study the histological grades of cancers and their response to treatment. In this article, we present the currently available evidence on the potential roles of DWI for the assessment of pelvic cancers in men, and demonstrate with imaging examples how this knowledge may be applied to daily clinical practice.

  18. Diffusion-weighted MRI of the transplanted liver

    International Nuclear Information System (INIS)

    Sandrasegaran, K.; Ramaswamy, R.; Ghosh, S.; Tahir, B.; Akisik, F.M.; Saxena, R.; Kwo, P.

    2011-01-01

    Aim: To assess the value of diffusion-weighted imaging (DWI) in evaluating parenchymal disorders following orthotopic liver transplantation (OLT). Materials and methods: This institutional review board-approved, retrospective study measured the hepatic apparent diffusion coefficients (ADC) in patients following OLT. Those with vascular complications or within 3 months of OLT were excluded. A single-shot echoplanar sequence with b values of 50, 400 (or 500), and 800 s/mm 2 was performed. Liver biopsy specimens [performed with a median of 17 days after magnetic resonance imaging (MRI)] were recorded for the presence and severity of parenchymal disorders, such as acute cellular rejection, and recurrence of fibrosis in all patients, and the recurrence of viral hepatitis in patients with hepatitis C. ADC values were measured blinded to histology in 41 patients (33 males) who had 56 MRI scans. Results: There was a significant difference in ADC values associated with a histological abnormality seen on core biopsy [n = 43, mean (SD) ADC of 0.91 (0.15)x10 -3 mm 2 /s] and those associated with no histological abnormality [n = 13, mean (SD) ADC of 1.11 (0.17)x10 -3 mm 2 /s; (p = 0.003)]. ADC values did not predict any of the individual parenchymal disorders on logistic regression analysis. When the ADC value was -3 mm 2 /s, there was a sensitivity and specificity of 85% and 72%, respectively, in predicting a parenchymal disorder (area under ROC curve = 0.84; 95% CI 0.72 to 0.92). Conclusion: ADC measurements may help in deciding which patients require core liver biopsy after OLT. However, ADC values are not likely to be reliable in differentiating between the various parenchymal disorders.

  19. Diffusion-weighted MRI of the transplanted liver

    Energy Technology Data Exchange (ETDEWEB)

    Sandrasegaran, K., E-mail: ksandras@iupui.edu [Department of Radiology, Indiana University School of Medicine, Indianapolis, IN (United States); Ramaswamy, R. [Department of Radiology, Indiana University School of Medicine, Indianapolis, IN (United States); Ghosh, S. [Department of Mathematics, Indiana University, IN (United States); Tahir, B.; Akisik, F.M. [Department of Radiology, Indiana University School of Medicine, Indianapolis, IN (United States); Saxena, R. [Department of Pathology, Indiana University School of Medicine, Indianapolis, IN (United States); Kwo, P. [Department of Medicine, Indiana University School of Medicine, Indianapolis, IN (United States)

    2011-09-15

    Aim: To assess the value of diffusion-weighted imaging (DWI) in evaluating parenchymal disorders following orthotopic liver transplantation (OLT). Materials and methods: This institutional review board-approved, retrospective study measured the hepatic apparent diffusion coefficients (ADC) in patients following OLT. Those with vascular complications or within 3 months of OLT were excluded. A single-shot echoplanar sequence with b values of 50, 400 (or 500), and 800 s/mm{sup 2} was performed. Liver biopsy specimens [performed with a median of 17 days after magnetic resonance imaging (MRI)] were recorded for the presence and severity of parenchymal disorders, such as acute cellular rejection, and recurrence of fibrosis in all patients, and the recurrence of viral hepatitis in patients with hepatitis C. ADC values were measured blinded to histology in 41 patients (33 males) who had 56 MRI scans. Results: There was a significant difference in ADC values associated with a histological abnormality seen on core biopsy [n = 43, mean (SD) ADC of 0.91 (0.15)x10{sup -3} mm{sup 2}/s] and those associated with no histological abnormality [n = 13, mean (SD) ADC of 1.11 (0.17)x10{sup -3} mm{sup 2}/s; (p = 0.003)]. ADC values did not predict any of the individual parenchymal disorders on logistic regression analysis. When the ADC value was <0.99x10{sup -3} mm{sup 2}/s, there was a sensitivity and specificity of 85% and 72%, respectively, in predicting a parenchymal disorder (area under ROC curve = 0.84; 95% CI 0.72 to 0.92). Conclusion: ADC measurements may help in deciding which patients require core liver biopsy after OLT. However, ADC values are not likely to be reliable in differentiating between the various parenchymal disorders.

  20. Transient detection of early wallerian degeneration on diffusion-weighted MRI after an acute cerebrovascular accident

    International Nuclear Information System (INIS)

    Uchino, A.; Sawada, A.; Takase, Y.; Egashira, R.; Kudo, S.

    2004-01-01

    We report three patients with a cerebrovascular accident studied serially by MRI, including diffusion-weighted imaging (DWI). In case 1, DWI 1 day after the onset of left frontoparietal cortical infarcts showed no abnormal signal in the left corticospinal tract. DWI 12 days after onset showed high signal in the corticospinal tract, interpreted as early wallerian degeneration. This had disappeared by 22 days after onset. In case 2, DWI obtained 7 days after the onset of a right internal capsule lacunar infarct showed high signal from the right corticospinal tract in the brainstem, which was less marked 15 days after onset. In case 3, MRI on postnatal day 7 showed a cerebral haemorrhage in the right corona radiata and high signal from the right corticospinal tract on DWI. The latter disappeared by day 23. DWI shows early wallerian degeneration; transient signal abnormalities within 2 weeks of stroke should not be mistaken for new ischaemic lesions. (orig.)

  1. Transient detection of early wallerian degeneration on diffusion-weighted MRI after an acute cerebrovascular accident

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Sawada, A.; Takase, Y.; Egashira, R.; Kudo, S. [Department of Radiology, Saga Medical School, 5-1-1 Nabeshima, Saga, 849-8501 (Japan)

    2004-03-01

    We report three patients with a cerebrovascular accident studied serially by MRI, including diffusion-weighted imaging (DWI). In case 1, DWI 1 day after the onset of left frontoparietal cortical infarcts showed no abnormal signal in the left corticospinal tract. DWI 12 days after onset showed high signal in the corticospinal tract, interpreted as early wallerian degeneration. This had disappeared by 22 days after onset. In case 2, DWI obtained 7 days after the onset of a right internal capsule lacunar infarct showed high signal from the right corticospinal tract in the brainstem, which was less marked 15 days after onset. In case 3, MRI on postnatal day 7 showed a cerebral haemorrhage in the right corona radiata and high signal from the right corticospinal tract on DWI. The latter disappeared by day 23. DWI shows early wallerian degeneration; transient signal abnormalities within 2 weeks of stroke should not be mistaken for new ischaemic lesions. (orig.)

  2. Atypical abdominal paediatric lymphangiomatosis: diagnosis aided by diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Humphries, Paul D.; Olsen, Oeystein E.; Wynne, Catherine S.; Sebire, Neil J.

    2006-01-01

    We report a 4-year-old child with a mesenteric mass, which on ultrasound, CT and conventional MRI appeared solid, raising lymphoma as a possible diagnosis. Diffusion weighted MRI (DW-MRI), however, suggested a low-cellularity lesion, making lymphoma less likely. Biopsy confirmed lymphangioma. DW-MRI may be a useful adjunct to conventional imaging, even in the abdomen. (orig.)

  3. Diffusion-weighted MRI in the diagnosis of intracranial hematomas

    OpenAIRE

    Şanlı, Davut; Ünal, Özkan; Bora, Aydın; Beyazal, Mehmet; Yavuz, Alpaslan; Avcu, Serhat

    2013-01-01

    Abstract. To determinate the diagnostic value of diffusion-weighted MR imaging (DWI) in intracerebral hematomas, epidural hematomas, subdural hematomas, and subarachnoid hemorrhage, and to assess the contribution of diffusion signal characteristics in the differentiation of hematoma stages. In this prospective study, consecutive 67 patients (range: 3-89 years), 35 (18 men 17 women) with intracerebral hematoma, 18 (10 men 8 women) with subdural hematoma, 2 (1 man 1 woman) with epidural hematom...

  4. Nonrigid Registration of Prostate Diffusion-Weighted MRI

    Directory of Open Access Journals (Sweden)

    Lei Hao

    2017-01-01

    Full Text Available Motion and deformation are common in prostate diffusion-weighted magnetic resonance imaging (DWI during acquisition. These misalignments lead to errors in estimating an apparent diffusion coefficient (ADC map fitted with DWI. To address this problem, we propose an image registration algorithm to align the prostate DWI and improve ADC map. First, we apply affine transformation to DWI to correct intraslice motions. Then, nonrigid registration based on free-form deformation (FFD is used to compensate for intraimage deformations. To evaluate the influence of the proposed algorithm on ADC values, we perform statistical experiments in three schemes: no processing of the DWI, with the affine transform approach, and with FFD. The experimental results show that our proposed algorithm can correct the misalignment of prostate DWI and decrease the artifacts of ROI in the ADC maps. These ADC maps thus obtain sharper contours of lesions, which are helpful for improving the diagnosis and clinical staging of prostate cancer.

  5. Diffusion-weighted MRI for uveal melanoma liver metastasis detection

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Mathilde; Petras, Slavomir; Servois, Vincent [Institut Curie, Department of Radiology and Nuclear Medicine, Paris (France); Mariani, Pascale; Cassoux, Nathalie [Institut Curie, Department of Surgery, Paris (France); Bidard, Francois Clement; Rodrigues, Manuel Jorge; Piperno-Neumann, Sophie [Institut Curie, Department of Medical Oncology, Paris (France); Farkhondeh, Fereshteh [Institut Curie, Department of Pathology, Paris (France)

    2015-08-15

    We aimed to assess the sensitivity of diffusion-weighted (DW) magnetic resonance (MR) imaging for the detection of pathologically confirmed uveal melanoma liver metastases (UMLM). Twenty patients who underwent complete surgical resection of their UMLM (N = 83) were included. Pre-surgery liver MR imaging included T2-weighted, T1-weighted, DW and dynamic-gadolinium-enhanced MR sequences. Two radiologists independently reviewed three sets of images (DW / morphologic-dynamic / combined) for each patient using intraoperative and pathological findings as a standard of reference. The sensitivities of the morphologic-dynamic and DW images for UMLM detection were 63 % and 59 %, respectively, for reader 1 (R1) and 64 % and 53 %, for reader 2 (R2). Sensitivity of the combined set was higher than sensitivity in the two other sets (R1:69 %, R2:67 %), but was only significantly different than the sensitivity of the DW images (McNemar test). For the three sets and the two readers, the sensitivity for UMLM smaller than 5 mm (37-46 %) was significantly lower than that for UMLM larger than 5 mm (67-90 %). The sensitivity for UMLM located in the subcapsular area (41-54 %) was significantly lower than that for intraparenchymal UMLM (68-86 %) (Chi-square test). Our study shows that the addition of DW imaging to morphologic-dynamic images does not significantly increase MR sensitivities for UMLM detection. (orig.)

  6. Diffusion-weighted echo-planar MRI of lacunar infarcts

    International Nuclear Information System (INIS)

    Noguchi, K.; Nagayoshi, T.; Watanabe, N.; Kanazawa, T.; Toyoshima, S.; Morijiri, M.; Shojaku, H.; Shimizu, M.; Seto, H.

    1998-01-01

    We studied 35 patients with lacunar infarcts, using diffusion-weighted echo-planar imaging (DW-EPI) at 1.5 T. The relative apparent diffusion coefficient ratio (ADCR) of each lesion was calculated and lesion conspicuity on DW-EPI was compared to that on images aquired with fast fluid-attenuated inversion recovery and T2-weighted fast spin-echo sequences. Acute small infarcts (within 3 days) were identified with DW-EPI as an area of decreased ADCR (range 0.33-0.87; mean 0.67) and high signal, subacute small infarcts (4-30 days) as a high-signal or isointense areas of decreased or nearly normal ADCR (0.54-0.98; 0.73), and chronic small infarcts (> 30 days) as low- or high-signal areas of nearly normal or increased ADCR (0.97-1.92; 1.32). In three patients, small infarcts of the brain stem in the hyperacute phase (within 6 h) were seen only with DW-EPI. In five patients, fresh small infarcts adjacent to multiple old infarcts could be distinguished only with DW-EPI. (orig.)

  7. Elastography and diffusion-weighted MRI in patients with rectal cancer

    DEFF Research Database (Denmark)

    Rafaelsen, Søren Rafael; Vagn-Hansen, Chris Aksel; Sørensen, Torben

    2015-01-01

    -weighted coefficient (ADC). The purpose of the present study was to compare quantitative elastography based on ultrasound shear wave measurements with MRI ADC. METHODS: We prospectively examined 52 patients with histopathologically proven rectal cancer. The mean age was 67 years (range 42-90 years). Males: 39, females...... a correlation between tissue elasticity and diffusion in rectal cancer.......OBJECTIVE: The current literature has described the usefulness of elastography and diffusion-weighted MRI in patients with cancer, but to the best of our knowledge so far none of them has compared the two new methods. The tumour cell density is related to the MRI-measured apparent diffusion...

  8. Conventional and Diffusion-Weighted MRI in the Evaluation of Methanol Poisoning. A case report

    International Nuclear Information System (INIS)

    Server, A.; Nakstad, P.Hj.; Dullerud, R.; Haakonsen, M.; Hovda, K.E.; Jacobsen, D.

    2003-01-01

    Cerebral lesions were studied in 2 methanol-poisoned patients using conventional magnetic resonance imaging (MRI). In 1 patient, diffusion-weighted MRI (DWI) was also performed. In this patient, conventional MRI showed symmetrical, bilateral increased signal in the lentiform nuclei, involving predominantly putamina, but also extending into the corona radiata, centrum semiovale and subcortical white matter. DWI showed decreased diffusion, which most probably reflects cytotoxic edema. In the other patient, fluid attenuated-inversion recovery (FLAIR) and T2-weighted images showed hyperintensity in the putamina, characteristic of post-necrotic changes

  9. Diffusion-weighted MRI and quantitative biophysical modeling of hippocampal neurite loss in chronic stress.

    Directory of Open Access Journals (Sweden)

    Peter Vestergaard-Poulsen

    Full Text Available Chronic stress has detrimental effects on physiology, learning and memory and is involved in the development of anxiety and depressive disorders. Besides changes in synaptic formation and neurogenesis, chronic stress also induces dendritic remodeling in the hippocampus, amygdala and the prefrontal cortex. Investigations of dendritic remodeling during development and treatment of stress are currently limited by the invasive nature of histological and stereological methods. Here we show that high field diffusion-weighted MRI combined with quantitative biophysical modeling of the hippocampal dendritic loss in 21 day restraint stressed rats highly correlates with former histological findings. Our study strongly indicates that diffusion-weighted MRI is sensitive to regional dendritic loss and thus a promising candidate for non-invasive studies of dendritic plasticity in chronic stress and stress-related disorders.

  10. Diffusion-weighted MRI in Crohn's disease: Current status and recommendations

    OpenAIRE

    Dohan, A.; Taylor, S.; Hoeffel, C.; Barret, M.; Allez, M.; Dautry, R.; Zappa, M.; Savoye-Collet, C.; Dray, X.; Boudiaf, M.; Reinhold, C.; Soyer, P.

    2016-01-01

    Over the past years, technological improvements and refinements in magnetic resonance imaging (MRI) hardware have made high-quality diffusion-weighted imaging (DWI) routinely possible for the bowel. DWI is promising for the detection and characterization of lesions in Crohn's disease (CD) and has been advocated as an alternative to intravenous gadolinium-based contrast agents. Furthermore, quantification using the apparent diffusion coefficient may have value as a biomarker of CD activity and...

  11. Diffusion-weighted MRI of lymphoma: prognostic utility and implications for PET/MRI?

    Energy Technology Data Exchange (ETDEWEB)

    Punwani, Shonit; Taylor, Stuart A.; Halligan, Steve [University College London, Centre for Medical Imaging, London (United Kingdom); University College London Hospital, Department of Radiology, London (United Kingdom); Saad, Ziauddin Z.; Groves, Ashley [University College London Hospital, Institute of Nuclear Medicine, London (United Kingdom); Bainbridge, Alan [University College London Hospital, Department of Medical Physics and Bioengineering, London (United Kingdom); Daw, Stephen; Shankar, Ananth [University College London Hospital, Department of Paediatrics, London (United Kingdom); Humphries, Paul D. [University College London Hospital, Department of Radiology, London (United Kingdom); Great Ormond Street Hospital, Department of Radiology, London (United Kingdom)

    2013-03-15

    With the recent introduction of PET/MRI, we investigated whether diffusion-weighted imaging (DWI) can complement PET for predicting local treatment response in Hodgkin lymphoma. This retrospective study included 39 patients selected from a hospital database with a histological diagnosis of Hodgkin lymphoma undergoing whole-body MRI (supplemented by DWI) and PET/CT before and after two cycles of vincristine, etoposide, prednisolone and doxorubicin (OEPA). The pretreatment volume, MRI apparent diffusion coefficient (ADC) and PET maximum standardized uptake value (SUV{sub max}) of the largest nodal mass were determined quantitatively for evaluation of the local response following two cycles of OEPA. Quantitative pretreatment imaging biomarkers (disease volume, ADC, SUV{sub max}) were compared between sites with an adequate and those with an inadequate response using Fisher's exact test and Mann Whitney statistics. Multivariate models predictive of an inadequate response based on demographic/clinical features, pretreatment disease volume and SUV{sub max} without (model 1) and with (model 2) the addition of ADC were derived and crossvalidated. The ROC area under curve (AUC) was calculated for both models using the full dataset (training) and the crossvalidation (test) data. Sites with an adequate response had a significantly lower median pretreatment ADC (1.0 x 10{sup -3}mm{sup 2}s{sup -1}) than those with an inadequate response (1.26 x 10{sup -3}mm{sup 2}s{sup -1}; p < 0.01). There were no significant differences in patient demographic/clinical parameters, pretreatment SUV{sub max} or pretreatment nodal volume between sites with inadequate and adequate response. The ROC-AUCs for prediction of an inadequate response for the training and test data for model 1 were 0.90 and 0.53, and for model 2 were 0.84 and 0.71, respectively. DWI complements PET for prediction of site-specific interim response to chemotherapy. (orig.)

  12. Diffusion-weighted MRI of the liver—Interpretative pearls and pitfalls

    International Nuclear Information System (INIS)

    Culverwell, A.D.; Sheridan, M.B.; Guthrie, J.A.; Scarsbrook, A.F.

    2013-01-01

    Diffusion-weighted magnetic resonance imaging (DW MRI) is an established technique in neuroradiology and more recently has emerged as a useful adjunct to various oncological applications of MRI. It has an expanding role in the evaluation of liver lesions, offers higher detection rates for small lesions, and can increase confidence in differentiating between benign and malignant lesions. Other applications include assessment of tumour response to therapy, differentiating tumour from bland thrombus, and assessment of liver fibrosis. DW sequences can be performed on most modern MRI machines with relative ease, in a short time period and without the need for contrast medium. DW MRI can be of value in the detection and characterization of hepatic lesions but there are pitfalls, which can potentially cause interpretative difficulty. This article will review the rationale for DW MRI in liver imaging, demonstrate the clinical utility of the technique in a spectrum of hepatic diseases, and illustrate key interpretative pearls and pitfalls

  13. Diffusion weighted MRI in intrahepatic bile duct adenoma arising from the cirrhotic liver

    Energy Technology Data Exchange (ETDEWEB)

    An, Chansik [Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Park, Sumi; Choi, Yoon Jung [National Health Insurance Corporation Ilsan Hospital, Goyang (Korea, Republic of)

    2013-10-15

    A 64-year-old male patient with liver cirrhosis underwent a CT study for hepatocellular carcinoma surveillance, which demonstrated a 1.4-cm hypervascular subcapsular tumor in the liver. On gadoxetic acid-enhanced MRI, the tumor showed brisk arterial enhancement and persistent hyperenhancement in the portal phase, but hypointensity in the hepatobiliary phase. On diffusion-weighted MRI, the tumor showed an apparent diffusion coefficient twofold greater than that of the background liver parenchyma, which suggested that the lesion was benign. The histologic diagnosis was intrahepatic bile duct adenoma with alcoholic liver cirrhosis.

  14. Diffusion-weighted MRI in intrahepatic bile duct adenoma arising from the cirrhotic liver.

    Science.gov (United States)

    An, Chansik; Park, Sumi; Choi, Yoon Jung

    2013-01-01

    A 64-year-old male patient with liver cirrhosis underwent a CT study for hepatocellular carcinoma surveillance, which demonstrated a 1.4-cm hypervascular subcapsular tumor in the liver. On gadoxetic acid-enhanced MRI, the tumor showed brisk arterial enhancement and persistent hyperenhancement in the portal phase, but hypointensity in the hepatobiliary phase. On diffusion-weighted MRI, the tumor showed an apparent diffusion coefficient twofold greater than that of the background liver parenchyma, which suggested that the lesion was benign. The histologic diagnosis was intrahepatic bile duct adenoma with alcoholic liver cirrhosis.

  15. Diffusion Weighted MRI as a predictive tool for effect of radiotherapy in locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Haack, Søren; Tanderup, Kari; Fokdal, Lars

    Diffusion weighted MRI has shown great potential in diagnostic cancer imaging and may also have value for monitoring tumor response during radiotherapy. Patients with advanced cervical cancer are treated with external beam radiotherapy followed by brachytherapy. This study evaluates the value of DW......-MRI for predicting outcome of patients with advanced cervical cancer at time of brachytherapy. Volume of hyper-intensity on highly diffusion sensitive images and resulting ADC value for treatment responders and non-responders is compared. The change of ADC and volume of hyper-intensity over time of BT is also...

  16. Associations among q-space MRI, diffusion-weighted MRI and histopathological parameters in meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Fatima, Zareen; Motosugi, Utaroh; Ishigame, Keiichi; Araki, Tsutomu [University of Yamanashi, Department of Radiology, Chuo-shi, Yamanashi (Japan); Waqar, Ahmed Bilal [University of Yamanashi, Department of Molecular Pathology, Interdisciplinary Graduate School of Medicine and Engineering, Chuo-shi, Yamanashi (Japan); Hori, Masaaki [Juntendo University, Department of Radiology, School of Medicine, Tokyo (Japan); Oishi, Naoki; Katoh, Ryohei [University of Yamanashi, Department of Pathology, Chuo-shi, Yamanashi (Japan); Onodera, Toshiyuki; Yagi, Kazuo [Tokyo Metropolitan University, Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo (Japan)

    2013-08-15

    The purposes of this MR-based study were to calculate q-space imaging (QSI)-derived mean displacement (MDP) in meningiomas, to evaluate the correlation of MDP values with apparent diffusion coefficient (ADC) and to investigate the relationships among these diffusion parameters, tumour cell count (TCC) and MIB-1 labelling index (LI). MRI, including QSI and conventional diffusion-weighted imaging (DWI), was performed in 44 meningioma patients (52 lesions). ADC and MDP maps were acquired from post-processing of the data. Quantitative analyses of these maps were performed by applying regions of interest. Pearson correlation coefficients were calculated for ADC and MDP in all lesions and for ADC and TCC, MDP and TCC, ADC and MIB-1 LI, and MDP and MIB-1 LI in 17 patients who underwent subsequent surgery. ADC and MDP values were found to have a strong correlation: r = 0.78 (P = <0.0001). Both ADC and MDP values had a significant negative association with TCC: r = -0.53 (p = 0.02) and -0.48 (P = 0.04), respectively. MIB-1 LI was not, however, found to have a significant association with these diffusion parameters. In meningiomas, both ADC and MDP may be representative of cell density. (orig.)

  17. Associations among q-space MRI, diffusion-weighted MRI and histopathological parameters in meningiomas

    International Nuclear Information System (INIS)

    Fatima, Zareen; Motosugi, Utaroh; Ishigame, Keiichi; Araki, Tsutomu; Waqar, Ahmed Bilal; Hori, Masaaki; Oishi, Naoki; Katoh, Ryohei; Onodera, Toshiyuki; Yagi, Kazuo

    2013-01-01

    The purposes of this MR-based study were to calculate q-space imaging (QSI)-derived mean displacement (MDP) in meningiomas, to evaluate the correlation of MDP values with apparent diffusion coefficient (ADC) and to investigate the relationships among these diffusion parameters, tumour cell count (TCC) and MIB-1 labelling index (LI). MRI, including QSI and conventional diffusion-weighted imaging (DWI), was performed in 44 meningioma patients (52 lesions). ADC and MDP maps were acquired from post-processing of the data. Quantitative analyses of these maps were performed by applying regions of interest. Pearson correlation coefficients were calculated for ADC and MDP in all lesions and for ADC and TCC, MDP and TCC, ADC and MIB-1 LI, and MDP and MIB-1 LI in 17 patients who underwent subsequent surgery. ADC and MDP values were found to have a strong correlation: r = 0.78 (P = <0.0001). Both ADC and MDP values had a significant negative association with TCC: r = -0.53 (p = 0.02) and -0.48 (P = 0.04), respectively. MIB-1 LI was not, however, found to have a significant association with these diffusion parameters. In meningiomas, both ADC and MDP may be representative of cell density. (orig.)

  18. Report of diffusion-weighted MRI in two cases with different cerebral hydatid disease

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-02-01

    To present MRI findings in two cases of cerebral hydatid disease with an emphasis on diffusion-weighted imaging (DWI) findings of Echinococcus granulosus (EG) versus Echinococcus alveolaris (EA). EG lesions were isointense with cerebrospinal fluid in all sequences including DWI. On DWI, EA lesions remained hypointense on b = 1000 s/mm2 diffusion-weighted images. Apparent diffusion coefficient (ADC) values of EG and EA lesions were completely different from each other, 2.88 {+-} 0.24 x 10{sup -3} s/mm{sup 2} and 1.33 {+-} 0.15 x 10{sup -3} s/mm{sup 2}, respectively. The ADC values could not be used to discriminate from other differential diagnoses.

  19. Report of diffusion-weighted MRI in two cases with different cerebral hydatid disease

    International Nuclear Information System (INIS)

    Kitis, O.; Calli, C.; Yunten, N.

    2004-01-01

    To present MRI findings in two cases of cerebral hydatid disease with an emphasis on diffusion-weighted imaging (DWI) findings of Echinococcus granulosus (EG) versus Echinococcus alveolaris (EA). EG lesions were isointense with cerebrospinal fluid in all sequences including DWI. On DWI, EA lesions remained hypointense on b = 1000 s/mm2 diffusion-weighted images. Apparent diffusion coefficient (ADC) values of EG and EA lesions were completely different from each other, 2.88 ± 0.24 x 10 -3 s/mm 2 and 1.33 ± 0.15 x 10 -3 s/mm 2 , respectively. The ADC values could not be used to discriminate from other differential diagnoses

  20. Comparison of diffusion-weighted fMRI and BOLD fMRI responses in a verbal working memory task

    International Nuclear Information System (INIS)

    Aso, Toshihiko; Urayama, Shin-ichi; Fukuyama, Hidenao; Le Bihan, Denis

    2013-01-01

    Diffusion-weighted functional MRI (DfMRI) has been reported to have a different response pattern in the visual cortex than that of BOLD-fMRI. Especially, the DfMRI signal shows a constantly faster response at both onset and offset of the stimulus, suggesting that the DfMRI signal might be more directly linked to neuronal events than the hemodynamic response. However, because the DfMRI response also contains a residual sensitivity to BOLD this hypothesis has been challenged. Using a verbal working memory task we show that the DfMRI time-course features are preserved outside visual cortices, but also less liable to between-subject/between-regional variation than the BOLD response. The overall findings not only support the feasibility of DfMRI as an approach for functional brain imaging, but also strengthen the uniqueness of the DfMRI signal origin. (authors)

  1. Diffusion weighted MRI by spatiotemporal encoding: Analytical description and in vivo validations

    Science.gov (United States)

    Solomon, Eddy; Shemesh, Noam; Frydman, Lucio

    2013-07-01

    Diffusion-weighted (DW) MRI is a powerful modality for studying microstructure in normal and pathological tissues. The accuracy derived from DW MRI depends on the acquisition of quality images, and on a precise assessment of the b-values involved. Conventional DW MRI tends to be of limited use in regions suffering from large magnetic field or chemical shift heterogeneities, which severely distort the MR images. In this study we propose novel sequences based on SPatio-temporal ENcoding (SPEN), which overcome such shortcomings owing to SPEN's inherent robustness to offsets. SPEN, however, relies on the simultaneous application of gradients and radiofrequency-swept pulses, which may impart different diffusion weightings along the spatial axes. These will be further complicated in DW measurements by the diffusion-sensitizing gradients, and will in general lead to complex, spatially-dependent b-values. This study presents a formalism for analyzing these diffusion-weighted SPEN (dSPEN) data, which takes into account the concomitant effects of adiabatic pulses, of the imaging as well as diffusion gradients, and of the cross-terms between them. These analytical b-values derivations are subject to experimental validations in phantom systems and ex vivo spinal cords. Excellent agreement is found between the theoretical predictions and these dSPEN experiments. The ensuing methodology is then demonstrated by in vivo mapping of diffusion in human breast - organs where conventional k-space DW acquisition methods are challenged by both field and chemical shift heterogeneities. These studies demonstrate the increased robustness of dSPEN vis-à-vis comparable DW echo planar imaging, and demonstrate the value of this new methodology for medium- or high-field diffusion measurements in heterogeneous systems.

  2. 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.)

  3. Detection of electroporation-induced membrane permeabilization states in the brain using diffusion-weighted MRI

    DEFF Research Database (Denmark)

    Mahmood, Faisal; Hansen, Rasmus H; Agerholm-Larsen, Birgit

    2015-01-01

    BACKGROUND: Tissue permeabilization by electroporation (EP) is a promising technique to treat certain cancers. Non-invasive methods for verification of induced permeabilization are important, especially in deep-seated cancers. In this study we evaluated diffusion-weighted magnetic resonance imaging...... (NP), transient membrane permeabilization (TMP), and permanent membrane permeabilization (PMP), respectively. DW-MRI was acquired 5 minutes, 2 hours, 24 hours and 48 hours after EP. Histology was performed for validation of the permeabilization states. Tissue content of water, Na+, K+, Ca2...... minutes after EP, compared to NP. Kurtosis was also significantly higher at 24 hours (pstates, supporting the DW-MRI findings. We conclude that DW-MRI is capable of detecting EP...

  4. Changes on diffusion-weighted MRI with focal motor status epilepticus: case report

    International Nuclear Information System (INIS)

    Loevblad, K.O.; Senn, P.; Zutter, D.; Bassetti, C.; Donati, F.; Loevblad, K.O.; Zeller, O.; Schroth, G.

    2003-01-01

    Transient imaging abnormalities, including changes on diffusion-weighted imaging (DWI), may be seen in focal status epilepticus. The changes on DWI provide an insight into the pathophysiology. We report a 53-year-old man with focal motor status epilepticus involving the left hand, arm and face with focal slowing on EEG. The apparent diffusion coefficients (ADC) were higher in the affected hemisphere than on the other side. At 10 days and 6 weeks after the end of the seizures, we saw normal ADCs and atrophy of the affected hemisphere. We conclude that the MRI findings indicate both cytotoxic and vasogenic oedema during seizure activity and subsequent loss of brain parenchyma. (orig.)

  5. Changes on diffusion-weighted MRI with focal motor status epilepticus: case report

    Energy Technology Data Exchange (ETDEWEB)

    Loevblad, K O [Neuroradiology, Radiodiagnostic, Hopital Cantonal de Geneve HUG, Geneve (Switzerland); Senn, P; Zutter, D; Bassetti, C; Donati, F [Dept. of Neurology, Inselspital, Univ. Hospital, Berne (Switzerland); Loevblad, K O; Zeller, O; Schroth, G [Div. of Neuroradiology, Inselspital, Univ. Hospital, Berne (Switzerland)

    2003-04-01

    Transient imaging abnormalities, including changes on diffusion-weighted imaging (DWI), may be seen in focal status epilepticus. The changes on DWI provide an insight into the pathophysiology. We report a 53-year-old man with focal motor status epilepticus involving the left hand, arm and face with focal slowing on EEG. The apparent diffusion coefficients (ADC) were higher in the affected hemisphere than on the other side. At 10 days and 6 weeks after the end of the seizures, we saw normal ADCs and atrophy of the affected hemisphere. We conclude that the MRI findings indicate both cytotoxic and vasogenic oedema during seizure activity and subsequent loss of brain parenchyma. (orig.)

  6. Pseudotumours in chronic kidney disease: Can diffusion-weighted MRI rule out malignancy

    International Nuclear Information System (INIS)

    Goyal, Ankur; Sharma, Raju; Bhalla, Ashu S.; Gamanagatti, Shivanand; Seth, Amlesh

    2013-01-01

    Highlights: •Conventional non-contrast MRI is unable to distinguish CKD pseudotumors from RCCs. •Pseudotumours in a background of CKD do not show restricted diffusion. •CKD pseudotumours demonstrate high ADC values whereas RCCs show restricted diffusion. •DW-MRI is reliable in ruling out malignancy incase of pseudotumours found in chronic kidney disease. •DW-MRI may obviate contrast administration and/or tissue sampling in renal pseudotumours and prevent inadvertent surgeries. -- Abstract: Objectives: To evaluate whether diffusion-weighted MRI (DW-MRI) can distinguish pseudotumours in chronic kidney disease (CKD pseudotumours) from renal-cell-carcinomas (RCCs) (with or without CKD) and whether it offers additional benefit over conventional MRI. Methods: One-hundred patients underwent MDCT, MRI and DW-MRI (at b-values of 0 and 500 s/mm 2 ) for evaluation of focal renal lesions. Of these, 20 patients with 40 CKD pseudotumours and 36 patients with 40 RCCs were retrospectively analyzed. T1-weighted, T2-weighted, diffusion-weighted images were evaluated, apparent-diffusion-coefficient (ADC) values were compared and receiver-operating-characteristic (ROC) curves were drawn to establish cut-off ADC-values. Results: 92.5% of CKD pseudotumours remained indeterminate after conventional MRI. On DW-MRI, none of them showed restricted diffusion and thus malignancy could be ruled out in 100% of the lesions. In contrast, all the solid RCCs showed diffusion restriction. Mean ADC-value for CKD pseudotumours was significantly higher than RCCs and surrounding diseased parenchyma [2.50 vs 1.56 (×10 −3 mm 2 /s) (P < 0.0001) and 2.05 (×10 −3 mm 2 /s) (P = 0.0001) respectively]. ROC analysis for differentiating CKD pseudotumours and RCC yielded high sensitivity (91.7%) and specificity (100%) for cut-off ADC-value of 2.04 (×10 −3 mm 2 /s). Conclusions: CKD pseudotumors usually remain indeterminate on conventional non-contrast MRI. DW-MRI can distinguish CKD pseudotumors

  7. Pseudotumours in chronic kidney disease: Can diffusion-weighted MRI rule out malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Ankur, E-mail: ankurgoyalaiims@gmail.com [Department of Radiodiagnosis, All India Institute of Medical Sciences (A.I.I.M.S.), New Delhi (India); Sharma, Raju, E-mail: raju152@yahoo.com [Department of Radiodiagnosis, All India Institute of Medical Sciences (A.I.I.M.S.), New Delhi (India); Bhalla, Ashu S., E-mail: ashubhalla1@yahoo.com [Department of Radiodiagnosis, All India Institute of Medical Sciences (A.I.I.M.S.), New Delhi (India); Gamanagatti, Shivanand, E-mail: shiv223@rediffmail.com [Department of Radiodiagnosis, All India Institute of Medical Sciences (A.I.I.M.S.), New Delhi (India); Seth, Amlesh, E-mail: amlesh.seth@gmail.com [Department of Urology, All India Institute of Medical Sciences (A.I.I.M.S.), New Delhi (India)

    2013-11-01

    Highlights: •Conventional non-contrast MRI is unable to distinguish CKD pseudotumors from RCCs. •Pseudotumours in a background of CKD do not show restricted diffusion. •CKD pseudotumours demonstrate high ADC values whereas RCCs show restricted diffusion. •DW-MRI is reliable in ruling out malignancy incase of pseudotumours found in chronic kidney disease. •DW-MRI may obviate contrast administration and/or tissue sampling in renal pseudotumours and prevent inadvertent surgeries. -- Abstract: Objectives: To evaluate whether diffusion-weighted MRI (DW-MRI) can distinguish pseudotumours in chronic kidney disease (CKD pseudotumours) from renal-cell-carcinomas (RCCs) (with or without CKD) and whether it offers additional benefit over conventional MRI. Methods: One-hundred patients underwent MDCT, MRI and DW-MRI (at b-values of 0 and 500 s/mm{sup 2}) for evaluation of focal renal lesions. Of these, 20 patients with 40 CKD pseudotumours and 36 patients with 40 RCCs were retrospectively analyzed. T1-weighted, T2-weighted, diffusion-weighted images were evaluated, apparent-diffusion-coefficient (ADC) values were compared and receiver-operating-characteristic (ROC) curves were drawn to establish cut-off ADC-values. Results: 92.5% of CKD pseudotumours remained indeterminate after conventional MRI. On DW-MRI, none of them showed restricted diffusion and thus malignancy could be ruled out in 100% of the lesions. In contrast, all the solid RCCs showed diffusion restriction. Mean ADC-value for CKD pseudotumours was significantly higher than RCCs and surrounding diseased parenchyma [2.50 vs 1.56 (×10{sup −3} mm{sup 2}/s) (P < 0.0001) and 2.05 (×10{sup −3} mm{sup 2}/s) (P = 0.0001) respectively]. ROC analysis for differentiating CKD pseudotumours and RCC yielded high sensitivity (91.7%) and specificity (100%) for cut-off ADC-value of 2.04 (×10{sup −3} mm{sup 2}/s). Conclusions: CKD pseudotumors usually remain indeterminate on conventional non-contrast MRI. DW-MRI

  8. Selection for biopsy of kidney transplant patients by diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Steiger, Philipp; Barbieri, Sebastiano; Ith, Michael; Thoeny, Harriet C. [Inselspital, Bern University Hospital, University of Bern, Inselspital, Department of Radiology, Neuroradiology, and Nuclear Medicine, Institute of Diagnostic, Pediatric, and Interventional Radiology, Bern (Switzerland); Kruse, Anja [Inselspital, Bern University Hospital, University of Bern, Inselspital, Department of Nephrology and Hypertension, Bern (Switzerland)

    2017-10-15

    To assess retrospectively whether diffusion-weighted magnetic resonance imaging (DW-MRI) allows physicians to determine the severity of histopathologic findings in biopsies of renal allograft patients with deteriorating renal function. Forty consecutive kidney transplant patients underwent DW-MRI and biopsy. Patients were assigned to one group with severe and to another group with normal or mild histopathologic findings. These two groups were compared based on a qualitative DW-MRI assessment (homo-/heterogeneity) and the combination of qualitative and quantitative DW-MRI parameters (ADC, and intravoxel incoherent motion, IVIM, parameters: D, f, D*). Sensitivity, specificity, and accuracy were determined for each parameter. Biopsy findings were severe in 25 patients and normal or mild in 15 patients. Qualitative DW-MRI led to a sensitivity of 44.0% and a specificity of 93.3%. Combined qualitative and quantitative DW-MRI led to an accuracy of 80% for both the minimal ADC (ADCmin) and the minimal perfusion fraction (fmin) with a sensitivity of 84.0% and 92.0% and a specificity of 73.3% and 60.0%, respectively. Combined qualitative and quantitative DW-MRI might allow physicians to determine the severity of histopathologic findings in biopsies of a high number of kidney transplant patients. (orig.)

  9. 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.)

  10. 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.)

  11. 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

  12. Evaluation of conventional, dynamic contrast enhanced and diffusion weighted MRI for quantitative Crohn's disease assessment with histopathology of surgical specimens

    NARCIS (Netherlands)

    Tielbeek, Jeroen A. W.; Ziech, Manon L. W.; Li, Zhang; Lavini, Cristina; Bipat, Shandra; Bemelman, Willem A.; Roelofs, Joris J. T. H.; Ponsioen, Cyriel Y.; Vos, Frans M.; Stoker, Jaap

    2014-01-01

    To prospectively compare conventional MRI sequences, dynamic contrast enhanced (DCE) MRI and diffusion weighted imaging (DWI) with histopathology of surgical specimens in Crohn's disease. 3-T MR enterography was performed in consecutive Crohn's disease patients scheduled for surgery within 4 weeks.

  13. 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

  14. 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.)

  15. Usefulness of diffusion-weighted MRI in differentiating benign from malignant musculoskeletal tumors

    International Nuclear Information System (INIS)

    Nagata, Shuji; Uchida, Masafumi; Hayabuchi, Naofumi

    2005-01-01

    The purpose of this study was to evaluate the usefulness of diffusion-weighted MRI in distinguishing different components and in differentiating benign from malignant musculoskeletal tumors. Fifty-seven patients with musculoskeletal tumors underwent MR at our institution from October 1999 to April 2002. We evaluated 57 tumors (9 bone tumors and 48 soft tissue tumors). All tumors were classified into 8 groups (myxomatous, fibrous, cystic, cartilaginous, fatty components, hematomas, other benign tumors, and other malignant tumors). MR examinations were performed with a 1.5-Tesla system. Diffusion-weighted single-shot echo planer imaging (EPI) images were obtained in all patients. Apparent diffusion coefficients (ADCs) were calculated by using b factors of 0 and 1,000 sec/mm 2 . ADC values of myxomatous, cystic, and cartilaginous components were significantly higher than those of other tumors. In cartilaginous tumors, malignant tumor ADC values (2.33±0.44) were higher than those of benign tumors (2.13±0.13). However, there was no significant difference between benign and malignant tumors. Except for high-intensity components on T1-weighted imaging and low or homogeneously very high intensity components on T2-weighted imaging, there was a significant difference in ADC between malignant (1.35±0.40) and benign (1.97±0.50) tumors. Within the limited number of cases, there was a significant difference in ADC between malignant and benign tumors. (author)

  16. Diffusion-weighted MRI of the prostate; Diffusionsgewichtete MRT der Prostata

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Lisse, U.G.; Scherr, M.K. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Mueller-Lisse, U.L. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Klinik und Poliklinik fuer Urologie, Muenchen (Germany); Zamecnik, P.; Schlemmer, H.P.W. [Deutsches Krebsforschungszentrum (DKFZ), Abteilung fuer Radiologische Diagnostik, Heidelberg (Germany)

    2011-03-15

    Diffusion-weighted magnetic resonance imaging (DWI) can complement MRI of the prostate in the detection and localization of prostate cancer, particularly after previous negative biopsy. A total of 13 original reports and 2 reviews published in 2010 demonstrate that prostate cancer can be detected by DWI due to its increased cell density and decreased diffusiveness, either qualitatively in DWI images or quantitatively by means of the apparent diffusion coefficient (ADC). In the prostate, the ADC is influenced by the strength of diffusion weighting, localization (peripheral or transitional zone), presence of prostatitis or hemorrhage and density and differentiation of prostate cancer cells. Mean differences between healthy tissue of the peripheral zone and prostate cancer appear to be smaller for ADC than for the (choline + creatine)/citrate ratio in MR spectroscopy. Test quality parameters vary greatly between different studies but appear to be slightly better for combined MRI and DWI than for MRI of the prostate alone. Clinical validation of DWI of the prostate requires both increased technical conformity and increased numbers of patients in clinical studies. (orig.) [German] Die diffusionsgewichtete MRT (''diffusion-weighted imaging'', DWI) kann die MRT der Prostata bei der Erkennung und Lokalisation von Prostatakarzinomen besonders nach vorangehender, negativer Stanzbiopsie ergaenzen. In 13 klinischen Original- und 2 Uebersichtsarbeiten des Jahres 2010 zeigt sich, dass die DWI Prostatakarzinome an Einschraenkungen der freien Teilchenbeweglichkeit bei erhoehter Zelldichte qualitativ im Bild oder quantitativ an Hand des ''apparent diffusion coefficient'' (ADC) nachweist. Den ADC in der Prostata beeinflussen Staerke der Diffusionsgewichtung, Lokalisation (periphere Zone, Transitionalzone), Vorliegen von Prostatitis oder Einblutung sowie Streudichte und Differenzierung von Prostatakarzinomzellen. Unterschiede zwischen gesundem

  17. Evaluation of malignant and benign renal lesions using diffusion-weighted MRI with multiple b values

    International Nuclear Information System (INIS)

    Erbay, Gurcan; Koc, Zafer; Karadeli, Elif; Kuzgunbay, Baris; Goren, M. Resit; Bal, Nebil

    2012-01-01

    Background: Limited data are available regarding the use of diffusion-weighted (DW) magnetic resonance imaging (MRI) with multiple b values for characterization of renal lesions. Purpose: To demonstrate and compare the diagnostic performance of DW-MRI with multiple b values for renal lesion characterization. Material and Methods: Sixty-three lesions (36 malignant, 27 benign) in 60 consecutive patients (48 men, 12 women; age 60 ± 12.5 years) with solid/cystic renal lesion diagnosed after MRI were included prospectively. Single-shot echo-planar DW abdominal MRI (1.5T) was obtained using seven b values with eight apparent diffusion coefficient (ADC) maps. Contrast-to-noise ratios (CNRs), signal intensities, lesion ADCs, and lesion/normal parenchyma ADC ratios were analyzed. Receiver-operating characteristic analysis was performed. Results: The mean signal intensities of malignant lesions (at b0, 50, and 200 s/mm 2 ) were significantly lower than those of benign lesions (P 2 . ADC with all b values could better distinguish between benign and malignant lesions. A 1.35 x 10 -3 mm 2 /s threshold ADC value permitted this distinction with 85.2% sensitivity and 65.6% specificity. The lesion/normal parenchyma ADC ratio was more effective than the lesion ADC. Conclusion: In addition to the ADC value, the signal intensity curve on DW images using multiple b values could be helpful for differentiation of malignant and benign renal lesions

  18. Persistent lesion hyperintensity on brain diffusion-weighted MRI is an early sign of intravascular lymphoma.

    Science.gov (United States)

    Kageyama, Takashi; Yamanaka, Haruo; Nakamura, Fumihiko; Suenaga, Toshihiko

    2017-06-08

    A 63-year-old man presented with right-sided hemianopia and unsteady gait. Brain MRI revealed multiple hyperintense infarct-like lesions on diffusion-weighted images (DWI). Hyperintensity persisted in some of these lesions even after 6 weeks, although his symptoms were ameliorated then. The patient developed episodic dizziness and a transient event of apraxia at 18 weeks after the first episode. Brain MRI revealed additional hyperintense lesions on DWI, which persisted even after 7 weeks. Eventually, the patient manifested cauda equina syndrome 39 weeks after the first episode. Brain MRI showed the presence of new lesions in addition to the persistent hyperintense lesions on DWI over 21 weeks in the right frontal lobe. Based on laboratory findings and the pathological assessment of bone marrow and random skin biopsies, the patient was diagnosed with intravascular lymphoma (IVL). Persistent hyperintense lesions on DWI of brain MRI may precede the clinical exacerbation of IVL. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Diffusion-Weighted MRI for the Assessment of Liver Fibrosis: Principles and Applications

    Directory of Open Access Journals (Sweden)

    Stefano Palmucci

    2015-01-01

    Full Text Available The importance of an early identification of hepatic fibrosis has been emphasized, in order to start therapy and obtain fibrosis regression. Biopsy is the gold-standard method for the assessment of liver fibrosis in chronic liver diseases, but it is limited by complications, interobserver variability, and sampling errors. Several noninvasive methods have been recently introduced into clinical routine, in order to detect liver fibrosis early. One of the most diffuse approaches is represented by diffusion-weighted liver MRI. In this review, the main technical principles are briefly reported in order to explain the rationale for clinical applications. In addition, roles of apparent diffusion coefficient, intravoxel incoherent motion, and relative apparent diffusion coefficient are also reported, showing their advantages and limits.

  20. Assessment of renal fibrosis in chronic kidney disease using diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Zhao, J.; Wang, Z.J.; Liu, M.; Zhu, J.; Zhang, X.; Zhang, T.; Li, S.; Li, Y.

    2014-01-01

    Aim: To assess the performance of diffusion-weighted magnetic resonance imaging (MRI) for the assessment of renal fibrosis in chronic kidney disease (CKD), with histopathology as a reference standard. Materials and methods: Forty patients with CKD and 30 healthy volunteers were recruited for the study. All participants underwent diffusion-weighted MRI. Renal biopsy was performed in 25 patients with CKD. Mean renal medullary and cortical apparent diffusion coefficient (ADC) values were compared between CKD patients and the healthy volunteers. Pearson's correlation coefficient was calculated to investigate the relationship between ADC values, serum creatinine (SCr), estimated glomerular filtration rate (eGFR), 24 h urinary protein (24h-UPRO), and renal histopathological scores. Results: Cortical and medullary ADC values in the CKD group were significantly lower compared to those in the healthy controls. In the CKD group, a significant negative correlation was found between cortical ADC values and SCr/24h-UPRO, and significant positive correlation was found between cortical ADC and eGFR. There was also a significant negative correlation between medullary ADC values and SCr. Both cortical and medullary ADC values were significantly correlated with histopathological fibrosis score. Conclusion: Renal ADC values strongly correlate with histological measures of fibrosis, and have the potential to enhance the non-invasive monitoring of chronic kidney disease. - Highlights: • Renal ADC values in the CKD patients were lower than those in controls. • Renal ADC values were strongly correlated with histological fibrosis score. • Renal ADC values have the potential to enhance the noninvasive monitoring of CKD

  1. Diffusion-weighted MRI of kidneys in healthy volunteers and living kidney donors

    International Nuclear Information System (INIS)

    Sulkowska, K.; Palczewski, P.; Duda-Zysk, A.; Szeszkowski, W.; Wojcik, D.; Kownacka-Piotrowska, D.; Gołebiowski, M.

    2015-01-01

    Aim: To establish the normal apparent diffusion coefficient (ADC) values in healthy kidneys, comparing them with the literature, and assessing the correlation between ADC values, creatinine blood level, and glomerular filtration rate (GFR). Materials and methods: Twenty-four healthy volunteers and 26 living kidney donors were examined on a 1.5 T magnetic resonance imaging (MRI) unit. Two diffusion-weighted imaging (DWI) sequences were included in the study protocol (protocol 1 with 16 b-values, protocol 2 with 10 b-values) before the examination blood and urine samples were collected. The GFR was calculated using Cockcroft & Gault and MDRD (Modification of Diet In Renal Disease) formulas and the ADC values were measured separately for the cortex and medulla of each kidney by two independent observers. All statistical analyses were performed using the STATISTICA (version 10.0) software package. Data were analysed using an unpaired t-test; p<0.05 indicated a statistically significant difference. Results: The average ADC value for protocol 1 for the cortex was 2.26×10 −3  mm 2 /s, for the medulla 2.21×10 −3  mm 2 /s. In protocol 2, the respective values were 2.13×10 −3  mm 2 /s and 2.06×10 −3  mm 2 /s. Neither statistically significant interobserver differences nor correlation between ADC values, GFR, and creatinine serum level were observed. Conclusion: The reference ADC values were established. The measurements show high interobserver consistency. The differences in ADC values reported in the literature suggest dependence on the equipment and methodology and point to the necessity of obtaining ADC norms for each MRI unit. -- Highlights: •Magnetic resonance diffusion-weighted imaging of kidneys. •Apparent diffusion coefficient in healthy individuals. •Monoexponential model of diffusion

  2. 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.

  3. Diffusion-weighted MRI for detecting prostate tumour in men at increased genetic risk

    International Nuclear Information System (INIS)

    Souza, Nandita M. de; Morgan, Veronica A.; Bancroft, Elizabeth; Sohaib, S. Aslam; Giles, Sharon L.; Kote-Jarai, Zsofia; Castro, Elena; Hazell, Steven; Jafar, Maysam; Eeles, Rosalind

    2014-01-01

    •Endorectal T2W + DW-MRI is potentially useful for prostate cancer screening.•MRI is specific for detecting prostate cancer in men with increased genetic risk.•Detection of prostate cancer in men at genetically low risk with MRI is limited. Endorectal T2W + DW-MRI is potentially useful for prostate cancer screening. MRI is specific for detecting prostate cancer in men with increased genetic risk. Detection of prostate cancer in men at genetically low risk with MRI is limited. Diffusion-weighted (DW)-MRI is invaluable in detecting prostate cancer. We determined its sensitivity and specificity and established interobserver agreement for detecting tumour in men with a family history of prostate cancer stratified by genetic risk. 51 men with a family history of prostate cancer underwent T2-W + DW-endorectal MRI at 3.0 T. Presence of tumour was noted at right and left apex, mid and basal prostate sextants by 2 independent observers, 1 experienced and the other inexperienced in endorectal MRI. Sensitivity and specificity against a 10-core sampling technique (lateral and medial cores at each level considered together) in men with >2× population risk based on 71 SNP analysis versus those with lower genetic risk scores was established. Interobserver agreement was determined at a subject level. Biopsies indicated cancer in 28 sextants in 13/51 men; 32 of 51 men had twice the population risk (>0.25) based on 71 SNP profiling. Sensitivity/specificity per-subject for patients was 90.0%/86.4% (high-risk) vs. 66.7%/100% (low-risk, observer 1) and 60.0%/86.3% (high-risk) vs. 33.3%/93.8% (low-risk, observer 2) with moderate overall inter-observer agreement (kappa = 0.42). Regional sensitivities/specificities for high-risk vs. low-risk for observer 1 apex 72.2%/100% [33.3%/100%], mid 100%/93.1% [100%/97.3%], base 16.7%/98.3% [0%/100%] and for observer 2 apex 36.4%/98.1% [0%/100%], mid 28.6%/96.5% [100%/100%], base 20%/100% [0%/97.3%] were poorer as they failed to detect

  4. Clinical usefulness of diffusion-weighted MRI in various stages of ischemic stroke

    International Nuclear Information System (INIS)

    Song, So Youne; Cho, Woo Ho; Kim, Soung Hee; Kim, Jung Sook; Kim, Young Hoon; Kim, Myung Gyu; Hur, Gham

    2002-01-01

    Diffusion-weighted MRI (DWI) is well known to be sensitive in the detection of hyperacute infarct, but has not been systematically investigated in patients with acute or subacute infarct. We evaluated the usefulness of diffusion-weighted MRI in assessing the various stages of brain infarct. Fifty-five consecutive patients with symptoms of brain infarct underwent fast spinecho T2-weighted MRI (T2WI) and DWI. Using only a brief clinical history, two radiologists first attempted to detect the lesion using T2W1, which was then compared with DWI. The usefulness of the latter was then evaluated in terms of the following criteria: 1) Its abilility to detect a lesion not seen at T2WI(detection); 2) localization of the responsible ischemic focus among multiple high-signal intensities seen at T2WI (localization); 3) conspicuity of a lesion which was subtle at T2WI (conspicuity); 4) detection of multiple lesions (multiplicity). DWI was useful in 44 of 55 patients (80%), including 9 of 9 (100%) with hyperacute infarct (<6 hours), 20 of 27 (74%) with acute infarct (<48 hours), and 15 of 19 (79%) with subacute infarct (<2 weeks). Among the nine patients at the hyperacute stage, DWI was useful for detection of the lesion in six (67%), for localization, 4 (44%) in one (11%), for conspicuity in four (44%), and for multiplicity in five (56%); at the acute stage (20 patients), for detection in three (15%), for localization in ten (50%), for conspicuity in eight (40%), and for moltiplicity in five (25%); and at the subacute stage (15 patients), for detection in three (20%), for localization in nine (60%), for conspicuity in two (13%), and for multiplicity in three (20%). DWI is very sensitive for the diagnosis of hyperacute infarct. In the assessment of this, it is useful during the acute or subacute period for the detection of small lesions, the localization of ongoing lesions among multiple high signal intensities seen at T2WI, and the determination of lesion conspicuity

  5. Diffusion-weighted (DW) MRI in lung cancers. ADC test-retest repeatability

    Energy Technology Data Exchange (ETDEWEB)

    Weller, Alex; Papoutsaki, Marianthi Vasiliki; Blackledge, Matthew; DeSouza, Nandita M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, CRUK Cancer Imaging Centre, Surrey (United Kingdom); Waterton, John C. [University of Manchester, Manchester (United Kingdom); Chiti, Arturo [Humanitas University, Milan (Italy); Stroobants, Sigrid [Universiteit Antwerpen, Antwerpen (Belgium); Kuijer, Joost [Vrije Universiteit Medisch Centrum, Amsterdam (Netherlands); Morgan, Veronica [Royal Marsden NHS Foundation Trust, Department of Medicine, London (United Kingdom)

    2017-11-15

    To determine the test-retest repeatability of Apparent Diffusion Coefficient (ADC) measurements across institutions and MRI vendors, plus investigate the effect of post-processing methodology on measurement precision. Thirty malignant lung lesions >2 cm in size (23 patients) were scanned on two occasions, using echo-planar-Diffusion-Weighted (DW)-MRI to derive whole-tumour ADC (b = 100, 500 and 800 s/mm{sup -2}). Scanning was performed at 4 institutions (3 MRI vendors). Whole-tumour volumes-of-interest were copied from first visit onto second visit images and from one post-processing platform to an open-source platform, to assess ADC repeatability and cross-platform reproducibility. Whole-tumour ADC values ranged from 0.66-1.94x10{sup -3} mm{sup 2}s{sup -1} (mean = 1.14). Within-patient coefficient-of-variation (wCV) was 7.1% (95% CI 5.7-9.6%), limits-of-agreement (LoA) -18.0 to 21.9%. Lesions >3 cm had improved repeatability: wCV 3.9% (95% CI 2.9-5.9%); and LoA -10.2 to 11.4%. Variability for lesions <3 cm was 2.46 times higher. ADC reproducibility across different post-processing platforms was excellent: Pearson's R{sup 2} = 0.99; CoV 2.8% (95% CI 2.3-3.4%); and LoA -7.4 to 8.0%. A free-breathing DW-MRI protocol for imaging malignant lung tumours achieved satisfactory within-patient repeatability and was robust to changes in post-processing software, justifying its use in multi-centre trials. For response evaluation in individual patients, a change in ADC >21.9% will reflect treatment-related change. (orig.)

  6. Benign and malignant skull-involved lesions: discriminative value of conventional CT and MRI combined with diffusion-weighted MRI.

    Science.gov (United States)

    Tu, Zhanhai; Xiao, Zebin; Zheng, Yingyan; Huang, Hongjie; Yang, Libin; Cao, Dairong

    2018-01-01

    Background Little is known about the value of computed tomography (CT) and magnetic resonance imaging (MRI) combined with diffusion-weighted imaging (DWI) in distinguishing malignant from benign skull-involved lesions. Purpose To evaluate the discriminative value of DWI combined with conventional CT and MRI for differentiating between benign and malignant skull-involved lesions. Material and Methods CT and MRI findings of 58 patients with pathologically proven skull-involved lesions (43 benign and 15 malignant) were retrospectively reviewed. Conventional CT and MRI characteristics and apparent diffusion coefficient (ADC) value of the two groups were evaluated and compared. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the differential performance of each parameter separately and together. Results The presence of cortical defects or break-through and ill-defined margins were associated with malignant skull-involved lesions (both P benign and malignant skull-involved lesions. Conclusion The combination of CT, MRI, and DWI can help to differentiate malignant from benign skull-involved lesions. CT + MRI + DWI offers optimal sensitivity, while DWI offers optimal specificity.

  7. Correlation of diffusion-weighted MRI and gross anatomy of rat kidneys

    International Nuclear Information System (INIS)

    Chen Rongfeng; Wu Xiaomei; Chen Xiaoyan; Deng Yu; Li Xinchun; He Jianxun; Li Huiming

    2011-01-01

    Objective: To investigate the feasibility and accuracy of diffusion-weighted MRI in differentiating the cortico-medullary layers of rat kidneys. Methods: Twelve rats underwent MRI using a 1.5 Tesla system including DWI of various b-values, T1WI and T 2 WI sequences. The MR characteristics and thickness of renal cortico-medullary layers compared to those of the gross anatomical layers. Results: On the longitudinal anatomical sections of the kidneys, four parenchymal layers of cortex (CO), the outer (OS) and inner (IS) stripes of the outer medulla (OM), the inner medulla (IM) and renal pelvis could be clearly recognized. The numbers of layers visible on MRI varied with different pulse sequences. Single layers of cortex and medulla were visible on T 1 WI. CO, OM and IM were delineated on T 2 WI. CO, OS, IS and IM were clearly identified on DWI and ADC maps. DWI was significantly superior to T 1 WI and T 2 WI for displaying the renal parenchymal layers (P 0.05) from the measurements on DWI (CO: 1.39±0.15 mm, OS: 1.01±0.17 mm, IS: 1.11±0.19 mm, IM: 1.06±0.10 mm). Different b-values of DWI did not show significant difference in depiction of the parenchyma (P>0.05). Conclusion: Four parenchymal layers shown on DWI correlated well with gross anatomical structure and may be used in imaging study of rat kidneys. (authors)

  8. Diffusion-weighted MRI of malignant versus benign portal vein thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Jhii Hyun; Yu, Jeong Sik; Cho, Eun Suk; Chung, Jae Joon; Kim, Joo Hee; Kim, Ki Whang [Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul(Korea, Republic of)

    2016-07-15

    To validate the diffusion-weighted MRI (DWI) for differentiation of benign from malignant portal vein thrombosis. The Institutional Review Board approved this retrospective study and waived informed consent. A total of 59 consecutive patients (52 men and 7 women, aged 40-85 years) with grossly defined portal vein thrombus (PVT) on hepatic MRI were retrospectively analyzed. Among them, liver cirrhosis was found in 45 patients, and hepatocellular carcinoma in 47 patients. DWI was performed using b values of 50 and 800 sec/mm2 at 1.5-T unit. A thrombus was considered malignant if it enhanced on dynamic CT or MRI; otherwise, it was considered bland. There were 18 bland thrombi and 49 malignant thrombi in 59 patients, including 8 patients with simultaneous benign and malignant PVT. Mean apparent diffusion coefficients (ADCs) of benign and malignant PVTs were compared by using Mann-Whitney U test. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curve analysis. The mean ADC ± standard deviation of bland and malignant PVT were 1.00 ± 0.39 × 10(-3) mm{sup 2}/sec and 0.92 ± 0.25 × 10(-3) mm{sup 2}/sec, respectively; without significant difference (p = 0.799). The area under ROC curve for ADC was 0.520. An ADC value of > 1.35 × 10(-3) mm{sup 2}/sec predicted bland PVT with a specificity of 94.6% (95% confidence interval [CI]: 84.9-98.9%) and a sensitivity of 22.2% (95% CI: 6.4-47.6%), respectively. Due to the wide range and considerable overlap of the ADCs, DWI cannot differentiate the benign from malignant thrombi efficiently.

  9. Diffusion-weighted MRI of malignant versus benign portal vein thrombosis

    International Nuclear Information System (INIS)

    Ahn, Jhii Hyun; Yu, Jeong Sik; Cho, Eun Suk; Chung, Jae Joon; Kim, Joo Hee; Kim, Ki Whang

    2016-01-01

    To validate the diffusion-weighted MRI (DWI) for differentiation of benign from malignant portal vein thrombosis. The Institutional Review Board approved this retrospective study and waived informed consent. A total of 59 consecutive patients (52 men and 7 women, aged 40-85 years) with grossly defined portal vein thrombus (PVT) on hepatic MRI were retrospectively analyzed. Among them, liver cirrhosis was found in 45 patients, and hepatocellular carcinoma in 47 patients. DWI was performed using b values of 50 and 800 sec/mm2 at 1.5-T unit. A thrombus was considered malignant if it enhanced on dynamic CT or MRI; otherwise, it was considered bland. There were 18 bland thrombi and 49 malignant thrombi in 59 patients, including 8 patients with simultaneous benign and malignant PVT. Mean apparent diffusion coefficients (ADCs) of benign and malignant PVTs were compared by using Mann-Whitney U test. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curve analysis. The mean ADC ± standard deviation of bland and malignant PVT were 1.00 ± 0.39 × 10(-3) mm 2 /sec and 0.92 ± 0.25 × 10(-3) mm 2 /sec, respectively; without significant difference (p = 0.799). The area under ROC curve for ADC was 0.520. An ADC value of > 1.35 × 10(-3) mm 2 /sec predicted bland PVT with a specificity of 94.6% (95% confidence interval [CI]: 84.9-98.9%) and a sensitivity of 22.2% (95% CI: 6.4-47.6%), respectively. Due to the wide range and considerable overlap of the ADCs, DWI cannot differentiate the benign from malignant thrombi efficiently

  10. Diffusion-Weighted MRI of Malignant versus Benign Portal Vein Thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Jhii-Hyun; Yu, Jeong-Sik; Cho, Eun-Suk; Chung, Jae-Joon; Kim, Joo Hee; Kim, Ki Whang [Department of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul 06273 (Korea, Republic of)

    2016-11-01

    To validate the diffusion-weighted MRI (DWI) for differentiation of benign from malignant portal vein thrombosis. The Institutional Review Board approved this retrospective study and waived informed consent. A total of 59 consecutive patients (52 men and 7 women, aged 40–85 years) with grossly defined portal vein thrombus (PVT) on hepatic MRI were retrospectively analyzed. Among them, liver cirrhosis was found in 45 patients, and hepatocellular carcinoma in 47 patients. DWI was performed using b values of 50 and 800 sec/mm{sup 2} at 1.5-T unit. A thrombus was considered malignant if it enhanced on dynamic CT or MRI; otherwise, it was considered bland. There were 18 bland thrombi and 49 malignant thrombi in 59 patients, including 8 patients with simultaneous benign and malignant PVT. Mean apparent diffusion coefficients (ADCs) of benign and malignant PVTs were compared by using Mann-Whitney U test. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curve analysis. The mean ADC ± standard deviation of bland and malignant PVT were 1.00 ± 0.39 × 10{sup -3} mm{sup 2}/sec and 0.92 ± 0.25 × 10{sup -3} mm{sup 2}/sec, respectively; without significant difference (p = 0.799). The area under ROC curve for ADC was 0.520. An ADC value of > 1.35 × 10{sup -3} mm{sup 2}/sec predicted bland PVT with a specificity of 94.6% (95% confidence interval [CI]: 84.9–98.9%) and a sensitivity of 22.2% (95% CI: 6.4–47.6%), respectively. Due to the wide range and considerable overlap of the ADCs, DWI cannot differentiate the benign from malignant thrombi efficiently.

  11. 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.

  12. Diffusion-Weighted MRI of Malignant versus Benign Portal Vein Thrombosis

    International Nuclear Information System (INIS)

    Ahn, Jhii-Hyun; Yu, Jeong-Sik; Cho, Eun-Suk; Chung, Jae-Joon; Kim, Joo Hee; Kim, Ki Whang

    2016-01-01

    To validate the diffusion-weighted MRI (DWI) for differentiation of benign from malignant portal vein thrombosis. The Institutional Review Board approved this retrospective study and waived informed consent. A total of 59 consecutive patients (52 men and 7 women, aged 40–85 years) with grossly defined portal vein thrombus (PVT) on hepatic MRI were retrospectively analyzed. Among them, liver cirrhosis was found in 45 patients, and hepatocellular carcinoma in 47 patients. DWI was performed using b values of 50 and 800 sec/mm 2 at 1.5-T unit. A thrombus was considered malignant if it enhanced on dynamic CT or MRI; otherwise, it was considered bland. There were 18 bland thrombi and 49 malignant thrombi in 59 patients, including 8 patients with simultaneous benign and malignant PVT. Mean apparent diffusion coefficients (ADCs) of benign and malignant PVTs were compared by using Mann-Whitney U test. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curve analysis. The mean ADC ± standard deviation of bland and malignant PVT were 1.00 ± 0.39 × 10 -3 mm 2 /sec and 0.92 ± 0.25 × 10 -3 mm 2 /sec, respectively; without significant difference (p = 0.799). The area under ROC curve for ADC was 0.520. An ADC value of > 1.35 × 10 -3 mm 2 /sec predicted bland PVT with a specificity of 94.6% (95% confidence interval [CI]: 84.9–98.9%) and a sensitivity of 22.2% (95% CI: 6.4–47.6%), respectively. Due to the wide range and considerable overlap of the ADCs, DWI cannot differentiate the benign from malignant thrombi efficiently

  13. Diffusion-weighted imaging findings on MRI as the sole radiographic findings in a child with proven herpes simplex encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Obeid, Makram; Franklin, Jeremy; Shrestha, Shraddha; Johnson, Lara; Hurst, Daniel [Texas Tech University Health Sciences Center, Department of Pediatrics, Lubbock, TX (United States); Quattromani, Frank [Texas Tech University Health Sciences Center, Department of Radiology, Lubbock, TX (United States)

    2007-11-15

    We present a case of herpes simplex encephalitis in an 8-year-old girl, in whom hyperintensity was detected on diffusion-weighted imaging (DWI) while conventional MRI sequences were normal 1 week after the onset of neurological symptoms. This case is rare in that a child beyond the neonatal period with focal herpes simplex encephalitis had an abnormal DWI sequence as the only MRI finding. (orig.)

  14. Diffusion-weighted MRI - a new parameter for advanced rectal carcinoma?

    International Nuclear Information System (INIS)

    Hein, P.A.; Lukas, P.; DeVries, A.F.; Pfeiffer, K.-P.

    2003-01-01

    Purpose: To evaluate the predictive value of apparent diffusion coefficient (ADC) on therapy outcome of combined chemoradiation in patients with primary carcinoma of the rectum. Materials and Method: Prior to standardized, combined, neoadjuvant chemoradiation, 16 patients with primary carcinoma of the rectum (cT3) were examined with magnetic resonance imaging (MRI). Diffusion weighted spin echo echo-planar images (SE-EPI) and contrast-enhanced T 1 -weighted spin echo (SE) images at 1.5 Tesla were obtained. The mean ADC of the tumor region was calculated and correlated with the therapy outcome substantiated by postsurgical histopathologic staging. Results: Tumor downstaging (pT0-2) occurred in 9 patients (therapy responders) and no down-staging (pT3) in 7 patients (therapy non-responders). The mean ADC measured 0.476±0.114 x 10 -3 mm 2 /s in the responder group and 0.703±0.085 x 10 -3 mm 2 /s in the non-responder group. Comparison of the mean ADC between the groups reached statistical significance (p=0.001). Conclusion: The mean ADC might be a new quantitative parameter to predict therapy outcome of combined preoperative chemoradiation in patients with primary carcinoma of the rectum. (orig.) [de

  15. Characterization of ductal carcinoma in situ on diffusion weighted breast MRI

    International Nuclear Information System (INIS)

    Rahbar, Habib; Partridge, Savannah C.; Eby, Peter R.; DeMartini, Wendy B.; Gutierrez, Robert L.; Peacock, Sue; Lehman, Constance D.

    2011-01-01

    To characterize ductal carcinoma in situ (DCIS) and its subtypes on diffusion-weighted imaging (DWI). We retrospectively reviewed 74 pure DCIS lesions in 69 women who underwent DWI at 1.5 T (b = 0 and 600 s/mm 2 ). Each lesion was characterized by qualitative DWI intensity, quantitative DWI lesion-to-normal contrast-to-noise ratio (CNR), and quantitative apparent diffusion coefficient (ADC). The detection rate was calculated with predetermined thresholds for each parameter. The effects of lesion size, grade, morphology, and necrosis were assessed. Ninety-six percent (71/74) of DCIS lesions demonstrated greater qualitative DWI intensity than normal breast tissue. Quantitatively, DCIS lesions demonstrated on average 56% greater signal than normal tissue (mean CNR = 1.83 ± 2.7) and lower ADC values (1.50 ± 0.28 x 10 -3 mm 2 /s) than normal tissue (2.01 ± 0.37 x 10 -3 mm 2 /s, p -3 mm 2 /s). Non-high-grade DCIS exhibited greater qualitative DWI intensity (p = 0.02) and quantitative CNR (p = 0.01) than high-grade DCIS but no difference in ADC (p = 0.40). Lesion size, morphology, and necrosis did not affect qualitative or quantitative DWI parameters of DCIS lesions (p > 0.05). DCIS lesions have higher DWI signal intensity and lower ADC values than normal breast tissue. DWI warrants further investigation as a potential non-contrast MRI tool for early breast cancer detection. (orig.)

  16. Patterns in early diffusion-weighted MRI in children with haemolytic uraemic syndrome and CNS involvement

    International Nuclear Information System (INIS)

    Donnerstag, Frank; Ding, Xiaoqi; Bueltmann, Eva; Zajaczek, Jan; Lanfermann, Heinrich; Pape, Lars; Das, Anibh Martin; Ehrich, Jochen; Hartmann, Hans; Luecke, Thomas; Hoy, Ludwig

    2012-01-01

    Diffusion-weighted imaging (DWI) in children with diarrhoea associated haemolytic uraemic syndrome (D+HUS) and cerebral involvement was evaluated retrospectively. DWI within 24 h of onset of neurological symptoms. The apparent diffusion coefficient (ADC) was measured in grey/white matter and correlated with clinical and laboratory findings. DWI was abnormal in all. Abnormal ADC was detected in the supratentorial white matter (6/12) and cortex (1/12), the basal ganglia (5/12), the thalami (4/12), and the cerebellum (1/12). ADC was reduced in 5/12, increased in 4/12, and both in 3/12. Mean serum sodium was lower in patients with DWI abnormalities affecting the white matter (6/12), than in those with basal ganglia/thalamic involvement (6/12). Neurological outcome was normal in 4/11 and abnormal in 7/11, and 1 patient died, outcome did not correlate to either localisation or type of DWI abnormality. In D+HUS with neurological symptoms, early DWI may reveal abnormal ADC not only in the basal ganglia/thalami, but also in the white matter/cortex. Besides thrombotic microangiopathy, toxic effects of shiga toxin, azotaemia and hyponatraemia / hypoosmolality may be involved in cerebral involvement in children with D+HUS. Findings on early MRI seem not to predict clinical course or outcome. (orig.)

  17. 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)

  18. Patterns in early diffusion-weighted MRI in children with haemolytic uraemic syndrome and CNS involvement

    Energy Technology Data Exchange (ETDEWEB)

    Donnerstag, Frank; Ding, Xiaoqi; Bueltmann, Eva; Zajaczek, Jan; Lanfermann, Heinrich [Hannover Medical School, Institute of Diagnostic and Therapeutic Neuroradiology, Hannover (Germany); Pape, Lars; Das, Anibh Martin; Ehrich, Jochen; Hartmann, Hans [Hannover Medical School, Clinic for Pediatric Kidney, Liver and Metabolic Diseases, Hannover (Germany); Luecke, Thomas [Hannover Medical School, Clinic for Pediatric Kidney, Liver and Metabolic Diseases, Hannover (Germany); University of Bochum, Department of Neuropediatrics, Pediatric Hospital, Bochum (Germany); Hoy, Ludwig [Hannover Medical School, Institute of Biometrics, Hannover (Germany)

    2012-03-15

    Diffusion-weighted imaging (DWI) in children with diarrhoea associated haemolytic uraemic syndrome (D+HUS) and cerebral involvement was evaluated retrospectively. DWI within 24 h of onset of neurological symptoms. The apparent diffusion coefficient (ADC) was measured in grey/white matter and correlated with clinical and laboratory findings. DWI was abnormal in all. Abnormal ADC was detected in the supratentorial white matter (6/12) and cortex (1/12), the basal ganglia (5/12), the thalami (4/12), and the cerebellum (1/12). ADC was reduced in 5/12, increased in 4/12, and both in 3/12. Mean serum sodium was lower in patients with DWI abnormalities affecting the white matter (6/12), than in those with basal ganglia/thalamic involvement (6/12). Neurological outcome was normal in 4/11 and abnormal in 7/11, and 1 patient died, outcome did not correlate to either localisation or type of DWI abnormality. In D+HUS with neurological symptoms, early DWI may reveal abnormal ADC not only in the basal ganglia/thalami, but also in the white matter/cortex. Besides thrombotic microangiopathy, toxic effects of shiga toxin, azotaemia and hyponatraemia / hypoosmolality may be involved in cerebral involvement in children with D+HUS. Findings on early MRI seem not to predict clinical course or outcome. (orig.)

  19. 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.)

  20. Comparison of CT and diffusion-weighted MRI in acute ischemic stroke

    International Nuclear Information System (INIS)

    Moriwaki, Hiroshi; Okazaki, Shuhei; Yamada, Naoaki; Naritomi, Hiroaki

    2006-01-01

    Non-contrast CT and diffusion-weighted MRI (DWI) are widely used for assessing patients with acute ischemic stroke including candidates for thrombolytic therapy. Early CT signs, still a gold standard as the diagnostic measure for thrombolysis, are quite subtle and strongly depend on image quality. We evaluated 76 patients (47 male, mean age 71.0 yrs) with ischemic stroke of the anterior cerebral circulation who underwent CT and DWI within 6 hours of onset. The scans were examined separately by two neurologists in a blinded fashion with knowledge of the affected hemisphere. Detection of acute ischemic changes were significantly higher on DWI (72/76, 95%) compared with that on CT (50/76, 66%) (P<0.0001), especially in cases with subcortical lesions (P<0.001). Detection of the lesion with more than 33% of MCA involvement, which should exclude from the thrombolitic therapy, was somewhat higher for DWI (26/26, 100%) compared with CT (22/26, 85%). DWI is more sensitive than CT in the identification of acute ischemic stroke and can visualize major ischemia more easily than CT. Additional studies are required to determine whether these advantages of DWI are clinically relevant in the management of patients with acute stroke. (author)

  1. 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.)

  2. Diffusion-weighted MRI characteristics of the cerebral metastasis to brain boundary predicts patient outcomes

    International Nuclear Information System (INIS)

    Zakaria, Rasheed; Das, Kumar; Radon, Mark; Bhojak, Maneesh; Rudland, Philip R; Sluming, Vanessa; Jenkinson, Michael D

    2014-01-01

    Diffusion-weighted MRI (DWI) has been used in neurosurgical practice mainly to distinguish cerebral metastases from abscess and glioma. There is evidence from other solid organ cancers and metastases that DWI may be used as a biomarker of prognosis and treatment response. We therefore investigated DWI characteristics of cerebral metastases and their peritumoral region recorded pre-operatively and related these to patient outcomes. Retrospective analysis of 76 cases operated upon at a single institution with DWI performed pre-operatively at 1.5T. Maps of apparent diffusion coefficient (ADC) were generated using standard protocols. Readings were taken from the tumor, peritumoral region and across the brain-tumor interface. Patient outcomes were overall survival and time to local recurrence. A minimum ADC greater than 919.4 × 10 -6 mm 2 /s within a metastasis predicted longer overall survival regardless of adjuvant therapies. This was not simply due to differences between the types of primary cancer because the effect was observed even in a subgroup of 36 patients with the same primary, non-small cell lung cancer. The change in diffusion across the tumor border and into peritumoral brain was measured by the “ADC transition coefficient” or ATC and this was more strongly predictive than ADC readings alone. Metastases with a sharp change in diffusion across their border (ATC >0.279) showed shorter overall survival compared to those with a more diffuse edge. The ATC was the only imaging measurement which independently predicted overall survival in multivariate analysis (hazard ratio 0.54, 95% CI 0.3 – 0.97, p = 0.04). DWI demonstrates changes in the tumor, across the tumor edge and in the peritumoral region which may not be visible on conventional MRI and this may be useful in predicting patient outcomes for operated cerebral metastases

  3. Support vector machine for breast cancer classification using diffusion-weighted MRI histogram features: Preliminary study.

    Science.gov (United States)

    Vidić, Igor; Egnell, Liv; Jerome, Neil P; Teruel, Jose R; Sjøbakk, Torill E; Østlie, Agnes; Fjøsne, Hans E; Bathen, Tone F; Goa, Pål Erik

    2018-05-01

    Diffusion-weighted MRI (DWI) is currently one of the fastest developing MRI-based techniques in oncology. Histogram properties from model fitting of DWI are useful features for differentiation of lesions, and classification can potentially be improved by machine learning. To evaluate classification of malignant and benign tumors and breast cancer subtypes using support vector machine (SVM). Prospective. Fifty-one patients with benign (n = 23) and malignant (n = 28) breast tumors (26 ER+, whereof six were HER2+). Patients were imaged with DW-MRI (3T) using twice refocused spin-echo echo-planar imaging with echo time / repetition time (TR/TE) = 9000/86 msec, 90 × 90 matrix size, 2 × 2 mm in-plane resolution, 2.5 mm slice thickness, and 13 b-values. Apparent diffusion coefficient (ADC), relative enhanced diffusivity (RED), and the intravoxel incoherent motion (IVIM) parameters diffusivity (D), pseudo-diffusivity (D*), and perfusion fraction (f) were calculated. The histogram properties (median, mean, standard deviation, skewness, kurtosis) were used as features in SVM (10-fold cross-validation) for differentiation of lesions and subtyping. Accuracies of the SVM classifications were calculated to find the combination of features with highest prediction accuracy. Mann-Whitney tests were performed for univariate comparisons. For benign versus malignant tumors, univariate analysis found 11 histogram properties to be significant differentiators. Using SVM, the highest accuracy (0.96) was achieved from a single feature (mean of RED), or from three feature combinations of IVIM or ADC. Combining features from all models gave perfect classification. No single feature predicted HER2 status of ER + tumors (univariate or SVM), although high accuracy (0.90) was achieved with SVM combining several features. Importantly, these features had to include higher-order statistics (kurtosis and skewness), indicating the importance to account for heterogeneity. Our

  4. A biomimetic tumor tissue phantom for validating diffusion-weighted MRI measurements.

    Science.gov (United States)

    McHugh, Damien J; Zhou, Feng-Lei; Wimpenny, Ian; Poologasundarampillai, Gowsihan; Naish, Josephine H; Hubbard Cristinacce, Penny L; Parker, Geoffrey J M

    2018-07-01

    To develop a biomimetic tumor tissue phantom which more closely reflects water diffusion in biological tissue than previously used phantoms, and to evaluate the stability of the phantom and its potential as a tool for validating diffusion-weighted (DW) MRI measurements. Coaxial-electrospraying was used to generate micron-sized hollow polymer spheres, which mimic cells. The bulk structure was immersed in water, providing a DW-MRI phantom whose apparent diffusion coefficient (ADC) and microstructural properties were evaluated over a period of 10 months. Independent characterization of the phantom's microstructure was performed using scanning electron microscopy (SEM). The repeatability of the construction process was investigated by generating a second phantom, which underwent high resolution synchrotron-CT as well as SEM and MR scans. ADC values were stable (coefficients of variation (CoVs) < 5%), and varied with diffusion time, with average values of 1.44 ± 0.03 µm 2 /ms (Δ = 12 ms) and 1.20 ± 0.05 µm 2 /ms (Δ = 45 ms). Microstructural parameters showed greater variability (CoVs up to 13%), with evidence of bias in sphere size estimates. Similar trends were observed in the second phantom. A novel biomimetic phantom has been developed and shown to be stable over 10 months. It is envisaged that such phantoms will be used for further investigation of microstructural models relevant to characterizing tumor tissue, and may also find application in evaluating acquisition protocols and comparing DW-MRI-derived biomarkers obtained from different scanners at different sites. Magn Reson Med 80:147-158, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is

  5. Is diffusion-weighted MRI sufficient for follow-up of neuroendocrine tumour liver metastases?

    International Nuclear Information System (INIS)

    Lavelle, L.P.; O'Neill, A.C.; McMahon, C.J.; Cantwell, C.P.; Heffernan, E.J.; Malone, D.E.; Daly, L.; Skehan, S.J.

    2016-01-01

    Aim: To assess if diffusion-weighted imaging (DWI) alone could be used for follow-up of neuroendocrine hepatic metastases. Material and methods: This was a retrospective study, approved by the institutional review board. Twenty-two patients with neuroendocrine liver metastases who had undergone more than one liver magnetic resonance imaging (MRI) examination, (including DWI and using hepatocyte-specific contrast medium) were evaluated. Up to five metastases were measured at baseline and at each subsequent examination. The reference standard measurement was performed on the hepatocyte phase by one reader. Three independent readers separately measured the same lesions on DWI sequences alone, blinded to other sequences, and recorded the presence of any new lesions. Results: The longest diameters of 317 liver metastases (91 on 22 baseline examinations and a further 226 measurements on follow-up) were measured on the reference standard by one reader and on three b-values by three other readers. The mean difference between DWI measurements and the reference standard measurement was between 0.01–0.08 cm over the nine reader/b-value combinations. Based on the width of the Bland and Altman interval containing approximately 95% of the differences between the reader observation and the mean of reference standard and DWI measurement, the narrowest interval over the nine reader/b-value combinations was −0.6 to +0.7 cm and the widest was −0.9 to 1 cm. In the evaluation of overall response using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria, the weighted kappa statistic was between 0.49 and 0.86, indicating moderate-to-good agreement between the reference standard and DWI. Conclusion: The visualisation and measurement of hepatic metastases using DWI alone are within acceptable limits for clinical use, allowing the use of this rapid technique to restage hepatic disease in patients with neuroendocrine metastases. - Highlights: • DWI showed excellent

  6. CADrx for GBM Brain Tumors: Predicting Treatment Response from Changes in Diffusion-Weighted MRI

    Directory of Open Access Journals (Sweden)

    Matthew S. Brown

    2009-11-01

    Full Text Available The goal of this study was to develop a computer-aided therapeutic response (CADrx system for early prediction of drug treatment response for glioblastoma multiforme (GBM brain tumors with diffusion weighted (DW MR images. In conventional Macdonald assessment, tumor response is assessed nine weeks or more post-treatment. However, we will investigate the ability of DW-MRI to assess response earlier, at five weeks post treatment. The apparent diffusion coefficient (ADC map, calculated from DW images, has been shown to reveal changes in the tumor’s microenvironment preceding morphologic tumor changes. ADC values in treated brain tumors could theoretically both increase due to the cell kill (and thus reduced cell density and decrease due to inhibition of edema. In this study, we investigated the effectiveness of features that quantify changes from pre- and post-treatment tumor ADC histograms to detect treatment response. There are three parts to this study: first, tumor regions were segmented on T1w contrast enhanced images by Otsu’s thresholding method, and mapped from T1w images onto ADC images by a 3D region of interest (ROI mapping tool using DICOM header information; second, ADC histograms of the tumor region were extracted from both pre- and five weeks post-treatment scans, and fitted by a two-component Gaussian mixture model (GMM. The GMM features as well as standard histogram-based features were extracted. Finally, supervised machine learning techniques were applied for classification of responders or non-responders. The approach was evaluated with a dataset of 85 patients with GBM under chemotherapy, in which 39 responded and 46 did not, based on tumor volume reduction. We compared adaBoost, random forest and support vector machine classification algorithms, using ten-fold cross validation, resulting in the best accuracy of 69.41% and the corresponding area under the curve (Az of 0.70.

  7. Detectability and detection rate of acute cerebral hemisphere infarcts on CT and diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Urbach, H.; Flacke, S.; Keller, E.; Textor, J.; Berlis, A.; Reul, J.; Schild, H.H.; Hartmann, A.; Solymosi, L.

    2000-01-01

    Our purpose was to compare the detectability and detection rate of acute ischaemic cerebral hemisphere infarcts on CT and diffusion-weighted MRI (DWI). We investigated 32 consecutive patients with acute hemisphere stroke with unenhanced CT and DWI within 6 h of stroke onset. The interval between CT and DWI ranged from 15 to 180 min (mean 60 min). Infarct detectability on CT and DWI was determined by comparing the initial CT, DWI and later reference images in a consensus reading of five independent examiners. The ''true'' detection rate was assessed by analysing all single readings. Two patients had intracerebral haematomas on DWI and CT and were excluded. There were 27 patients with ischaemic infarcts; all were visible on DWI and proven by follow-up. DWI was negative in three patients without a final diagnosis of infarct (100 % sensitivity, 100 % specificity, χ 2 = 30, P 2 = 1.48, P = 0.224). With regard to the single readings (30 examinations x 5 examiners = 150 readings), 63 CT readings were true positive and 72 false negative (sensitivity 47 %, specificity 86 %, χ 2 = 2.88, P = 0.089). Of the DWI readings 128 were true positive and 7 false negative (sensitivity 95 %, specificity 87 %, χ 2 = 70.67, P < 0.0001). Interobserver agreement was substantial for CT (χ= 0.72, 95 % confidence interval, 0.6-0.84) and DWI (χ= 0.82, 95 % confidence interval, 0.46-1). Taken together, detectability and detection rate of acute (< 6 h) hemisphere infarcts are significantly higher with DWI than with CT. (orig.)

  8. Differentiation of prostate cancer lesions in the Transition Zone by diffusion-weighted MRI

    Directory of Open Access Journals (Sweden)

    Jie Bao

    Full Text Available Objective: To differentiate prostate cancer lesions in transition zone by diffusion-weighted-MRI (DW-MRI. Methods: Data from a total of 63 patients who underwent preoperative DWI (b of 0–1000 s/mm2 were prospectively collected and processed by a monoexponential (DWI model and compared with a biexponential (IVIM model for quantitation of apparent diffusion coefficients (ADCs, perfusion fraction f, diffusivity D and pseudo-diffusivity D*. Histogram analyses were performed by outlining entire-tumor regions of interest (ROIs. These parameters (separately and combined in a logistic regression model were used to differentiate lesions depending on histopathological analysis of Magnetic Resonance/transrectal Ultrasound (MR/TRUS fusion-guided biopsy. The diagnostic ability of differentiate the PCa from BHP in TZ was analyzed by ROC regression. Histogram analysis of quantitative parameters and Gleason score were assessed with Spearman correlation. Results: Thirty (30 foci cases of PCa in PZ and 33 (36 foci cases of BPH were confirmed by pathology. Mean ADC, median ADC, 10th percentile ADC, 90th percentile ADC, kurtosis and skewness of ADC and mean D values, median D and 90th percentile D differed significantly between PCa and BHP in TZ. The highest classification accuracy was achieved by the mean ADC (0.841 and mean D (0.809. A logistic regression model based on mean ADC and mean D led to an AUC of 0.873, however, the difference is not significant. There were 7 Gleason 6 areas, 9 Gleason 7 areas, 8 Gleason 8 areas, 5 Gleason 9 areas and 2 Gleason 10 areas detected from the 31 prostate cancer areas, the mean Gleason value was(7.5 ± 1.2. The mean ADC and mean D had correlation with Gleason score(r = −0.522 and r = −0.407 respectively, P < 0.05. Conclusion: The diagnosis efficiency of IVIM parameters was not superior to ADC in the diagnosis of PCa in TZ. Moreover, the combination of mean ADC and mean D did not

  9. 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

  10. Feasibility of a RARE-based sequence for quantitative diffusion-weighted MRI of the spine

    International Nuclear Information System (INIS)

    Raya, J.G.; Dietrich, O.; Sommer, J.; Reiser, M.F.; Baur-Melnyk, A.; Birkenmaier, C.

    2007-01-01

    The feasibility of a diffusion-weighted single-shot fast-spin-echo sequence for the diagnostic work-up of bone marrow diseases was assessed. Twenty healthy controls and 16 patients with various bone marrow pathologies of the spine (bone marrow edema, tumor and inflammation) were examined with a diffusion-weighted single-shot sequence based on a modified rapid acquisition with relaxation enhancement (mRARE) technique; four diffusion weightings (b-values: 50, 250, 500 and 750 s/mm 2 ) in three orthogonal orientations were applied. Apparent diffusion coefficients (ADCs) were determined in the bone marrow and in the intervertebral discs of healthy volunteers and in diseased bone marrow. Ten of the 20 volunteers were repeatedly scanned within 30 min to examine short-time reproducibility. Spatial reproducibility was assessed by measuring ADCs in two different slices including the same lesion in 12 patients. The ADCs of the lesions exhibited significantly higher values, (1.27 ± 0.32) x 10 -3 mm 2 /s, compared with healthy bone marrow, (0.21 ± 0.10) x 10 -3 mm 2 /s. Short-time and spatial reproducibility had a mean coefficient of variation of 2.1% and 6.4%, respectively. The diffusion-weighted mRARE sequence provides a reliable tool for determining quantitative ADCs in vertebral bone marrow with adequate image quality. (orig.)

  11. Reversible changes in echo planar perfusion- and diffusion-weighted MRI in status epilepticus

    International Nuclear Information System (INIS)

    Flacke, S.; Keller, E.; Urbach, H.; Wuellner, U.; Hamzei, F.

    2000-01-01

    Perfusion imaging (PI) demonstrated increased perfusion and diffusion-weighted imaging (DWI) showed high signal limited to the left temporoparietal cortex in a 68-year-old man with nonconvulsive status epilepticus. The EEG showed a slow delta-wave focus. The patient recovered and PI, DWI and EEG changes completely resolved. (orig.)

  12. Reversible changes in echo planar perfusion- and diffusion-weighted MRI in status epilepticus

    Energy Technology Data Exchange (ETDEWEB)

    Flacke, S; Keller, E; Urbach, H [Dept. of Radiology, Univ. of Bonn (Germany); Wuellner, U; Hamzei, F [Dept. of Neurology, Univ. of Bonn (Germany)

    2000-02-01

    Perfusion imaging (PI) demonstrated increased perfusion and diffusion-weighted imaging (DWI) showed high signal limited to the left temporoparietal cortex in a 68-year-old man with nonconvulsive status epilepticus. The EEG showed a slow delta-wave focus. The patient recovered and PI, DWI and EEG changes completely resolved. (orig.)

  13. Contribution of the diffusion-weighted MRI in the diagnosis and follow-up of encephalopathy caused by maple syrup urine disease in a full-term newborn

    International Nuclear Information System (INIS)

    Ferraz-Filho, Jose Roberto Lopes; Floriano, Valdeci Helio; Quirici, Marcelo Bianco; Souza, Antonio Soares; Albuquerque, Regina Pires de

    2009-01-01

    The purpose of this case report is to show conventional MRI and diffusion-weighted imaging (DWI) findings of the different evolutionary phases in MSUD (Maple syrup urine disease) of a newborn that evolved with brain white matter lesions (author)

  14. 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

  15. Rapid resolution of diffusion weighted MRI abnormality in a patient with a stuttering stroke

    Science.gov (United States)

    Peters, Jurriaan M; MacLean, Ainsley V; Young, Geoffrey S

    2010-01-01

    We report the unusually rapid and spontaneous normalisation of low diffusivity that accompanied resolution of acute neurological deficits in a stroke patient who underwent two magnetic resonance imaging examinations within 24 h of symptom onset. Diffusion weighted imaging obtained within hours of onset of left sided weakness demonstrated a focal right capsular area of low diffusivity that resolved within 24 h, coinciding with resolution of the patient’s symptoms. PMID:22315635

  16. Cortical hypoxic-ischemic brain damage in shaken-baby (shaken impact) syndrome: value of diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Parizel, Paul M.; Oezsarlak, Oezkan; Goethem, Johan W. van; Ceulemans, Berten; Laridon, Annick; Jorens, Philippe G.

    2003-01-01

    Shaken-baby syndrome (SBS) is a type of child abuse caused by violent shaking of an infant, with or without impact, and characterized by subdural hematomas, retinal hemorrhages, and occult bone fractures. Parenchymal brain lesions in SBS may be missed or underestimated on CT scans, but can be detected at an earlier stage with diffusion-weighted MRI (DW-MRI) as areas of restricted diffusion. We demonstrate the value of DW-MRI in a 2-month-old baby boy with suspected SBS. The pattern of diffusion abnormalities indicates that the neuropathology of parenchymal lesions in SBS is due to hypoxic-ischemic brain injuries, and not to diffuse axonal injury. (orig.)

  17. Cortical hypoxic-ischemic brain damage in shaken-baby (shaken impact) syndrome: value of diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Parizel, Paul M.; Oezsarlak, Oezkan; Goethem, Johan W. van [Department of Radiology, University of Antwerp, Wilrijkstraat 10, 2650, Edegem (Belgium); Ceulemans, Berten; Laridon, Annick [Department of Pediatric Neurology, University of Antwerp, Wilrijkstraat 10, 2650, Edegem (Belgium); Jorens, Philippe G. [Department of Pediatric Intensive Care Medicine, University of Antwerp, Wilrijkstraat 10, 2650, Edegem (Belgium)

    2003-12-01

    Shaken-baby syndrome (SBS) is a type of child abuse caused by violent shaking of an infant, with or without impact, and characterized by subdural hematomas, retinal hemorrhages, and occult bone fractures. Parenchymal brain lesions in SBS may be missed or underestimated on CT scans, but can be detected at an earlier stage with diffusion-weighted MRI (DW-MRI) as areas of restricted diffusion. We demonstrate the value of DW-MRI in a 2-month-old baby boy with suspected SBS. The pattern of diffusion abnormalities indicates that the neuropathology of parenchymal lesions in SBS is due to hypoxic-ischemic brain injuries, and not to diffuse axonal injury. (orig.)

  18. Readout-segmented multi-shot diffusion-weighted MRI of the knee joint in patients with juvenile idiopathic arthritis.

    Science.gov (United States)

    Sauer, Alexander; Li, Mengxia; Holl-Wieden, Annette; Pabst, Thomas; Neubauer, Henning

    2017-10-12

    Diffusion-weighted MRI has been proposed as a new technique for imaging synovitis without intravenous contrast application. We investigated diagnostic utility of multi-shot readout-segmented diffusion-weighted MRI (multi-shot DWI) for synovial imaging of the knee joint in patients with juvenile idiopathic arthritis (JIA). Thirty-two consecutive patients with confirmed or suspected JIA (21 girls, median age 13 years) underwent routine 1.5 T MRI with contrast-enhanced T1w imaging (contrast-enhanced MRI) and with multi-shot DWI (RESOLVE, b-values 0-50 and 800 s/mm 2 ). Contrast-enhanced MRI, representing the diagnostic standard, and diffusion-weighted images at b = 800 s/mm 2 were separately rated by three independent blinded readers at different levels of expertise for the presence and the degree of synovitis on a modified 5-item Likert scale along with the level of subjective diagnostic confidence. Fourteen (44%) patients had active synovitis and joint effusion, nine (28%) patients showed mild synovial enhancement not qualifying for arthritis and another nine (28%) patients had no synovial signal alterations on contrast-enhanced imaging. Ratings by the 1st reader on contrast-enhanced MRI and on DWI showed substantial agreement (κ = 0.74). Inter-observer-agreement was high for diagnosing, or ruling out, active arthritis of the knee joint on contrast-enhanced MRI and on DWI, showing full agreement between 1st and 2nd reader and disagreement in one case (3%) between 1st and 3rd reader. In contrast, ratings in cases of absent vs. little synovial inflammation were markedly inconsistent on DWI. Diagnostic confidence was lower on DWI, compared to contrast-enhanced imaging. Multi-shot DWI of the knee joint is feasible in routine imaging and reliably diagnoses, or rules out, active arthritis of the knee joint in paediatric patients without the need of gadolinium-based i.v. contrast injection. Possibly due to "T2w shine-through" artifacts, DWI does not reliably

  19. Abnormal diffusion-weighted MRI in medulloblastoma: does it reflect small cell histology?

    International Nuclear Information System (INIS)

    Kotsenas, A.L.; Roth, T.C.; Manness, W.K.; Faerber, E.N.

    1999-01-01

    A 12-year-old boy presented with the classic CT and MRI findings of medulloblastoma and the unusual finding of increased signal on diffusion MRI. The small-cell histology of medulloblastoma may account for the increased signal seen on diffusion MRI. Diffusion MRI with echoplanar technique may be useful in evaluation of these tumors and metastatic disease. (orig.)

  20. Study on diffusion anisotropy of cerebral ischemia using diffusion weighted echo-planar MRI

    International Nuclear Information System (INIS)

    Kajima, Toshio

    1997-01-01

    Focal cerebral ischemia was produced by occlusion of the intracranial main cerebral artery with a silicone cylinder in Wistar rats. Diffusion-weighted echo-planar images (DW-EPls) using the motion-probing gradient (MPG) method were acquired at 1-3 hours and 24-48 hours after occlusion. Apparent diffusion coefficients (ADCs) were calculated from these images in ischemic lesions and in normal unoccluded regions. Results were as follows. Ischemic lesions could be detected on the DW-EPIs at 1 hour after occlusion. The ADC of water in the brain tissue was smaller than that of free water as a result of restricted diffusion. Anisotropic diffusion that probably can be attributed to the myelin sheath was observed in the normal white matter. In the ischemic lesions, the ADC decreased rapidly within 1-3 hours after occlusion and then decreased gradually after 24-48 hours. In the ischemic white matter, diffusion anisotropy disappeared at 24-48 hours after occlusion. Diffusion-weighted imaging may have applications in the examination of pathophysiological mechanisms in cerebral ischemia by means of evaluation of ADC and diffusion anisotropy. (author)

  1. Use of diffusion-weighted imaging (DWI) in PET/MRI for head and neck cancer evaluation

    International Nuclear Information System (INIS)

    Queiroz, Marcelo A.; Schulthess, Gustav von; Huellner, Martin; Kuhn, Felix; Veit-Haibach, Patrick; Huber, Gerhardt; Meerwein, Christian; Kollias, Spyros

    2014-01-01

    The purpose of this study was to analyze whether diffusion-weighted imaging (DWI) adds significant information to positron emission tomography/magnetic resonance imaging (PET/MRI) on lesion detection and characterization in head and neck cancers. Seventy patients with different head and neck cancers were enrolled in this prospective study. All patients underwent sequential contrast-enhanced (ce) PET/computed tomography (CT) and cePET/MRI using a tri-modality PET/CT-MR setup either for staging or re-staging. First, the DWI alone was evaluated, followed by the PET/MRI with conventional sequences, and in a third step, the PET/MRI with DWI was evaluated. McNemar's test was used to evaluate differences in the accuracy of PET/MRI with and without DWI compared to the standard of reference. One hundred eighty-eight (188) lesions were found, and of those, 118 (62.8 %) were malignant and 70 (37.2 %) were benign. PET/MRI without DWI had a higher accuracy in detecting malignant lesions than DWI alone (86.8 % vs. 60.6 %, p < 0.001). PET/MRI combined with DWI detected 120 concurrent lesions (89 malignant and 31 benign), PET/MRI alone identified 48 additional lesions (20 malignant and 28 benign), and DWI alone detected 20 different lesions (nine malignant and 11 benign). However, lesions detected on DWI did not change overall staging. SUV maximum and mean were significantly higher in malignant lesions than in benign lesions. DWI parameters between malignant and benign lesions were not statistically different. The use of DWI as part of PET/MRI to evaluate head and neck cancers does not provide remarkable information. Thus, the use of DWI might not be needed in clinical PET/MRI protocols for the staging or restaging of head and neck cancers. (orig.)

  2. 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

  3. Microstructural changes in ischemic cortical gray matter predicted by a model of diffusion-weighted MRI

    DEFF Research Database (Denmark)

    Vestergaard-Poulsen, Peter; Hansen, Brian; Østergaard, Leif

    2007-01-01

    compartment. A global optimum was found from a wide range of parameter permutations using cluster computing. We also present simulations of cell swelling and changes of exchange rate and intracellular diffusion as possible cellular mechanisms in ischemia. RESULTS: Our model estimates an extracellular volume...... compartments and slow water exchange. Our model reproduces the signal changes observed in ischemia via physiologically credible mechanisms. CONCLUSION: Our modeling suggests that transverse relaxation has a profound influence on the diffusion attenuated MR signal. Our simulations indicate cell swelling...... model to the diffusion-weighted MR signal obtained from cortical gray matter in healthy subjects. Our model includes variable volume fractions, intracellular restriction effects, and exchange between compartments in addition to individual diffusion coefficients and transverse relaxation rates for each...

  4. Liver Imaging Reporting and Data System on CT and gadoxetic acid-enhanced MRI with diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Dong Ik; Jang, Kyung Mi; Kim, Seong Hyun; Kang, Tae Wook; Song, Kyoung Doo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of)

    2017-10-15

    To assess major imaging features of Liver Imaging Reporting and Data System (LI-RADS) on contrast-enhanced CT and gadoxetic acid-enhanced MRI and to estimate whether the combination of signal intensity favouring HCC on hepatobiliary phase (HBP) and diffusion-weighted images (DWI) can act as a major feature in LI-RADS. Four hundred twenty one patients with 445 observations were included. Major features of LI-RADS on CT and MRI as well as HBP and DWI features were assessed. Diagnostic performances of LR-5 according to LI-RADS v2014 and modified LI-RADS which incorporate combination of HBP and DWI were assessed. Pairwise comparisons of the receiver operating characteristic (ROC) curves were performed. For HCCs, capsule appearance had the highest rate of discordance between CT and MRI (32.7%), followed by washout appearance (22.2%). Specificity (75%) of LR-5 of LI-RADS v2014 was lower than that (77.1-79.2%) of modified LI-RADS. Area under the ROC curve of modified LI-RADS (0.755-0.775) was not significantly different from that of LI-RADS v 2014 (0.709) (p > 0.05). There were substantial discordances between CT and MRI for capsule and washout appearances in hepatic observations, and combination of gadoxetic acid-enhanced MRI and DWI might be able to be incorporated as a major feature of LI-RADS. (orig.)

  5. Comparison of gadolinium-EOB-DTPA-enhanced and diffusion-weighted liver MRI for detection of small hepatic metastases.

    Science.gov (United States)

    Shimada, Kotaro; Isoda, Hiroyoshi; Hirokawa, Yuusuke; Arizono, Shigeki; Shibata, Toshiya; Togashi, Kaori

    2010-11-01

    To compare the accuracy of gadolinium ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI with that of diffusion-weighted MRI (DWI) in the detection of small hepatic metastases (2 cm or smaller). Forty-five patients underwent abdominal MRI at 3 T, including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), heavily T2WI (HASTE), DWI with a b-value of 500 s/mm(2) and contrast-enhanced MRI with Gd-EOB-DTPA. Two groups were assigned and compared: group A (T1WI, T2WI, HASTE and contrast-enhanced study with Gd-EOB-DTPA), and group B (T1WI, T2WI, HASTE and DWI). Two observers independently interpreted the images obtained in a random order. For all hepatic metastases, the diagnostic performance using each imaging set was evaluated by receiver-operating characteristic (ROC) curve analysis. A total of 51 hepatic metastases were confirmed. The area under the ROC curve (Az) of group A was larger than that of group B, and the difference in the mean Az values between the two image sets was statistically significant, whereas, there were three metastases that lay near thin vessels or among multiple cysts and were better visualised in group B than in group A. Gd-EOB-DTPA-enhanced MRI showed higher accuracy in the detection of small metastases than DWI.

  6. Diffusion-weighted MRI of denervated muscle: a clinical and experimental study

    International Nuclear Information System (INIS)

    Holl, Nathalie; Bierry, Guillaume; Moser, Thomas; Dietemann, Jean-Louis; Kremer, Stephane; Echaniz-Laguna, Andoni; Mohr, Michel; Loeffler, Jean-Philippe

    2008-01-01

    The aim of this study was to investigate skeletal muscle denervation using diffusion-weighted magnetic resonance imaging (DWMRI). Sciatic nerve axotomy was performed in a group of nine New Zealand White rabbits, and electromyographic (EMG), pathological, and DWMRI studies were conducted on ipsilateral hamstring muscles 1 and 8 days after axotomy. In addition, DWMRI studies were carried out on leg muscles of ten patients with acute and subacute lumbosacral radiculopathy. High intensity signals on short tau inversion recovery (STIR) magnetic resonance imaging and an increased apparent diffusion coefficient (ADC) were observed in denervated muscles of the animals 1 and 8 days after axotomy as well as in denervated muscles of the patients with radiculopathy. In the clinical study, ADC was 1.26±0.18 x 10 -9 m 2 /s in normal muscle and increased to 1.56±0.23 x 10 -9 m 2 /s in denervated muscles (p =0.0016). In animals, EMG and muscle pathological studies were normal 1 day after axotomy, and the muscles demonstrated spontaneous activity on EMG and neurogenic atrophy on histological studies 7 days later. This DWMRI study demonstrates that enlargement of extracellular fluid space in muscle denervation is an early phenomenon occurring several days before the appearance of EMG and histological abnormalities. (orig.)

  7. Silent ischemia after neuroprotected percutaneous carotid stenting: a diffusion-weighted MRI study.

    Science.gov (United States)

    Piñero, P; González, A; Mayol, A; Martínez, E; González-Marcos, J R; Boza, F; Cayuela, A; Gil-Peralta, A

    2006-01-01

    To assess by diffusion-weighted MR imaging (DWI) the efficacy of cerebral protection devices in avoiding embolization and new ischemic lesions in patients with severe internal carotid artery (ICA) stenosis undergoing carotid artery stent placement (CAS). One hundred sixty-two CASs in the extracranial ICA were performed with the use of distal filters. Mean age of the patients was 68.5 years (range, 33-86) and 122 patients (75.3%) were symptomatic. MR imaging was performed in all patients during the 3-day period before CAS, and DWI was obtained within 24 hours after the procedure. Ninety-five patients (58.6%) were monitored by transcranial Doppler ultrasonography for microemboli detection in the territory of the middle cerebral artery (MCA), ipsilateral to the vessel being treated. Twenty-eight patients (17.3%) showed 58 new ischemic foci in DWI, and 13 patients (46.4%) had multiple foci. Location of new lesions was mainly in the vascular territory supplied by the treated vessel (19 patients; 67.9%), but also in the contralateral MCA (1 patient; 3.6%), and the posterior fossa (4 patients; 14.3%). A significant relationship (P neuroprotected CAS. Appearance of new ischemic lesions were only significantly related to the occurrence of TIA but not to the number of MES registered or other variables. Despite the encouraging results, the incidence of new ischemic lesions should promote research for safer techniques and devices.

  8. Primary and metastatic ovarian cancer: Characterization by 3.0T diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lindgren, Auni [Kuopio University Hospital, Department of Gynaecology and Obstetrics, Kuopio (Finland); Anttila, Maarit [Kuopio University Hospital, Department of Gynaecology and Obstetrics, Kuopio (Finland); University of Eastern Finland, Institute of Clinical Medicine, School of Medicine, Gynaecology, Kuopio (Finland); Rautiainen, Suvi; Arponen, Otso; Haermae, Kirsi [Kuopio University Hospital, Department of Clinical Radiology, Kuopio (Finland); Kivelae, Annukka; Maekinen, Petri; Ylae-Herttuala, Seppo [University of Eastern Finland, Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, Kuopio (Finland); Haemaelaeinen, Kirsi [Kuopio University Hospital, Department of Pathology and Forensic Medicine, Kuopio (Finland); University of Eastern Finland, Institute of Clinical Medicine, School of Medicine, Pathology and Forensic Medicine, Kuopio (Finland); Kosma, Veli-Matti [Kuopio University Hospital, Department of Pathology and Forensic Medicine, Kuopio (Finland); University of Eastern Finland, Institute of Clinical Medicine, School of Medicine, Pathology and Forensic Medicine, Kuopio (Finland); University of Eastern Finland, Cancer Center of Eastern Finland, Kuopio (Finland); Vanninen, Ritva [Kuopio University Hospital, Department of Clinical Radiology, Kuopio (Finland); University of Eastern Finland, Cancer Center of Eastern Finland, Kuopio (Finland); University of Eastern Finland, Institute of Clinical Medicine, School of Medicine, Clinical Radiology, Kuopio (Finland); Sallinen, Hanna [Kuopio University Hospital, Department of Gynaecology and Obstetrics, Kuopio (Finland); University of Eastern Finland, Institute of Clinical Medicine, School of Medicine, Gynaecology, Kuopio (Finland); University of Eastern Finland, Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, Kuopio (Finland)

    2017-09-15

    We aimed to investigate whether apparent diffusion coefficients (ADCs) measured by 3.0T diffusion-weighted magnetic resonance imaging (DWI) associate with histological aggressiveness of ovarian cancer (OC) or predict the clinical outcome. This prospective study enrolled 40 patients with primary OC, treated 2011-2014. DWI was performed prior to surgery. Two observers used whole lesion single plane region of interest (WLsp-ROI) and five small ROIs (S-ROI) to analyze ADCs. Samples from tumours and metastases were collected during surgery. Immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to measure the expression of vascular endothelial growth factor (VEGF) and its receptors. The interobserver reliability of ADC measurements was excellent for primary tumours ICC 0.912 (WLsp-ROI). Low ADCs significantly associated with poorly differentiated OC (WLsp-ROI P = 0.035). In primary tumours, lower ADCs significantly associated with high Ki-67 (P = 0.001) and low VEGF (P = 0.001) expression. In metastases, lower ADCs (WLsp-ROI) significantly correlated with low VEGF receptors mRNA levels. ADCs had predictive value; 3-year overall survival was poorer in patients with lower ADCs (WLsp-ROI P = 0.023, S-ROI P = 0.038). Reduced ADCs are associated with histological severity and worse outcome in OC. ADCs measured with WLsp-ROI may serve as a prognostic biomarker of OC. (orig.)

  9. Primary and metastatic ovarian cancer: Characterization by 3.0T diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Lindgren, Auni; Anttila, Maarit; Rautiainen, Suvi; Arponen, Otso; Haermae, Kirsi; Kivelae, Annukka; Maekinen, Petri; Ylae-Herttuala, Seppo; Haemaelaeinen, Kirsi; Kosma, Veli-Matti; Vanninen, Ritva; Sallinen, Hanna

    2017-01-01

    We aimed to investigate whether apparent diffusion coefficients (ADCs) measured by 3.0T diffusion-weighted magnetic resonance imaging (DWI) associate with histological aggressiveness of ovarian cancer (OC) or predict the clinical outcome. This prospective study enrolled 40 patients with primary OC, treated 2011-2014. DWI was performed prior to surgery. Two observers used whole lesion single plane region of interest (WLsp-ROI) and five small ROIs (S-ROI) to analyze ADCs. Samples from tumours and metastases were collected during surgery. Immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to measure the expression of vascular endothelial growth factor (VEGF) and its receptors. The interobserver reliability of ADC measurements was excellent for primary tumours ICC 0.912 (WLsp-ROI). Low ADCs significantly associated with poorly differentiated OC (WLsp-ROI P = 0.035). In primary tumours, lower ADCs significantly associated with high Ki-67 (P = 0.001) and low VEGF (P = 0.001) expression. In metastases, lower ADCs (WLsp-ROI) significantly correlated with low VEGF receptors mRNA levels. ADCs had predictive value; 3-year overall survival was poorer in patients with lower ADCs (WLsp-ROI P = 0.023, S-ROI P = 0.038). Reduced ADCs are associated with histological severity and worse outcome in OC. ADCs measured with WLsp-ROI may serve as a prognostic biomarker of OC. (orig.)

  10. 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).

  11. 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)

  12. Microstructural changes in ischemic cortical gray matter predicted by a model of diffusion-weighted MRI.

    Science.gov (United States)

    Vestergaard-Poulsen, Peter; Hansen, Brian; Ostergaard, Leif; Jakobsen, Rikke

    2007-09-01

    To understand the diffusion attenuated MR signal from normal and ischemic brain tissue in order to extract structural and physiological information using mathematical modeling, taking into account the transverse relaxation rates in gray matter. We fit our diffusion model to the diffusion-weighted MR signal obtained from cortical gray matter in healthy subjects. Our model includes variable volume fractions, intracellular restriction effects, and exchange between compartments in addition to individual diffusion coefficients and transverse relaxation rates for each compartment. A global optimum was found from a wide range of parameter permutations using cluster computing. We also present simulations of cell swelling and changes of exchange rate and intracellular diffusion as possible cellular mechanisms in ischemia. Our model estimates an extracellular volume fraction of 0.19 in accordance with the accepted value from histology. The absolute apparent diffusion coefficient obtained from the model was similar to that of experiments. The model and the experimental results indicate significant differences in diffusion and transverse relaxation between the tissue compartments and slow water exchange. Our model reproduces the signal changes observed in ischemia via physiologically credible mechanisms. Our modeling suggests that transverse relaxation has a profound influence on the diffusion attenuated MR signal. Our simulations indicate cell swelling as the primary cause of the diffusion changes seen in the acute phase of brain ischemia. (c) 2007 Wiley-Liss, Inc.

  13. Gadoxetic acid-enhanced MRI and diffusion-weighted imaging for the detection of colorectal liver metastases after neoadjuvant chemotherapy

    International Nuclear Information System (INIS)

    Yu, Mi Hye; Lee, Jeong Min; Han, Joon Koo; Choi, Byung-Ihn; Hur, Bo Yun; Kim, Tae-You; Jeong, Seung-Yong; Yi, Nam-Joon; Suh, Kyung-Suk

    2015-01-01

    To investigate the diagnostic performance of gadoxetic acid-enhanced MRI including diffusion-weighted imaging (DWI) for the detection of colorectal liver metastases (CRLMs) after neoadjuvant chemotherapy (NAC). Our study population comprised 77 patients with 140 CRLMs who underwent gadoxetic acid-enhanced MRI within 1 month prior to surgery: group A (without NAC, n = 38) and group B (with NAC, n = 39). Two radiologists independently assessed all MR images and graded their diagnostic confidence for CRLM on a 5-point scale. Diagnostic accuracy, sensitivity and positive predictive values (PPV) were calculated and compared between the two groups. Diagnostic accuracy of gadoxetic acid-enhanced MRI in group B was slightly lower than in group A, but a statistically significant difference was not observed (observer 1: A z , 0.926 in group A, 0.905 in group B; observer 2: A z , 0.944 in group A, 0.885 in group B; p > 0.05). Sensitivity and PPV of group B were comparable to those of group A (observer 1: sensitivity = 93.5 % vs. 93.6 %, PPV = 95.1 % vs. 86.9 %; observer 2: sensitivity = 96.8 % vs. 91.0 %; PPV = 90.0 % vs. 89.7 %; all p > 0.05). Gadoxetic acid-enhanced MRI including DWI provided good diagnostic performance with high sensitivity (>90 %) for the detection of CRLMs, regardless of the influence of NAC. (orig.)

  14. Differentiation of prostate cancer lesions with high and with low Gleason score by diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Barbieri, Sebastiano; Broennimann, Michael; Vermathen, Peter; Thoeny, Harriet C. [Inselspital University Hospital, Institute of Diagnostic, Pediatric, and Interventional Radiology, Bern (Switzerland); Boxler, Silvan [Inselspital, Inselspital University Hospital, Department of Urology, Bern (Switzerland)

    2017-04-15

    To differentiate prostate cancer lesions with high and with low Gleason score by diffusion-weighted-MRI (DW-MRI). This prospective study was approved by the responsible ethics committee. DW-MRI of 84 consenting prostate and/or bladder cancer patients scheduled for radical prostatectomy were acquired and used to compute apparent diffusion coefficient (ADC), intravoxel incoherent motion (IVIM: the pure diffusion coefficient D{sub t}, the pseudo-diffusion fraction F{sub p} and the pseudo-diffusion coefficient D{sub p}), and high b value (as acquired and Hessian filtered) parameters within the index lesion. These parameters (separately and combined in a logistic regression model) were used to differentiate lesions depending on whether whole-prostate histopathological analysis after prostatectomy determined a high (≥7) or low (6) Gleason score. Mean ADC and D{sub t} differed significantly (p of independent two-sample t test < 0.01) between high- and low-grade lesions. The highest classification accuracy was achieved by the mean ADC (AUC 0.74) and D{sub t} (AUC 0.70). A logistic regression model based on mean ADC, mean F{sub p} and mean high b value image led to an AUC of 0.74 following leave-one-out cross-validation. Classification by IVIM parameters was not superior to classification by ADC. DW-MRI parameters correlated with Gleason score but did not provide sufficient information to classify individual patients. (orig.)

  15. Transient ischemic attacks and presence of an acute brain lesion in diffusion-weighted MRI: study of 50 patients

    Directory of Open Access Journals (Sweden)

    Sabeti M

    2012-10-01

    Full Text Available Background: Finding an acute brain lesion by diffusion-weighted (DW MRI upon an episode of transient ischemic attack (TIA is a predictor of imminent stroke in the near future. Therefore, exploring risk factors associated with lesions in DW-MRI of the brain is important in adopting an approach to TIA management. In the current study, we tried to determine the risk factors associated with lesions in DW-MRI of the brain in patients experiencing TIA episodes.Methods: Fifty patients with TIA were recruited consecutively in Sina Hospital, Tehran, Iran, over a 6-month period between July 2008 and January 2009. All of the patients underwent a complete neurological examination and laboratory tests. Brain DW-MRIs were performed for all the patients within 72 hours of a TIA episode.Results: DW-MRI revealed an acute lesion in 16% of the participants. There was a significant correlation between presence of an acute lesion in DW-MRI and TIA duration, history of diabetes mellitus and presence of unilateral facial palsy (P=0.0003, P=0.02 and P=0.008, respectively. Other variables such as age, hypertension, hyperlipidemia, past history of TIA, headache, vertigo, and sensory or visual disturbances had no significant relation with the presence of an acute lesion in DW-MRI.Conclusion: Duration of TIA, presence of diabetes mellitus and unilateral facial palsy are risk factors for an acute lesion in DW-MRI, meaning that patients with such risk factors are at risk for stroke in the near future.

  16. Differentiation between benign and malignant breast lesions using quantitative diffusion-weighted sequence on 3 T MRI

    International Nuclear Information System (INIS)

    Tan, S.L.L.; Rahmat, K.; Rozalli, F.I.; Mohd-Shah, M.N.; Aziz, Y.F.A.; Yip, C.H.; Vijayananthan, A.; Ng, K.H.

    2014-01-01

    Aim: To investigate the capability and diagnostic accuracy of diffusion-weighted imaging (DWI) in differentiating benign from malignant breast lesions using 3 T magnetic resonance imaging (MRI). Materials and methods: Women with suspicious or indeterminate breast lesions detected at MRI, mammogram and/or ultrasound were recruited for dynamic contrast-enhanced (DCE)-MRI and DWI prior to their biopsy. Image fusion of DCE-MRI with apparent diffusion coefficient (ADC) map was utilized to select the region of interest (ROI) for ADC calculation in the area that showed the most avid enhancement. DWI was performed using two sets of b-values at 500 and 1000 s/mm 2 , respectively. Results: Fifty women were recruited and the final analysis comprised 44 breast lesions, 31 of which were malignant and 13 were benign. Significant results were obtained between ADC values of benign and malignant lesions (p −3 mm 2 /s for b = 500 s/mm 2 and 1.22 × 10 −3 mm 2 /s for b = 1000 s/mm 2 , respectively. The sensitivity of DCE-MRI alone was 100% with a specificity of 66.7%. When DCE-MRI was combined with b = 1000 s/mm 2 , the specificity rose to 100%, while only mildly affecting sensitivity (90.6%). No significant correlation was found between ADC values and prognostic factors, such as lymph node metastasis, tumour size, oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status, and tumour grades. Conclusion: The present study provides consistent evidence to support DWI as a diagnostic tool for breast lesion characterization. A combination of DCE-MRI with DWI is suggested to improve the sensitivity and specificity of lesion characterization

  17. Novel Diffusion-Weighted MRI for High-Grade Prostate Cancer Detection

    Science.gov (United States)

    2017-10-01

    technical difficulty with comparison of radical prostatectomy histology with imaging, we have also introduced a method to evaluate the accuracy of our...MatLab code for co-registration of digital radical prostatectomy histology to T2 weighted MRI images of alpha and DDC maps to T2 weighted MRI was...HPA 479 ( Evaluation of Clinical Interventions), with a grade of A. He completed BHIS 509 (Informatics for the Clinical Investigator) with a grade

  18. The role of diffusion-weighted MRI (DWI) in the differentiation of benign from malignant skeletal lesions of the pelvis

    International Nuclear Information System (INIS)

    Douis, Hassan; Davies, Mark A.; Sian, Parmjit

    2016-01-01

    Purpose: To evaluate the utility of Diffusion-weighted MRI in the differentiation of benign from malignant skeletal lesions of the pelvis. Materials and methods: In this retrospective study 33 patients with indeterminate skeletal lesions of the pelvis were evaluated with DWI. Minimum, mean, maximum ADC-values of the skeletal lesions were measured followed by qualitative assessment of DWI. All patients underwent histological confirmation using CT-guided biopsy or surgical resection. The histology of the skeletal lesions was correlated with the findings on DWI. Results: There were 13 malignant lesions and 20 benign lesions. The mean, minimum and maximum ADC values (×10–6mm2/s) for benign skeletal lesions was higher than the mean ADC-values for malignant lesions (1422.2 vs 1263.7; 780.4 vs 771.8; 1969.6 vs 1676.8 respectively). These differences were however not statistically significant (P-values = 0.29; 0.94; 0.149 respectively). The sensitivity, specificity, positive predictive value and negative predictive value for qualitative assessment of Diffusion-weighted MRI in the differentiation of benign from malignant skeletal lesions were: 53.9%, 85%, 70%, 73.9% respectively. Qualitative assessment of DWI (restricted diffusion versus non-restricted diffusion) allowed differentiation of benign from malignant skeletal lesions (P-value = 0.0259). Conclusions: Qualitative assessment of DWI may aid in the differentiation of benign skeletal lesions from malignant skeletal lesions of the pelvis. Although DWI has a low sensitivity in the distinction of the two disease entities, it may be a useful adjunct due to its relatively high specificity. This is of particular importance in lymphoma where biopsy may only show chronic inflammatory cells and hence may be false negative.

  19. The role of diffusion-weighted MRI (DWI) in the differentiation of benign from malignant skeletal lesions of the pelvis

    Energy Technology Data Exchange (ETDEWEB)

    Douis, Hassan, E-mail: douis.hassan@hotmail.co.uk [Department of Radiology, University Hospital Birmingham NHS Foundation Trust, Birmingham, B15 2GW (United Kingdom); Department of Radiology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, B31 2AP (United Kingdom); Davies, Mark A. [Department of Radiology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, B31 2AP (United Kingdom); Sian, Parmjit [Department of Spinal Surgical Oncology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, B31 2AP (United Kingdom)

    2016-12-15

    Purpose: To evaluate the utility of Diffusion-weighted MRI in the differentiation of benign from malignant skeletal lesions of the pelvis. Materials and methods: In this retrospective study 33 patients with indeterminate skeletal lesions of the pelvis were evaluated with DWI. Minimum, mean, maximum ADC-values of the skeletal lesions were measured followed by qualitative assessment of DWI. All patients underwent histological confirmation using CT-guided biopsy or surgical resection. The histology of the skeletal lesions was correlated with the findings on DWI. Results: There were 13 malignant lesions and 20 benign lesions. The mean, minimum and maximum ADC values (×10–6mm2/s) for benign skeletal lesions was higher than the mean ADC-values for malignant lesions (1422.2 vs 1263.7; 780.4 vs 771.8; 1969.6 vs 1676.8 respectively). These differences were however not statistically significant (P-values = 0.29; 0.94; 0.149 respectively). The sensitivity, specificity, positive predictive value and negative predictive value for qualitative assessment of Diffusion-weighted MRI in the differentiation of benign from malignant skeletal lesions were: 53.9%, 85%, 70%, 73.9% respectively. Qualitative assessment of DWI (restricted diffusion versus non-restricted diffusion) allowed differentiation of benign from malignant skeletal lesions (P-value = 0.0259). Conclusions: Qualitative assessment of DWI may aid in the differentiation of benign skeletal lesions from malignant skeletal lesions of the pelvis. Although DWI has a low sensitivity in the distinction of the two disease entities, it may be a useful adjunct due to its relatively high specificity. This is of particular importance in lymphoma where biopsy may only show chronic inflammatory cells and hence may be false negative.

  20. Relationship between pretreatment FDG-PET and diffusion-weighted MRI biomarkers in diffuse large B-cell lymphoma

    Science.gov (United States)

    de Jong, Antoinette; Kwee, Thomas C; de Klerk, John MH; Adam, Judit A; de Keizer, Bart; Fijnheer, Rob; Kersten, Marie José; Ludwig, Inge; Jauw, Yvonne WS; Zijlstra, Josée M; den Bos, Indra C Pieters - Van; Stoker, Jaap; Hoekstra, Otto S; Nievelstein, Rutger AJ

    2014-01-01

    The purpose of this study was to determine the correlation between the 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) standardized uptake value (SUV) and the diffusion-weighted magnetic resonance imaging (MRI) apparent diffusion coefficient (ADC) in newly diagnosed diffuse large B-cell lymphoma (DLBCL). Pretreatment FDG-PET and diffusion-weighted MRI of 21 patients with histologically proven DLBCL were prospectively analyzed. In each patient, maximum, mean and peak standardized uptake value (SUV) was measured in the lesion with visually highest FDG uptake and in the largest lesion. Mean ADC (ADCmean, calculated with b-values of 0 and 1000 s/mm2) was measured in the same lesions. Correlations between FDG-PET metrics (SUVmax, SUVmean, SUVpeak) and ADCmean were assessed using Pearson’s correlation coefficients. In the lesions with visually highest FDG uptake, no significant correlations were found between the SUVmax, SUVmean, SUVpeak and the ADCmean (P=0.498, P=0.609 and P=0.595, respectively). In the largest lesions, there were no significant correlations either between the SUVmax, SUVmean, SUVpeak and the ADCmean (P=0.992, P=0.843 and P=0.894, respectively). The results of this study indicate that the glycolytic rate as measured by FDG-PET and changes in water compartmentalization and water diffusion as measured by the ADC are independent biological phenomena in newly diagnosed DLBCL. Further studies are warranted to assess the complementary roles of these different imaging biomarkers in the evaluation and follow-up of DLBCL. PMID:24795837

  1. Analysis of acute ischemic stroke presenting classic lacunar syndrome. A study by diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Terai, Satoshi; Ota, Kazuki; Tamaki, Kinya [Hakujyuji Hospital, Fukuoka (Japan)

    2002-03-01

    We retrospectively assessed the pathophysiological features of acute ischemic stroke presenting ''classic'' lacunar syndrome by using diffusion-weighted imaging (DWI). Subjects were 16 patients who were admitted to our hospital within 24 hours of stroke onset and underwent DWI examination on admission. These were divided into three categorical groups; pure motor hemiplegia (PMH) in 8, sensorimotor stroke (SMS) in 7, and dysarthria-clumsy hand syndrome (DCHS) in 1. The fresh responsible lesions were identified by DWI in the perforating territory in 7 patients with PMH and 7 with SMS. Four (one had two possible response lesions; pons and corona radiata) and five patients in the respective groups were diagnosed as lacunar infarction on admission (the largest dimension of the lesion measuring smaller than 15 mm). On the contralateral side to the neurological symptoms, DWI revealed high intensities in cortex, subcortical white matter, and anterior and posterior border zones in the remaining one patient with PMH and in the precentral arterial region in one with DCHS. They were diagnosed as atherothrombotic infarction resulting from the occlusion of the internal carotid artery and cerebral embolism due to atrial fibrillation, respectively. Three patients with PMH showed progressive deterioration after admission and follow-up DWI study in an acute stage revealed enlargement of heir ischemic lesions. The present study suggests that DWI is a useful imaging technique for diagnosis of clinical categories and observation for pathophsiological alteration in the acute ischemic stroke patients with ''classic'' lacunar syndrome. Our results also indicate a necessity to be aware that various types of fresh ischemic lesions other than a single lacune might possibly be developing in cases with this syndrome. (author)

  2. MRI-only lesions: application of diffusion-weighted imaging obviates unnecessary MR-guided breast biopsies

    Energy Technology Data Exchange (ETDEWEB)

    Spick, Claudio; Pinker-Domenig, Katja; Helbich, Thomas H.; Baltzer, Pascal A. [Medical University of Vienna (AKH), General Hospital Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Wien (Austria); Rudas, Margaretha [Medical University of Vienna (AKH), Clinical Institute of Pathology, Wien (Austria)

    2014-06-15

    To assess if the application of diffusion-weighted imaging (DWI) obviates unnecessary MR-guided biopsies in suspicious breast lesions visible only on contrast-enhanced MRI (CE-MRI). This institutional review board (IRB)-approved, retrospective, single-centre study included 101 patients (mean age, 49.5; SD 13.9 years) who underwent additional DWI at 1.5 T prior to MRI-guided biopsy of 104 lesions classified as suspicious for malignancy and visible on CE-MRI only. An experienced radiologist, blinded to histopathologic and follow-up results, measured apparent diffusion coefficient (ADC) values obtained from DWI. Diagnostic accuracy was investigated using receiver operating characteristics (ROC) analysis. Histopathology revealed 20 malignant and 84 benign lesions. Lesions were masses in 61 (15 malignant, 24.6 %) and non-masses in 43 cases (five malignant, 11.6 %). Mean ADC values were 1.53 ± 0.38 x 10{sup -3} mm{sup 2}/s in benign lesions and 1.06 ± 0.27 x 10{sup -3} mm{sup 2}/s in malignant lesions. ROC analysis revealed exclusively benign lesions if ADC values were greater than 1.58 x 10{sup -3} mm{sup 2}/s. As a consequence, 29 false-positive biopsies (34.5 %) could have been avoided without any false-negative findings. Both in mass and in non-mass lesions, rule-in and rule-out criteria were identified using flexible ADC thresholds based on ROC analysis. Additional application of DWI in breast lesions visible only on MRI can avoid false-positive, MR-guided biopsies. Thus, DWI should be an integral part of breast MRI protocols. (orig.)

  3. Role of diffusion-weighted MRI in differentiation of hepatic abscesses from non-infected fluid collections.

    Science.gov (United States)

    Schmid-Tannwald, C; Schmid-Tannwald, C M; Morelli, J N; Neumann, R; Reiser, M F; Nikolaou, K; Rist, C

    2014-07-01

    To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the differentiation of hepatic abscesses from non-infected fluid collections. In this retrospective study, 22 hepatic abscesses and 27 non-infected hepatic fluid collections were examined in 27 patients who underwent abdominal MRI including DW-MRI. Two independent observers reviewed T2-weighted + DW-MRI and T2-weighted + contrast-enhanced T1-weighted (CET1W) images in two sessions. Detection rates and confidence levels were calculated and compared using McNemar's and Wilcoxon's signed rank tests, respectively. Apparent diffusion coefficient (ADC) values of abscesses and non-infected fluid collections were compared using the t-test. Receiver operating characteristic (ROC) curves were constructed. There was no statistically significant difference in the accuracy of detecting abscesses using T2-weighted + DW-MRI (both observers: 21/22, 95.5%) versus T2-weighted + CET1W images (observer 1: 21/22, 95.5%; observer 2: 22/22, 100%; p collections (0.83 ± 0.24 versus 2.25 ± 0.61 × 10(-3) mm(2)/s; p collections at a threshold ADC value of 1.36 × 10(-3) mm(2)/s. DW-MRI allows qualitative and quantitative differentiation of abscesses from non-infected fluid collections in the liver. Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  4. Separation of type and grade in cervical tumours using non-mono-exponential models of diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Winfield, Jessica M.; Collins, David J.; Morgan, Veronica A.; DeSouza, Nandita M.; Orton, Matthew R.; Ind, Thomas E.J.; Attygalle, Ayoma; Hazell, Steve

    2017-01-01

    Assessment of empirical diffusion-weighted MRI (DW-MRI) models in cervical tumours to investigate whether fitted parameters distinguish between types and grades of tumours. Forty-two patients (24 squamous cell carcinomas, 14 well/moderately differentiated, 10 poorly differentiated; 15 adenocarcinomas, 13 well/moderately differentiated, two poorly differentiated; three rare types) were imaged at 3 T using nine b-values (0 to 800 s mm -2 ). Mono-exponential, stretched exponential, kurtosis, statistical, and bi-exponential models were fitted. Model preference was assessed using Bayesian Information Criterion analysis. Differences in fitted parameters between tumour types/grades and correlation between fitted parameters were assessed using two-way analysis of variance and Pearson's linear correlation coefficient, respectively. Non-mono-exponential models were preferred by 83 % of tumours with bi-exponential and stretched exponential models preferred by the largest numbers of tumours. Apparent diffusion coefficient (ADC) and diffusion coefficients from non-mono-exponential models were significantly lower in poorly differentiated tumours than well/moderately differentiated tumours. α (stretched exponential), K (kurtosis), f and D* (bi-exponential) were significantly different between tumour types. Strong correlation was observed between ADC and diffusion coefficients from other models. Non-mono-exponential models were preferred to the mono-exponential model in DW-MRI data from cervical tumours. Parameters of non-mono-exponential models showed significant differences between types and grades of tumours. (orig.)

  5. Separation of type and grade in cervical tumours using non-mono-exponential models of diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Winfield, Jessica M.; Collins, David J.; Morgan, Veronica A.; DeSouza, Nandita M. [The Royal Marsden NHS Foundation Trust, MRI Unit, Sutton, Surrey (United Kingdom); The Institute of Cancer Research, Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, London (United Kingdom); Orton, Matthew R. [The Institute of Cancer Research, Cancer Research UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, London (United Kingdom); Ind, Thomas E.J. [The Royal Marsden NHS Foundation Trust, Gynaecology Unit, London (United Kingdom); Attygalle, Ayoma; Hazell, Steve [The Royal Marsden NHS Foundation Trust, Department of Histopathology, London (United Kingdom)

    2017-02-15

    Assessment of empirical diffusion-weighted MRI (DW-MRI) models in cervical tumours to investigate whether fitted parameters distinguish between types and grades of tumours. Forty-two patients (24 squamous cell carcinomas, 14 well/moderately differentiated, 10 poorly differentiated; 15 adenocarcinomas, 13 well/moderately differentiated, two poorly differentiated; three rare types) were imaged at 3 T using nine b-values (0 to 800 s mm{sup -2}). Mono-exponential, stretched exponential, kurtosis, statistical, and bi-exponential models were fitted. Model preference was assessed using Bayesian Information Criterion analysis. Differences in fitted parameters between tumour types/grades and correlation between fitted parameters were assessed using two-way analysis of variance and Pearson's linear correlation coefficient, respectively. Non-mono-exponential models were preferred by 83 % of tumours with bi-exponential and stretched exponential models preferred by the largest numbers of tumours. Apparent diffusion coefficient (ADC) and diffusion coefficients from non-mono-exponential models were significantly lower in poorly differentiated tumours than well/moderately differentiated tumours. α (stretched exponential), K (kurtosis), f and D* (bi-exponential) were significantly different between tumour types. Strong correlation was observed between ADC and diffusion coefficients from other models. Non-mono-exponential models were preferred to the mono-exponential model in DW-MRI data from cervical tumours. Parameters of non-mono-exponential models showed significant differences between types and grades of tumours. (orig.)

  6. Ultrasound elastography and diffusion weighted MRI in patients with rectal cancer

    DEFF Research Database (Denmark)

    Rafaelsen, Søren Rafael; Vagn-Hansen, Chris Aksel; Sørensen, Torben

    the Acoustic Radiation Force Impulse (ARFI) to generate information on the mechanical properties of the tissue. The objective quantitative elastography shear wave velocity was blindly compared to the ADC measurements using a 1.5 Tesla MRI system. The study was approved by the local Clinical Ethics Committee...

  7. Differentiation of benign and malignant skeletal lesions with quantitative diffusion weighted MRI at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Ahlawat, Shivani, E-mail: sahlawa1@jhmi.edu [The Russell H. Morgan Department of Radiology & Radiological Science, The Johns Hopkins University School of Medicine, 601 North Wolfe Street, Baltimore MD 21287 (United States); Khandheria, Paras, E-mail: pkhandh1@jhmi.edu [The Russell H. Morgan Department of Radiology & Radiological Science, The Johns Hopkins University School of Medicine, 601 North Wolfe Street, Baltimore MD 21287 (United States); Subhawong, Ty K., E-mail: TSubhawong@med.miami.edu [Department of Radiology (R-109), University of Miami Leonard M. Miller Miami, FL 33101 (United States); Fayad, Laura M., E-mail: lfayad1@jhmi.edu [The Russell H. Morgan Department of Radiology & Radiological Science, The Johns Hopkins University School of Medicine, 601 North Wolfe Street, Baltimore MD 21287 (United States)

    2015-06-15

    Highlights: • DWI may have predictive value for the characterization of bone lesions. • Benign lesions have higher minimum, and mean ADC values than malignancies. • Minimum ADC has the highest accuracy in discerning benign from malignant lesion. • Minimum ADC of 0.9 × 10. • All ADC measurements were made with high inter-observer concordance. - Abstract: Objectives: To investigate the accuracy of quantitative diffusion-weighted imaging with apparent diffusion coefficient (ADC) mapping for characterizing bone lesions as benign or malignant. Methods: At 3 T, 31 subjects with intramedullary lesions imaged by DWI (b-values 50, 400, 800 s/mm{sup 2}) were included. ADC values (minimum, mean, maximum) were recorded by three observers independently. Interobserver variability and differences between ADC values in benign and malignant lesions were assessed (unpaired t-test, receiver operating characteristic (ROC) analysis). Results: Of 31 lesions, 18 were benign (osteoblastic (n = 1), chondroid (n = 6), cysts (n = 4), hemangiomatosis (n = 1), fibrous (n = 3), eosinophilic granuloma (n = 1), giant cell tumor (n = 1), osteomyelitis (n = 1)) and 13 were malignant (primary (n = 5), metastases (n = 8)). Overall, there were higher minimum (1.27 × 10{sup −3} mm{sup 2}/s vs 0.68 × 10{sup −3} mm{sup 2}/s, p < 0.001), mean (1.68 × 10{sup −3} mm{sup 2}/s vs 1.13 × 10{sup −3} mm{sup 2}/s, p < 0.001), and maximum (2.09 × 10{sup −3} mm{sup 2}/s vs 1. 7 × 10{sup −3} mm{sup 2}/s, p = 0.03). ADC values in benign lesions compared with those in malignancies. ROC analysis revealed areas under the curve for minimum, mean, and maximum ADC values of 0.91, 0.85, and 0.71, respectively. ADC measurements were made with high inter-observer concordance (ρ = 0.83–0.96). Conclusion: Quantitative ADC maps may have predictive value for the characterization of bone lesions. Benign lesions generally have higher minimum, mean, and maximum ADC values than malignancies, with the

  8. Whole body MRI, including diffusion-weighted imaging in follow-up of patients with testicular cancer.

    Science.gov (United States)

    Mosavi, Firas; Laurell, Anna; Ahlström, Håkan

    2015-11-01

    Whole body (WB) magnetic resonance imaging (MRI), including diffusion-weighted imaging (DWI) has become increasingly utilized in cancer imaging, yet the clinical utility of these techniques in follow-up of testicular cancer patients has not been evaluated. The purpose of this study was to evaluate the feasibility of WB MRI with continuous table movement (CTM) technique, including multistep DWI in follow-up of patients with testicular cancer. WB MRI including DWI was performed in follow-up of 71 consecutive patients (median age, 37 years; range 19-84) with histologically confirmed testicular cancer. WB MRI protocol included axial T1-Dixon and T2-BLADE sequences using CTM technique. Furthermore, multi-step DWI was performed using b-value 50 and 1000 s/mm(2). One criterion for feasibility was patient tolerance and satisfactory image quality. Another criterion was the accuracy in detection of any pathological mass, compared to standard of reference. Signal intensity in DWI was used for evaluation of residual mass activity. Clinical, laboratory and imaging follow-up were applied as standard of reference for the evaluation of WB MRI. WB MRI was tolerated in nearly all patients (69/71 patients, 97%) and the image quality was satisfactory. Metal artifacts deteriorated the image quality in six patients, but it did not influence the overall results. No case of clinical relapse was observed during the follow-up time. There was a good agreement between conventional WB MRI and standard of reference in all patients. Three patients showed residual masses and DWI signal was not restricted in these patients. Furthermore, DWI showed abnormally high signal intensity in a normal-sized retroperitoneal lymph node indicating metastasis. The subsequent (18)F-FDG PET/CT could verify the finding. WB MRI with CTM technique including multi-step DWI is feasible in follow-up of patients with testicular cancer. DWI may contribute to important added-value data to conventional MRI sequences

  9. 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.

  10. 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

  11. Redefining the target early during treatment. Can we visualize regional differences within the target volume using sequential diffusion weighted MRI?

    International Nuclear Information System (INIS)

    Lambrecht, Maarten; Van Herck, Hans; De Keyzer, Frederik; Vandecaveye, Vincent; Slagmolen, Pieter; Suetens, Paul; Hermans, Robert; Nuyts, Sandra

    2014-01-01

    Purpose: In head and neck cancer, diffusion weighted MRI (DWI) can predict response early during treatment. Treatment-induced changes and DWI-specific artifacts hinder an accurate registration between apparent diffusion coefficient (ADC) maps. The aim of the study was to develop a registration tool which calculates and visualizes regional changes in ADC. Methods: Twenty patients with stage IV HNC treated with primary radiotherapy received an MRI including DWI before and early during treatment. Markers were manually placed at anatomical landmarks on the different modalities at both time points. A registration method, consisting of a fully automatic rigid and nonrigid registration and two semi-automatic thin-plate spline (TPS) warps was developed and applied to the image sets. After each registration step the mean registration errors were calculated and ΔADC was compared between good and poor responders. Results: Adding the TPS warps significantly reduced the registration error (in mm, 6.3 ± 6.2 vs 3.2 ± 3.3 mm, p < 0.001). After the marker based registration the median ΔADC in poor responders was significantly lower than in good responders (7% vs. 21%; p < 0.001). Conclusions: This registration method allowed for a significant reduction of the mean registration error. Furthermore the voxel-wise calculation of the ΔADC early during radiotherapy allowed for a visualization of the regional differences of ΔADC within the tumor

  12. Case report of a young stroke patient showing interim normalization of the MRI diffusion-weighted imaging lesion

    International Nuclear Information System (INIS)

    Ostwaldt, Ann-Christin; Usnich, Tatiana; Nolte, Christian H.; Villringer, Kersten; Fiebach, Jochen B.

    2015-01-01

    In acute ischemic stroke, diffusion weighted imaging (DWI) shows hyperintensities and is considered to indicate irreversibly damaged tissue. We present the case of a young stroke patient with unusual variability in the development of signal intensities within the same vessel territory. A 35-year-old patient presented with symptoms of global aphasia and hypesthesia of the left hand. MRI demonstrated a scattered lesion in the MCA territory. After rtPA therapy the patient received further MRI examination, three times on day 1, and once on day 2, 3, 5 and 43. The posterior part of the lesion showed the usual pattern with increasing DWI hyperintensity and decreased ADC, as well as delayed FLAIR positivity. However, the anterior part of the lesion, which was clearly visible in the first examination completely normalized on the first day and only reappeared on day 2. This was accompanied by a normalization of the ADC as well as an even further delayed FLAIR positivity. We showed that interim normalization of DWI and ADC in the acute phase can not only be found in rodent models of stroke, but also in humans. We propose that DWI lesion development might be more variable during the first 24 h after stroke than previously assumed

  13. Pretreatment Diffusion-Weighted MRI Can Predict the Response to Neoadjuvant Chemotherapy in Patients with Nasopharyngeal Carcinoma

    Directory of Open Access Journals (Sweden)

    Guo-Yi Zhang

    2015-01-01

    Full Text Available Purpose. To explore the potential of diffusion-weighted (DW magnetic resonance imaging (MRI using apparent diffusion coefficient (ADC for predicting the response to neoadjuvant chemotherapy in nasopharyngeal carcinoma (NPC. Methods and Materials. Ninety-two consecutive patients with NPC who underwent three cycles of neoadjuvant chemotherapy were retrospectively analyzed. DW and anatomical MRI were performed before and after neoadjuvant chemotherapy prior to radiotherapy. Pretreatment ADCs and percentage increases in ADC after chemotherapy were calculated for the primary lesions and metastatic adenopathies. Receiver operating characteristic curve analysis was used to select optimal pretreatment ADCs. Results. Pretreatment mean ADCs were significantly lower for responders than for nonresponders (primary lesions, P=0.012; metastatic adenopathies, P=0.013. Mean percentage increases in ADC were higher for responders than for nonresponders (primary lesions, P=0.008; metastatic adenopathies, P<0.001. The optimal pretreatment primary lesion and metastatic adenopathy ADCs for differentiating responders from nonresponders were 0.897 × 10−3 mm2/sec and 1.031 × 10−3 mm2/sec, respectively. Conclusions. NPC patients with low pretreatment ADCs tend to respond better to neoadjuvant chemotherapy. Pretreatment ADCs could be used as a new pretreatment imaging biomarker of response to neoadjuvant chemotherapy.

  14. Diffusion-weighted MRI to assess response to chemoradiotherapy in rectal cancer: main interpretation pitfalls and their use for teaching

    Energy Technology Data Exchange (ETDEWEB)

    Lambregts, Doenja M.J.; Lahaye, Max J.; Maas, Monique [The Netherlands Cancer Institute, Department of Radiology, Amsterdam (Netherlands); Heeswijk, Miriam M. van [The Netherlands Cancer Institute, Department of Radiology, Amsterdam (Netherlands); Maastricht University Medical Centre, Department of Radiology, Maastricht (Netherlands); Maastricht University Medical Centre, Department of Surgery, Maastricht (Netherlands); Maastricht University, GROW School for Oncology and Developmental Biology, Maastricht (Netherlands); Delli Pizzi, Andrea [Gabriele d' Annunzio University, SS. Annunziate Hospital, Department of Neuroscience and Imaging, Chieti (Italy); Elderen, Saskia G.C. van [Leiden University Medical Centre, Department of Radiology, Leiden (Netherlands); Andrade, Luisa [Hospitais da Universidade de Coimbra, Department of Radiology, Coimbra (Portugal); Peters, Nicky H.G.M.; Osinga-de Jong, Margreet [Zuyderland Medical Center, location Heerlen, Heerlen (Netherlands); Kint, Peter A.M. [Amphia Hospital, Department of Radiology, Breda (Netherlands); Bipat, Shandra [Academic Medical Centre, Department of Radiology, Amsterdam (Netherlands); Ooms, Rik [Maxima Medical Centre, Department of Radiology, Eindhoven-Veldhoven (Netherlands); Beets, Geerard L. [The Netherlands Cancer Institute, Department of Surgery, Amsterdam (Netherlands); Maastricht University, GROW School for Oncology and Developmental Biology, Maastricht (Netherlands); Bakers, Frans C.H. [Maastricht University Medical Centre, Department of Radiology, Maastricht (Netherlands); Beets-Tan, Regina G.H. [The Netherlands Cancer Institute, Department of Radiology, Amsterdam (Netherlands); Maastricht University, GROW School for Oncology and Developmental Biology, Maastricht (Netherlands)

    2017-10-15

    To establish the most common image interpretation pitfalls for non-expert readers using diffusion-weighted imaging (DWI) to assess response to chemoradiotherapy in patients with rectal cancer and to explore the use of these pitfalls in an expert teaching setting. Two independent non-expert readers (R1 and R2) scored the restaging DW MRI scans (b1,000 DWI, in conjunction with ADC maps and T2-W MRI scans for anatomical reference) in 100 patients for the likelihood of a complete response versus residual tumour using a five-point confidence score. The readers received expert feedback and the final response outcome for each case. The supervising expert documented any potential interpretation errors/pitfalls discussed for each case to identify the most common pitfalls. The most common pitfalls were the interpretation of low signal on the ADC map, small susceptibility artefacts, T2 shine-through effects, suboptimal sequence angulation and collapsed rectal wall. Diagnostic performance (area under the ROC curve) was 0.78 (R1) and 0.77 (R2) in the first 50 patients and 0.85 (R1) and 0.85 (R2) in the final 50 patients. Five main image interpretation pitfalls were identified and used for teaching and feedback. Both readers achieved a good diagnostic performance with an AUC of 0.85. (orig.)

  15. Diffusion-weighted MRI to assess response to chemoradiotherapy in rectal cancer: main interpretation pitfalls and their use for teaching

    International Nuclear Information System (INIS)

    Lambregts, Doenja M.J.; Lahaye, Max J.; Maas, Monique; Heeswijk, Miriam M. van; Delli Pizzi, Andrea; Elderen, Saskia G.C. van; Andrade, Luisa; Peters, Nicky H.G.M.; Osinga-de Jong, Margreet; Kint, Peter A.M.; Bipat, Shandra; Ooms, Rik; Beets, Geerard L.; Bakers, Frans C.H.; Beets-Tan, Regina G.H.

    2017-01-01

    To establish the most common image interpretation pitfalls for non-expert readers using diffusion-weighted imaging (DWI) to assess response to chemoradiotherapy in patients with rectal cancer and to explore the use of these pitfalls in an expert teaching setting. Two independent non-expert readers (R1 and R2) scored the restaging DW MRI scans (b1,000 DWI, in conjunction with ADC maps and T2-W MRI scans for anatomical reference) in 100 patients for the likelihood of a complete response versus residual tumour using a five-point confidence score. The readers received expert feedback and the final response outcome for each case. The supervising expert documented any potential interpretation errors/pitfalls discussed for each case to identify the most common pitfalls. The most common pitfalls were the interpretation of low signal on the ADC map, small susceptibility artefacts, T2 shine-through effects, suboptimal sequence angulation and collapsed rectal wall. Diagnostic performance (area under the ROC curve) was 0.78 (R1) and 0.77 (R2) in the first 50 patients and 0.85 (R1) and 0.85 (R2) in the final 50 patients. Five main image interpretation pitfalls were identified and used for teaching and feedback. Both readers achieved a good diagnostic performance with an AUC of 0.85. (orig.)

  16. Role of diffusion-weighted echo-planar MRI in distinguishing between brain abscess and tumour: a preliminary report

    International Nuclear Information System (INIS)

    Noguchi, K.; Watanabe, N.; Nagayoshi, T.; Kanazawa, T.; Toyoshima, S.; Shimizu, M.; Seto, H.

    1999-01-01

    Our purpose was to evaluate diffusion-weighted (DW) echo-planar MRI in differentiating between brain abscess and tumour. We examined two patients with surgically confirmed pyogenic brain abscess and 18 with metastatic brain tumours or high-grade glioma, using a 1.5 T system. The apparent diffusion coefficient (ADC) of each necrotic or solid contrast-enhancing lesion was measured with two different b values (20 and 1200 s/mm 2 ). All capsule-stage brain abscesses (4 lesions) and zones of cerebritis (2 lesions) were identified on high-b-value DWI as markedly high-signal areas of decreased ADC (range, 0.58-0.70 [(10-3 mm 2 /s; mean, 0.63)]). All cystic or necrotic portions of brain tumours (14 lesions) were identified on high-b-value DWI as low-signal areas of increased ADC (range, 2.20-3.20 [(10-3 mm 2 /s; mean, 2.70)]). Solid, contrast-enhancing portions of brain tumours (19 lesions) were identified on high-b-value DWI as high-signal areas of sightly decreased or increased ADC (range, 0.77-1.29 [(10-3 mm 2 /s; mean, 0.94)]). Our preliminary results indicate that DW echo-planar MRI be used for distinguishing between brain abscess and tumour. (orig.) (orig.)

  17. Comparative study of diffusion weighted imaging and dynamic contrast enhanced MRI for the detection of small breast cancers

    International Nuclear Information System (INIS)

    Tang Jianhua; Yan Fuhua; Zhou Meiling; Ye Fang; Xu Pengju

    2008-01-01

    Objective: To compare the sensitivity of diffusion weighted imaging (DWI) with dynamic contrast enhanced (DCE) MRI for the detection of small breast cancers and to evaluate the clinical value of DWI. Methods: Forty-eight patients with benign (n=25) and malignant (n=45) small breast lesions (≤2 cm) proved by pathology underwent DWI and DCE MRI. The DCE MRI was performed using FLASH sequence and the time-signal intensity curve was drawn. The DWI was performed using GRAPPA- EPI sequence with different b values (800, 1000 s/mm 2 ) and the ADC values of lesions were measured. The sensitivity and specificity of DWI for the detection of small breast cancers were compared with DCE MRI. Results: Forty of 45 small breast cancers and 19 of 25 small benign breast lesions were correctly diagnosed using DCE MRI. The sensitivity and positive predictive value of TIC were 88.9% (40/45) and 87.0% (40/46). With b values of 800 s/mm 2 and 1000 s/mm 2 , the average ADC values of small breast cancers were (1.153±0.192) x 10 -3 and (1.079±0.186) x 10 -3 mm 2 /s, while those of benign ones were (1.473±0.252) x 10 -3 and (1.419 ± 0.255) x 10 -3 mm 2 /s, respectively. There was no significant difference for the ADC values with different b values in the same group (P>0.05), while there was a significant difference between the malignant and the benign lesions (P 2 . Both the sensitivity and positive predictive value of diagnosis were 86.7% (39/45). The abilities of DWI and DCE MRI for the diagnosis of small breast cancers were the same. The sensitivity (93.3%) and positive predictive value (91.3%) were improved with the combination of DCE MRI and DWI. Conclusion: DWI has a high sensitivity for the detection of small breast cancers, the ADC value can provide valuable information in the differential diagnosis. (authors)

  18. Added value of diffusion-weighted MRI in detection of cervical cancer recurrence: comparison with morphologic and dynamic contrast-enhanced MRI sequences.

    Science.gov (United States)

    Lucas, Rita; Lopes Dias, João; Cunha, Teresa Margarida

    2015-01-01

    We aimed to evaluate the added value of diffusion-weighted imaging (DWI) to standard magnetic resonance imaging (MRI) for detecting post-treatment cervical cancer recurrence. The detection accuracy of T2-weighted (T2W) images was compared with that of T2W MRI combined with either dynamic contrast-enhanced (DCE) MRI or DWI. Thirty-eight women with clinically suspected uterine cervical cancer recurrence more than six months after treatment completion were examined with 1.5 Tesla MRI including T2W, DCE, and DWI sequences. Disease was confirmed histologically and correlated with MRI findings. The diagnostic performance of T2W imaging and its combination with either DCE or DWI were analyzed. Sensitivity, positive predictive value, and accuracy were calculated. Thirty-six women had histologically proven recurrence. The accuracy for recurrence detection was 80% with T2W/DCE MRI and 92.1% with T2W/DWI. The addition of DCE sequences did not significantly improve the diagnostic ability of T2W imaging, and this sequence combination misclassified two patients as falsely positive and seven as falsely negative. The T2W/DWI combination revealed a positive predictive value of 100% and only three false negatives. The addition of DWI to T2W sequences considerably improved the diagnostic ability of MRI. Our results support the inclusion of DWI in the initial MRI protocol for the detection of cervical cancer recurrence, leaving DCE sequences as an option for uncertain cases.

  19. Is there a role for diffusion-weighted MRI (DWI) in the diagnosis of central cartilage tumors?

    International Nuclear Information System (INIS)

    Douis, H.; Jeys, L.; Grimer, R.; Vaiyapuri, S.; Davies, A.M.

    2015-01-01

    To assess if diffusion-weighted MRI (DWI) can differentiate between central enchondromas and chondrosarcomas (CS) and if DWI can distinguish low-grade chondroid lesions from high-grade CS. Fifty-two patients with central cartilage tumors were included. Patients underwent conventional MRI and DWI with ADC mapping. The slice on MRI with the most aggressive imaging feature was identified. The corresponding mean and minimum ADC maps of the tumor at this position were measured. There were 24 enchondromas, five atypical cartilaginous lesions, 15 grade 1, three grade 2, two grade 3, and three dedifferentiated CS. Mean ADC values (x 10 -6 mm 2 /s) for enchondromas, atypical cartilaginous tumors, grade 1 CS, grade 2, CS, grade 3 CS and dedifferentiated CS were 1,896, 2,048, 2,152, 2,170, 2,076, and 1,261, respectively. Minimum ADC values (x 10 -6 mm 2 /s) for enchondromas, atypical cartilaginous tumors, grade 1 CS, grade 2, CS, grade 3 CS and dedifferentiated CS were 1,820, 1,752, 2,010, 1,829, 1,752, and 767, respectively. ANOVA test demonstrated a statistically significant difference in mean and minimum ADC values in all groups. Post hoc analysis revealed this was due to difference in mean and minimum ADC values in dedifferentiated CS. The mean ADC value in low-grade chondroid lesions was 2,001, while the ADC value for high-grade CS were 2,132. The minimum ADC value for low-grade chondroid lesions was 1,896, while the minimum ADC for high-grade CS was 1,837. The difference in minimum and mean ADC values was not statistically significant. DWI cannot differentiate between enchondromas and CS and DWI does not aid in the distinction of low-grade chondroid tumors from high-grade CS. (orig.)

  20. Assessment of early renal allograft dysfunction with blood oxygenation level-dependent MRI and diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Yoon [Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Chan Kyo, E-mail: chankyokim@skku.edu [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Park, Byung Kwan [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Sung Ju; Lee, Sanghoon [Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Huh, Wooseong [Department of Nephrology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2014-12-15

    Highlights: • R2* and ADC in renal allografts are moderately correlated with eGFR. • R2* and ADC are lower in early allograft dysfunction than normal allograft function. • No significant difference between AR and ATN was found in both R2* and ADC. - Abstract: Purpose: To investigate blood oxygenation level-dependent (BOLD) MRI and diffusion-weighted imaging (DWI) at 3 T for assessment of early renal allograft dysfunction. Materials and methods: 34 patients with a renal allograft (early dysfunction, 24; normal, 10) were prospectively enrolled. BOLD MRI and DWI were performed at 3 T. R2* and apparent diffusion coefficient (ADC) values were measured in cortex and medulla of the allografts. Correlation between R2* or ADC values and estimated glomerular filtration rate (eGFR) was investigated. R2* or ADC values were compared among acute rejection (AR), acute tubular necrosis (ATN) and normal function. Results: In all renal allografts, cortical or medullary R2* and ADC values were moderately correlated with eGFR (P < 0.05). Early dysfunction group showed lower R2* and ADC values than normal function group (P < 0.05). AR or ATN had lower R2* values than normal allografts (P < 0.05), and ARs had lower cortical ADC values than normal allografts (P < 0.05). No significant difference of R2* or ADC values was found between AR and ATN (P > 0.05). Conclusion: BOLD MRI and DWI at 3 T may demonstrate early functional state of renal allografts, but may be limited in characterizing a cause of early renal allograft dysfunction. Further studies are needed.

  1. 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 ...

  2. Diffusion-Weighted MRI Assessment of Adjacent Disc Degeneration After Thoracolumbar Vertebral Fractures

    Energy Technology Data Exchange (ETDEWEB)

    Noriega, David C., E-mail: dcnoriega1970@gmail.com [Valladolid University Hospital, Spine Department (Spain); Marcia, Stefano, E-mail: stemarcia@gmail.com [SS. Trinità Hospital ASL 8 Cagliari, Department of Radiology (Italy); Ardura, Francisco, E-mail: fardura@ono.com [Valladolid University Hospital, Spine Department (Spain); Lite, Israel Sanchez, E-mail: israelslite@hotmail.com [Valladolid University Hospital, Radiology Department (Spain); Marras, Mariangela, E-mail: mariangela.marrasmd@gmail.com [Azienda Ospedaliero Brotzu (A.O.B.), Department of Radiology (Italy); Saba, Luca, E-mail: lucasaba@tiscali.it [Azienda Ospedaliero Universitaria (A.O.U.), Department of Radiology (Italy)

    2016-09-15

    ObjectiveThe purpose of this study was to assess, by the mean apparent diffusion coefficient (ADC), if a relationship exists between disc ADC and MR findings of adjacent disc degeneration after thoracolumbar fractures treated by anatomic reduction using vertebral augmentation (VAP).Materials and MethodsTwenty non-consecutive patients (mean age 50.7 years; range 45–56) treated because of vertebral fractures, were included in this study. There were 10 A3.1 and 10 A1.2 fractures (AO classification). Surgical treatment using VAP was applied in 14 cases, and conservative in 6 patients. MRI T2-weighted images and mapping of apparent diffusion coefficient (ADC) of the intervertebral disc adjacent to the fractured segment were performed after a mean follow-up of 32 months. A total of 60 discs, 3 per patient, were analysed: infra-adjacent, supra-adjacent and a control disc one level above the supra-adjacent.ResultsNo differences between patients surgically treated and those following a conservative protocol regarding the average ADC values obtained in the 20 control discs analysed were found. Considering all discs, average ADC in the supra-adjacent level was lower than in the infra-adjacent (1.35 ± 0.12 vs. 1.53 ± 0.06; p < 0.001). Average ADC values of the discs used as a control were similar to those of the infra-adjacent level (1.54 ± 0.06). Compared to surgically treated patients, discs at the supra-adjacent fracture level showed statistically significant lower values in cases treated conservatively (p < 0.001). The variation in the delay of surgery had no influence on the average values of ADC at any of the measured levels.ConclusionsADC measurements of the supra-adjacent discs after a mean follow-up of 32 months following thoracolumbar fractures, showed that restoration of the vertebral collapse by minimally invasive VAP prevents posttraumatic disc degeneration.

  3. Effectiveness of 3 T PROPELLER DUO diffusion-weighted MRI in differentiating sinonasal lymphomas and carcinomas

    International Nuclear Information System (INIS)

    Wang, X.; Zhang, Z.; Chen, Q.; Li, J.; Xian, J.

    2014-01-01

    Aim: To evaluate the value of 3 T Periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) DUO diffusion-weighted MRI (DW-MRI) in differentiating sinonasal lymphomas from carcinomas. Materials and methods: PROPELLER DUO DW-MRI was performed in 23 patients with sinonasal lymphomas and 28 patients with carcinomas histologically confirmed at 3 T MRI. Apparent diffusion coefficients (ADCs) were obtained with two different b-values (b = 0 and 700 s/mm 2 , b = 0 and 1000 s/mm 2 ) and two different regions of interest (ROIs) sampling strategies [whole section (WS), partial section (PS)], respectively. Difference in ADCs between sinonasal lymphomas and carcinomas was evaluated using the independent samples t-test or Mann–Whitney U-test. The utility of ADC thresholds for discriminating between them was evaluated by receiver operating characteristic analysis. Results: ADCs of sinonasal lymphomas (WS ADC b0,700 , 0.838 × 10 −3  mm 2 /s) were significantly (p < 0.001) lower than those of carcinomas (WS ADC b0,700 , 1.396 × 10 −3  mm 2 /s). Using a WS ADC b0,700 value of 1.040 × 10 −3  mm 2 /s as the threshold value effectively differentiated sinonasal lymphomas from carcinomas with 100% sensitivity, 82.1% specificity, and 82.1% positive and 100% negative predictive values and 90.2% accuracy (b = 0, 700 s/mm 2 ). There was no significant difference in diagnostic ability between different b-values settings (p > 0.05) and different sampling strategies of ROIs (p > 0.05), respectively. Additionally, there was significant differences in the ADCs between diffuse large B-cell lymphomas and natural killer (NK)/T-cell lymphomas (p < 0.05). Conclusion: PROPELLER DUO DW-MRI can effectively differentiate sinonasal lymphomas from carcinomas. - Highlights: • ADCs of sinonasal lymphomas were lower than those of carcinomas. • ADCs might effectively differentiate sinonasal lymphomas from carcinomas. • Diffuse large B

  4. MRI in seven cases of tacrolimus (FK-506) encephalopathy: utility of FLAIR and diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, M. [Dept. of Radiology, Yamaguchi University School of Medicine, Ube (Japan); Dept. of Radiology, Hokkaido University School of Medicine, Sapporo (Japan); Terae, S.; Chu, B.C.; Kaneko, K.; Kamada, H.; Miyasaka, K. [Dept. of Radiology, Hokkaido University School of Medicine, Sapporo (Japan)

    2001-08-01

    We assessed the utility of fluid-attenuated inversion-recovery (FLAIR) and diffusion-weighted (DWI) images in investigation of tacrolimus (FK-506) encephalopathy, and to see whether we could predict its cause from clinical and imaging data. In seven patients with presumed FK-506 toxicity the areas involved on MRI were similar to those in cyclosporin A (CsA) toxicity. The abnormal signal was most evident on FLAIR in all cases. In three of four patients who underwent DWI, no diffusion abnormalities were detected; in the remaining patient, increased diffusion was seen in the deep white matter bilaterally on the apparent diffusion coefficient map, consistent with the findings on T2-weighted spin-echo and FLAIR images. Five of the six patients for whom we had clinical data showed sudden changes in electrolyte or fluid equilibrium due to diarrhoea, a polyuria or oliguria one day before or on the day of onset of the central nervous system disturbances. We speculate that FK-506 encephalopathy is triggered by the disturbance of the electrolyte and/or fluid equilibrium, given a certain serum level of FK-506. (orig.)

  5. MRI in seven cases of tacrolimus (FK-506) encephalopathy: utility of FLAIR and diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Furukawa, M.; Terae, S.; Chu, B.C.; Kaneko, K.; Kamada, H.; Miyasaka, K.

    2001-01-01

    We assessed the utility of fluid-attenuated inversion-recovery (FLAIR) and diffusion-weighted (DWI) images in investigation of tacrolimus (FK-506) encephalopathy, and to see whether we could predict its cause from clinical and imaging data. In seven patients with presumed FK-506 toxicity the areas involved on MRI were similar to those in cyclosporin A (CsA) toxicity. The abnormal signal was most evident on FLAIR in all cases. In three of four patients who underwent DWI, no diffusion abnormalities were detected; in the remaining patient, increased diffusion was seen in the deep white matter bilaterally on the apparent diffusion coefficient map, consistent with the findings on T2-weighted spin-echo and FLAIR images. Five of the six patients for whom we had clinical data showed sudden changes in electrolyte or fluid equilibrium due to diarrhoea, a polyuria or oliguria one day before or on the day of onset of the central nervous system disturbances. We speculate that FK-506 encephalopathy is triggered by the disturbance of the electrolyte and/or fluid equilibrium, given a certain serum level of FK-506. (orig.)

  6. Implementing diffusion-weighted MRI for body imaging in prospective multicentre trials. Current considerations and future perspectives

    Energy Technology Data Exchange (ETDEWEB)

    DeSouza, N.M.; Winfield, J.M.; Weller, A.; Papoutsaki, M.V.; Doran, S.J.; Collins, D.J. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, CRUK Cancer Imaging Centre, Surrey (United Kingdom); Waterton, J.C.; Jackson, A. [University of Manchester, Manchester Academic Health Sciences Institute, Manchester (United Kingdom); Fournier, L. [Universite Paris Descartes Sorbonne Paris Cite, Assistance Publique-Hopitaux de Paris, Hopital Europeen Georges Pompidou, Radiology Department, Paris (France); Sullivan, D. [Duke Comprehensive Cancer Institute, Durham, NC (United States); Chenevert, T. [University of Michigan Health System, Department of Radiology, Ann Arbor, MI (United States); Boss, M. [National Institute of Standards and Technology (NIST), Applied Physics Division, Boulder, CO (United States); Trattnig, S. [Medical University of Vienna, Department of Biomedical Imaging and Image Guided Therapy, Vienna (Austria); Liu, Y. [European Organisation for Research and Treatment of Cancer, Brussels (Belgium)

    2018-03-15

    For body imaging, diffusion-weighted MRI may be used for tumour detection, staging, prognostic information, assessing response and follow-up. Disease detection and staging involve qualitative, subjective assessment of images, whereas for prognosis, progression or response, quantitative evaluation of the apparent diffusion coefficient (ADC) is required. Validation and qualification of ADC in multicentre trials involves examination of i) technical performance to determine biomarker bias and reproducibility and ii) biological performance to interrogate a specific aspect of biology or to forecast outcome. Unfortunately, the variety of acquisition and analysis methodologies employed at different centres make ADC values non-comparable between them. This invalidates implementation in multicentre trials and limits utility of ADC as a biomarker. This article reviews the factors contributing to ADC variability in terms of data acquisition and analysis. Hardware and software considerations are discussed when implementing standardised protocols across multi-vendor platforms together with methods for quality assurance and quality control. Processes of data collection, archiving, curation, analysis, central reading and handling incidental findings are considered in the conduct of multicentre trials. Data protection and good clinical practice are essential prerequisites. Developing international consensus of procedures is critical to successful validation if ADC is to become a useful biomarker in oncology. (orig.)

  7. Use of diffusion-weighted MRI to modify radiosurgery planning in brain metastases may reduce local recurrence.

    Science.gov (United States)

    Zakaria, Rasheed; Pomschar, Andreas; Jenkinson, Michael D; Tonn, Jörg-Christian; Belka, Claus; Ertl-Wagner, Birgit; Niyazi, Maximilian

    2017-02-01

    Stereotactic radiosurgery (SRS) is an effective and well tolerated treatment for selected brain metastases; however, local recurrence still occurs. We investigated the use of diffusion weighted MRI (DWI) as an adjunct for SRS treatment planning in brain metastases. Seventeen consecutive patients undergoing complete surgical resection of a solitary brain metastasis underwent image analysis retrospectively. SRS treatment plans were generated based on standard 3D post-contrast T1-weighted sequences at 1.5T and then separately using apparent diffusion coefficient (ADC) maps in a blinded fashion. Control scans immediately post operation confirmed complete tumour resection. Treatment plans were compared to one another and with volume of local recurrence at progression quantitatively and qualitatively by calculating the conformity index (CI), the overlapping volume as a proportion of the total combined volume, where 1 = identical plans and 0 = no conformation whatsoever. Gross tumour volumes (GTVs) using ADC and post-contrast T1-weighted sequences were quantitatively the same (related samples Wilcoxon signed rank test = -0.45, p = 0.653) but showed differing conformations (CI 0.53, p recurrence than the standard plan (median 3.53 cm 3 vs. 3.84 cm 3 , p = 0.002). ADC maps may be a useful tool in addition to the standard post-contrast T1-weighted sequence used for SRS planning.

  8. The stratification of severity of acute radiation proctopathy after radiotherapy for cervical carcinoma using diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang Sheng, E-mail: lxsheng500@163.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Fang, Hong, E-mail: hongfang196808@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Song, Yunlong, E-mail: yunlongsong010@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Li, Dechang, E-mail: dechangli1972@sina.com [Department of Pathology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Wang, Yingjie, E-mail: wangyj19710813@sina.com [Department of Radiotherapy, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Zhu, Hongxian, E-mail: hongxian0102@sina.cn [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Meng, Limin, E-mail: liminmeng1977@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Wang, Ping, E-mail: pingwang1978@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Wang, Dong, E-mail: dongwang1964@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China); Fan, Hongxia, E-mail: fanhongxia1975@sina.com [Department of Radiology, Air Force General Hospital of People' s Liberation Army, Beijing 100142 (China)

    2017-02-15

    Objective: To determine whether diffusion-weighted imaging (DWI) can be used for quantitatively evaluating severity of acute radiation proctopathy after radiotherapy for cervical carcinoma. Materials and methods: One hundred and twenty-four patients with cervical carcinoma underwent MR examination including DWI before and after radiotherapy. Acute radiation proctopathy was classified into three groups (grade 0, grade I–II and grade III–IV) according to Toxicity Criteria of the Radiation Therapy Oncology Group (RTOG). The pretreatment ADC (ADC{sub pre}), ADC after treatment (ADC{sub post}) and ADC change (ΔADC) were compared among three groups. In addition, acute radiation proctopathy was classified into good-prognosis group and poor-prognosis group. ADC{sub pre}, ADC{sub post} and ΔADC were compared between two groups. For DWI parameter that had significant difference, discriminatory capability of the parameter was determined using receiver operating characteristics (ROC) analysis. Results: ADC{sub post} and ΔADC were higher in grade I–II group than in grade 0 group (p < 0.05), yielding a sensitivity of 79.3% and specificity of 69.4% for ADC{sub post}, and 85.1%, 72.3% for ΔADC for discrimination between two groups. ADC{sub post} and ΔADC were higher in grade III–IV group than in grade I–II group (p < 0.05), yielding a sensitivity of 80.3% and specificity of 72.5% for ADC{sub post}, and 84.1%, 74.5% for ΔADC for discrimination between two groups. ADC{sub post} and ΔADC were higher in poor-prognosis group than in good-prognosis group (p < 0.05), yielding a sensitivity of 79.5% and specificity of 73.4% for ADC{sub post}, and 87.2%, 78.3% for ΔADC for discrimination between two groups. Conclusion: Diffusion-weighted MRI can be used for quantitative stratification of severity of acute radiation proctopathy, which serves as an important basis for appropriate timely adjustment of radiotherapy for cervical carcinoma in order to maximally reduce the

  9. Modern MRI tools for the characterization of acute demyelinating lesions: value of chemical shift and diffusion-weighted imaging

    International Nuclear Information System (INIS)

    Kueker, W.; Mehnert, F.; Mader, I.; Naegele, T.; Ruff, J.; Gaertner, S.

    2004-01-01

    Acute demyelinating lesions occur in various inflammatory disorders of the CNS. Apart from multiple sclerosis, most cases can be attributed to an overshooting immunological response to infectious agents called acute disseminated encephalomyelitis (ADEM). ADEM, which is mostly characterized by a monophasic course, has a multiphasic variant (MDEM). The early application of corticosteroids has been shown to be beneficial for the outcome; thus, an early diagnosis is highly desirable. Furthermore, the differential diagnosis ruling out neoplastic disorders may be difficult using conventional MRI alone. The potential diagnostic value of advanced MR techniques such as chemical shift imaging (CSI) and diffusion-weighted imaging (DWI) was investigated in a patient with MDEM, who had a new lesion in continuity with the initial disease manifestation. CSI was performed at 1.5 T with a long echo time of 135 ms for the evaluation of N-acetyl-aspartate (NAA) and choline (Cho) and with short TE of 30 ms for macromolecules (mm) and myo-Inositol (mI). DWI was performed using a single-shot isotropic EPI sequence. Whereas acute and chronic areas of demyelination were neither distinguishable on T2- nor on contrast-enhanced T1-weigted images, CSI and DWI revealed different metabolite concentrations and diffusion characteristics within the composite lesion, clearly separating acute from chronic areas of demyelination. In conclusion, the addition of CSI and DWI may add to the diagnostic power of MRI in the setting of demyelinating disorders by identifying areas of acute and chronic demyelination, even in the absence of contrast enhancement. (orig.)

  10. Diffusion-weighted imaging and dynamic contrast-enhanced MRI of experimental breast cancer bone metastases – A correlation study with histology

    Energy Technology Data Exchange (ETDEWEB)

    Merz, Maximilian [Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Hematology, Oncology and Rheumatology, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Seyler, Lisa; Bretschi, Maren; Semmler, Wolfhard [Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Bäuerle, Tobias, E-mail: tobias.baeuerle@uk-erlangen.de [Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Institute of Radiology, University Medical Center Erlangen, Palmsanlage 5, 90154 Erlangen (Germany)

    2015-04-15

    Purpose: To validate imaging parameters from diffusion-weighted imaging and dynamic contrast-enhanced MRI with immunohistology and to non-invasively assess microstructure of experimental breast cancer bone metastases. Materials and methods: Animals bearing breast cancer bone metastases were imaged in a clinical 1.5 T MRI scanner. HASTE sequences were performed to calculate apparent diffusion coefficients. Saturation recovery turbo FLASH sequences were conducted while infusing 0.1 mmol/l Gd–DTPA for dynamic contrast-enhanced MRI to quantify parameters amplitude A and exchange rate constant k{sub ep}. After imaging, bone metastases were analyzed immunohistologically. Results: We found correlations of the apparent diffusion coefficients from diffusion-weighted imaging with tumor cellularity as assessed with cell nuclei staining. Histological vessel maturity was correlated negatively with parameters A and k{sub ep} from dynamic contrast-enhanced MRI. Tumor size correlated inversely with cell density and vessel permeability as well as positively with mean vessel calibers. Parameters from the rim of bone metastases differed significantly from values of the center. Conclusion: In vivo diffusion-weighted imaging and dynamic contrast-enhanced MRI in experimental bone metastases provide information about tumor cellularity and vascularity and correlate well with immunohistology.

  11. Optimal high b-value for diffusion weighted MRI in diagnosing high risk prostate cancers in the peripheral zone.

    Science.gov (United States)

    Agarwal, Harsh K; Mertan, Francesca V; Sankineni, Sandeep; Bernardo, Marcelino; Senegas, Julien; Keupp, Jochen; Daar, Dagane; Merino, Maria; Wood, Bradford J; Pinto, Peter A; Choyke, Peter L; Turkbey, Baris

    2017-01-01

    To retrospectively determine the optimal b-value(s) of diffusion-weighted imaging (DWI) associated with intermediate-high risk cancer in the peripheral zone (PZ) of the prostate. Forty-two consecutive patients underwent multi b-value (16 evenly spaced b-values between 0 and 2000 s/mm 2 ) DWI along with multi-parametric MRI (MP-MRI) of the prostate at 3 Tesla followed by trans-rectal ultrasound/MRI fusion guided targeted biopsy of suspicious lesions detected at MP-MRI. Computed DWI images up to a simulated b-value of 4000 s/mm 2 were also obtained using a pair of b-values (b = 133 and 400 or 667 or 933 s/mm 2 ) from the multi b-value DWI. The contrast ratio of average intensity of the targeted lesions and the background PZ was determined. Receiver operator characteristic curves and the area under the curve (AUCs) were obtained for separating patients eligible for active surveillance with low risk prostate cancers from intermediate-high risk prostate cancers as per the cancer of the prostate risk assessment (CAPRA) scoring system. The AUC first increased then decreased with the increase in b-values reaching maximum at b = 1600 s/mm 2 (0.74) with no statistically significant different AUC of DWI with b-values 1067-2000 s/mm 2 . The AUC of computed DWI increased then decreased with the increase in b-values reaching a maximum of 0.75 around b = 2000 s/mm 2 . There was no statistically significant difference between the AUC of optimal acquired DWI and either of optimal computed DWI. The optimal b-value for acquired DWI in differentiating intermediate-high from low risk prostate cancers in the PZ is b = 1600 s/mm 2 . The computed DWI has similar performance as that of acquired DWI with the optimal performance around b = 2000 s/mm 2 . 4 J. Magn. Reson. Imaging 2017;45:125-131. © 2016 International Society for Magnetic Resonance in Medicine.

  12. Diffusion-weighted MRI in prostatic lesions: Diagnostic performance of normalized ADC using normal peripheral prostatic zone as a reference

    Directory of Open Access Journals (Sweden)

    Tamer F. Taha Ali

    2018-03-01

    ADC in discrimination between cancerous and non-cancerous lesions of the prostate. Keywords: Prostate, Diffusion weighted image (DWI, MRI, Cancer, ADC

  13. Assessment of treatment response by total tumor volume and global apparent diffusion coefficient using diffusion-weighted MRI in patients with metastatic bone disease: a feasibility study.

    Directory of Open Access Journals (Sweden)

    Matthew D Blackledge

    Full Text Available We describe our semi-automatic segmentation of whole-body diffusion-weighted MRI (WBDWI using a Markov random field (MRF model to derive tumor total diffusion volume (tDV and associated global apparent diffusion coefficient (gADC; and demonstrate the feasibility of using these indices for assessing tumor burden and response to treatment in patients with bone metastases. WBDWI was performed on eleven patients diagnosed with bone metastases from breast and prostate cancers before and after anti-cancer therapies. Semi-automatic segmentation incorporating a MRF model was performed in all patients below the C4 vertebra by an experienced radiologist with over eight years of clinical experience in body DWI. Changes in tDV and gADC distributions were compared with overall response determined by all imaging, tumor markers and clinical findings at serial follow up. The segmentation technique was possible in all patients although erroneous volumes of interest were generated in one patient because of poor fat suppression in the pelvis, requiring manual correction. Responding patients showed a larger increase in gADC (median change = +0.18, range = -0.07 to +0.78 × 10(-3 mm2/s after treatment compared to non-responding patients (median change = -0.02, range = -0.10 to +0.05 × 10(-3 mm2/s, p = 0.05, Mann-Whitney test, whereas non-responding patients showed a significantly larger increase in tDV (median change = +26%, range = +3 to +284% compared to responding patients (median change = -50%, range = -85 to +27%, p = 0.02, Mann-Whitney test. Semi-automatic segmentation of WBDWI is feasible for metastatic bone disease in this pilot cohort of 11 patients, and could be used to quantify tumor total diffusion volume and median global ADC for assessing response to treatment.

  14. Diagnostic value of diffusion-weighted MRI for tumor characterization, differentiation and monitoring in pediatric patients with neuroblastic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, Henning [Univ. Hospital Ulm (Germany). Dept. of Diagnostic and Interventional Radiology; Univ. Hospital Wuerzburg (Germany). Dept. of Diagnostic and Interventional Radiology; Li, Mengxia [Univ. Hospital Wuerzburg (Germany). Dept. of Radiation Oncology; Mueller, Verena Rabea [Univ. Hospital Wuerzburg (Germany). Dept. of Paediatrics; Pabst, Thomas [Univ. Hospital Wuerzburg (Germany). Dept. of Diagnostic and Interventional Radiology; Beer, Meinrad [Univ. Hospital Ulm (Germany). Dept. of Diagnostic and Interventional Radiology

    2017-07-15

    We explored the diagnostic value of diffusion-weighted MRI (DWI) for tumor characterization, differentiation and therapy monitoring in pediatric patients with extracranial neuroblastic tumors. All 29 patients (14 girls, median age: 3 years) with neuroblastoma (NB, n = 19), ganglioneuroblastoma (GNB, n = 4) and ganglioneuroma (GN, n = 6) who had had at least one in-house DWI examination since 2005 were identified and retrospectively analyzed. Two independent blinded readers measured ADC values (unit: 10-3 mm{sup 2}/s) and signal intensity ratios (SIRs) of the primary tumor and, if applicable, of the tumor after chemotherapy, metastases and tumor relapse. The pre-treatment ADC was 0.90 ± 0.23 in NB/GNB and 1.70 ± 0.36 in GN without overlap between the two entities for both readers, 0.67 ± 0.14 in metastases and 0.72 ± 0.18 in tumor relapse. With chemotherapy, mean ADC increased to 1.54 ± 0.33 in NB/GNB and to 1.23 ± 0.27 in metastases (p < 0.05). The median SIRs of various tumor lesions vs. liver, vs. muscle tissue and vs. adjacent tissue were significantly higher on DWI (range: 2.4 -9.9) than on ce-T1w (range: 1.0 - 1.8, all p < 0.05). The coefficient of variation (CV) was ≤ 8.0% for ADC and ≤ 16.4% for signal intensity data. Based on mean ADC, DWI distinguishes between NB/GNB and GN with high certainty and provides plausible quantitative data on tumor response to therapy. Lesion conspicuity, as measured by SIR, is superior on DWI, compared to ce-T1w. DWI as a noninvasive, radiation-free and widely available imaging technique should be an integral part of MR imaging for neuroblastic tumors and should undergo prospective evaluation in multicenter studies.

  15. Prospective comparison of T2w-MRI and dynamic-contrast-enhanced MRI, 3D-MR spectroscopic imaging or diffusion-weighted MRI in repeat TRUS-guided biopsies

    Energy Technology Data Exchange (ETDEWEB)

    Portalez, Daniel [Clinique Pasteur, 45, Department of Radiology, Toulouse (France); Rollin, Gautier; Mouly, Patrick; Jonca, Frederic; Malavaud, Bernard [Hopital de Rangueil, Department of Urology, Toulouse Cedex 9 (France); Leandri, Pierre [Clinique Saint Jean, 20, Department of Urology, Toulouse (France); Elman, Benjamin [Clinique Pasteur, 45, Department of Urology, Toulouse (France)

    2010-12-15

    To compare T2-weighted MRI and functional MRI techniques in guiding repeat prostate biopsies. Sixty-eight patients with a history of negative biopsies, negative digital rectal examination and elevated PSA were imaged before repeat biopsies. Dichotomous criteria were used with visual validation of T2-weighted MRI, dynamic contrast-enhanced MRI and literature-derived cut-offs for 3D-spectroscopy MRI (choline-creatine-to-citrate ratio >0.86) and diffusion-weighted imaging (ADC x 10{sup 3} mm{sup 2}/s < 1.24). For each segment and MRI technique, results were rendered as being suspicious/non-suspicious for malignancy. Sextant biopsies, transition zone biopsies and at least two additional biopsies of suspicious areas were taken. In the peripheral zones, 105/408 segments and in the transition zones 19/136 segments were suspicious according to at least one MRI technique. A total of 28/68 (41.2%) patients were found to have cancer. Diffusion-weighted imaging exhibited the highest positive predictive value (0.52) compared with T2-weighted MRI (0.29), dynamic contrast-enhanced MRI (0.33) and 3D-spectroscopy MRI (0.25). Logistic regression showed the probability of cancer in a segment increasing 12-fold when T2-weighted and diffusion-weighted imaging MRI were both suspicious (63.4%) compared with both being non-suspicious (5.2%). The proposed system of analysis and reporting could prove clinically relevant in the decision whether to repeat targeted biopsies. (orig.)

  16. Automated and Semiautomated Segmentation of Rectal Tumor Volumes on Diffusion-Weighted MRI: Can It Replace Manual Volumetry?

    International Nuclear Information System (INIS)

    Heeswijk, Miriam M. van; Lambregts, Doenja M.J.; Griethuysen, Joost J.M. van; Oei, Stanley; Rao, Sheng-Xiang; Graaff, Carla A.M. de; Vliegen, Roy F.A.; Beets, Geerard L.; Papanikolaou, Nikos; Beets-Tan, Regina G.H.

    2016-01-01

    Purpose: Diffusion-weighted imaging (DWI) tumor volumetry is promising for rectal cancer response assessment, but an important drawback is that manual per-slice tumor delineation can be highly time consuming. This study investigated whether manual DWI-volumetry can be reproduced using a (semi)automated segmentation approach. Methods and Materials: Seventy-nine patients underwent magnetic resonance imaging (MRI) that included DWI (highest b value [b1000 or b1100]) before and after chemoradiation therapy (CRT). Tumor volumes were assessed on b1000 (or b1100) DWI before and after CRT by means of (1) automated segmentation (by 2 inexperienced readers), (2) semiautomated segmentation (manual adjustment of the volumes obtained by method 1 by 2 radiologists), and (3) manual segmentation (by 2 radiologists); this last assessment served as the reference standard. Intraclass correlation coefficients (ICC) and Dice similarity indices (DSI) were calculated to evaluate agreement between different methods and observers. Measurement times (from a radiologist's perspective) were recorded for each method. Results: Tumor volumes were not significantly different among the 3 methods, either before or after CRT (P=.08 to .92). ICCs compared to manual segmentation were 0.80 to 0.91 and 0.53 to 0.66 before and after CRT, respectively, for the automated segmentation and 0.91 to 0.97 and 0.61 to 0.75, respectively, for the semiautomated method. Interobserver agreement (ICC) pre and post CRT was 0.82 and 0.59 for automated segmentation, 0.91 and 0.73 for semiautomated segmentation, and 0.91 and 0.75 for manual segmentation, respectively. Mean DSI between the automated and semiautomated method were 0.83 and 0.58 pre-CRT and post-CRT, respectively; DSI between the automated and manual segmentation were 0.68 and 0.42 and 0.70 and 0.41 between the semiautomated and manual segmentation, respectively. Median measurement time for the radiologists was 0 seconds (pre- and post-CRT) for the

  17. Automated and Semiautomated Segmentation of Rectal Tumor Volumes on Diffusion-Weighted MRI: Can It Replace Manual Volumetry?

    Energy Technology Data Exchange (ETDEWEB)

    Heeswijk, Miriam M. van [Department of Radiology, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Surgery, Maastricht University Medical Centre, Maastricht (Netherlands); Lambregts, Doenja M.J., E-mail: d.lambregts@nki.nl [Department of Radiology, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Radiology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Griethuysen, Joost J.M. van [GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Radiology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Oei, Stanley [Department of Radiology, Maastricht University Medical Centre, Maastricht (Netherlands); Rao, Sheng-Xiang [Department of Radiology, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai (China); Graaff, Carla A.M. de [Department of Radiology, Maastricht University Medical Centre, Maastricht (Netherlands); Vliegen, Roy F.A. [Atrium Medical Centre Parkstad/Zuyderland Medical Centre, Heerlen (Netherlands); Beets, Geerard L. [GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Surgery, The Netherlands Cancer Institute, Amsterdam (Netherlands); Papanikolaou, Nikos [Laboratory of Computational Medicine, Institute of Computer Science, FORTH, Heraklion, Crete (Greece); Beets-Tan, Regina G.H. [GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Radiology, The Netherlands Cancer Institute, Amsterdam (Netherlands)

    2016-03-15

    Purpose: Diffusion-weighted imaging (DWI) tumor volumetry is promising for rectal cancer response assessment, but an important drawback is that manual per-slice tumor delineation can be highly time consuming. This study investigated whether manual DWI-volumetry can be reproduced using a (semi)automated segmentation approach. Methods and Materials: Seventy-nine patients underwent magnetic resonance imaging (MRI) that included DWI (highest b value [b1000 or b1100]) before and after chemoradiation therapy (CRT). Tumor volumes were assessed on b1000 (or b1100) DWI before and after CRT by means of (1) automated segmentation (by 2 inexperienced readers), (2) semiautomated segmentation (manual adjustment of the volumes obtained by method 1 by 2 radiologists), and (3) manual segmentation (by 2 radiologists); this last assessment served as the reference standard. Intraclass correlation coefficients (ICC) and Dice similarity indices (DSI) were calculated to evaluate agreement between different methods and observers. Measurement times (from a radiologist's perspective) were recorded for each method. Results: Tumor volumes were not significantly different among the 3 methods, either before or after CRT (P=.08 to .92). ICCs compared to manual segmentation were 0.80 to 0.91 and 0.53 to 0.66 before and after CRT, respectively, for the automated segmentation and 0.91 to 0.97 and 0.61 to 0.75, respectively, for the semiautomated method. Interobserver agreement (ICC) pre and post CRT was 0.82 and 0.59 for automated segmentation, 0.91 and 0.73 for semiautomated segmentation, and 0.91 and 0.75 for manual segmentation, respectively. Mean DSI between the automated and semiautomated method were 0.83 and 0.58 pre-CRT and post-CRT, respectively; DSI between the automated and manual segmentation were 0.68 and 0.42 and 0.70 and 0.41 between the semiautomated and manual segmentation, respectively. Median measurement time for the radiologists was 0 seconds (pre- and post-CRT) for the

  18. Automated and Semiautomated Segmentation of Rectal Tumor Volumes on Diffusion-Weighted MRI: Can It Replace Manual Volumetry?

    Science.gov (United States)

    van Heeswijk, Miriam M; Lambregts, Doenja M J; van Griethuysen, Joost J M; Oei, Stanley; Rao, Sheng-Xiang; de Graaff, Carla A M; Vliegen, Roy F A; Beets, Geerard L; Papanikolaou, Nikos; Beets-Tan, Regina G H

    2016-03-15

    Diffusion-weighted imaging (DWI) tumor volumetry is promising for rectal cancer response assessment, but an important drawback is that manual per-slice tumor delineation can be highly time consuming. This study investigated whether manual DWI-volumetry can be reproduced using a (semi)automated segmentation approach. Seventy-nine patients underwent magnetic resonance imaging (MRI) that included DWI (highest b value [b1000 or b1100]) before and after chemoradiation therapy (CRT). Tumor volumes were assessed on b1000 (or b1100) DWI before and after CRT by means of (1) automated segmentation (by 2 inexperienced readers), (2) semiautomated segmentation (manual adjustment of the volumes obtained by method 1 by 2 radiologists), and (3) manual segmentation (by 2 radiologists); this last assessment served as the reference standard. Intraclass correlation coefficients (ICC) and Dice similarity indices (DSI) were calculated to evaluate agreement between different methods and observers. Measurement times (from a radiologist's perspective) were recorded for each method. Tumor volumes were not significantly different among the 3 methods, either before or after CRT (P=.08 to .92). ICCs compared to manual segmentation were 0.80 to 0.91 and 0.53 to 0.66 before and after CRT, respectively, for the automated segmentation and 0.91 to 0.97 and 0.61 to 0.75, respectively, for the semiautomated method. Interobserver agreement (ICC) pre and post CRT was 0.82 and 0.59 for automated segmentation, 0.91 and 0.73 for semiautomated segmentation, and 0.91 and 0.75 for manual segmentation, respectively. Mean DSI between the automated and semiautomated method were 0.83 and 0.58 pre-CRT and post-CRT, respectively; DSI between the automated and manual segmentation were 0.68 and 0.42 and 0.70 and 0.41 between the semiautomated and manual segmentation, respectively. Median measurement time for the radiologists was 0 seconds (pre- and post-CRT) for the automated method, 41 to 69 seconds (pre-CRT) and

  19. Diffusion-weighted MRI of epithelial ovarian cancers: Correlation of apparent diffusion coefficient values with histologic grade and surgical stage

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Ji-Won, E-mail: fromentin@naver.com [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701 (Korea, Republic of); Rha, Sung Eun, E-mail: serha@catholic.ac.kr [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701 (Korea, Republic of); Oh, Soon Nam, E-mail: hiohsn@catholic.ac.kr [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701 (Korea, Republic of); Park, Michael Yong, E-mail: digirave@kmle.com [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701 (Korea, Republic of); Byun, Jae Young, E-mail: jybyun@catholic.ac.kr [Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701 (Korea, Republic of); Lee, Ahwon, E-mail: klee@catholic.ac.kr [Department of Hospital Pathology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701 (Korea, Republic of)

    2015-04-15

    Highlights: •The solid component of all invasive epithelial cancers showed high b{sub 1000} signal intensity. •ADCs can predict the histologic grade of epithelial ovarian cancer. •ADCs correlate negatively to the surgical stage of epithelial ovarian cancer. •ADCs may be useful imaging biomarkers to assess epithelial ovarian cancer. -- Abstract: Objective: The purpose of this article is to correlate the apparent diffusion coefficient (ADC) values of epithelial ovarian cancers with histologic grade and surgical stage. Materials and methods: We enrolled 43 patients with pathologically proven epithelial ovarian cancers for this retrospective study. All patients underwent preoperative pelvic magnetic resonance imaging (MRI) including diffusion-weighted images with b value of 0 and 1000 s/mm{sup 2} at 3.0-T unit. The mean ADC values of the solid portion of the tumor were measured and compared among different histologic grades and surgical stages. Results: The mean ADC values of epithelial ovarian cancers differed significantly between grade 1 (well-differentiated) and grade 2 (moderately-differentiated) (P = 0.013) as well as between grade 1 and grade 3 (poorly-differentiated) (P = 0.01); however, no statistically significant difference existed between grade 2 and grade 3 (P = 0.737). The receiver-operating characteristic analysis indicated that a cutoff ADC value of less than or equal to 1.09 × 10{sup −3} mm{sup 2}/s was associated with 94.4% sensitivity and 85.7% specificity in distinguishing grade 1 and grade 2/3 cancer. The difference in mean ADC values was statistically significant for early stage (FIGO stage I) and advanced stage (FIGO stage II-IV) cancer (P = 0.011). The interobserver agreement for the mean ADC values of epithelial ovarian cancers was excellent. Conclusion: The mean ADC values of the solid portion of epithelial ovarian cancers negatively correlated to histologic grade and surgical stage. The mean ADC values may be useful imaging

  20. Detection of hyperacute parenchymal hemorrhage of the brain using echo-planar T2{sup *}-weighted and diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Wiesmann, M. [Dept. of Radiology, Medizinische Universitaet zu Luebeck (Germany); Mayer, T.E.; Yousry, I.; Brueckmann, H. [Dept. of Neuroradiology, Klinikum Grosshadern, Ludwig-Maximilians-Universitaet, Muenchen (Germany); Hamann, G.F. [Dept. of Neurology, Klinikum Grosshadern, Ludwig-Maximilians-Universitaet, Muenchen (Germany)

    2001-05-01

    We investigated the usefulness of echo-planar imaging (EPI) as well as T2{sup *}-weighted and diffusion-weighted MRI (DWI) to identify hyperacute hemorrhage (within 24 h after ictus) in the brain. Seven patients were examined 3.5 to 24 h after onset of symptoms using a whole-body 1.5-T MR system. Two diffusion-weighted sequences were run to obtain isotropic and anisotropic diffusion images. Apparent diffusion coefficients (ADC) were calculated from the isotropic diffusion images. All DWI images as well as the T2*-weighted EPI images showed the hematomas as either discrete, deeply hypointense homogeneous lesions, or as lesions of mixed signal intensity containing hypointense areas. We conclude that even in the early phase after hemorrhage, sufficient amounts of paramagnetic deoxyhemoglobin are present in intracerebral hemorrhages to cause hypointensity on EPI T2{sup *}-weighted and DWI images; thus, use of ultrafast EPI allows identification of intracerebral hemorrhage. (orig.)

  1. A variational image-based approach to the correction of susceptibility artifacts in the alignment of diffusion weighted and structural MRI.

    Science.gov (United States)

    Tao, Ran; Fletcher, P Thomas; Gerber, Samuel; Whitaker, Ross T

    2009-01-01

    This paper presents a method for correcting the geometric and greyscale distortions in diffusion-weighted MRI that result from inhomogeneities in the static magnetic field. These inhomogeneities may due to imperfections in the magnet or to spatial variations in the magnetic susceptibility of the object being imaged--so called susceptibility artifacts. Echo-planar imaging (EPI), used in virtually all diffusion weighted acquisition protocols, assumes a homogeneous static field, which generally does not hold for head MRI. The resulting distortions are significant, sometimes more than ten millimeters. These artifacts impede accurate alignment of diffusion images with structural MRI, and are generally considered an obstacle to the joint analysis of connectivity and structure in head MRI. In principle, susceptibility artifacts can be corrected by acquiring (and applying) a field map. However, as shown in the literature and demonstrated in this paper, field map corrections of susceptibility artifacts are not entirely accurate and reliable, and thus field maps do not produce reliable alignment of EPIs with corresponding structural images. This paper presents a new, image-based method for correcting susceptibility artifacts. The method relies on a variational formulation of the match between an EPI baseline image and a corresponding T2-weighted structural image but also specifically accounts for the physics of susceptibility artifacts. We derive a set of partial differential equations associated with the optimization, describe the numerical methods for solving these equations, and present results that demonstrate the effectiveness of the proposed method compared with field-map correction.

  2. Central pontine myelinolysis with a hyperintense lesion in diffusion weighted MRI: overview by means of a case report

    International Nuclear Information System (INIS)

    Kuhn, J.; Bewermeyer, H.; Harzheim, A.

    2005-01-01

    Central pontine myelinolysis (CPM) is a demyelinating disease of the pons often associated with demyelination of other areas of the central nervous system (CNS). The etiology and pathogenesis of this disorder are still not fully understood. However, almost all cases of CPM are related to severe diseases or chronic alcoholism and occur in the setting of rapidly corrected serum hyponatremia and hypotonicity respectively. Depending on the involvement of other CNS structures, the clinical picture can vary considerably. Magnetic resonance imaging is the most sensitive investigation for the antemortem diagnosis of CPM, although the radiological findings lag behind and do not necessarily correlate with the clinical picture. Quite obviously diffusion-weighted imaging can be useful in the rapid diagnosis of CPM. This short review summarizes the current knowledge on the pathogenesis, clinical presentation, radiological findings, prognosis and therapeutic approaches of CPM. Characteristical clinical features and MR-findings including hyperintensity on diffusion-weighted images are illustrated by a typical case. (orig.)

  3. Alterations in the inferior longitudinal fasciculus in autism and associations with visual processing: a diffusion-weighted MRI study

    OpenAIRE

    Boets, Bart; Van Eylen, Lien; Sitek, Kevin; Moors, Pieter; Noens, Ilse; Steyaert, Jean; Sunaert, Stefan; Wagemans, Johan

    2018-01-01

    Background: One of the most reported neural features of autism spectrum disorder (ASD) is the alteration of multiple long-range white matter fiber tracts, as assessed by diffusion-weighted imaging and indexed by reduced fractional anisotropy (FA). Recent methodological advances, however, have shown that this same pattern of reduced FA may be an artifact resulting from excessive head motion and poorer data quality and that aberrant structural connectivity in children with ASD is confined to th...

  4. Whole-Body MRI Virtual Autopsy Using Diffusion-weighted Imaging With Background Suppression (DWIBS) at 3 T in a Child Succumbing to Chordoma.

    Science.gov (United States)

    Andronikou, Savvas; Kemp, Marnie L; Meiring, Michelle

    2017-03-01

    We report the use of diffusion-weighted imaging with background suppression (DWIBS) in pediatric virtual magnetic resonance imaging (MRI) autopsy of a child who succumbed to chordoma. A 10-year-old girl who succumbed to relapse of a chordoma underwent whole-body virtual MRI autopsy 12 hours postmortem with short Tau inversion recovery (STIR) and DWIBS on 3 T, which demonstrated the primary mass, local and cardiac invasion, and metastatic disease to the thorax, abdomen, head/neck, and musculoskeletal system. Postmortem virtual MRI autopsy including DWIBS successfully demonstrated the transthoracic spread of chordoma and invasion of the heart, resulting in blood-borne metastases. Motion and respiratory artifact were not factors during virtual autopsy using DWIBS on 3 T, making ideal use of this technology.

  5. Comparison of endorectal coil and nonendorectal coil T2W and diffusion-weighted MRI at 3 Tesla for localizing prostate cancer: correlation with whole-mount histopathology.

    Science.gov (United States)

    Turkbey, Baris; Merino, Maria J; Gallardo, Elma Carvajal; Shah, Vijay; Aras, Omer; Bernardo, Marcelino; Mena, Esther; Daar, Dagane; Rastinehad, Ardeshir R; Linehan, W Marston; Wood, Bradford J; Pinto, Peter A; Choyke, Peter L

    2014-06-01

    To compare utility of T2-weighted (T2W) MRI and diffusion-weighted MRI (DWI-MRI) obtained with and without an endorectal coil at 3 Tesla (T) for localizing prostate cancer. This Institutional Review Board-approved study included 20 patients (median prostate-specific antigen, 8.4 ng/mL). Patients underwent consecutive prostate MRIs at 3T, first with a surface coil alone, then with combination of surface, endorectal coils (dual coil) followed by robotic assisted radical prostatectomy. Lesions were mapped at time of acquisition on dual-coil T2W, DWI-MRI. To avoid bias, 6 months later nonendorectal coil T2W, DWI-MRI were mapped. Both MRI evaluations were performed by two readers blinded to pathology with differences resolved by consensus. A lesion-based correlation with whole-mount histopathology was performed. At histopathology 51 cancer foci were present ranging in size from 2 to 60 mm. The sensitivity of the endorectal dual-coil, nonendorectal coil MRIs were 0.76, 0.45, respectively. PPVs for endorectal dual-coil, nonendorectal coil MRI were 0.80, 0.64, respectively. Mean size of detected lesions with nonendorectal coil MRI were larger than those detected by dual-coil MRI (22 mm versus 17.4 mm). Dual-coil prostate MRI detected more cancer foci than nonendorectal coil MRI. While nonendorectal coil MRI is an attractive alternative, physicians performing prostate MRI should be aware of its limitations. Copyright © 2013 Wiley Periodicals, Inc.

  6. Incremental value of diffusion weighted and dynamic contrast enhanced MRI in the detection of locally recurrent prostate cancer after radiation treatment: preliminary results

    International Nuclear Information System (INIS)

    Akin, Oguz; Vargas, Hebert Alberto; Hricak, Hedvig; Gultekin, David H.; Zheng, Junting; Moskowitz, Chaya; Pei, Xin; Sperling, Dahlia; Zelefsky, Michael J.; Schwartz, Lawrence H.

    2011-01-01

    To assess the incremental value of diffusion-weighted (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI) to T2-weighted MRI (T2WI) in detecting locally recurrent prostate cancer after radiotherapy. Twenty-four patients (median age, 70 years) with a history of radiotherapy-treated prostate cancer underwent multi-parametric MRI (MP-MRI) and transrectal prostate biopsy. Two readers independently scored the likelihood of cancer on a 1-5 scale, using T2WI alone and then adding DW-MRI and DCE-MRI. Areas under receiver operating characteristic curves (AUCs) were estimated at the patient and prostate-side levels. The apparent diffusion coefficient (ADC) from DW-MRI and the K trans , k ep , v e , AUGC90 and AUGC180 from DCE-MRI were recorded. Biopsy was positive in 16/24 (67%) and negative in 8/24 (33%) patients. AUCs for readers 1 and 2 increased from 0.64 and 0.53 to 0.95 and 0.86 with MP-MRI, at the patient level, and from 0.73 and 0.66 to 0.90 and 0.79 with MP-MRI, at the prostate-side level (p values -3 mm 2 /s)], median K trans [1.07 vs. 0.34 (1/min)], and k ep [2.06 vs 1.0 (1/min)] (p values < 0.05). MP-MRI was significantly more accurate than T2WI alone in detecting locally recurrent prostate cancer after radiotherapy. (orig.)

  7. Incremental value of diffusion weighted and dynamic contrast enhanced MRI in the detection of locally recurrent prostate cancer after radiation treatment: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Akin, Oguz; Vargas, Hebert Alberto; Hricak, Hedvig [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States); Gultekin, David H. [Memorial Sloan-Kettering Cancer Center, Medical Physics, New York, NY (United States); Zheng, Junting; Moskowitz, Chaya [Memorial Sloan-Kettering Cancer Center, Epidemiology and Biostatistics, New York, NY (United States); Pei, Xin; Sperling, Dahlia; Zelefsky, Michael J. [Memorial Sloan-Kettering Cancer Center, Radiation Oncology, New York, NY (United States); Schwartz, Lawrence H. [Columbia University College of Physicians and Surgeons, Radiology, New York, NY (United States)

    2011-09-15

    To assess the incremental value of diffusion-weighted (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI) to T2-weighted MRI (T2WI) in detecting locally recurrent prostate cancer after radiotherapy. Twenty-four patients (median age, 70 years) with a history of radiotherapy-treated prostate cancer underwent multi-parametric MRI (MP-MRI) and transrectal prostate biopsy. Two readers independently scored the likelihood of cancer on a 1-5 scale, using T2WI alone and then adding DW-MRI and DCE-MRI. Areas under receiver operating characteristic curves (AUCs) were estimated at the patient and prostate-side levels. The apparent diffusion coefficient (ADC) from DW-MRI and the K{sup trans}, k{sub ep}, v{sub e}, AUGC90 and AUGC180 from DCE-MRI were recorded. Biopsy was positive in 16/24 (67%) and negative in 8/24 (33%) patients. AUCs for readers 1 and 2 increased from 0.64 and 0.53 to 0.95 and 0.86 with MP-MRI, at the patient level, and from 0.73 and 0.66 to 0.90 and 0.79 with MP-MRI, at the prostate-side level (p values < 0.05). Biopsy-positive and biopsy-negative prostate sides differed significantly in median ADC [1.44 vs. 1.68 (x 10{sup -3} mm{sup 2}/s)], median K{sup trans} [1.07 vs. 0.34 (1/min)], and k{sub ep} [2.06 vs 1.0 (1/min)] (p values < 0.05). MP-MRI was significantly more accurate than T2WI alone in detecting locally recurrent prostate cancer after radiotherapy. (orig.)

  8. Detection of hepatocellular carcinoma in gadoxetic acid-enhanced MRI and diffusion-weighted MRI with respect to the severity of liver cirrhosis

    International Nuclear Information System (INIS)

    Kim, Ah Yeong; Kim, Young Kon; Lee, Min Woo; Park, Min Jung; Hwang, Jiyoung; Lee, Mi Hee; Lee, Jae Won

    2012-01-01

    Background As gadoxetic acid-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) have been widely used for the evaluation of hepatocellular carcinoma (HCC), it is clinically relevant to determine the diagnostic efficacy of gadoxetic acid-enhanced MRI and DWI for detection of HCCs with respect to the severity of liver cirrhosis. Purpose To compare the diagnostic accuracy and sensitivity of gadoxetic acid-enhanced MRI and DWI for detection of HCCs with respect to the severity of liver cirrhosis. Material and Methods A total of 189 patients with 240 HCCs (≤3.0 cm) (Child-Pugh A, 81 patients with 90 HCCs; Child-Pugh B, 65 patients with 85 HCCs; Child-Pugh C, 43 patients with 65 HCCs) underwent DWI and gadoxetic acid-enhanced MRI at 3.0 T. A gadoxetic acid set (dynamic and hepatobiliary phase plus T2-weighted image) and DWI set (DWI plus unenhanced MRIs) for each Child-Pugh class were analyzed independently by two observers for detecting HCCs using receiver-operating characteristic analysis. The diagnostic accuracy and sensitivity were calculated. Results There was a trend toward decreased diagnostic accuracy for gadoxetic acid and DWI set with respect to the severity of cirrhosis (Child-Pugh A [mean 0.974, 0.961], B [mean 0.904, 0.863], C [mean 0.779, 0.760]). For both observers, the sensitivities of both image sets were highest in Child-Pugh class A (mean 95.6%, 93.9%), followed by class B (mean 83.0%, 77.1%), and class C (mean 60.6%, 60.0%) (P < 0.05). Conclusion In HCC detection, the diagnostic accuracy and sensitivity for gadoxetic acid-enhanced MRI and DWI were highest in Child-Pugh class A, followed by Child-Pugh class B, and Child-Pugh class C, indicating a tendency toward decreased diagnostic capability with the severity of cirrhosis

  9. Correlation of human papillomavirus status with apparent diffusion coefficient of diffusion-weighted MRI in head and neck squamous cell carcinomas.

    Science.gov (United States)

    Driessen, Juliette P; van Bemmel, Alexander J M; van Kempen, Pauline M W; Janssen, Luuk M; Terhaard, Chris H J; Pameijer, Frank A; Willems, Stefan M; Stegeman, Inge; Grolman, Wilko; Philippens, Marielle E P

    2016-04-01

    Identification of prognostic patient characteristics in head and neck squamous cell carcinoma (HNSCC) is of great importance. Human papillomavirus (HPV)-positive HNSCCs have favorable response to (chemo)radiotherapy. Apparent diffusion coefficient, derived from diffusion-weighted MRI, has also shown to predict treatment response. The purpose of this study was to evaluate the correlation between HPV status and apparent diffusion coefficient. Seventy-three patients with histologically proven HNSCC were retrospectively analyzed. Mean pretreatment apparent diffusion coefficient was calculated by delineation of total tumor volume on diffusion-weighted MRI. HPV status was analyzed and correlated to apparent diffusion coefficient. Six HNSCCs were HPV-positive. HPV-positive HNSCC showed significantly lower apparent diffusion coefficient compared to HPV-negative. This correlation was independent of other patient characteristics. In HNSCC, positive HPV status correlates with low mean apparent diffusion coefficient. The favorable prognostic value of low pretreatment apparent diffusion coefficient might be partially attributed to patients with a positive HPV status. © 2015 Wiley Periodicals, Inc. Head Neck 38: E613-E618, 2016. © 2015 Wiley Periodicals, Inc.

  10. Non-echoplanar diffusion-weighted MRI in children and adolescents with cholesteatoma: reliability and pitfalls in comparison to middle ear surgery

    International Nuclear Information System (INIS)

    Kalle, Thekla von; Amrhein, Peter; Koitschev, Assen

    2015-01-01

    Currently, there is only limited and contradictory evidence of the role of diffusion-weighted MRI (DW-MRI) in the management of children with cholesteatoma. To provide surgically controlled data that may allow to replace second-look surgery by non-echoplanar DW-MRI in children. Fifty-five children and adolescents with a median age of 8.6 years (2.2-17.7 years) underwent 61 preoperative half-Fourier acquisition single-shot turbo spin-echo (HASTE) DW-MRI of their petrous bone. Surgical interventions followed within 24 h (79%), within 5 months (20%) or at 18 months (1 case). Surgery detected a cholesteatoma or retraction pocket in 41 of 61 cases (67%). In 49 cases (80%), the MR result was confirmed by surgical findings. Two MR findings were false-positive and 10 false-negative (including cholesteatomas <4 mm). HASTE DW-MRI alone had a sensitivity of 76% and a specificity of 90%. The positive predictive value was 94%, the negative predictive value 64%. In combination with preoperative otoscopy, sensitivity was 90% and negative predictive value 82%. DW-MRI correctly detected the majority of lesions but could not reliably exclude small cholesteatomas and empty retraction pockets. We would therefore not generally recommend MR as a substitute for second-look surgery. (orig.)

  11. Non-echoplanar diffusion-weighted MRI in children and adolescents with cholesteatoma: reliability and pitfalls in comparison to middle ear surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, Thekla von [Olgahospital Klinikum Stuttgart, Pediatric Radiology, Radiologisches Institut, Stuttgart (Germany); Amrhein, Peter; Koitschev, Assen [Olgahospital Klinikum Stuttgart, Division of Pediatric Otorhinolaryngology and Otology, Department of Otorhinolaryngology, Stuttgart (Germany)

    2015-07-15

    Currently, there is only limited and contradictory evidence of the role of diffusion-weighted MRI (DW-MRI) in the management of children with cholesteatoma. To provide surgically controlled data that may allow to replace second-look surgery by non-echoplanar DW-MRI in children. Fifty-five children and adolescents with a median age of 8.6 years (2.2-17.7 years) underwent 61 preoperative half-Fourier acquisition single-shot turbo spin-echo (HASTE) DW-MRI of their petrous bone. Surgical interventions followed within 24 h (79%), within 5 months (20%) or at 18 months (1 case). Surgery detected a cholesteatoma or retraction pocket in 41 of 61 cases (67%). In 49 cases (80%), the MR result was confirmed by surgical findings. Two MR findings were false-positive and 10 false-negative (including cholesteatomas <4 mm). HASTE DW-MRI alone had a sensitivity of 76% and a specificity of 90%. The positive predictive value was 94%, the negative predictive value 64%. In combination with preoperative otoscopy, sensitivity was 90% and negative predictive value 82%. DW-MRI correctly detected the majority of lesions but could not reliably exclude small cholesteatomas and empty retraction pockets. We would therefore not generally recommend MR as a substitute for second-look surgery. (orig.)

  12. Diffusion-weighted imaging as part of hybrid PET/MRI protocols for whole-body cancer staging: Does it benefit lesion detection?

    Energy Technology Data Exchange (ETDEWEB)

    Buchbender, Christian, E-mail: christian.buchbender@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Hartung-Knemeyer, Verena, E-mail: verena.hartung@uk-essen.de [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, Hufelandstr. 55, D-45147 Essen (Germany); Beiderwellen, Karsten, E-mail: karsten.beiderwellen@uk-essen.de [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Hufelandstr. 55, D-45147 Essen (Germany); Heusch, Philipp, E-mail: philipp.heusch@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Kühl, Hilmar, E-mail: hilmar.kuehl@uni-due.de [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Hufelandstr. 55, D-45147 Essen (Germany); Lauenstein, Thomas C., E-mail: thomas.lauenstein@uk-essen.de [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Hufelandstr. 55, D-45147 Essen (Germany); Forsting, Michael, E-mail: michael.forsting@uk-essen.de [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Hufelandstr. 55, D-45147 Essen (Germany); Antoch, Gerald, E-mail: antoch@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Heusner, Till A., E-mail: heusner@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany)

    2013-05-15

    Purpose: Positron emission tomography/magnetic resonance imaging (PET/MRI) requires efficient scan protocols for whole-body cancer staging. The aim of this study was to evaluate if the application of diffusion-weighted MR imaging (DWI) results in a diagnostic benefit for lesion detection in oncologic patients if added to a whole-body [18F]-fluorodesoxyglucose ([18F]-FDG) PET/MRI protocol. Methods: 25 consecutive oncologic patients (16 men, 9 women; age 57 ± 12 years) prospectively underwent whole-body [18F]-FDG-PET/MRI including DWI on a hybrid PET/MRI scanner. A team of two readers assessed [18F]-FDG PET/MRI without DWI for primary tumors and metastases. In a second session, now considering DWI, readers reassessed [18F]-FDG PET/MRI accordingly. Additionally, the lesion-to-background contrast on [18F]-FDG PET and DWI was rated qualitatively (0, invisible; 1, low; 2, intermediate; 3, high). Wilcoxon's signed-rank test was performed to test for differences in the lesion-to-background contrast. Results: 49 lesions were detected in 16 patients (5 primaries, 44 metastases). All 49 lesions were concordantly detected by [18F]-FDG PET/MRI alone and [18F]-FDG PET/MRI with DWI. The lesion-to-background contrast on DWI compared to [18F]-FDG PET was rated lower in 22 (44.9%) of 49 detected lesions resulting in a significantly higher lesion-to-background contrast on [18F]-FDG PET compared to DWI (P = 0.001). Conclusions: DWI as part of whole-body [18F]-FDG PET/MRI does not benefit lesion detection. Given the necessity to optimize imaging protocols with regard to patient comfort and efficacy, DWI has to be questioned as a standard tool for whole-body staging in oncologic PET/MRI.

  13. Comparison of conventional and diffusion-weighted MRI and proton MR spectroscopy in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like events

    Energy Technology Data Exchange (ETDEWEB)

    Abe, K.; Hikita, T.; Sakoda, S. [Department of Neurology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Osaka (Japan); Yoshimura, H.; Tanaka, H.; Fujita, N. [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Osaka (Japan)

    2004-02-01

    The mechanism of neurological disturbances in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is controversial. We studied 12 patients with MELAS using conventional and diffusion weighted MRI (DWI) and MR spectroscopy (MRS), to look at the physiopathology of the stroke-like events. Although conventional MRI showed lesions in all patients, DWI was more sensitive. One patient did not show high signal on DWI 48 h after a from stroke-like episode, but MRS demonstrated a lactate peak in left occipital lobe; 2 weeks after the attack, high signal was demonstrated on the right frontal lobe where MRS had shown a lactate peak. Our findings suggest a possible predictive ability of {sup 1}H-MRS, in showing early MELAS lesions and supports the hypothesis that mitochondrial metabolic dysfunction may precedes abnormalities on DWI. (orig.)

  14. Meningoencephalitis caused by Streptococcus pneumoniae: a diagnostic and therapeutic challenge. Diagnosis with diffusion-weighted MRI leading to treatment with corticosteroids

    International Nuclear Information System (INIS)

    Jorens, Philippe G.; Demey, Hendrik E.; Parizel, Paul M.; Smets, Katrien; Jadoul, Kris; Verbeek, M.M.; Wevers, R.A.; Cras, Patrick

    2005-01-01

    Streptococcus pneumoniae is a common cause of bacterial meningitis but only rarely causes other infections such as brain abscess, encephalitis, encephalomyelitis or meningoencephalitis. We report on three adult patients with meningoencephalitis caused by S. pneumoniae. In all three, CT and MRI revealed widespread brain lesions, suggesting extensive parenchymal injury. Diffusion-weighted MRI showed lesions with restricted diffusion, reflecting local areas of ischaemia with cytotoxic oedema secondary to an immunologically mediated necrotising vasculitis and thrombosis. High levels of markers of neuronal, glial and myelin damage were found in the cerebrospinal fluid. According to the literature, brain parenchyma lesions in adults with pneumococcal meningoencephalitis are often associated with death or severe neurological deficit. Our patients were treated with pulse doses of glucocorticoids: this resulted in dramatic clinical improvement and an excellent final neurological recovery. (orig.)

  15. Comparison of conventional and diffusion-weighted MRI and proton MR spectroscopy in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like events

    International Nuclear Information System (INIS)

    Abe, K.; Hikita, T.; Sakoda, S.; Yoshimura, H.; Tanaka, H.; Fujita, N.

    2004-01-01

    The mechanism of neurological disturbances in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is controversial. We studied 12 patients with MELAS using conventional and diffusion weighted MRI (DWI) and MR spectroscopy (MRS), to look at the physiopathology of the stroke-like events. Although conventional MRI showed lesions in all patients, DWI was more sensitive. One patient did not show high signal on DWI 48 h after a from stroke-like episode, but MRS demonstrated a lactate peak in left occipital lobe; 2 weeks after the attack, high signal was demonstrated on the right frontal lobe where MRS had shown a lactate peak. Our findings suggest a possible predictive ability of 1 H-MRS, in showing early MELAS lesions and supports the hypothesis that mitochondrial metabolic dysfunction may precedes abnormalities on DWI. (orig.)

  16. Meningoencephalitis caused by Streptococcus pneumoniae: a diagnostic and therapeutic challenge. Diagnosis with diffusion-weighted MRI leading to treatment with corticosteroids

    Energy Technology Data Exchange (ETDEWEB)

    Jorens, Philippe G.; Demey, Hendrik E. [University Hospital of Antwerp, UZA, Department of Intensive Care Medicine, Edegem (Belgium); Parizel, Paul M. [University of Antwerp, Department of Radiology, Edegem (Belgium); Smets, Katrien [University of Antwerp, Department of Neurology, Edegem (Belgium); General Hospital AZ Middelares, Department of Neurology, Sint-Niklaas (Belgium); Jadoul, Kris [General Hospital AZ Middelares, Department of Neurology, Sint-Niklaas (Belgium); Verbeek, M.M.; Wevers, R.A. [University Hospital of Nijmegen, Laboratory of Paediatrics and Neurology, Nijmegen (Netherlands); Cras, Patrick [University of Antwerp, Department of Neurology, Edegem (Belgium)

    2005-10-01

    Streptococcus pneumoniae is a common cause of bacterial meningitis but only rarely causes other infections such as brain abscess, encephalitis, encephalomyelitis or meningoencephalitis. We report on three adult patients with meningoencephalitis caused by S. pneumoniae. In all three, CT and MRI revealed widespread brain lesions, suggesting extensive parenchymal injury. Diffusion-weighted MRI showed lesions with restricted diffusion, reflecting local areas of ischaemia with cytotoxic oedema secondary to an immunologically mediated necrotising vasculitis and thrombosis. High levels of markers of neuronal, glial and myelin damage were found in the cerebrospinal fluid. According to the literature, brain parenchyma lesions in adults with pneumococcal meningoencephalitis are often associated with death or severe neurological deficit. Our patients were treated with pulse doses of glucocorticoids: this resulted in dramatic clinical improvement and an excellent final neurological recovery. (orig.)

  17. Diffusion-weighted imaging in relation to morphology on dynamic contrast enhancement MRI: the diagnostic value of characterizing non-puerperal mastitis.

    Science.gov (United States)

    Zhang, Lina; Hu, Jiani; Guys, Nicholas; Meng, Jinli; Chu, Jianguo; Zhang, Weisheng; Liu, Ailian; Wang, Shaowu; Song, Qingwei

    2018-03-01

    To demonstrate the value of diffusion-weighted imaging (DWI) in the characterisation of mastitis lesions. Sixty-one non-puerperal patients with pathologically confirmed single benign mastitis lesions underwent preoperative examinations with conventional MRI and axial DWI. Patients were categorised into three groups: (1) periductal mastitis (PDM), (2) granulomatous lobular mastitis (GLM), and (3) infectious abscess (IAB). Apparent diffusion coefficient (ADC) values of each lesion were recorded. A one-way ANOVA with logistic analysis was performed to compare ADC values and other parameters. Discriminative abilities of DWI modalities were compared using the area under the receiver operating characteristic curve (AUC). P mastitis subtypes. • Mastitis subtypes exhibit different characteristics on DWI and DCE MRI. • ADC values are helpful in isolating PDM from other mastitis lesions. • Distribution of non-mass enhancement also has value in comparing mastitis subtypes.

  18. Role of MRI and added value of diffusion-weighted and gadolinium-enhanced MRI for the diagnosis of local recurrence from rectal cancer.

    Science.gov (United States)

    Molinelli, Valeria; Angeretti, Maria Gloria; Duka, Ejona; Tarallo, Nicola; Bracchi, Elena; Novario, Raffaele; Fugazzola, Carlo

    2018-03-14

    To evaluate whether the addition of gadolinium-enhanced MRI and diffusion-weighted imaging (DWI) improves T2 sequence performance for the diagnosis of local recurrence (LR) from rectal cancer and to assess which approach is better at formulating this diagnosis among readers with different experience. Forty-three patients with suspected LR underwent pelvic MRI with T2 weighted (T2) sequences, gadolinium fat-suppressed T1 weighted sequences (post-contrast T1), and DWI sequences. Three readers (expert: G, intermediate: E, resident: V) scored the likelihood of LR on T2, T2 + post-contrast T1, T2 + DWI, and T2 + post-contrast T1 + DWI. In total, 18/43 patients had LR; on T2 images, the expert reader achieved an area under the ROC curve (AUC) of 0.916, sensitivity of 88.9%, and specificity of 76%; the intermediate reader achieved values of 0.890, 88.9%, and 48%, respectively, and the resident achieved values of 0.852, 88.9%, and 48%, respectively. DWI significantly improved the AUC value for the expert radiologist by up to 0.999 (p = 0.04), while post-contrast T1 significantly improved the AUC for the resident by up to 0.950 (p = 0.04). For the intermediate reader, both the T2 + DWI AUC and T2 + post-contrast T1 AUC were better than the T2 AUC (0.976 and 0.980, respectively), but with no statistically significant difference. No statistically significant difference was achieved by any of the three readers by comparing either the T2 + DWI AUCs to the T2 + post-contrast T1 AUCs or the AUCs of the two pairs of sequences to those of the combined three sequences. Furthermore, using the T2 sequences alone, all of the readers achieved a fair number of "equivocal" cases: they decreased with the addition of either DWI or post-contrast T1 sequences and, for the two less experienced readers, they decreased even more with the three combined sequences. Both DWI and T1 post-contrast MRI increased diagnostic performance for LR diagnosis compared to T2; however, no

  19. Combined diffusion-weighted, blood oxygen level-dependent, and dynamic contrast-enhanced MRI for characterization and differentiation of renal cell carcinoma.

    Science.gov (United States)

    Notohamiprodjo, Mike; Staehler, Michael; Steiner, Nicole; Schwab, Felix; Sourbron, Steven P; Michaely, Henrik J; Helck, Andreas D; Reiser, Maximilian F; Nikolaou, Konstantin

    2013-06-01

    To investigate a multiparametric magnetic resonance imaging (MRI) approach comprising diffusion-weighted imaging (DWI), blood oxygen-dependent (BOLD), and dynamic contrast-enhanced (DCE) MRI for characterization and differentiation of primary renal cell carcinoma (RCC). Fourteen patients with clear-cell carcinoma and four patients with papillary RCC were examined with DWI, BOLD MRI, and DCE MRI at 1.5T. The apparent diffusion coefficient (ADC) was calculated with a monoexponential decay. The spin-dephasing rate R2* was derived from parametric R2* maps. DCE-MRI was analyzed using a two-compartment exchange model allowing separation of perfusion (plasma flow [FP] and plasma volume [VP]), permeability (permeability surface area product [PS]), and extravascular extracellular volume (VE). Statistical analysis was performed with Wilcoxon signed-rank test, Pearson's correlation coefficient, and receiver operating characteristic curve analysis. Clear-cell RCC showed higher ADC and lower R2* compared to papillary subtypes, but differences were not significant. FP of clear-cell subtypes was significantly higher than in papillary RCC. Perfusion parameters showed moderate but significant inverse correlation with R2*. VE showed moderate inverse correlation with ADC. Fp and Vp showed best sensitivity for histological differentiation. Multiparametric MRI comprising DWI, BOLD, and DCE MRI is feasible for assessment of primary RCC. BOLD moderately correlates to DCE MRI-derived perfusion. ADC shows moderate correlation to the extracellular volume, but does not correlate to tumor oxygenation or perfusion. In this preliminary study DCE-MRI appeared superior to BOLD and DWI for histological differentiation. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

  20. 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

  1. 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.

  2. 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.

  3. CT and MRI findings of Creutzfeldt-Jakob disease in the early stage. The usefulness of diffusion-weighted images

    International Nuclear Information System (INIS)

    Ukisu, Ryutaro; Kushihashi, Tamio; Gokan, Takehiko

    2001-01-01

    To detect subtle CT and MRI features of Creutzfeldt-Jacob disease (CJD) in the early stage is important to prevent a human-to-human transmission. This study included 10 patients of CJD who underwent CT and/or MRI in its early stage. CT, T1- and T2-weighted MRI, DWI, and FLAIR images were obtained in 10, 6, 4, and 2 patients respectively. On DWI, abnormal hyperintensities were observed in both cerebral cortex, and in basal ganglia in all patients. On FLAIR images, abnormal hyperintensies were observed in one patient. Detection of abnormal intensities may be possible in the early stage of CJD using MRI, particularly with DWI. (author)

  4. CT and MRI findings of Creutzfeldt-Jakob disease in the early stage. The usefulness of diffusion-weighted images

    Energy Technology Data Exchange (ETDEWEB)

    Ukisu, Ryutaro; Kushihashi, Tamio; Gokan, Takehiko [Showa Univ., Tokyo (Japan). School of Medicine] [and others

    2001-02-01

    To detect subtle CT and MRI features of Creutzfeldt-Jacob disease (CJD) in the early stage is important to prevent a human-to-human transmission. This study included 10 patients of CJD who underwent CT and/or MRI in its early stage. CT, T1- and T2-weighted MRI, DWI, and FLAIR images were obtained in 10, 6, 4, and 2 patients respectively. On DWI, abnormal hyperintensities were observed in both cerebral cortex, and in basal ganglia in all patients. On FLAIR images, abnormal hyperintensies were observed in one patient. Detection of abnormal intensities may be possible in the early stage of CJD using MRI, particularly with DWI. (author)

  5. Alterations in the inferior longitudinal fasciculus in autism and associations with visual processing: a diffusion-weighted MRI study.

    Science.gov (United States)

    Boets, Bart; Van Eylen, Lien; Sitek, Kevin; Moors, Pieter; Noens, Ilse; Steyaert, Jean; Sunaert, Stefan; Wagemans, Johan

    2018-01-01

    One of the most reported neural features of autism spectrum disorder (ASD) is the alteration of multiple long-range white matter fiber tracts, as assessed by diffusion-weighted imaging and indexed by reduced fractional anisotropy (FA). Recent methodological advances, however, have shown that this same pattern of reduced FA may be an artifact resulting from excessive head motion and poorer data quality and that aberrant structural connectivity in children with ASD is confined to the right inferior longitudinal fasciculus (ILF). This study aimed at replicating the observation of reduced FA along the right ILF in ASD, while controlling for group differences in head motion and data quality. In addition, we explored associations between reduced FA in the right ILF and quantitative ASD characteristics, and the involvement of the right ILF in visual processing, which is known to be altered in ASD. Global probabilistic tractography was performed on diffusion-weighted imaging data of 17 adolescent boys with ASD and 17 typically developing boys, matched for age, performance IQ, handedness, and data quality. Four tasks were administered to measure various aspects of visual information processing, together with questionnaires assessing ASD characteristics. Group differences were examined and the neural data were integrated with previously published findings using Bayesian statistics to quantify evidence for replication and to pool data and thus increase statistical power. (Partial) correlations were calculated to investigate associations between measures. The ASD group showed consistently reduced FA only in the right ILF and slower performance on the visual search task. Bayesian statistics pooling data across studies confirmed that group differences in FA were confined to the right ILF only, with the evidence for altered FA in the left ILF being indecisive. Lower FA in the right ILF tended to covary with slower visual search and a more fragmented part-oriented processing style

  6. The Role of Diffusion-Weighted MRI in Differentiation of Idiopathic Acute Transverse Myelitis and Acute Spinal Cord Infarction

    International Nuclear Information System (INIS)

    Kim, Yeo Goon; Lee, Joon Woo; Kim, Jae Hyoung; Kang, Heung Sik; Park, Kyung Seok

    2011-01-01

    To compare the diffusion characteristics of idiopathic acute transverse myelitis (ATM) and acute spinal cord infarction (SCI). Diffusion-weighted images (DWI) and an apparent diffusion coefficient (ADC) map were prospectively obtained from patients diagnosed with myelopathy between February 2006 and April 2009. Inclusion criteria included 1) the presence of an intramedullary T2-high signal intensity and 2) a final diagnosis of idiopathic ATM or SCI established by one neurologist. In total, 13 patients (M : F = 8 : 5; mean age, 39.5 years; range, 29-50 years) with idiopathic ATM and seven patients (M : F = 2 : 5; mean age, 58 years; range, 48-75 years) with SCI were included in this study. Two radiologists evaluated the DWIs and ADC map in consensus. The extent of the cord signal change was also evaluated on T2-weighted sagittal images. Among the 16 patients with ATM, 14 patients showed iso-signal on an ADC map, but one case showed restricted diffusion and another showed increased diffusion on the ADC map. Among the seven patients with SCI, five patients showed restricted diffusion. Idiopathic ATM usually does not demonstrate restricted diffusion, which can be a clue to differentiate it from SCI. However, idiopathic ATM with larger segment involvement can show focal diffusion restriction.

  7. Task-based evaluation of segmentation algorithms for diffusion-weighted MRI without using a gold standard

    International Nuclear Information System (INIS)

    Jha, Abhinav K; Kupinski, Matthew A; Rodríguez, Jeffrey J; Stephen, Renu M; Stopeck, Alison T

    2012-01-01

    In many studies, the estimation of the apparent diffusion coefficient (ADC) of lesions in visceral organs in diffusion-weighted (DW) magnetic resonance images requires an accurate lesion-segmentation algorithm. To evaluate these lesion-segmentation algorithms, region-overlap measures are used currently. However, the end task from the DW images is accurate ADC estimation, and the region-overlap measures do not evaluate the segmentation algorithms on this task. Moreover, these measures rely on the existence of gold-standard segmentation of the lesion, which is typically unavailable. In this paper, we study the problem of task-based evaluation of segmentation algorithms in DW imaging in the absence of a gold standard. We first show that using manual segmentations instead of gold-standard segmentations for this task-based evaluation is unreliable. We then propose a method to compare the segmentation algorithms that does not require gold-standard or manual segmentation results. The no-gold-standard method estimates the bias and the variance of the error between the true ADC values and the ADC values estimated using the automated segmentation algorithm. The method can be used to rank the segmentation algorithms on the basis of both the ensemble mean square error and precision. We also propose consistency checks for this evaluation technique. (paper)

  8. Diffusion-Weighted MRI in Creutzfeldt-Jakob Disease: Focus on the Cerebral Cortex and Chronologic Change

    International Nuclear Information System (INIS)

    Lee, Jeong Eun; Song, Chang Joon; Lee, In Ho; Yu, In Kyu; Choi, See Sung

    2010-01-01

    To evaluate high cortical signal intensity and chronologic changes for diffusion-weighted MR imaging (DWI) in sporadic Creutzfeldt-Jakob disease. We retrospectively analyzed the DWI results of 16 patients with probable CJD (according to WHO criteria) and evaluated the distribution, extent and bilaterality of the lesions in the cortex, basal ganglia and thalamus. We also reviewed the chronologic changes of the lesions by evaluating the followup MR examination results in 8 of 16 patients. Cortical abnormalities were present in 15 (94%) of 16 patients. Isolated cortical involvement was present in 6 patients (40%), while the combined involvement of the cortex and basal ganglia was present in 9 patients (60%). The distribution of the lesions was bilateral in 12 patients and predominantly on the right side in 8 patients. Upon follow-up MR imaging, the cortical lesions showed progress in terms of extent and signal intensity. Basal ganglia abnormalities were present in 9 of 15 patients. Moreover, 4 of 6 patients who had no abnormal signal intensity in the basal ganglia on the initial MR imaging results, showed abnormally high signal intensity upon follow-up MR imaging. The characteristically high cortical signal intensities on DWI in an elderly patient with rapidly progressive dementia should point to the diagnosis of early phase CJD and might be useful for the differential diagnosis

  9. Diffusion-Weighted MRI in Creutzfeldt-Jakob Disease: Focus on the Cerebral Cortex and Chronologic Change

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Eun; Song, Chang Joon; Lee, In Ho [Chungnam National University, Daejeon (Korea, Republic of); Yu, In Kyu [Eulji University Hospital, Seoul (Korea, Republic of); Choi, See Sung [Wonkwang University Hospital, Iksan (Korea, Republic of)

    2010-08-15

    To evaluate high cortical signal intensity and chronologic changes for diffusion-weighted MR imaging (DWI) in sporadic Creutzfeldt-Jakob disease. We retrospectively analyzed the DWI results of 16 patients with probable CJD (according to WHO criteria) and evaluated the distribution, extent and bilaterality of the lesions in the cortex, basal ganglia and thalamus. We also reviewed the chronologic changes of the lesions by evaluating the followup MR examination results in 8 of 16 patients. Cortical abnormalities were present in 15 (94%) of 16 patients. Isolated cortical involvement was present in 6 patients (40%), while the combined involvement of the cortex and basal ganglia was present in 9 patients (60%). The distribution of the lesions was bilateral in 12 patients and predominantly on the right side in 8 patients. Upon follow-up MR imaging, the cortical lesions showed progress in terms of extent and signal intensity. Basal ganglia abnormalities were present in 9 of 15 patients. Moreover, 4 of 6 patients who had no abnormal signal intensity in the basal ganglia on the initial MR imaging results, showed abnormally high signal intensity upon follow-up MR imaging. The characteristically high cortical signal intensities on DWI in an elderly patient with rapidly progressive dementia should point to the diagnosis of early phase CJD and might be useful for the differential diagnosis.

  10. Liver fibrosis: stretched exponential model outperforms mono-exponential and bi-exponential models of diffusion-weighted MRI.

    Science.gov (United States)

    Seo, Nieun; Chung, Yong Eun; Park, Yung Nyun; Kim, Eunju; Hwang, Jinwoo; Kim, Myeong-Jin

    2018-07-01

    To compare the ability of diffusion-weighted imaging (DWI) parameters acquired from three different models for the diagnosis of hepatic fibrosis (HF). Ninety-five patients underwent DWI using nine b values at 3 T magnetic resonance. The hepatic apparent diffusion coefficient (ADC) from a mono-exponential model, the true diffusion coefficient (D t ), pseudo-diffusion coefficient (D p ) and perfusion fraction (f) from a biexponential model, and the distributed diffusion coefficient (DDC) and intravoxel heterogeneity index (α) from a stretched exponential model were compared with the pathological HF stage. For the stretched exponential model, parameters were also obtained using a dataset of six b values (DDC # , α # ). The diagnostic performances of the parameters for HF staging were evaluated with Obuchowski measures and receiver operating characteristics (ROC) analysis. The measurement variability of DWI parameters was evaluated using the coefficient of variation (CoV). Diagnostic accuracy for HF staging was highest for DDC # (Obuchowski measures, 0.770 ± 0.03), and it was significantly higher than that of ADC (0.597 ± 0.05, p bi-exponential DWI model • Acquisition of six b values is sufficient to obtain accurate DDC and α.

  11. Tumor spatial heterogeneity in myxoid-containing soft tissue using texture analysis of diffusion-weighted MRI.

    Directory of Open Access Journals (Sweden)

    Hyun Su Kim

    Full Text Available The objective of this study was to examine the tumor spatial heterogeneity in myxoid-containing soft-tissue tumors (STTs using texture analysis of diffusion-weighted imaging (DWI. A total of 40 patients with myxoid-containing STTs (23 benign and 17 malignant were included in this study. The region of interest (ROI was manually drawn on the apparent diffusion coefficient (ADC map. For texture analysis, the global (mean, standard deviation, skewness, and kurtosis, regional (intensity variability and size-zone variability, and local features (energy, entropy, correlation, contrast, homogeneity, variance, and maximum probability were extracted from the ADC map. Student's t-test was used to test the difference between group means. Analysis of covariance (ANCOVA was performed with adjustments for age, sex, and tumor volume. The receiver operating characteristic (ROC analysis was performed to compare diagnostic performances. Malignant myxoid-containing STTs had significantly higher kurtosis (P = 0.040, energy (P = 0.034, correlation (P<0.001, and homogeneity (P = 0.003, but significantly lower contrast (P<0.001 and variance (P = 0.001 compared with benign myxoid-containing STTs. Contrast showed the highest area under the curve (AUC = 0.923, P<0.001, sensitivity (94.12%, and specificity (86.96%. Our results reveal the potential utility of texture analysis of ADC maps for differentiating benign and malignant myxoid-containing STTs.

  12. [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.

  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. Diffusion-weighted MRI of the Prostate: Advantages of Zoomed EPI with Parallel-transmit-accelerated 2D-selective Excitation Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Thierfelder, Kolja M.; Scherr, Michael K.; Weiss, Jakob; Mueller-Lisse, Ullrich G.; Theisen, Daniel [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Notohamiprodjo, Mike; Nikolaou, Konstantin [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); University Hospital Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Dietrich, Olaf [Ludwig-Maximilians-University Hospital Munich, Josef Lissner Laboratory for Biomedical Imaging, Institute for Clinical Radiology, Munich (Germany); Pfeuffer, Josef [Siemens Healthcare, Application Development, Erlangen (Germany)

    2014-12-15

    The purpose of our study was to evaluate the use of 2D-selective, parallel-transmit excitation magnetic resonance imaging (MRI) for diffusion-weighted echo-planar imaging (pTX-EPI) of the prostate, and to compare it to conventional, single-shot EPI (c-EPI). The MRI examinations of 35 patients were evaluated in this prospective study. PTX-EPI was performed with a TX-acceleration factor of 1.7 and a field of view (FOV) of 150 x 90 mm{sup 2}, whereas c-EPI used a full FOV of 380 x 297 mm{sup 2}. Two readers evaluated three different aspects of image quality on 5-point Likert scales. To quantify distortion artefacts, maximum diameters and prostate volume were determined for both techniques and compared to T2-weighted imaging. The zoomed pTX-EPI was superior to c-EPI with respect to overall image quality (3.39 ± 0.62 vs 2.45 ± 0.67) and anatomic differentiability (3.29 ± 0.65 vs 2.41 ± 0.65), each with p < 0.0001. Artefacts were significantly less severe in pTX-EPI (0.93 ± 0.73 vs 1.49 ± 1.08), p < 0.001. The quantitative analysis yielded a higher agreement of pTX-EPI with T2-weighted imaging than c-EPI with respect to coronal (ICCs: 0.95 vs 0.93) and sagittal (0.86 vs 0.73) diameters as well as prostate volume (0.94 vs 0.92). Apparent diffusion coefficient (ADC) values did not differ significantly between the two techniques (p > 0.05). Zoomed pTX-EPI leads to substantial improvements in diffusion-weighted imaging (DWI) of the prostate with respect to different aspects of image quality and severity of artefacts. (orig.)

  16. Diffusion measurement of intraplaque hemorrhage and intramural hematoma using diffusion weighted MRI at 3T in cervical artery

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Bin [The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi (China); Yang, Li [Fudan University, Department of Radiology, Shanghai Institute of Medical Imaging, Zhongshan Hospital, Shanghai (China); Wang, Guangbin; Shi, Honglu; Wang, Shanshan; Li, Huihua [Shandong University, Shandong Medical Imaging Research Institute, Jinan, Shandong (China); Chen, Weibo; Chan, Queenie [Philips Healthcare, Shanghai (China)

    2016-10-15

    To assess the difference between carotid haemorrhagic plaque and non-haemorrhagic plaque by using diffusion-weighted imaging (DWI) and to evaluate carotid intraplaque haemorrhage (IPH) and intramural hematoma (IMH) of cervical artery dissection with apparent diffusion coefficient (ADC) measurement. Fifty-one symptomatic patients underwent 3.0-T carotid MR imaging, including conventional sequences, three-dimensional (3D) magnetization-prepared rapid acquisition gradient-echo (MPRAGE) sequence, and DWI. Thirty-nine patients with carotid plaque and eight patients with IMH of cervical artery dissection were finally included. The groups of hemorrhagic plaque, non-hemorrhagic plaque and IMH were divided according to 3D MPRAGE sequence. ADC values of different groups were measured, and t tests were performed. The mean ADC values of hemorrhagic plaques, non-hemorrhagic plaque and IMH were (1.284 ± 0.327) x 10{sup -3}mm{sup 2}/s, (1.766 ± 0.477) x 10{sup -3}mm{sup 2}/s, and (0.563 ± 0.119) x 10{sup -3}mm{sup 2}/s, respectively. The mean ADC values of hemorrhagic and non-hemorrhagic regions in the hemorrhagic plaque group were (0.985 ± 0.376) x 10{sup -3}mm{sup 2}/s and (1.480 ± 0.465) x 10{sup -3}mm{sup 2}/s, respectively. The differences between the hemorrhagic plaque and non-hemorrhagic plaque, hemorrhagic region and non-hemorrhagic region in hemorrhagic plaque, and the hemorrhagic region in the hemorrhagic plaque and IMH of artery dissection were significant (P < 0.05). DWI may be a useful complement to conventional MR imaging for identifying haemorrhage of carotid plaques and differentiate IMHs from IPH. (orig.)

  17. Diffusion measurement of intraplaque hemorrhage and intramural hematoma using diffusion weighted MRI at 3T in cervical artery

    International Nuclear Information System (INIS)

    Yao, Bin; Yang, Li; Wang, Guangbin; Shi, Honglu; Wang, Shanshan; Li, Huihua; Chen, Weibo; Chan, Queenie

    2016-01-01

    To assess the difference between carotid haemorrhagic plaque and non-haemorrhagic plaque by using diffusion-weighted imaging (DWI) and to evaluate carotid intraplaque haemorrhage (IPH) and intramural hematoma (IMH) of cervical artery dissection with apparent diffusion coefficient (ADC) measurement. Fifty-one symptomatic patients underwent 3.0-T carotid MR imaging, including conventional sequences, three-dimensional (3D) magnetization-prepared rapid acquisition gradient-echo (MPRAGE) sequence, and DWI. Thirty-nine patients with carotid plaque and eight patients with IMH of cervical artery dissection were finally included. The groups of hemorrhagic plaque, non-hemorrhagic plaque and IMH were divided according to 3D MPRAGE sequence. ADC values of different groups were measured, and t tests were performed. The mean ADC values of hemorrhagic plaques, non-hemorrhagic plaque and IMH were (1.284 ± 0.327) x 10 -3 mm 2 /s, (1.766 ± 0.477) x 10 -3 mm 2 /s, and (0.563 ± 0.119) x 10 -3 mm 2 /s, respectively. The mean ADC values of hemorrhagic and non-hemorrhagic regions in the hemorrhagic plaque group were (0.985 ± 0.376) x 10 -3 mm 2 /s and (1.480 ± 0.465) x 10 -3 mm 2 /s, respectively. The differences between the hemorrhagic plaque and non-hemorrhagic plaque, hemorrhagic region and non-hemorrhagic region in hemorrhagic plaque, and the hemorrhagic region in the hemorrhagic plaque and IMH of artery dissection were significant (P < 0.05). DWI may be a useful complement to conventional MR imaging for identifying haemorrhage of carotid plaques and differentiate IMHs from IPH. (orig.)

  18. Multi-institutional validation of a novel textural analysis tool for preoperative stratification of suspected thyroid tumors on diffusion-weighted MRI.

    Science.gov (United States)

    Brown, Anna M; Nagala, Sidhartha; McLean, Mary A; Lu, Yonggang; Scoffings, Daniel; Apte, Aditya; Gonen, Mithat; Stambuk, Hilda E; Shaha, Ashok R; Tuttle, R Michael; Deasy, Joseph O; Priest, Andrew N; Jani, Piyush; Shukla-Dave, Amita; Griffiths, John

    2016-04-01

    Ultrasound-guided fine needle aspirate cytology fails to diagnose many malignant thyroid nodules; consequently, patients may undergo diagnostic lobectomy. This study assessed whether textural analysis (TA) could noninvasively stratify thyroid nodules accurately using diffusion-weighted MRI (DW-MRI). This multi-institutional study examined 3T DW-MRI images obtained with spin echo echo planar imaging sequences. The training data set included 26 patients from Cambridge, United Kingdom, and the test data set included 18 thyroid cancer patients from Memorial Sloan Kettering Cancer Center (New York, New York, USA). Apparent diffusion coefficients (ADCs) were compared over regions of interest (ROIs) defined on thyroid nodules. TA, linear discriminant analysis (LDA), and feature reduction were performed using the 21 MaZda-generated texture parameters that best distinguished benign and malignant ROIs. Training data set mean ADC values were significantly different for benign and malignant nodules (P = 0.02) with a sensitivity and specificity of 70% and 63%, respectively, and a receiver operator characteristic (ROC) area under the curve (AUC) of 0.73. The LDA model of the top 21 textural features correctly classified 89/94 DW-MRI ROIs with 92% sensitivity, 96% specificity, and an AUC of 0.97. This algorithm correctly classified 16/18 (89%) patients in the independently obtained test set of thyroid DW-MRI scans. TA classifies thyroid nodules with high sensitivity and specificity on multi-institutional DW-MRI data sets. This method requires further validation in a larger prospective study. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

  19. Q-ball imaging models: comparison between high and low angular resolution diffusion-weighted MRI protocols for investigation of brain white matter integrity

    Energy Technology Data Exchange (ETDEWEB)

    Caiazzo, Giuseppina; Trojsi, Francesca; Cirillo, Mario; Tedeschi, Gioacchino [MRI Research Center SUN-FISM-Neurological Institute for Diagnosis and Care ' ' Hermitage Capodimonte' ' , Naples (Italy); Second University of Naples, Department of Medical, Surgical, Neurological, Metabolic and Aging Sciences, Naples (Italy); Esposito, Fabrizio [University of Salerno, Department of Medicine and Surgery, Baronissi (Salerno) (Italy); Maastricht University, Department of Cognitive Neuroscience, Maastricht (Netherlands)

    2016-02-15

    Q-ball imaging (QBI) is one of the typical data models for quantifying white matter (WM) anisotropy in diffusion-weighted MRI (DwMRI) studies. Brain and spinal investigation by high angular resolution DwMRI (high angular resolution imaging (HARDI)) protocols exhibits higher angular resolution in diffusion imaging compared to low angular resolution models, although with longer acquisition times. We aimed to assess the difference between QBI-derived anisotropy values from high and low angular resolution DwMRI protocols and their potential advantages or shortcomings in neuroradiology. Brain DwMRI data sets were acquired in seven healthy volunteers using both HARDI (b = 3000 s/mm{sup 2}, 54 gradient directions) and low angular resolution (b = 1000 s/mm{sup 2}, 32 gradient directions) acquisition schemes. For both sequences, tract of interest tractography and generalized fractional anisotropy (GFA) measures were extracted by using QBI model and were compared between the two data sets. QBI tractography and voxel-wise analyses showed that some WM tracts, such as corpus callosum, inferior longitudinal, and uncinate fasciculi, were reconstructed as one-dominant-direction fiber bundles with both acquisition schemes. In these WM tracts, mean percent different difference in GFA between the two data sets was less than 5 %. Contrariwise, multidirectional fiber bundles, such as corticospinal tract and superior longitudinal fasciculus, were more accurately depicted by HARDI acquisition scheme. Our results suggest that the design of optimal DwMRI acquisition protocols for clinical investigation of WM anisotropy by QBI models should consider the specific brain target regions to be explored, inducing researchers to a trade-off choice between angular resolution and acquisition time. (orig.)

  20. Evaluation of short-term response of high intensity focused ultrasound ablation for primary hepatic carcinoma: Utility of contrast-enhanced MRI and diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yuanyuan; Zhao Jiannong [Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China); Guo Dajing, E-mail: guodaj@163.com [Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China); Zhong Weijia [Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China); Ran Lifen [Clinical Center for Tumor Therapy, Second Affiliated Hospital, Chongqing Medical University, No. 74 Linjiang Rd, Yuzhong District, Chongqing 400010 (China)

    2011-09-15

    Objective: To explore the significance of contrast-enhanced MRI (CE-MRI) and diffusion-weighted imaging (DWI) in evaluating the short-term response of high intensity focused ultrasound (HIFU) ablation for primary hepatic carcinoma (PHC). Methods: Thirty-nine lesions in the livers of 27 patients were performed HIFU ablation. Conventional MRI sequences, CE-MRI and DWI were performed 1 week before HIFU and 1 week, 3 months after the therapy, respectively. The short-term responses of HIFU for all lesions were evaluated with MRI. Results: 28 of the 39 lesions (28/39, 71.8%) showed complete necrosis with no enhancement 1 week and 3 months after HIFU. The apparent diffusion coefficient (ADC) values 1 week and 3 months after HIFU were significantly higher than those 1 week before treatment (p < 0.05). The tumor recurrence was detected in 7 of the 39 lesions (7/39, 17.9%) which had no significant enhancement 1 week after HIFU. On the 3 months follow-up, focal nodules were found on the inner aspects of the treated areas. The ADC values had no significant difference between 1 week before and after treatment (p > 0.05), however, they were significantly higher 3 months after HIFU (p < 0.05). The tumor residuals were detected in 4 of the 39 lesions (4/39, 10.3%) showing enhancement 1 week after treatment and increased size 3 months after HIFU. The ADC values had no significant difference among 1 week before HIFU, 1 week and 3 months after treatment (p > 0.05). Conclusion: CE-MRI and DWI can be employed to evaluate the short-term response of HIFU ablation for PHC and to guide the patient management.

  1. Disappearing or residual tiny (≤5 mm) colorectal liver metastases after chemotherapy on gadoxetic acid-enhanced liver MRI and diffusion-weighted imaging: Is local treatment required?

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Soo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Cheonan Hospital, Department of Radiology, Soonchunhyang University College of Medicine, Cheonan-si, Chungcheongnam-do (Korea, Republic of); Song, Kyoung Doo; Kim, Young Kon [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Hee Cheol; Huh, Jung Wook [Sungkyunkwan University School of Medicine, Department of Surgery, Samsung Medical Center, Seoul (Korea, Republic of); Park, Young Suk; Park, Joon Oh; Kim, Seung Tae [Sungkyunkwan University School of Medicine, Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Seoul (Korea, Republic of)

    2017-07-15

    To evaluate the clinical course of disappearing colorectal liver metastases (DLM) or residual tiny (≤5 mm) colorectal liver metastases (RTCLM) on gadoxetic acid-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in patients who had colorectal liver metastases (CLM) and received chemotherapy. Among 137 patients who received chemotherapy for CLM and underwent gadoxetic acid-enhanced MRI and DWI between 2010 and 2012, 43 patients with 168 DLMs and 48 RTCLMs were included. The cumulative in situ recurrence rate of DLM and progression rate of RTCLM and their predictive factors were evaluated. A total of 150 DLMs and 26 RTCLMs were followed up without additional treatment. At 1 and 2 years, respectively, the cumulative in situ recurrence rates for DLM were 10.9 % and 15.7 % and the cumulative progression rates for RTCLM were 27.2 % and 33.2 %. The in situ recurrence rate at 2 years was 4.9 % for the DLM group that did not show reticular hypointensity of liver parenchyma on hepatobiliary phase. DLM on gadoxetic acid-enhanced liver MRI and DWI indicates a high possibility of clinical complete response, especially in patients without chemotherapy-induced sinusoidal obstruction syndrome. Thirty-three percent of RTCLMs showed progression at 2 years. (orig.)

  2. Differentiation of benign and malignant lesions of the tongue by using diffusion-weighted MRI at 3.0 T.

    Science.gov (United States)

    Li, S; Cheng, J; Zhang, Y; Zhang, Z

    2015-01-01

    Diffusion-weighted MRI (DWI) has been introduced in head and neck lesions and adds important information to the findings obtained through conventional MRI. The purpose of this study was to assess the role of DWI in differentiating benign and malignant lesions of the tongue at 3.0-T field strength imaging. 78 patients with 78 lingual lesions underwent conventional MRI and DWI with b-values of 0 and 1000 s mm(-2) before therapy. The apparent diffusion coefficient (ADC) maps were reconstructed, and the ADC values of the lingual lesions were calculated and compared between benign and malignant lesions of the tongue. The mean ADC values of the malignant tumours, benign solid lesions and cystic lesions were (1.08±0.16)×10(-3), (1.68±0.33)×10(-3) and (2.21±0.35)×10(-3) mm2 s(-1), respectively. The mean ADC values of malignant tumours were significantly lower (pbenign and malignant lesions are significantly different at 3.0-T imaging. DWI can be applied as a complementary tool in the differentiation of benign and malignant lesions of the tongue.

  3. Preoperative prediction of sentinel lymph node metastasis in breast cancer based on radiomics of T2-weighted fat-suppression and diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yuhao; Mo, Xiaokai [Guangdong General Hospital/Guangdong Academy of Medical Sciences, Department of Radiology, Guangzhou, Guangdong Province (China); Shantou University Medical College, Graduate College, Shantou, Guangdong (China); Feng, Qianjin; Yang, Wei; Lu, Zixiao; Deng, Chunyan [Southern Medical University, The Guangdong Provincial Key Laboratory of Medical Image Processing, School of Biomedical Engineering, Guangzhou, Guangdong (China); Zhang, Lu; Lian, Zhouyang; Liu, Jing; Luo, Xiaoning; Pei, Shufang; Huang, Wenhui; Liang, Changhong; Zhang, Bin; Zhang, Shuixing [Guangdong General Hospital/Guangdong Academy of Medical Sciences, Department of Radiology, Guangzhou, Guangdong Province (China)

    2018-02-15

    To predict sentinel lymph node (SLN) metastasis in breast cancer patients using radiomics based on T{sub 2}-weighted fat suppression (T{sub 2}-FS) and diffusion-weighted MRI (DWI). We enrolled 146 patients with histologically proven breast cancer. All underwent pretreatment T{sub 2}-FS and DWI MRI scan. In all, 10,962 texture and four non-texture features were extracted for each patient. The 0.623 + bootstrap method and the area under the curve (AUC) were used to select the features. We constructed ten logistic regression models (orders of 1-10) based on different combination of image features using stepwise forward method. For T{sub 2}-FS, model 10 with ten features yielded the highest AUC of 0.847 in the training set and 0.770 in the validation set. For DWI, model 8 with eight features reached the highest AUC of 0.847 in the training set and 0.787 in the validation set. For joint T{sub 2}-FS and DWI, model 10 with ten features yielded an AUC of 0.863 in the training set and 0.805 in the validation set. Full utilisation of breast cancer-specific textural features extracted from anatomical and functional MRI images improves the performance of radiomics in predicting SLN metastasis, providing a non-invasive approach in clinical practice. (orig.)

  4. Comparison of abdominal MRI with diffusion-weighted imaging to {sup 68}Ga-DOTATATE PET/CT in detection of neuroendocrine tumors of the pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Schmid-Tannwald, Christine; Schmid-Tannwald, Christoph M.; Neumann, Ralph; Nikolaou, Konstantin; Schramm, Nicolai; Reiser, Maximilian F.; Rist, Carsten [Ludwig Maximilians University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Morelli, John N. [Scott and White Hospital Temple, Department of Radiology, Temple, TX (United States); Haug, Alexander R.; Jansen, Nathalie [Ludwig Maximilians University Hospital Munich, Department of Nuclear Medicine, Munich (Germany)

    2013-06-15

    The aim of the study was to evaluate contrast-enhanced MRI, diffusion-weighted MRI (DW MRI), and {sup 68}Ga-DOTATATE positron emission tomography (PET)/CT in the detection of intermediate to well-differentiated neuroendocrine tumors (NET) of the pancreas. Eighteen patients with pathologically proven pancreatic NET who underwent MRI including DW MRI and PET/CT within 6 weeks of each other were included in this retrospective study. Two radiologists evaluated T2-weighted (T2w), T2w + DW MRI, T2w + contrast-enhanced T1-weighted (CE T1w) MR images, and PET/CT for NET detection. The sensitivity and level of diagnostic confidence were compared among modalities using McNemar's test and a Wilcoxon signed rank test. Apparent diffusion coefficients (ADC) of pancreatic NETs and normal pancreatic tissue were compared with Student's t test. Of the NETs, 8/23 (34.8 %) and 9/23 (39.1 %) were detected on T2w images by observers 1 and 2, respectively. Detection rates improved significantly by combining T2w images with DW MRI (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05) or CE T1w images (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05). Detection rates of pancreatic NET with PET/CT (both observers: 23/23 = 100 %) were statistically significantly higher than with MRI (p < 0.05). The mean ADC value of NET (1.02 {+-} 0.26 x 10{sup -3} mm{sup 2}/s) was statistically significantly lower than that of normal pancreatic tissue (1.48 {+-} 0.39 x 10{sup -3} mm{sup 2}/s). DW MRI is a valuable adjunct to T2w imaging and comparable to CE T1w imaging in pancreatic NET detection, quantitatively differentiating between NET and normal pancreatic tissue with ADC measurements. {sup 68}Ga-DOTATATE PET/CT is more sensitive than MRI in the detection of pancreatic NET. (orig.)

  5. Diffusion-weighted MRI and fibroscan vs. histopathology for assessment of liver fibrosis in chronic HCV patients: (Pilot study

    Directory of Open Access Journals (Sweden)

    Ahmed Hosni Kamel Abdelmaksoud

    2015-06-01

    Conclusions: Diffusion MRI can distinguish non-fibrotic liver (F0 from advanced fibrosis (F3 and F4 but cannot be used to distinguish between the intermediate stages of fibrosis-fibroscan can differentiate between (F0, F1, F2 and (F3, F4.

  6. Diagnostic value of diffusion weighted MRI and ADC in differential diagnosis of cavernous hemangioma of the liver.

    Science.gov (United States)

    Tokgoz, Ozlem; Unlu, Ebru; Unal, Ilker; Serifoglu, Ismail; Oz, Ilker; Aktas, Elif; Caglar, Emrah

    2016-03-01

    To investigate the use of diffusion weighted magnetic resonance imaging (DWI) and the apparent diffusion coefficient (ADC) values in the diagnosis of hemangioma. The study population consisted of 72 patients with liver masses larger than 1 cm (72 focal lesions). DWI examination with a b value of 600 s/mm2 was carried out for all patients. After DWI examination, an ADC map was created and ADC values were measured for 72 liver masses and normal liver tissue (control group). The average ADC values of normal liver tissue and focal liver lesions, the "cut-off" ADC values, and the diagnostic sensitivity and specificity of the ADC map in diagnosing hemangioma, benign and malignant lesions were researched. Of the 72 liver masses, 51 were benign and 21 were malignant. Benign lesions comprised 38 hemangiomas and 13 simple cysts. Malignant lesions comprised 9 hepatocellular carcinomas, and 12 metastases. The highest ADC values were measured for cysts (3.782±0.53×10(-3) mm(2)/s) and hemangiomas (2.705±0.63×10(-3) mm(2)/s). The average ADC value of hemangiomas was significantly higher than malignant lesions and the normal control group (p<0.001). The average ADC value of cysts were significantly higher when compared to hemangiomas and normal control group (p<0.001). To distinguish hemangiomas from malignant liver lesions, the "cut-off" ADC value of 1.800×10(-3) mm(2)/s had a sensitivity of 97.4% and a specificity of 90.9%. To distinguish hemangioma from normal liver parenchyma the "cut-off" value of 1.858×10(-3) mm(2)/s had a sensitivity of 97.4% and a specificity of 95.7%. To distinguish benign liver lesions from malignant liver lesions the "cut-off" value of 1.800×10(-3) mm(2)/s had a sensitivity of 96.1% and a specificity of 90.0%. DWI and quantitative measurement of ADC values can be used in differential diagnosis of benign and malignant liver lesions and also in the diagnosis and differentiation of hemangiomas. When dynamic examination cannot distinguish cases with

  7. Local recurrence of squamous cell carcinoma of the head and neck after radio(chemo)therapy: Diagnostic performance of FDG-PET/MRI with diffusion-weighted sequences.

    Science.gov (United States)

    Becker, Minerva; Varoquaux, Arthur D; Combescure, Christophe; Rager, Olivier; Pusztaszeri, Marc; Burkhardt, Karim; Delattre, Bénédicte M A; Dulguerov, Pavel; Dulguerov, Nicolas; Katirtzidou, Eirini; Caparrotti, Francesca; Ratib, Osman; Zaidi, Habib; Becker, Christoph D

    2018-02-01

    To determine the diagnostic performance of FDG-PET/MRI with diffusion-weighted imaging (FDG-PET/DWIMRI) for detection and local staging of head and neck squamous cell carcinoma (HNSCC) after radio(chemo)therapy. This was a prospective study that included 74 consecutive patients with previous radio(chemo)therapy for HNSCC and in whom tumour recurrence or radiation-induced complications were suspected clinically. The patients underwent hybrid PET/MRI examinations with morphological MRI, DWI and FDG-PET. Experienced readers blinded to clinical/histopathological data evaluated images according to established diagnostic criteria taking into account the complementarity of multiparametric information. The standard of reference was histopathology with whole-organ sections and follow-up ≥24 months. Statistical analysis considered data clustering. The proof of diagnosis was histology in 46/74 (62.2%) patients and follow-up (mean ± SD = 34 ± 8 months) in 28/74 (37.8%). Thirty-eight patients had 43 HNSCCs and 46 patients (10 with and 36 without tumours) had 62 benign lesions/complications. Sensitivity, specificity, and positive and negative predictive value of PET/DWIMRI were 97.4%, 91.7%, 92.5% and 97.1% per patient, and 93.0%, 93.5%, 90.9%, and 95.1% per lesion, respectively. Agreement between imaging-based and pathological T-stage was excellent (kappa = 0.84, p recurrence. • Prospective one-centre study showed excellent agreement between imaging-based and pathological T-stage. • 97.5% of positive concordant MRI, DWI and FDG-PET results correspond to recurrence. • 87% of discordant MRI, DWI and FDG-PET results correspond to benign lesions. • Multiparametric FDG-PET/DWIMRI facilitates planning of salvage surgery in the irradiated neck.

  8. Upper abdominal gadoxetic acid-enhanced and diffusion-weighted MRI for the detection of gastric cancer: Comparison with two-dimensional multidetector row CT

    International Nuclear Information System (INIS)

    Jang, K.M.; Kim, S.H.; Lee, S.J.; Lee, M.W.; Choi, D.; Kim, K.M.

    2014-01-01

    Aim: To evaluate the diagnostic performance of abdominal magnetic resonance imaging (MRI) for the detection of gastric cancer in comparison with that of two-dimensional (2D) multidetector row computed tomography (CT). Materials and methods: The study included 189 patients with 170 surgically confirmed gastric cancers and 19 patients without gastric cancer, all of whom underwent gadoxetic acid-enhanced MRI with diffusion-weighted (DW) imaging, and multidetector contrast-enhanced abdominal CT imaging. Two observers independently analysed three sets of images (CT set, conventional MRI set, and combined conventional and DW MRI set). A five-point scale for likelihood of gastric cancer was used. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were evaluated. Quantitative [apparent diffusion coefficient (ADC) analyses with Mann–Whitney U-test were conducted for gastric cancers and the nearby normal gastric wall. Results: The diagnostic accuracy and sensitivity for detection of gastric cancer were significantly higher on combined conventional and DW MRI set (77.8–78.3%; 75.3–75.9%) than the CT imaging set (67.7–71.4%; 64.1–68.2%) or the conventional MRI set (72–73%; 68.8–70%; p < 0.01). In particular, for gastric cancers with pT2 and pT3, the combined conventional and DW MRI set (91.6–92.6%) yielded significantly higher sensitivity for detection of gastric cancer than did the CT imaging set (76.8–81.1%) by both observers (p < 0.01). The mean ADC of gastric cancer lesions (1 ± 0.23 × 10 −3 mm 2 /s) differed significantly from that of normal gastric wall (1.77 ± 0.25 × 10 −3  mm 2 /s; p < 0.01). Conclusion: Abdominal MRI with DW imaging was more sensitive for the detection of gastric cancer than 2D-multidetector row CT or conventional MRI alone. - Highlights: • The sensitivity for detection of gastric cancer is high on abdominal MR imaging. • DW imaging is helpful for

  9. Increasing the Accuracy of Volume and ADC Delineation for Heterogeneous Tumor on Diffusion-Weighted MRI: Correlation with PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Nan-Jie [Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong (China); Wong, Chun-Sing, E-mail: drcswong@gmail.com [Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong (China); Chu, Yiu-Ching [Department of Radiology, Kwong Wah Hospital, Hong Kong (China); Guo, Hua [Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing (China); Huang, Bingsheng [Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong (China); Chan, Queenie [Philips Healthcare, Hong Kong (China)

    2013-10-01

    Purpose: To improve the accuracy of volume and apparent diffusion coefficient (ADC) measurements in diffusion-weighted magnetic resonance imaging (MRI), we proposed a method based on thresholding both the b0 images and the ADC maps. Methods and Materials: In 21 heterogeneous lesions from patients with metastatic gastrointestinal stromal tumors (GIST), gross lesion were manually contoured, and corresponding volumes and ADCs were denoted as gross tumor volume (GTV) and gross ADC (ADC{sub g}), respectively. Using a k-means clustering algorithm, the probable high-cellularity tumor tissues were selected based on b0 images and ADC maps. ADC and volume of the tissues selected using the proposed method were denoted as thresholded ADC (ADC{sub thr}) and high-cellularity tumor volume (HCTV), respectively. The metabolic tumor volume (MTV) in positron emission tomography (PET)/computed tomography (CT) was measured using 40% maximum standard uptake value (SUV{sub max}) as the lower threshold, and corresponding mean SUV (SUV{sub mean}) was also measured. Results: HCTV had excellent concordance with MTV according to Pearson's correlation (r=0.984, P<.001) and linear regression (slope = 1.085, intercept = −4.731). In contrast, GTV overestimated the volume and differed significantly from MTV (P=.005). ADC{sub thr} correlated significantly and strongly with SUV{sub mean} (r=−0.807, P<.001) and SUV{sub max} (r=−0.843, P<.001); both were stronger than those of ADC{sub g}. Conclusions: The proposed lesion-adaptive semiautomatic method can help segment high-cellularity tissues that match hypermetabolic tissues in PET/CT and enables more accurate volume and ADC delineation on diffusion-weighted MR images of GIST.

  10. Diffusion-weighted MRI of the prostate at 3.0 T: comparison of endorectal coil (ERC) MRI and phased-array coil (PAC) MRI-The impact of SNR on ADC measurement.

    Science.gov (United States)

    Mazaheri, Yousef; Vargas, H Alberto; Nyman, Gregory; Shukla-Dave, Amita; Akin, Oguz; Hricak, Hedvig

    2013-10-01

    To compare ADC values measured from diffusion-weighted MR (DW-MR) images of the prostate obtained with both endorectal and phased-array coils (ERC+PAC) to those from DW-MRI images obtained with an eight-channel torso phased-array coil (PAC) at 3.0 T. The institutional review board issued a waiver of informed consent for this HIPAA-compliant study. Twenty-five patients with biopsy-proven prostate cancer underwent standard 3-T MRI using 2 different coil arrangements (ERC+PAC and PAC only) in the same session. DW-MRI at five b-values (0, 600, 1000, 1200, and 1500 s/mm(2)) were acquired using both coil arrangements. On b=0 images, signal-to-noise ratios (SNRs) were measured as the ratio of the mean signal from PZ and TZ ROIs to the standard deviation from the mean signal in an artifact-free ROI in the rectum. Matching regions-of-interest (ROIs) were identified in the peripheral zone and transition zone on ERC-MRI and PAC-MRI. For each ROI, mean ADC values for all zero and non-zero b-value combinations were computed. Mean SNR with ERC-MRI at PZ (66.33 ± 27.07) and TZ (32.69 ± 12.52) was 9.27 and 5.52 times higher than with PAC-MRI ((7.32 ± 2.30) and (6.13 ± 1.56), respectively) (PERC-MRI (PERC. To address these requirements, clinical MR systems should have image processing capabilities which incorporate the noise distribution. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. Is there a role for conventional MRI and MR diffusion-weighted imaging for distinction of skull base chordoma and chondrosarcoma?

    Science.gov (United States)

    Müller, Uta; Kubik-Huch, Rahel A; Ares, Carmen; Hug, Eugen B; Löw, Roland; Valavanis, Antonios; Ahlhelm, Frank J

    2016-02-01

    Chordoma and chondrosarcoma are locally invasive skull base tumors with similar clinical symptoms and anatomic imaging features as reported in the literature. To determine differentiation of chordoma and chondrosarcoma of the skull base with conventional magnetic resonance imaging (cMRI) and diffusion-weighted MR imaging (DWI) in comparison to histopathological diagnosis. This retrospective study comprised 96 (chordoma, n = 64; chondrosarcoma, n = 32) patients with skull base tumors referred to the Paul Scherrer Institute (PSI) for proton therapy. cMRI signal intensities of all tumors were investigated. In addition, median apparent diffusion coefficient (ADC) values were measured in a subgroup of 19 patients (chordoma, n = 11; chondrosarcoma, n = 8). The majority 81.2% (26/32) of chondrosarcomas displayed an off-midline growth pattern, 18.8% (6/32) showed clival invasion, 18.8% (6/32) were located more centrally. Only 4.7% (3/64) of chordomas revealed a lateral clival origin. Using cMRI no significant differences in MR signal intensities were observed in contrast to significantly different ADC values (subgroup of 19/96 patients examined by DWI), with the highest mean value of 2017.2 × 10(-6 )mm(2)/s (SD, 139.9( )mm(2)/s) for chondrosarcoma and significantly lower value of 1263.5 × 10(-6 )mm(2)/s (SD, 100.2 × 10(-6 )mm(2)/s) for chordoma (P = 0.001/median test). An off-midline growth pattern can differentiate chondrosarcoma from chordoma on cMRI in a majority of patients. Additional DWI is a promising tool for the differentiation of these skull base tumors. © The Foundation Acta Radiologica 2015.

  12. Additional value of diffusion-weighted imaging to evaluate multifocal and multicentric breast cancer detected using pre-operative breast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Eun; Park, Eun Kyung; Cho, Kyu Ran; Cho, Sung Bum [Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seo, Bo Kyoung [Korea University Ansan Hospital, Korea University College of Medicine, Department of Radiology, Ansan (Korea, Republic of); Woo, Ok Hee [Korea University Guro Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Jung, Seung Pil [Korea University Anam Hospital, Korea University College of Medicine, Department of Surgery, Seoul (Korea, Republic of)

    2017-11-15

    To investigate whether diffusion-weighted imaging (DWI) aids pre-operative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to evaluate additional lesions in breast cancer patients. DCE-MRI and DWI were performed on 131 lesions, with available histopathological results. The apparent diffusion coefficient (ADC) of each lesion was measured, and the cut-off value for differentiation between malignant and benign lesions was calculated. A protocol combining the ADC cut-off value with DCE-MRI was validated in a cohort of 107 lesions in 77 patients. When an ADC cut-off value of 1.11 x 10{sup -3} mm{sup 2}/s from the development cohort was applied to the additional lesions in the validation cohort, the specificity increased from 18.9% to 67.6% (P < 0.001), and the diagnostic accuracy increased from 61.7% to 82.2% (P = 0.05), without significant loss of sensitivity (98.6% vs. 90.0%, P = 0.07). The negative predictive values of lesions in the same quadrant had decreased, as had those of lesions ≥1 cm in diameter. The ADC cut-off value in the validation cohort was 1.05 x 10{sup -3} mm{sup 2}/s. Additional implementation of DWI for breast lesions in pre-operative MRI can help to obviate unnecessary biopsies by increasing specificity. However, to avoid missing cancers, clinicians should closely monitor lesions located in the same quadrant or lesions ≥1 cm. (orig.)

  13. Diffusion-weighted imaging in relation to morphology on dynamic contrast enhancement MRI. The diagnostic value of characterizing non-puerperal mastitis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lina; Chu, Jianguo; Zhang, Weisheng; Liu, Ailian; Song, Qingwei [First Affiliated Hospital of Dalian Medical University, Department of Radiology, Dalian, Liaoning (China); Hu, Jiani; Guys, Nicholas [Wayne State University, Department of Radiology, Detroit, MI (United States); Meng, Jinli [Chengban Branch of West China Hospital, Department of Radiology, Chengdu, Sichuan (China); Wang, Shaowu [Second Affiliated Hospital of Dalian Medical University, Department of Radiology, Dalian, Liaoning (China)

    2018-03-15

    To demonstrate the value of diffusion-weighted imaging (DWI) in the characterisation of mastitis lesions. Sixty-one non-puerperal patients with pathologically confirmed single benign mastitis lesions underwent preoperative examinations with conventional MRI and axial DWI. Patients were categorised into three groups: (1) periductal mastitis (PDM), (2) granulomatous lobular mastitis (GLM), and (3) infectious abscess (IAB). Apparent diffusion coefficient (ADC) values of each lesion were recorded. A one-way ANOVA with logistic analysis was performed to compare ADC values and other parameters. Discriminative abilities of DWI modalities were compared using the area under the receiver operating characteristic curve (AUC). P < 0.05 was considered statistically significant. ADC values differed significantly among the three groups (P = 0.003) as well as between PDM and IAB and between PDM and GLM. The distribution of non-mass enhancement on dynamic contrast-enhanced (DCE) MRI differed significantly among the three groups (P = 0.03) but not between any two groups specifically. There were no differences in lesion location, patient age, T{sub 2}WI or DWI signal intensity, enhancement type, non-mass internal enhancement, or mass enhancement characteristics among the three groups. ADC values and the distribution of non-mass enhancement are valuable in classifying mastitis subtypes. (orig.)

  14. Comparison of non-Gaussian and Gaussian diffusion models of diffusion weighted imaging of rectal cancer at 3.0 T MRI.

    Science.gov (United States)

    Zhang, Guangwen; Wang, Shuangshuang; Wen, Didi; Zhang, Jing; Wei, Xiaocheng; Ma, Wanling; Zhao, Weiwei; Wang, Mian; Wu, Guosheng; Zhang, Jinsong

    2016-12-09

    Water molecular diffusion in vivo tissue is much more complicated. We aimed to compare non-Gaussian diffusion models of diffusion-weighted imaging (DWI) including intra-voxel incoherent motion (IVIM), stretched-exponential model (SEM) and Gaussian diffusion model at 3.0 T MRI in patients with rectal cancer, and to determine the optimal model for investigating the water diffusion properties and characterization of rectal carcinoma. Fifty-nine consecutive patients with pathologically confirmed rectal adenocarcinoma underwent DWI with 16 b-values at a 3.0 T MRI system. DWI signals were fitted to the mono-exponential and non-Gaussian diffusion models (IVIM-mono, IVIM-bi and SEM) on primary tumor and adjacent normal rectal tissue. Parameters of standard apparent diffusion coefficient (ADC), slow- and fast-ADC, fraction of fast ADC (f), α value and distributed diffusion coefficient (DDC) were generated and compared between the tumor and normal tissues. The SEM exhibited the best fitting results of actual DWI signal in rectal cancer and the normal rectal wall (R 2  = 0.998, 0.999 respectively). The DDC achieved relatively high area under the curve (AUC = 0.980) in differentiating tumor from normal rectal wall. Non-Gaussian diffusion models could assess tissue properties more accurately than the ADC derived Gaussian diffusion model. SEM may be used as a potential optimal model for characterization of rectal cancer.

  15. Cost-effectiveness of response evaluation after chemoradiation in patients with advanced oropharyngeal cancer using 18F-FDG-PET-CT and/or diffusion-weighted MRI.

    Science.gov (United States)

    Greuter, Marjolein Je; Schouten, Charlotte S; Castelijns, Jonas A; de Graaf, Pim; Comans, Emile Fi; Hoekstra, Otto S; de Bree, Remco; Coupé, Veerle Mh

    2017-04-11

    Considerable variation exists in diagnostic tests used for local response evaluation after chemoradiation in patients with advanced oropharyngeal cancer. The yield of invasive examination under general anesthesia (EUA) with biopsies in all patients is low and it may induce substantial morbidity. We explored four response evaluation strategies to detect local residual disease in terms of diagnostic accuracy and cost-effectiveness. We built a decision-analytic model using trial data of forty-six patients and scientific literature. We estimated for four strategies the proportion of correct diagnoses, costs concerning diagnostic instruments and the proportion of unnecessary EUA indications. Besides a reference strategy, i.e. EUA for all patients, we considered three imaging strategies consisting of 18 FDG-PET-CT, diffusion-weighted MRI (DW-MRI), or both 18 FDG-PET-CT and DW-MRI followed by EUA after a positive test. The impact of uncertainty was assessed in sensitivity analyses. The EUA strategy led to 96% correct diagnoses. Expected costs were €468 per patient whereas 89% of EUA indications were unnecessary. The DW-MRI strategy was the least costly strategy, but also led to the lowest proportion of correct diagnoses, i.e. 93%. The PET-CT strategy and combined imaging strategy were dominated by the EUA strategy due to respectively a smaller or equal proportion of correct diagnoses, at higher costs. However, the combination of PET-CT and DW-MRI had the highest sensitivity. All imaging strategies considerably reduced (unnecessary) EUA indications and its associated burden compared to the EUA strategy. Because the combined PET-CT and DW-MRI strategy costs only an additional €927 per patient, it is preferred over immediate EUA since it reaches the same diagnostic accuracy in detecting local residual disease while leading to substantially less unnecessary EUA indications. However, if healthcare resources are limited, DW-MRI is the strategy of choice because of lower

  16. Local recurrence of squamous cell carcinoma of the head and neck after radio(chemo)therapy. Diagnostic performance of FDG-PET/MRI with diffusion-weighted sequences

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Minerva; Varoquaux, Arthur D.; Rager, Olivier; Delattre, Benedicte M.A.; Katirtzidou, Eirini; Ratib, Osman; Zaidi, Habib; Becker, Christoph D. [Geneva University Hospitals (Switzerland). Div. of Radiology and Nuclear Medicine; Combescure, Christophe [Geneva University Hospitals (Switzerland). Centre for Clinical Research; Pusztaszeri, Marc; Burkhardt, Karim [Geneva University Hospitals (Switzerland). Div. of Clinical Pathology; Dulguerov, Pavel; Dulguerov, Nicolas [Geneva University Hospitals (Switzerland). Clinic of Otorhinolaryngology Head and Neck Surgery; Caparrotti, Francesca [Geneva University Hospitals (Switzerland). Div. of Radiation Oncology

    2018-02-15

    To determine the diagnostic performance of FDG-PET/MRI with diffusion-weighted imaging (FDG-PET/DWIMRI) for detection and local staging of head and neck squamous cell carcinoma (HNSCC) after radio(chemo)therapy. This was a prospective study that included 74 consecutive patients with previous radio(chemo)therapy for HNSCC and in whom tumour recurrence or radiation-induced complications were suspected clinically. The patients underwent hybrid PET/MRI examinations with morphological MRI, DWI and FDG-PET. Experienced readers blinded to clinical/histopathological data evaluated images according to established diagnostic criteria taking into account the complementarity of multiparametric information. The standard of reference was histopathology with whole-organ sections and follow-up ≥24 months. Statistical analysis considered data clustering. The proof of diagnosis was histology in 46/74 (62.2%) patients and follow-up (mean ± SD = 34 ± 8 months) in 28/74 (37.8%). Thirty-eight patients had 43 HNSCCs and 46 patients (10 with and 36 without tumours) had 62 benign lesions/complications. Sensitivity, specificity, and positive and negative predictive value of PET/DWIMRI were 97.4%, 91.7%, 92.5% and 97.1% per patient, and 93.0%, 93.5%, 90.9%, and 95.1% per lesion, respectively. Agreement between imaging-based and pathological T-stage was excellent (kappa = 0.84, p < 0.001). FDG-PET/DWIMRI yields excellent results for detection and T-classification of HNSCC after radio(chemo)therapy. (orig.)

  17. Quantitative evaluation of the tibial tunnel after anterior cruciate ligament reconstruction using diffusion weighted and dynamic contrast enhanced MRI: a follow-up feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Rupreht, Mitja; Seruga, Tomaz; Jevsek, Marko [University Medical Centre Maribor, Radiology Department, Maribor (Slovenia); Jevtic, Vladimir [University of Ljubljana, Medical Faculty, Ljubljana (Slovenia); Sersa, Igor [Jozef Stefan Institute, MRI Laboratory, Ljubljana (Slovenia); Vogrin, Matjaz [University of Medical Centre of Maribor, Department of Orthopaedics, Maribor (Slovenia)

    2012-05-15

    The aim of the study was to evaluate the feasibility of two quantitative MRI methods: diffusion weighted imaging (DWI) and dynamic contrast enhanced imaging (DCEI), for follow-up assessment of the tibial tunnel after reconstruction of the anterior cruciate ligament (ACL). Twenty-three patients were examined by MRI at 1 and 6 months following ACL reconstruction. DWI and DCEI were utilized for evaluating the region of interest (ROI) within the proximal part of the tibial tunnel. From the resulting apparent diffusion coefficient (ADC) maps, ADC values were calculated. DCEI data were used to extract the enhancement factor (f{sub enh}) and the enhancement gradient (g{sub enh}) for the same ROI. Calculated ADC as well as the f{sub enh} and g{sub enh} had diminished to a statistically significant extent by 6 months after ACL reconstruction. The average ADC value diminished from 1.48 (10{sup -3} mm{sup 2}/s) at 1 month to 1.30 (10{sup -3} mm{sup 2}/s) at 6 months after reconstruction. The average f{sub enh} value decreased from 1.21 at 1 month to 0.50 at 6 months and the average g{sub enh} value decreased from 2.01%/s to 1.15%/s at 6 months, respectively. The study proved feasibility of DWI and DCEI for quantitative assessment of the tibial tunnel at 1 and 6 months after ACL reconstruction. Both methods have the potential for use as an additional tool in the evaluation of new methods of ACL reconstruction. To our knowledge, this is the first time quantitative MRI has been used in the follow-up to the ACL graft healing process. (orig.)

  18. Novel use of non-echo-planar diffusion weighted MRI in monitoring disease activity and treatment response in active Grave's orbitopathy: An initial observational cohort study.

    Science.gov (United States)

    Lingam, Ravi Kumar; Mundada, Pravin; Lee, Vickie

    2018-01-10

    To examine the novel use of non-echo-planar diffusion weighted MRI (DWI) in depicting activity and treatment response in active Grave's orbitopathy (GO) by assessing, with inter-observer agreement, for a correlation between its apparent diffusion coefficients (ADCs) and conventional Short tau Inversion Recovery (STIR) MRI signal-intensity ratios (SIRs). A total of 23 actively inflamed muscles and 30 muscle response episodes were analysed in patients with active GO who underwent medical treatment. The MRI orbit scans included STIR sequences and non-echo-planar DWI were evaluated. Two observers independently assessed the images qualitatively for the presence of activity in the extraocular muscles (EOMs) and recorded the STIR signal-intensity (SI), SIR (SI ratio of EOM/temporalis muscle), and ADC values of any actively inflamed muscle on the pre-treatment scans and their corresponding values on the subsequent post-treatment scans. Inter-observer agreement was examined. There was a significant positive correlation (0.57, p < 0.001) between ADC and both SIR and STIR SI of the actively inflamed EOM. There was also a significant positive correlation (0.75, p < 0.001) between SIR and ADC values depicting change in muscle activity associated with treatment response. There was good inter-observer agreement. Our preliminary results indicate that quantitative evaluation with non-echo-planar DWI ADC values correlates well with conventional STIR SIR in detecting active GO and monitoring its treatment response, with good inter-observer agreement.

  19. Apparent diffusion coefficient of vertebral haemangiomas allows differentiation from malignant focal deposits in whole-body diffusion-weighted MRI

    International Nuclear Information System (INIS)

    Winfield, Jessica M.; Blackledge, Matthew D.; Collins, David J.; Tunariu, Nina; Messiou, Christina; Poillucci, Gabriele; Shah, Vallari; Kaiser, Martin F.

    2018-01-01

    The aim of this study was to identify apparent diffusion coefficient (ADC) values for typical haemangiomas in the spine and to compare them with active malignant focal deposits. This was a retrospective single-institution study. Whole-body magnetic resonance imaging (MRI) scans of 106 successive patients with active multiple myeloma, metastatic prostate or breast cancer were analysed. ADC values of typical vertebral haemangiomas and malignant focal deposits were recorded. The ADC of haemangiomas (72 ROIs, median ADC 1,085 x 10 -6 mm 2 s -1 , interquartile range 927-1,295 x 10 -6 mm 2 s -1 ) was significantly higher than the ADC of malignant focal deposits (97 ROIs, median ADC 682 x 10 -6 mm 2 s -1 , interquartile range 583-781 x 10 -6 mm 2 s -1 ) with a p-value < 10 -6 . Receiver operating characteristic (ROC) analysis produced an area under the curve of 0.93. An ADC threshold of 872 x 10 -6 mm 2 s -1 separated haemangiomas from malignant focal deposits with a sensitivity of 84.7 % and specificity of 91.8 %. ADC values of classical vertebral haemangiomas are significantly higher than malignant focal deposits. The high ADC of vertebral haemangiomas allows them to be distinguished visually and quantitatively from active sites of disease, which show restricted diffusion. (orig.)

  20. Analysis of the utility of diffusion-weighted MRI and apparent diffusion coefficient values in distinguishing central nervous system toxoplasmosis from lymphoma

    International Nuclear Information System (INIS)

    Schroeder, Paul C.; Donovan Post, M. Judith; Bruce-Gregorios, Jocelyn; Oschatz, Elizabeth; Stadler, Alfred; Thurnher, Majda M.

    2006-01-01

    Toxoplasmosis and lymphoma are common lesions of the central nervous system in patients with AIDS. It is often difficult to distinguish between these lesions both clinically and radiographically. Previous research has demonstrated restricted diffusion within cerebral lymphomas and bacterial abscesses. However, little work has been done to evaluate the diffusion characteristics of toxoplasmosis lesions. This study was designed to explore further the utility of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps and values in making the distinction between toxoplasmosis and lymphoma. The magnetic resonance imaging (MRI) studies of 36 patients, including 22 with toxoplasmosis (all of whom had AIDS) and 14 with lymphoma (8 of whom had AIDS), at two institutions were reviewed retrospectively. The characteristics of the lesions on DWI were evaluated, and the ADC ratios of the lesions were calculated and compared. There was significant overlap of the ADC ratios of toxoplasma and lymphoma, most notably in the intermediate (1.0-1.6) range. There was variability in ADC ratios even among different lesions in the same patient. In only a minority of the lymphoma patients were the ADC ratios low enough to suggest the correct diagnosis. Our study showed that toxoplasmosis exhibits a wide spectrum of diffusion characteristics with ADC ratios which have significant overlap with those of lymphoma. Therefore, in the majority of patients, ADC ratios are not definitive in making the distinction between toxoplasmosis and lymphoma. (orig.)

  1. Analysis of the utility of diffusion-weighted MRI and apparent diffusion coefficient values in distinguishing central nervous system toxoplasmosis from lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Paul C.; Donovan Post, M. Judith; Bruce-Gregorios, Jocelyn [University of Miami, Jackson Memorial Hospital, Miami, FL (United States); Oschatz, Elizabeth; Stadler, Alfred; Thurnher, Majda M. [Medical University of Vienna, Department of Radiology Neuroradiology Section, Vienna (Austria)

    2006-10-15

    Toxoplasmosis and lymphoma are common lesions of the central nervous system in patients with AIDS. It is often difficult to distinguish between these lesions both clinically and radiographically. Previous research has demonstrated restricted diffusion within cerebral lymphomas and bacterial abscesses. However, little work has been done to evaluate the diffusion characteristics of toxoplasmosis lesions. This study was designed to explore further the utility of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps and values in making the distinction between toxoplasmosis and lymphoma. The magnetic resonance imaging (MRI) studies of 36 patients, including 22 with toxoplasmosis (all of whom had AIDS) and 14 with lymphoma (8 of whom had AIDS), at two institutions were reviewed retrospectively. The characteristics of the lesions on DWI were evaluated, and the ADC ratios of the lesions were calculated and compared. There was significant overlap of the ADC ratios of toxoplasma and lymphoma, most notably in the intermediate (1.0-1.6) range. There was variability in ADC ratios even among different lesions in the same patient. In only a minority of the lymphoma patients were the ADC ratios low enough to suggest the correct diagnosis. Our study showed that toxoplasmosis exhibits a wide spectrum of diffusion characteristics with ADC ratios which have significant overlap with those of lymphoma. Therefore, in the majority of patients, ADC ratios are not definitive in making the distinction between toxoplasmosis and lymphoma. (orig.)

  2. Is quantitative diffusion-weighted MRI a valuable technique for the detection of changes in kidneys after extracorporeal shock wave lithotripsy?

    Science.gov (United States)

    Hocaoglu, Elif; Inci, Ercan; Aydin, Sibel; Cesme, Dilek Hacer; Kalfazade, Nadir

    2015-01-01

    Objective The aim of this study was to evaluate the capability and the reliability of diffusion-weighted imaging (DWI) in the changes of kidneys occurring after extracorporeal shock wave lithotripsy (ESWL) treatment for renal stones. Materials and Methods A total of 32 patients who underwent ESWL treatment for renal stone disease between June and December 2011 were enrolled in this prospective study. Color Doppler ultrasonography (CDUS) and DWI were performed before and within 24 hours after ESWL. DWI was obtained with b factors of 0, 500 and 1000 s/mm2 at 1.5 T MRI. Each of Resistive index (RI) and ADC values were calculated from the three regions of renal upper, middle and lower zones for both of the affected and contralateral kidneys. Paired sample t test was used for statistical analyses. Results After ESWL, the treated kidneys had statistically significant lower ADC values in all different regions compared with previous renal images. The best discriminative parameter was signal intensity with a b value of 1000 s/mm2. The changes of DWI after ESWL were noteworthy in the middle of the treated kidney (pESWL (p>0.05). Conclusion DWI is a valuable technique enables the detection of changes in DWI after ESWL treatment that may provide useful information in prediction of renal damage by shock waves, even CDUS is normal. PMID:25928520

  3. Histological grade of differentiation of hepatocellular carcinoma: comparison of the efficacy of diffusion-weighted MRI with T2-weighted imaging and angiography-assisted CT

    International Nuclear Information System (INIS)

    Saito, Kazuhiro; Nishio, Ryota; Saguchi, Toru; Akata, Soichi; Tokuuye, Koichi; Moriyasu, Fuminori; Sugimoto, Katsutoshi

    2012-01-01

    The purpose of this study is to determine the usefulness of diffusion-weighted imaging (DWI) for evaluating the histological grade of differentiation of hepatocellular carcinoma (HCC) compared with T2-weighted imaging (T2WI) and tumour haemodynamics. We retrospectively evaluated 32 patients with 42 pathologically confirmed HCC nodules. These patients underwent MRI, CT during arterial portography and CT hepatic arteriography. We evaluated the relationship between the histological grade of differentiation and the apparent diffusion coefficient (ADC) values, conspicuity of tumour on DWI, DWI and T2WI contrast-to-noise (C/N) ratios and tumour haemodynamics. There was no correlation between the histological grade of differentiation and the ADC values. The DWI C/N ratio was significantly different among all histological grades, but the T2WI C/N ratio was not. Tumour conspicuity on DWI correlated well with the histological grade of differentiation, but tumour haemodynamics only partially correlated with the histological grade of differentiation. DWI was useful for evaluating the histological grade of differentiation of HCC.

  4. Pre-treatment functional MRI of breast cancer: T2* evaluation at 3 T and relationship to dynamic contrast-enhanced and diffusion-weighted imaging.

    Science.gov (United States)

    Kousi, Evanthia; O'Flynn, Elizabeth A M; Borri, Marco; Morgan, Veronica A; deSouza, Nandita M; Schmidt, Maria A

    2018-05-31

    Baseline T2* relaxation time has been proposed as an imaging biomarker in cancer, in addition to Dynamic Contrast-Enhanced (DCE) MRI and diffusion-weighted imaging (DWI) parameters. The purpose of the current work is to investigate sources of error in T2* measurements and the relationship between T2* and DCE and DWI functional parameters in breast cancer. Five female volunteers and thirty-two women with biopsy proven breast cancer were scanned at 3 T, with Research Ethics Committee approval. T2* values of the normal breast were acquired from high-resolution, low-resolution and fat-suppressed gradient-echo sequences in volunteers, and compared. In breast cancer patients, pre-treatment T2*, DCE MRI and DWI were performed at baseline. Pathologically complete responders at surgery and non-responders were identified and compared. Principal component analysis (PCA) and cluster analysis (CA) were performed. There were no significant differences between T2* values from high-resolution, low-resolution and fat-suppressed datasets (p > 0.05). There were not significant differences between baseline functional parameters in responders and non-responders (p > 0.05). However, there were differences in the relationship between T2* and contrast-agent uptake in responders and non-responders. Voxels of similar characteristics were grouped in 5 clusters, and large intra-tumoural variations of all parameters were demonstrated. Breast T2* measurements at 3 T are robust, but spatial resolution should be carefully considered. T2* of breast tumours at baseline is unrelated to DCE and DWI parameters and contribute towards describing functional heterogeneity of breast tumours. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Prostate cancer: diagnostic value of dynamic contrast-enhanced MRI, diffusion weighted imaging and 3D 1H-MR spectroscopy

    International Nuclear Information System (INIS)

    Shi Hao; Wu Lebin; Ding Hongyu; Zhao Bin; Wang Tao; Yang Zhenzhen; Qiu Xiuling; Li Huihua; Qu Lei; Wu Yulong

    2006-01-01

    Objective: To explore the applying value of the diagnosis of dynamic contrast-enhanced MRI (DCE-MRI), diffusion weighted imaging (DWI) and 3D 1 H-MR spectroscopy (MRS) in prostate cancer (PC). Methods: Thirty-two cases with PC and 64 cases with benign prostatic hyperplasia (BPH) which were confirmed with biopsy-proven, operation and follow-up, and 29 healthy volunteers underwent the examinations of DCE-MRI, DWI and MRS. The signal intensity, ADC value, and Cho/Cit ratio and (Cho + Cr)/Cit ratio were measured respectively on the lesions of PC and BPH, normal prostatic peripheral zone (PZ) and normal prostatic central gland (CG) of DCE-MRI, DWI and MRS. The results were statistically treated with ANOVA. Results: The lesions showed obvious enhancement in the early phase of DCE-MRI and washed out in late phase in 18 of 22 cases with PC, who underwent the examination of DCE-MRI. The enhancement was obvious in early and strengthened gradually, and then went to decrease in late phase after peak value on the lesions in 38 of 40 cases with BPH. The signal intensities from different time and different lesions and tissues were treated statistically and the results showed that there were significant differences (P 0.05). The lesions were shown lower signal intensity on ADC map in 26 cases with PC, who were examined with DWI and the average ADC value was (104.23±26.15) x 10 -5 mm 2 /s. The average ADC Value of the lesions of 43 cases with BPH was (175.21±64.86) x 10 -5 mm 2 /s. The statistical analysis showed that there were significant differences between PC, BPH and CG except between PZ and BPH. Average Cho/Cit ratio and average (Cho + Cr)/Cit ratio of the lesions of PC were 2.26±0.91 and 2.85±1.01 respectively in 17 cases with PC, who were performed with MRS. The average Cho/Cit ratio and average (Cho + Cr)/Cit ratio were 0.46±0.23 and 0.57±0.20 respectively in 35 cases with BPH. After the statistical analyzing, the results presented that there were significant

  6. Comparison of diffusion-weighted whole body MRI and skeletal scintigraphy for the detection of bone metastases in patients with prostate or breast carcinoma

    International Nuclear Information System (INIS)

    Gutzeit, Andreas; Doert, Aleksis; Froehlich, Johannes M.; Eckhardt, Boris P.; Meili, Andreas; Scherr, Patrick; Schmid, Daniel T.; Weymarn, Constantin A. von; Willemse, Edwin M.M.; Binkert, Christoph A.; Graf, Nicole

    2010-01-01

    To prospectively compare the diagnostic accuracy of diffusion-weighted whole body imaging with background whole body signal suppression (DWIBS) with skeletal scintigraphy for the diagnosis and differentiation of skeletal lesions in patients suffering from prostate or breast cancer. A diagnostic cohort of 36 patients was included in skeletal scintigraphy and 1.5 T DWIBS MRI. Based on morphology and signal intensity patterns, two readers each identified and classified independently, under blinded conditions, all lesions into three groups: (1) malignant, (2) unclear if malignant or benign and (3) benign. Finally, for the definition of the gold standard all available imaging techniques and follow-up over a minimum of 6 months were considered. Overall, 45 circumscribed bone metastases and 107 benign lesions were found. DWIBS performed significantly better in detecting malignant skeletal lesions in patients with more than 10 lesions (sensitivity: 0.97/0.91) compared to skeletal scintigraphy (sensitivity: 0.48/0.42). No statistical difference could be found between DWIBS (0.58/0.33) and skeletal scintigraphy (0.67/0.58) in the sensitivity values for malignant skeletal lesions in patients with less than 5 lesions. For benign lesions, scintigraphy scored best with a sensitivity of 0.93/0.87 compared to 0.20/0.13 for DWIBS. Interobserver agreement with Cohen's kappa coefficient was calculated as 0.784 in the case of scintigraphy and 0.663 for DWIBS. With respect to staging, in prostate and breast carcinoma, the DWIBS technique is not superior to skeletal scintigraphy, but ranks equally. However, in the cases with many bone lesions, markedly more metastases could be discovered using the DWIBS technique than skeletal scintigraphy. (orig.)

  7. 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.)

  8. MRI and Diffusion-weighted MRI Volumetry for Identification of Complete Tumor Responders After Preoperative Chemoradiotherapy in Patients With Rectal Cancer: A Bi-institutional Validation Study.

    Science.gov (United States)

    Lambregts, Doenja M J; Rao, Sheng-Xiang; Sassen, Sander; Martens, Milou H; Heijnen, Luc A; Buijsen, Jeroen; Sosef, Meindert; Beets, Geerard L; Vliegen, Roy A; Beets-Tan, Regina G H

    2015-12-01

    Retrospective single-center studies have shown that diffusion-weighted magnetic resonance imaging (DWI) is promising for identification of patients with rectal cancer with a complete tumor response after neoadjuvant chemoradiotherapy (CRT), using certain volumetric thresholds. This study aims to validate the diagnostic value of these volume thresholds in a larger, independent, and bi-institutional patient cohort. A total of 112 patients with locally advanced rectal cancer (2 centers) treated with a long course of CRT were enrolled. Patients underwent standard T2W-magnetic resonance imaging and DWI, both pre- and post-CRT. Two experienced readers independently determined pre-CRT and post-CRT tumor volumes (cm) on T2W-magnetic resonance image and diffusion-weighted magnetic resonance image by means of freehand tumor delineation. Tumor volume reduction rates (Δvolume) were calculated. Previously determined T2W and DWI threshold values for prevolume, postvolume, and Δvolume were tested to "prospectively" assess their respective diagnostic value in discriminating patients with a complete tumor response from patients with residual tumor. Twenty patients had a complete response. Using the average measurements between the 2 readers, areas under the curve for the pre-/post-/Δvolumes was 0.73/0.82/0.78 for T2W-magnetic resonance imaging and 0.77/0.92/0.86 for DWI, respectively. For T2W-volumetry, sensitivity and specificity using the predefined volume thresholds were 55% and 74% for pre-, 60% and 89% for post-, and 60% and 86% for Δvolume. For DWI volumetry, sensitivity and specificity were 65% and 76% for pre-, 70% and 98% for post-, and 70% and 93% for Δvolume. Previously established DWI volume thresholds can be reproduced with good results. Post-CRT DWI volumetry offers the best results for the detection of patients with a complete response after CRT with an area under the curve of 0.92, sensitivity of 70%, and specificity of 98%.

  9. Non-invasive estimation of prostate cancer aggressiveness using diffusion-weighted MRI and 3D proton MR spectroscopy at 3.0 T.

    Science.gov (United States)

    Thörmer, Gregor; Otto, Josephin; Horn, Lars-Christian; Garnov, Nikita; Do, Minh; Franz, Toni; Stolzenburg, Jens-Uwe; Moche, Michael; Kahn, Thomas; Busse, Harald

    2015-01-01

    Clinical management of prostate cancer increasingly aims to distinguish aggressive types that require immediate and radical treatment from indolent tumors that are candidates for watchful waiting. This requires reliable and reproducible parameters to effectively control potential cancer progression. Magnetic resonance imaging (MRI) may provide a non-invasive means for this purpose. To assess the value of diffusion-weighted imaging and proton MR spectroscopy for the prediction of prostate cancer (PCa) aggressiveness. In 39 of 64 consecutive patients who underwent endorectal 3-T MRI prior to radical prostatectomy, prostate specimens were analyzed as whole-mount step sections. Apparent diffusion coefficient (ADC), normalized ADC (nADC: tumor/healthy tissue), choline/citrate (CC), and (choline + creatine)/citrate (CCC) ratios were correlated with Gleason scores (GS) from histopathological results. The power to discriminate low (GS ≤ 6) from higher-risk (GS ≥ 7) tumors was assessed with receiver operating characteristics (area under the curve [AUC]). Resulting threshold values were used by a blinded reader to distinguish between aggressive and indolent tumors. Ninety lesions (1 × GS = 5, 41 × GS = 6, 36 × GS = 7, 12 × GS = 8) were considered. nADC (AUC = 0.90) showed a higher discriminatory power than ADC (AUC = 0.79). AUC for CC and CCC were 0.73 and 0.82, respectively. Using either nADC  1.3, as well as both criteria for aggressive PCa, the reader correctly identified aggressive and indolent tumors in 31 (79%), 28 (72%), and 33 of 39 patients (85%), respectively. Predictions of tumor aggressiveness from TRUS-guided biopsies were correct in 27 of 36 patients (75%). The combination of a highly sensitive normalized ADC with a highly specific CCC was found to be well suited to prospectively estimate PCa aggressiveness with a similar diagnostic accuracy as biopsy results. © The Foundation Acta Radiologica

  10. [Diffusion weighted imaging and perfusion weighted imaging in the differential diagnosis of benign and malignant renal masses on 3.0 T MRI].

    Science.gov (United States)

    Xu, Xiaowen; Wang, Peijun; Ma, Liang; Shao, Zhihong; Zhang, Min

    2015-01-20

    To explore the value of diffusion weighted imaging (DWI) and perfusion weighted imaging (PWI) in identifying benign and malignant renal masses and differentiating the histological types of renal masses. Fifteen healthy volunteers and 46 patients with renal masses proven by pathology, including clear cell carcinomas (n = 18), papillary carcinomas (n = 8), chromophobe carcinomas (n = 7) and angiomyolipomas (n = 13), were examined with DWI and PWI scan at 3.0 T MRI. ANOVA was employed to compare the values of transfer constant (K(trans)), rate constant of backflux (Kep) and extra-vascular extra-cellular space fractional volume (Ve) proceeded by PWI and the value of ADC resulted from DWI between normal kidney and different histological types of renal masses. Receiver operating characteristics (ROC) curve was used to analyze and compare the diagnostic value of the methods of PWI and DWI in differentiating benign and malignant renal masses. The ADC value of normal renal parenchyma was (2.10 ± 0.24) × 10⁻³ mm²/s, which was statistically higher than benign and malignant renal masses (P 0.05).Values of K(trans), Kep and Ve between normal renal parenchyma and different histological types of renal masses had statistical differences.Values of K(trans) and Ve in three histological types of malignant renal masses were statistically higher than those of benign renal masses.Kep value of clear cell carcinoma was significantly higher than that of benign renal masses (P benign and malignant renal masses. The K(trans) of benign and malignant renal masses had the largest AUC (AUC = 0.937) at a threshold of 0.38/min. And there were a sensitivity of 87.9% and a specificity of 85.7%. The AUC of ADC was 0.823, sensitivity 72.7% and specificity 92.9%. The ADC threshold for differentiating benign from malignant masses was 1.40 × 10⁻³ mm²/s; AUC of Ve 0.803, sensitivity 78.8% and specificity 71.4%, a threshold of 0.29/min; Kep showed lower diagnostic value. 3.0 T MRI DWI and PWI

  11. Serial MRI studies using gadolinium DTPA in active multiple sclerosis

    International Nuclear Information System (INIS)

    Miller, D.H.; Johnson, G.; Barnes, D.; Rudge, P.; McDonald, W.I.

    1988-01-01

    It has been suggested that blood brain barrier (BBB) impairment is a necessary early event in the pathogenesis of the multiple sclerosis (MS) lesions. To evaluate such an hypothesis in vivo would require: (1) serial imaging studies using a modality with high sensitivity for detecting plaques; (2) a contrast enhancing agent which demonstrates BBB impairment. A serial magnetic resonance imaging (MRI) study was undertaken of a group of MS patients using the contrast agent gadolinium-DTPA. As it has been suggested that T 1 and T 2 relaxation times are longer in acute than chronic MS lesions, these were also measured. 3 refs.; 1 figure

  12. TU-F-CAMPUS-J-02: Evaluation of Textural Feature Extraction for Radiotherapy Response Assessment of Early Stage Breast Cancer Patients Using Diffusion Weighted MRI and Dynamic Contrast Enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Y; Wang, C; Horton, J; Chang, Z [Duke University Medical Center, Durham, NC (United States)

    2015-06-15

    Purpose: To investigate the feasibility of using classic textural feature extraction in radiotherapy response assessment, we studied a unique cohort of early stage breast cancer patients with paired pre - and post-radiation Diffusion Weighted MRI (DWI-MRI) and Dynamic Contrast Enhanced MRI (DCE-MRI). Methods: 15 female patients from our prospective phase I trial evaluating preoperative radiotherapy were included in this retrospective study. Each patient received a single-fraction radiation treatment, and DWI and DCE scans were conducted before and after the radiotherapy. DWI scans were acquired using a spin-echo EPI sequence with diffusion weighting factors of b = 0 and b = 500 mm{sup 2} /s, and the apparent diffusion coefficient (ADC) maps were calculated. DCE-MRI scans were acquired using a T{sub 1}-weighted 3D SPGR sequence with a temporal resolution of about 1 minute. The contrast agent (CA) was intravenously injected with a 0.1 mmol/kg bodyweight dose at 2 ml/s. Two parameters, volume transfer constant (K{sup trans} ) and k{sub ep} were analyzed using the two-compartment Tofts kinetic model. For DCE parametric maps and ADC maps, 33 textural features were generated from the clinical target volume (CTV) in a 3D fashion using the classic gray level co-occurrence matrix (GLCOM) and gray level run length matrix (GLRLM). Wilcoxon signed-rank test was used to determine the significance of each texture feature’s change after the radiotherapy. The significance was set to 0.05 with Bonferroni correction. Results: For ADC maps calculated from DWI-MRI, 24 out of 33 CTV features changed significantly after the radiotherapy. For DCE-MRI pharmacokinetic parameters, all 33 CTV features of K{sup trans} and 33 features of k{sub ep} changed significantly. Conclusion: Initial results indicate that those significantly changed classic texture features are sensitive to radiation-induced changes and can be used for assessment of radiotherapy response in breast cancer.

  13. Multimodality Functional Imaging in Radiation Therapy Planning: Relationships between Dynamic Contrast-Enhanced MRI, Diffusion-Weighted MRI, and 18F-FDG PET

    Directory of Open Access Journals (Sweden)

    Moisés Mera Iglesias

    2015-01-01

    Full Text Available Objectives. Biologically guided radiotherapy needs an understanding of how different functional imaging techniques interact and link together. We analyse three functional imaging techniques that can be useful tools for achieving this objective. Materials and Methods. The three different imaging modalities from one selected patient are ADC maps, DCE-MRI, and 18F-FDG PET/CT, because they are widely used and give a great amount of complementary information. We show the relationship between these three datasets and evaluate them as markers for tumour response or hypoxia marker. Thus, vascularization measured using DCE-MRI parameters can determine tumour hypoxia, and ADC maps can be used for evaluating tumour response. Results. ADC and DCE-MRI include information from 18F-FDG, as glucose metabolism is associated with hypoxia and tumour cell density, although 18F-FDG includes more information about the malignancy of the tumour. The main disadvantage of ADC maps is the distortion, and we used only low distorted regions, and extracellular volume calculated from DCE-MRI can be considered equivalent to ADC in well-vascularized areas. Conclusion. A dataset for achieving the biologically guided radiotherapy must include a tumour density study and a hypoxia marker. This information can be achieved using only MRI data or only PET/CT studies or mixing both datasets.

  14. 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

  15. Diffusion-weighted MRI of the prostate at 3.0 T: Comparison of endorectal coil (ERC) MRI and phased-array coil (PAC) MRI—The impact of SNR on ADC measurement

    International Nuclear Information System (INIS)

    Mazaheri, Yousef; Vargas, H. Alberto; Nyman, Gregory; Shukla-Dave, Amita; Akin, Oguz; Hricak, Hedvig

    2013-01-01

    Purpose: To compare ADC values measured from diffusion-weighted MR (DW-MR) images of the prostate obtained with both endorectal and phased-array coils (ERC + PAC) to those from DW-MRI images obtained with an eight-channel torso phased-array coil (PAC) at 3.0 T. Methods: The institutional review board issued a waiver of informed consent for this HIPAA-compliant study. Twenty-five patients with biopsy-proven prostate cancer underwent standard 3-T MRI using 2 different coil arrangements (ERC + PAC and PAC only) in the same session. DW-MRI at five b-values (0, 600, 1000, 1200, and 1500 s/mm 2 ) were acquired using both coil arrangements. On b = 0 images, signal-to-noise ratios (SNRs) were measured as the ratio of the mean signal from PZ and TZ ROIs to the standard deviation from the mean signal in an artifact-free ROI in the rectum. Matching regions-of-interest (ROIs) were identified in the peripheral zone and transition zone on ERC-MRI and PAC-MRI. For each ROI, mean ADC values for all zero and non-zero b-value combinations were computed. Results: Mean SNR with ERC-MRI at PZ (66.33 ± 27.07) and TZ (32.69 ± 12.52) was 9.27 and 5.52 times higher than with PAC-MRI ((7.32 ± 2.30) and (6.13 ± 1.56), respectively) (P < 0.0001 for both). ADCs from DW-MR images obtained with all b-values in the PZ and TZ were significantly lower with PAC-MRI than with ERC-MRI (P < 0.001 for all). Conclusion: Lower SNR of DW-MR images of the prostate obtained with a PAC can significantly decrease ADC values at higher b-values compared to similar measurements obtained using the ERC. To address these requirements, clinical MR systems should have image processing capabilities which incorporate the noise distribution

  16. SU-F-303-13: Initial Evaluation of Four Dimensional Diffusion- Weighted MRI (4D-DWI) and Its Effect On Apparent Diffusion Coefficient (ADC) Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y [Duke University Medical Physics Program (United States); Yin, F; Czito, B; Bashir, M; Palta, M; Cai, J [Duke University Medical Center, Durham, NC (United States); Zhong, X; Dale, B [Siemens Healthcare, Durham, NC (United States)

    2015-06-15

    Purpose: Diffusion-weighted imaging(DWI) has been shown to have superior tumor-to-tissue contrast for cancer detection.This study aims at developing and evaluating a four dimensional DWI(4D-DWI) technique using retrospective sorting method for imaging respiratory motion for radiotherapy planning,and evaluate its effect on Apparent Diffusion Coefficient(ADC) measurement. Materials/Methods: Image acquisition was performed by repeatedly imaging a volume of interest using a multi-slice single-shot 2D-DWI sequence in the axial planes and cine MRI(served as reference) using FIESTA sequence.Each 2D-DWI image were acquired in xyz-diffusion-directions with a high b-value(b=500s/mm2).The respiratory motion was simultaneously recorded using bellows.Retrospective sorting was applied in each direction to reconstruct 4D-DWI.The technique was evaluated using a computer simulated 4D-digital human phantom(XCAT),a motion phantom and a healthy volunteer under an IRB-approved study.Motion trajectories of regions-of-interests(ROI) were extracted from 4D-DWI and compared with reference.The mean motion trajectory amplitude differences(D) between the two was calculated.To quantitatively analyze the motion artifacts,XCAT were controlled to simulate regular motion and the motions of 10 liver cancer patients.4D-DWI,free-breathing DWI(FB- DWI) were reconstructed.Tumor volume difference(VD) of each phase of 4D-DWI and FB-DWI from the input static tumor were calculated.Furthermore, ADC was measured for each phase of 4D-DWI and FB-DWI data,and mean tumor ADC values(M-ADC) were calculated.Mean M-ADC over all 4D-DWI phases was compared with M-ADC calculated from FB-DWI. Results: 4D-DWI of XCAT,the motion phantom and the healthy volunteer demonstrated the respiratory motion clearly.ROI D values were 1.9mm,1.7mm and 2.0mm,respectively.For motion artifacts analysis,XCAT 4D-DWI images show much less motion artifacts compare to FB-DWI.Mean VD for 4D-WDI and FB-DWI were 8.5±1.4% and 108±15

  17. Automated detection of multiple sclerosis lesions in serial brain MRI

    International Nuclear Information System (INIS)

    Llado, Xavier; Ganiler, Onur; Oliver, Arnau; Marti, Robert; Freixenet, Jordi; Valls, Laia; Vilanova, Joan C.; Ramio-Torrenta, Lluis; Rovira, Alex

    2012-01-01

    Multiple sclerosis (MS) is a serious disease typically occurring in the brain whose diagnosis and efficacy of treatment monitoring are vital. Magnetic resonance imaging (MRI) is frequently used in serial brain imaging due to the rich and detailed information provided. Time-series analysis of images is widely used for MS diagnosis and patient follow-up. However, conventional manual methods are time-consuming, subjective, and error-prone. Thus, the development of automated techniques for the detection and quantification of MS lesions is a major challenge. This paper presents an up-to-date review of the approaches which deal with the time-series analysis of brain MRI for detecting active MS lesions and quantifying lesion load change. We provide a comprehensive reference source for researchers in which several approaches to change detection and quantification of MS lesions are investigated and classified. We also analyze the results provided by the approaches, discuss open problems, and point out possible future trends. Lesion detection approaches are required for the detection of static lesions and for diagnostic purposes, while either quantification of detected lesions or change detection algorithms are needed to follow up MS patients. However, there is not yet a single approach that can emerge as a standard for the clinical practice, automatically providing an accurate MS lesion evolution quantification. Future trends will focus on combining the lesion detection in single studies with the analysis of the change detection in serial MRI. (orig.)

  18. Automated detection of multiple sclerosis lesions in serial brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Llado, Xavier; Ganiler, Onur; Oliver, Arnau; Marti, Robert; Freixenet, Jordi [University of Girona, Computer Vision and Robotics Group, Girona (Spain); Valls, Laia [Dr. Josep Trueta University Hospital, Department of Radiology, Girona (Spain); Vilanova, Joan C. [Girona Magnetic Resonance Center, Girona (Spain); Ramio-Torrenta, Lluis [Dr. Josep Trueta University Hospital, Institut d' Investigacio Biomedica de Girona, Multiple Sclerosis and Neuroimmunology Unit, Girona (Spain); Rovira, Alex [Vall d' Hebron University Hospital, Magnetic Resonance Unit, Department of Radiology, Barcelona (Spain)

    2012-08-15

    Multiple sclerosis (MS) is a serious disease typically occurring in the brain whose diagnosis and efficacy of treatment monitoring are vital. Magnetic resonance imaging (MRI) is frequently used in serial brain imaging due to the rich and detailed information provided. Time-series analysis of images is widely used for MS diagnosis and patient follow-up. However, conventional manual methods are time-consuming, subjective, and error-prone. Thus, the development of automated techniques for the detection and quantification of MS lesions is a major challenge. This paper presents an up-to-date review of the approaches which deal with the time-series analysis of brain MRI for detecting active MS lesions and quantifying lesion load change. We provide a comprehensive reference source for researchers in which several approaches to change detection and quantification of MS lesions are investigated and classified. We also analyze the results provided by the approaches, discuss open problems, and point out possible future trends. Lesion detection approaches are required for the detection of static lesions and for diagnostic purposes, while either quantification of detected lesions or change detection algorithms are needed to follow up MS patients. However, there is not yet a single approach that can emerge as a standard for the clinical practice, automatically providing an accurate MS lesion evolution quantification. Future trends will focus on combining the lesion detection in single studies with the analysis of the change detection in serial MRI. (orig.)

  19. 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

  20. Functional imaging of submandibular glands: diffusion-weighted echo-planar MRI before and after stimulation; Diffusionsgewichtete MRT zur Funktionsdiagnostik der Glandula submandibularis

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, C.; Cramer, M.C.; Weiss, F.; Kaul, M.G.; Adam, G.; Habermann, C.R. [Zentrum fuer Bildgebende Diagnostik und Intervention, Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Graessner, J. [Siemens Medical Solutions (Germany); Petersen, K. [Zentrum fuer Psychosoziale Medizin, Klinik und Poliklinik fuer Psychiatrie und Psychotherapie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Reitmeier, F.; Jaehne, M. [Kopf und Hautzentrum, Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenheilkunde, Universitaetsklinikum Hamburg Eppendorf (Germany)

    2006-09-15

    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{sup 2}, 500 sec/mm{sup 2} and 1000 sec/mm{sup 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{sup -3

  1. Dynamic contrast-enhanced MRI, diffusion-weighted MRI and {sup 18}F-FDG PET/CT for the prediction of survival in oropharyngeal or hypopharyngeal squamous cell carcinoma treated with chemoradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Shu-Hang [Chang Gung University, Molecular Imaging Center, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Chang Gung University, Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Chang Gung University, Department of Medical Imaging and Radiological Sciences, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Liao, Chun-Ta [Chang Gung University, Department of Otorhinolaryngology, Head and Neck Surgery, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Lin, Chien-Yu; Chang, Joseph Tung-Chieh; Fan, Kang-Hsing [Chang Gung University, Department of Radiation Oncology, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Chan, Sheng-Chieh; Yen, Tzu-Chen [Chang Gung University, Molecular Imaging Center, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Chang Gung University, Department of Nuclear Medicine, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Lin, Yu-Chun [Chang Gung University, Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Chang Gung University, Department of Medical Imaging and Radiological Sciences, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Ko, Sheung-Fat [Chang Gung University, Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Wang, Hung-Ming [Chang Gung University, Department of Medical Oncology, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Yang, Lan-Yan [Chang Gung University, Biostatistics and Informatics Unit, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Wang, Jiun-Jie [Chang Gung University, Department of Medical Imaging and Radiological Sciences, Chang Gung Memorial Hospital, Kueishan, Taoyuan (China); Chang Gung Memorial Hospital, Neuroscience Research Center, Taoyuan (China); Chang Gung Memorial Hospital, Department of Diagnostic Radiology, Keelung (China); Chang Gung University / Chang Gung Memorial Hospital, Linkou, Medical Imaging Research Center, Institute for Radiological Research, Taoyuan (China)

    2016-11-15

    We prospectively investigated the roles of pretreatment dynamic contrast-enhanced MR imaging (DCE-MRI), diffusion-weighted MR imaging (DWI) and {sup 18}F-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG PET)/CT for predicting survival of oropharyngeal or hypopharyngeal squamous cell carcinoma (OHSCC) patients treated with chemoradiation. Patients with histologically proven OHSCC and neck nodal metastases scheduled for chemoradiation were eligible. Clinical variables as well as DCE-MRI-, DWI- and {sup 18}F-FDG PET/CT-derived parameters of the primary tumours and metastatic neck nodes were analysed in relation to 3-year progression-free survival (PFS) and overall survival (OS) rates. Eighty-six patients were available for analysis. Multivariate analysis identified the efflux rate constant (K{sub ep})-tumour < 3.79 min{sup -1} (P = 0.001), relative volume of extracellular extravascular space (V{sub e})-node < 0.23 (P = 0.004) and SUV{sub max}-tumour > 19.44 (P = 0.025) as independent risk factors for both PFS and OS. A scoring system based upon the sum of each of the three imaging parameters allowed stratification of our patients into three groups (patients with 0/1 factor, patients with 2 factors and patients with 3 factors, respectively) with distinct PFS (3-year rates = 72 %, 38 % and 0 %, P < 0.0001) and OS (3-year rates = 81 %, 46 % and 20 %, P < 0.0001). K{sub ep}-tumour, V{sub e}-node and SUV{sub max}-tumour were independent prognosticators for OHSCC treated with chemoradiation. Their combination helped survival stratification. (orig.)

  2. Cortical laminar necrosis in brain infarcts: serial MRI

    Energy Technology Data Exchange (ETDEWEB)

    Siskas, N.; Lefkopoulos, A.; Ioannidis, I.; Charitandi, A.; Dimitriadis, A.S. [Radiology Department, AHEPA University Hospital, Aristotele University of Thessaloniki (Greece)

    2003-05-01

    High-signal cortical lesions are observed on T1-weighted images in cases of brain infarct. Histological examination has demonstrated these to be ''cortical laminar necrosis'', without haemorrhage or calcification. We report serial MRI in this condition in 12 patients with brain infarcts. We looked at high-signal lesions on T1-weighted images, chronological changes in signal intensity and contrast enhancement. High-signal cortical lesions began to appear about 2 weeks after the ictus, were prominent at 1 - 2 months, then became less evident, but occasionally remained for up to 1.5 years. They gave high signal or were isointense on T2-weighted images and did not give low signal at any stage. Contrast enhancement of these lesions was prominent at 1 - 2 months, and less apparent from 3 months, but was seen up to 5 months. (orig.)

  3. Diffusion-Weighted MRI in the Assessment of Early Treatment Response in Patients with Squamous-Cell Carcinoma of the Head and Neck: Comparison with Morphological and PET/CT Findings.

    Directory of Open Access Journals (Sweden)

    Eduardo Bruno Lobato Martins

    Full Text Available To evaluate changes in apparent diffusion coefficients (ADC as measured by magnetic resonance imaging (MRI before and after the treatment of primary tumors and cervical metastases in patients with squamous-cell carcinoma (SCC of the head and neck, and to compare these values to the results of widely used morphological criteria and [18F]-FDG PET/CT findings.This was a longitudinal, prospective, single-center nonrandomized trial involving patients with head and neck SCC treated with chemotherapy alone or in combination with radiotherapy. Imaging examinations ([18F]-FDG PET/CT and diffusion-weighted MRI were performed on the same day, up to one day prior to the beginning of the first treatment cycle, and on the 14th day of the first chemotherapy cycle. Treatment response was evaluated based on the Response Evaluation Criteria in Solid Tumors (RECIST and World Health Organization (WHO morphological criteria, as well as PET Response Criteria in Solid Tumors (PERCIST metabolic criteria.Seventy-five lesions were examined in 23 patients. Pre- and post-treatment comparisons of data pertaining to all target lesions revealed reductions in tumor size and SUV, as well as increases in ADC values, all of which were statistically significant. The increase in ADC following treatment was significantly higher in patients classified as complete responders by both morphological criteria than that observed in any of the other patient groups of response. Patients with a complete metabolic response also showed greater increases in ADC values as compared to the remaining groups.The assessment of tumor response based on diffusion-weighted MRI showed an increase in the ADC of cervical lesions following treatment, which was corroborated by morphological and metabolic findings. Associations between changes in ADC values and treatment response categories using morphologic criteria and [18F]-FDG PET/CT were only identified in complete responders.

  4. Selected clinically established and scientific techniques of diffusion-weighted MRI. In the context of imaging in oncology; Ausgewaehlte klinisch etablierte und wissenschaftliche Techniken der diffusionsgewichteten MRT. Im Kontext der onkologischen Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, M.T.; Bickelhaupt, S.; Ziener, C.; Mosebach, J.; Schlemmer, H.P. [Deutsches Krebsforschungszentrum, Abteilung fuer Radiologie, Heidelberg (Germany); Meier-Hein, K. [Deutsches Krebsforschungszentrum, Abteilung fuer medizinische Informatik, Heidelberg (Germany); Radtke, J.P. [Deutsches Krebsforschungszentrum, Abteilung fuer Radiologie, Heidelberg (Germany); Universitaetsklinik Heidelberg, Abteilung fuer Urologie, Heidelberg (Germany); Kuder, T.A.; Laun, F.B. [Deutsches Krebsforschungszentrum, Abteilung fuer Medizinische Physik in der Radiologie, Heidelberg (Germany)

    2016-02-15

    Diffusion-weighted imaging (DWI) is a magnetic resonance imaging (MRI) technique that was established in the clinical routine primarily for the detection of brain ischemia. In the past 15 years its clinical use has been extended to oncological radiology, as tumor and metastases can be depicted in DWI due to their hypercellular nature. The basis of DWI is the Stejskal-Tanner experiment. The diffusion properties of tissue can be visualized after acquisition of at least two diffusion-weighted series using echo planar imaging and a specific sequence of gradient pulses. The use of DWI in prostate MRI was reported to be one of the first established applications that found its way into internationally recognized clinical guidelines of the European Society of Urological Radiology (ESUR) and the prostate imaging reporting and data system (PI-RADS) scale. Due to recently reported high specificity and negative predictive values of 94 % and 92 %, respectively, its regular use for breast MRI is expected in the near future. Furthermore, DWI can also reliably be used for whole-body imaging in patients with multiple myeloma or for measuring the extent of bone metastases. New techniques in DWI, such as intravoxel incoherent motion imaging, diffusion kurtosis imaging and histogram-based analyses represent promising approaches to achieve a more quantitative evaluation for tumor detection and therapy response. (orig.) [German] Die diffusionsgewichtete Bildgebung (''diffusion-weighted imaging'', DWI), ein Verfahren aus der Magnetresonanztomographie (MRT), wurde in der klinischen Routine primaer fuer die Detektion von Schlaganfaellen etabliert. Der Einsatz dieser Methode hat in den letzten 15 Jahren auch fuer die onkologische Diagnostik stark zugenommen, da Tumoren und Metastasen aufgrund ihrer hochzellulaeren Zusammensetzung in der DWI sehr gut sichtbar gemacht werden koennen. Basis der diffusionsgewichteten Bildgebung ist das Experiment nach Stejskal-Tanner. Hier

  5. Improved differentiation between hepatic hemangioma and metastases on diffusion-weighted MRI by measurement of standard deviation of apparent diffusion coefficient.

    Science.gov (United States)

    Hardie, Andrew D; Egbert, Robert E; Rissing, Michael S

    2015-01-01

    Diffusion-weighted magnetic resonance imaging (DW-MR) can be useful in the differentiation of hemangiomata from liver metastasis, but improved methods other than by mean apparent diffusion coefficient (mADC) are needed. A retrospective review identified 109 metastatic liver lesions and 86 hemangiomata in 128 patients who had undergone DW-MR. For each lesion, mADC and the standard deviation of the mean ADC (sdADC) were recorded and compared by receiver operating characteristic analysis. Mean mADC was higher in benign hemangiomata (1.52±0.12 mm(2)/s) than in liver metastases (1.33±0.18 mm(2)/s), but there was significant overlap in values. The mean sdADC was lower in hemangiomata (101±17 mm(2)/s) than metastases (245±25 mm(2)/s) and demonstrated no overlap in values, which was significantly different (P<.0001). Hemangiomata may be better able to be differentiated from liver metastases on the basis of sdADC than by mADC, although further studies are needed. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Normal hepatic parenchyma visibility and ADC quantification on diffusion-weighted MRI at 3 T: influence of age, gender, and iron content

    Energy Technology Data Exchange (ETDEWEB)

    Metens, Thierry [MRI Clinics, Department of Radiology, Hopital Erasme, Bruxelles (Belgium); Universite Libre de Bruxelles, Magnetic Resonance Imaging Clinics, Department of Radiology, Hopital Erasme, Bruxelles (Belgium); Ferraresi, Kellen Fanstone; Farchione, Alessandra; Bali, Maria Antonietta; Matos, Celso [MRI Clinics, Department of Radiology, Hopital Erasme, Bruxelles (Belgium); Moreno, Christophe [Universite Libre de Bruxelles, Department of Gastroenterology, Hepatopancreatology, and Digestive Oncology, Hopital Erasme, Bruxelles (Belgium)

    2014-12-15

    To investigate how normal liver parenchyma visibility on 3 T diffusion-weighted images (DWI) and apparent diffusion coefficient (ADC) quantification are influenced by age, gender, and iron content. Between February 2011 and April 2013, 86 patients (52 women) with normal livers who underwent respiratory-triggered abdominal 3 T DWI (b = 0, 150, 600, 1,000 s/mm{sup 2}) were retrospectively included. Normal liver and spleen parenchyma visibility was scored independently by two readers. Correlations between visibility scores or ADC with age, gender, T2*, or recent serum ferritin (SF) were investigated. Liver visibility scores in b = 1,000 s/mm{sup 2} images correlated with the age (Spearman R = -0.56 in women, -0.45 in men), T2* (R = 0.75) and SF (R = -0.64) and were significantly higher in women (P < 0.01). SF and T2* were within normal values (T2*: 13 - 31 ms, SF: 14 - 230 μg/L). Liver ADC correlated with visibility scores (R = 0.69) and T2* (R = 0.64) and was age- and gender-dependent. ADC ROI standard deviation negatively correlated with visibility scores (R = -0.65) and T2* (R = -0.62). The spleen visibility did not depend on age or gender. Normal liver parenchyma visibility in DWI is age- and gender-dependent, according to the iron content. Visibility scores and iron content significantly affect ADC quantification in the normal liver. (orig.)

  7. Differential diagnosis of pituitary adenomas and Rathke's cleft cysts by diffusion-weighted MRI using single-shot fast spin echo technique

    International Nuclear Information System (INIS)

    Abe, Takumi; Izumiyama, Hitoshi; Fukuda, Ataru; Tanioka, Daisuke; Kunii, Norihiko; Komatsu, Daisuke; Fujita, Shogo; Ukisu, Ryutaro; Moritani, Toshio

    2002-01-01

    The purpose of the present study was to prospectively evaluate the diagnostic ability of diffusion-weighted magnetic resonance imaging (DWI) using single-shot fast spin echo (SSFSE) technique to discriminate pituitary adenomas from Rathke's cleft cysts. DWIs were obtained from 40 patients with pathologically proven pituitary macroadenomas and 15 patients with proven Rathke's cleft cysts. Pituitary adenomas were divided into 27 cases with solid components alone, five with non-hemorrhagic large cysts, and eight with intratumoral hemorrhage. On SSFSE DWI, solid components of pituitary adenomas revealed iso or slightly increased intensity and intratumoral hemorrhage showed higher intensity than normal brain parenchyma, whereas Rathke's cleft cysts and intratumoral cysts demonstrated very low intensity. SSFSE DWI did not display the susceptibility artifacts that are seen close to the skull base and sinonasal cavities on echo planar diffusion imaging. On the basis of our preliminary findings, DWI may enable us to differentiate pituitary adenomas with only solid components and hemorrhagic pituitary adenomas appearing hyperintense on T1-weighted images from Rathke's cleft cysts without administration of gadolinium-DTPA. SSFSE DWI appears to be a useful technique for characterizing pituitary diseases without the susceptibility artifacts. Our study is the first report to demonstrate the identification of pituitary disorders on SSFSE DWI. (author)

  8. Differential diagnosis of pituitary adenomas and Rathke's cleft cysts by diffusion-weighted MRI using single-shot fast spin echo technique

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Takumi; Izumiyama, Hitoshi; Fukuda, Ataru; Tanioka, Daisuke; Kunii, Norihiko; Komatsu, Daisuke; Fujita, Shogo; Ukisu, Ryutaro; Moritani, Toshio [Showa Univ., Tokyo (Japan). School of Medicine

    2002-09-01

    The purpose of the present study was to prospectively evaluate the diagnostic ability of diffusion-weighted magnetic resonance imaging (DWI) using single-shot fast spin echo (SSFSE) technique to discriminate pituitary adenomas from Rathke's cleft cysts. DWIs were obtained from 40 patients with pathologically proven pituitary macroadenomas and 15 patients with proven Rathke's cleft cysts. Pituitary adenomas were divided into 27 cases with solid components alone, five with non-hemorrhagic large cysts, and eight with intratumoral hemorrhage. On SSFSE DWI, solid components of pituitary adenomas revealed iso or slightly increased intensity and intratumoral hemorrhage showed higher intensity than normal brain parenchyma, whereas Rathke's cleft cysts and intratumoral cysts demonstrated very low intensity. SSFSE DWI did not display the susceptibility artifacts that are seen close to the skull base and sinonasal cavities on echo planar diffusion imaging. On the basis of our preliminary findings, DWI may enable us to differentiate pituitary adenomas with only solid components and hemorrhagic pituitary adenomas appearing hyperintense on T1-weighted images from Rathke's cleft cysts without administration of gadolinium-DTPA. SSFSE DWI appears to be a useful technique for characterizing pituitary diseases without the susceptibility artifacts. Our study is the first report to demonstrate the identification of pituitary disorders on SSFSE DWI. (author)

  9. Application of ADC measurement in characterization of renal cell carcinomas with different pathological types and grades by 3.0 T diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiaoduo, E-mail: yxd98@yahoo.com.cn [Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing (China); Lin, Meng, E-mail: linmeng77xp@yahoo.com.cn [Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing (China); Ouyang, Han, E-mail: hbybj@sohu.com [Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing (China); Zhou, Chunwu, E-mail: cjr.zhouchunwu@163.vip.com [Department of Diagnostic Radiology, Cancer Institute and Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing (China); Zhang, Hongtu, E-mail: zhanghongtu1010@yahoo.com.cn [Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing (China)

    2012-11-15

    Purpose: To test the feasibility of apparent diffusion coefficient (ADC) value obtained with 3.0 T diffusion-weighted imaging (DWI) in the characterization of renal cell carcinomas (RCC) with different pathological subtypes and grades. Materials and methods: A total of 137 patients who were diagnosed with RCC and underwent DWI were included in this study. The diagnosis was confirmed by pathological examination of surgical specimens. Images of DWI were obtained with b values of 0 and 800 s/mm{sup 2}. The ADC values in the solid area of tumors and in the corresponding regions of contralateral normal renal parenchyma were measured and analyzed statistically. Results: The mean ADC value was significantly lower in RCC (1.381 {+-} 0.444 Multiplication-Sign 10{sup -3} mm{sup 2}/s) than in normal renal parenchyma (2.232 {+-} 0.221 Multiplication-Sign 10{sup -3} mm{sup 2}/s) (P < 0.001). The ADC value was also statistically different between clear cell RCC (CCRCC) and non-CCRCC, and between different grades of CCRCC except grade I vs II and grade III vs IV. Conclusion: ADC measurement on 3.0 T DWI provides useful information in diagnostic work-up of RCC in terms of differentiation of RCC and normal renal parenchyma, and characterization of RCC with different pathological subtypes and grades.

  10. Normal hepatic parenchyma visibility and ADC quantification on diffusion-weighted MRI at 3 T: influence of age, gender, and iron content

    International Nuclear Information System (INIS)

    Metens, Thierry; Ferraresi, Kellen Fanstone; Farchione, Alessandra; Bali, Maria Antonietta; Matos, Celso; Moreno, Christophe

    2014-01-01

    To investigate how normal liver parenchyma visibility on 3 T diffusion-weighted images (DWI) and apparent diffusion coefficient (ADC) quantification are influenced by age, gender, and iron content. Between February 2011 and April 2013, 86 patients (52 women) with normal livers who underwent respiratory-triggered abdominal 3 T DWI (b = 0, 150, 600, 1,000 s/mm 2 ) were retrospectively included. Normal liver and spleen parenchyma visibility was scored independently by two readers. Correlations between visibility scores or ADC with age, gender, T2*, or recent serum ferritin (SF) were investigated. Liver visibility scores in b = 1,000 s/mm 2 images correlated with the age (Spearman R = -0.56 in women, -0.45 in men), T2* (R = 0.75) and SF (R = -0.64) and were significantly higher in women (P < 0.01). SF and T2* were within normal values (T2*: 13 - 31 ms, SF: 14 - 230 μg/L). Liver ADC correlated with visibility scores (R = 0.69) and T2* (R = 0.64) and was age- and gender-dependent. ADC ROI standard deviation negatively correlated with visibility scores (R = -0.65) and T2* (R = -0.62). The spleen visibility did not depend on age or gender. Normal liver parenchyma visibility in DWI is age- and gender-dependent, according to the iron content. Visibility scores and iron content significantly affect ADC quantification in the normal liver. (orig.)

  11. Prostate cancer: assessing the effects of androgen-deprivation therapy using quantitative diffusion-weighted and dynamic contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hoetker, Andreas M. [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States); Universitaetsmedizin Mainz, Department of Diagnostic and Interventional Radiology, Mainz (Germany); Mazaheri, Yousef [Memorial Sloan-Kettering Cancer Center, Department of Medical Physics, New York, NY (United States); Zheng, Junting; Moskowitz, Chaya S. [Memorial Sloan-Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Berkowitz, Joshua; Pei, Xin; Zelefsky, Michael J. [Memorial Sloan-Kettering Cancer Center, Department of Radiation Oncology, New York, NY (United States); Lantos, Joshua E.; Hricak, Hedvig; Akin, Oguz [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States)

    2015-09-15

    To investigate the effects of androgen-deprivation therapy (ADT) on MRI parameters and evaluate their associations with treatment response measures. The study included 30 men with histopathologically confirmed prostate cancer who underwent MRI before and after initiation of ADT. Thirty-four tumours were volumetrically assessed on DW-MRI (n = 32) and DCE-MRI (n = 18), along with regions of interest in benign prostatic tissue, to calculate apparent diffusion coefficient (ADC) and transfer constant (K{sup trans}) values. Changes in MRI parameters and correlations with clinical parameters (change in prostate-specific antigen [PSA], treatment duration, PSA nadir) were assessed. Prostate volume and PSA values decreased significantly with therapy (p < 0.001). ADC values increased significantly in tumours and decreased in benign prostatic tissue (p < 0.05). Relative changes in ADC and absolute post-therapeutic ADC values differed significantly between tumour and benign tissue (p < 0.001). K{sup trans} decreased significantly only in tumours (p < 0.001); relative K{sup trans} changes and post-therapeutic values were not significantly different between tumour and benign tissue. The relative change in tumour ADC correlated significantly with PSA decrease. No changes were associated with treatment duration or PSA nadir. Multi-parametric MRI shows significant measurable changes in tumour and benign prostate caused by ADT and may help in monitoring treatment response. (orig.)

  12. Prostate cancer: assessing the effects of androgen-deprivation therapy using quantitative diffusion-weighted and dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Hoetker, Andreas M.; Mazaheri, Yousef; Zheng, Junting; Moskowitz, Chaya S.; Berkowitz, Joshua; Pei, Xin; Zelefsky, Michael J.; Lantos, Joshua E.; Hricak, Hedvig; Akin, Oguz

    2015-01-01

    To investigate the effects of androgen-deprivation therapy (ADT) on MRI parameters and evaluate their associations with treatment response measures. The study included 30 men with histopathologically confirmed prostate cancer who underwent MRI before and after initiation of ADT. Thirty-four tumours were volumetrically assessed on DW-MRI (n = 32) and DCE-MRI (n = 18), along with regions of interest in benign prostatic tissue, to calculate apparent diffusion coefficient (ADC) and transfer constant (K trans ) values. Changes in MRI parameters and correlations with clinical parameters (change in prostate-specific antigen [PSA], treatment duration, PSA nadir) were assessed. Prostate volume and PSA values decreased significantly with therapy (p < 0.001). ADC values increased significantly in tumours and decreased in benign prostatic tissue (p < 0.05). Relative changes in ADC and absolute post-therapeutic ADC values differed significantly between tumour and benign tissue (p < 0.001). K trans decreased significantly only in tumours (p < 0.001); relative K trans changes and post-therapeutic values were not significantly different between tumour and benign tissue. The relative change in tumour ADC correlated significantly with PSA decrease. No changes were associated with treatment duration or PSA nadir. Multi-parametric MRI shows significant measurable changes in tumour and benign prostate caused by ADT and may help in monitoring treatment response. (orig.)

  13. 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

  14. 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.)

  15. Independent value of image fusion in unenhanced breast MRI using diffusion-weighted and morphological T2-weighted images for lesion characterization in patients with recently detected BI-RADS 4/5 X-ray mammography findings

    Energy Technology Data Exchange (ETDEWEB)

    Bickelhaupt, Sebastian; Tesdorff, Jana; Delorme, Stefan; Schlemmer, Heinz-Peter [German Cancer Research Center (dkfz), Department of Radiology, Heidelberg (Germany); Laun, Frederik Bernd; Kuder, Tristan Anselm [German Cancer Research Center (dkfz), Medical Physics in Radiology, Heidelberg (Germany); Lederer, Wolfgang; Teiner, Susanne [Radiological Practice at the ATOS Clinic Heidelberg, Heidelberg (Germany); Maier-Hein, Klaus [German Cancer Research Center (dkfz), Junior Group Medical Image Computing, Heidelberg (Germany); Daniel, Heidi [Radiology Center Mannheim (RZM), Mannheim (Germany); Stieber, Anne [University Hospital Heidelberg, Department of Clinical and Interventional Radiology, Heidelberg (Germany)

    2017-02-15

    The aim of this study was to evaluate the accuracy and applicability of solitarily reading fused image series of T2-weighted and high-b-value diffusion-weighted sequences for lesion characterization as compared to sequential or combined image analysis of these unenhanced sequences and to contrast- enhanced breast MRI. This IRB-approved study included 50 female participants with suspicious breast lesions detected in screening X-ray mammograms, all of which provided written informed consent. Prior to biopsy, all women underwent MRI including diffusion-weighted imaging (DWIBS, b = 1500s/mm{sup 2}). Images were analyzed as follows: prospective image fusion of DWIBS and T2-weighted images (FU), side-by-side analysis of DWIBS and T2-weighted series (CO), combination of the first two methods (CO+FU), and full contrast-enhanced diagnostic protocol (FDP). Diagnostic indices, confidence, and image quality of the protocols were compared by two blinded readers. Reading the CO+FU (accuracy 0.92; NPV 96.1 %; PPV 87.6 %) and the CO series (0.90; 96.1 %; 83.7 %) provided a diagnostic performance similar to the FDP (0.95; 96.1 %; 91.3 %; p > 0.05). FU reading alone significantly reduced the diagnostic accuracy (0.82; 93.3 %; 73.4 %; p = 0.023). MR evaluation of suspicious BI-RADS 4 and 5 lesions detected on mammography by using a non-contrast-enhanced T2-weighted and DWIBS sequence protocol is most accurate if MR images were read using the CO+FU protocol. (orig.)

  16. Characterization of the collagen component of cartilage repair tissue of the talus with quantitative MRI: comparison of T2 relaxation time measurements with a diffusion-weighted double-echo steady-state sequence (dwDESS)

    International Nuclear Information System (INIS)

    Kretzschmar, M.; Hainc, N.; Studler, U.; Bieri, O.; Miska, M.; Wiewiorski, M.; Valderrabano, V.

    2015-01-01

    The purpose of this study was to characterize the collagen component of repair tissue (RT) of the talus after autologous matrix-induced chondrogenesis (AMIC) using quantitative T2 and diffusion-weighted imaging. Mean T2 values and diffusion coefficients of AMIC-RT and normal cartilage of the talus of 25 patients with posttraumatic osteochondral lesions and AMIC repair were compared in a cross-sectional design using partially spoiled steady-state free precession (pSSFP) for T2 quantification, and diffusion-weighted double-echo steady-state (dwDESS) for diffusion measurement. RT and cartilage were graded with modified Noyes and MOCART scores on morphological sequences. An association between follow-up interval and quantitative MRI measures was assessed using multivariate regression, after stratifying the cohort according to time interval between surgery and MRI. Mean T2 of the AMIC-RT and cartilage were 43.1 ms and 39.1 ms, respectively (p = 0.26). Mean diffusivity of the RT (1.76 μm 2 /ms) was significantly higher compared to normal cartilage (1.46 μm 2 /ms) (p = 0.0092). No correlation was found between morphological and quantitative parameters. RT diffusivity was lowest in the subgroup with follow-up >28 months (p = 0.027). Compared to T2-mapping, dwDESS demonstrated greater sensitivity in detecting differences in the collagen matrix between AMIC-RT and cartilage. Decreased diffusivity in patients with longer follow-up times may indicate an increased matrix organization of RT. (orig.)

  17. Characterization of the collagen component of cartilage repair tissue of the talus with quantitative MRI: comparison of T2 relaxation time measurements with a diffusion-weighted double-echo steady-state sequence (dwDESS)

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, M.; Hainc, N.; Studler, U. [University Hospital Basel, Department of Radiology, Basel (Switzerland); Bieri, O. [University Hospital Basel, Division of Radiological Physics, Basel (Switzerland); Miska, M. [University Hospital, Department of Orthopedics, Heidelberg (Germany); Wiewiorski, M.; Valderrabano, V. [University Hospital Basel, Department of Orthopedic Surgery, Basel (Switzerland)

    2015-04-01

    The purpose of this study was to characterize the collagen component of repair tissue (RT) of the talus after autologous matrix-induced chondrogenesis (AMIC) using quantitative T2 and diffusion-weighted imaging. Mean T2 values and diffusion coefficients of AMIC-RT and normal cartilage of the talus of 25 patients with posttraumatic osteochondral lesions and AMIC repair were compared in a cross-sectional design using partially spoiled steady-state free precession (pSSFP) for T2 quantification, and diffusion-weighted double-echo steady-state (dwDESS) for diffusion measurement. RT and cartilage were graded with modified Noyes and MOCART scores on morphological sequences. An association between follow-up interval and quantitative MRI measures was assessed using multivariate regression, after stratifying the cohort according to time interval between surgery and MRI. Mean T2 of the AMIC-RT and cartilage were 43.1 ms and 39.1 ms, respectively (p = 0.26). Mean diffusivity of the RT (1.76 μm{sup 2}/ms) was significantly higher compared to normal cartilage (1.46 μm{sup 2}/ms) (p = 0.0092). No correlation was found between morphological and quantitative parameters. RT diffusivity was lowest in the subgroup with follow-up >28 months (p = 0.027). Compared to T2-mapping, dwDESS demonstrated greater sensitivity in detecting differences in the collagen matrix between AMIC-RT and cartilage. Decreased diffusivity in patients with longer follow-up times may indicate an increased matrix organization of RT. (orig.)

  18. Pre-operative assessment of residual disease in locally advanced breast cancer patients: A sequential study by quantitative diffusion weighted MRI as a function of therapy.

    Science.gov (United States)

    Agarwal, Khushbu; Sharma, Uma; Sah, Rani G; Mathur, Sandeep; Hari, Smriti; Seenu, Vurthaluru; Parshad, Rajinder; Jagannathan, Naranamangalam R

    2017-10-01

    The potential of diffusion weighted imaging (DWI) in assessing pathologic response and surgical margins in locally advanced breast cancer patients (n=38) undergoing neoadjuvant chemotherapy was investigated. DWI was performed at pre-therapy (Tp0), after I (Tp1) and III (Tp3) NACT at 1.5T. Apparent diffusion coefficient (ADC) of whole tumor (ADC WT ), solid tumor (ADC ST ), intra-tumoral necrosis (ADC Nec ) was determined. Further, ADC of 6 consecutive shells (5mm thickness each) including tumor margin to outside tumor margins (OM1 to OM5) was calculated and the data analyzed to define surgical margins. Of 38 patients, 6 were pathological complete responders (pCR), 19 partial responders (pPR) and 13 were non-responders (pNR). Significant increase was observed in ADC ST and ADC WT in pCR and pPR following therapy. Pre-therapy ADC was significantly lower in pCR compared to pPR and pNR indicating the heterogeneous nature of tumor which may affect drug perfusion and consequently the response. ADC of outside margins (OM1, OM2, and OM3) was significantly different among pCR, pPR and pNR at Tp3 which may serve as response predictive parameter. Further, at Tp3, ADC of outside margins (OM1, OM2, and OM3) was significantly lower compared to that seen at Tp0 in pCR, indicating the presence of residual disease in these shells. Pre-surgery information may serve as a guide to define cancer free margins and the extent of residual disease which may be useful in planning breast conservation surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Anatomical and functional volume concordance between FDG PET, and T2 and diffusion-weighted MRI for cervical cancer: a hybrid PET/MR study

    International Nuclear Information System (INIS)

    Sun, Hongzan; Xin, Jun; Zhang, Shaomin; Guo, Qiyong; Lu, Yueyue; Zhai, Wei; Zhao, Long; Peng, Weiai; Wang, Baijun

    2014-01-01

    To evaluate the concordance among 18 F-FDG PET imaging, MR T2-weighted (T2-W) imaging and apparent diffusion coefficient (ADC) maps with diffusion-weighted (DW) imaging in cervical cancer using hybrid whole-body PET/MR. This study prospectively included 35 patients with cervical cancer who underwent pretreatment 18 F-FDG PET/MR imaging. 18 F-FDG PET and MR images were fused using standard software. The percent of the maximum standardized uptake values (SUV max ) was used to contour tumours on PET images, and volumes were calculated automatically. Tumour volumes measured on T2-W and DW images were calculated with standard techniques of tumour area multiplied by the slice profile. Parametric statistics were used for data analysis. FDG PET tumour volumes calculated using SUV max (14.30 ± 4.70) and T2-W imaging volume (33.81 ± 27.32 cm 3 ) were similar (P > 0.05) at 35 % and 40 % of SUV max (32.91 ± 18.90 cm 3 and 27.56 ± 17.19 cm 3 respectively) and significantly correlated (P 3 . DW volumes were not significantly different from FDG PET volumes at either 35 % SUV max or 40 % SUV max or from T2-W imaging volumes (P > 0.05). PET subvolumes with increasing SUV max cut-off percentage showed an inverse change in mean ADC values on DW imaging (P max is recommended for 18 F-FDG PET/MR SUV-based tumour volume estimation. The linear tumour subvolume concordance between FDG PET and DW imaging demonstrates individual regional concordance of metabolic activity and cell density. (orig.)

  20. Diagnostic value of sonography, ultrasound-guided fine-needle aspiration cytology, and diffusion-weighted MRI in the characterization of cold thyroid nodules

    Energy Technology Data Exchange (ETDEWEB)

    Schueller-Weidekamm, Claudia [Department of Diagnostic Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)], E-mail: claudia.schueller-weidekamm@meduniwien.ac.at; Schueller, Gerd [Department of Diagnostic Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Kaserer, Klaus [Department of Pathology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Scheuba, Christian [Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Ringl, Helmut; Weber, Michael; Czerny, Christian; Herneth, Andreas M. [Department of Diagnostic Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2010-03-15

    Introduction: The purpose of this prospective study was to assess the diagnostic value of different modalities for the characterization of cold thyroid nodules. Methods: In 35 patients with cold nodules, thyroid carcinoma was suspected on scintigraphy. These patients were prospectively investigated with sonography, ultrasound-guided fine-needle aspiration (USgFNA), and quantitative diffusion-weighted imaging magnetic resonance imaging (DWI) (navigated echo-planar imaging; maximum b-value 800 s/mm{sup 2}) prior to surgery. The sonographic findings, USgFNA cytology, and the apparent diffusion coefficient (ADC) values of DWI were correlated with the postoperative histology of benign and malignant lesions. Statistical analysis was performed with the Kruskal-Wallis test and the Fisher's exact test. P < .05 denoted statistical significance. Results: The accuracy of sonography and USgFNA was 64% and 68.8%, respectively. The sensitivity was 86.7% and 80%, respectively. Specificity was only 57.2% and 50%, respectively. The median ADC values for carcinoma and adenoma were 2.73 x 10{sup -3} mm{sup 2}/s and 1.93 x 10{sup -3} mm{sup 2}/s, respectively (P < .001). There was no significant difference between the median ADC value for Hashimoto thyroiditis (3.46 x 10{sup -3} mm{sup 2}/s) and carcinoma. An ADC value of 2.25 x 10{sup -3} mm{sup 2}/s or higher was proven to be the cut-off value for differentiating between benign and malignant cold thyroid nodules, with an accuracy of 88%, a sensitivity of 85%, and a specificity of 100%. Conclusions: These results show that quantitative DWI is a more reliable diagnostic method for differentiation between benign and malignant thyroid lesions than sonography or USgFNA. However, further studies including a larger study population are necessary to confirm our study results.

  1. Anatomical and functional volume concordance between FDG PET, and T2 and diffusion-weighted MRI for cervical cancer: a hybrid PET/MR study

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hongzan; Xin, Jun; Zhang, Shaomin; Guo, Qiyong; Lu, Yueyue; Zhai, Wei; Zhao, Long [Shengjing Hospital of China Medical University, Department of Radiology, Shenyang, Liaoning (China); Peng, Weiai [NM Marketing, Great China, Philips Healthcare, Guangzhou (China); Wang, Baijun [Philips China Investment Co. Ltd. Shenyang Office, Shenyang, Liaoning (China)

    2014-05-15

    To evaluate the concordance among {sup 18}F-FDG PET imaging, MR T2-weighted (T2-W) imaging and apparent diffusion coefficient (ADC) maps with diffusion-weighted (DW) imaging in cervical cancer using hybrid whole-body PET/MR. This study prospectively included 35 patients with cervical cancer who underwent pretreatment {sup 18}F-FDG PET/MR imaging. {sup 18}F-FDG PET and MR images were fused using standard software. The percent of the maximum standardized uptake values (SUV{sub max}) was used to contour tumours on PET images, and volumes were calculated automatically. Tumour volumes measured on T2-W and DW images were calculated with standard techniques of tumour area multiplied by the slice profile. Parametric statistics were used for data analysis. FDG PET tumour volumes calculated using SUV{sub max} (14.30 ± 4.70) and T2-W imaging volume (33.81 ± 27.32 cm{sup 3}) were similar (P > 0.05) at 35 % and 40 % of SUV{sub max} (32.91 ± 18.90 cm{sup 3} and 27.56 ± 17.19 cm{sup 3} respectively) and significantly correlated (P < 0.001; r = 0.735 and 0.766). The mean DW volume was 30.48 ± 22.41 cm{sup 3}. DW volumes were not significantly different from FDG PET volumes at either 35 % SUV{sub max} or 40 % SUV{sub max} or from T2-W imaging volumes (P > 0.05). PET subvolumes with increasing SUV{sub max} cut-off percentage showed an inverse change in mean ADC values on DW imaging (P < 0.001, ANOVA). Hybrid PET/MR showed strong volume concordance between FDG PET, and T2-W and DW imaging in cervical cancer. Cut-off at 35 % or 40 % of SUV{sub max} is recommended for {sup 18}F-FDG PET/MR SUV-based tumour volume estimation. The linear tumour subvolume concordance between FDG PET and DW imaging demonstrates individual regional concordance of metabolic activity and cell density. (orig.)

  2. Hybrid [{sup 18}F]-FDG PET/MRI including non-Gaussian diffusion-weighted imaging (DWI): Preliminary results in non-small cell lung cancer (NSCLC)

    Energy Technology Data Exchange (ETDEWEB)

    Heusch, Philipp [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Köhler, Jens [Univ Duisburg-Essen, Medical Faculty, Department of Medical Oncology, D-45147 Essen (Germany); Wittsack, Hans-Joerg [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Heusner, Till A., E-mail: Heusner@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Buchbender, Christian [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Poeppel, Thorsten D. [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, D-45147 Essen (Germany); Nensa, Felix; Wetter, Axel [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Gauler, Thomas [Univ Duisburg-Essen, Medical Faculty, Department of Medical Oncology, D-45147 Essen (Germany); Hartung, Verena [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, D-45147 Essen (Germany); Lanzman, Rotem S. [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany)

    2013-11-01

    Purpose: To assess the feasibility of non-Gaussian DWI as part of a FDG-PET/MRI protocol in patients with histologically proven non-small cell lung cancer. Material and methods: 15 consecutive patients with histologically proven NSCLC (mean age 61 ± 11 years) were included in this study and underwent whole-body FDG-PET/MRI following whole-body FDG-PET/CT. As part of the whole-body FDG-PET/MRI protocol, an EPI-sequence with 5 b-values (0, 100, 500, 1000 and 2000 s/mm{sup 2}) was acquired for DWI of the thorax during free-breathing. Volume of interest (VOI) measurements were performed to determine the maximum and mean standardized uptake value (SUV{sub max}; SUV{sub mean}). A region of interest (ROI) was manually drawn around the tumor on b = 0 images and then transferred to the corresponding parameter maps to assess ADC{sub mono}, D{sub app} and K{sub app}. To assess the goodness of the mathematical fit R{sup 2} was calculated for monoexponential and non-Gaussian analysis. Spearman's correlation coefficients were calculated to compare SUV values and diffusion coefficients. A Student's t-test was performed to compare the monoexponential and non-Gaussian diffusion fitting (R{sup 2}). Results: T staging was equal between FDG-PET/CT and FDG-PET/MRI in 12 of 15 patients. For NSCLC, mean ADC{sub mono} was 2.11 ± 1.24 × 10{sup −3} mm{sup 2}/s, D{sub app} was 2.46 ± 1.29 × 10{sup −3} mm{sup 2}/s and mean K{sub app} was 0.70 ± 0.21. The non-Gaussian diffusion analysis (R{sup 2} = 0.98) provided a significantly better mathematical fitting to the DWI signal decay than the monoexponetial analysis (R{sup 2} = 0.96) (p < 0.001). SUV{sub max} and SUV{sub mean} of NSCLC was 13.5 ± 7.6 and 7.9 ± 4.3 for FDG-PET/MRI. ADC{sub mono} as well as D{sub app} exhibited a significant inverse correlation with the SUV{sub max} (ADC{sub mono}: R = −0.67; p < 0.01; D{sub app}: R = −0.69; p < 0.01) as well as with SUV{sub mean} assessed by FDG-PET/MRI (ADC{sub mono}: R

  3. Comparison of qualitative and quantitative evaluation of diffusion-weighted MRI and chemical-shift imaging in the differentiation of benign and malignant vertebral body fractures.

    Science.gov (United States)

    Geith, Tobias; Schmidt, Gerwin; Biffar, Andreas; Dietrich, Olaf; Dürr, Hans Roland; Reiser, Maximilian; Baur-Melnyk, Andrea

    2012-11-01

    The objective of our study was to compare the diagnostic value of qualitative diffusion-weighted imaging (DWI), quantitative DWI, and chemical-shift imaging in a single prospective cohort of patients with acute osteoporotic and malignant vertebral fractures. The study group was composed of patients with 26 osteoporotic vertebral fractures (18 women, eight men; mean age, 69 years; age range, 31 years 6 months to 86 years 2 months) and 20 malignant vertebral fractures (nine women, 11 men; mean age, 63.4 years; age range, 24 years 8 months to 86 years 4 months). T1-weighted, STIR, and T2-weighted sequences were acquired at 1.5 T. A DW reverse fast imaging with steady-state free precession (PSIF) sequence at different delta values was evaluated qualitatively. A DW echo-planar imaging (EPI) sequence and a DW single-shot turbo spin-echo (TSE) sequence at different b values were evaluated qualitatively and quantitatively using the apparent diffusion coefficient. Opposed-phase sequences were used to assess signal intensity qualitatively. The signal loss between in- and opposed-phase images was determined quantitatively. Two-tailed Fisher exact test, Mann-Whitney test, and receiver operating characteristic analysis were performed. Sensitivities, specificities, and accuracies were determined. Qualitative DW-PSIF imaging (delta = 3 ms) showed the best performance for distinguishing between benign and malignant fractures (sensitivity, 100%; specificity, 88.5%; accuracy, 93.5%). Qualitative DW-EPI (b = 50 s/mm(2) [p = 1.00]; b = 250 s/mm(2) [p = 0.50]) and DW single-shot TSE imaging (b = 100 s/mm(2) [p = 1.00]; b = 250 s/mm(2) [p = 0.18]; b = 400 s/mm(2) [p = 0.18]; b = 600 s/mm(2) [p = 0.39]) did not indicate significant differences between benign and malignant fractures. DW-EPI using a b value of 500 s/mm(2) (p = 0.01) indicated significant differences between benign and malignant vertebral fractures. Quantitative DW-EPI (p = 0.09) and qualitative opposed-phase imaging (p = 0

  4. [68Ga]DOTATATE PET/MRI and [18F]FDG PET/CT are complementary and superior to diffusion-weighted MR imaging for radioactive-iodine-refractory differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Vrachimis, Alexis; Stegger, Lars; Wenning, Christian; Noto, Benjamin; Konnert, Julia Renate; Riemann, Burkhard; Weckesser, Matthias; Burg, Matthias Christian; Allkemper, Thomas; Heindel, Walter; Schaefers, Michael

    2016-01-01

    The purpose of this study was to determine whether [ 68 Ga]DOTATATE PET/MRI with diffusion-weighted imaging (DWI) can replace or complement [ 18 F]FDG PET/CT in patients with radioactive-iodine (RAI)-refractory differentiated thyroid cancer (DTC). The study population comprised 12 patients with elevated thyroglobulin and a negative RAI scan after thyroidectomy and RAI remnant ablation who underwent both [ 18 F]FDG PET/CT and [ 68 Ga]DOTATATE PET/MRI within 8 weeks of each other. The presence of recurrent cancer was evaluated on a per-patient, per-organ and per-lesion basis. Histology, and prior and follow-up examinations served as the standard of reference. Recurrent or metastatic tumour was confirmed in 11 of the 12 patients. [ 68 Ga]DOTATATE PET(/MRI) correctly identified the tumour burden in all 11 patients, whereas in one patient local relapse was missed by [ 18 F]FDG PET/CT. In the lesion-based analysis, overall lesion detection rates were 79/85 (93 %), 69/85 (81 %) and 27/82 (33 %) for [ 18 F]FDG PET/CT, [ 68 Ga]DOTATATE PET/MRI and DWI, respectively. [ 18 F]FDG PET(/CT) was superior to [ 68 Ga]DOTATATE PET(/MRI) in the overall evaluation and in the detection of pulmonary metastases. In the detection of extrapulmonary metastases, [ 68 Ga]DOTATATE PET(/MRI) showed a higher sensitivity than [ 18 F]FDG PET(/CT), at the cost of lower specificity. DWI achieved only poor sensitivity and was significantly inferior to [ 18 F]FDG PET in the lesion-based evaluation in the detection of both extrapulmonary and pulmonary metastases. [ 18 F]FDG PET/CT was more sensitive than [ 68 Ga]DOTATATE PET/MRI in the evaluation of RAI-refractory DTC, mostly because of its excellent ability to detect lung metastases. In the evaluation of extrapulmonary lesions, [ 68 Ga]DOTATATE PET(/MRI) was more sensitive and [ 18 F]FDG PET(/CT) more specific. Furthermore, DWI did not provide additional information and cannot replace [ 18 F]FDG PET for postoperative monitoring of patients with

  5. Serial cranial ultrasonography or early MRI for detecting preterm brain injury?

    NARCIS (Netherlands)

    Plaisier, Annemarie; Raets, Marlou M A; Ecury-Goossen, Ginette M; Govaert, Paul; Feijen-Roon, Monique; Reiss, Irwin K M; Smit, Liesbeth S; Lequin, Maarten H; Dudink, Jeroen

    OBJECTIVE: To investigate detection ability and feasibility of serial cranial ultrasonography (CUS) and early MRI in preterm brain injury. DESIGN: Prospective cohort study. SETTING: Level III neonatal intensive care unit. PATIENTS: 307 infants, born below 29 weeks of gestation. METHODS: Serial CUS

  6. Subcategorization of Suspicious Breast Lesions (BI-RADS Category 4) According to MRI Criteria: Role of Dynamic Contrast-Enhanced and Diffusion-Weighted Imaging.

    Science.gov (United States)

    Maltez de Almeida, João Ricardo; Gomes, André Boechat; Barros, Thomas Pitangueira; Fahel, Paulo Eduardo; de Seixas Rocha, Mário

    2015-07-01

    The purposes of this study were to investigate whether dynamic contrast-enhanced MRI is adequate for subcategorization of suspicious lesions (BI-RADS category 4) and to evaluate whether use of DWI improves diagnostic performance. The study group was composed of 103 suspicious lesions found in 83 subjects. Patient ages and lesion sizes were compiled, and two radiologists reanalyzed the images; subcategorized the findings as BI-RADS 4A, 4B, or 4C; and calculated apparent diffusion coefficient (ADC) values. The stratified variables were tested by univariate analysis and inserted in two multivariate predictive models, which were used to generate ROC curves and compare AUCs. Positive predictive values (PPVs) for each subcategory and ADC level were calculated, and interobserver agreement was tested. Forty-four (42.7%) suspicious findings proved malignant. Except for age (p = 0.08), all stratified predictor variables were significant in univariate analyses (p BI-RADS 4 subcategory (4A, 0.15; 4B, 0.37; 4C, 0.84). ADC values of 1.10 × 10(-3) mm(2)/s or less had the second highest PPV (0.77). Interobserver agreement was substantial at a kappa value of 0.80 (95% CI, 0.70-0.90; p BI-RADS category 4) can be satisfactorily performed with DCE-MRI and slightly improved when DWI is introduced.

  7. Does registration of serial MRI improve diagnosis of dementia?

    International Nuclear Information System (INIS)

    Barnes, Josephine; Kennedy, Jonathan; Barker, Suzie; Lehmann, Manja; Nordstrom, R.C.; Smith, Joseph R.; Rossor, Martin N.; Fox, Nick C.; Mitchell, L.A.; Bastos-Leite, Antonio J.; Frost, Chris; Garde, Ellen

    2010-01-01

    We aimed to assess the value of a second MR scan in the radiological diagnosis of dementia. One hundred twenty subjects with clinical follow-up of at least 1 year with two scans were selected from a cognitive disorders clinic. Scans were reviewed as a single first scan (method A), two unregistered scans presented side-by-side (method B) and a registered pair (method C). Scans were presented to two neuroradiologists and a clinician together with approximate scan interval (if applicable) and age. Raters decided on a main and subtype diagnosis. There was no evidence that differences between methods (expressed as relative odds of a correct response) differed between reviewers (p = 0.17 for degenerative condition or not, p = 0.5 for main diagnosis, p = 0.16 for subtype). Accordingly, results were pooled over reviewers. For distinguishing normal/non-progressors from degenerative conditions, the proportions correctly diagnosed were higher with methods B and C than with A (p = 0.001, both tests). The difference between method B and C was not statistically significant (p = 0.18). For main diagnosis, the proportion of correct diagnoses were highest with method C for all three reviewers; however, this was not statistically significant comparing with method A (p = 0.23) or with method B (p = 0.16). For subtype diagnosis, there was some evidence that method C was better than method A (p = 0.01) and B (p = 0.048). Serial MRI and registration may improve visual diagnosis in dementia. (orig.)

  8. SU-E-P-33: Critical Role of T2-Weighted Imaging Combined with Diffusion-Weighted Imaging of MRI in Diagnosis of Loco-Regional Recurrent Esophageal Cancer After Radical Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Deng, G; Qiao, L [Department of Oncology, Shandong University School of Medicine, Jinan, Shandong (China); Liang, N; Xie, J; Zhang, J [Department of Radiation Oncology, Qianfoshan Hospital Affiliated to Shandon, Jinan, Shandong (China); Luo, H; Zhang, J [Division of Oncology, Department of Graduate, Weifang Medical College, Weifang, Shandong (China)

    2015-06-15

    Purpose: We perform this study to investigate the diagnostic efficacy of T2-weighted MRI (T2WI) and diffusion-weighted MRI (DWI) in confirming local relapses of esophageal cancer in patients highly suspected of recurrence after eradicating surgery. Methods: Forty-two postoperative esophageal cancer patients with clinical suspicions of cancer recurrence underwent 3.0T MRI applying axial, coronal, sagittal T2WI and axial DWI sequences. Two experienced radiologists (R1 and R2) both used two methods (T2WI, T2WI+DWI) to observe the images, and graded the patients ranging from 1 to 5 to represent severity of the disease based on visual signal intensity (patients equal to or more than grade 3 was confirmed as recurrent disease) Results: 27/42patients were verified of recurrent disease by pathologic findings and/or imaging findings during follow-up. The sensitivity, specificity and accuracy of R1 applying T2WI+DWI are 96%, 87% and 93% versus 81%, 80% and 77% on T2WI, these figures by R2 were 96%, 93% and 95% versus 89%, 93% and 90%. The receiver operating curve (ROC) analyses suggest that both of the two readers can obtain better accuracy when adding DWI to T2WI compared with T2WI alone. Kappa test between R1 and R2 indicates excellent inter-observer agreement on T2WI+DWI. Conclusion: Standard T2WI in combination DWI can achieve better accuracy than T2WI alone in diagnosing local recurrence of esophageal cancer, and improve consistency between different readers.

  9. 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.

  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. Clinical relevance of the apparent diffusion coefficient value of metastatic bone tumours on diffusion-weighted MRI images: differences according to the types of primary tumour, the affected bones, and clinical factors.

    Science.gov (United States)

    Cha, M J; Yoon, Y C

    2015-10-01

    To evaluate whether the apparent diffusion coefficient (ADC) of metastatic bone tumours on diffusion-weighted magnetic resonance imaging (MRI) images differs according to the type of primary cancer, the affected bone, and clinical factors. For this retrospective study, two radiologists reviewed MRI images, including ADC maps, of 67 patients (M:F=38:29; median age, 48 years) who were diagnosed with bone metastasis by means of histological or clinical confirmation. The primary tumours included 29 lung adenocarcinomas, 15 invasive ductal adenocarcinomas of the breast, 13 hepatocellular carcinomas, six prostatic carcinomas, and four renal cell carcinomas. ADC values of the metastatic tumour were compared according to the type of primary malignancy, the affected bone, and the age and sex of the patient using Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction. In addition, pre-contrast CT images were available in 38 of 67 patients; a subanalysis of the CT radiodensity and ADC values were performed with Spearman correlation. The mean, standard deviation, and minimum and maximum values of the ADC of metastatic bone tumours did not differ significantly according to type of primary malignancy, the affected bone, or clinical variables (p>0.1). The ADC value was not significantly correlated with CT radiodensity (p=0.24). Intra- and interobserver agreements for the mean ADC values were excellent (intra-observer: p=0.98; interobserver: p=0.98). Assessment of the ADC value of metastatic bone tumours is not reliable for differentiation of the type of primary cancer. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  12. MRI of head trauma. Serial changes and comparison with CT

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Osamu; Sato, Shuji; Suzuki, Takashi; Endo, Shunro; Takaku, Akira.

    1988-08-01

    Sequential changes in magnetic resonance imaging (MRI) were investigated in comparison with computed tomography (CT) in 31 cases of head trauma. Twenty-one of them were of acute head trauma; the first MRI study was performed within 48 hours after the accident. Forty-two intracranial lesions were observed in these cases on MRI. The other 10 cases were of chronic subdural hematoma, two cases of which had bilateral lesions. Fourteen lesions of acute head trauma and two lesions of chronic subdural hematoma were detected only by MRI. MRI was superior to CT for the detection of small contusions and thin extra-axial collections, especially those which were located near the bony structures. The abnormal lesions were visualized in MRI during a longer period than in CT. Because the signal intensity of a hematoma changed sequentially, the detection of brain edema was easier than that of a subarachnoid and parenchimal hemorrhage. Judging from this experience, it seems that careful attention should be taken in the diagnosis of hemorrhagic lesions. However, MRI was poor in tissue characterization because of the too-high tissue sensitivity. T/sub 2/-weight SE imaging was essentially sensitive and useful in the early stage.

  13. 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

  14. 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

  15. 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

  16. 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

  17. Diffusion weighted MRI and 18F-FDG PET/CT in non-small cell lung cancer (NSCLC): Does the apparent diffusion coefficient (ADC) correlate with tracer uptake (SUV)?

    International Nuclear Information System (INIS)

    Regier, M.; Derlin, T.; Schwarz, D.; Laqmani, A.; Henes, F.O.; Groth, M.; Buhk, J.-H.; Kooijman, H.; Adam, G.

    2012-01-01

    Introduction: To investigate the potential correlation of the apparent diffusion coefficient assessed by diffusion-weighted MRI (DWI) and glucose metabolism determined by the standardized uptake value (SUV) at 18F-FDG PET/CT in non-small cell lung cancer (NSCLC). Materials and methods: 18F-FDG PET/CT and DWI (TR/TE, 2000/66 ms; b-values, 0 and 500 s/mm 2 ) were performed in 41 consecutive patients with histologically verified NSCLC. Analysing the PET-CT data calculation of the mean (SUV mean ) and maximum (SUV max ) SUV was performed. By placing a region-of-interest (ROI) encovering the entire tumor mean (ADC mean ) and minimum ADC (ADC min ) were determined by two independent radiologists. Results of 18F-FDG PET-CT and DWI were compared on a per-patient basis. For statistical analysis Pearson's correlation coefficient, Bland–Altman and regression analysis were assessed. Results: Data analysis revealed a significant inverse correlation of the ADC min and SUV max (r = −0.46; p = 0.032). Testing the correlation of the ADC min and SUV max for each histological subtype separately revealed that the inverse correlation was good for both adenocarcinomas (r = −0.47; p = 0.03) and squamouscell carcinomas (r = −0.71; p = 0.002), respectively. No significant correlation was found for the comparison of ADC min and SUV mean (r = −0.29; p = 0.27), ADC mean vs. SUV mean (r = −0.28; p = 0.31) or ADC mean vs. SUV max (r = −0.33; p = 0.23). The κ-value of 0.88 indicated a good agreement between both observers. Conclusion: This preliminary study is the first to verify the relation between the SUV and the ADC in NSCLC. The significant inverse correlation of these two quantitative imaging approaches points out the association of metabolic activity and tumor cellularity. Therefore, DWI with ADC measurement might represent a new prognostic marker in NSCLC

  18. Serial MRI in a case of familial hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Butteriss, D.J.A.; Birchall, D. [Department of Neuroradiology, Regional Neurosciences Centre Newcastle General Hospital, Westgate Road, NE4 6BE, Newcastle upon Tyne (United Kingdom); Ramesh, V. [Department of Paediatric Neurology, Regional Neurosciences Centre Newcastle General Hospital, Westgate Road, NE4 6BE, Newcastle upon Tyne (United Kingdom)

    2003-05-01

    We report MRI findings in a patient with familial hemiplegic migraine (FHM) with repeated episodes of hemiparesis. FHM is caused by a penetrant autosomal dominant genetic mutation; several mutations have been genotyped, involving brain-expressed ion channels. We found cerebral oedema, dilatation of intracerebral vessels and decreased water diffusion contralateral to the hemiparesis, not respecting vascular territories, with subsequent complete resolution of both clinical and imaging abnormalities. These results are thought to be consistent with an underlying primary neuronal pathology with secondary vascular effects, as opposed to the traditional, primarily vascular, model of migraine aetiology. (orig.)

  19. Laminectomy-induced arachnoradiculitis: a postoperative serial MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, H [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Tsuji, H [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Kanamori, M [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Kawaguchi, Y [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Yudoh, K [Departments of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan); Futatsuya, R [Departments of Radiology, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Toyama (Japan)

    1995-11-01

    Time-related changes of laminectomy-induced cauda equina adhesions were investigated by MRI in ten patients with degenerative spinal disease who underwent posterior surgery to the lumbar spine; seven had disc herniations and three spinal stenosis. Axial MRI was performed before and 3, 7, 21 and 42 days after surgery. Cauda equina adhesions were most severe at the laminectomised levels L3-4, L4-5 and L5-S1 (n = 16); partial adhesions were found in 9 of 16 levels at 6 weeks after surgery. At the L3-4 or L5-S1 levels (n = 14), the area of laminar exposure without laminectomy, the cauda equina adhesions continued 1 week after surgery, but thereafter resolved; only partial adhesions were seen at 5 of 14 levels 6 weeks after surgery. Shrinkage of the arachnoid sac was also found at the level of the laminectomy, but it re-expanded 3 weeks after surgery in all cases. Cauda equina adhesions and shrinkage of the sac were correlated closely with laminectomy, with or without discectomy, suggesting that an inflammatory process of deep wound healing may be involved in the mechanism of a laminectomy-induced arachnoradiculitis which may be correlated with postoperative leg symptoms. (orig.). With 7 figs., 1 tab.

  20. Laminectomy-induced arachnoradiculitis: a postoperative serial MRI study

    International Nuclear Information System (INIS)

    Matsui, H.; Tsuji, H.; Kanamori, M.; Kawaguchi, Y.; Yudoh, K.; Futatsuya, R.

    1995-01-01

    Time-related changes of laminectomy-induced cauda equina adhesions were investigated by MRI in ten patients with degenerative spinal disease who underwent posterior surgery to the lumbar spine; seven had disc herniations and three spinal stenosis. Axial MRI was performed before and 3, 7, 21 and 42 days after surgery. Cauda equina adhesions were most severe at the laminectomised levels L3-4, L4-5 and L5-S1 (n = 16); partial adhesions were found in 9 of 16 levels at 6 weeks after surgery. At the L3-4 or L5-S1 levels (n = 14), the area of laminar exposure without laminectomy, the cauda equina adhesions continued 1 week after surgery, but thereafter resolved; only partial adhesions were seen at 5 of 14 levels 6 weeks after surgery. Shrinkage of the arachnoid sac was also found at the level of the laminectomy, but it re-expanded 3 weeks after surgery in all cases. Cauda equina adhesions and shrinkage of the sac were correlated closely with laminectomy, with or without discectomy, suggesting that an inflammatory process of deep wound healing may be involved in the mechanism of a laminectomy-induced arachnoradiculitis which may be correlated with postoperative leg symptoms. (orig.). With 7 figs., 1 tab

  1. Serial changes of humor comprehension for four-frame comic Manga: an fMRI study.

    Science.gov (United States)

    Osaka, Mariko; Yaoi, Ken; Minamoto, Takehiro; Osaka, Naoyuki

    2014-07-25

    Serial changes of humor comprehension evoked by a well organized four-frame comic Manga were investigated by fMRI in each step of humor comprehension. The neural substrates underlying the amusing effects in response to funny and mixed order manga were compared. In accordance with the time course of the four frames, fMRI activations changed serially. Beginning with the second frame (development scene), activation of the temporo-parietal junction (TPJ) was observed, followed by activations in the temporal and frontal areas during viewing of the third frame (turn scene). For the fourth frame (punch line), strong increased activations were confirmed in the medial prefrontal cortex (MPFC) and cerebellum. Interestingly, distinguishable activation differences in the cerebellum between funny and non-funny conditions were also found for the fourth frame. These findings suggest that humor comprehension evokes activation that initiates in the TPJ and expands to the MPFC and cerebellum at the convergence level.

  2. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    Energy Technology Data Exchange (ETDEWEB)

    Rademacher, J.; Seitz, R.J. [Department of Neurology, Heinrich-Heine University Duesseldorf (Germany); Aulich, A. [Department of Radiology, Heinrich-Heine University, Duesseldorf (Germany); Reifenberger, G. [Department of Neuropathology, Heinrich-Heine University, Duesseldorf (Germany); Kiwit, J.C.W. [Department of Neurosurgery, Heinrich-Heine University, Duesseldorf (Germany); Langen, K.J.; Schmidt, D. [Institute of Medicine, Research Center Juelich, Heinrich-Heine University, Duesseldorf (Germany)

    2000-06-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[{sup 123}I]iodo-{alpha}-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  3. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    International Nuclear Information System (INIS)

    Rademacher, J.; Seitz, R.J.; Aulich, A.; Reifenberger, G.; Kiwit, J.C.W.; Langen, K.J.; Schmidt, D.

    2000-01-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[ 123 I]iodo-α-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  4. Central pontine myelinolysis with a hyperintense lesion in diffusion weighted MRI: overview by means of a case report; Zentrale pontine Myelinolyse mit hyperintenser Laesion im diffusionsgewichteten MRT: Uebersicht anhand eines Fallberichtes

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, J.; Bewermeyer, H. [Neurologische Klinik, Kliniken der Stadt Koeln gGmbH, Krankenhaus Merheim, Koeln (Germany); Harzheim, A. [Radiologische Klinik, Kliniken der Stadt Koeln gGmbH, Krankenhaus Merheim, Koeln (Germany)

    2005-07-01

    Central pontine myelinolysis (CPM) is a demyelinating disease of the pons often associated with demyelination of other areas of the central nervous system (CNS). The etiology and pathogenesis of this disorder are still not fully understood. However, almost all cases of CPM are related to severe diseases or chronic alcoholism and occur in the setting of rapidly corrected serum hyponatremia and hypotonicity respectively. Depending on the involvement of other CNS structures, the clinical picture can vary considerably. Magnetic resonance imaging is the most sensitive investigation for the antemortem diagnosis of CPM, although the radiological findings lag behind and do not necessarily correlate with the clinical picture. Quite obviously diffusion-weighted imaging can be useful in the rapid diagnosis of CPM. This short review summarizes the current knowledge on the pathogenesis, clinical presentation, radiological findings, prognosis and therapeutic approaches of CPM. Characteristical clinical features and MR-findings including hyperintensity on diffusion-weighted images are illustrated by a typical case. (orig.)

  5. Visual analysis of serial T2-weighted MRI in multiple sclerosis: intra- and interobserver reproducibility

    International Nuclear Information System (INIS)

    Molyneux, P.D.; Miller, D.H.; Filippi, M.; Yousry, T.A.; Radue, E.W.; Ader, H.J.; Barkhof, F.

    1999-01-01

    We evaluated the effect of consensus formation and training on the agreement between observers in scoring the number of new and enlarging multiple sclerosis (MS) lesions on serial T2-weighted MRI studies. The baseline and month 9 MRI studies of 16 patients with a range of MRI activity were used (dual-echo conventional spin-echo sequence, TR 2000, TE 34 and 90 ms, 5 mm contiguous slices, in-plane resolution 1 mm). First, the serial studies were visually analysed for the presence of new and enlarging lesions, on two occasions, by five experienced observers, without adopting any consensus strategy and in isolation. Next, the observers met to identify the common sources of inconsistencies in reporting between observers and formulate consensus rules. Finally, a further independent reading session was performed on the same MRI dataset, this time applying the consensus rules. Agreement between observers was assessed using kappa scores. Without the consensus rules, interobserver kappa scores for the first and second reading sessions for new lesions were only 0.51 and 0.39 respectively; agreement for enlarging lesions was even worse. The mean intraobserver kappa score for new lesions was higher at 0.72, reflecting the fact that the observers were consistently applying their individual assessment strategies. Application of the consensus rules did not lead to a significant improvement in inter observer kappas; the kappa scores adopting the guidelines were 0.46 and 0.21 for new and enlarging lesions respectively. Consensus guidelines thus did not improve the reproducibility of visual analysis of serial T2-weighted MRI, and the level of agreement between observers remained only moderate. Suboptimal repositioning is likely to be a major source of residual variability and this suggests a future role for image registration strategies; until then, a single observer, or pair of observers working in consensus, should be used in MS studies. (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. 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.)

  8. 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.)

  9. Utility of Diffusion-Weighted MRI to Detect Changes in Liver Diffusion in Benign and Malignant Distal Bile Duct Obstruction: The Influence of Choice of b-Values.

    Science.gov (United States)

    Karan, Belgin; Erbay, Gurcan; Koc, Zafer; Pourbagher, Aysin; Yildirim, Sedat; Agildere, Ahmet Muhtesem

    2016-11-01

    The study sought to evaluate the potential of diffusion-weighted magnetic resonance imaging to detect changes in liver diffusion in benign and malignant distal bile duct obstruction and to investigate the effect of the choice of b-values on apparent diffusion coefficient (ADC). Diffusion-weighted imaging was acquired with b-values of 200, 600, 800, and 1000 s/mm 2 . ADC values were obtained in 4 segments of the liver. The mean ADC values of 16 patients with malignant distal bile duct obstruction, 14 patients with benign distal bile duct obstruction, and a control group of 16 healthy patients were compared. Mean ADC values for 4 liver segments were lower in the malignant obstruction group than in the benign obstruction and control groups using b = 200 s/mm 2 (P liver segments in each group were not significantly different (P > .05). There were no correlations between the ADC values of liver segments and liver function tests. Measurement of ADC shows good potential for detecting changes in liver diffusion in patients with distal bile duct obstruction. Calculated ADC values were affected by the choice of b-values. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  10. Serial MRI findings of osteoporotic vertebral fractures in the thoracic and lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Yoshitaka; Henmi, Tatsuhiko; Sakamoto, Rintaro; Hiasa, Masahiko [Health Insurance Naruto Hospital, Tokushima (Japan)

    1998-12-01

    The prognosis of osteoporotic vertebral fractures in the thoracic and lumbar spine was studied by serial MRI findings. This study covered 80 vertebrae in 69 patients treated conservatively and followed-up for more than six months (23 males and 46 females, average age 70 yrs). Group A, characterized by poor diagnostic imaging, consisted of patients who had both severely collapsed vertebra which was progressive in the lateral roentgenogram and delayed improvement in MRI signal intensities. Group B, consisting of poor clinical prognosis, comprised patients with persistent back pain. The predictive factors for Group A were found to be T{sub 1}-low finding over the entire vertebra within one month after injury and fractures of Th{sub 12} or L{sub 1} vertebra. Areas of T{sub 1}-low and T{sub 2}-low intensity adjacent to the vertebral disc presented no improvement in signal intensity and often caused persistent back pain. (author)

  11. Serial MRI findings of osteoporotic vertebral fractures in the thoracic and lumbar spine

    International Nuclear Information System (INIS)

    Hamada, Yoshitaka; Henmi, Tatsuhiko; Sakamoto, Rintaro; Hiasa, Masahiko

    1998-01-01

    The prognosis of osteoporotic vertebral fractures in the thoracic and lumbar spine was studied by serial MRI findings. This study covered 80 vertebrae in 69 patients treated conservatively and followed-up for more than six months (23 males and 46 females, average age 70 yrs). Group A, characterized by poor diagnostic imaging, consisted of patients who had both severely collapsed vertebra which was progressive in the lateral roentgenogram and delayed improvement in MRI signal intensities. Group B, consisting of poor clinical prognosis, comprised patients with persistent back pain. The predictive factors for Group A were found to be T 1 -low finding over the entire vertebra within one month after injury and fractures of Th 12 or L 1 vertebra. Areas of T 1 -low and T 2 -low intensity adjacent to the vertebral disc presented no improvement in signal intensity and often caused persistent back pain. (author)

  12. Muscle atrophy and metal-on-metal hip implants: a serial MRI study of 74 hips.

    Science.gov (United States)

    Berber, Reshid; Khoo, Michael; Cook, Erica; Guppy, Andrew; Hua, Jia; Miles, Jonathan; Carrington, Richard; Skinner, John; Hart, Alister

    2015-06-01

    Muscle atrophy is seen in patients with metal-on-metal (MOM) hip implants, probably because of inflammatory destruction of the musculo-tendon junction. However, like pseudotumors, it is unclear when atrophy occurs and whether it progresses with time. Our objective was to determine whether muscle atrophy associated with MOM hip implants progresses with time. We retrospectively reviewed 74 hips in 56 patients (32 of them women) using serial MRI. Median age was 59 (23-83) years. The median time post-implantation was 83 (35-142) months, and the median interval between scans was 11 months. Hip muscles were scored using the Pfirrmann system. The mean scores for muscle atrophy were compared between the first and second MRI scans. Blood cobalt and chromium concentrations were determined. The median blood cobalt was 6.84 (0.24-90) ppb and median chromium level was 4.42 (0.20-45) ppb. The median Oxford hip score was 34 (5-48). The change in the gluteus minimus mean atrophy score between first and second MRI was 0.12 (p = 0.002). Mean change in the gluteus medius posterior portion (unaffected by surgical approach) was 0.08 (p = 0.01) and mean change in the inferior portion was 0.10 (p = 0.05). Mean pseudotumor grade increased by 0.18 (p = 0.02). Worsening muscle atrophy and worsening pseudotumor grade occur over a 1-year period in a substantial proportion of patients with MOM hip implants. Serial MRI helps to identify those patients who are at risk of developing worsening soft-tissue pathology. These patients should be considered for revision surgery before irreversible muscle destruction occurs.

  13. Serial CT and MRI of ischaemic cerebral infarcts: frequency and clinical impact of haemorrhagic transformation

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, T.E.; Brueckmann, H. [Muenchen Univ. (Germany). Abt. fuer Neuroradiologie; Schulte-Altedorneburg, G. [Dept. of Radiology/Neuroradiology, University Medical School of Luebeck (Germany); Droste, D.W. [Dept. of Neurology, University Medical School of Luebeck (Germany)

    2000-04-01

    The frequency, predisposing factors and clinical consequences of haemorrhagic infarcts and damaged blood-brain barrier as shown by contrast enhancement (CE) in ischaemic cerebral infarcts are controversial. We prospectively compared the sensitivity of CT and MRI to haemorrhagic transformation (HT) and CE. We also wished to investigate the clinical significance of HT and factors possibly associated with it. We studied 36 patients with acute ischaemic infarcts in the middle cerebral artery territory during the first 2 weeks after the ictus. After CT and rating of the neurological deficit on admission, serial examinations with clinical neuromonitoring, contrast-enhanced CT and MRI were done on the same day. The occurrence and severity of HT were correlated with CE, stroke mechanism, infarct size, development of neurological deficits and antithrombotic treatment. The frequency of HT detected by MRI was 80 %. CE usually preceded HT or was seen simultaneously. MRI had a higher sensitivity than CT to HT and CE. Severity of HT was positively correlated with infarct size (P < 0.01). HT had no influence on patient's neurological status. Neither the type of antithrombotic treatment nor the stroke mechanism was associated with the severity of HT. No parenchymal haemorrhage occurred. (orig.)

  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. 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 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

  18. 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)

  19. 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.)

  20. 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.)

  1. Sjoegren's syndrome of the parotid gland: value of diffusion-weighted echo-planar MRI for diagnosis at an early stage based on MR sialography grading in comparison with healthy volunteers

    International Nuclear Information System (INIS)

    Regier, Marc; Ries, T.; Arndt, C.; Cramer, M.C.; Adam, G.; Habermann, C.R.; Graessner, J.; Reitmeier, F.; Jaehne, M.

    2009-01-01

    To investigate the value of diffusion-weighted echo-planar imaging (DW-EPI) for quantifying functional changes of the parotid gland in Sjoegren's disease and to evaluate whether ADC mapping allows for early diagnosis based on MR sialography grading. Using a DW-EPI sequence at 1.5T (b-factors: 0, 500 and 1000 sec/mm 2 ), the parotid glands of 52 healthy volunteers and 13 patients with histologically verified affection of Sjoegren's disease were examined. All scans were performed prior to and following gustatory stimulation with 5 ml of lemon juice. ADC maps were evaluated by placing an inordinate region-of-interest (ROI) enclosing the entire parotid gland. Sjoegren's disease was graded based on MR sialography findings using a 4-point grading-scale. Statistics included student t-test and kappa-analysis. In healthy volunteers mean ADCs of 1.14 x 10 -3 mm 2 /sec before and 1.2 x 10 -3 mm 2 /sec after stimulation were observed. Higher ADCs were determined for early-stage Sjoegren's disease, averaging 1.22 x 10 -3 mm 2 /sec before and 1.29 x 10 -3 mm 2 /sec after stimulation. Advanced disease revealed significantly lower ADCs (0.97 x 10 -3 mm 2 /sec (p = 0.002) before and 1.01 x 10 -3 mm 2 /sec (p < 0.001) after stimulation). (orig.)

  2. Serial MRI and MRS studies with unusual findings in Rasmussen's encephalitis

    International Nuclear Information System (INIS)

    Tuerkdogan-Soezueer, D.; Oezek, M.M.; Pamir, M.N.; Sav, A.; Dincer, A.

    2000-01-01

    Rasmussen's syndrome is characterized by intractable seizures and progressive neuropsychiatric deterioration secondary to unilateral cortical inflammation and tissue destruction. Diagnosis of Rasmussen's syndrome in the early phase depends mainly on the clinical features. Neuroimaging and histopathologic examinations may not be specific during this period. We report a case of Rasmussen's syndrome followed by serial MRI and magnetic resonance spectroscopy (MRS) studies over a 3- to 16-month period. A healthy 6-year-old boy presented with focal motor seizures. An MRI study demonstrated prominent enlargement and T2 hyperintensity of the left mesial temporal lobe and perisylvian region. This early finding evolved to volume loss and later progressive atrophy of the ipsilateral hemisphere when epilepsia partialis continua occurred. Being aware of those early MRI features in a patient with increasing frequency of focal motor seizures should suggest Rasmussen's syndrome. In addition, we found prominently increased myoinositol concentration in atrophic cortex which might reflect increased gliosis in the late period of the disease. (orig.)

  3. Serial MRI and MRS studies with unusual findings in Rasmussen's encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Tuerkdogan-Soezueer, D. [Department of Pediatric Neurology, Institute of Neurological Sciences, Marmara University, Istanbul (Turkey); Oezek, M.M.; Pamir, M.N. [Department of Neurosurgery, Institute of Neurological Sciences, Marmara University, Istanbul (Turkey); Sav, A. [Department of Pathology, Institute of Neurological Sciences, Marmara University, Istanbul (Turkey); Dincer, A. [Radyomar MR Center, Istanbul (Turkey)

    2000-06-01

    Rasmussen's syndrome is characterized by intractable seizures and progressive neuropsychiatric deterioration secondary to unilateral cortical inflammation and tissue destruction. Diagnosis of Rasmussen's syndrome in the early phase depends mainly on the clinical features. Neuroimaging and histopathologic examinations may not be specific during this period. We report a case of Rasmussen's syndrome followed by serial MRI and magnetic resonance spectroscopy (MRS) studies over a 3- to 16-month period. A healthy 6-year-old boy presented with focal motor seizures. An MRI study demonstrated prominent enlargement and T2 hyperintensity of the left mesial temporal lobe and perisylvian region. This early finding evolved to volume loss and later progressive atrophy of the ipsilateral hemisphere when epilepsia partialis continua occurred. Being aware of those early MRI features in a patient with increasing frequency of focal motor seizures should suggest Rasmussen's syndrome. In addition, we found prominently increased myoinositol concentration in atrophic cortex which might reflect increased gliosis in the late period of the disease. (orig.)

  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. 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)

  6. Sjoegren's syndrome of the parotid gland: value of diffusion-weighted echo-planar MRI for diagnosis at an early stage based on MR sialography grading in comparison with healthy volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Regier, Marc; Ries, T.; Arndt, C.; Cramer, M.C.; Adam, G.; Habermann, C.R. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Graessner, J. [Siemens AG, Hamburg (Germany). Medical Solutions; Reitmeier, F.; Jaehne, M. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenheilkunde

    2009-03-15

    To investigate the value of diffusion-weighted echo-planar imaging (DW-EPI) for quantifying functional changes of the parotid gland in Sjoegren's disease and to evaluate whether ADC mapping allows for early diagnosis based on MR sialography grading. Using a DW-EPI sequence at 1.5T (b-factors: 0, 500 and 1000 sec/mm{sup 2}), the parotid glands of 52 healthy volunteers and 13 patients with histologically verified affection of Sjoegren's disease were examined. All scans were performed prior to and following gustatory stimulation with 5 ml of lemon juice. ADC maps were evaluated by placing an inordinate region-of-interest (ROI) enclosing the entire parotid gland. Sjoegren's disease was graded based on MR sialography findings using a 4-point grading-scale. Statistics included student t-test and kappa-analysis. In healthy volunteers mean ADCs of 1.14 x 10{sup -3} mm{sup 2} /sec before and 1.2 x 10{sup -3} mm{sup 2} /sec after stimulation were observed. Higher ADCs were determined for early-stage Sjoegren's disease, averaging 1.22 x 10{sup -3} mm{sup 2} /sec before and 1.29 x 10{sup -3} mm{sup 2} /sec after stimulation. Advanced disease revealed significantly lower ADCs (0.97 x 10{sup -3} mm{sup 2} /sec (p = 0.002) before and 1.01 x 10{sup -3} mm{sup 2} /sec (p < 0.001) after stimulation). (orig.)

  7. 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.

  8. Consistency of parametric registration in serial MRI studies of brain tumor progression

    International Nuclear Information System (INIS)

    Mang, Andreas; Buzug, Thorsten M.; Schnabel, Julia A.; Crum, William R.; Modat, Marc; Ourselin, Sebastien; Hawkes, David J.; Camara-Rey, Oscar; Palm, Christoph; Caseiras, Gisele Brasil; Jaeger, H.R.

    2008-01-01

    The consistency of parametric registration in multi-temporal magnetic resonance (MR) imaging studies was evaluated. Serial MRI scans of adult patients with a brain tumor (glioma) were aligned by parametric registration. The performance of low-order spatial alignment (6/9/12 degrees of freedom) of different 3D serial MR-weighted images is evaluated. A registration protocol for the alignment of all images to one reference coordinate system at baseline is presented. Registration results were evaluated for both, multimodal intra-timepoint and mono-modal multi-temporal registration. The latter case might present a challenge to automatic intensity-based registration algorithms due to ill-defined correspondences. The performance of our algorithm was assessed by testing the inverse registration consistency. Four different similarity measures were evaluated to assess consistency. Careful visual inspection suggests that images are well aligned, but their consistency may be imperfect. Sub-voxel inconsistency within the brain was found for allsimilarity measures used for parametric multi-temporal registration. T1-weighted images were most reliable for establishing spatial correspondence between different timepoints. The parametric registration algorithm is feasible for use in this application. The sub-voxel resolution mean displacement error of registration transformations demonstrates that the algorithm converges to an almost identical solution for forward and reverse registration. (orig.)

  9. 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.…

  10. 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...

  11. Superselective intra-arterial fibrinolysis for acute cerebral ischemic infarct : usefulness of diffusion weighted MR imaging

    International Nuclear Information System (INIS)

    Byun, Woo Mok; Lee, Se Jin; Kim, Yong Sun; Han, Gun Soo; Bae, Won Kyong

    1999-01-01

    To evaluate the efficacy of superselective intra-arterial fibrinolysis for acute cerebral stroke and the usefulness of pre-and postfibrinolysis diffusion-weighted MRI (DWI). In 41 patients with acute ischemic stroke whose treatment involved intra-arterial fibrinolysis, the occlusion site, degree of recanalization, and clinical results were compared. In 12 patients, diffusion weighted MRI was performed before fibrinolysis, and eight of these also underwent diffusion-weighted MRI after fibrinolysis. Using diffusion-weighted MRI, neurological outcomes were compared with signal intensity ratio (SIR, or the average signal intensity within the region of interest divided by that in the contralateral, nonischemic, homologous region). Twenty patients showed complete recanalization, nine partial recanalization, and in twelve there was no recanalization. Fourteen patients (34%) improved neurologically. No relationship existed between occlusion sites, degree of recanalization, and clinical outcome. Among 12 patients who underwent DWI before fibrinolysis, complete recanalization was noted in eight. Neurological improvement was seen in four patients with low SIR( 1.7), neurological outcome was poor despite complete recanalization. Although superselective intra-arterial fibrinolysis for acute cerebral stroke is a good therapeutic method for recanalization, the clinical outcome can be disappointing. We therefore suggest that in cases of acute cerebral ischemic infaret, SIR-as seen on DWI-might be useful for predicting the benefits of recanalization. In such cases, further investigation of the use of DWI prior to fibrinolysis is therefore needed

  12. Study of diffusion weighted MRI as a predictive biomarker of response during radiotherapy for high and intermediate risk squamous cell cancer of the oropharynx: The MeRInO study

    Directory of Open Access Journals (Sweden)

    C Paterson

    2017-02-01

    Discussion: The use of DW-MRI as a predictive biomarker during RT for SCC H&N is in its infancy but studies to date have found that response to treatment may indeed be predicted by comparison of DW-MRI carried out before and during treatment. However, previous studies have included all sub-sites and biological sub-types. Establishing ADC thresholds that predict for local failure is an essential step towards using DW-MRI to improve the therapeutic ratio in treating SCC H&N. This would be done most robustly in a specific H&N sub-site and in sub-types with similar biological behaviour. The MeRInO study will help establish these thresholds in OPSCC.

  13. Serial prenatal and postnatal MRI of dystroglycanopathy in a patient with familial B3GALNT2 mutation

    International Nuclear Information System (INIS)

    Ho, Mai-Lan; Glenn, Orit A.; Sherr, Eliott H.; Strober, Jonathan B.

    2017-01-01

    The dystroglycanopathies are a heterogeneous group of conditions, with mutations in B3GALNT2 described in association with congenital muscular dystrophy. The serial prenatal MRI findings in this disorder have not been well described. We present sequential prenatal and postnatal MRI findings in a boy with compound heterozygous mutations in B3GALNT2, as well as the MRI findings of his two siblings with similar mutations. These findings provide new insight into the molecular pathogenesis and neurodevelopment of congenital muscular dystrophy. (orig.)

  14. Serial prenatal and postnatal MRI of dystroglycanopathy in a patient with familial B3GALNT2 mutation

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Mai-Lan [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Glenn, Orit A. [University of California, Department of Radiology, San Francisco, CA (United States); Sherr, Eliott H. [University of California, Department of Neurology, San Francisco, CA (United States); University of California, Department of Pediatrics, San Francisco, CA (United States); Strober, Jonathan B. [University of California, Department of Neurology, San Francisco, CA (United States)

    2017-06-15

    The dystroglycanopathies are a heterogeneous group of conditions, with mutations in B3GALNT2 described in association with congenital muscular dystrophy. The serial prenatal MRI findings in this disorder have not been well described. We present sequential prenatal and postnatal MRI findings in a boy with compound heterozygous mutations in B3GALNT2, as well as the MRI findings of his two siblings with similar mutations. These findings provide new insight into the molecular pathogenesis and neurodevelopment of congenital muscular dystrophy. (orig.)

  15. Quantitative evaluation of benign and malignant vertebral fractures with diffusion-weighted MRI: what is the optimum combination of b values for ADC-based lesion differentiation with the single-shot turbo spin-echo sequence?

    Science.gov (United States)

    Geith, Tobias; Schmidt, Gerwin; Biffar, Andreas; Dietrich, Olaf; Duerr, Hans Roland; Reiser, Maximilian; Baur-Melnyk, Andrea

    2014-09-01

    The purpose of our study was to determine the optimum combination of b values for calculating the apparent diffusion coefficient (ADC) using a diffusion-weighted (DW) single-shot turbo spin-echo (TSE) sequence in the differentiation between acute benign and malignant vertebral body fractures. Twenty-six patients with osteoporotic (mean age, 69 years; range, 31.5-86.2 years) and 20 patients with malignant vertebral fractures (mean age, 63.4 years; range, 24.7-86.4 years) were studied. T1-weighted, STIR, and T2-weighted sequences were acquired at 1.5 T. A DW single-shot TSE sequence at different b values (100, 250, 400, and 600 s/mm(2)) was applied. On the DW images for each evaluated fracture, an ROI was manually adapted to the area of hyperintense signal intensity on STIR-hypointense signal on T1-weighted images. For each ROI, nine different combinations of two, three, and four b values were used to calculate the ADC using a least-squares algorithm. The Student t test and Mann-Whitney U test were used to determine significant differences between benign and malignant fractures. An ROC analysis and the Youden index were used to determine cutoff values for assessment of the highest sensitivity and specificity for the different ADC values. The positive (PPV) and negative predictive values (NPV) were also determined. All calculated ADCs (except the combination of b = 400 s/mm(2) and b = 600 s/mm(2)) showed statistically significant differences between benign and malignant vertebral body fractures, with benign fractures having higher ADCs than malignant ones. The use of higher b values resulted in lower ADCs than those calculated with low b values. The highest AUC (0.85) showed the ADCs calculated with b = 100 and 400 s/mm(2), and the second highest AUC (0.829) showed the ADCs calculated with b = 100, 250, and 400 s/mm(2). The Youden index with equal weight given to sensitivity and specificity suggests use of an ADC calculated with b = 100, 250, and 400 s/mm(2) (cutoff

  16. An autopsied case of MM1 + MM2-cortical with thalamic-type sporadic Creutzfeldt-Jakob disease presenting with hyperintensities on diffusion-weighted MRI before clinical onset.

    Science.gov (United States)

    Iwasaki, Yasushi; Mori, Keiko; Ito, Masumi; Mimuro, Maya; Kitamoto, Tetsuyuki; Yoshida, Mari

    2017-02-01

    A 78-year-old Japanese man presented with rapidly progressive dementia and gait disturbances. Eight months before the onset of clinical symptoms, diffusion-weighted magnetic resonance imaging (DWI) demonstrated hyperintensities in the right temporal, right parietal and left medial occipital cortices. Two weeks after symptom onset, DWI showed extensive hyperintensity in the bilateral cerebral cortex, with regions of higher brightness that existed prior to symptom onset still present. Four weeks after clinical onset, periodic sharp wave complexes were identified on an electroencephalogram. Myoclonus was observed 8 weeks after clinical onset. The patient reached an akinetic mutism state and died 5 months after onset. Neuropathological examination showed widespread cerebral neocortical involvement of fine vacuole-type spongiform changes with large confluent vacuole-type spongiform changes. Spongiform degeneration with neuron loss and hypertrophic astrocytosis was also observed in the striatum and medial thalamus. The inferior olivary nucleus showed severe neuron loss with hypertrophic astrocytosis. Prion protein (PrP) immunostaining showed widespread synaptic-type PrP deposition with perivacuolar-type PrP deposition in the cerebral neocortex. Mild to moderate PrP deposition was also observed extensively in the basal ganglia, thalamus, cerebellum and brainstem, but it was not apparent in the inferior olivary nucleus. PrP gene analysis showed no mutations, and polymorphic codon 129 showed methionine homozygosity. Western blot analysis of protease-resistant PrP showed both type 1 scrapie type PrP (PrP Sc ) and type 2 PrP Sc . Based on the relationship between the neuroimaging and pathological findings, we speculated that cerebral cortical lesions with large confluent vacuoles and type 2 PrP Sc would show higher brightness and continuous hyperintensity on DWI than those with fine vacuoles and type 1 PrP Sc . We believe the present patient had a combined form of MM1

  17. Whole Body MRI at 3T with Quantitative Diffusion Weighted Imaging and Contrast-Enhanced Sequences for the Characterization of Peripheral Lesions in Patients with Neurofibromatosis Type 2 and Schwannomatosis

    International Nuclear Information System (INIS)

    Fayad, Laura M.; Blakeley, Jaishri; Plotkin, Scott; Widemann, Brigitte; Jacobs, Michael A.

    2013-01-01

    Purpose. WB-MRI is mainly used for tumor detection and surveillance. The purpose of this study is to establish the feasibility of WB-MRI at 3T for lesion characterization, with DWI/ADC-mapping and contrast-enhanced sequences, in patients with neurofibromatosis type 2 (NF-2) and schwannomatosis. Materials and Methods. At 3T, WB-MRI was performed in 11 subjects (10 NF-2 and 1 schwannomatosis) with STIR, T1, contrast-enhanced T1, and DWI/ADC mapping (b = 50, 400, 800 s/mm 2 ). Two readers reviewed imaging for the presence and character of peripheral lesions. Lesion size and features (signal intensity, heterogeneity, enhancement characteristics, and ADC values) were recorded. Descriptive statistics were reported. Results. Twenty-three lesions were identified, with average size of 4.6 ± 2.8 cm. Lesions were characterized as tumors (21/23) or cysts (2/23) by contrast-enhancement properties (enhancement in tumors, no enhancement in cysts). On T1, tumors were homogeneously isointense (5/21) or hypointense (16/21); on STIR, tumors were hyperintense and homogeneous (10/21) or heterogeneous (11/21); on postcontrast T1, tumors enhanced homogeneously (14/21) or heterogeneously (7/21); on DWI, tumor ADC values were variable (range 0.8–2.7), suggesting variability in intrinsic tumor properties. Conclusion. WB-MRI with quantitative DWI and contrast-enhanced sequences at 3T is feasible and advances the utility of WB-MRI not only to include detection, but also to provide additional metrics for lesion characterization

  18. Incidental pancreatic cysts: natural history and diagnostic accuracy of a limited serial pancreatic cyst MRI protocol

    Energy Technology Data Exchange (ETDEWEB)

    Nougaret, Stephanie; Escal, Laure; Guiu, Boris [Saint Eloi University Hospital, Department of Abdominal Imaging, Montpellier Cedex 5 (France); Reinhold, Caroline; Chong, Jaron [McGill University, Department of Abdominal Imaging, MUHC, Montreal (Canada); Mercier, Gregoire; Molinari, Nicolas [CHU Montpellier, Department of Biostatistics, Montpellier (France); Fabre, Jean Michel [CHU Montpellier, Department of Surgery, Saint Eloi University Hospital, Montpellier (France)

    2014-05-15

    To examine the natural history of incidentally detected pancreatic cysts and whether a simplified MRI protocol without gadolinium is adequate for lesion follow-up. Over a 10-year period, 301-patients with asymptomatic pancreatic cysts underwent follow-up (45 months ± 30). The magnetic resonance imaging (MRI) protocol included axial, coronal T2-weighted images, MR cholangiopancreatographic and fat suppressed T1-weighted sequences before and after gadolinium. Three radiologists independently reviewed the initial MRI, the follow-up studies using first only unenhanced images, then secondly gadolinium-enhanced-sequences. Lesion changes during follow-up were recorded and the added value of gadolinium-enhanced sequences was determined by classifying the lesions into risk categories. Three hundred and one patients (1,174 cysts) constituted the study population. Only 35/301 patients (12 %) showed significant lesion change on follow-up. Using multivariate analysis the only independent factor of lesion growth (OR = 2.4; 95 % CI, 1.7-3.3; P < 0.001) and mural nodule development (OR = 1.9; 95 % CI, 1.1-3.4, P = 0.03) during follow-up was initial lesion size. No patient with a lesion initial size less than 2 cm developed cancer during follow-up. Intra-observer agreement with and without gadolinium enhancement ranged from 0.86 to 0.97. After consensus review of discordant cases, gadolinium-enhanced sequences demonstrated no added value. Most incidental pancreatic cystic lesions did not demonstrate change during follow-up. The addition of gadolinium-enhanced-sequences had no added-value for risk assignment on serial follow-up. (orig.)

  19. Serial CT scans and MRI scans of Tay-Sachs disease

    International Nuclear Information System (INIS)

    Shimoizumi, Hideo; Miyao, Masutomo; Ichihashi, Koh; Sawa, Rituko; Yamamoto, Yoshifumi; Tanaka, Osamu; Yanagisawa, Masayoshi; Kamoshita, Shigehiko.

    1986-01-01

    Serial X-ray CT and MRI were performed on 2 cases of Tay-Sachs disease. Case 1 : a 3-year-10-month-old girl. Her developmental milestones were normal until the age of 6 months. At the age of 10 months, hypotonia and unduly sensitiveness to sounds were noticed. She had cherry red spots in both fundi, and the serum hexosaminidase A activity was low. Significant clinical features during the next 3 years included regression of developmental milestones to the level of one month, and myoclonic and generalised seizures. After 3 years she showed megalencephaly, unstable body temperature, and respiratory disorders. Case 2 : a 2-year-6-month-old boy. His developmental milestones were normal until the age of 5 months. Then he manifested hyperreaction to noises and further developments ceased. He started to deteriorate from the age of 1 year and 2 months, and had no head control at the age of 1 year and 6 months. Cherry red spots were detected and the serum hexsosaminidase A activity was low, too. X-ray CT at the early stage of cases 1 and 2 showed mild cerebral atrophy and high density areas in bilateral thalami and basal ganglia. At the late stage of Case 1, high density areas appeared in occipital and frontal white matters. MRI in both patients were strikingly similar. In their grey matters, linear light areas were demonstrated on IR images. Their white matters showed extensive dark (long T 1 ) areas on IR images, and extensive light (long T 2 ) areas on SE images. Bilateral thalami and basal ganglia were light on IR images and dark on SE images. The findings of MRI in our patients seemed to correlate well with pathological and biochemical changes in their brains. (author)

  20. Comparison of Diffusion-Weighted Imaging in the Human Brain Using Readout-Segmented EPI and PROPELLER Turbo Spin Echo With Single-Shot EPI at 7 T MRI.

    Science.gov (United States)

    Kida, Ikuhiro; Ueguchi, Takashi; Matsuoka, Yuichiro; Zhou, Kun; Stemmer, Alto; Porter, David

    2016-07-01

    The purpose of the present study was to compare periodically rotated overlapping parallel lines with enhanced reconstruction-type turbo spin echo diffusion-weighted imaging (pTSE-DWI) and readout-segmented echo planar imaging (rsEPI-DWI) with single-shot echo planar imaging (ssEPI-DWI) in a 7 T human MR system. We evaluated the signal-to-noise ratio (SNR), image distortion, and apparent diffusion coefficient values in the human brain. Six healthy volunteers were included in this study. The study protocol was approved by our institutional review board. All measurements were performed at 7 T using pTSE-DWI, rsEPI-DWI, and ssEPI-DWI sequences. The spatial resolution was 1.2 × 1.2 mm in-plane with a 3-mm slice thickness. Signal-to-noise ratio was measured using 2 scans. The ssEPI-DWI sequence showed significant image blurring, whereas pTSE-DWI and rsEPI-DWI sequences demonstrated high image quality with low geometrical distortion compared with reference T2-weighted, turbo spin echo images. Signal loss in ventral regions near the air-filled paranasal sinus/nasal cavity was found in ssEPI-DWI and rsEPI-DWI but not pTSE-DWI. The apparent diffusion coefficient values for ssEPI-DWI were 824 ± 17 × 10 and 749 ± 25 × 10 mm/s in the gray matter and white matter, respectively; the values obtained for pTSE-DWI were 798 ± 21 × 10 and 865 ± 40 × 10 mm/s; and the values obtained for rsEPI-DWI were 730 ± 12 × 10 and 722 ± 25 × 10 mm/s. The pTSE-DWI images showed no additional distortion comparison to the T2-weighted images, but had a lower SNR than ssEPI-DWI and rsEPI-DWI. The rsEPI-DWI sequence provided high-quality images with minor distortion and a similar SNR to ssEPI-DWI. Our results suggest that the benefits of the rsEPI-DWI and pTSE-DWI sequences, in terms of SNR, image quality, and image distortion, appear to outweigh those of ssEPI-DWI. Thus, pTSE-DWI and rsEPI-DWI at 7 T have great potential use for clinical diagnoses. However, it is noteworthy that both

  1. 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

  2. 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...

  3. 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.)

  4. 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.)

  5. 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.

  6. 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

  7. 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.

  8. A comparison of serial MRI with X-ray CT in a patient with Reye-like syndrome

    International Nuclear Information System (INIS)

    Fujii, Yasushi; Kuriyama, Masanori; Yoshimoto, Masahiro; Konishi, Yukuo; Fujisawa, Shinichi; Sudo, Masakatsu; Hayakawa, Katsumi

    1988-01-01

    Serial MRI and X-ray CT scans were performed on a one-year 7-month old girl with Reye-like syndrome. X-ray CT scan revealed marked hemispheric brain edema in the acute stage and moderate ventricular dilatation with diffuse low density area and cortical atrophy in the chronic stage. MRI performed in the chronic stage showed marked progressive changes. Linear high intensity areas were demonstrated on T 2 weighted MRI performed 21 days after the onset. These high intensity areas increased gradually and 60 days after the onset these high intensity areas spread to the grey matter. These high intensity changes seemed to be correspond to cortical necrosis, and those in the white matter to gliosis or degeneration of myelin. (author)

  9. 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...

  10. Asymmetric cortical high signal on diffusion weighted-MRI in a case of Creutzfeldt-Jakob disease Hipersinal cortical assimétrico na ressonância magnética na imagem em difusão em caso de doença de Creutzfeldt-Jakob

    Directory of Open Access Journals (Sweden)

    Ricardo Nitrini

    2005-06-01

    Full Text Available High signal in the cerebral cortex and/or basal ganglia on diffusion-weighted magnetic resonance imaging (DW-MRI has been described as a good diagnostic marker for sporadic Creutzfeldt-Jakob disease (sCJD. We report a case of sCJD with atypical clinical evolution and unusual DW-MRI findings. A 53-year-old man was seen with a 2-year history of a rapidly progressive dementia and cerebellar ataxia. Cerebrospinal fluid analysis, including the test for 14-3-3 protein, was normal. EEG did not show periodic activity. However, DW-MRI showed gyriform hyperintensity involving practically the entire cortical ribbon of the left hemisphere, whilst being limited to the posterior cingulate gyrus in the right hemisphere. DNA analysis showed no mutations or insertions in the prion protein gene, and homozigozity for methionine in codon 129. A subsequent brain biopsy confirmed the diagnosis of CJD. Thus, high signal on DW-MRI may be limited to the cerebral cortex and may present a very asymmetric distribution in sCJD.Hipersinal no cortex cerebral e/ou nos gânglios da base observado com a técnica de difusão da ressonância magnética (RM-DIF tem sido descrito como bom marcador diagnóstico da doença de Creutzfeldt-Jakob esporádica (DCJe. Relatamos caso de DCJe com evolução clínica atípica e achados incomuns na RM-DIF. Homem de 53 anos foi examinado com história de dois anos de demência rapidamente progressiva e ataxia cerebelar. Exame do líquido cefalorraqueano, incluindo pesquisa da proteína 14-3-3, foi normal; EEG não revelou atividade periódica; RM-DIF mostrou hiperintensidade nos giros que afetava quase inteiramente o manto cortical do hemisfério cerebral esquerdo e que no hemisfério direito se limitava à parte posterior do giro cíngulo. Análise do DNA revelou ausência de mutação ou de inserção no gene da proteína priônica e a presença de homozigose para metionina no códon 129. Biópsia cerebral confirmou o diagnóstico de DCJ

  11. 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)

  12. 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.)

  13. 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)

  14. 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.)

  15. 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.)

  16. Early Changes in Apparent Diffusion Coefficient From Diffusion-Weighted MR Imaging During Radiotherapy for Prostate Cancer

    International Nuclear Information System (INIS)

    Park, Sung Yoon; Kim, Chan Kyo; Park, Byung Kwan; Park, Won; Park, Hee Chul; Han, Deok Hyun; Kim, Bohyun

    2012-01-01

    Purpose: To investigate the feasibility of diffusion-weighted MRI (DWI) as an early and reproducible change indicator in patients receiving radiotherapy for prostate cancer (PC). Methods and Materials: Eight consecutive patients with biopsy-proven PC underwent DWI at 3T. All patients who received external-beam radiotherapy had four serial MR scans, as follows: before therapy (PreTx); after 1 week of therapy (PostT1); after 3 weeks of therapy (PostT2); and 1 month after the completion of therapy (PostT3). At each time, the apparent diffusion coefficient (ADC) was measured in tumors and normal tissues. For reproducibility of the ADC measurement, five patients also had two separate pretreatment DWI scans at an interval of −3 mm 2 /s in sequence, respectively. Compared with PreTx, PostT1 (p = 0.005), PostT2 (p = 0.003), and PostT3 (p −3 mm 2 /s in sequence, respectively. Reproducibility of ADC measurements was confirmed with a mean difference in ADC of –0.04 in peripheral zone and –0.017 in transition zone between two separate pretreatment MR scans. The mean PSA levels from PreTx to PostT3 were 9.05, 9.18, 9.25, and 4.11 ng/mL in sequence, respectively. Conclusions: DWI, as a reproducible biomarker, has the potential to evaluate the early therapeutic changes of PC to radiotherapy.

  17. Differentiation of thyroid nodules using diffusion-weighted MRI

    African Journals Online (AJOL)

    Lamiss Mohamed Abd el Aziz

    2014-10-19

    Oct 19, 2014 ... technique for brain tumors. DWI is sensitive to changes in the microstructural organization of tissue that may affect water diffusion. It has been used to evaluate head and neck tumors.9–11 The Apparent Diffusion Coefficient (ADC) value is a quantitative parameter for distinguishing malignant tumors from ...

  18. Diagnostic value of diffusion weighted MRI and ADC in differential ...

    African Journals Online (AJOL)

    Ankara Oncology Training and Research Hospital, Department of Radiology, Ankara/Turkey. 2. ... created and ADC values were measured for 72 liver masses and normal liver tissue (control group). ... ing MR gradient strength and duration) (b=400-1000 .... (B) Fat suppressed T1 weighted image after IV contrast showing.

  19. 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.)

  20. 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.)

  1. 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.)

  2. 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.)

  3. 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.)

  4. 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.)

  5. 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.)

  6. 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.

  7. 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

  8. 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)

  9. 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.)

  10. 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

  11. 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

  12. 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

  13. Plasma exchange combined with azathioprine in multiple sclerosis using serial gadolinium-enhanced MRI to monitor disease activity: a randomized single-masked cross-over pilot study

    DEFF Research Database (Denmark)

    Sørensen, P.S.; Wanscher, B; Szpirt, W

    1996-01-01

    the whole trial, and three patients discontinued the trial, two during the run-in period of azathioprine treatment and one at the introduction of PE. The primary efficacy variables were the number of gadolinium-enhancing lesions and the occurrence of new enhancing lesions on serial MRI performed every 3...... in the two periods. Although the total MS lesion load on MRI was significantly lower (p beneficial effect of PE or encourage a subsequent large...

  14. 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.)

  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. 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.

  17. 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.

  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. 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)

  20. 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.)

  1. 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.)

  2. 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.)

  3. Investigation of the growth patterns of non-functioning pituitary macroadenomas using volumetric assessments on serial MRI investigations

    Directory of Open Access Journals (Sweden)

    Jaco Pieterse

    2016-07-01

    Full Text Available Background: Benign non-functioning pituitary macroadenomas (NFMA often cause mass effect on the optic chiasm necessitating transsphenoidal surgery to prevent blindness.However, surgery is complicated and there is a high tumour recurrence rate. Currently, very little is known about the natural (and residual post-surgical growth patterns of these NFMA. Conflicting data describe decreased growth to exponential growth over various time periods.Due to lack of information on growth dynamics of these NFMA, suitable follow-up imaging protocols have not been described to date. Objective: To determine if NFMA grow or stay quiescent over a time period using serial MRI investigations and a stereo logical method to determine tumour volume. In addition, to evaluate if NFMA adhere to a certain growth pattern or grow at random. Method: Thirteen patients with NFMA had serial MRI investigations over a 73-month period at the Universitas Academic Hospital. Six of the selected patients had undergone previous surgery, while seven patients had received no medical or surgical intervention. By using astereological method, tumour volumes were calculated and plotted over time to demonstrate growth curves. The data were then fitted to tumour growth models already described in literature in order to obtain the best fit by calculating the r2 value. Results: Positive tumour growth was demonstrated in all cases. Tumour growth patterns of nine patients best fitted the exponential growth curve while the growth patterns of three patients best fitted the logistic growth curve. The remaining patient demonstrated a linear growth pattern. Conclusion: A specific growth model best described tumour growth observed in non-surgical and surgical cases. If follow-up imaging confirms positive growth, future growth can be predicted by extrapolation. This information can then be used to determine the relevant follow-up-imaging interval in each individual patient.

  4. 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

  5. Automated segmentation of ventricles from serial brain MRI for the quantification of volumetric changes associated with communicating hydrocephalus in patients with brain tumor

    Science.gov (United States)

    Pura, John A.; Hamilton, Allison M.; Vargish, Geoffrey A.; Butman, John A.; Linguraru, Marius George

    2011-03-01

    Accurate ventricle volume estimates could improve the understanding and diagnosis of postoperative communicating hydrocephalus. For this category of patients, associated changes in ventricle volume can be difficult to identify, particularly over short time intervals. We present an automated segmentation algorithm that evaluates ventricle size from serial brain MRI examination. The technique combines serial T1- weighted images to increase SNR and segments the means image to generate a ventricle template. After pre-processing, the segmentation is initiated by a fuzzy c-means clustering algorithm to find the seeds used in a combination of fast marching methods and geodesic active contours. Finally, the ventricle template is propagated onto the serial data via non-linear registration. Serial volume estimates were obtained in an automated robust and accurate manner from difficult data.

  6. Serial MRI of vestibular schwannoma presenting transient enlargement associated with intratumoral hemorrhage following radiosurgery. Two case reports

    International Nuclear Information System (INIS)

    Kikuchi, Yasuhiro; Watanabe, Kazuo; Goto, Hiromi; Isaki, Kenji; Sato, Sonomi

    2010-01-01

    Two cases of vestibular schwannoma showing transient enlargement with hemorrhage that was recognized on T2 or T2*-weighted MR image are reported. Case 1: A 72-year-old woman had a recurrent cystic lesion after resection and stereotactic radiosurgery (SRS). After retreatment by gamma knife radiosurgery, the cystic component further expanded with a fluid-fluid level, and T2 or T2*-weighted image showed markedly-low signal in the parenchymal component. Chronic hemorrhage from the cyst wall injured by irradiation is probably related to expansion of the cyst. Case 2: A 59-year-old woman received SRS. Serial MRI scans demonstrated a lesion continually expanding with homogeneous contrast enhancement on T1-weighted images. At 64 months after treatment, a central portion with high blood flow surrounded by a markedly-low intensity component of apparent hemorrhage on T2*-weighted MRI was identified. The lesion decreased in size after 73 months. Hemorrhage might occur from the neogenetic angioma-like tissue induced by irradiation effect in the tumor. Based on these observations, microvasculopathy associated with irradiation is a probable mechanism that induces bleeding in vestibular schwannoma following radiosurgery. (author)

  7. Comparing three-dimensional serial optical coherence tomography histology to MRI imaging in the entire mouse brain

    Science.gov (United States)

    Castonguay, Alexandre; Lefebvre, Joël; Pouliot, Philippe; Lesage, Frédéric

    2018-01-01

    An automated serial histology setup combining optical coherence tomography (OCT) imaging with vibratome sectioning was used to image eight wild type mouse brains. The datasets resulted in thousands of volumetric tiles resolved at a voxel size of (4.9×4.9×6.5) μm3 stitched back together to give a three-dimensional map of the brain from which a template OCT brain was obtained. To assess deformation caused by tissue sectioning, reconstruction algorithms, and fixation, OCT datasets were compared to both in vivo and ex vivo magnetic resonance imaging (MRI) imaging. The OCT brain template yielded a highly detailed map of the brain structure, with a high contrast in white matter fiber bundles and was highly resemblant to the in vivo MRI template. Brain labeling using the Allen brain framework showed little variation in regional brain volume among imaging modalities with no statistical differences. The high correspondence between the OCT template brain and its in vivo counterpart demonstrates the potential of whole brain histology to validate in vivo imaging.

  8. Serial brain MRI findings in CNS involvement of familial erythrophagocytic lymphohistiocytosis: a case report

    International Nuclear Information System (INIS)

    Cho, Kyung Soo; Yoo, Jeong Hyun; Suh, Jeong Soo; Ryu, Kyung Ha; Hong, Ki Sook; Kim, Hak Jin

    2002-01-01

    Familial erythrophagocytic lymphohistiocytosis is a fatal early childhood disorder characterized by multiorgan lymphohistiocytic infiltration and active hemophagocytosis. Involvement of the central nervous system (CNS) is not uncommon and is characterized by rapidly progressive tissue damage affecting both the gray and white matter. We encountered a case of familial erythrophagocytic lymphohistiocytosis with CNS involvement. Initial T2-weighted MRI of the brain demonstrated high signal intensity in the right thalamus, though after chemotherapy, which led to the relief of neurologic symptoms, this disappeared. After four months. however, the patient's neurologic symptoms recurred, and follow-up T2-weighted MR images showed high signal intensity in the thalami, basal ganglia, and cerebral and cerebellar white matter. Brain MRI is a useful imaging modality for the evaluation of CNS involvement and monitoring the response to treatment

  9. 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.)

  10. 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

  11. 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.

  12. 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.

  13. 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. 

  14. 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.)

  15. 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.)

  16. 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.)

  17. 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)

  18. 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)

  19. 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

  20. Acute necrotizing encephalopathy secondary to diphtheria, tetanus toxoid and whole-cell pertussis vaccination: diffusion-weighted imaging and proton MR spectroscopy findings

    International Nuclear Information System (INIS)

    Aydin, Hale; Ozgul, Esra; Agildere, Ahmet Muhtesem

    2010-01-01

    We present a previously healthy 6-month-old boy who was admitted to our hospital with lethargy, hypotonia and focal clonic seizures 6 days following diptheria, tetanus toxoid and whole-cell pertussis vaccination. A diagnosis of acute necrotising encephalopathy was made with the aid of MRI, including diffusion-weighted imaging and proton MR spectroscopy. (orig.)

  1. Acute necrotizing encephalopathy secondary to diphtheria, tetanus toxoid and whole-cell pertussis vaccination: diffusion-weighted imaging and proton MR spectroscopy findings

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Hale; Ozgul, Esra; Agildere, Ahmet Muhtesem [Baskent University Hospital, Department of Radiology, Ankara (Turkey)

    2010-07-15

    We present a previously healthy 6-month-old boy who was admitted to our hospital with lethargy, hypotonia and focal clonic seizures 6 days following diptheria, tetanus toxoid and whole-cell pertussis vaccination. A diagnosis of acute necrotising encephalopathy was made with the aid of MRI, including diffusion-weighted imaging and proton MR spectroscopy. (orig.)

  2. 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.

  3. 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.

  4. Diffusion weighted EPI in early cerebral infarction and intracerebral hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Susumu; Cho, Keiichi; Hosaka, Sumio; Ito, Koichiro; Tajima, Natsuki; Kobayashi, Shiro [Nippon Medical School (Japan). Chiba-Hokuso Hospital; Kumazaki, Tatsuo; Takahashi, Yoshiyuki

    1997-11-01

    Fifteen cases of early cerebral infarction and 14 cases of cerebral hemorrhage underwent diffusion weighted echo planar imaging. Increased intensity area was detected only 2 in 5 cases less than 3 hours from ictus, whereas infarction was correctly diagnosed in all cases over 3 hours. Infarcted area was increased on the follow-up study in 2 cases. Hematoma showed mixed intensity in hyper acute phase, very hypo in acute, mixed in subacute and very hyper in the chronic stage. High intensity area surrounded the hematoma. (author)

  5. 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.

  6. 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

  7. 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.)

  8. 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.

  9. 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.)

  10. 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.

  11. 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)

  12. 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.

  13. 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.

  14. 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.

  15. 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)

  16. 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.)

  17. 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.)

  18. DTIPrep: Quality Control of Diffusion-Weighted Images

    Directory of Open Access Journals (Sweden)

    Ipek eOguz

    2014-01-01

    Full Text Available In the last decade, diffusion MRI (dMRI studies of the human and animal brain have been used to investigate a multitude of pathologies and drug-related effects in neuroscience research. Study after study identifies white matter (WM degeneration as a crucial biomarker for all these diseases. The tool of choice for studying WM is dMRI. However, dMRI has inherently low signal-to-noise ratio and its acquisition requires a relatively long scan time; in fact, the high loads required occasionally stress scanner hardware past the point of physical failure. As a result, many types of artifacts implicate the quality of diffusion imagery. Using these complex scans containing artifacts without quality control (QC can result in considerable error and bias in the subsequent analysis, negatively affecting the results of research studies using them. However, dMRI QC remains an under-recognized issue in the dMRI community as there are no user-friendly tools commonly available to comprehensively address the issue of dMRI QC. As a result, current dMRI studies often perform a poor job at dMRI QC.Thorough QC of diffusion MRI will reduce measurement noise and improve reproducibility, and sensitivity in neuroimaging studies; this will allow researchers to more fully exploit the power of the dMRI technique and will ultimately advance neuroscience. Therefore, in this manuscript, we present our open-source software, DTIPrep, as a unified, user friendly platform for thorough quality control of dMRI data. These include artifacts caused by eddy-currents, head motion, bed vibration and pulsation, venetian blind artifacts, as well as slice-wise and gradient-wise intensity inconsistencies. This paper summarizes a basic set of features of DTIPrep described earlier and focuses on newly added capabilities related to directional artifacts and bias analysis.

  19. DTIPrep: quality control of diffusion-weighted images.

    Science.gov (United States)

    Oguz, Ipek; Farzinfar, Mahshid; Matsui, Joy; Budin, Francois; Liu, Zhexing; Gerig, Guido; Johnson, Hans J; Styner, Martin

    2014-01-01

    In the last decade, diffusion MRI (dMRI) studies of the human and animal brain have been used to investigate a multitude of pathologies and drug-related effects in neuroscience research. Study after study identifies white matter (WM) degeneration as a crucial biomarker for all these diseases. The tool of choice for studying WM is dMRI. However, dMRI has inherently low signal-to-noise ratio and its acquisition requires a relatively long scan time; in fact, the high loads required occasionally stress scanner hardware past the point of physical failure. As a result, many types of artifacts implicate the quality of diffusion imagery. Using these complex scans containing artifacts without quality control (QC) can result in considerable error and bias in the subsequent analysis, negatively affecting the results of research studies using them. However, dMRI QC remains an under-recognized issue in the dMRI community as there are no user-friendly tools commonly available to comprehensively address the issue of dMRI QC. As a result, current dMRI studies often perform a poor job at dMRI QC. Thorough QC of dMRI will reduce measurement noise and improve reproducibility, and sensitivity in neuroimaging studies; this will allow researchers to more fully exploit the power of the dMRI technique and will ultimately advance neuroscience. Therefore, in this manuscript, we present our open-source software, DTIPrep, as a unified, user friendly platform for thorough QC of dMRI data. These include artifacts caused by eddy-currents, head motion, bed vibration and pulsation, venetian blind artifacts, as well as slice-wise and gradient-wise intensity inconsistencies. This paper summarizes a basic set of features of DTIPrep described earlier and focuses on newly added capabilities related to directional artifacts and bias analysis.

  20. 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)

  1. 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

  2. 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

  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. Multishot diffusion-weighted MR imaging features in acute trauma of spinal cord

    International Nuclear Information System (INIS)

    Zhang, Jin Song; Huan, Yi

    2014-01-01

    To analyse diffusion-weighted MRI of acute spinal cord trauma and evaluate its diagnostic value. Conventional MRI and multishot, navigator-corrected DWI were performed in 20 patients with acute spinal cord trauma using 1.5-T MR within 72 h after the onset of trauma. Twenty cases were classified into four categories according to the characteristics of DWI: (1) Oedema type: ten cases presented with variable hyperintense areas within the spinal cord. There were significant differences in the apparent diffusion coefficients (ADCs) between lesions and unaffected regions (t = -7.621, P < 0.01). ADC values of lesions were markedly lower than those of normal areas. (2) Mixed type: six cases showed heterogeneously hyperintense areas due to a mixture of haemorrhage and oedema. (3) Haemorrhage type: two cases showed lesions as marked hypointensity due to intramedullary haemorrhage. (4) Compressed type (by epidural haemorrhage): one of the two cases showed an area of mild hyperintensity in the markedly compressed cord due to epidural haematoma. Muti-shot DWI of the spinal cord can help visualise and evaluate the injured spinal cord in the early stage, especially in distinguishing the cytotoxic oedema from vasogenic oedema. It can assist in detecting intramedullary haemorrhage and may have a potential role in the evaluation of compressed spinal cord. (orig.)

  6. 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)

  7. 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.)

  8. The Processing of Somatosensory Information Shifts from an Early Parallel into a Serial Processing Mode: A Combined fMRI/MEG Study.

    Science.gov (United States)

    Klingner, Carsten M; Brodoehl, Stefan; Huonker, Ralph; Witte, Otto W

    2016-01-01

    The question regarding whether somatosensory inputs are processed in parallel or in series has not been clearly answered. Several studies that have applied dynamic causal modeling (DCM) to fMRI data have arrived at seemingly divergent conclusions. However, these divergent results could be explained by the hypothesis that the processing route of somatosensory information changes with time. Specifically, we suggest that somatosensory stimuli are processed in parallel only during the early stage, whereas the processing is later dominated by serial processing. This hypothesis was revisited in the present study based on fMRI analyses of tactile stimuli and the application of DCM to magnetoencephalographic (MEG) data collected during sustained (260 ms) tactile stimulation. Bayesian model comparisons were used to infer the processing stream. We demonstrated that the favored processing stream changes over time. We found that the neural activity elicited in the first 100 ms following somatosensory stimuli is best explained by models that support a parallel processing route, whereas a serial processing route is subsequently favored. These results suggest that the secondary somatosensory area (SII) receives information regarding a new stimulus in parallel with the primary somatosensory area (SI), whereas later processing in the SII is dominated by the preprocessed input from the SI.

  9. The Processing of Somatosensory Information shifts from an early parallel into a serial processing mode: a combined fMRI/MEG study.

    Directory of Open Access Journals (Sweden)

    Carsten Michael Klingner

    2016-12-01

    Full Text Available The question regarding whether somatosensory inputs are processed in parallel or in series has not been clearly answered. Several studies that have applied dynamic causal modeling (DCM to fMRI data have arrived at seemingly divergent conclusions. However, these divergent results could be explained by the hypothesis that the processing route of somatosensory information changes with time. Specifically, we suggest that somatosensory stimuli are processed in parallel only during the early stage, whereas the processing is later dominated by serial processing. This hypothesis was revisited in the present study based on fMRI analyses of tactile stimuli and the application of DCM to magnetoencephalographic (MEG data collected during sustained (260 ms tactile stimulation. Bayesian model comparisons were used to infer the processing stream. We demonstrated that the favored processing stream changes over time. We found that the neural activity elicited in the first 100 ms following somatosensory stimuli is best explained by models that support a parallel processing route, whereas a serial processing route is subsequently favored. These results suggest that the secondary somatosensory area (SII receives information regarding a new stimulus in parallel with the primary somatosensory area (SI, whereas later processing in the SII is dominated by the preprocessed input from the SI.

  10. 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.

  11. 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

  12. 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.

  13. 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.)

  14. 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.)

  15. 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.)

  16. 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.)

  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. Characterization of chondroid matrix-forming sarcomas: gadolinium-enhanced and diffusion weighted MR imaging

    International Nuclear Information System (INIS)

    Cheng Kebin; Zhang Jing; Qu Hui; Zhang Wei; Liang Wei; Li Xiaosong; Cheng Xiaoguang; Gong Lihua

    2010-01-01

    Objective: To study the Gadolinium-enhanced MRI and diffusion weighted imaging (DWI) characteristics of the chondroid matrix-forming sarcomas. Methods: Contrast-enhanced MRI and DWI were performed in 14 cases of chondroid matrix-forming sarcomas (10 chondrosarcomas, 4 chondroblastic osteosarcomas) and 13 cases of other types of osteosarcomas. DWI was obtained with a single-shot echo-planar imaging (EPI) sequence using a 1.5 T MR imager with two different b values of 0 and 700 s/mm 2 . The apparent diffusion coefficient (ADC) values were obtained in GE Functiontool software. The contrast-enhancement pattern was evaluated and the ADC values of chondroid matrix-forming sarcomas was compared with that of other types of osteosareoma. Independent sample t-test was performed to evaluate the difference of ADC values between the group of chondroid matrix-forming sarcoma and the group of other types of osteosarcoma. In addition, nonparametric test was used to assess the difference of ADC values between the chondrosarcoma and the chondroblastic osteosarcoma. P value less than 0.05 was considered to represent a statistical significance. Results: For 14 cases of chondroid matrix-forming sarcomas, peripheral enhancement was found in all cases, septonodular enhancement was identified in 12 cases. While 13 cases of other types of osteosarcomas demonstrated heterogeneous enhancement. The mean ADC value of chondroid matrix-forming sarcomas [(2.56±0.35) x 10 -3 mm 2 /s] was significantly higher than that of other types of osteosarcoma [(1.16 ± 0.20) x 10 -3 mm 2 /s] (t=12.704, P<0.01). There was no significant difference in the ADC value between the chondrosarcoma and the chondroblastic osteosarcoma (Z=0.507, P=0.959). Conclusion: Contrast-enhanced MRI and DWI can improve differentiation between chondroid matrix-forming sarcomas and other types of osteosarcomas. (authors)

  20. Evaluation of renal allograft function early after transplantation with diffusion-weighted MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Eisenberger, Ute; Frey, Felix J. [University Hospital of Bern, Department of Nephrology and Hypertension, Bern (Switzerland); Thoeny, Harriet C. [University Hospital of Bern, Department of Radiology, Neuroradiology and Nuclear Medicine, Bern (Switzerland); Binser, Tobias; Boesch, Chris [University Hospital of Bern, Department of Clinical Research, Bern (Switzerland); Gugger, Mathias [University Hospital of Bern, Department of Pathology, Bern (Switzerland); Vermathen, Peter [University Hospital of Bern, Department of Clinical Research, Bern (Switzerland); University Bern, Department of Clinical Research/AMSM, Pavillon 52, Inselspital, P.O. Box 35, Bern (Switzerland)

    2010-06-15

    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{sub T}) was determined, which includes diffusion and micro-circulation contributions. Furthermore, diffusion and micro-circulation contributions were separated, yielding the ''perfusion fraction'' (F{sub P}), and ''perfusion-free'' diffusion (ADC{sub D}). Diffusion parameters in the ten allografts with stable function early after transplantation demonstrated low variabilities. Values for ADC{sub T} and ADC{sub D} were (x 10{sup -5} mm{sup 2}/s) 228 {+-} 14 and 203 {+-} 9, respectively, in cortex and 226 {+-} 16 and 199 {+-} 9, respectively, in medulla. F{sub P} values were 18 {+-} 5% in cortex and 19 {+-} 5% in medulla. F{sub P} values were strongly reduced to less than 12% in cortex and medulla of renal transplants with AR and ATN. F{sub 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.)

  1. Serial MRI in early Creutzfeldt-Jacob disease with a point mutation of prion protein at codon 180

    International Nuclear Information System (INIS)

    Ishida, S.; Sugino, M.; Shinoda, K.; Ohsawa, N.; Koizumi, N.; Ohta, T.; Kitamoto, T.; Tateishi, J.

    1995-01-01

    We report a 66-year-old woman with histologically diagnosed Creutzfeld-Jacob disease (CJD), followed with MRI from an early clinical stage. MRI demonstrated expansion of the high cortical signal on T2-weighted images, which differs from previous MRI reports of CJD. This patient followed an atypical clinical course: 16 months had passed before she developed akinetic mutism, and periodic sharp waves had not been detected on EEG after 2 years in spite of her akinetic mutism. Brain biopsy showed primary spongiform changes in the grey matter, and a point mutation of the prion protein gene at codon 180 was discovered using polymerase chain reaction direct sequencing and Tth 111 I cutting. This is the first case with the point mutation of the codon 180 variant with an atypical clinical course and characteristic MRI findings. (orig.)

  2. Value of diffusion-weighted imaging in predicting parametrial invasion in stage IA2-IIA cervical cancer

    International Nuclear Information System (INIS)

    Park, Jung Jae; Kim, Chan Kyo; Park, Sung Yoon; Park, Byung Kwan; Kim, Bohyun

    2014-01-01

    To investigate the value of diffusion-weighted imaging (DWI) in evaluating parametrial invasion (PMI) in stage IA2-IIA cervical cancer. A total of 117 patients with stage IA2-IIA cervical cancer who underwent preoperative MRI and radical hysterectomy were included in this study. Preoperative clinical variables and MRI variables were analysed and compared between the groups with and without pathologically proven PMI. All variables except age were significantly different between patients with and without pathologic PMI (P < 0.05). All variables except squamous cell carcinoma (SCC) antigen were also significantly correlated with pathologic PMI on univariate analysis (P < 0.05). Multivariate analysis indicated that PMI on MRI (P < 0.001) and tumour apparent diffusion coefficient (ADC) (P = 0.029) were independent predictors of pathologic PMI. Area under the curve of PMI on MRI increased significantly from 0.793 to 0.872 when combined with tumour ADC (P = 0.002). When PMI on MRI was further stratified by tumour ADC, the false negative rate was 2.0 % (1/49). In stage IA2-IIA cervical cancer, tumour ADC and PMI on MRI seem to be independent predictors of pathologic PMI. Combining the two predictors improved the diagnostic performance of identifying patients at low risk of pathologic PMI. (orig.)

  3. 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)

  4. 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

  5. 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

  6. Characteristic signal changes in the pontine base on T2- and multishot diffusion-weighted images in spinocerebellar ataxia type 1

    International Nuclear Information System (INIS)

    Adachi, M.; Kawanami, T.; Ohshima, H.; Hosoya, T.

    2006-01-01

    The aim of the present study was to demonstrate characteristic signal changes of the pontine base on T2-weighted images of patients with SCA 1, and to elucidate the relationship between abnormal high-intensities of the pontine base on T2-weighted images and the findings on multishot diffusion-weighted images. We assessed abnormal signals of the pontine base on T2-weighted images from 50 controls and six patients with SCA 1 diagnosed by genetic analysis. At the same time, we evaluated the degeneration of the transverse pontine fibers in the pontine base by multishot diffusion-weighted imaging. A midline high-intensity was seen in the pontine base on T2-weighted images in two of the 50 controls and five of the six patients with SCA 1. The midline high-intensity had a sensitivity of 83.3% for patients and a specificity of 96.0% for controls. Multishot diffusion-weighted imaging demonstrated the degeneration - the amorphous-pattern signal - of the transverse pontine fibers in four (66.7%) of the six patients. In the other two patients, the zebra-pattern signal was seen in the pontine base. The midline high-intensity on T2-weighted images appears to be one of characteristic MRI findings of SCA 1. Multishot diffusion-weighted imaging suggested that the midline high-intensity should reflect the degeneration of the transverse pontine fibers. (orig.)

  7. 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)

  8. 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.

  9. 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)

  10. 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