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Sample records for susceptibility contrast-enhanced perfusion

  1. Application of dynamic susceptibility contrast-enhanced perfusion in temporal lobe epilepsy

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    Xing, Wu; Wang, Xiaoyi; Xie, Fangfang; Liao, Weihua [Dept. of Radiology, Xiangya Hospital of Central South Univ., Changsha (China)], e-mail: doctoring@sina.com

    2013-02-15

    Background: Accurately locatithe epileptogenic focus in temporal lobe epilepsy (TLE) is important in clinical practice. Single-photon emission computed tomography (SPECT) and positron-emission tomography (PET) have been widely used in the lateralization of TLE, but both have limitations. Magnetic resonance perfusion imaging can accurately and reliably reflect differences in cerebral blood flow and volume. Purpose: To investigate the diagnostic value of dynamic susceptibility contrast-enhanced (DSC) perfusion magnetic resonance imaging (MRI) in the lateralization of the epileptogenic focus in TLE. Material and Methods: Conventional MRI and DSC-MRI scanning was performed in 20 interictal cases of TLE and 20 healthy volunteers. The relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) of the bilateral mesial temporal lobes of the TLE cases and healthy control groups were calculated. The differences in the perfusion asymmetry indices (AIs), derived from the rCBV and rCBF of the bilateral mesial temporal lobes, were pared between the two groups. Results: In the control group, there were no statistically significant differences between the left and right sides in terms of rCBV (left 1.55 {+-} 0.32, right 1.57 {+-} 0.28) or rCBF (left 99.00 {+-} 24.61, right 100.38 {+-} 23.46) of the bilateral mesial temporal lobes. However, in the case group the ipsilateral rCBV and rCBF values (1.75 {+-} 0.64 and 96.35 {+-} 22.63, respectively) were markedly lower than those of the contralateral side (2.01 {+-} 0.79 and 108.56 {+-} 26.92; P < 0.05). Both the AI of the rCBV (AIrCBV; 13.03 {+-} 10.33) and the AI of the rCBF (AIrCBF; 11.24 {+-} 8.70) of the case group were significantly higher than that of the control group (AIrCBV 5.55 {+-} 3.74, AIrCBF 5.12 {+-} 3.48; P < 0.05). The epileptogenic foci of nine patients were correctly lateralized using the 95th percentile of the AIrCBV and AIrCBF of the control group as the normal upper limits. Conclusion: In

  2. Application of dynamic susceptibility contrast-enhanced perfusion in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Xing, Wu; Wang, Xiaoyi; Xie, Fangfang; Liao, Weihua

    2013-01-01

    Background: Accurately locatithe epileptogenic focus in temporal lobe epilepsy (TLE) is important in clinical practice. Single-photon emission computed tomography (SPECT) and positron-emission tomography (PET) have been widely used in the lateralization of TLE, but both have limitations. Magnetic resonance perfusion imaging can accurately and reliably reflect differences in cerebral blood flow and volume. Purpose: To investigate the diagnostic value of dynamic susceptibility contrast-enhanced (DSC) perfusion magnetic resonance imaging (MRI) in the lateralization of the epileptogenic focus in TLE. Material and Methods: Conventional MRI and DSC-MRI scanning was performed in 20 interictal cases of TLE and 20 healthy volunteers. The relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) of the bilateral mesial temporal lobes of the TLE cases and healthy control groups were calculated. The differences in the perfusion asymmetry indices (AIs), derived from the rCBV and rCBF of the bilateral mesial temporal lobes, were pared between the two groups. Results: In the control group, there were no statistically significant differences between the left and right sides in terms of rCBV (left 1.55 ± 0.32, right 1.57 ± 0.28) or rCBF (left 99.00 ± 24.61, right 100.38 ± 23.46) of the bilateral mesial temporal lobes. However, in the case group the ipsilateral rCBV and rCBF values (1.75 ± 0.64 and 96.35 ± 22.63, respectively) were markedly lower than those of the contralateral side (2.01 ± 0.79 and 108.56 ± 26.92; P < 0.05). Both the AI of the rCBV (AIrCBV; 13.03 ± 10.33) and the AI of the rCBF (AIrCBF; 11.24 ± 8.70) of the case group were significantly higher than that of the control group (AIrCBV 5.55 ± 3.74, AIrCBF 5.12 ± 3.48; P < 0.05). The epileptogenic foci of nine patients were correctly lateralized using the 95th percentile of the AIrCBV and AIrCBF of the control group as the normal upper limits. Conclusion: In patients with TLE interictal

  3. Association of dynamic susceptibility contrast enhanced MR Perfusion parameters with prognosis in elderly patients with glioblastomas

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    Jabehdar Maralani, Pejman [University of Toronto, Department of Medical Imaging, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Melhem, Elias R.; Herskovits, Edward H. [University of Maryland Medical Center, Department of Radiology, Baltimore, MD (United States); Wang, Sumei; Voluck, Matthew R.; Learned, Kim O.; Mohan, Suyash [Perelman School of Medicine at University of Pennsylvania, Department of Radiology, Division of Neuroradiology, Philadelphia, PA (United States); Kim, Sang Joon [University of Ulsan Asan Medical Center, Department of Radiology, Songpa-gu, Seoul (Korea, Republic of); O' Rourke, Donald M. [Perelman School of Medicine at University of Pennsylvania, Department of Surgery, Division of Neurosurgery, Philadelphia, PA (United States)

    2015-09-15

    We aimed to evaluate the prognostic value of dynamic susceptibility contrast (DSC) MR perfusion in elderly patients with glioblastomas (GBM). Thirty five patients aged ≥65 and 35 aged <65 years old, (referred to as elderly and younger, respectively) were included in this retrospective study. The median relative cerebral volume (rCBV) from the enhancing region (rCBV{sub ER-Med}) and immediate peritumoral region (rCBV{sub IPR-Med}) and maximum rCBV from the enhancing region of the tumor (rCBV{sub ER-Max}) were compared and correlated with survival data. Analysis was repeated after rCBVs were dichotomized into high and low values and after excluding elderly patients who did not receive postoperative chemoradiation (34.3 %). Kaplan-Meyer survival curves and parametric and semi-parametric regression tests were used for analysis. All rCBV parameters were higher in elderly compared to younger patients (p < 0.05). After adjustment for age, none were independently associated with shorter survival (p > 0.05). After rCBV dichotomization into high and low values, high rCBV in elderly was independently associated with shorter survival compared to low rCBV in elderly, or any rCBV in younger patients (p < 0.05). rCBV can be an imaging biomarker to identify a subgroup of GBM patients in the elderly with worse prognosis compared to others. (orig.)

  4. Discrimination between glioma grades II and III in suspected low-grade gliomas using dynamic contrast-enhanced and dynamic susceptibility contrast perfusion MR imaging

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    Falk, Anna; Fahlström, Markus; Rostrup, Egill

    2014-01-01

    INTRODUCTION: Perfusion magnetic resonance imaging (MRI) can be used in the pre-operative assessment of brain tumours. The aim of this prospective study was to identify the perfusion parameters from dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast (DSC) perfusion imaging...... written informed consent in this review board-approved study. Regions of interests (ROIs) in tumour area were delineated on FLAIR images co-registered to DCE and DSC, respectively, in 25 patients with histopathological grade II (n = 18) and III (n = 7) gliomas. Statistical analysis of differences between...

  5. Combined value of susceptibility weighted imaging and dynamic susceptibility-weighted contrast-enhanced MR perfusion-weighted imaging in brain astrocytoma grading

    International Nuclear Information System (INIS)

    Wang Xiaochun; Zhang Hui; Qin Jiangbo; Wang Le; Wu Xiaofeng

    2012-01-01

    Objective: To assess the value of combination of susceptibility weighted imaging (SWI) and dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion-weighted magnetic resonance imaging in astrocytoma grading. Methods: SWI and DSC scans were performed in 82 patients with pathologically confirmed astrocytoma. The patient group consisted of grade Ⅱ (15), grade Ⅲ (10), and grade Ⅳ (57). The intratumoral susceptibility signal intensity (ITSS) and relative cerebral blood volume (rCBV) max were used to determine the grade of astrocytomas by Kruskal Wallis test, Welch test, Spearman correlation coefficients, Pearson correlation coefficients, and receiver operating characteristic curve (ROC)statistic methods. Results: There were no ITSS in 14 cases of low-grade astrocytomas, the degree of ITSS were grade 1 to 3 in anaplastic astrocytomas, the degree of ITSS were grade 3 in all of the glioblastomas, the degree of ITSS were significant difference in all grades (H=71.96, P<0.01). rCBV max in grade Ⅱ, grade Ⅲ and grade Ⅳ astrocytomas were 1.26 ± 0.42, 3.59 ± 2.09 and 8.34 ± 1.16 respectively, rCBV max were significant difference in all grades (F'=681.72, P<0.01). ITSS showed significant correlation with rCBV max (r=0.72, P<0.01) and tumor grades (r=0.89, P<0.01), and rCBV and tumor grades showed significant correlation (r=0.78, P<0.01). Area under the ROC curve application SWI, DSC, SWI and DSC in differentiation of the grade Ⅱ and grade Ⅲ astrocytomas were 0.99, 0.93, 1.00, differentiate grade Ⅲ from grade Ⅳ were 0.70, 0.94, 0.94, and differentiate high-grade from low-grade astrocytomas were 1.00, 0.99, 1.00. Conclusions: ITSS is helpful to determine the grade of astrocytomas. The use of SWI in combination with DSC may improve the diagnostic accuracy of astrocytoma grading. (authors)

  6. The role of dynamic susceptibility contrast-enhanced perfusion MR imaging in differentiating between infectious and neoplastic focal brain lesions: results from a cohort of 100 consecutive patients.

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    Valdeci Hélio Floriano

    Full Text Available BACKGROUND AND PURPOSE: Differentiating between infectious and neoplastic focal brain lesions that are detected by conventional structural magnetic resonance imaging (MRI may be a challenge in routine practice. Brain perfusion-weighted MRI (PWI may be employed as a complementary non-invasive tool, providing relevant data on hemodynamic parameters, such as the degree of angiogenesis of lesions. We aimed to employ dynamic susceptibility contrast-enhanced perfusion MR imaging (DSC-MRI to differentiate between infectious and neoplastic brain lesions by investigating brain microcirculation changes. MATERIALS AND METHODS: DSC-MRI perfusion studies of one hundred consecutive patients with non-cortical neoplastic (n = 54 and infectious (n = 46 lesions were retrospectively assessed. MRI examinations were performed using a 1.5-T scanner. A preload of paramagnetic contrast agent (gadolinium was administered 30 seconds before acquisition of dynamic images, followed by a standard dose 10 seconds after starting imaging acquisitions. The relative cerebral blood volume (rCBV values were determined by calculating the regional cerebral blood volume in the solid areas of lesions, normalized to that of the contralateral normal-appearing white matter. Discriminant analyses were performed to determine the cutoff point of rCBV values that would allow the differentiation of neoplastic from infectious lesions and to assess the corresponding diagnostic performance of rCBV when using this cutoff value. RESULTS: Neoplastic lesions had higher rCBV values (4.28±2.11 than infectious lesions (0.63±0.49 (p<0.001. When using an rCBV value <1.3 as the parameter to define infectious lesions, the sensitivity of the method was 97.8% and the specificity was 92.6%, with a positive predictive value of 91.8%, a negative predictive value of 98.0%, and an accuracy of 95.0%. CONCLUSION: PWI is a useful complementary tool in distinguishing between infectious and neoplastic brain

  7. Astrocytic tumour grading: a comparative study of three-dimensional pseudocontinuous arterial spin labelling, dynamic susceptibility contrast-enhanced perfusion-weighted imaging, and diffusion-weighted imaging

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    Xiao, Hua-Feng; Chen, Zhi-Ye; Wang, Yu-Lin; Wang, Yan; Ma, Lin; Lou, Xin; Gui, Qiu-Ping; Shi, Kai-Ning; Zhou, Zhen-Yu; Zheng, Dan-Dan

    2015-01-01

    We hypothesized that three-dimensional pseudocontinuous arterial spin labelling (pCASL) may have similar efficacy in astrocytic tumour grading as dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI), and the grading accuracy may be further improved when combined with apparent diffusion coefficient (ADC) values. Forty-three patients with astrocytic tumours were studied using diffusion weighted imaging (DWI), pCASL, and DSC-PWI. Histograms of ADC and normalized tumour cerebral blood flow values (nCBF on pCASL and nrCBF on DSC-PWI) were measured and analyzed. The mean 10 % ADC value was the DWI parameter that provided the best differentiation between low-grade astrocytoma (LGA) and high-grade astrocytoma (HGA). The nCBF and nrCBF (1.810 ± 0.979 and 2.070 ± 1.048) in LGA were significantly lower than those (4.505 ± 2.270 and 5.922 ± 2.630) in HGA. For differentiation between LGA and HGA, the cutoff values of 0.764 x 10 -3 mm 2 /s for mean 10 % ADC, 2.374 for nCBF, and 3.464 for nrCBF provided the optimal accuracy (74.4 %, 86.1 %, and 88.6 %, respectively). Combining the ADC values with nCBF or nrCBF could further improve the grading accuracy to 97.7 % or 95.3 %, respectively. pCASL is an alternative to DSC-PWI for astrocytic tumour grading. The combination of DWI and contrast-free pCASL offers a valuable choice in patients with risk factors. (orig.)

  8. Astrocytic tumour grading: a comparative study of three-dimensional pseudocontinuous arterial spin labelling, dynamic susceptibility contrast-enhanced perfusion-weighted imaging, and diffusion-weighted imaging

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    Xiao, Hua-Feng [302 Hospital of Chinese People' s Liberation Army, Department of Radiology, Beijing (China); Chen, Zhi-Ye; Wang, Yu-Lin; Wang, Yan; Ma, Lin [People' s Liberation Army General Hospital, Department of Radiology, Beijing (China); Lou, Xin [People' s Liberation Army General Hospital, Department of Radiology, Beijing (China); University of California, Department of Neurology, Los Angeles, CA (United States); Gui, Qiu-Ping [People' s Liberation Army General Hospital, Department of Pathology, Beijing (China); Shi, Kai-Ning; Zhou, Zhen-Yu; Zheng, Dan-Dan [General Electric Healthcare (China) Co., Ltd., Beijing; Wang, Danny J.J. [University of California, Department of Neurology, Los Angeles, CA (United States)

    2015-12-15

    We hypothesized that three-dimensional pseudocontinuous arterial spin labelling (pCASL) may have similar efficacy in astrocytic tumour grading as dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI), and the grading accuracy may be further improved when combined with apparent diffusion coefficient (ADC) values. Forty-three patients with astrocytic tumours were studied using diffusion weighted imaging (DWI), pCASL, and DSC-PWI. Histograms of ADC and normalized tumour cerebral blood flow values (nCBF on pCASL and nrCBF on DSC-PWI) were measured and analyzed. The mean 10 % ADC value was the DWI parameter that provided the best differentiation between low-grade astrocytoma (LGA) and high-grade astrocytoma (HGA). The nCBF and nrCBF (1.810 ± 0.979 and 2.070 ± 1.048) in LGA were significantly lower than those (4.505 ± 2.270 and 5.922 ± 2.630) in HGA. For differentiation between LGA and HGA, the cutoff values of 0.764 x 10{sup -3} mm{sup 2}/s for mean 10 % ADC, 2.374 for nCBF, and 3.464 for nrCBF provided the optimal accuracy (74.4 %, 86.1 %, and 88.6 %, respectively). Combining the ADC values with nCBF or nrCBF could further improve the grading accuracy to 97.7 % or 95.3 %, respectively. pCASL is an alternative to DSC-PWI for astrocytic tumour grading. The combination of DWI and contrast-free pCASL offers a valuable choice in patients with risk factors. (orig.)

  9. Dynamic contrast enhanced MRI for perfusion quantification

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    Andersen, Irene Klærke

    2002-01-01

    Magnetic resonance imaging, during bolus passage of a paramagnetic contrast agent, is used world-wide to obtain parameters that reflect the pathological state of tissue. Abnormal perfusion occurs in diseases such as stoke and tumour. Consequently, perfusion quantication could have signi cant...... clinical value both in diagnosis and treatment of such pathologies. One approach for perfusion quanti cation involves using the contrast mechanism that a ects the transverse relaxation rates of the magnetization, R2 or R 2 , since this provides the most pronounced effect. However, the linearity between...

  10. Diagnostic examination performance by using microvascular leakage, cerebral blood volume, and blood flow derived from 3-T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in the differentiation of glioblastoma multiforme and brain metastasis

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    Server, Andres; Nakstad, Per H.; Orheim, Tone E.D.; Graff, Bjoern A.; Josefsen, Roger; Kumar, Theresa

    2011-01-01

    Conventional magnetic resonance (MR) imaging has limited capacity to differentiate between glioblastoma multiforme (GBM) and metastasis. The purposes of this study were: (1) to compare microvascular leakage (MVL), cerebral blood volume (CBV), and blood flow (CBF) in the distinction of metastasis from GBM using dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI), and (2) to estimate the diagnostic accuracy of perfusion and permeability MR imaging. A prospective study of 61 patients (40 GBMs and 21 metastases) was performed at 3 T using DSC-MRI. Normalized rCBV and rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe), and by dividing the value in the tumor by the value in the peri-enhancing region (rCBVt/e, rCBFt/e), as well as MVL were calculated. Hemodynamic and histopathologic variables were analyzed statistically and Spearman/Pearson correlations. Receiver operating characteristic curve analysis was performed for each of the variables. The rCBVe, rCBFe, and MVL were significantly greater in GBMs compared with those of metastases. The optimal cutoff value for differentiating GBM from metastasis was 0.80 which implies a sensitivity of 95%, a specificity of 92%, a positive predictive value of 86%, and a negative predictive value of 97% for rCBVe ratio. We found a modest correlation between rCBVt and rCBFt ratios. MVL measurements in GBMs are significantly higher than those in metastases. Statistically, both rCBVe, rCBVt/e and rCBFe, rCBFt/e were useful in differentiating between GBMs and metastases, supporting the hypothesis that perfusion MR imaging can detect infiltration of tumor cells in the peri-enhancing region. (orig.)

  11. Diagnostic examination performance by using microvascular leakage, cerebral blood volume, and blood flow derived from 3-T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in the differentiation of glioblastoma multiforme and brain metastasis

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    Server, Andres; Nakstad, Per H. [Oslo University Hospital-Ullevaal, Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo (Norway); University of Oslo, Oslo (Norway); Orheim, Tone E.D. [Oslo University Hospital, Interventional Centre, Oslo (Norway); Graff, Bjoern A. [Oslo University Hospital-Ullevaal, Department of Radiology and Nuclear Medicine, Oslo (Norway); Josefsen, Roger [Oslo University Hospital-Ullevaal, Department of Neurosurgery, Oslo (Norway); Kumar, Theresa [Oslo University Hospital-Ullevaal, Department of Pathology, Oslo (Norway)

    2011-05-15

    Conventional magnetic resonance (MR) imaging has limited capacity to differentiate between glioblastoma multiforme (GBM) and metastasis. The purposes of this study were: (1) to compare microvascular leakage (MVL), cerebral blood volume (CBV), and blood flow (CBF) in the distinction of metastasis from GBM using dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI), and (2) to estimate the diagnostic accuracy of perfusion and permeability MR imaging. A prospective study of 61 patients (40 GBMs and 21 metastases) was performed at 3 T using DSC-MRI. Normalized rCBV and rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe), and by dividing the value in the tumor by the value in the peri-enhancing region (rCBVt/e, rCBFt/e), as well as MVL were calculated. Hemodynamic and histopathologic variables were analyzed statistically and Spearman/Pearson correlations. Receiver operating characteristic curve analysis was performed for each of the variables. The rCBVe, rCBFe, and MVL were significantly greater in GBMs compared with those of metastases. The optimal cutoff value for differentiating GBM from metastasis was 0.80 which implies a sensitivity of 95%, a specificity of 92%, a positive predictive value of 86%, and a negative predictive value of 97% for rCBVe ratio. We found a modest correlation between rCBVt and rCBFt ratios. MVL measurements in GBMs are significantly higher than those in metastases. Statistically, both rCBVe, rCBVt/e and rCBFe, rCBFt/e were useful in differentiating between GBMs and metastases, supporting the hypothesis that perfusion MR imaging can detect infiltration of tumor cells in the peri-enhancing region. (orig.)

  12. Measurement of perfusion using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI in neurooncology. Physical basics and clinical applications; Perfusionsmessung mit der T2*-Kontrastmitteldynamik in der Neuroonkologie. Physikalische Grundlagen und klinische Anwendungen

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    Weber, M.-A.; Giesel, F.L.; Kauczor, H.-U.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg (Germany). Abteilung Radiologie; Risse, F.; Schad, L.R. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg (Germany). Abteilung Medizinische Physik in der Radiologie

    2005-07-01

    Perfusion imaging in the central nervous system (CNS) is mostly performed using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI. The first-pass of a contrast bolus in brain tissue is monitored by a series of T2*-weighted MR images. The susceptibility effect of the paramagnetic contrast agent leads to a signal loss that can be converted, using the principles of the indicator dilution theory, into an increase of the contrast agent concentration. From these data, parameter maps of cerebral blood volume (CBV) and flow (CBF) can be derived. Regional CBF and CBV values can be obtained by region-of-interest analysis. This review article describes physical basics of DSC MRI and summarizes the literature of DSC MRI in neurooncological issues. Studies, all with relatively limited patient numbers, report that DSC MRI is useful in the preoperative diagnosis of gliomas, CNS-lymphomas, and solitary metastases, as well as in the differentiation of these neoplastic lesions from infections and tumor-like manifestations of demyelinating disease. Additionally, DSC MRI is suitable for determining glioma grade and regions of active tumor growth which should be the target of stereotactic biopsy. After therapy, DSC MRI helps better assessing the tumor response to therapy, residual tumor after therapy, and possible treatment failure and therapy-related complications, such as radiation necrosis. The preliminary results show that DSC MRI is a diagnostic tool depicting regional variations in microvasculature of normal and diseased brains. (orig.) [German] Die MRT-Perfusionsmessungen im Zentralnervensystem (ZNS) werden derzeit hauptsaechlich mit der kontrastmittelverstaerkten T2*-Dynamik durchgefuehrt, die die Passage eines schnellen Kontrastmittelbolus mit einer Serie von T2*-gewichteten MRT-Aufnahmen verfolgt und charakterisiert. Dabei wird der Signalabfall, bedingt durch den Suszeptibilitaetseffekt des paramagnetischen Kontrastmittels, mittels geeigneter

  13. Differentiation of grade II/III and grade IV glioma by combining ''T1 contrast-enhanced brain perfusion imaging'' and susceptibility-weighted quantitative imaging

    International Nuclear Information System (INIS)

    Saini, Jitender; Gupta, Pradeep Kumar; Gupta, Rakesh Kumar; Sahoo, Prativa; Singh, Anup; Patir, Rana; Ahlawat, Suneeta; Beniwal, Manish; Thennarasu, K.; Santosh, Vani

    2018-01-01

    MRI is a useful method for discriminating low- and high-grade glioma using perfusion MRI and susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of T1-perfusion MRI and SWI in discriminating among grade II, III, and IV gliomas. T1-perfusion MRI was used to measure relative cerebral blood volume (rCBV) in 129 patients with glioma (70 grade IV, 33 grade III, and 26 grade II tumors). SWI was also used to measure the intratumoral susceptibility signal intensity (ITSS) scores for each tumor in these patients. rCBV and ITSS values were compared to seek differences between grade II vs. grade III, grade III vs. grade IV, and grade III+II vs. grade IV tumors. Significant differences in rCBV values of the three grades of the tumors were noted and pairwise comparisons showed significantly higher rCBV values in grade IV tumors as compared to grade III tumors, and similarly increased rCBV was seen in the grade III tumors as compared to grade II tumors (p < 0.001). Grade IV gliomas showed significantly higher ITSS scores on SWI as compared to grade III tumors (p < 0.001) whereas insignificant difference was seen on comparing ITSS scores of grade III with grade II tumors. Combining the rCBV and ITSS resulted in significant improvement in the discrimination of grade III from grade IV tumors. The combination of rCBV values derived from T1-perfusion MRI and SWI derived ITSS scores improves the diagnostic accuracy for discrimination of grade III from grade IV gliomas. (orig.)

  14. Differentiation of grade II/III and grade IV glioma by combining ''T1 contrast-enhanced brain perfusion imaging'' and susceptibility-weighted quantitative imaging

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    Saini, Jitender [National Institute of Mental Health and Neurosciences, Neuroimaging and Interventional Radiology, Bangalore (India); Gupta, Pradeep Kumar; Gupta, Rakesh Kumar [Fortis Memorial Research Institute, Department of Radiology and Imaging, Gurugram (India); Sahoo, Prativa [Philips Health System, Philips India Limited, Bangalore (India); Beckman Research Institute, Mathematical Oncology, Duarte, CA (United States); Singh, Anup [Indian Institute of Technology Delhi, Center for Biomedical Engineering, Delhi (India); Patir, Rana [Fortis Memorial Research Institute, Department of Neurosurgery, Gurugram (India); Ahlawat, Suneeta [Fortis Memorial Research Institute, SRL Diagnostics, Gurugram (India); Beniwal, Manish [National Institute of Mental Health and Neurosciences, Department of Neurosurgery, Bangalore (India); Thennarasu, K. [National Institute of Mental Health and Neurosciences, Department of Biostatistics, Bangalore (India); Santosh, Vani [National Institute of Mental Health and Neurosciences, Department of Neuropathology, Bangalore (India)

    2018-01-15

    MRI is a useful method for discriminating low- and high-grade glioma using perfusion MRI and susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of T1-perfusion MRI and SWI in discriminating among grade II, III, and IV gliomas. T1-perfusion MRI was used to measure relative cerebral blood volume (rCBV) in 129 patients with glioma (70 grade IV, 33 grade III, and 26 grade II tumors). SWI was also used to measure the intratumoral susceptibility signal intensity (ITSS) scores for each tumor in these patients. rCBV and ITSS values were compared to seek differences between grade II vs. grade III, grade III vs. grade IV, and grade III+II vs. grade IV tumors. Significant differences in rCBV values of the three grades of the tumors were noted and pairwise comparisons showed significantly higher rCBV values in grade IV tumors as compared to grade III tumors, and similarly increased rCBV was seen in the grade III tumors as compared to grade II tumors (p < 0.001). Grade IV gliomas showed significantly higher ITSS scores on SWI as compared to grade III tumors (p < 0.001) whereas insignificant difference was seen on comparing ITSS scores of grade III with grade II tumors. Combining the rCBV and ITSS resulted in significant improvement in the discrimination of grade III from grade IV tumors. The combination of rCBV values derived from T1-perfusion MRI and SWI derived ITSS scores improves the diagnostic accuracy for discrimination of grade III from grade IV gliomas. (orig.)

  15. Hepatic blood perfusion estimated by dynamic contrast-enhanced computed tomography in pigs

    DEFF Research Database (Denmark)

    Winterdahl, Michael; Sørensen, Michael; Keiding, Inger Susanne

    2012-01-01

    The aim of this study was to determine whether dynamic contrast-enhanced computed tomography (DCE-CT) and the slope method can provide absolute measures of hepatic blood perfusion from the hepatic artery (HA) and portal vein (PV) at experimentally varied blood flow rates.......The aim of this study was to determine whether dynamic contrast-enhanced computed tomography (DCE-CT) and the slope method can provide absolute measures of hepatic blood perfusion from the hepatic artery (HA) and portal vein (PV) at experimentally varied blood flow rates....

  16. Facing Contrast-Enhancing Gliomas: Perfusion MRI in Grade III and Grade IV Gliomas according to Tumor Area

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    Anna Luisa Di Stefano

    2014-01-01

    Full Text Available Tumoral neoangiogenesis characterizes high grade gliomas. Relative Cerebral Blood Volume (rCBV, calculated with Dynamic Susceptibility Contrast (DSC Perfusion-Weighted Imaging (PWI, allows for the estimation of vascular density over the tumor bed. The aim of the study was to characterize putative tumoral neoangiogenesis via the study of maximal rCBV with a Region of Interest (ROI approach in three tumor areas—the contrast-enhancing area, the nonenhancing tumor, and the high perfusion area on CBV map—in patients affected by contrast-enhancing glioma (grades III and IV. Twenty-one patients were included: 15 were affected by grade IV and 6 by grade III glioma. Maximal rCBV values for each patient were averaged according to glioma grade. Although rCBV from contrast-enhancement and from nonenhancing tumor areas was higher in grade IV glioma than in grade III (5.58 and 2.68; 3.01 and 2.2, resp., the differences were not significant. Instead, rCBV recorded in the high perfusion area on CBV map, independently of tumor compartment, was significantly higher in grade IV glioma than in grade III (7.51 versus 3.78, P=0.036. In conclusion, neoangiogenesis encompasses different tumor compartments and CBV maps appear capable of best characterizing the degree of neovascularization. Facing contrast-enhancing brain tumors, areas of high perfusion on CBV maps should be considered as the reference areas to be targeted for glioma grading.

  17. Contrast-enhanced 3D MRI of lung perfusion in children with cystic fibrosis - initial results

    International Nuclear Information System (INIS)

    Eichinger, Monika; Puderbach, Michael; Zuna, Ivan; Kauczor, Hans-Ulrich; Fink, Christian; Gahr, Julie; Mueller, Frank-Michael; Ley, Sebastian; Plathow, Christian; Tuengerthal, Siegfried

    2006-01-01

    This paper is a feasibility study of magnetic resonance imaging (MRI) of lung perfusion in children with cystic fibrosis (CF) using contrast-enhanced 3D MRI. Correlation assessment of perfusion changes with structural abnormalities. Eleven CF patients (9 f, 2 m; median age 16 years) were examined at 1.5 T. Morphology: HASTE coronal, transversal (TR/TE/α/ST: 600 ms/28 ms/180 /6 mm), breath-hold 18 s. Perfusion: Time-resolved 3D GRE pulse sequence (FLASH, TE/TR/α: 0.8/1.9 ms/40 ), parallel imaging (GRAPPA, PAT 2). Twenty-five data sets were acquired after intravenous injection of 0.1 mmol/kg body weight of gadodiamide, 3-5 ml/s. A total of 198 lung segments were analyzed by two radiologists in consensus and scored for morphological and perfusion changes. Statistical analysis was performed by Mantel-Haenszel chi-square test. Results showed that perfusion defects were observed in all patients and present in 80% of upper, and 39% of lower lobes. Normal lung parenchyma showed homogeneous perfusion (86%, P<0.0001). Severe morphological changes led to perfusion defects (97%, P<0.0001). Segments with moderate morphological changes showed normal (53%) or impaired perfusion (47%). In conclusion, pulmonary perfusion is easy to judge in segments with normal parenchyma or severe changes. In moderately damaged segments, MRI of lung perfusion may help to better assess actual functional impairment. Contrast-enhanced 3D MRI of lung perfusion has the potential for early vascular functional assessment and therapy control in CF patients. (orig.)

  18. Post-operative monitoring of tissue transfers: advantages using contrast enhanced ultrasound (CEUS) and contrast enhanced MRI (ceMRI) with dynamic perfusion analysis?

    Science.gov (United States)

    Lamby, P; Prantl, L; Fellner, C; Geis, S; Jung, E M

    2011-01-01

    The immediate evaluation of microvascular tissue flaps with respect to microcirculation after transplantation is crucial for optimal monitoring and outcome. The purpose of our investigation was to evaluate the clinical value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced MRI (ceMRI) for monitoring the integrity of tissue flaps in plastic surgery. To this end, we investigated 10 patients (47 ± 16 a) between postoperative day 7 and 14 who underwent flap surgery in order to cover tissue defects in various body regions. For CEUS we utilized the GE LOGIQ E9 equipped with a linear transducer (6-9 MHz). After application of 2.4 ml SonoVue, the tissue perfusion was detected in Low MI-Technique (MI present, both technologies provide an optimal assessment of perfusion in cutaneous, subcutaneous and muscle tissue layers, whereby the detection of fatty tissue perfusion is currently more easily detected using CEUS compared to ceMRI.

  19. Isoattenuating insulinomas at biphasic contrast-enhanced CT: frequency, clinicopathologic features and perfusion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang; Xue, Hua-dan; Sun, Hao; Wang, Xuan; He, Yong-lan; Jin, Zheng-yu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Zhao, Yu-pei [Peking Union Medical College Hospital, Department of General Surgery, Beijing (China)

    2016-10-15

    We aimed to determine the frequency of isoattenuating insulinomas, to investigate their clinicopathological features and to assess their regional pancreatic perfusion characteristics. Institutional review board approval was obtained, and patient informed consent was waived. From July 2010 to June 2014, 170 patients (66 male, 104 female) with endogenous hyperinsulinemic hypoglycemia underwent biphasic contrast-enhanced CT before surgery, and 129 of those patients also received preoperative whole-pancreas CT perfusion. A total of 181 tumours were proved histopathologically after surgery. Enhancement pattern and regional pancreatic perfusion characteristics were analyzed. Clinical features, tumour size and pathological grading were investigated. The frequency of isoattenuating tumours was 24.9 %. Tumour size and WHO grading was not significantly different between isoattenuating and hyperattenuating tumours. Tumour-free regions had identical blood flow (BF) regardless of their location (p = 0.35). Isoattenuating tumour-harbouring regions had lower BF compared with hyperattenuating tumour-harbouring regions; both showed higher BF compared with tumour-free neighbourhood regions (all p < 0.01). For patients with isoattenuating tumours, the overall hospital stay was longer (p < 0.01). A substantial subset of insulinomas were isoattenuating on biphasic CT. CT perfusion showed higher BF in tumour-harbouring regions compared to tumour-free regions, providing a clue for tumour regionalization. (orig.)

  20. Assessment of brain metastases by means of dynamic susceptibility contrast enhanced MRI

    International Nuclear Information System (INIS)

    Knopp, M.; Wenz, F.; Debus, J.; Hentrich, H.R.

    2002-01-01

    Full text: To assess if pre therapeutic measurements of regional cerebral blood flow (rCBF) and volume (rCVB) are able to predict the response of brain metastases to radiation therapy and to assess the influence of radiosurgery on rCBF and rCBV on brain metastases and normal surrounding tissue. We examined 25 patients with brain metastases prior to high dose radiosurgery with conventional T1 and T2 weighted MRI and dynamic susceptibility contrast enhanced MRI (DSC MRI). For DSC MRI 55 T2*w GE images of two sections were acquired after bolus administration of 0.1 mmol/kg gadoteridol (ProHance) for the simultaneous measurement of brain feeding arteries and brain tissue. This allowed an absolute quantification of rCBF and rCBV. Follow-up examinations were performed 6 weeks and 3 months after radiotherapy and the acquired perfusion data were related to a 3 point scale of treatment outcome. Radiosurgery was performed by a linear accelerator with a 80% isodose of 18-20 Gv. For treatment planning the heads of the patients were immobilized by a cask mask to avoid head movement. DSC MRI was able to assess perfusion data in all patients. Higher pre therapeutic rCBV seems to predict a poor treatment outcome. After radiosurgery patients with tumor remission and stable disease presented a decrease of rCBV over time regardless of temporary tumor volume increase. Patients with tumor progression at the 3 month followup presented an increase of rCBV. Effects on normal surrounding tissue could not be observed. DSC MRI using Gadoteridol allows the non-invasive assessment of rCBV and rCBF of brain metastases and its changes due to radiosurgery. The method may also be able to predict treatment outcome. Furthermore radiofrequency effects on surrounding unaffected tissue can be monitored. Copyright (2002) Blackwell Science Pty Ltd

  1. Semi-automatic motion compensation of contrast-enhanced ultrasound images from abdominal organs for perfusion analysis

    Czech Academy of Sciences Publication Activity Database

    Schafer, S.; Nylund, K.; Saevik, F.; Engjom, T.; Mézl, M.; Jiřík, Radovan; Dimcevski, G.; Gilja, O.H.; Tönnies, K.

    2015-01-01

    Roč. 63, AUG 1 (2015), s. 229-237 ISSN 0010-4825 R&D Projects: GA ČR GAP102/12/2380 Institutional support: RVO:68081731 Keywords : ultrasonography * motion analysis * motion compensation * registration * CEUS * contrast-enhanced ultrasound * perfusion * perfusion modeling Subject RIV: FS - Medical Facilities ; Equipment Impact factor: 1.521, year: 2015

  2. Arterio-venous anastomoses in mice affect perfusion measurements with dynamic contrast enhanced CT

    International Nuclear Information System (INIS)

    Gabra, Peter; Lee, Ting-Yim; Shen, Gang; Xuan, Jim

    2010-01-01

    Accurate measurement of perfusion with dynamic contrast enhanced CT requires an arterial input curve (AIC) uncontaminated by venous sources. Arterio-venous anastomoses (AVAs) are sources of contamination if contrast is injected intravenously. We seek to identify AVAs in mice and associated errors in perfusion measurements. Six transgenic mice with spontaneous prostate tumor were scanned with a micro-CT scanner (GE Healthcare (GE)) using a high resolution anatomical and a lower resolution perfusion protocol. For the anatomical protocol, a CT scan was performed during injection of an iodinated contrast agent (Hypaque) into a tail vein. Images covering the thoracic, abdominal and pelvic regions at an isotropic resolution of 175 µm were reconstructed and rendered in 3D to show the arterial and venous tree (Advantage Window, GE). For the perfusion protocol, each mouse was continuously scanned for 40 s and the contrast agent (Hypaque) was injected via a tail vein 5 s into scanning. Tumor images were reconstructed every second. Tumor blood flow (BF) and volume (BV) maps were calculated with CT perfusion software (GE) using AIC measured either from abdominal aorta (AA) or tail (caudal) artery (TA). In all mice, there was an AVA from the bifurcation of the inferior vena cava to the tail artery shunting venous blood and portion of the contrast agent injected into the tail vein into the TA. Contrast arrival time at the TA preceded that at the AA by 3.3 ± 0.5 s (P < 0.05). Mean tumor BV and BF values calculated with AA versus TA were 10.0 ± 1.8 versus 4.8 ± 2.1 ml (100 g) −1 (P < 0.05) and 108.8 ± 26.5 versus 33.0 ± 8.5 ml min −1 100 g −1 (P < 0.05), respectively. AVA in the murine pelvic region can result in inaccurate and more variable measurements of pelvic organ/tissue perfusion when the tail artery is used as the AIC

  3. Evaluation of liver parenchyma and perfusion using dynamic contrast-enhanced computed tomography and contrast-enhanced ultrasonography in captive green iguanas (Iguana iguana) under general anesthesia.

    Science.gov (United States)

    Nardini, Giordano; Di Girolamo, Nicola; Leopardi, Stefania; Paganelli, Irene; Zaghini, Anna; Origgi, Francesco C; Vignoli, Massimo

    2014-05-13

    Contrast-enhanced diagnostic imaging techniques are considered useful in veterinary and human medicine to evaluate liver perfusion and focal hepatic lesions. Although hepatic diseases are a common occurrence in reptile medicine, there is no reference to the use of contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) to evaluate the liver in lizards. Therefore, the aim of this study was to evaluate the pattern of change in echogenicity and attenuation of the liver in green iguanas (Iguana iguana) after administration of specific contrast media. An increase in liver echogenicity and density was evident during CEUS and CECT, respectively. In CEUS, the mean ± SD (median; range) peak enhancement was 19.9% ± 7.5 (18.3; 11.7-34.6). Time to peak enhancement was 134.0 ± 125.1 (68.4; 59.6-364.5) seconds. During CECT, first visualization of the contrast medium was at 3.6 ± 0.5 (4; 3-4) seconds in the aorta, 10.7 ± 2.2 (10.5; 7-14) seconds in the hepatic arteries, and 15 ± 4.5 (14.5; 10-24) seconds in the liver parenchyma. Time to peak was 14.1 ± 3.4 (13; 11-21) and 31 ± 9.6 (29; 23-45) seconds in the aorta and the liver parenchyma, respectively. CEUS and dynamic CECT are practical means to determine liver hemodynamics in green iguanas. Distribution of contrast medium in iguana differed from mammals. Specific reference ranges of hepatic perfusion for diagnostic evaluation of the liver in iguanas are necessary since the use of mammalian references may lead the clinician to formulate incorrect diagnostic suspicions.

  4. Perfusion redistribution after a pulmonary-embolism-like event with contrast enhanced EIT.

    Science.gov (United States)

    Nguyen, D T; Bhaskaran, A; Chik, W; Barry, M A; Pouliopoulos, J; Kosobrodov, R; Jin, C; Oh, T I; Thiagalingam, A; McEwan, A L

    2015-06-01

    Recent studies showed that regional pulmonary perfusion can be reliably estimated using electrical impedance tomography (EIT) with the aid of hypertonic saline based contrast enhancement. Building on these successful studies, we studied contrast EIT for pulmonary perfusion defect caused by an artificially induced pulmonary embolism (PE) in a large ovine model (N = 8, 78 ± 7.8 kg). Furthermore, the efficacy of a less invasive contrast bolus of 0.77 ml kg(-1) of NaCl 3% was compared with a more concentrated bolus of 0.13 ml kg(-1) of NaCl 20%. Prior to the injection of each contrast bolus injection, ventilation was turned off to provide a total of 40 to 45 s of apnoea. Each bolus of impedance contrast was injected through a catheter into the right atrium. Pulmonary embolisation was performed by balloon occlusion of part of the right branch of the pulmonary trunk. Four parameters representing the kinetics of the contrast dilution in the lung were evaluated for statistical differences between baseline and PE, including peak value, maximum uptake, maximum washout and area under the curve of the averaged contrast dilution curve in each lung. Furthermore, the right lung to left lung (R2L) ratio of each the aforementioned parameters were assessed. While all of the R2L ratios yielded significantly different means between baseline and PE, it can be concluded that the R2L ratios of area under the curve and peak value of the averaged contrast dilution curve are the most promising and reliable in assessing PE. It was also found that the efficacy of the two types of impedance contrasts were not significantly different in distinguishing PE from baseline in our model.

  5. Interobserver Variation of the Bolus-and-Burst Method for Pancreatic Perfusion with Dynamic – Contrast-Enhanced Ultrasound

    Czech Academy of Sciences Publication Activity Database

    Stangeland, M.; Engjom, T.; Mézl, M.; Jiřík, Radovan; Gilja, O.H.; Dimcevski, G.; Nylund, K.

    2017-01-01

    Roč. 3, č. 3 (2017), E99-E106 E-ISSN 2199-7152 Institutional support: RVO:68081731 Keywords : interobserver * dynamic contrast-enhanced ultrasound * perfusion * pancreas Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Medical engineering https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0043-110475

  6. Assessment of renal perfusion with contrast-enhanced ultrasound: Preliminary results in early diabetic nephropathies.

    Science.gov (United States)

    Dong, Yi; Wang, Wen-Ping; Lin, Pan; Fan, Peili; Mao, Feng

    2016-01-01

    We performed a prospective study to evaluate the value of contrast-enhanced ultrasound (CEUS) in quantitative evaluation of renal cortex perfusion in patients suspected of early diabetic nephropathies (DN), with the estimated GFR (MDRD equation) as the gold standard. The study protocol was approved by the hospital review board; each patient gave written informed consent. Our study included 46 cases (21 males and 25 females, mean age 55.6 ± 4.14 years) of clinical confirmed early DN patients. After intravenous bolus injection of 1 ml sulfur hexafluoride microbubbles of ultrasound contrast agent, real time CEUS of renal cortex was performed successively using a 2-5 MHz convex probe. Time-intensity curves (TICs) and quantitative indexes were created with Qlab software. Receiver operating characteristic (ROC) curves were used to predict the diagnostic criteria of CEUS quantitative indexes, and their diagnostic efficiencies were compared with resistance index (RI) and peak systolic velocity (PSV) of renal segmental arteries by chi square test. Our control group included forty-five healthy volunteers. Difference was considered statistically significant with P  0.05). CEUS might be helpful to improve early diagnosis of DN by quantitative analyses. AUC and DPI might be valuable quantitative indexes.

  7. Dynamic contrast-enhanced quantitative perfusion measurement of the brain using T-1-weighted MRI at 3T

    DEFF Research Database (Denmark)

    Larsson, H.B.W.; Hansen, A.E.; Berg, H.K.

    2008-01-01

    Purpose: To develop a method for the measurement of brain perfusion based on dynamic contrast-enhanced T-1-weighted MR imaging. Materials and Methods: Dynamic imaging of the first pass of a bolus of a paramagnetic contrast agent was performed using a 3T whole-body magnet and a T-1-weighted fast...... field echo sequence. The input function was obtained from the internal carotid artery. An initial T-1 measurement was performed in order to convert the MR signal to concentration of the contrast agent. Pixelwise and region of interest (ROI)based calculation of cerebral perfusion (CBF) was performed...... inside the infarct core was, 9 mL/100g/min in one of the stroke patients. The other stroke patient had postischemic hyperperfusion and CBF was 140 mL/100g/min. Conclusion: Absolute values of brain perfusion can be obtained using dynamic contrast-enhanced MRI. These values correspond,to expected values...

  8. Renal Cell Carcinoma Perfusion before and after Radiofrequency Ablation Measured with Dynamic Contrast Enhanced MRI: A Pilot Study.

    Science.gov (United States)

    Wah, Tze Min; Sourbron, Steven; Wilson, Daniel Jonathan; Magee, Derek; Gregory, Walter Martin; Selby, Peter John; Buckley, David L

    2018-01-08

    To investigate if the early treatment effects of radiofrequency ablation (RFA) on renal cell carcinoma (RCC) can be detected with dynamic contrast enhanced (DCE)-MRI and to correlate RCC perfusion with RFA treatment time. 20 patients undergoing RFA of their 21 RCCs were evaluated with DCE-MRI before and at one month after RFA treatment. Perfusion was estimated using the maximum slope technique at two independent sittings. Total RCC blood flow was correlated with total RFA treatment time, tumour location, size and histology. DCE-MRI examinations were successfully evaluated for 21 RCCs (size from 1.3 to 4 cm). Perfusion of the RCCs decreased significantly ( p measuring RCC perfusion before and after RFA. Perfusion significantly decreases in the zone of ablation, suggesting that it may be useful for the assessment of treatment efficacy. Pre-RFA RCC blood flow may be used to predict RFA treatment time.

  9. Perfusion magnetic resonance imaging and magnetic resonance spectroscopy of cerebral gliomas showing imperceptible contrast enhancement on conventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Batra, A.; Tripathi, R.P.; Singh, A.K.

    2004-01-01

    The purpose of the present paper was to evaluate the utility of perfusion MRI in cerebral gliomas showing imperceptible contrast enhancement on conventional MRI, and to evaluate the relationships of perfusion MRI and magnetic resonance (MR) spectroscopic results in these tumours. Twenty-two patients with histopathologically proven cerebral gliomas and showing insignificant contrast enhancement on conventional MR were included in the present study. All patients underwent perfusion MRI and MR spectroscopy on a 1.5-T MR system. Significant differences of the relative cerebral blood volume (rCBV) values and the choline : creatine ratios were noted between low-grade and anaplastic gliomas (P < 0.01). Good correlation was found between the rCBV values and the choline : creatine values (y = 0. 532x + 1.5643; r = 0.67). Perfusion MRI can be a useful tool in assessing the histopathological grade of non-contrast-enhancing cerebral gliomas. Along with MR spectroscopic imaging it can serve as an important technique for preoperative characterization of such gliomas, so that accurate targeting by stereotactic biopsies is possible. Copyright (2004) Blackwell Science Pty Ltd

  10. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nielsen, Gitte; Fritz-Hansen, Thomas; Dirks, Christina G

    2004-01-01

    with acute transmural myocardial infarction were studied using a Turbo-fast low angle shot (FLASH) MRI sequence to monitor the first pass of an extravascular contrast agent (CA), gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). Quantitation of perfusion, expressed as Ki (mL/100 g/minute), in five......PURPOSE: To investigate the diagnostic ability of quantitative magnetic resonance imaging (MRI) heart perfusion in acute heart patients, a fast, multislice dynamic contrast-enhanced MRI sequence was applied to patients with acute myocardial infarction. MATERIALS AND METHODS: Seven patients...

  11. Differences in perfusion parameters between upper and lower lumbar vertebral segments with dynamic contrast-enhanced MRI (DCE MRI)

    International Nuclear Information System (INIS)

    Savvopoulou, Vasiliki; Vlahos, Lampros; Moulopoulos, Lia Angela; Maris, Thomas G.

    2008-01-01

    To investigate the influence of age, sex and spinal level on perfusion parameters of normal lumbar bone marrow with dynamic contrast-enhanced MRI (DCE MRI). Sixty-seven subjects referred for evaluation of low back pain or sciatica underwent DCE MRI of the lumbar spine. After subtraction of dynamic images, a region of interest (ROI) was placed on each lumbar vertebral body of all subjects, and time intensity curves were generated. Consequently, perfusion parameters were calculated. Statistical analysis was performed to search for perfusion differences among lumbar vertebrae and in relation to age and sex. Upper (L1, L2) and lower (L3, L4, L5) vertebrae showed significant differences in perfusion parameters (p<0.05). Vertebrae of subjects younger than 50 years showed significantly higher perfusion compared to vertebrae of older ones (p<0.05). Vertebrae of females demonstrated significantly increased perfusion compared to those of males of corresponding age (p<0.05). All perfusion parameters, except for washout (WOUT), showed a mild linear correlation with age. Time to maximum slope (TMSP) and time to peak (TTPK) showed the same correlation with sex (0.22< r<0.32, p<0.05). Our results indicate increased perfusion of the upper compared to the lower lumbar spine, of younger compared to older subjects and of females compared to males. (orig.)

  12. Differences in perfusion parameters between upper and lower lumbar vertebral segments with dynamic contrast-enhanced MRI (DCE MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Savvopoulou, Vasiliki; Vlahos, Lampros; Moulopoulos, Lia Angela [University of Athens, Areteion Hospital, Department of Radiology, Medical School, Athens (Greece); Maris, Thomas G. [University of Crete, Deparment of Medical Physics, Faculty of Medicine, Heraklion (Greece)

    2008-09-15

    To investigate the influence of age, sex and spinal level on perfusion parameters of normal lumbar bone marrow with dynamic contrast-enhanced MRI (DCE MRI). Sixty-seven subjects referred for evaluation of low back pain or sciatica underwent DCE MRI of the lumbar spine. After subtraction of dynamic images, a region of interest (ROI) was placed on each lumbar vertebral body of all subjects, and time intensity curves were generated. Consequently, perfusion parameters were calculated. Statistical analysis was performed to search for perfusion differences among lumbar vertebrae and in relation to age and sex. Upper (L1, L2) and lower (L3, L4, L5) vertebrae showed significant differences in perfusion parameters (p<0.05). Vertebrae of subjects younger than 50 years showed significantly higher perfusion compared to vertebrae of older ones (p<0.05). Vertebrae of females demonstrated significantly increased perfusion compared to those of males of corresponding age (p<0.05). All perfusion parameters, except for washout (WOUT), showed a mild linear correlation with age. Time to maximum slope (TMSP) and time to peak (TTPK) showed the same correlation with sex (0.22perfusion of the upper compared to the lower lumbar spine, of younger compared to older subjects and of females compared to males. (orig.)

  13. Quantitative pulmonary perfusion imaging with 3-dimensional, contrast-enhanced MR: regional difference in the perfusion parameters of healthy volunteers

    International Nuclear Information System (INIS)

    Kim, Song Soo; Seo, Joon Beom; Kim, Nam Kuk; Do, Kyung Hyun; Lee, Young Kyung; Song, Jae Woo; Lee, Jin Seong; Kim, Jin Hwan

    2007-01-01

    We wanted to evaluate the regional differences in such perfusion parameters as pulmonary blood flow (PBF), mean transit time (MTT) and pulmonary blood volume (PBV) in the entire lung of healthy volunteers with using three-dimensional, contrast-enhanced MR imaging (3D CEMRI). Six healthy volunteers underwent dynamic 3D CEMRI (TR/TE 2.7/0.6 msec; flip angle 40 .deg. ; matrix 128 x 96; reconstructed matrix 256 x 192; rectangular field of view 450 x 315 mm; coronal 100-150mm-thick x 10 slabs; temporal resolution 1.0 sec; 35 dynamic phases) For all subjects, 2 mL of Gd-DTPA mixed with 3 ml of physiologic saline was administered as a bolus at a rate of 5 mL/sec, and this was followed by 20 mL of physiologic saline flush. From the signal intensity-time curves, the PBF, MTT and PBV maps were generated using indicator dilution theories and the central volume principle on a pixel-by-pixel basis. A total of 54 round, 1-cm sized ROIs were placed in the lung in each subject (6 ROIs per slab x 9 slices except for the most posterior slab). The regional differences of the measured parameters were statistically evaluated in the gravitational direction and in the upper-mid-lower direction by one-way ANOVA tests. The calculated PBF, MTT and PBV in the entire lung were 141.8 ± 53.4 mL/100 mL/min (mean ± SD), 5.35 ± 1.38 sec, and 13.4 ± 6.48 mL/100mL, respectively. In the gravitational direction, there was a significant increase in the PBF and PBV as it goes to the posterior direction (ρ < 0.05). No statistical difference was found in PBF or PBV between the upper, mid and lower lung zone areas. Regional difference in the various perfusion parameters of the lung in healthy volunteers can be quantitatively assessed with performing 3D CEMRI

  14. Perfusion quantification in contrast-enhanced ultrasound (CEUS)--ready for research projects and routine clinical use.

    Science.gov (United States)

    Tranquart, F; Mercier, L; Frinking, P; Gaud, E; Arditi, M

    2012-07-01

    With contrast-enhanced ultrasound (CEUS) now established as a valuable imaging modality for many applications, a more specific demand has recently emerged for quantifying perfusion and using measured parameters as objective indicators for various disease states. However, CEUS perfusion quantification remains challenging and is not well integrated in daily clinical practice. The development of VueBox™ alleviates existing limitations and enables quantification in a standardized way. VueBox™ operates as an off-line software application, after dynamic contrast-enhanced ultrasound (DCE-US) is performed. It enables linearization of DICOM clips, assessment of perfusion using patented curve-fitting models, and generation of parametric images by synthesizing perfusion information at the pixel level using color coding. VueBox™ is compatible with most of the available ultrasound platforms (nonlinear contrast-enabled), has the ability to process both bolus and disruption-replenishment kinetics loops, allows analysis results and their context to be saved, and generates analysis reports automatically. Specific features have been added to VueBox™, such as fully automatic in-plane motion compensation and an easy-to-use clip editor. Processing time has been reduced as a result of parallel programming optimized for multi-core processors. A long list of perfusion parameters is available for each of the two administration modes to address all possible demands currently reported in the literature for diagnosis or treatment monitoring. In conclusion, VueBox™ is a valid and robust quantification tool to be used for standardizing perfusion quantification and to improve the reproducibility of results across centers. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Non-contrast-enhanced perfusion and ventilation assessment of the human lung by means of fourier decomposition in proton MRI.

    Science.gov (United States)

    Bauman, Grzegorz; Puderbach, Michael; Deimling, Michael; Jellus, Vladimir; Chefd'hotel, Christophe; Dinkel, Julien; Hintze, Christian; Kauczor, Hans-Ulrich; Schad, Lothar R

    2009-09-01

    Assessment of regional lung perfusion and ventilation has significant clinical value for the diagnosis and follow-up of pulmonary diseases. In this work a new method of non-contrast-enhanced functional lung MRI (not dependent on intravenous or inhalative contrast agents) is proposed. A two-dimensional (2D) true fast imaging with steady precession (TrueFISP) pulse sequence (TR/TE = 1.9 ms/0.8 ms, acquisition time [TA] = 112 ms/image) was implemented on a 1.5T whole-body MR scanner. The imaging protocol comprised sets of 198 lung images acquired with an imaging rate of 3.33 images/s in coronal and sagittal view. No electrocardiogram (ECG) or respiratory triggering was used. A nonrigid image registration algorithm was applied to compensate for respiratory motion. Rapid data acquisition allowed observing intensity changes in corresponding lung areas with respect to the cardiac and respiratory frequencies. After a Fourier analysis along the time domain, two spectral lines corresponding to both frequencies were used to calculate the perfusion- and ventilation-weighted images. The described method was applied in preliminary studies on volunteers and patients showing clinical relevance to obtain non-contrast-enhanced perfusion and ventilation data.

  16. Human cerebral blood volume measurements using dynamic contrast enhancement in comparison to dynamic susceptibility contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Artzi, Moran [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Liberman, Gilad; Vitinshtein, Faina; Aizenstein, Orna [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Nadav, Guy [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Faculty of Engineering, Tel Aviv (Israel); Blumenthal, Deborah T.; Bokstein, Felix [Tel Aviv Sourasky Medical Center, Neuro-Oncology Service, Tel Aviv (Israel); Bashat, Dafna Ben [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv (Israel)

    2015-07-15

    Cerebral blood volume (CBV) is an important parameter for the assessment of brain tumors, usually obtained using dynamic susceptibility contrast (DSC) MRI. However, this method often suffers from low spatial resolution and high sensitivity to susceptibility artifacts and usually does not take into account the effect of tissue permeability. The plasma volume (v{sub p}) can also be extracted from dynamic contrast enhancement (DCE) MRI. The aim of this study was to investigate whether DCE can be used for the measurement of cerebral blood volume in place of DSC for the assessment of patients with brain tumors. Twenty-eight subjects (17 healthy subjects and 11 patients with glioblastoma) were scanned using DCE and DSC. v{sub p} and CBV values were measured and compared in different brain components in healthy subjects and in the tumor area in patients. Significant high correlations were detected between v{sub p} and CBV in healthy subjects in the different brain components; white matter, gray matter, and arteries, correlating with the known increased tissue vascularity, and within the tumor area in patients. This work proposes the use of DCE as an alternative method to DSC for the assessment of blood volume, given the advantages of its higher spatial resolution, its lower sensitivity to susceptibility artifacts, and its ability to provide additional information regarding tissue permeability. (orig.)

  17. Dynamic contrast-enhanced ultrasound and transient arterial occlusion for quantification of arterial perfusion reserve in peripheral arterial disease

    International Nuclear Information System (INIS)

    Amarteifio, E.; Wormsbecher, S.; Krix, M.; Demirel, S.; Braun, S.; Delorme, S.; Böckler, D.; Kauczor, H.-U.; Weber, M.-A.

    2012-01-01

    Objective: To quantify muscular micro-perfusion and arterial perfusion reserve in peripheral arterial disease (PAD) with dynamic contrast-enhanced ultrasound (CEUS) and transient arterial occlusion. Materials and methods: This study had local institutional review board approval and written informed consent was obtained from all subjects. We examined the dominant lower leg of 40 PAD Fontaine stage IIb patients (mean age, 65 years) and 40 healthy volunteers (mean age, 54 years) with CEUS (7 MHz; MI, 0.28) during continuous intravenous infusion of 4.8 mL microbubbles. Transient arterial occlusion at mid-thigh level simulated physical exercise. With time–CEUS–intensity curves obtained from regions of interest within calf muscles, we derived the maximum CEUS signal after occlusion (max) and its time (t max ), slope to maximum (m), vascular response after occlusion (AUC post ), and analysed accuracy, receiver operating characteristic (ROC) curves, and correlations with ankle-brachial index (ABI) and walking distance. Results: All parameters differed in PAD and volunteers (p max was delayed (31.2 ± 13.6 vs. 16.7 ± 8.5 s, p post as optimal parameter combination for diagnosing PAD and therefore impaired arterial perfusion reserve. Conclusions: Dynamic CEUS with transient arterial occlusion quantifies muscular micro-perfusion and arterial perfusion reserve. The technique is accurate to diagnose PAD.

  18. Perfusion characteristics of late radiation injury of parotid glands: quantitative evaluation with dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Juan, Chun-Jung; Chen, Cheng-Yu.; Hsueh, Chun-Jen; Huang, Guo-Shu; Jen, Yee-Min; Liu, Hua-Shan; Wang, Chao-Ying; Chung, Hsiao-Wen; Liu, Yi-Jui; Chou, Yu-Ching; Chai, Yao-Te

    2009-01-01

    We aimed to quantitatively investigate the alteration of parotid perfusion after irradiation using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on a two-compartment tracer kinetic model. This study enrolled 19 patients (53.2±14.9 years) treated by head and neck radiotherapy and 19 age-relevant and sex-matched subjects as a control group. Perfusion parameters (K el , k 21 and A) of parotid glands were analyzed based on the Brix model from T1-weighted DCE-MRI. Suitability of the Brix model was evaluated via Monte Carlo simulation for the goodness-of-fit. Analysis of nonlinear goodness-of-fit showed that the Brix model is appropriate in evaluating the parotid perfusion (R 2 = 0.938±0.050). The irradiated parotid glands showed significantly lower K el (P 21 (P < 0.05) and consequently significantly higher value of peak enhancement (P<0.0005) and time-to-peak (P<0.0005) compared with non-irradiated ones, suggestive of gradual and prolonged accumulation and delayed wash-out of contrast agent due to increased extracellular extravascular space and decreased vascular permeability in the irradiated glands. Linear regression analysis showed dose-dependent perfusion changes of the irradiated parotid glands. We conclude that quantitative DCE-MRI is a potential tool in investigating parotid gland perfusion changes after radiotherapy. (orig.)

  19. Renal Cell Carcinoma Perfusion before and after Radiofrequency Ablation Measured with Dynamic Contrast Enhanced MRI: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Tze Min Wah

    2018-01-01

    Full Text Available Aim: To investigate if the early treatment effects of radiofrequency ablation (RFA on renal cell carcinoma (RCC can be detected with dynamic contrast enhanced (DCE-MRI and to correlate RCC perfusion with RFA treatment time. Materials and methods: 20 patients undergoing RFA of their 21 RCCs were evaluated with DCE-MRI before and at one month after RFA treatment. Perfusion was estimated using the maximum slope technique at two independent sittings. Total RCC blood flow was correlated with total RFA treatment time, tumour location, size and histology. Results: DCE-MRI examinations were successfully evaluated for 21 RCCs (size from 1.3 to 4 cm. Perfusion of the RCCs decreased significantly (p < 0.0001 from a mean of 203 (±80 mL/min/100 mL before RFA to 8.1 (±3.1 mL/min/100 mL after RFA with low intra-observer variability (r ≥ 0.99, p < 0.0001. There was an excellent correlation (r = 0.95 between time to complete ablation and pre-treatment total RCC blood flow. Tumours with an exophytic location exhibit the lowest mean RFA treatment time. Conclusion: DCE-MRI can detect early treatment effects by measuring RCC perfusion before and after RFA. Perfusion significantly decreases in the zone of ablation, suggesting that it may be useful for the assessment of treatment efficacy. Pre-RFA RCC blood flow may be used to predict RFA treatment time.

  20. Contrast enhancement by arterial perfusion during computed tomography (computed tomographic arteriography) of the pancreatic disease

    International Nuclear Information System (INIS)

    Takaki, Yukiari

    1983-01-01

    Computed tomographic arteriography (CTA) was performed on 52 cases of pancreatic disease in which was suspected clinically, and in which other method failed to yield a definitive diagnosis. For CTA, 65% meglumine diatrizoate 20 ml, diluted 1:3, was injected via a catherter inserted in an artery connected with the pancreas and the change with time of the pacreas CT number was studied. The normal pancreas stains deeply and the best contrast enhancement was obtained between 17 to 21 seconds after instillation of contrast medium. In the CTA findings in pancreatic cancer, low density areas with irregular internal structures are characteristic, and these characteristics were seen even in minute pancreatic cancers which could not be recognized by CT or the intravenous bolus injection method. On the other hand, in chronic pancreatitis, even when differentiation from pancreatic cancer is difficult with arterial and venous encasement in angiography, as long as the chronic pancreatitis is not very advanced ischemic changes are not seen, and this permits differentiation form normal pancreas. This also facilitates differentiation between pancreatitis and pancreatic cancer. In the intravenous bolus injection method, the chronological change of contrast enhancement in the pancreas was studied and the best contrast enhancement was obtained after 60 to 120 seconds. This method revealed no findings peculiar to pancreatic cancer. Based on the above, CTA was found to be useful for making in contributing to establishing a definitive diagnosis, detecting minute pancreatic cancer and to differentiate pancreatic cancer from chronic pancreatitis. (author)

  1. Accuracy and feasibility of dynamic contrast-enhanced 3D MR imaging in the assessment of lung perfusion: comparison with Tc-99 MAA perfusion scintigraphy

    International Nuclear Information System (INIS)

    Yilmaz, E.; Akkoclu, A.; Degirmenci, B.; Cooper, R.A.; Sengun, B.; Gulcu, A.; Osma, E.; Ucan, E.S.

    2005-01-01

    AIM: The aim of this study was to correlate findings of perfusion magnetic resonance imaging (MRI) and perfusion scintigraphy in cases where there was a suspicion of abnormal pulmonary vasculature, and to evaluate the usefulness of MRI in the detection of perfusion deficits of the lung. METHODS: In all, 17 patients with suspected abnormality of the pulmonary vasculature underwent dynamic contrast-enhanced MRI. T1-weighted 3D fast-field echo pulse sequences were obtained (TR/TE 3.3/1.58 ms; flip angle 30 deg ; slice thickness 12 to 15 mm). The dynamic study was acquired in the coronal plane following administration of 0.1 mmol/kg gadopentetate dimeglumine. A total of 8 to 10 sections repeated 20 to 25 times at intervals of 1 s were performed. Perfusion lung scintigraphy was carried out a maximum of 48 h before the MR examination in all cases. Two radiologists, who were blinded to the clinical data and results of other imaging methods, reviewed all coronal sections. MR perfusion images were independently assessed in terms of segmental or lobar perfusion defects in the 85 lobes of the 17 individuals, and the findings were compared with the results of scintigraphy. RESULTS: Of the 17 patients, 8 were found to have pulmonary emboli, 2 chronic obstructive pulmonary disease with emphysema, 2 bullous emphysema, 2 Takayasu arteritis and 1 had a hypoplastic pulmonary artery. Pulmonary perfusion was completely normal in 2 cases. In 35 lobes, perfusion defects were detected using both methods, in 4 with MR alone and in 9 only with scintigraphy. There was good agreement between MRI and scintigraphy findings (kappa=0.695). CONCLUSION: Pulmonary perfusion MRI is a new alternative to scintigraphy in the evaluation of pulmonary perfusion for various lung disorders. In addition, this technique allows measurement and quantification of pulmonary perfusion abnormalities

  2. Impaired glymphatic perfusion after strokes revealed by contrast-enhanced MRI: a new target for fibrinolysis?

    Science.gov (United States)

    Gaberel, Thomas; Gakuba, Clement; Goulay, Romain; Martinez De Lizarrondo, Sara; Hanouz, Jean-Luc; Emery, Evelyne; Touze, Emmanuel; Vivien, Denis; Gauberti, Maxime

    2014-10-01

    The aim of the present study was to investigate the impact of different stroke subtypes on the glymphatic system using MRI. We first improved and characterized an in vivo protocol to measure the perfusion of the glymphatic system using MRI after minimally invasive injection of a gadolinium chelate within the cisterna magna. Then, the integrity of the glymphatic system was evaluated in 4 stroke models in mice including subarachnoid hemorrhage (SAH), intracerebral hemorrhage, carotid ligature, and embolic ischemic stroke. We were able to reliably evaluate the glymphatic system function using MRI. Moreover, we provided evidence that the glymphatic system was severely impaired after SAH and in the acute phase of ischemic stroke, but was not altered after carotid ligature or in case of intracerebral hemorrhage. Notably, this alteration in glymphatic perfusion reduced brain clearance rate of low-molecular-weight compounds. Interestingly, glymphatic perfusion after SAH can be improved by intracerebroventricular injection of tissue-type plasminogen activator. Moreover, spontaneous arterial recanalization was associated with restoration of the glymphatic function after embolic ischemic stroke. SAH and acute ischemic stroke significantly impair the glymphatic system perfusion. In these contexts, injection of tissue-type plasminogen activator either intracerebroventricularly to clear perivascular spaces (for SAH) or intravenously to restore arterial patency (for ischemic stroke) may improve glymphatic function. © 2014 American Heart Association, Inc.

  3. Reproducibility of rest and exercise stress contrast-enhanced calf perfusion magnetic resonance imaging in peripheral arterial disease

    Directory of Open Access Journals (Sweden)

    Jiji Ronny S

    2013-01-01

    Full Text Available Abstract Background The purpose was to determine the reproducibility and utility of rest, exercise, and perfusion reserve (PR measures by contrast-enhanced (CE calf perfusion magnetic resonance imaging (MRI of the calf in normal subjects (NL and patients with peripheral arterial disease (PAD. Methods Eleven PAD patients with claudication (ankle-brachial index 0.67 ±0.14 and 16 age-matched NL underwent symptom-limited CE-MRI using a pedal ergometer. Tissue perfusion and arterial input were measured at rest and peak exercise after injection of 0.1 mM/kg of gadolinium-diethylnetriamine pentaacetic acid (Gd-DTPA. Tissue function (TF and arterial input function (AIF measurements were made from the slope of time-intensity curves in muscle and artery, respectively, and normalized to proton density signal to correct for coil inhomogeneity. Perfusion index (PI = TF/AIF. Perfusion reserve (PR = exercise TF/ rest TF. Intraclass correlation coefficient (ICC was calculated from 11 NL and 10 PAD with repeated MRI on a different day. Results Resting TF was low in NL and PAD (mean ± SD 0.25 ± 0.18 vs 0.35 ± 0.71, p = 0.59 but reproducible (ICC 0.76. Exercise TF was higher in NL than PAD (5.5 ± 3.2 vs. 3.4 ± 1.6, p = 0.04. Perfusion reserve was similar between groups and highly variable (28.6 ± 19.8 vs. 42.6 ± 41.0, p = 0.26. Exercise TF and PI were reproducible measures (ICC 0.63 and 0.60, respectively. Conclusion Although rest measures are reproducible, they are quite low, do not distinguish NL from PAD, and lead to variability in perfusion reserve measures. Exercise TF and PI are the most reproducible MRI perfusion measures in PAD for use in clinical trials.

  4. Dynamic Contrast-Enhanced Perfusion MRI of High Grade Brain Gliomas Obtained with Arterial or Venous Waveform Input Function.

    Science.gov (United States)

    Filice, Silvano; Crisi, Girolamo

    2016-01-01

    The aim of this study was to evaluate the differences in dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) perfusion estimates of high-grade brain gliomas (HGG) due to the use of an input function (IF) obtained respectively from arterial (AIF) and venous (VIF) approaches by two different commercially available software applications. This prospective study includes 20 patients with pathologically confirmed diagnosis of high-grade gliomas. The data source was processed by using two DCE dedicated commercial packages, both based on the extended Toft model, but the first customized to obtain input function from arterial measurement and the second from sagittal sinus sampling. The quantitative parametric perfusion maps estimated from the two software packages were compared by means of a region of interest (ROI) analysis. The resulting input functions from venous and arterial data were also compared. No significant difference has been found between the perfusion parameters obtained with the two different software packages (P-value < .05). The comparison of the VIFs and AIFs obtained by the two packages showed no statistical differences. Direct comparison of DCE-MRI measurements with IF generated by means of arterial or venous waveform led to no statistical difference in quantitative metrics for evaluating HGG. However, additional research involving DCE-MRI acquisition protocols and post-processing would be beneficial to further substantiate the effectiveness of venous approach as the IF method compared with arterial-based IF measurement. Copyright © 2015 by the American Society of Neuroimaging.

  5. Dynamic iterative beam hardening correction (DIBHC) in myocardial perfusion imaging using contrast-enhanced computed tomography.

    Science.gov (United States)

    Stenner, Philip; Schmidt, Bernhard; Allmendinger, Thomas; Flohr, Thomas; Kachelrie, Marc

    2010-06-01

    In cardiac perfusion examinations with computed tomography (CT) large concentrations of iodine in the ventricle and in the descending aorta cause beam hardening artifacts that can lead to incorrect perfusion parameters. The aim of this study is to reduce these artifacts by performing an iterative correction and by accounting for the 3 materials soft tissue, bone, and iodine. Beam hardening corrections are either implemented as simple precorrections which cannot account for higher order beam hardening effects, or as iterative approaches that are based on segmenting the original image into material distribution images. Conventional segmentation algorithms fail to clearly distinguish between iodine and bone. Our new algorithm, DIBHC, calculates the time-dependent iodine distribution by analyzing the voxel changes of a cardiac perfusion examination (typically N approximately 15 electrocardiogram-correlated scans distributed over a total scan time up to T approximately 30 s). These voxel dynamics are due to changes in contrast agent. This prior information allows to precisely distinguish between bone and iodine and is key to DIBHC where each iteration consists of a multimaterial (soft tissue, bone, iodine) polychromatic forward projection, a raw data comparison and a filtered backprojection. Simulations with a semi-anthropomorphic dynamic phantom and clinical scans using a dual source CT scanner with 2 x 128 slices, a tube voltage of 100 kV, a tube current of 180 mAs, and a rotation time of 0.28 seconds have been carried out. The uncorrected images suffer from beam hardening artifacts that appear as dark bands connecting large concentrations of iodine in the ventricle, aorta, and bony structures. The CT-values of the affected tissue are usually underestimated by roughly 20 HU although deviations of up to 61 HU have been observed. For a quantitative evaluation circular regions of interest have been analyzed. After application of DIBHC the mean values obtained deviate by

  6. Dynamic contrast-enhanced perfusion studies of the brain with snapshot FLASH

    International Nuclear Information System (INIS)

    Finelli, D.A.; Kiefer, B.; Deimling, M.; Loeffler, W.; Haase, A.; Schuierer, G.

    1989-01-01

    This paper discusses how MR imaging with Gd-DTPA can improve the diagnostic accuracy of brain examinations. Conventional T1-weighted spin-echo sequences have been most satisfactory for depicting lesion enhancement following Gd-DTPA administration, however, the ability to examine the blood pool and early biodistribution phases has been limited. A new ultrafast MR imaging technique called Snapshot FLASH allows one to acquire entire images in 125-900 msec, with strong T1- or T2-weighted contrast. With this imaging technique, one can observe differential perfusion to the gray matter, while matter, and brain lesions during the first seconds following Gd-DTPA administration

  7. Dynamic contrast-enhanced MR imaging to assess physiologic variations of myometrial perfusion

    International Nuclear Information System (INIS)

    Thomassin-Naggara, Isabelle; Balvay, Daniel; Cuenod, Charles A.; Darai, Emile; Marsault, Claude; Bazot, Marc

    2010-01-01

    To prospectively evaluate the ability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess physiological microvascular states in normal myometrium. Eighty-five women (62 women of reproductive age, 23 postmenopausal) undergoing DCE-MRI of the pelvis were included. Microvascular parameters for the inner and outer myometrium were analysed using a pharmacokinetic model. These parameters were tissue blood flow (F), blood volume fraction (V b ), permeability-surface area product (PS), interstitial volume fraction (V e ) and lag time (Dt). In the women of reproductive age, the inner myometrium displayed higher F and PS, lower V b and V e , and longer Dt than the outer myometrium (p = 0.02, p = 0.01, p = 0.005, p = 0.03 and p = 0.01, respectively). The inner myometrium presented microvascular variations during the menstrual cycle with a pre-ovulatory peak followed by a fall reaching a nadir of F and V b about 4 days after ovulation. Compared with women of reproductive age, in the postmenopausal state, F and V b decreased in the outer myometrium, while PS, V e and Dt increased (p < 0.0001, p = 0.001, p = 0.001, p = 0.03 and p = 0.0004, respectively). DCE-MRI is a non-invasive technique that can measure variations of myometrial microcirculation, and thereby be potentially useful to help characterize the role and states of the myometrium in assisted reproductive therapy. (orig.)

  8. Perfusion characteristics of parotid gland tumors evaluated by contrast-enhanced ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, Laura V., E-mail: Laura.Klotz@med.uni-muenchen.de [Department of Surgery, University of Munich, Munich (Germany); Gürkov, Robert [Department of Otorhinolaryngology, University of Munich, Munich (Germany); Eichhorn, Martin E. [Department of Surgery, University of Munich, Munich (Germany); Siedek, Vanessa; Krause, Eike [Department of Otorhinolaryngology, University of Munich, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, University of Munich, Munich (Germany); Reiser, Maximilian F.; Clevert, Dirk-Andre [Department of Clinical Radiology, University of Munich, Munich (Germany)

    2013-12-01

    Purpose: Contrast enhanced ultrasound (CE-US) is a promising imaging modality for non-invasive analysis of parotid gland lesions because their vascularisation differs from normal gland tissue. This clinical study should further investigate CE-US as a diagnostic tool for parotid gland tumors. Materials and methods: 39 patients underwent CE-US measurements after intravenous application of a contrast agent (SonoVue, Bracco, Italy) before surgical tumor resection. Time–intensity curves gradients were calculated and parameters of intratumoral microcirculation were analysed. The vascularisation parameters were compared among the different tumor entities as defined per definitive histological diagnosis. Results: Histological analyses revealed 17 pleomorphic adenoma, 15 cystadenolymphoma and 7 malignoma. A significant difference of area below intensity time curve (AUC) and mean transit time (MTT) was measured in the malignant lesions compared to benign tumors (p < 0.05). A significant difference of AUC and maximum of signal increase (ΔSI{sub max}) for pleomorphic adenoma versus cystadenolymphoma was found (p < 0.05). Conclusion: CE-US seems to be a quantitative and independent method for the assessment of malign and benign parotid gland tumors. Further studies and clinical experience will have to validate this method as a reliable diagnostic tool that facilitates preoperative planning.

  9. Evaluation of dynamic contrast-enhanced T1-weighted perfusion MRI in the differentiation of tumor recurrence from radiation necrosis

    DEFF Research Database (Denmark)

    Larsen, Anne Vibeke Andrée; Simonsen, Helle J; Law, Ian

    2013-01-01

    INTRODUCTION: To investigate if perfusion measured with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can be used to differentiate radiation necrosis from tumor recurrence in patients with high-grade glioma. METHODS: The study was approved by the institutional review board...... to measure cerebral blood volume (CBV), blood-brain barrier (BBB) permeability and cerebral blood flow (CBF). Subjects also underwent FDG-PET and lesions were classified as either metabolically active or inactive. Follow-up clinical MRI and lesion histology in case of additional tissue resection was used...... to determine whether lesions were regressing or progressing. RESULTS: Fourteen enhancing lesions could be classified as progressing (11) or regressing (three). An empirical threshold of 2.0 ml/100 g for CBV allowed detection of regressing lesions with a sensitivity of 100 % and specificity of 100 %. FDG-PET...

  10. Dynamic contrast-enhanced MR imaging to assess physiologic variations of myometrial perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin-Naggara, Isabelle [Assistance Publique-Hopitaux de Paris, Department of Radiology, Hopital Tenon, Paris (France); Universite Rene Descartes, Laboratoire de Recherche en Imagerie-INSERM U970, Paris (France); Hopital Tenon, Service de Radiologie, Paris (France); Balvay, Daniel [Universite Rene Descartes, Laboratoire de Recherche en Imagerie-INSERM U970, Paris (France); Cuenod, Charles A. [Universite Rene Descartes, Laboratoire de Recherche en Imagerie-INSERM U970, Paris (France); Hopital Europeen Georges Pompidou (HEGP), Department of Radiology, Paris (France); Darai, Emile [Assistance Publique-Hopitaux de Paris, Department of Gynaecology-Obstetrics, Hopital Tenon, Paris (France); Marsault, Claude; Bazot, Marc [Assistance Publique-Hopitaux de Paris, Department of Radiology, Hopital Tenon, Paris (France)

    2010-04-15

    To prospectively evaluate the ability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess physiological microvascular states in normal myometrium. Eighty-five women (62 women of reproductive age, 23 postmenopausal) undergoing DCE-MRI of the pelvis were included. Microvascular parameters for the inner and outer myometrium were analysed using a pharmacokinetic model. These parameters were tissue blood flow (F), blood volume fraction (V{sub b}), permeability-surface area product (PS), interstitial volume fraction (V{sub e}) and lag time (Dt). In the women of reproductive age, the inner myometrium displayed higher F and PS, lower V{sub b} and V{sub e}, and longer Dt than the outer myometrium (p = 0.02, p = 0.01, p = 0.005, p = 0.03 and p = 0.01, respectively). The inner myometrium presented microvascular variations during the menstrual cycle with a pre-ovulatory peak followed by a fall reaching a nadir of F and V{sub b} about 4 days after ovulation. Compared with women of reproductive age, in the postmenopausal state, F and V{sub b} decreased in the outer myometrium, while PS, V{sub e} and Dt increased (p < 0.0001, p = 0.001, p = 0.001, p = 0.03 and p = 0.0004, respectively). DCE-MRI is a non-invasive technique that can measure variations of myometrial microcirculation, and thereby be potentially useful to help characterize the role and states of the myometrium in assisted reproductive therapy. (orig.)

  11. Severe portal hypertension in cirrhosis: evaluation of perfusion parameters with contrast-enhanced ultrasonography.

    Directory of Open Access Journals (Sweden)

    Woo Kyoung Jeong

    Full Text Available To investigate the role of contrast-enhanced ultrasonography (CEUS and Doppler ultrasonography (DUS in the diagnosis of severe portal hypertension (PH in patients with liver cirrhosis (LC.Patients with PH scheduled to receive hepatic venous pressure gradient (HVPG measurement were recruited for this study. Hepatic DUS and CEUS were performed successively. Several Doppler and CEUS parameters were explored for correlation with HVPG values and their association with severe PH (≥ 12 mmHg of HVPG. Comparison of the parameters between the severe and non-severe PH groups and their correlation with HVPG values was evaluated. A receiver operating characteristic (ROC curve analysis was also performed to investigate the performance in order to diagnose severe PH.Fifty-three consecutive patients were enrolled in this study. Among them, 43 patients did not have significant ascites. Compared with the non-severe PH group, portal venous velocity and intrahepatic transit time (ITT were significantly reduced in the severe PH group (all p<0.05. Difference between inspiratory and expiratory hepatic venous damping indices (ΔHVDI, hepatic venous arrival time (HVAT and ITT moderately correlated with HVPG (r = -0.358, -0.338, and -0.613, respectively. Areas under the curves for severe PH were 0.94 of ITT and 0.72 of HVAT, respectively (all p<0.05. ITT under 6 seconds indicated severe PH with a sensitivity of 92% and a specificity of 89%.Hepatic CEUS may be more useful in estimating the HVPG value and determining the presence of severe PH compared to DUS, and ITT was the most accurate parameter to diagnose severe PH.

  12. Prognostic value of preoperative dynamic contrast-enhanced MRI perfusion parameters for high-grade glioma patients

    Energy Technology Data Exchange (ETDEWEB)

    Ulyte, Agne [Vilnius University, Faculty of Medicine, Vilnius (Lithuania); Katsaros, Vasileios K. [General Anticancer and Oncological Hospital ' ' St. Savvas' ' , Department of Advanced Imaging Modalities - CT and MRI, Athens (Greece); University of Athens, Department of Neurosurgery, Evangelismos Hospital, Athens (Greece); Liouta, Evangelia; Stranjalis, Georgios [University of Athens, Department of Neurosurgery, Evangelismos Hospital, Athens (Greece); Boskos, Christos [University of Athens, Department of Neurosurgery, Evangelismos Hospital, Athens (Greece); General Anticancer and Oncological Hospital ' ' St. Savvas' ' , Department of Radiation Oncology, Athens (Greece); Papanikolaou, Nickolas [Champalimaud Foundation, Department of Radiology, Centre for the Unknown, Lisbon (Portugal); Usinskiene, Jurgita [National Cancer Institute, Vilnius (Lithuania); Affidea Lietuva, Vilnius (Lithuania); Bisdas, Sotirios [University College London Hospitals, Department of Neuroradiology, The National Hospital for Neurology and Neurosurgery, London (United Kingdom)

    2016-12-15

    The prognostic value of the dynamic contrast-enhanced (DCE) MRI perfusion and its histogram analysis-derived metrics is not well established for high-grade glioma (HGG) patients. The aim of this prospective study was to investigate DCE perfusion transfer coefficient (K{sup trans}), vascular plasma volume fraction (v{sub p}), extracellular volume fraction (v{sub e}), reverse transfer constant (k{sub ep}), and initial area under gadolinium concentration time curve (IAUGC) as predictors of progression-free (PFS) and overall survival (OS) in HGG patients. Sixty-nine patients with suspected anaplastic astrocytoma or glioblastoma underwent preoperative DCE-MRI scans. DCE perfusion whole tumor region histogram parameters, clinical details, and PFS and OS data were obtained. Univariate, multivariate, and Kaplan-Meier survival analyses were conducted. Receiver operating characteristic (ROC) curve analysis was employed to identify perfusion parameters with the best differentiation performance. On univariate analysis, v{sub e} and skewness of v{sub p} had significant negative impacts, while k{sub ep} had significant positive impact on OS (P < 0.05). v{sub e} was also a negative predictor of PFS (P < 0.05). Patients with lower v{sub e} and IAUGC had longer median PFS and OS on Kaplan-Meier analysis (P < 0.05). K{sup trans} and v{sub e} could also differentiate grade III from IV gliomas (area under the curve 0.819 and 0.791, respectively). High v{sub e} is a consistent predictor of worse PFS and OS in HGG glioma patients. v{sub p} skewness and k{sub ep} are also predictive for OS. K{sup trans} and v{sub e} demonstrated the best diagnostic performance for differentiating grade III from IV gliomas. (orig.)

  13. Multimodality functional imaging of spontaneous canine tumors using 64CU-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

    DEFF Research Database (Denmark)

    Hansen, Anders E; Kristensen, Annemarie T; Law, Ian

    2012-01-01

    To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated.......To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated....

  14. Comparison between perfusion computed tomography and dynamic contrast-enhanced magnetic resonance imaging in assessing glioblastoma microvasculature

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Zhong Zheng, E-mail: jzz2397@163.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China); Shi, Wei, E-mail: sw740104@hotmail.com [Department of Neurosurgery, Affiliated Hospital of Nantong University, 20 Xisi Road, Nantong 226001, Jiangsu (China); Shi, Jin Long, E-mail: shij_ns@163.com [Department of Neurosurgery, Affiliated Hospital of Nantong University, 20 Xisi Road, Nantong 226001, Jiangsu (China); Shen, Dan Dan, E-mail: 1021121084@qq.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China); Gu, Hong Mei, E-mail: guhongmei71@163.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China); Zhou, Xue Jun, E-mail: 56516400@qq.com [Department of Radiology, Affiliated Hospital of Nantong University, No. 20 Xisi Road Nantong 226001, Jiangsu (China)

    2017-02-15

    Purpose: Perfusion computed tomography (PCT) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) provide independent measurements of biomarkers related to tumor perfusion. The aim of this study was to compare the two techniques in assessing glioblastoma microvasculature. Materials and methods: Twenty-five patients diagnosed with glioblastoma (14 males and 11 females; 51 ± 11 years old, ranging from 33 to 70 years) were includede in this prospective study. All patients underwent both PCT and DCE-MRI. Imaging was performed on a 256-slice CT scanner and a 3-T MRI system. PCT yielded permeability surface-area product (PS) using deconvolution physiological models; meanwhile, DCE-MRI determined volume transfer constant (K{sup trans}) using the Tofts-Kermode compartment model. All cases were submitted to surgical intervention, and CD105-microvascular density (CD105-MVD) was measured in each glioblastoma specimen. Then, Spearman’s correlation coefficients and Bland-Altman plots were obtained for PS, K{sup trans} and CD105-MVD. P < 0.05 was considered statistically significant. Results: Tumor PS and K{sup trans} values were correlated with CD105-MVD (r = 0.644, P < 0.001; r = 0.683, P < 0.001). In addition, PS was correlated with K{sup trans} in glioblastoma (r = 0.931, P < 0.001). Finally, Bland-Altman plots showed no significant differences between PS and K{sup trans} (P = 0.063). Conclusion: PCT and DCE-MRI measurements of glioblastoma perfusion biomarkers have similar results, suggesting that both techniques may have comparable utility. Therefore, PCT may serve as an alternative modality to DCE-MRI for the in vivo evaluation of glioblastoma microvasculature.

  15. Diagnostic accuracy of unenhanced, contrast-enhanced perfusion and angiographic MRI sequences for pulmonary embolism diagnosis: results of independent sequence readings

    Energy Technology Data Exchange (ETDEWEB)

    Revel, Marie Pierre [Hopital Europeen Georges Pompidou, APHP, Departments of Radiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); Hotel-Dieu, Service de Radiologie, Paris (France); Sanchez, Olivier; Meyer, Guy [Hopital Europeen Georges Pompidou, APHP, Respiratory and intensive care and, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); INSERM Unite 765, Paris (France); Lefort, Catherine; Couchon, Sophie; Hernigou, Anne; Frija, Guy [Hopital Europeen Georges Pompidou, APHP, Departments of Radiology, Paris (France); Niarra, Ralph [Hopital Europeen Georges Pompidou, APHP, Clinical Epidemiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); Chatellier, Gilles [Hopital Europeen Georges Pompidou, APHP, Clinical Epidemiology, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Paris (France); INSERM CIC-EC E4, Paris (France)

    2013-09-15

    To independently evaluate unenhanced, contrast-enhanced perfusion and angiographic MR sequences for pulmonary embolism (PE) diagnosis. Prospective investigation, including 274 patients who underwent perfusion, unenhanced 2D steady-state-free-precession (SSFP) and contrast-enhanced 3D angiographic MR sequences on a 1.5-T unit, in addition to CTA (CT angiography). Two independent readers evaluated each sequence independently in random order. Sensitivity, specificity, predictive values and inter-reader agreement were calculated for each sequence, excluding sequences judged inconclusive. Sensitivity was also calculated according to PE location. Contrast-enhanced angiographic sequences showed the highest sensitivity (82.9 and 89.7 %, reader 1 and reader 2, respectively), specificity (98.5 and 100 %) and agreement (kappa value 0.77). Unenhanced angiographic sequences, although less sensitive overall (68.7 and 76.4 %), were sensitive for the detection of proximal PE (92.7 and 100 %) and showed high specificity (96.1 and 99.1 %) and good agreement (kappa value 0.62). Perfusion sequences showed lower sensitivity (75.0 and 79.3 %), specificity (84.8 and 89.7 %) and agreement (kappa value 0.51), and a negative predictive value of 84.8 % at best. Compared with contrast-enhanced angiographic sequences, unenhanced sequences demonstrate lower sensitivity, except for proximal PE, but high specificity and agreement. The negative predictive value of perfusion sequences was insufficient to safely rule out PE. (orig.)

  16. Assessment of perfusion by dynamic contrast-enhanced imaging using a deconvolution approach based on regression and singular value decomposition.

    Science.gov (United States)

    Koh, T S; Wu, X Y; Cheong, L H; Lim, C C T

    2004-12-01

    The assessment of tissue perfusion by dynamic contrast-enhanced (DCE) imaging involves a deconvolution process. For analysis of DCE imaging data, we implemented a regression approach to select appropriate regularization parameters for deconvolution using the standard and generalized singular value decomposition methods. Monte Carlo simulation experiments were carried out to study the performance and to compare with other existing methods used for deconvolution analysis of DCE imaging data. The present approach is found to be robust and reliable at the levels of noise commonly encountered in DCE imaging, and for different models of the underlying tissue vasculature. The advantages of the present method, as compared with previous methods, include its efficiency of computation, ability to achieve adequate regularization to reproduce less noisy solutions, and that it does not require prior knowledge of the noise condition. The proposed method is applied on actual patient study cases with brain tumors and ischemic stroke, to illustrate its applicability as a clinical tool for diagnosis and assessment of treatment response.

  17. Response Assessment in Neuro-Oncology criteria, contrast enhancement and perfusion MRI for assessing progression in glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Tensaouti, Fatima [Universite de Toulouse, Inserm, UPS, ToNIC, Toulouse NeuroImaging Center, Toulouse (France); Khalifa, Jonathan [Claudius Regaud Institute / Toulouse University Cancer Institute - Oncopole, Department of Radiation Oncology, Toulouse (France); Lusque, Amelie [Claudius Regaud Institute / Toulouse University Cancer Institute - Oncopole, Department of Biostatistics, Toulouse (France); Plas, Benjamin [CHU Toulouse, Department of Neurosurgery, Toulouse (France); Lotterie, Jean Albert; Berry, Isabelle [Universite de Toulouse, Inserm, UPS, ToNIC, Toulouse NeuroImaging Center, Toulouse (France); CHU Toulouse, Department of Nuclear Medicine, Toulouse (France); Laprie, Anne [Universite de Toulouse, Inserm, UPS, ToNIC, Toulouse NeuroImaging Center, Toulouse (France); Claudius Regaud Institute / Toulouse University Cancer Institute - Oncopole, Department of Radiation Oncology, Toulouse (France); Cohen-Jonathan Moyal, Elizabeth [Claudius Regaud Institute / Toulouse University Cancer Institute - Oncopole, Department of Radiation Oncology, Toulouse (France); Toulouse Center for Cancer Research (U1037), Inserm, Toulouse (France); Lubrano, Vincent [Universite de Toulouse, Inserm, UPS, ToNIC, Toulouse NeuroImaging Center, Toulouse (France); CHU Toulouse, Department of Neurosurgery, Toulouse (France)

    2017-10-15

    The purpose of the study was to evaluate Response Assessment in Neuro-Oncology (RANO) criteria in glioblastoma multiforme (GBM), with respect to the Macdonald criteria and changes in contrast-enhancement (CE) volume. Related variations in relative cerebral blood volume (rCBV) were investigated. Forty-three patients diagnosed between 2006 and 2010 were included. All underwent surgical resection, followed by temozolomide-based chemoradiation. MR images were retrospectively reviewed. Times to progression (TTPs) according to RANO criteria, Macdonald criteria and increased CE volume (CE-3D) were compared, and the percentage change in the 75th percentile of rCBV (rCBV75) was evaluated. After a median follow-up of 22.7 months, a total of 39 patients had progressed according to RANO criteria, 32 according to CE-3D, and 42 according to Macdonald. Median TTPs were 6.4, 9.3, and 6.6 months, respectively. Overall agreement was 79.07% between RANO and CE-3D and 93.02% between RANO and Macdonald. The mean percentage change in rCBV75 at RANO progression onset was over 73% in 87.5% of patients. In conclusion, our findings suggest that CE-3D criterion is not yet suitable to assess progression in routine clinical practice. Indeed, the accurate threshold is still not well defined. To date, in our opinion, early detection of disease progression by RANO combined with advanced MRI imaging techniques like MRI perfusion and diffusion remains the best way to assess disease progression. Further investigations that would examine the impact of treatment modifications after progression determined by different criteria on overall survival would be of great value. (orig.)

  18. Response Assessment in Neuro-Oncology criteria, contrast enhancement and perfusion MRI for assessing progression in glioblastoma

    International Nuclear Information System (INIS)

    Tensaouti, Fatima; Khalifa, Jonathan; Lusque, Amelie; Plas, Benjamin; Lotterie, Jean Albert; Berry, Isabelle; Laprie, Anne; Cohen-Jonathan Moyal, Elizabeth; Lubrano, Vincent

    2017-01-01

    The purpose of the study was to evaluate Response Assessment in Neuro-Oncology (RANO) criteria in glioblastoma multiforme (GBM), with respect to the Macdonald criteria and changes in contrast-enhancement (CE) volume. Related variations in relative cerebral blood volume (rCBV) were investigated. Forty-three patients diagnosed between 2006 and 2010 were included. All underwent surgical resection, followed by temozolomide-based chemoradiation. MR images were retrospectively reviewed. Times to progression (TTPs) according to RANO criteria, Macdonald criteria and increased CE volume (CE-3D) were compared, and the percentage change in the 75th percentile of rCBV (rCBV75) was evaluated. After a median follow-up of 22.7 months, a total of 39 patients had progressed according to RANO criteria, 32 according to CE-3D, and 42 according to Macdonald. Median TTPs were 6.4, 9.3, and 6.6 months, respectively. Overall agreement was 79.07% between RANO and CE-3D and 93.02% between RANO and Macdonald. The mean percentage change in rCBV75 at RANO progression onset was over 73% in 87.5% of patients. In conclusion, our findings suggest that CE-3D criterion is not yet suitable to assess progression in routine clinical practice. Indeed, the accurate threshold is still not well defined. To date, in our opinion, early detection of disease progression by RANO combined with advanced MRI imaging techniques like MRI perfusion and diffusion remains the best way to assess disease progression. Further investigations that would examine the impact of treatment modifications after progression determined by different criteria on overall survival would be of great value. (orig.)

  19. Detection of Local Tumor Recurrence After Definitive Treatment of Head and Neck Squamous Cell Carcinoma: Histogram Analysis of Dynamic Contrast-Enhanced T1-Weighted Perfusion MRI.

    Science.gov (United States)

    Choi, Sang Hyun; Lee, Jeong Hyun; Choi, Young Jun; Park, Ji Eun; Sung, Yu Sub; Kim, Namkug; Baek, Jung Hwan

    2017-01-01

    This study aimed to explore the added value of histogram analysis of the ratio of initial to final 90-second time-signal intensity AUC (AUCR) for differentiating local tumor recurrence from contrast-enhancing scar on follow-up dynamic contrast-enhanced T1-weighted perfusion MRI of patients treated for head and neck squamous cell carcinoma (HNSCC). AUCR histogram parameters were assessed among tumor recurrence (n = 19) and contrast-enhancing scar (n = 27) at primary sites and compared using the t test. ROC analysis was used to determine the best differentiating parameters. The added value of AUCR histogram parameters was assessed when they were added to inconclusive conventional MRI results. Histogram analysis showed statistically significant differences in the 50th, 75th, and 90th percentiles of the AUCR values between the two groups (p Histogram analysis of AUCR can improve the diagnostic yield for local tumor recurrence during surveillance after treatment for HNSCC.

  20. Perfusion parameters of dynamic contrast-enhanced magnetic resonance imaging in patients with rectal cancer: Correlation with microvascular density and vascular endothelial growth factor expression

    International Nuclear Information System (INIS)

    Kim, Yeo Eun; Lim, Joon Seok; Kim, Myeong Jin; Kim, Ki Whang; Choi, Jun Jeong; Kim, Dae Hong; Myoung, Sung Min

    2013-01-01

    To determine whether quantitative perfusion parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) correlate with immunohistochemical markers of angiogenesis in rectal cancer. Preoperative DCE-MRI was performed in 63 patients with rectal adenocarcinoma. Transendothelial volume transfer (K trans ) and fractional volume of the extravascular-extracellular space (Ve) were measured by Interactive Data Language software in rectal cancer. After surgery, microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression scores were determined using immunohistochemical staining of rectal cancer specimens. Perfusion parameters (K trans , Ve) of DCE-MRI in rectal cancer were found to be correlated with MVD and VEGF expression scores by Spearman's rank coefficient analysis. T stage and N stage (negative or positive) were correlated with perfusion parameters and MVD. Significant correlation was not found between any DCE-MRI perfusion parameters and MVD (rs = -0.056 and p 0.662 for K trans ; rs = -0.103 and p = 0.416 for Ve), or between any DCE-MRI perfusion parameters and the VEGF expression score (rs = -0.042, p 0.741 for K trans ; r = 0.086, p = 0.497 for Ve) in rectal cancer. TN stage showed no significant correlation with perfusion parameters or MVD (p > 0.05 for all). DCE-MRI perfusion parameters, K trans and Ve, correlated poorly with MVD and VEGF expression scores in rectal cancer, suggesting that these parameters do not simply denote static histological vascular properties.

  1. Magnetic Resonance Imaging Susceptibility-Weighted Imaging Lesion and Contrast Enhancement May Represent Infectious Intracranial Aneurysm in Infective Endocarditis.

    Science.gov (United States)

    Cho, Sung-Min; Rice, Cory; Marquardt, Robert J; Zhang, Lucy Q; Khoury, Jean; Thatikunta, Prateek; Buletko, Andrew B; Hardman, Julian; Uchino, Ken; Wisco, Dolora

    2017-01-01

    Infectious intracranial aneurysm (IIA) can complicate infective endocarditis (IE). We aimed to describe the magnetic resonance imaging (MRI) characteristics of IIA. We reviewed IIAs among 116 consecutive patients with active IE by conducting a neurological evaluation at a single tertiary referral center from January 2015 to July 2016. MRIs and digital cerebral angiograms (DSA) were reviewed to identify MRI characteristics of IIAs. MRI susceptibility weighted imaging (SWI) was performed to collect data on cerebral microbleeds (CMBs) and sulcal SWI lesions. Out of 116 persons, 74 (63.8%) underwent DSA. IIAs were identified in 13 (17.6% of DSA, 11.2% of entire cohort) and 10 patients with aneurysms underwent MRI with SWI sequence. Nine (90%) out of 10 persons with IIAs had CMB >5 mm or sulcal lesions in SWI (9 in sulci, 6 in parenchyma, and 5 in both). Five out of 8 persons who underwent MRI brain with contrast had enhancement within the SWI lesions. In a multivariate logistic regression analysis, both sulcal SWI lesions (p < 0.001, OR 69, 95% CI 7.8-610) and contrast enhancement (p = 0.007, OR 16.5, 95% CI 2.3-121) were found to be significant predictors of the presence of IIAs. In the individuals with IE who underwent DSA and MRI, we found that neuroimaging characteristics, such as sulcal SWI lesion with or without contrast enhancement, are associated with the presence of IIA. © 2017 S. Karger AG, Basel.

  2. Contrast enhanced susceptibility weighted imaging (CE-SWI) of the mouse brain using ultrasmall superparamagnetic ironoxide particles (USPIO)

    International Nuclear Information System (INIS)

    Hamans, B.C.; Heerschap, A.; Barth, M.; Leenders, W.P.

    2006-01-01

    Susceptibility weighted imaging (SWI) has been introduced as a novel approach to visualize the venous vasculature in the human brain. With SWI, small veins in the brain are depicted based on the susceptibility difference between deoxyhaemoglobin in the veins and surrounding tissue, which is further enhanced by the use of MR phase information. In this study we applied SWI in the mouse brain using an exogenous iron-based blood-pool contrast agent, with the aims of further enhancing the susceptibility effect and allowing the visualization of individual veins and arteries. Contrast enhanced (CE-) SWI of the brain was performed on healthy mice and mice carrying intracerebral glioma xenografts. This study demonstrates that detailed vascular information in the mouse brain can be obtained by using CE-SWI and is substantially enhanced compared to native SWI (i.e. without contrast agent). CE-SWI images of tumour-bearing mice were directly compared to histology, confirming that CE-SWI depicts the vessels supplying and draining the tumour. We propose that CE-SWI is a very promising tool for the characterization of tumour vasculature. (orig.)

  3. Early changes in perfusion of glioblastoma during radio- and chemotherapy evaluated by T1-dynamic contrast enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Møller, Søren; Lundemann, Michael; Law, Ian

    2015-01-01

    months post-Tx. DCE-MRI at three Tesla generated maps of blood flow (BF), blood volume (BV), permeability (Ki) and volume of distribution (Vd) using a combination of model-free deconvolution and Patlak plots. Regions of interest in contrast enhancing tumor and in normal appearing white matter were...

  4. Contrast-enhanced 3T MR perfusion of musculoskeletal tumours. T1 value heterogeneity assessment and evaluation of the influence of T1 estimation methods on quantitative parameters

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto; Leplat, Christophe; Verbizier, Jacques de; Blum, Alain [Hopital Central, CHRU-Nancy, Service d' Imagerie Guilloz, Nancy (France); Chen, Bailiang; Beaumont, Marine [Universite de Lorraine, Laboratoire IADI, UMR S 947, Nancy (France); Badr, Sammy; Cotten, Anne [CHRU Lille Centre de Consultations et d' Imagerie de l' Appareil Locomoteur, Department of Radiology and Musculoskeletal Imaging, Lille (France)

    2017-12-15

    To evaluate intra-tumour and striated muscle T1 value heterogeneity and the influence of different methods of T1 estimation on the variability of quantitative perfusion parameters. Eighty-two patients with a histologically confirmed musculoskeletal tumour were prospectively included in this study and, with ethics committee approval, underwent contrast-enhanced MR perfusion and T1 mapping. T1 value variations in viable tumour areas and in normal-appearing striated muscle were assessed. In 20 cases, normal muscle perfusion parameters were calculated using three different methods: signal based and gadolinium concentration based on fixed and variable T1 values. Tumour and normal muscle T1 values were significantly different (p = 0.0008). T1 value heterogeneity was higher in tumours than in normal muscle (variation of 19.8% versus 13%). The T1 estimation method had a considerable influence on the variability of perfusion parameters. Fixed T1 values yielded higher coefficients of variation than variable T1 values (mean 109.6 ± 41.8% and 58.3 ± 14.1% respectively). Area under the curve was the least variable parameter (36%). T1 values in musculoskeletal tumours are significantly different and more heterogeneous than normal muscle. Patient-specific T1 estimation is needed for direct inter-patient comparison of perfusion parameters. (orig.)

  5. Contrast-enhanced 3T MR Perfusion of Musculoskeletal Tumours: T1 Value Heterogeneity Assessment and Evaluation of the Influence of T1 Estimation Methods on Quantitative Parameters.

    Science.gov (United States)

    Gondim Teixeira, Pedro Augusto; Leplat, Christophe; Chen, Bailiang; De Verbizier, Jacques; Beaumont, Marine; Badr, Sammy; Cotten, Anne; Blum, Alain

    2017-12-01

    To evaluate intra-tumour and striated muscle T1 value heterogeneity and the influence of different methods of T1 estimation on the variability of quantitative perfusion parameters. Eighty-two patients with a histologically confirmed musculoskeletal tumour were prospectively included in this study and, with ethics committee approval, underwent contrast-enhanced MR perfusion and T1 mapping. T1 value variations in viable tumour areas and in normal-appearing striated muscle were assessed. In 20 cases, normal muscle perfusion parameters were calculated using three different methods: signal based and gadolinium concentration based on fixed and variable T1 values. Tumour and normal muscle T1 values were significantly different (p = 0.0008). T1 value heterogeneity was higher in tumours than in normal muscle (variation of 19.8% versus 13%). The T1 estimation method had a considerable influence on the variability of perfusion parameters. Fixed T1 values yielded higher coefficients of variation than variable T1 values (mean 109.6 ± 41.8% and 58.3 ± 14.1% respectively). Area under the curve was the least variable parameter (36%). T1 values in musculoskeletal tumours are significantly different and more heterogeneous than normal muscle. Patient-specific T1 estimation is needed for direct inter-patient comparison of perfusion parameters. • T1 value variation in musculoskeletal tumours is considerable. • T1 values in muscle and tumours are significantly different. • Patient-specific T1 estimation is needed for comparison of inter-patient perfusion parameters. • Technical variation is higher in permeability than semiquantitative perfusion parameters.

  6. Assessment of the zonal variation of perfusion parameters in the femoral head. A 3-T dynamic contrast-enhanced MRI pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Budzik, Jean-Francois [Lille Catholic University, Imaging Department, Lille Catholic Hospitals, Lille (France); Littoral Cote d' Opale University, Lille University, Lille (France); Lefebvre, Guillaume [University of Lille Nord de France, Musculoskeletal Imaging Department, Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHU Lille, Lille (France); Behal, Helene [University of Lille Nord de France, Biostatistics Department, Lille Regional University Hospital, Lille (France); Verclytte, Sebastien [Lille Catholic University, Imaging Department, Lille Catholic Hospitals, Lille (France); Hardouin, Pierre [Lille University, Littoral Cote d' Opale University, Lille (France); Teixeira, Pedro [Centre Hospitalier Universitaire de Nancy, Service d' Imagerie Guilloz, Hopital Central, Nancy (France); Cotten, Anne [Littoral Cote d' Opale University, Lille University, Lille (France); University of Lille Nord de France, Musculoskeletal Imaging Department, Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHU Lille, Lille (France)

    2018-02-15

    The objective was to describe MR perfusion characteristics of the femoral head, with a focus on the subchondral bone. This prospective monocentric study was approved by our local Ethics Committee. Written informed consent was obtained from all subjects. Dynamic contrast-enhanced MRI of the right hip was performed in 59 adults with suspected spondyloarthritis (32 women, 28 men). Mean age was 37.5 (±12.5) years. Regions of interest were drawn in the femoral head epiphysis, in the subchondral areas the most exposed to mechanical load (superolateral, anterosuperior, and posterior zones) and in areas less exposed to mechanical load (inferior subchondral zone and center of the femoral head). Semi-quantitative and pharmacokinetic parameters were calculated using the Tofts model. Statistical analysis was performed with a linear mixed model to compare the perfusion parameters in the different femoral head zones. Extravascular extracellular volume and area under the curve were lower in the superolateral zone than in the inferior zone (p = 0.0135 and p < 0.0001 respectively) and the central zone (p = 0.007 and p = 0.0134 respectively). Extravascular extracellular volume and rate constant were lower in the anterosuperior zone than in the inferior zones (p = 0.011 and p = 0.029). In the anterosuperior zone, extravascular extracellular volume was lower, and time to peak was higher than in the central zones (p = 0.0056 and p = 0.0013 respectively). No significant differences were found for any values between other paired zones. The perfusion of femoral head subchondral bone assessed with dynamic contrast-enhanced magnetic resonance imaging is not homogeneous: the areas exposed to more mechanical loading are less perfused. (orig.)

  7. A pilot trial on pulmonary emphysema quantification and perfusion mapping in a single-step using contrast-enhanced dual-energy computed tomography.

    Science.gov (United States)

    Lee, Choong Wook; Seo, Joon Beom; Lee, Youngjoo; Chae, Eun Jin; Kim, Namkug; Lee, Hyun Joo; Hwang, Hye Jeon; Lim, Chae-Hun

    2012-01-01

    To know whether contrast-enhanced dual-energy computed tomography angiography (DECTA) can be used for simultaneous assessment of emphysema quantification and regional perfusion evaluation. We assessed 27 patients who had pulmonary emphysema and no pulmonary embolism on visual assessment of CT images, among 584 consecutive patients who underwent DECTA for the evaluation of pulmonary embolism. Virtual noncontrast (VNC) images were generated by modifying the "Liver VNC" application in a dedicated workstation. Using in-house software, the low-attenuation area below 950HU (LAA950), the 15th percentile attenuation (15pctlVNC) and the mean lung attenuation (MeanVNC) were calculated. The "Lung PBV" application was used to assess perfusion, and the low-iodine area below 5HU (LIA5), the 15th percentile iodine (15pctlIodine), and the mean iodine value (MeanIodine) were calculated from iodine map images. The correlation between VNC parameters and pulmonary function test data (available in 22 patients) and the correlation between VNC and iodine map parameters (all included 27 patients) were assessed. Color-coded map of VNC image were compared with iodine map images for the evaluation of regional heterogeneity. We observed moderate correlations between LAA950 and predicted %FEV1 (rs = -0.47, P VNC images. We observed moderate correlations between quantitative parameters on VNC images and pulmonary function test data, and also observed moderate correlations between the severity of parenchymal destruction, as determined from VNC images, and perfusion status, as determined from iodine maps. Therefore, the contrast-enhanced DECTA can be used for the emphysema quantification and regional perfusion evaluation by using the VNC images and iodine map, simultaneously.

  8. Assessment of the zonal variation of perfusion parameters in the femoral head. A 3-T dynamic contrast-enhanced MRI pilot study

    International Nuclear Information System (INIS)

    Budzik, Jean-Francois; Lefebvre, Guillaume; Behal, Helene; Verclytte, Sebastien; Hardouin, Pierre; Teixeira, Pedro; Cotten, Anne

    2018-01-01

    The objective was to describe MR perfusion characteristics of the femoral head, with a focus on the subchondral bone. This prospective monocentric study was approved by our local Ethics Committee. Written informed consent was obtained from all subjects. Dynamic contrast-enhanced MRI of the right hip was performed in 59 adults with suspected spondyloarthritis (32 women, 28 men). Mean age was 37.5 (±12.5) years. Regions of interest were drawn in the femoral head epiphysis, in the subchondral areas the most exposed to mechanical load (superolateral, anterosuperior, and posterior zones) and in areas less exposed to mechanical load (inferior subchondral zone and center of the femoral head). Semi-quantitative and pharmacokinetic parameters were calculated using the Tofts model. Statistical analysis was performed with a linear mixed model to compare the perfusion parameters in the different femoral head zones. Extravascular extracellular volume and area under the curve were lower in the superolateral zone than in the inferior zone (p = 0.0135 and p < 0.0001 respectively) and the central zone (p = 0.007 and p = 0.0134 respectively). Extravascular extracellular volume and rate constant were lower in the anterosuperior zone than in the inferior zones (p = 0.011 and p = 0.029). In the anterosuperior zone, extravascular extracellular volume was lower, and time to peak was higher than in the central zones (p = 0.0056 and p = 0.0013 respectively). No significant differences were found for any values between other paired zones. The perfusion of femoral head subchondral bone assessed with dynamic contrast-enhanced magnetic resonance imaging is not homogeneous: the areas exposed to more mechanical loading are less perfused. (orig.)

  9. Investigating tumor perfusion by hyperpolarized (13) C MRI with comparison to conventional gadolinium contrast-enhanced MRI and pathology in orthotopic human GBM xenografts

    DEFF Research Database (Denmark)

    Park, Ilwoo; von Morze, Cornelius; Lupo, Janine M

    2016-01-01

    glioblastoma (GBM) model for the characterization of tumor perfusion and compared with standard Gd-based dynamic susceptibility contrast (DSC) MRI data and immunohistochemical analysis from resected brains. Distinct HMCP perfusion characteristics were observed within the GBM tumors compared with contralateral...... for tumor that exhibited high levels of hyperpolarized HMCP signal. The results from this study have demonstrated that hyperpolarized HMCP data can be used as an indicator of tumor perfusion in an orthotopic xenograft model for GBM. Magn Reson Med, 2016. © 2016 Wiley Periodicals, Inc....

  10. Perfusion maps of the whole liver based on high temporal and spatial resolution contrast-enhanced MRI (4D THRIVE): Feasibility and initial results in focal liver lesions

    International Nuclear Information System (INIS)

    Coenegrachts, Kenneth; Ghekiere, Johan; Denolin, Vincent; Gabriele, Beck; Herigault, Gwen; Haspeslagh, Marc; Daled, Peter; Bipat, Shandra; Stoker, Jaap; Rigauts, Hans

    2010-01-01

    Purpose: To prospectively evaluate a new imaging sequence (4D THRIVE) for whole liver perfusion in high temporal and spatial resolution. Feasibility of parametric mapping and its potential for characterizing focal liver lesions (FLLs) are investigated. Materials and methods: Fifteen patients suspected for colorectal liver metastases (LMs) were included. Parametric maps were evaluated qualitatively (ring-enhancement and lesion heterogeneity) and compared to three-phased contrast-enhanced MRI. Quantitative analysis was based on average perfusion values of entire FLLs. Reference standard comprised surgery with histopathology or follow-up imaging. Fisher's exact test was used for qualitative and Kruskal-Wallis test for quantitative analysis. Results: In total 29 LMs, 17 hemangiomas and 4 focal nodular hyperplasias were evaluated. FLLs could be differentiated by qualitative assessment of parametric maps respectively three-phased contrast-enhanced MRI (Fisher's p < 0.001 for comparisons between LMs and hemangiomas and LMs and FNHs for both ring-enhancement and lesion heterogeneity) rather than by quantitative analysis of parametric maps (Chi-square for Kep = 0.33 (p = 0.847) and Chi-square for Kel = 1.35 (p = 0.509)). Conclusion: This preliminary study shows potential of 4D THRIVE for whole liver imaging enabling calculation of parametric maps. Qualitative rather than quantitative analysis was accurate for differentiating malignant and benign FLLs.

  11. Measurement of extracellular volume and transit time heterogeneity using contrast-enhanced myocardial perfusion MRI in patients after acute myocardial infarction.

    Science.gov (United States)

    Kunze, Karl P; Rischpler, Christoph; Hayes, Carmel; Ibrahim, Tareq; Laugwitz, Karl-Ludwig; Haase, Axel; Schwaiger, Markus; Nekolla, Stephan G

    2017-06-01

    To assess the ability of dynamic contrast-enhanced myocardial perfusion MRI to measure extracellular volume (ECV) and to investigate the possibility of estimating capillary transit time heterogeneity (CTH) in patients after myocardial infarction and successful revascularization. Twenty-four perfusion data sets were acquired on a 3 Tesla positron emission tomography (PET)/MRI scanner. Three perfusion models of different complexity were implemented in a hierarchical fashion with an Akaike information criterion being used to determine the number of fit parameters supported by the data. Results were compared sector-wise to ECV from an equilibrium T 1 mapping method (modified look-locker inversion recovery (MOLLI)). ECV derived from the perfusion analysis correlated well with equilibrium measurements (R² = 0.76). Estimation of CTH was supported in 16% of sectors (mostly remote). Inclusion of a nonzero CTH parameter usually led to lower estimates of first-pass extraction and slightly higher estimates of blood volume and flow. Estimation of the capillary permeability-surface area product was feasible in 81% of sectors. Transit time heterogeneity has a measurable effect on the kinetic analysis of myocardial perfusion MRI data, and Gd-DTPA extravasation in the myocardium is usually not flow-limited in infarct-related pathology. Measurement of myocardial ECV using perfusion imaging could provide a scan-time efficient alternative to methods based on T 1 mapping. Magn Reson Med 77:2320-2330, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  12. Quantitative Myocardial Perfusion with Dynamic Contrast-Enhanced Imaging in MRI and CT: Theoretical Models and Current Implementation

    Directory of Open Access Journals (Sweden)

    G. J. Pelgrim

    2016-01-01

    Full Text Available Technological advances in magnetic resonance imaging (MRI and computed tomography (CT, including higher spatial and temporal resolution, have made the prospect of performing absolute myocardial perfusion quantification possible, previously only achievable with positron emission tomography (PET. This could facilitate integration of myocardial perfusion biomarkers into the current workup for coronary artery disease (CAD, as MRI and CT systems are more widely available than PET scanners. Cardiac PET scanning remains expensive and is restricted by the requirement of a nearby cyclotron. Clinical evidence is needed to demonstrate that MRI and CT have similar accuracy for myocardial perfusion quantification as PET. However, lack of standardization of acquisition protocols and tracer kinetic model selection complicates comparison between different studies and modalities. The aim of this overview is to provide insight into the different tracer kinetic models for quantitative myocardial perfusion analysis and to address typical implementation issues in MRI and CT. We compare different models based on their theoretical derivations and present the respective consequences for MRI and CT acquisition parameters, highlighting the interplay between tracer kinetic modeling and acquisition settings.

  13. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nielsen, Gitte; Hansen, Thomas Fritz; Dirks, Christina G

    2004-01-01

    with acute transmural myocardial infarction were studied using a Turbo-fast low angle shot (FLASH) MRI sequence to monitor the first pass of an extravascular contrast agent (CA), gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). Quantitation of perfusion, expressed as Ki (mL/100 g/minute), in five...

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  15. Differentiating between Central Nervous System Lymphoma and High-grade Glioma Using Dynamic Susceptibility Contrast and Dynamic Contrast-enhanced MR Imaging with Histogram Analysis.

    Science.gov (United States)

    Murayama, Kazuhiro; Nishiyama, Yuya; Hirose, Yuichi; Abe, Masato; Ohyu, Shigeharu; Ninomiya, Ayako; Fukuba, Takashi; Katada, Kazuhiro; Toyama, Hiroshi

    2018-01-10

    We evaluated the diagnostic performance of histogram analysis of data from a combination of dynamic susceptibility contrast (DSC)-MRI and dynamic contrast-enhanced (DCE)-MRI for quantitative differentiation between central nervous system lymphoma (CNSL) and high-grade glioma (HGG), with the aim of identifying useful perfusion parameters as objective radiological markers for differentiating between them. Eight lesions with CNSLs and 15 with HGGs who underwent MRI examination, including DCE and DSC-MRI, were enrolled in our retrospective study. DSC-MRI provides a corrected cerebral blood volume (cCBV), and DCE-MRI provides a volume transfer coefficient (K trans ) for transfer from plasma to the extravascular extracellular space. K trans and cCBV were measured from a round region-of-interest in the slice of maximum size on the contrast-enhanced lesion. The differences in t values between CNSL and HGG for determining the most appropriate percentile of K trans and cCBV were investigated. The differences in K trans , cCBV, and K trans /cCBV between CNSL and HGG were investigated using histogram analysis. Receiver operating characteristic (ROC) analysis of K trans , cCBV, and K trans /cCBV ratio was performed. The 30 th percentile (C30) in K trans and 80 th percentile (C80) in cCBV were the most appropriate percentiles for distinguishing between CNSL and HGG from the differences in t values. CNSL showed significantly lower C80 cCBV, significantly higher C30 K trans , and significantly higher C30 K trans /C80 cCBV than those of HGG. In ROC analysis, C30 K trans /C80 cCBV had the best discriminative value for differentiating between CNSL and HGG as compared to C30 K trans or C80 cCBV. The combination of K trans by DCE-MRI and cCBV by DSC-MRI was found to reveal the characteristics of vascularity and permeability of a lesion more precisely than either K trans or cCBV alone. Histogram analysis of these vascular microenvironments enabled quantitative differentiation between

  16. Evaluation of femoral perfusion in a rabbit model of steroid-induced osteonecrosis by dynamic contrast-enhanced MRI with a high magnetic field MRI system.

    Science.gov (United States)

    Hayashi, Shigeki; Fujioka, Mikihiro; Ikoma, Kazuya; Saito, Masazumi; Ueshima, Keiichiro; Ishida, Masashi; Kuribayashi, Masaaki; Ikegami, Akira; Mazda, Osam; Kubo, Toshikazu

    2015-04-01

    To evaluate perfusion during the early phase after steroid administration in vivo using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with a high magnetic field MRI system. The main pathogenesis of steroid-induced osteonecrosis is considered to be ischemia. A single dose of methylprednisolone (MPSL) was injected into nine rabbits. DCE-MRI was performed for these rabbits before MPSL administration and 1, 5, 10, and 14 days after administration. Time-signal intensity curves were created for each femur based on the signal intensity to evaluate perfusion. Enhancement ratio (ER), initial slope (IS), and area under the curve (AUC) were calculated and the value before MPSL administration and the minimal value after administration were compared statistically. ER, IS, and AUC values after MPSL administration significantly decreased (P < 0.05, P < 0.01, and P < 0.01, respectively). All of them decreased by the 5th day in 56% of the femora and by the 14th day in 83%, and some femora even showed a decrease from the 1st day. In this study, decreased perfusion in the femora after steroid administration was proven. Additionally, we could show that it occurred from the early days after steroid administration. © 2014 Wiley Periodicals, Inc.

  17. Use of Contrast-Enhanced Ultrasound to Study Relationship between Serum Uric Acid and Renal Microvascular Perfusion in Diabetic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Ling Wang

    2015-01-01

    Full Text Available Purpose. To investigate the relationship between uric acid and renal microvascular perfusion in diabetic kidney disease (DKD using contrast-enhanced ultrasound (CEUS method. Materials and Methods. 79 DKD patients and 26 healthy volunteers were enrolled. Renal function and urine protein markers were tested. DKD patients were subdivided into two groups including a normal serum uric acid (SUA group and a high SUA group. Contrast-enhanced ultrasound (CEUS was performed, and low acoustic power contrast-specific imaging was used for quantitative analysis. Results. Normal controls (NCs had the highest levels of AUC, AUC1, and AUC2. Compared to the normal SUA DKD group, high SUA DKD patients had significantly higher IMAX, AUC, and AUC1 (P<0.05. DKD patients with low urinary uric acid (UUA excretion had significantly higher AUC2 compared to DKD patients with normal UUA (P<0.05. Conclusion. Hyperuricemia in DKD patients was associated with a renal ultrasound image suggestive of microvascular hyperperfusion. The CEUS parameter AUC1 holds promise as an indicator for renal microvascular hyperperfusion, while AUC2 might be a useful indicator of declining glomerular filtration rate in DKD patients with decreased excretion of uric acid.

  18. Prevalence of first-pass myocardial perfusion defects detected by contrast-enhanced dual-source CT in patients with non-ST segment elevation acute coronary syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Schepis, Tiziano; Achenbach, Stephan; Marwan, Mohamed; Muschiol, Gerd; Ropers, Dieter; Daniel, Werner G.; Pflederer, Tobias [University of Erlangen, Department of Internal Medicine 2 (Cardiology), Erlangen (Germany)

    2010-07-15

    To investigate the prevalence and diagnostic value of first-pass myocardial perfusion defects (PD) visualised by contrast-enhanced multidetector computed tomography (MDCT) in patients admitted for a first acute coronary syndrome (ACS). Thirty-eight patients with non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA) and scheduled for percutaneous coronary intervention underwent dual-source CT immediately before catheterisation. CT images were analysed for the presence of any PD by using a 17-segment model. Results were compared with peak cardiac troponin-I (cTnI) and angiography findings. PD were seen in 21 of the 24 patients with NSTEMI (median peak cTnI level 7.07 ng/mL; range 0.72-37.07 ng/mL) and in 2 of 14 patients with UA. PD corresponded with the territory of the infarct-related artery in 20 out of 22 patients. In a patient-based analysis, sensitivity, specificity, negative and positive predictive values of any PD for predicting NSTEMI were 88%, 86%, 80% and 91%. Per culprit artery, the respective values were 86%, 75%, 80% and 83%. In patients with non-ST segment elevation ACS, first-pass myocardial PD in contrast-enhanced MDCT correlate closely with the presence of myocardial necrosis, as determined by increases in cTnI levels. (orig.)

  19. Characterization of Metabolic, Diffusion, and Perfusion Properties in GBM: Contrast-Enhancing versus Non-Enhancing Tumor.

    Science.gov (United States)

    Autry, Adam; Phillips, Joanna J; Maleschlijski, Stojan; Roy, Ritu; Molinaro, Annette M; Chang, Susan M; Cha, Soonmee; Lupo, Janine M; Nelson, Sarah J

    2017-12-01

    Although the contrast-enhancing (CE) lesion on T 1 -weighted MR images is widely used as a surrogate for glioblastoma (GBM), there are also non-enhancing regions of infiltrative tumor within the T 2 -weighted lesion, which elude radiologic detection. Because non-enhancing GBM (Enh-) challenges clinical patient management as latent disease, this study sought to characterize ex vivo metabolic profiles from Enh- and CE GBM (Enh+) samples, alongside histological and in vivo MR parameters, to assist in defining criteria for estimating total tumor burden. Fifty-six patients with newly diagnosed GBM received a multi-parametric pre-surgical MR examination. Targets for obtaining image-guided tissue samples were defined based on in vivo parameters that were suspicious for tumor. The actual location from where tissue samples were obtained was recorded, and half of each sample was analyzed for histopathology while the other half was scanned using HR-MAS spectroscopy. The Enh+ and Enh- tumor samples demonstrated comparable mitotic activity, but also significant heterogeneity in microvascular morphology. Ex vivo spectroscopic parameters indicated similar levels of total choline and N-acetylaspartate between these contrast-based radiographic subtypes of GBM, and characteristic differences in the levels of myo-inositol, creatine/phosphocreatine, and phosphoethanolamine. Analysis of in vivo parameters at the sample locations were consistent with histological and ex vivo metabolic data. The similarity between ex vivo levels of choline and NAA, and between in vivo levels of choline, NAA and nADC in Enh+ and Enh- tumor, indicate that these parameters can be used in defining non-invasive metrics of total tumor burden for patients with GBM. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Characterization of Metabolic, Diffusion, and Perfusion Properties in GBM: Contrast-Enhancing versus Non-Enhancing Tumor

    Directory of Open Access Journals (Sweden)

    Adam Autry

    2017-12-01

    Full Text Available BACKGROUND: Although the contrast-enhancing (CE lesion on T1-weighted MR images is widely used as a surrogate for glioblastoma (GBM, there are also non-enhancing regions of infiltrative tumor within the T2-weighted lesion, which elude radiologic detection. Because non-enhancing GBM (Enh− challenges clinical patient management as latent disease, this study sought to characterize ex vivo metabolic profiles from Enh− and CE GBM (Enh+ samples, alongside histological and in vivo MR parameters, to assist in defining criteria for estimating total tumor burden. Methods: Fifty-six patients with newly diagnosed GBM received a multi-parametric pre-surgical MR examination. Targets for obtaining image-guided tissue samples were defined based on in vivo parameters that were suspicious for tumor. The actual location from where tissue samples were obtained was recorded, and half of each sample was analyzed for histopathology while the other half was scanned using HR-MAS spectroscopy. Results: The Enh+ and Enh− tumor samples demonstrated comparable mitotic activity, but also significant heterogeneity in microvascular morphology. Ex vivo spectroscopic parameters indicated similar levels of total choline and N-acetylaspartate between these contrast-based radiographic subtypes of GBM, and characteristic differences in the levels of myo-inositol, creatine/phosphocreatine, and phosphoethanolamine. Analysis of in vivo parameters at the sample locations were consistent with histological and ex vivo metabolic data. CONCLUSIONS: The similarity between ex vivo levels of choline and NAA, and between in vivo levels of choline, NAA and nADC in Enh+ and Enh− tumor, indicate that these parameters can be used in defining non-invasive metrics of total tumor burden for patients with GBM.

  1. Perfusion of subchondral bone marrow in knee osteoarthritis: A dynamic contrast-enhanced magnetic resonance imaging preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Budzik, Jean-François, E-mail: Budzik.jean-francois@ghicl.net [Lille Catholic Hospitals, Imaging Department, Lille Catholic University, Lille (France); PMOI Physiopathology of Inflammatory Bone Diseases, EA 4490, Lille (France); Ding, Juliette, E-mail: Ding.juliette@gmail.com [Lille Catholic Hospitals, Imaging Department, Lille Catholic University, Lille (France); Norberciak, Laurène, E-mail: Norberciak.Laurene@ghicl.net [Lille Catholic Hospitals, Biostatistics Department, Lille Catholic University, Lille (France); Pascart, Tristan, E-mail: Pascart.tristan@ghicl.net [Lille Catholic Hospitals, Rheumatology Department, Lille Catholic University, Lille (France); Toumi, Hechmi, E-mail: hechmi.toumi@univ-orleans.fr [EA4708 I3MTO, Orleans Regional Hospital, University of Orleans, Orleans (France); Verclytte, Sébastien, E-mail: Verclytte.Sebastien@ghicl.net [Lille Catholic Hospitals, Imaging Department, Lille Catholic University, Lille (France); Coursier, Raphaël, E-mail: Coursier.Raphael@ghicl.net [Lille Catholic Hospitals, Orthopaedic Surgery Department, Lille Catholic University, Lille (France)

    2017-03-15

    The role of inflammation in the pathogenesis of osteoarthritis is being given major interest, and inflammation is closely linked with vascularization. It was recently demonstrated that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could identify the subchondral bone marrow vascularization changes occurring in osteoarthritis in animals. These changes appeared before cartilage lesions were visible and were correlated with osteoarthritis severity. Thus the opportunity to obtain an objective assessment of bone vascularization in non-invasive conditions in humans might help better understanding osteoarthritis pathophysiology and finding new biomarkers. We hypothesized that, as in animals, DCE-MRI has the ability to identify subchondral bone marrow vascularization changes in human osteoarthritis. We performed knee MRI in 19 patients with advanced knee osteoarthritis. We assessed subchondral bone marrow vascularization in medial and lateral femorotibial compartments with DCE-MRI and graded osteoarthritis lesions on MR images. Statistical analysis assessed intra- and inter-observer agreement, compared DCE-MRI values between the different subchondral zones, and sought for an influence of age, sex, body mass index, and osteoarthritis garde on these values. The intra- and inter-observer agreement for DCE-MRI values were excellent. These values were significantly higher in the femorotibial compartment the most affected by osteoarthritis, both in femur and tibia (p < 0.0001) and were significantly and positively correlated with cartilage lesions (p = 0.02) and bone marrow oedema grade (p < 0.0001) after adjustment. We concluded that, as in animals, subchondral bone marrow vascularization changes assessed with DCE-MRI were correlated with osteoarthritis severity in humans.

  2. Perfusion of subchondral bone marrow in knee osteoarthritis: A dynamic contrast-enhanced magnetic resonance imaging preliminary study

    International Nuclear Information System (INIS)

    Budzik, Jean-François; Ding, Juliette; Norberciak, Laurène; Pascart, Tristan; Toumi, Hechmi; Verclytte, Sébastien; Coursier, Raphaël

    2017-01-01

    The role of inflammation in the pathogenesis of osteoarthritis is being given major interest, and inflammation is closely linked with vascularization. It was recently demonstrated that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could identify the subchondral bone marrow vascularization changes occurring in osteoarthritis in animals. These changes appeared before cartilage lesions were visible and were correlated with osteoarthritis severity. Thus the opportunity to obtain an objective assessment of bone vascularization in non-invasive conditions in humans might help better understanding osteoarthritis pathophysiology and finding new biomarkers. We hypothesized that, as in animals, DCE-MRI has the ability to identify subchondral bone marrow vascularization changes in human osteoarthritis. We performed knee MRI in 19 patients with advanced knee osteoarthritis. We assessed subchondral bone marrow vascularization in medial and lateral femorotibial compartments with DCE-MRI and graded osteoarthritis lesions on MR images. Statistical analysis assessed intra- and inter-observer agreement, compared DCE-MRI values between the different subchondral zones, and sought for an influence of age, sex, body mass index, and osteoarthritis garde on these values. The intra- and inter-observer agreement for DCE-MRI values were excellent. These values were significantly higher in the femorotibial compartment the most affected by osteoarthritis, both in femur and tibia (p < 0.0001) and were significantly and positively correlated with cartilage lesions (p = 0.02) and bone marrow oedema grade (p < 0.0001) after adjustment. We concluded that, as in animals, subchondral bone marrow vascularization changes assessed with DCE-MRI were correlated with osteoarthritis severity in humans.

  3. Validation of Fourier decomposition MRI with dynamic contrast-enhanced MRI using visual and automated scoring of pulmonary perfusion in young cystic fibrosis patients

    International Nuclear Information System (INIS)

    Bauman, Grzegorz; Puderbach, Michael; Heimann, Tobias; Kopp-Schneider, Annette; Fritzsching, Eva; Mall, Marcus A.; Eichinger, Monika

    2013-01-01

    Purpose: To validate Fourier decomposition (FD) magnetic resonance (MR) imaging in cystic fibrosis (CF) patients with dynamic contrast-enhanced (DCE) MR imaging. Materials and methods: Thirty-four CF patients (median age 4.08 years; range 0.16–30) were examined on a 1.5-T MR imager. For FD MR imaging, sets of lung images were acquired using an untriggered two-dimensional balanced steady-state free precession sequence. Perfusion-weighted images were obtained after correction of the breathing displacement and Fourier analysis of the cardiac frequency from the time-resolved data sets. DCE data sets were acquired with a three-dimensional gradient echo sequence. The FD and DCE images were visually assessed for perfusion defects by two readers independently (R1, R2) using a field based scoring system (0–12). Software was used for perfusion impairment evaluation (R3) of segmented lung images using an automated threshold. Both imaging and evaluation methods were compared for agreement and tested for concordance between FD and DCE imaging. Results: Good or acceptable intra-reader agreement was found between FD and DCE for visual and automated scoring: R1 upper and lower limits of agreement (ULA, LLA): 2.72, −2.5; R2: ULA, LLA: ±2.5; R3: ULA: 1.5, LLA: −2. A high concordance was found between visual and automated scoring (FD: 70–80%, DCE: 73–84%). Conclusions: FD MR imaging provides equivalent diagnostic information to DCE MR imaging in CF patients. Automated assessment of regional perfusion defects using FD and DCE MR imaging is comparable to visual scoring but allows for percentage-based analysis

  4. Multimodality functional imaging of spontaneous canine tumors using 64Cu-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

    International Nuclear Information System (INIS)

    Hansen, Anders E.; Kristensen, Annemarie T.; Law, Ian; McEvoy, Fintan J.; Kjær, Andreas; Engelholm, Svend A.

    2012-01-01

    Purpose: To compare the distribution and uptake of the hypoxia tracer 64 Cu-diacetyl-bis(N 4 -methylthiosemicarbazone) ( 64 Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition 64 Cu-ATSM distribution over time was evaluated. Methods and materials: Nine spontaneous cancer-bearing dogs were prospectively enrolled. FDG (1 h pi.) and 64 Cu-ATSM (3 and 24 h pi.) PET/CT were performed over three consecutive days. DCE-pCT was performed on day 2. Tumor uptake of FDG and 64 Cu-ATSM was assessed semi-quantitatively and the distribution of FDG, 64 Cu-ATSM and CT perfusion parameters correlated. Results: 64 Cu-ATSM distribution on scans performed 24 h apart displayed moderate to strong correlation; however, temporal changes were observed. The spatial distribution pattern of 64 Cu-ATSM between scans was moderately to strongly positively correlated to FDG, whereas the correlation of CT perfusion parameters to FDG and to 64 Cu-ATSM yielded more varying results. Conclusions: 64 Cu-ATSM uptake was positively correlated to FDG. 64 Cu-ATSM was found to be relatively stable between PET scans performed at different time points, important temporal changes were however observed in hypo-perfused regions. These findings potentially indicate that prolonged uptake periods for 64 Cu-ATSM imaging may be needed. Although a moderate to strong correlation between 64 Cu-ATSM and FDG PET/CT is observed, the two tracers provide different biological information with an overlapping spatial distribution.

  5. Validation of Fourier decomposition MRI with dynamic contrast-enhanced MRI using visual and automated scoring of pulmonary perfusion in young cystic fibrosis patients

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, Grzegorz, E-mail: g.bauman@dkfz.de [German Cancer Research Center, Division of Medical Physics in Radiology, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany); Puderbach, Michael, E-mail: m.puderbach@dkfz.de [Chest Clinics at the University of Heidelberg, Clinics for Interventional and Diagnostic Radiology, Amalienstr. 5, 69126 Heidelberg (Germany); Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (Germany); Heimann, Tobias, E-mail: t.heimann@dkfz.de [German Cancer Research Center, Division of Medical and Biological Informatics, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany); Kopp-Schneider, Annette, E-mail: kopp@dkfz.de [German Cancer Research Center, Division of Biostatistics, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany); Fritzsching, Eva, E-mail: eva.fritzsching@med.uni-heidelberg.de [University Hospital Heidelberg, Department of Translational Pulmonology and Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Im Neuenheimer Feld 430, Heidelberg (Germany); Mall, Marcus A., E-mail: marcus.mall@med.uni-heidelberg.de [Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (Germany); University Hospital Heidelberg, Department of Translational Pulmonology and Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Im Neuenheimer Feld 430, Heidelberg (Germany); Eichinger, Monika, E-mail: m.eichinger@dkfz.de [Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (Germany); German Cancer Research Center, Division of Radiology, Im Neuenheimer Feld 223, 69120 Heidelberg (Germany)

    2013-12-01

    Purpose: To validate Fourier decomposition (FD) magnetic resonance (MR) imaging in cystic fibrosis (CF) patients with dynamic contrast-enhanced (DCE) MR imaging. Materials and methods: Thirty-four CF patients (median age 4.08 years; range 0.16–30) were examined on a 1.5-T MR imager. For FD MR imaging, sets of lung images were acquired using an untriggered two-dimensional balanced steady-state free precession sequence. Perfusion-weighted images were obtained after correction of the breathing displacement and Fourier analysis of the cardiac frequency from the time-resolved data sets. DCE data sets were acquired with a three-dimensional gradient echo sequence. The FD and DCE images were visually assessed for perfusion defects by two readers independently (R1, R2) using a field based scoring system (0–12). Software was used for perfusion impairment evaluation (R3) of segmented lung images using an automated threshold. Both imaging and evaluation methods were compared for agreement and tested for concordance between FD and DCE imaging. Results: Good or acceptable intra-reader agreement was found between FD and DCE for visual and automated scoring: R1 upper and lower limits of agreement (ULA, LLA): 2.72, −2.5; R2: ULA, LLA: ±2.5; R3: ULA: 1.5, LLA: −2. A high concordance was found between visual and automated scoring (FD: 70–80%, DCE: 73–84%). Conclusions: FD MR imaging provides equivalent diagnostic information to DCE MR imaging in CF patients. Automated assessment of regional perfusion defects using FD and DCE MR imaging is comparable to visual scoring but allows for percentage-based analysis.

  6. Comparison of transient arterial occlusion and muscle exercise provocation for assessment of perfusion reserve in skeletal muscle with real-time contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Krix, Martin; Krakowski-Roosen, Holger; Armarteifio, Erick; Fuerstenberger, Susanne; Delorme, Stefan; Kauczor, Hans-Ulrich; Weber, Marc-Andre

    2011-01-01

    Objective: Contrast-enhanced ultrasound (CEUS) is able to quantify muscle perfusion and changes in perfusion due to muscle exercise in real-time. However, reliable measurement of standardized muscle exercise is difficult to perform in clinical examinations. We compared perfusion reserve assessed by CEUS after transient arterial occlusion and exercise to find the most suitable measurement for clinical application. Methods: Contrast pulse sequencing (7 MHz) during continuous IV infusion of SonoVue (4.8 mL/300 s) was used in 8 healthy volunteers to monitor muscle perfusion of the gastrocnemius muscle during transient (1 min) arterial occlusion produced by a thigh cuff of a venous occlusion plethysmograph. Isometric muscle exercise (50% of individual maximum strength for 20 s) was subsequently performed during the same examination, and several CEUS parameters obtained from ultrasound-signal-intensity-time curves and its calculation errors were compared. Results: The mean maximum local blood volume after occlusion was 13.9 [∼mL] (range, 4.5-28.8 [∼mL]), and similar values were measured after sub-maximum exercise 13.8 [∼mL], (range, 4.6-22.2 [∼mL]. The areas under the curve during reperfusion vs. recovery were also similar (515.2 ± 257.5 compared to 482.2 ± 187.5 [∼mL s]) with a strong correlation (r = 0.65), as were the times to maximum (15.3 s vs. 15.9 s), with a significantly smaller variation for the occlusion method (±2.1 s vs. ±9.0 s, p = 0.03). The mean errors for all calculated CEUS parameters were lower for the occlusion method than for the exercise test. Conclusions: CEUS muscle perfusion measurements can be easily performed after transient arterial occlusion. It delivers data which are comparable to CEUS measurements after muscle exercise but with a higher robustness. This method can be easily applied in clinical examination of patients with e.g. PAOD or diabetic microvessel diseases to assess perfusion reserve.

  7. Validation of Perfusion Quantification with 3D Gradient Echo Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using a Blood Pool Contrast Agent in Skeletal Swine Muscle.

    Directory of Open Access Journals (Sweden)

    Stefan Hindel

    Full Text Available The purpose of our study was to validate perfusion quantification in a low-perfused tissue by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI with shared k-space sampling using a blood pool contrast agent. Perfusion measurements were performed in a total of seven female pigs. An ultrasonic Doppler probe was attached to the right femoral artery to determine total flow in the hind leg musculature. The femoral artery was catheterized for continuous local administration of adenosine to increase blood flow up to four times the baseline level. Three different stable perfusion levels were induced. The MR protocol included a 3D gradient-echo sequence with a temporal resolution of approximately 1.5 seconds. Before each dynamic sequence, static MR images were acquired with flip angles of 5°, 10°, 20°, and 30°. Both static and dynamic images were used to generate relaxation rate and baseline magnetization maps with a flip angle method. 0.1 mL/kg body weight of blood pool contrast medium was injected via a central venous catheter at a flow rate of 5 mL/s. The right hind leg was segmented in 3D into medial, cranial, lateral, and pelvic thigh muscles, lower leg, bones, skin, and fat. The arterial input function (AIF was measured in the aorta. Perfusion of the different anatomic regions was calculated using a one- and a two-compartment model with delay- and dispersion-corrected AIFs. The F-test for model comparison was used to decide whether to use the results of the one- or two-compartment model fit. Total flow was calculated by integrating volume-weighted perfusion values over the whole measured region. The resulting values of delay, dispersion, blood volume, mean transit time, and flow were all in physiologically and physically reasonable ranges. In 107 of 160 ROIs, the blood signal was separated, using a two-compartment model, into a capillary and an arteriolar signal contribution, decided by the F-test. Overall flow in hind leg muscles

  8. A comparison of perfusion computed tomography and contrast enhanced computed tomography on radiation target volume delineation using rabbit VX2 brain tumor model

    International Nuclear Information System (INIS)

    Sun Changjin; Luo Yunxiu; Yu Jinming; Lu Haibo; Li Chao; Zhang Dekang; Huang Jianming; Wang Jie; Lang Jinyi

    2010-01-01

    Objective: To compare the accuracy of blood volume perfusion imaging (perfusion CT)with contrast enhanced 64-slice spiral computed tomography (CECT) in the evaluation of gross tumor volume (GTV) and clinical target volume (CTV) using rabbits with VX2 brain tumor. Methods: Perfusion CT and CECT were performed in 20 rabbits with VX2 brain tumor. The GTV and CTV calculated with the maximal and minimal diameter of each tumor in the blood volume (BV) maps and CECT were measured and compared to those in pathological specimens. Results: The mean value of the maximal and minimal diameter of GTV was (8.19 ± 2.29) mm and (4.83 ± 1.31) mm in pathological specimens, (11.98 ±3.29) mm and (7.03±1.82) mm in BV maps, while (6.36±3.85) mm and (3.17±1.93) mm in CECT images, which were significantly different (pathological specimen vs. BV map, t = 7.17, P =0.000;pathological specimen vs. CECT, t = 8.37, P = 0.000, respectively). The mean value of the maximal and minimal diameter of CTV in pathologic specimens was (12.87 ± 3.74) mm and (7.71 ± 2.15) mm, which was significantly different from that of GTV and CTV in CECT (t = - 3. 18, P = 0. 005 and t = - 4.24, P =0.000; t= -11.59,P=0.000 and t= -9.39, P=0.000), while similar with that of GTV in BV maps (t = - 1.95,P = 0. 067; t = - 2. 06, P = 0. 054). For CECT, the margin from GTV to CTV was 81.83% ±40.33% for the maximal diameter and 276.73% ± 131.46% for the minimal. While for BV maps, the margin was 7.93% ± 17. 84% and 12.52% ± 27. 83%, which was significant different from that for CECT images (t=7.36, P=0. 000 and t= -8.78, P=0.000). Conclusions: Compared with CECT, the BV map from 64-slice spiral CT perfusion imaging might have higher accuracy in target volume delineation for brain tumor. (authors)

  9. Influence of amplitude-related perfusion parameters in the parotid glands by non-fat-saturated dynamic contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Chiu, Su-Chin; Cheng, Cheng-Chieh; Chang, Hing-Chiu; Chung, Hsiao-Wen; Chiu, Hui-Chu; Liu, Yi-Jui; Hsu, Hsian-He; Juan, Chun-Jung

    2016-01-01

    Purpose: To verify whether quantification of parotid perfusion is affected by fat signals on non-fat-saturated (NFS) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and whether the influence of fat is reduced with fat saturation (FS). Methods: This study consisted of three parts. First, a retrospective study analyzed DCE-MRI data previously acquired on different patients using NFS (n = 18) or FS (n = 18) scans. Second, a phantom study simulated the signal enhancements in the presence of gadolinium contrast agent at six concentrations and three fat contents. Finally, a prospective study recruited nine healthy volunteers to investigate the influence of fat suppression on perfusion quantification on the same subjects. Parotid perfusion parameters were derived from NFS and FS DCE-MRI data using both pharmacokinetic model analysis and semiquantitative parametric analysis. T tests and linear regression analysis were used for statistical analysis with correction for multiple comparisons. Results: NFS scans showed lower amplitude-related parameters, including parameter A, peak enhancement (PE), and slope than FS scans in the patients (all with P < 0.0167). The relative signal enhancement in the phantoms was proportional to the dose of contrast agent and was lower in NFS scans than in FS scans. The volunteer study showed lower parameter A (6.75 ± 2.38 a.u.), PE (42.12% ± 14.87%), and slope (1.43% ± 0.54% s"−"1) in NFS scans as compared to 17.63 ± 8.56 a.u., 104.22% ± 25.15%, and 9.68% ± 1.67% s"−"1, respectively, in FS scans (all with P < 0.005). These amplitude-related parameters were negatively associated with the fat content in NFS scans only (all with P < 0.05). Conclusions: On NFS DCE-MRI, quantification of parotid perfusion is adversely affected by the presence of fat signals for all amplitude-related parameters. The influence could be reduced on FS scans.

  10. Influence of amplitude-related perfusion parameters in the parotid glands by non-fat-saturated dynamic contrast-enhanced magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Su-Chin [Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei 106, Taiwan, Republic of China and Department of Radiology, Tri-Service General Hospital, Taipei 114, Taiwan (China); Cheng, Cheng-Chieh [Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115 (United States); Chang, Hing-Chiu [Department of Diagnostic Radiology, The University of Hong Kong (Hong Kong); Chung, Hsiao-Wen [Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei 106, Taiwan (China); Department of Radiology, Tri-Service General Hospital, Taipei 114, Taiwan (China); Department of Radiology, National Defense Medical Center, Taipei 114, Taiwan (China); Chiu, Hui-Chu [Ph.D. Program of Technology Management, Chung Hua University, Hsinchu 300, Taiwan (China); Liu, Yi-Jui [Department of Automatic Control Engineering, Feng-Chia University, Taichung 407, Taiwan (China); Hsu, Hsian-He; Juan, Chun-Jung, E-mail: peterjuancj@yahoo.com.tw [Department of Radiology, Tri-Service General Hospital, Taipei 114, Taiwan and Department of Radiology, National Defense Medical Center, Taipei 114, Taiwan (China)

    2016-04-15

    Purpose: To verify whether quantification of parotid perfusion is affected by fat signals on non-fat-saturated (NFS) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and whether the influence of fat is reduced with fat saturation (FS). Methods: This study consisted of three parts. First, a retrospective study analyzed DCE-MRI data previously acquired on different patients using NFS (n = 18) or FS (n = 18) scans. Second, a phantom study simulated the signal enhancements in the presence of gadolinium contrast agent at six concentrations and three fat contents. Finally, a prospective study recruited nine healthy volunteers to investigate the influence of fat suppression on perfusion quantification on the same subjects. Parotid perfusion parameters were derived from NFS and FS DCE-MRI data using both pharmacokinetic model analysis and semiquantitative parametric analysis. T tests and linear regression analysis were used for statistical analysis with correction for multiple comparisons. Results: NFS scans showed lower amplitude-related parameters, including parameter A, peak enhancement (PE), and slope than FS scans in the patients (all with P < 0.0167). The relative signal enhancement in the phantoms was proportional to the dose of contrast agent and was lower in NFS scans than in FS scans. The volunteer study showed lower parameter A (6.75 ± 2.38 a.u.), PE (42.12% ± 14.87%), and slope (1.43% ± 0.54% s{sup −1}) in NFS scans as compared to 17.63 ± 8.56 a.u., 104.22% ± 25.15%, and 9.68% ± 1.67% s{sup −1}, respectively, in FS scans (all with P < 0.005). These amplitude-related parameters were negatively associated with the fat content in NFS scans only (all with P < 0.05). Conclusions: On NFS DCE-MRI, quantification of parotid perfusion is adversely affected by the presence of fat signals for all amplitude-related parameters. The influence could be reduced on FS scans.

  11. Comparison of semi-quantitative and quantitative dynamic contrast-enhanced MRI evaluations of vertebral marrow perfusion in a rat osteoporosis model.

    Science.gov (United States)

    Zhu, Jingqi; Xiong, Zuogang; Zhang, Jiulong; Qiu, Yuyou; Hua, Ting; Tang, Guangyu

    2017-11-14

    This study aims to investigate the technical feasibility of semi-quantitative and quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in the assessment of longitudinal changes of marrow perfusion in a rat osteoporosis model, using bone mineral density (BMD) measured by micro-computed tomography (micro-CT) and histopathology as the gold standards. Fifty rats were randomly assigned to the control group (n=25) and ovariectomy (OVX) group whose bilateral ovaries were excised (n=25). Semi-quantitative and quantitative DCE-MRI, micro-CT, and histopathological examinations were performed on lumbar vertebrae at baseline and 3, 6, 9, and 12 weeks after operation. The differences between the two groups in terms of semi-quantitative DCE-MRI parameter (maximum enhancement, E max ), quantitative DCE-MRI parameters (volume transfer constant, K trans ; interstitial volume, V e ; and efflux rate constant, K ep ), micro-CT parameter (BMD), and histopathological parameter (microvessel density, MVD) were compared at each of the time points using an independent-sample t test. The differences in these parameters between baseline and other time points in each group were assessed via Bonferroni's multiple comparison test. A Pearson correlation analysis was applied to assess the relationships between DCE-MRI, micro-CT, and histopathological parameters. In the OVX group, the E max values decreased significantly compared with those of the control group at weeks 6 and 9 (p=0.003 and 0.004, respectively). The K trans values decreased significantly compared with those of the control group from week 3 (pquantitative DCE-MRI, the quantitative DCE-MRI parameter K trans is a more sensitive and accurate index for detecting early reduced perfusion in osteoporotic bone.

  12. Quantitative Analysis of First-Pass Contrast-Enhanced Myocardial Perfusion Multidetector CT Using a Patlak Plot Method and Extraction Fraction Correction During Adenosine Stress

    Science.gov (United States)

    Ichihara, Takashi; George, Richard T.; Silva, Caterina; Lima, Joao A. C.; Lardo, Albert C.

    2011-02-01

    The purpose of this study was to develop a quantitative method for myocardial blood flow (MBF) measurement that can be used to derive accurate myocardial perfusion measurements from dynamic multidetector computed tomography (MDCT) images by using a compartment model for calculating the first-order transfer constant (K1) with correction for the capillary transit extraction fraction (E). Six canine models of left anterior descending (LAD) artery stenosis were prepared and underwent first-pass contrast-enhanced MDCT perfusion imaging during adenosine infusion (0.14-0.21 mg/kg/min). K1 , which is the first-order transfer constant from left ventricular (LV) blood to myocardium, was measured using the Patlak plot method applied to time-attenuation curve data of the LV blood pool and myocardium. The results were compared against microsphere MBF measurements, and the extraction fraction of contrast agent was calculated. K1 is related to the regional MBF as K1=EF, E=(1-exp(-PS/F)), where PS is the permeability-surface area product and F is myocardial flow. Based on the above relationship, a look-up table from K1 to MBF can be generated and Patlak plot-derived K1 values can be converted to the calculated MBF. The calculated MBF and microsphere MBF showed a strong linear association. The extraction fraction in dogs as a function of flow (F) was E=(1-exp(-(0.2532F+0.7871)/F)) . Regional MBF can be measured accurately using the Patlak plot method based on a compartment model and look-up table with extraction fraction correction from K1 to MBF.

  13. Early perfusion changes within 1 week of systemic treatment measured by dynamic contrast-enhanced MRI may predict survival in patients with advanced hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Bang-Bin; Yu, Chih-Wei; Liang, Po-Chin [National Taiwan University College of Medicine and Hospital, Department of Medical Imaging and Radiology, Taipei City (China); Hsu, Chao-Yu [National Taiwan University College of Medicine and Hospital, Department of Medical Imaging and Radiology, Taipei City (China); Taipei Hospital, Ministry of Health and Welfare, Department of Radiology, New Taipei City (China); Hsu, Chiun; Hsu, Chih-Hung; Cheng, Ann-Lii [National Taiwan University College of Medicine and Hospital, Department of Oncology, Taipei City (China); Shih, Tiffany Ting-Fang [National Taiwan University College of Medicine and Hospital, Department of Medical Imaging and Radiology, Taipei City (China); Taipei City Hospital, Department of Medical Imaging, Taipei City (China); National Taiwan University Hospital, Department of Medical Imaging, Taipei (China)

    2017-07-15

    To correlate early changes in the parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) within 1 week of systemic therapy with overall survival (OS) in patients with advanced hepatocellular carcinoma (HCC). Eighty-nine patients with advanced HCC underwent DCE-MRI before and within 1 week following systemic therapy. The relative changes of six DCE-MRI parameters (Peak, Slope, AUC, Ktrans, Kep and Ve) of the tumours were correlated with OS using the Kaplan-Meier model and the double-sided log-rank test. All patients died and the median survival was 174 days. Among the six DCE-MRI parameters, reductions in Peak, AUC, and Ktrans, were significantly correlated with one another. In addition, patients with a high Peak reduction following treatment had longer OS (P = 0.023) compared with those with a low Peak reduction. In multivariate analysis, a high Peak reduction was an independent favourable prognostic factor in all patients [hazard ratio (HR), 0.622; P = 0.038] after controlling for age, sex, treatment methods, tumour size and stage, and Eastern Cooperative Oncology Group performance status. Early perfusion changes within 1 week following systemic therapy measured by DCE-MRI may aid in the prediction of the clinical outcome in patients with advanced HCC. (orig.)

  14. The Comparison of Computed Tomography Perfusion, Contrast-Enhanced Computed Tomography and Positron-Emission Tomography/Computed Tomography for the Detection of Primary Esophageal Carcinoma.

    Science.gov (United States)

    Genc, Berhan; Kantarci, Mecit; Sade, Recep; Orsal, Ebru; Ogul, Hayri; Okur, Aylin; Aydin, Yener; Karaca, Leyla; Eroğlu, Atilla

    2016-01-01

    The purpose of this study was to investigate the efficiency of computed tomography perfusion (CTP), contrast-enhanced computed tomography (CECT) and 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron-emission tomography (PET/CT) in the diagnosis of esophageal cancer. This prospective study consisted of 33 patients with pathologically confirmed esophageal cancer, 2 of whom had an esophageal abscess. All the patients underwent CTP, CECT and PET/CT imaging and the imaging findings were evaluated. Sensitivity, specificity and positive and negative predictive values were calculated for each of the 3 imaging modalities relative to the histological diagnosis. Thirty-three tumors were visualized on CTP, 29 on CECT and 27 on PET/CT. Six tumors were stage 1, and 2 and 4 of these tumors were missed on CECT and PET/CT, respectively. Significant differences between CTP and CECT (p = 0.02), and between CTP and PET/CT (p = 0.04) were found for stage 1 tumors. Values for the sensitivity, specificity and positive and negative predictive values on CTP were 100, 100, 100 and 100%, respectively. Corresponding values on CECT were 93.94, 0, 93.94 and 0%, respectively, and those on PET/CT were 87.88, 0, 93.55 and 0%, respectively. Hence, the sensitivity, specificity and positive and negative predictive values of CTP were better than those of CECT and PET/CT. CTP had an advantage over CECT and PET/CT in detecting small lesions. CTP was valuable, especially in detecting stage 1 tumors. © 2016 S. Karger AG, Basel.

  15. Evaluation of femoral perfusion using dynamic contrast-enhanced MRI after simultaneous initiation of electrical stimulation and steroid treatment in an osteonecrosis model.

    Science.gov (United States)

    Yamamoto, Hiroki; Ueshima, Keiichiro; Saito, Masazumi; Ikoma, Kazuya; Ishida, Masashi; Goto, Tsuyoshi; Hayashi, Shigeki; Ikegami, Akira; Fujioka, Mikihiro; Mazda, Osam; Kubo, Toshikazu

    2018-04-30

    This study aimed to evaluate femoral perfusion using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for two weeks after the simultaneous initiation of electrical stimulation (ES) and steroid treatment in a steroid-induced osteonecrosis (ON) model. A single dose of methylprednisolone was injected into 14 rabbits. Seven rabbits underwent ES (ES group), and seven rabbits did not (control group). DCE-MRI was performed before steroid administration and 1, 5, 10, and 14 days after steroid administration. Regions of interest were set in the bilateral proximal femora. The enhancement ratio, initial slope, and area under the curve were analyzed. These parameters were evaluated after steroid administration in each group and between the two groups, and the ratios of ON in both groups were compared. In the control group, the minimum values of all parameters decreased significantly after steroid administration (P < 0.05), but in the ES group, the parameters did not decrease. In the ES group, all parameter values were significantly increased on the 10th and 14th days (P < 0.05). All parameter values in the ES group were significantly higher than those in the control group on the 14th day (P < 0.05). In the control group, ON was detected in three of five rabbits (in three of ten femora). In the ES group, ON was not detected. These results suggest that increased femoral blood flow elicited by ES may be related to ON prevention after steroid administration.

  16. Solitary pulmonary nodules: Comparison of dynamic first-pass contrast-enhanced perfusion area-detector CT, dynamic first-pass contrast-enhanced MR imaging, and FDG PET/CT.

    Science.gov (United States)

    Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Seki, Shinichiro; Tsubakimoto, Maho; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

    2015-02-01

    To prospectively compare the capabilities of dynamic perfusion area-detector computed tomography (CT), dynamic magnetic resonance (MR) imaging, and positron emission tomography (PET) combined with CT (PET/CT) with use of fluorine 18 fluorodeoxyglucose (FDG) for the diagnosis of solitary pulmonary nodules. The institutional review board approved this study, and written informed consent was obtained from each subject. A total of 198 consecutive patients with 218 nodules prospectively underwent dynamic perfusion area-detector CT, dynamic MR imaging, FDG PET/CT, and microbacterial and/or pathologic examinations. Nodules were classified into three groups: malignant nodules (n = 133) and benign nodules with low (n = 53) or high (n = 32) biologic activity. Total perfusion was determined with dual-input maximum slope models at area-detector CT, maximum and slope of enhancement ratio at MR imaging, and maximum standardized uptake value (SUVmax) at PET/CT. Next, all indexes for malignant and benign nodules were compared with the Tukey honest significant difference test. Then, receiver operating characteristic analysis was performed for each index. Finally, sensitivity, specificity, and accuracy were compared with the McNemar test. All indexes showed significant differences between malignant nodules and benign nodules with low biologic activity (P Dynamic perfusion area-detector CT is more specific and accurate than dynamic MR imaging and FDG PET/CT in the diagnosis of solitary pulmonary nodules in routine clinical practice. © RSNA, 2014.

  17. Pediatric hemiplegic migraine: susceptibility weighted and MR perfusion imaging abnormality

    International Nuclear Information System (INIS)

    Altinok, Deniz; Agarwal, Ajay; Ascadi, Gyula; Luat, Aimee; Tapos, Daniela

    2010-01-01

    We report on an 11-year-old girl suffering from a typical attack of hemiplegic migraine with characteristic abnormalities in perfusion MR and susceptibility-weighted MR imaging findings. The imaging abnormalities were resolved 48 h after the attack. Susceptibility-weighted MR imaging findings correlated well with the MR perfusion, thus it can be used along with conventional MRI for evaluation of children with complex migraine attacks. Susceptibility-weighted MR imaging might have a diagnostic role in assessing the vascular events in hemiplegic migraine. (orig.)

  18. Pediatric hemiplegic migraine: susceptibility weighted and MR perfusion imaging abnormality

    Energy Technology Data Exchange (ETDEWEB)

    Altinok, Deniz; Agarwal, Ajay [Children' s Hospital of Michigan, Department of Radiology, Detroit, MI (United States); Ascadi, Gyula; Luat, Aimee; Tapos, Daniela [Children' s Hospital of Michigan, Department of Neurology, Detroit, MI (United States)

    2010-12-15

    We report on an 11-year-old girl suffering from a typical attack of hemiplegic migraine with characteristic abnormalities in perfusion MR and susceptibility-weighted MR imaging findings. The imaging abnormalities were resolved 48 h after the attack. Susceptibility-weighted MR imaging findings correlated well with the MR perfusion, thus it can be used along with conventional MRI for evaluation of children with complex migraine attacks. Susceptibility-weighted MR imaging might have a diagnostic role in assessing the vascular events in hemiplegic migraine. (orig.)

  19. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Fujisawa, Yasuko [Toshiba Medical Systems Corporation, Otawara (Japan); Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Sugihara, Naoki [Toshiba Medical Systems Corporation, Otawara (Japan); Yoshikawa, Takeshi [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan)

    2017-01-15

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV{sub max}, and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r{sup 2} = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV{sub max}. Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  20. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    International Nuclear Information System (INIS)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2017-01-01

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV max , and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r 2 = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV max . Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  1. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT.

    Science.gov (United States)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2017-01-01

    To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR+PR) and 2) stable or progressive disease (SD+PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV max , and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. The step-wise regression test showed that therapeutic effect (r 2 =0.63, p=0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV max . Mean overall survival showed a significant difference for total perfusion (p=0.003) and systemic arterial perfusion (p=0.04). Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Brain capillary transit time heterogeneity in healthy volunteers measured by dynamic contrast-enhanced T1-weighted perfusion MRI

    DEFF Research Database (Denmark)

    Larsson, Henrik B.W.; Vestergaard, Mark B.; Lindberg, Ulrich

    2017-01-01

    Purpose: Capillary transit time heterogeneity, measured as CTH, may set the upper limit for extraction of substances in brain tissue, e.g., oxygen. The purpose of this study was to investigate the feasibility of dynamic contrast-enhanced T1 weighted MRI (DCE-MRI) at 3 Tesla (T), in estimating CTH...

  3. Comparison of first-pass and second-bolus dynamic susceptibility perfusion MRI in brain tumors

    International Nuclear Information System (INIS)

    Spampinato, M.V.; Besenski, Nada; Rumboldt, Zoran; Wooten, Caroline; Dorlon, Margaret

    2006-01-01

    Our goal was to evaluate whether the T1 shortening effect caused by contrast leakage into brain tumors, a well-known confounding effect in the quantification of relative cerebral blood volume (rCBV) measurements, may be corrected by the administration of a predose of gadolinium-DTPA. As part of their presurgical imaging protocol, 25 patients with primary brain tumors underwent two consecutive dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion MR studies. Intratumoral rCBV measurements and normalized rCBV values obtained during the first-pass and second-bolus studies were compared (Wilcoxon signed-ranks test). The frequency of relatively increased rCBV ratios on the second-bolus study was compared between enhancing and non-enhancing neoplasms (Fisher's exact test). Postprocessing perfusion studies were evaluated for image quality on a scale of 0-3 (Wilcoxon signed-ranks test). Four studies were excluded due to unacceptable image quality. Mean normalized rCBVs were 9.04 (SD 4.64) for the first-pass and 7.99 (SD 3.84) for the second-bolus study. There was no statistically significant difference between the two perfusion studies in either intratumoral rCBV (P=0.237) or rCBV ratio (P=0.181). Five enhancing and four non-enhancing tumors showed a relative increase in rCBV ratio on the second-bolus study, without a significant difference between the groups. Image quality was not significantly different between perfusion studies. Our results did not demonstrate a significant difference between first-pass and second-bolus rCBV measurements in DSC perfusion MR imaging. The administration of a predose of gadolinium-DTPA does not appear to be an efficient way of compensating for the underestimation of intratumoral rCBV values due to the T1 shortening effect. (orig.)

  4. Dynamic Contrast-Enhanced Magnetic Resonance Enterography and Dynamic Contrast-Enhanced Ultrasonography in Crohn's Disease

    DEFF Research Database (Denmark)

    Wilkens, Rune; Peters, David A; Nielsen, Agnete Hedemann

    2017-01-01

    Purpose e Cross-sectional imaging methods are important for objective evaluationof small intestinal inflammationinCrohn'sdisease(CD).The primary aim was to compare relative parameters of intestinal perfusion between contrast-enhanced ultrasonography (CEUS) and dynamic contrast-enhanced magnetic...

  5. Dynamic Contrast-Enhanced Perfusion Area-Detector CT: Preliminary Comparison of Diagnostic Performance for N Stage Assessment With FDG PET/CT in Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Sugihara, Naoki; Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Yoshikawa, Takeshi

    2017-11-01

    The objective of our study was to directly compare the capability of dynamic first-pass contrast-enhanced (CE) perfusion area-detector CT (ADCT) and FDG PET/CT for differentiation of metastatic from nonmetastatic lymph nodes and assessment of N stage in patients with non-small cell lung carcinoma (NSCLC). Seventy-seven consecutive patients, 45 men (mean age ± SD, 70.4 ± 5.9 years) and 32 women (71.2 ± 7.7 years), underwent dynamic first-pass CE-perfusion ADCT at two or three different positions for covering the entire thorax, FDG PET/CT, surgical treatment, and pathologic examination. From all ADCT data for each of the subjects, a whole-chest perfusion map was computationally generated using the dual- and single-input maximum slope and Patlak plot methods. For quantitative N stage assessment, perfusion parameters and the maximum standardized uptake value (SUV max ) for each lymph node were determined by measuring the relevant ROI. ROC curve analyses were performed for comparing the diagnostic capability of each of the methods on a per-node basis. N stages evaluated by each of the indexes were then statistically compared with the final pathologic diagnosis by means of chi-square and kappa statistics. The area under the ROC curve (A z ) values of systemic arterial perfusion (A z = 0.89), permeability surface (A z = 0.78), and SUV max (A z = 0.85) were significantly larger than the A z values of total perfusion (A z = 0.70, p Dynamic first-pass CE-perfusion ADCT is as useful as FDG PET/CT for the differentiation of metastatic from nonmetastatic lymph nodes and assessment of N stage in patients with NSCLC.

  6. Autoregressive moving average (ARMA) model applied to quantification of cerebral blood flow using dynamic susceptibility contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Murase, Kenya; Yamazaki, Youichi; Shinohara, Masaaki

    2003-01-01

    The purpose of this study was to investigate the feasibility of the autoregressive moving average (ARMA) model for quantification of cerebral blood flow (CBF) with dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI) in comparison with deconvolution analysis based on singular value decomposition (DA-SVD). Using computer simulations, we generated a time-dependent concentration of the contrast agent in the volume of interest (VOI) from the arterial input function (AIF) modeled as a gamma-variate function under various CBFs, cerebral blood volumes and signal-to-noise ratios (SNRs) for three different types of residue function (exponential, triangular, and box-shaped). We also considered the effects of delay and dispersion in AIF. The ARMA model and DA-SVD were used to estimate CBF values from the simulated concentration-time curves in the VOI and AIFs, and the estimated values were compared with the assumed values. We found that the CBF value estimated by the ARMA model was more sensitive to the SNR and the delay in AIF than that obtained by DA-SVD. Although the ARMA model considerably overestimated CBF at low SNRs, it estimated the CBF more accurately than did DA-SVD at high SNRs for the exponential or triangular residue function. We believe this study will contribute to an understanding of the usefulness and limitations of the ARMA model when applied to quantification of CBF with DSC-MRI. (author)

  7. Pulmonary Perfusion Changes as Assessed by Contrast-Enhanced Dual-Energy Computed Tomography after Endoscopic Lung Volume Reduction by Coils.

    Science.gov (United States)

    Lador, Frédéric; Hachulla, Anne-Lise; Hohn, Olivia; Plojoux, Jérôme; Ronot, Maxime; Montet, Xavier; Soccal, Paola M

    2016-01-01

    Endoscopic lung volume reduction by coils (LVRC) is a recent treatment approach for severe emphysema. Furthermore, dual-energy computed tomography (DECT) now offers a combined assessment of lung morphology and pulmonary perfusion. The aim of our study was to assess the impact of LVRC on pulmonary perfusion with DECT. Seventeen patients (64.8 ± 6.7 years) underwent LVRC. DECT was performed prior to and after LVRC. For each patient, lung volumes and emphysema quantification were automatically calculated. Then, 6 regions of interest (ROIs) on the iodine perfusion map were drawn in the anterior, mid, and posterior right and left lungs at 4 defined levels. The ROI values were averaged to obtain lung perfusion as assessed by the lung's iodine concentration (CLung, μg·cm-3). The CLung values were normalized using the left atrial iodine concentration (CLA) to take into account differences between successive DECT scans. The 6-min walk distance (6MWD) improved significantly after the procedure (p = 0.0002). No lung volume changes were observed between successive DECT scans for any of the patients (p = 0.32), attesting the same suspended inspiration. After LVRC, the emphysema index was significantly reduced in the treated lung (p = 0.0014). Lung perfusion increased significantly adjacent to the treated areas (CLung/CLA from 3.4 ± 1.7 to 5.6 ± 2.2, p < 0.001) and in the ipsilateral untreated areas (from 4.1 ± 1.4 to 6.6 ± 1.7, p < 0.001), corresponding to a mean 65 and 61% increase in perfusion, respectively. No significant difference was observed in the contralateral upper and lower areas (from 4.4 ± 1.9 to 4.8 ± 2.1, p = 0.273, and from 4.9 ± 2.0 to 5.2 ± 1.7, p = 0.412, respectively). A significant correlation between increased 6MWD and increased perfusion was found (p = 0.0027, R2 = 0.3850). Quantitative analysis based on DECT acquisition revealed that LVRC results in a significant increase in perfusion in the coil-free areas adjacent to the treated ones, as

  8. An Exploratory Study Into the Role of Dynamic Contrast-Enhanced Magnetic Resonance Imaging or Perfusion Computed Tomography for Detection of Intratumoral Hypoxia in Head-and-Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Newbold, Kate [Royal Marsden Hospital, Sutton (United Kingdom); Castellano, Isabel [Institute of Cancer Research, London (United Kingdom); Charles-Edwards, Elizabeth [Institute of Cancer Research, Sutton, Surrey (United Kingdom); Mears, Dorothy; Sohaib, Aslam [Royal Marsden Hospital, Sutton (United Kingdom); Leach, Martin [Institute of Cancer Research, Sutton, Surrey (United Kingdom); Rhys-Evans, Peter; Clarke, Peter; Fisher, Cyril [Royal Marsden Hospital, London (United Kingdom); Harrington, Kevin [Institute of Cancer Research, London (United Kingdom); Royal Marsden Hospital, London (United Kingdom); Nutting, Christopher [Royal Marsden Hospital, London (United Kingdom)

    2009-05-01

    Purpose: Hypoxia in patients with head-and-neck cancer (HNC) is well established and known to cause radiation resistance and treatment failure in the management of HNC. This study examines the role of parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and perfusion computed tomography (CT) as surrogate markers of intratumoral hypoxia, defined by using the exogenous marker of hypoxia pimonidazole and the endogenous marker carbonic anhydrase 9 (CA9). Methods and Materials: Patients with HNC underwent preoperative DCE-MRI, perfusion CT, and pimonidazole infusion. Imaging parameters were correlated with pimonidazole and CA9 staining. The strength of correlations was tested by using a two-tailed Spearman's rank correlation coefficient. Results: Twenty-three regions of interest were analyzed from the 7 patients who completed the DCE-MRI studies. A number of statistically significant correlations were seen between DCE-MRI parameters (volume transfer between blood plasma and extracellular extravascular space [EES], volume of EES, rate constant between EES and blood plasma, time at arrival of contrast inflow, time to peak, average gradient, and time to onset) and areas with a pimonidazole score of 4. In the case of CA9 staining, only a weak correlation was shown with wash-in rate. There were no significant correlations between perfusion CT parameters and pimonidazole staining or CA9 expression. Conclusion: Intratumoral hypoxia in patients with HNC may be predicted by using DCE-MRI; however, perfusion CT requires further investigation.

  9. Measurement of brain perfusion, blood volume, and blood-brain barrier permeability, using dynamic contrast-enhanced T(1)-weighted MRI at 3 tesla

    DEFF Research Database (Denmark)

    Larsson, Henrik B W; Courivaud, Frédéric; Rostrup, Egill

    2009-01-01

    Assessment of vascular properties is essential to diagnosis and follow-up and basic understanding of pathogenesis in brain tumors. In this study, a procedure is presented that allows concurrent estimation of cerebral perfusion, blood volume, and blood-brain permeability from dynamic T(1)-weighted...... on a pixel-by-pixel basis of cerebral perfusion, cerebral blood volume, and blood-brain barrier permeability.......Assessment of vascular properties is essential to diagnosis and follow-up and basic understanding of pathogenesis in brain tumors. In this study, a procedure is presented that allows concurrent estimation of cerebral perfusion, blood volume, and blood-brain permeability from dynamic T(1)-weighted...... imaging of a bolus of a paramagnetic contrast agent passing through the brain. The methods are applied in patients with brain tumors and in healthy subjects. Perfusion was estimated by model-free deconvolution using Tikhonov's method (gray matter/white matter/tumor: 72 +/- 16/30 +/- 8/56 +/- 45 mL/100 g...

  10. Myocardial perfusion quantification using simultaneously acquired 13 NH3 -ammonia PET and dynamic contrast-enhanced MRI in patients at rest and stress.

    Science.gov (United States)

    Kunze, Karl P; Nekolla, Stephan G; Rischpler, Christoph; Zhang, Shelley HuaLei; Hayes, Carmel; Langwieser, Nicolas; Ibrahim, Tareq; Laugwitz, Karl-Ludwig; Schwaiger, Markus

    2018-04-19

    Systematic differences with respect to myocardial perfusion quantification exist between DCE-MRI and PET. Using the potential of integrated PET/MRI, this study was conceived to compare perfusion quantification on the basis of simultaneously acquired 13 NH 3 -ammonia PET and DCE-MRI data in patients at rest and stress. Twenty-nine patients were examined on a 3T PET/MRI scanner. DCE-MRI was implemented in dual-sequence design and additional T 1 mapping for signal normalization. Four different deconvolution methods including a modified version of the Fermi technique were compared against 13 NH 3 -ammonia results. Cohort-average flow comparison yielded higher resting flows for DCE-MRI than for PET and, therefore, significantly lower DCE-MRI perfusion ratios under the common assumption of equal arterial and tissue hematocrit. Absolute flow values were strongly correlated in both slice-average (R 2  = 0.82) and regional (R 2  = 0.7) evaluations. Different DCE-MRI deconvolution methods yielded similar flow result with exception of an unconstrained Fermi method exhibiting outliers at high flows when compared with PET. Thresholds for Ischemia classification may not be directly tradable between PET and MRI flow values. Differences in perfusion ratios between PET and DCE-MRI may be lifted by using stress/rest-specific hematocrit conversion. Proper physiological constraints are advised in model-constrained deconvolution. © 2018 International Society for Magnetic Resonance in Medicine.

  11. Analysis of perfusion defects by causes other than acute pulmonary thromboembolism on contrast-enhanced dual-energy CT in consecutive 537 patients

    International Nuclear Information System (INIS)

    Kim, Bo Hyun; Seo, Joon Beom; Chae, Eun Jin; Lee, Hyun Joo; Hwang, Hye Jeon; Lim, Chaehun

    2012-01-01

    Objective: To assess causes, incidence and patterns of perfusion defects (PDs) on dual-energy perfusion CT angiography (DECTA) in clinically suspected acute pulmonary thromboembolisms (PTE). Materials and methods: Consecutive 537 patients who underwent DECTA for suspicion of PTE were retrospectively reviewed. After excluding patients with possible PTE or unsatisfactory perfusion map quality, 299 patients with 1697 lobes were included. The DECTA (Somatom Definition, Siemens) was performed at 140 kV and 80 kV. Color-coded perfusion images were obtained with a lung PBV application of the workstation software (Syngo Dual Energy). The presence, incidence, three patterns of PDs (wedge-shaped, heterogeneous, and regionally homogeneous), pulmonary diseases, and the matchedness between the PD and the disease extent were studied. Results: 315 of 1697 lobes (18.6%) in 156 of 299 patients (81.3%) showed PDs. Among them, 51 (3%), 257 (15.1%), and 7 (0.4%) lobes had PDs due to vascular, nonvascular, and unidentifiable causes, respectively. Vascular causes include: pulmonary arterial (PA) hypertension (0.7%), extrinsic occlusion of PA by fibrosis (0.6%), PA hypoplasia (0.6%), vasculitis (0.5%), cancer mass compressing PA, venous occlusion, AVM, and pulmonary angiosarcoma. Most of PDs were wedge-shaped and well-matched. Nonvascular causes include: mosaic attenuation (4.1%), emphysema (3.2%), interstitial fibrosis (1.6%), bronchitis (1.4%), GGO (1.2%), cellular bronchiolitis (1%), bronchiectasis, airway obstruction, compensaroty lung hyperinflation, air trapping, cor-pulmonale, bronchopneumonia, physiologic decreased ventilation, and segmental bronchial atresia. Most of PDs showed heterogeneous pattern and were not matched. Conclusions: Various vascular and nonvascular diseases cause PDs on DECTA. Each disease shows different pattern of PD depending on pathophysiology and physiologic compensation.

  12. Arterial spin labelling MRI for assessment of cerebral perfusion in children with moyamoya disease: comparison with dynamic susceptibility contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Goetti, Robert [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland); University Hospital Zurich, Department of Diagnostic and Interventional Radiology, Zurich (Switzerland); O' Gorman, Ruth [University Children' s Hospital Zurich, Center for MR Research, Zurich (Switzerland); Khan, Nadia [University Children' s Hospital Zurich, Moyamoya Center, Division of Neurosurgery, Department of Surgery, Zurich (Switzerland); Kellenberger, Christian J.; Scheer, Ianina [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland)

    2013-05-15

    This study seeks to evaluate the diagnostic accuracy of cerebral perfusion imaging with arterial spin labelling (ASL) MR imaging in children with moyamoya disease compared to dynamic susceptibility contrast (DSC) imaging. Ten children (7 females; age, 9.2 {+-} 5.4 years) with moyamoya disease underwent cerebral perfusion imaging with ASL and DSC on a 3-T MRI scanner in the same session. Cerebral perfusion images were acquired with ASL (pulsed continuous 3D ASL sequence, 32 axial slices, TR = 5.5 s, TE = 25 ms, FOV = 24 cm, matrix = 128 x 128) and DSC (gradient echo EPI sequence, 35 volumes of 28 axial slices, TR = 2,000 ms, TE = 36 ms, FOV = 24 cm, matrix = 96 x 96, 0.2 ml/kg Gd-DOTA). Cerebral blood flow maps were generated. ASL and DSC images were qualitatively assessed regarding perfusion of left and right ACA, MCA, and PCA territories by two independent readers using a 3-point-Likert scale and quantitative relative cerebral blood flow (rCBF) was calculated. Correlation between ASL and DSC for qualitative and quantitative assessment and the accuracy of ASL for the detection of reduced perfusion per territory with DSC serving as the standard of reference were calculated. With a good interreader agreement ({kappa} = 0.62) qualitative perfusion assessment with ASL and DSC showed a strong and significant correlation ({rho} = 0.77; p < 0.001), as did quantitative rCBF (r = 0.79; p < 0.001). ASL showed a sensitivity, specificity and accuracy of 94 %, 93 %, and 93 % for the detection of reduced perfusion per territory. In children with moyamoya disease, unenhanced ASL enables the detection of reduced perfusion per vascular territory with a good accuracy compared to contrast-enhanced DSC. (orig.)

  13. Voxelwise comparison of perfusion parameters estimated using dynamic contrast enhanced (DCE) computed tomography and DCE-magnetic resonance imaging in locally advanced cervical cancer

    International Nuclear Information System (INIS)

    Kallehauge; Jesper; Nielsen, Thomas; Haack, Soeren

    2013-01-01

    Purpose: Dynamic contrast enhanced (DCE) imaging has gained interest as an imaging modality for assessment of tumor characteristics and response to cancer treatment. However, for DCE-magnetic resonance imaging (MRI) tissue contrast enhancement may vary depending on imaging sequence and temporal resolution. The aim of this study is to compare DCE-MRI to DCE-computed tomography (DCE-CT) as the gold standard. Material and methods: Thirteen patients with advanced cervical cancer were scanned once prior to chemo-radiation and during chemo-radiation with DCE-CT and -MRI in immediate succession. A total of 22 paired DCE-CT and -MRI scans were acquired for comparison. Kinetic modeling using the extended Tofts model was applied to both image series. Furthermore the similarity of the spatial distribution was evaluated using a G analysis. The correlation between the two imaging techniques was evaluated using Pe arson's correlation and the parameter means were compared using a Student's t-test (p trans (r = 0.9), flux rate constant k ep (r = 0.77), extracellular volume fraction v e (r = 0.58) and blood plasma volume fraction v p (r = 0.83). All quantitative parameters were found to be significantly different as estimated by DCE-CT and -MRI. The G analysis in normalized maps revealed that 45 % of the voxels failed to find a voxel with the corresponding value allowing for an uncertainty of 3 mm in position and 3 % in value (G 3,3 ). By reducing the criteria, the G-failure rates were: G 3,5 (37 % failure), G 3,10 (26% failure) and at G 3,15 (19 % failure). Conclusion: Good to excellent correlations but significant bias was found between DCE-CT and -MRI. Both the Pearson's correlation and the G analysis proved that the spatial information was similar when analyzing the two sets of DCE data using the extended Tofts model. Improvement of input function sampling is needed to improve kinetic quantification using DCE-MRI

  14. Grading diffuse gliomas without intense contrast enhancement by amide proton transfer MR imaging: comparisons with diffusion- and perfusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Togao, Osamu; Hiwatashi, Akio; Yamashita, Koji; Kikuchi, Kazufumi; Honda, Hiroshi [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences, Fukuoka (Japan); Keupp, Jochen [Philips Research, Hamburg (Germany); Yoshimoto, Koji; Kuga, Daisuke; Iihara, Koji [Kyushu University, Department of Neurosurgery, Graduate School of Medical Sciences, Fukuoka (Japan); Yoneyama, Masami [Philips Electronics Japan, Tokyo (Japan); Suzuki, Satoshi O.; Iwaki, Toru [Kyushu University, Department of Neuropathology, Graduate School of Medical Sciences, Fukuoka (Japan); Takahashi, Masaya [Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX (United States)

    2017-02-15

    To investigate whether amide proton transfer (APT) MR imaging can differentiate high-grade gliomas (HGGs) from low-grade gliomas (LGGs) among gliomas without intense contrast enhancement (CE). This retrospective study evaluated 34 patients (22 males, 12 females; age 36.0 ± 11.3 years) including 20 with LGGs and 14 with HGGs, all scanned on a 3T MR scanner. Only tumours without intense CE were included. Two neuroradiologists independently performed histogram analyses to measure the 90th-percentile (APT{sub 90}) and mean (APT{sub mean}) of the tumours' APT signals. The apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) were also measured. The parameters were compared between the groups with Student's t-test. Diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis. The APT{sub 90} (2.80 ± 0.59 % in LGGs, 3.72 ± 0.89 in HGGs, P = 0.001) and APT{sub mean} (1.87 ± 0.49 % in LGGs, 2.70 ± 0.58 in HGGs, P = 0.0001) were significantly larger in the HGGs compared to the LGGs. The ADC and rCBV values were not significantly different between the groups. Both the APT{sub 90} and APT{sub mean} showed medium diagnostic performance in this discrimination. APT imaging is useful in discriminating HGGs from LGGs among diffuse gliomas without intense CE. (orig.)

  15. Detection of bridging veins draining into superior sagittal sinus by using susceptibility weighted imaging and three dimensional contrast enhancement MR venography

    International Nuclear Information System (INIS)

    Xia Chunhua; Chen Dan; Chen Bing; Wang Yajun; Xia Shiyong; Liu Wenli; Zhang Zhenhua; Wang Hui; Wu Lingqiao

    2011-01-01

    Objective: To use the superior sagittal sinus (SSS) as an example to identify anatomical features of the bridging veins (BVs) draining into the SSS in both susceptibility weighted imaging (SWI) and three dimensional contrast enhancement MR venography (3D-CEMRV) images. Methods: A total of 20 healthy volunteers (40 sides) were examined in this study. The venograms of each patient was obtained from SWI (40 sides out of 20 volunteers) and 3D-CE MRV (40 sides out of 20 volunteers). The data were analyzed by t test. Results: According to their draining location with respect to the SSS, bridging veins were divided into two groups. Between the anterior group and the posterior group were two segments of the SSS into which few bridging veins drained. Observed by 3D-CE MRV and SWI, the average numbers of the anterior group were 1.9±0.6 and 3.2±0.8, respectively, and the average diameters of the anterior group were (3.4±1.1) and (2.1±0.5) mm, respectively. These differences between 3D-CE MRV and SWI images were significant (t=11.23, 9.76, P<0.01). Observed by 3D-CE MRV and SWI, the average numbers of the posterior group were 3.5±1.2 and 5.9±1.1, respectively, and the average diameters of the posterior group were (3.7±0.9) and (2.9±0.7) mm, respectively. The differences between the two technique were significant as well (t=11.51, 8.47, P<0.01). Conclusion: The dural entrance of BVs into the SSS can be identified in both SWI and 3D-CE MRV images. The preoperative venogram by using 3D-CE MRV and SWI is useful to design a individual-tailored surgical approach for the preservation of BVs draining into SSS. SWI outweighs 3D-CE MRV in identifying anatomical features of the dural entrance of BVs into the SSS. (authors)

  16. Theoretical considerations in measurement of time discrepancies between input and myocardial time-signal intensity curves in estimates of regional myocardial perfusion with first-pass contrast-enhanced MRI.

    Science.gov (United States)

    Natsume, Takahiro; Ishida, Masaki; Kitagawa, Kakuya; Nagata, Motonori; Sakuma, Hajime; Ichihara, Takashi

    2015-11-01

    The purpose of this study was to develop a method to determine time discrepancies between input and myocardial time-signal intensity (TSI) curves for accurate estimation of myocardial perfusion with first-pass contrast-enhanced MRI. Estimation of myocardial perfusion with contrast-enhanced MRI using kinetic models requires faithful recording of contrast content in the blood and myocardium. Typically, the arterial input function (AIF) is obtained by setting a region of interest in the left ventricular cavity. However, there is a small delay between the AIF and the myocardial curves, and such time discrepancies can lead to errors in flow estimation using Patlak plot analysis. In this study, the time discrepancies between the arterial TSI curve and the myocardial tissue TSI curve were estimated based on the compartment model. In the early phase after the arrival of the contrast agent in the myocardium, the relationship between rate constant K1 and the concentrations of Gd-DTPA contrast agent in the myocardium and arterial blood (LV blood) can be described by the equation K1={dCmyo(tpeak)/dt}/Ca(tpeak), where Cmyo(t) and Ca(t) are the relative concentrations of Gd-DTPA contrast agent in the myocardium and in the LV blood, respectively, and tpeak is the time corresponding to the peak of Ca(t). In the ideal case, the time corresponding to the maximum upslope of Cmyo(t), tmax, is equal to tpeak. In practice, however, there is a small difference in the arrival times of the contrast agent into the LV and into the myocardium. This difference was estimated to correspond to the difference between tpeak and tmax. The magnitudes of such time discrepancies and the effectiveness of the correction for these time discrepancies were measured in 18 subjects who underwent myocardial perfusion MRI under rest and stress conditions. The effects of the time discrepancies could be corrected effectively in the myocardial perfusion estimates. Copyright © 2015 Elsevier Inc. All rights

  17. Quantitative contrast-enhanced first-pass cardiac perfusion MRI at 3 tesla with accurate arterial input function and myocardial wall enhancement.

    Science.gov (United States)

    Breton, Elodie; Kim, Daniel; Chung, Sohae; Axel, Leon

    2011-09-01

    To develop, and validate in vivo, a robust quantitative first-pass perfusion cardiovascular MR (CMR) method with accurate arterial input function (AIF) and myocardial wall enhancement. A saturation-recovery (SR) pulse sequence was modified to sequentially acquire multiple slices after a single nonselective saturation pulse at 3 Tesla. In each heartbeat, an AIF image is acquired in the aortic root with a short time delay (TD) (50 ms), followed by the acquisition of myocardial images with longer TD values (∼150-400 ms). Longitudinal relaxation rates (R(1) = 1/T(1)) were calculated using an ideal saturation recovery equation based on the Bloch equation, and corresponding gadolinium contrast concentrations were calculated assuming fast water exchange condition. The proposed method was validated against a reference multi-point SR method by comparing their respective R(1) measurements in the blood and left ventricular myocardium, before and at multiple time-points following contrast injections, in 7 volunteers. R(1) measurements with the proposed method and reference multi-point method were strongly correlated (r > 0.88, P < 10(-5)) and in good agreement (mean difference ±1.96 standard deviation 0.131 ± 0.317/0.018 ± 0.140 s(-1) for blood/myocardium, respectively). The proposed quantitative first-pass perfusion CMR method measured accurate R(1) values for quantification of AIF and myocardial wall contrast agent concentrations in 3 cardiac short-axis slices, in a total acquisition time of 523 ms per heartbeat. Copyright © 2011 Wiley-Liss, Inc.

  18. Evaluation of myocardial perfusion reserve in patients with CAD using Contrast-Enhanced MRI: A comparison between semiquantitative and quantitative methods

    International Nuclear Information System (INIS)

    Schmitt, M.; Mohrs, O.K.; Petersen, S.E.; Kreitner, K.F.

    2002-01-01

    Objective: Comparison between two semiquantitative methods and a quantitative evaluation of myocardial blood flow (MBF) for assessment of myocardial perfusion reserve (MPR) in patients with CAD. Material and Methods: 9 patients with coronary stenoses>50% were examined with an ECG-gated Saturation Recovery Turbo FLASH sequence by using Gd-DTPA as contrast agent (CA). The entive measurements were performed both during rest and hyperemia induced by adenosine. The up-slopes of the signal-time S(t) curves in the myocardium and left ventricular (LV) cavity were evaluated by a linear fit. MPR was calculated from the original up-slopes of the myocardial S(t) curves and from the up-slopes, which were normalized to the up-slopes of the LV S(t) curves, respectively. For quantification of MBF values, the mathematical model MMID 4 was used and MPR was evaluated from the MBF values. Results: With all tested methods, MPR was reduced in myocardial regions subtended by arteries with stenoses≥70% compared with remote regions. With MMID 4 and the normalized up-slope method, differences between severe ischemic and remote regions were statistically significant. Conclusion: The up-slope method with normalization and quantification with MMID 4 are more sensitive methods to differentiate between remote and ischemic myocardium than the up-slope method without normalization. (orig.) [de

  19. Is there any correlation between model-based perfusion parameters and model-free parameters of time-signal intensity curve on dynamic contrast enhanced MRI in breast cancer patients?

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Boram; Kang, Doo Kyoung; Kim, Tae Hee [Ajou University School of Medicine, Department of Radiology, Suwon, Gyeonggi-do (Korea, Republic of); Yoon, Dukyong [Ajou University School of Medicine, Department of Biomedical Informatics, Suwon (Korea, Republic of); Jung, Yong Sik; Kim, Ku Sang [Ajou University School of Medicine, Department of Surgery, Suwon (Korea, Republic of); Yim, Hyunee [Ajou University School of Medicine, Department of Pathology, Suwon (Korea, Republic of)

    2014-05-15

    To find out any correlation between dynamic contrast-enhanced (DCE) model-based parameters and model-free parameters, and evaluate correlations between perfusion parameters with histologic prognostic factors. Model-based parameters (Ktrans, Kep and Ve) of 102 invasive ductal carcinomas were obtained using DCE-MRI and post-processing software. Correlations between model-based and model-free parameters and between perfusion parameters and histologic prognostic factors were analysed. Mean Kep was significantly higher in cancers showing initial rapid enhancement (P = 0.002) and a delayed washout pattern (P = 0.001). Ve was significantly lower in cancers showing a delayed washout pattern (P = 0.015). Kep significantly correlated with time to peak enhancement (TTP) (ρ = -0.33, P < 0.001) and washout slope (ρ = 0.39, P = 0.002). Ve was significantly correlated with TTP (ρ = 0.33, P = 0.002). Mean Kep was higher in tumours with high nuclear grade (P = 0.017). Mean Ve was lower in tumours with high histologic grade (P = 0.005) and in tumours with negative oestrogen receptor status (P = 0.047). TTP was shorter in tumours with negative oestrogen receptor status (P = 0.037). We could acquire general information about the tumour vascular physiology, interstitial space volume and pathologic prognostic factors by analyzing time-signal intensity curve without a complicated acquisition process for the model-based parameters. (orig.)

  20. Dynamic contrast enhanced MRI in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Alonzi, Roberto [Marie Curie Research Wing, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, Middlesex, HA6 2RN (United Kingdom)], E-mail: robertoalonzi@btinternet.com; Padhani, Anwar R. [Paul Strickland Scanner Centre, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, Middlesex, HA6 2RN (United Kingdom); Synarc Inc. 575 Market Street, San Francisco, CA 94105 (United States)], E-mail: anwar.padhani@paulstrickland-scannercentre.org.uk; Allen, Clare [Department of Imaging, University College Hospital, London, 235 Euston Road, NW1 2BU (United Kingdom)], E-mail: clare.allen@uclh.nhs.uk

    2007-09-15

    Angiogenesis is an integral part of benign prostatic hyperplasia (BPH), is associated with prostatic intraepithelial neoplasia (PIN) and is key to the growth and for metastasis of prostate cancer. Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) using small molecular weight gadolinium chelates enables non-invasive imaging characterization of tissue vascularity. Depending on the technique used, data reflecting tissue perfusion, microvessel permeability surface area product, and extracellular leakage space can be obtained. Two dynamic MRI techniques (T{sub 2}*-weighted or susceptibility based and T{sub 1}-weighted or relaxivity enhanced methods) for prostate gland evaluations are discussed in this review with reference to biological basis of observations, data acquisition and analysis methods, technical limitations and validation. Established clinical roles of T{sub 1}-weighted imaging evaluations will be discussed including lesion detection and localisation, for tumour staging and for the detection of suspected tumour recurrence. Limitations include inadequate lesion characterisation particularly differentiating prostatitis from cancer, and in distinguishing between BPH and central gland tumours.

  1. Perfusion MRI of brain tumours: a comparative study of pseudo-continuous arterial spin labelling and dynamic susceptibility contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jaernum, Hanna; Steffensen, Elena G.; Simonsen, Carsten Wiberg; Jensen, Finn Taagehoej [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Knutsson, Linda [Lund University, Department of Medical Radiation Physics, Lund (Sweden); Fruend, Ernst-Torben [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); GE Healthcare - Applied Science Lab Europe, Aalborg (Denmark); Lundbye-Christensen, Soeren [Aalborg Hospital/Aarhus University Hospital, Department of Cardiology, Center for Cardiovascular Research, Aalborg (Denmark); Shankaranarayanan, Ajit [Global Applied Science Lab, GE Healthcare, Menlo Park, CA (United States); Alsop, David C. [Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA (United States); Larsson, Elna-Marie [Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Uppsala University Hospital, Department of Radiology, Uppsala (Sweden)

    2010-04-15

    The purpose of this study was to compare the non-invasive 3D pseudo-continuous arterial spin labelling (PC ASL) technique with the clinically established dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI) for evaluation of brain tumours. A prospective study of 28 patients with contrast-enhancing brain tumours was performed at 3 T using DSC-MRI and PC ASL with whole-brain coverage. The visual qualitative evaluation of signal enhancement in tumour was scored from 0 to 3 (0 = no signal enhancement compared with white matter, 3 = pronounced signal enhancement with equal or higher signal intensity than in grey matter/basal ganglia). The extent of susceptibility artefacts in the tumour was scored from 0 to 2 (0 = no susceptibility artefacts and 2 = extensive susceptibility artefacts (maximum diameter > 2 cm)). A quantitative analysis was performed with normalised tumour blood flow values (ASL nTBF, DSC nTBF): mean value for region of interest (ROI) in an area with maximum signal enhancement/the mean value for ROIs in cerebellum. There was no difference in total visual score for signal enhancement between PC ASL and DSC relative cerebral blood flow (p = 0.12). ASL had a lower susceptibility-artefact score than DSC-MRI (p = 0.03). There was good correlation between DSC nTBF and ASL nTBF values with a correlation coefficient of 0.82. PC ASL is an alternative to DSC-MRI for the evaluation of perfusion in brain tumours. The method has fewer susceptibility artefacts than DSC-MRI and can be used in patients with renal failure because no contrast injection is needed. (orig.)

  2. Assessment of cerebral perfusion with dynamic susceptibility contrast

    International Nuclear Information System (INIS)

    Takahashi, Kiyohiko; Naito, Isao; Nozokido, Takeshi; Sato, Takaaki; Takatama, Shin; Kimura, Tokunori

    2004-01-01

    Accurate measurements of arterial input function (AIF) are indispensable for the quantification of perfusion parameters such as mean transit time (MTT), cerebral blood volume (CBV), and cerebral blood flow (CBF). Quantification trials of cerebral perfusion using the disconsolation method with dynamic susceptibility contrast MRI (DSC-MRI) have been reported on. Accurately measuring AIF with DSC-MRI is difficult due to non-linearity and the limited dynamic range between ΔR 2 * and the concentration of contrast media. In this study, we assessed simple methods while using various parameters calculated by the tissue time intensity curve without measuring AIF. The parameters used were appearance time of contrast media (AT), 1'st moment (MT1), the full width at half maximum (FWHM), and up slope at maximum gradient (US). Difference of the appearance time (delta AT) and the CBFratio between the regions in question and the contralateral regions obtained by MT1, FWHM and US were assessed in 38 stroke patients. The CBF calculated by the linear scaling method using the signal of the ASL (ASL, CBF) was used as the standard for a correlation study. The delta AT in patients with middle cerebral artery occlusions supplied by retrograde flow indicated a significantly greater value as compared to patients with other lesions with antegrade flow. US CBF indicated the best correlation among the three CBFs obtained by MT1, FWHM and US. Both the ASL CBFratio and the US CBFratio correlated with delta AT, with the ASL CBFratio being predominant. The CBVratio-CBFratio map showed that the CBVratio tended to decrease when the CBFratio decreased. The map is useful in clinical analysis of cerebral perfusion due to its simplicity and ability to alleviate AIF dependent errors. The validity of the proposed method still needs to be examined by comparing it to the deconvolution method with DSC-MRI, since DSC-MRI can correct the effect of AIF. It might also be compared to Xenon CT, which is less

  3. Contrast-enhanced harmonic endoscopic ultrasound

    DEFF Research Database (Denmark)

    Săftoiu, A; Dietrich, C F; Vilmann, P

    2012-01-01

    Second-generation intravenous blood-pool ultrasound contrast agents are increasingly used in endoscopic ultrasound (EUS) for characterization of microvascularization, differential diagnosis of benign and malignant focal lesions, and improving staging and guidance of therapeutic procedures. Although...... initially used as Doppler signal enhancers, second-generation microbubble contrast agents are now used with specific contrast harmonic imaging techniques, which benefit from the highly nonlinear behavior of the microbubbles. Contrast-specific modes based on multi-pulse technology are used to perform...... contrast-enhanced harmonic EUS based on a very low mechanical index (0.08 - 0.12). Quantification techniques based on dynamic contrast-enhanced ultrasound have been recommended for perfusion imaging and monitoring of anti-angiogenic treatment, mainly based on time-intensity curve analysis. Most...

  4. Dynamic contrast enhanced ultrasound for therapy monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, John M. [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Williams, Ross [Imaging Research, Sunnybrook Research Institute, Toronto, ON (Canada); Tremblay-Darveau, Charles; Sheeran, Paul S. [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Milot, Laurent [Department of Medical Imaging, University of Toronto, Toronto, ON (Canada); Bjarnason, Georg A. [Department of Medical Oncology, University of Toronto, and Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); Burns, Peter N., E-mail: burns@sri.utoronto.ca [Department of Medical Biophysics, University of Toronto, Toronto, ON (Canada); Imaging Research, Sunnybrook Research Institute, Toronto, ON (Canada); Department of Medical Imaging, University of Toronto, Toronto, ON (Canada)

    2015-09-15

    Quantitative imaging is a crucial component of the assessment of therapies that target the vasculature of angiogenic or inflamed tissue. Dynamic contrast-enhanced ultrasound (DCE-US) using microbubble contrast offers the advantages of being sensitive to perfusion, non-invasive, cost effective and well suited to repeated use at the bedside. Uniquely, it employs an agent that is truly intravascular. This papers reviews the principles and methodology of DCE-US, especially as applied to anti-angiogenic cancer therapies. Reproducibility is an important attribute of such a monitoring method: results are discussed. More recent technical advances in parametric and 3D DCE-US imaging are also summarised and illustrated.

  5. Contrast enhancement CT by iopamidol

    International Nuclear Information System (INIS)

    Mori, Masaki; Makita, Nobue; Yanai, Kyoko

    1984-01-01

    In order to evaluate the contrast enhancement effect and safety of iopamidol (IOP) in CT examination, IOP was compared with angiographin (AG). In the liver and abdominal aorta, peak CT values were obtained earlier and were higher in the group with AG than in the group with IOP. However, CT values in the group with IOP decreased a little more slowly than those in the group with AG. There was no significant difference in the effect on contrast enhancement between the groups. Intravenous injection of IOP caused lower degree of burning sensation than that of AG, and some of the patients with IOP did not feel burning sensation at all. Changes in clinical laboratory values were slight before and after intravenous injection of IOP. These results suggest that IOP is satisfactory in terms of safety and effect on contrast enhancement in CT examination. (Namekawa, K.)

  6. Application of histogram analysis for the evaluation of vascular permeability in glioma by the K2 parameter obtained with the dynamic susceptibility contrast method: Comparisons with Ktrans obtained with the dynamic contrast enhance method and cerebral blood volume.

    Science.gov (United States)

    Taoka, Toshiaki; Kawai, Hisashi; Nakane, Toshiki; Hori, Saeka; Ochi, Tomoko; Miyasaka, Toshiteru; Sakamoto, Masahiko; Kichikawa, Kimihiko; Naganawa, Shinji

    2016-09-01

    The "K2" value is a factor that represents the vascular permeability of tumors and can be calculated from datasets obtained with the dynamic susceptibility contrast (DSC) method. The purpose of the current study was to correlate K2 with Ktrans, which is a well-established permeability parameter obtained with the dynamic contrast enhance (DCE) method, and determine the usefulness of K2 for glioma grading with histogram analysis. The subjects were 22 glioma patients (Grade II: 5, III: 6, IV: 11) who underwent DSC studies, including eight patients in which both DSC and DCE studies were performed on separate days within 10days. We performed histogram analysis of regions of interest of the tumors and acquired 20th percentile values for leakage-corrected cerebral blood volume (rCBV20%ile), K2 (K220%ile), and for patients who underwent a DCE study, Ktrans (Ktrans20%ile). We evaluated the correlation between K220%ile and Ktrans20%ile and the statistical difference between rCBV20%ile and K220%ile. We found a statistically significant correlation between K220%ile and Ktrans20%ile (r=0.717, pK220%ile showed a statistically significant (pK2 value calculated from the DSC dataset, which can be obtained with a short acquisition time, showed a correlation with Ktrans obtained with the DCE method and may be useful for glioma grading when analyzed with histogram analysis. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncica, Ana Maria; Saftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...

  8. Perfusion imaging with magnetic-susceptibility contrast media

    International Nuclear Information System (INIS)

    Rosen, B.R.; Belliveau, J.W.; Betteridge, D.; Cohen, M.S.; Weisskoff, R.M.; Vevea, J.M.; Rzedzian, R.P.; Brady, T.J.

    1989-01-01

    In animal models, transient signal los on T2-weighted images has been well documented following intravenous injection of high-magnetic-susceptibility contrast agents that are compartmentalized within the brain intravascular space. These signal changes have been correlated with physiologic parameters, such as blood flow and volume. The advent of whole-body single-shot imaging capability, coupled with the approval of paramagnetic contrasts agents for human use, has enabled the authors to demonstrate susceptibility contrast in the human brain, allowing for generation of functional images. With use of a 1.5-T imaging system gradient-echo images (TE = 60 msec) were acquired in 75 msec. Sequential single-sections images were sampled every 1 second following bolus administration of 0.1 mmol/kg of Gd-DTPA

  9. Heterogeneity of pulmonary perfusion as a mechanistic image-based phenotype in emphysema susceptible smokers.

    Science.gov (United States)

    Alford, Sara K; van Beek, Edwin J R; McLennan, Geoffrey; Hoffman, Eric A

    2010-04-20

    Recent evidence suggests that endothelial dysfunction and pathology of pulmonary vascular responses may serve as a precursor to smoking-associated emphysema. Although it is known that emphysematous destruction leads to vasculature changes, less is known about early regional vascular dysfunction which may contribute to and precede emphysematous changes. We sought to test the hypothesis, via multidetector row CT (MDCT) perfusion imaging, that smokers showing early signs of emphysema susceptibility have a greater heterogeneity in regional perfusion parameters than emphysema-free smokers and persons who had never smoked (NS). Assuming that all smokers have a consistent inflammatory response, increased perfusion heterogeneity in emphysema-susceptible smokers would be consistent with the notion that these subjects may have the inability to block hypoxic vasoconstriction in patchy, small regions of inflammation. Dynamic ECG-gated MDCT perfusion scans with a central bolus injection of contrast were acquired in 17 NS, 12 smokers with normal CT imaging studies (SNI), and 12 smokers with subtle CT findings of centrilobular emphysema (SCE). All subjects had normal spirometry. Quantitative image analysis determined regional perfusion parameters, pulmonary blood flow (PBF), and mean transit time (MTT). Mean and coefficient of variation were calculated, and statistical differences were assessed with one-way ANOVA. MDCT-based MTT and PBF measurements demonstrate globally increased heterogeneity in SCE subjects compared with NS and SNI subjects but demonstrate similarity between NS and SNI subjects. These findings demonstrate a functional lung-imaging measure that provides a more mechanistically oriented phenotype that differentiates smokers with and without evidence of emphysema susceptibility.

  10. Quantitative contrast-enhanced optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Winetraub, Yonatan; SoRelle, Elliott D. [Molecular Imaging Program at Stanford, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Bio-X Program, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Biophysics Program, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Department of Structural Biology, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Liba, Orly [Molecular Imaging Program at Stanford, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Bio-X Program, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Department of Structural Biology, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Department of Electrical Engineering, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Zerda, Adam de la [Molecular Imaging Program at Stanford, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Bio-X Program, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Biophysics Program, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Department of Structural Biology, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States); Department of Electrical Engineering, Stanford University, 299 Campus Drive, Stanford, California 94305 (United States)

    2016-01-11

    We have developed a model to accurately quantify the signals produced by exogenous scattering agents used for contrast-enhanced Optical Coherence Tomography (OCT). This model predicts distinct concentration-dependent signal trends that arise from the underlying physics of OCT detection. Accordingly, we show that real scattering particles can be described as simplified ideal scatterers with modified scattering intensity and concentration. The relation between OCT signal and particle concentration is approximately linear at concentrations lower than 0.8 particle per imaging voxel. However, at higher concentrations, interference effects cause signal to increase with a square root dependence on the number of particles within a voxel. Finally, high particle concentrations cause enough light attenuation to saturate the detected signal. Predictions were validated by comparison with measured OCT signals from gold nanorods (GNRs) prepared in water at concentrations ranging over five orders of magnitude (50 fM to 5 nM). In addition, we validated that our model accurately predicts the signal responses of GNRs in highly heterogeneous scattering environments including whole blood and living animals. By enabling particle quantification, this work provides a valuable tool for current and future contrast-enhanced in vivo OCT studies. More generally, the model described herein may inform the interpretation of detected signals in modalities that rely on coherence-based detection or are susceptible to interference effects.

  11. Contrast enhanced ultrasound in the assessment of urogenital pathology

    Directory of Open Access Journals (Sweden)

    Libero Barozzi

    2014-12-01

    Full Text Available Contrast enhanced ultrasound (CEUS is an innovative technique that employs microbubble contrast agents to demonstrate parenchymal perfusion. Although initial clinical application was focused on the liver pathology, a wide variety of clinical conditions can be assessed now with CEUS. CEUS is a well-tolerated technique and is acquiring an increasing role in the assessment of renal pathology because contrast agents are not excreted by the kidney and do not affect the renal function. CEUS demonstrated an accuracy similar to contrast enhanced multi-detector computed tomography (CEMDCT in detecting focal lesions, with the advantage of the real-time assessment of microvascular perfusion by using time-intensity curves. The aim of this paper is to review the main indications of CEUS in the assessment of renal and urogenital pathology. Imaging examples are presented and described. Advantages and limitations of CEUS with reference to conventional US and CE-MDCT are discussed.

  12. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncică, Ana Maria; Săftoiu, Adrian

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest, to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures. We review the mechanisms of action of first, second and third generation contrast...... agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...... cancers and visualization of the portal venous system and esophageal varices. In addition, contrast agents can be used to differentiate pancreatic lesions. The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies. The sensitivity of power Doppler...

  13. Value of dynamic susceptibility contrast perfusion MRI in the acute phase of transient global amnesia.

    Directory of Open Access Journals (Sweden)

    Alex Förster

    Full Text Available Transient global amnesia (TGA is a transitory, short-lasting neurological disorder characterized by a sudden onset of antero- and retrograde amnesia. Perfusion abnormalities in TGA have been evaluated mainly by use of positron emission tomography (PET or single-photon emission computed tomography (SPECT. In the present study we explore the value of dynamic susceptibility contrast perfusion-weighted MRI (PWI in TGA in the acute phase.From a MRI report database we identified TGA patients who underwent MRI including PWI in the acute phase and compared these to control subjects. Quantitative perfusion maps (cerebral blood flow (CBF and volume (CBV were generated and analyzed by use of Signal Processing In NMR-Software (SPIN. CBF and CBV values in subcortical brain regions were assessed by use of VOI created in FIRST, a model-based segmentation tool in the Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB Software Library (FSL.Five TGA patients were included (2 men, 3 women. On PWI, no relevant perfusion alterations were found by visual inspection in TGA patients. Group comparisons for possible differences between TGA patients and control subjects showed significant lower rCBF values bilaterally in the hippocampus, in the left thalamus and globus pallidus as well as bilaterally in the putamen and the left caudate nucleus. Correspondingly, significant lower rCBV values were observed bilaterally in the hippocampus and the putamen as well as in the left caudate nucleus. Group comparisons for possible side differences in rCBF and rCBV values in TGA patients revealed a significant lower rCBV value in the left caudate nucleus.Mere visual inspection of PWI is not sufficient for the assessment of perfusion changes in TGA in the acute phase. Group comparisons with healthy control subjects might be useful to detect subtle perfusion changes on PWI in TGA patients. However, this should be confirmed in larger data sets and serial PWI

  14. Contrast enhanced CT of spinal cord angioma

    International Nuclear Information System (INIS)

    Nakamura, Takahiko; Ebitani, Tsutomu; Honma, Takao; Sofue, Muroto; Nakamura, Shigeru

    1982-01-01

    Contrast enhanced CT on 6 patients with spinal cord angioma showed enhancement in 2 of them. The conditions to produce contrast enhancement were the window width of 100 - 200, and the window level of 0 - 50. In spinal cord angioma, contrast enhanced CT is presently only an adjunct to angiography and myelography. Nevertheless, contrast enhanced CT is useful in the screening test for spinal cord angioma, in the patients who are nonindicated to angiography, and in the postoperative follow-up. (Ueda, J.)

  15. Perfusion- and pattern-based quantitative CT indexes using contrast-enhanced dual-energy computed tomography in diffuse interstitial lung disease: relationships with physiologic impairment and prediction of prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jung Won [Sungkyunkwan University School of Medicine, Department of Radiology, Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Bae, Jang Pyo; Kim, Namkug; Chang, Yongjun; Seo, Joon Beom [University of Ulsan College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Lee, Ho Yun; Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Chung, Man Pyo; Park, Hye Yun [Sungkyunkwan University School of Medicine, Department of Pulmonology, Samsung Medical Center, Seoul (Korea, Republic of)

    2016-05-15

    To evaluate automated texture-based segmentation of dual-energy CT (DECT) images in diffuse interstitial lung disease (DILD) patients and prognostic stratification by overlapping morphologic and perfusion information of total lung. Suspected DILD patients scheduled for surgical biopsy were prospectively included. Texture patterns included ground-glass opacity (GGO), reticulation and consolidation. Pattern- and perfusion-based CT measurements were assessed to extract quantitative parameters. Accuracy of texture-based segmentation was analysed. Correlations between CT measurements and pulmonary function test or 6-minute walk test (6MWT) were calculated. Parameters of idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP) and non-IPF/UIP were compared. Survival analysis was performed. Overall accuracy was 90.47 % for whole lung segmentation. Correlations between mean iodine values of total lung, 50-97.5th (%) attenuation and forced vital capacity or 6MWT were significant. Volume of GGO, reticulation and consolidation had significant correlation with DLco or SpO{sub 2} on 6MWT. Significant differences were noted between IPF/UIP and non-IPF/UIP in 6MWT distance, mean iodine value of total lung, 25-75th (%) attenuation and entropy. IPF/UIP diagnosis, GGO ratio, DILD extent, 25-75th (%) attenuation and SpO{sub 2} on 6MWT showed significant correlations with survival. DECT combined with pattern analysis is useful for analysing DILD and predicting survival by provision of morphology and enhancement. (orig.)

  16. Tumor Metabolism and Perfusion in Head and Neck Squamous Cell Carcinoma: Pretreatment Multimodality Imaging With 1H Magnetic Resonance Spectroscopy, Dynamic Contrast-Enhanced MRI, and [18F]FDG-PET

    International Nuclear Information System (INIS)

    Jansen, Jacobus F.A.; Schöder, Heiko; Lee, Nancy Y.; Stambuk, Hilda E.; Wang Ya; Fury, Matthew G.; Patel, Senehal G.; Pfister, David G.; Shah, Jatin P.; Koutcher, Jason A.; Shukla-Dave, Amita

    2012-01-01

    Purpose: To correlate proton magnetic resonance spectroscopy ( 1 H-MRS), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and 18 F-labeled fluorodeoxyglucose positron emission tomography ([ 18 F]FDG PET) of nodal metastases in patients with head and neck squamous cell carcinoma (HNSCC) for assessment of tumor biology. Additionally, pretreatment multimodality imaging was evaluated for its efficacy in predicting short-term response to treatment. Methods and Materials: Metastatic neck nodes were imaged with 1 H-MRS, DCE-MRI, and [ 18 F]FDG PET in 16 patients with newly diagnosed HNSCC, before treatment. Short-term patient radiological response was evaluated at 3 to 4 months. Correlations among 1 H-MRS (choline concentration relative to water [Cho/W]), DCE-MRI (volume transfer constant [K trans ]; volume fraction of the extravascular extracellular space [v e ]; and redistribution rate constant [k ep ]), and [ 18 F]FDG PET (standard uptake value [SUV] and total lesion glycolysis [TLG]) were calculated using nonparametric Spearman rank correlation. To predict short-term responses, logistic regression analysis was performed. Results: A significant positive correlation was found between Cho/W and TLG (ρ = 0.599; p = 0.031). Cho/W correlated negatively with heterogeneity measures of standard deviation std(v e ) (ρ = −0.691; p = 0.004) and std(k ep ) (ρ = −0.704; p = 0.003). Maximum SUV (SUVmax) values correlated strongly with MRI tumor volume (ρ = 0.643; p = 0.007). Logistic regression indicated that std(K trans ) and SUVmean were significant predictors of short-term response (p 1 H-MRS, DCE-MRI, and [ 18 F]FDG PET is feasible in HNSCC patients with nodal metastases. Additionally, combined DCE-MRI and [ 18 F]FDG PET parameters were predictive of short-term response to treatment.

  17. Quantitative imaging by pixel-based contrast-enhanced ultrasound reveals a linear relationship between synovial vascular perfusion and the recruitment of pathogenic IL-17A-F+IL-23+ CD161+ CD4+ T helper cells in psoriatic arthritis joints.

    Science.gov (United States)

    Fiocco, Ugo; Stramare, Roberto; Martini, Veronica; Coran, Alessandro; Caso, Francesco; Costa, Luisa; Felicetti, Mara; Rizzo, Gaia; Tonietto, Matteo; Scanu, Anna; Oliviero, Francesca; Raffeiner, Bernd; Vezzù, Maristella; Lunardi, Francesca; Scarpa, Raffaele; Sacerdoti, David; Rubaltelli, Leopoldo; Punzi, Leonardo; Doria, Andrea; Grisan, Enrico

    2017-02-01

    To develop quantitative imaging biomarkers of synovial tissue perfusion by pixel-based contrast-enhanced ultrasound (CEUS), we studied the relationship between CEUS synovial vascular perfusion and the frequencies of pathogenic T helper (Th)-17 cells in psoriatic arthritis (PsA) joints. Eight consecutive patients with PsA were enrolled in this study. Gray scale CEUS evaluation was performed on the same joint immediately after joint aspiration, by automatic assessment perfusion data, using a new quantification approach of pixel-based analysis and the gamma-variate model. The set of perfusional parameters considered by the time intensity curve includes the maximum value (peak) of the signal intensity curve, the blood volume index or area under the curve, (BVI, AUC) and the contrast mean transit time (MTT). The direct ex vivo analysis of the frequencies of SF IL17A-F + CD161 + IL23 + CD4 + T cells subsets were quantified by fluorescence-activated cell sorter (FACS). In cross-sectional analyses, when tested for multiple comparison setting, a false discovery rate at 10%, a common pattern of correlations between CEUS Peak, AUC (BVI) and MTT parameters with the IL17A-F + IL23 + - IL17A-F + CD161 + - and IL17A-F + CD161 + IL23 + CD4 + T cells subsets, as well as lack of correlation between both peak and AUC values and both CD4 + T and CD4 + IL23 + T cells, was observed. The pixel-based CEUS assessment is a truly measure synovial inflammation, as a useful tool to develop quantitative imaging biomarker for monitoring target therapeutics in PsA.

  18. Contrast-enhanced ultrasonography depicts small tumor vessels for the evaluation of pancreatic tumors

    International Nuclear Information System (INIS)

    Okamoto, Yuko; Kawamoto, Hirofumi; Takaki, Akinobu; Ishida, Etsuji; Ogawa, Tsuneyoshi; Kuwaki, Kenji; Kobayashi, Yoshiyuki; Sakaguchi, Kohsaku; Shiratori, Yasushi

    2007-01-01

    Objective: The aim of this study is to evaluate the efficacy of contrast-enhanced ultrasonography for the diagnosis of pancreatic tumors. Materials and methods: Contrast-enhanced ultrasonography with Levovist was performed on 62 consecutive patients (53 with pancreatic cancer, 4 with islet cell tumor, 3 with inflammatory pancreatic tumor, and 2 with metastatic tumor). The vascular and perfusion image phases of the tumors were evaluated and compared with the findings of contrast-enhanced computed tomography. Results: Contrast-enhanced ultrasonography showed tumor vessels around and/or in the tumor at the vascular image phase in 79% of pancreatic cancer patients (42/53). At the perfusion image phase, 96% of pancreatic cancers (51/53) were classified as hypo-enhancement type. However, tiny spotty or irregular heterogeneous enhanced lesions were found in 84% of hypo-enhanced pancreatic cancer patients (43/51). The presence of small vessels at the vascular image phase was closely correlated with the presence of these intratumor regional enhanced lesions at the perfusion image phase (κ coefficient = 0.42). The sensitivity of contrast-enhanced ultrasonography (100%) for pancreatic cancer was superior to that of contrast-enhanced computed tomography (91%), but no significant difference was observed between the two (McNemar test: p = 0.063). Conclusion: Contrast-enhanced ultrasonography with Levovist successfully visualizes fine vessels and enhancement in pancreatic tumors, and is useful for evaluating pancreatic tumors

  19. Characterisation of focal liver lesions with contrast enhanced ultrasonography

    International Nuclear Information System (INIS)

    Dietrich, Christoph F.

    2004-01-01

    Ultrasound contrast agents (USCA) have improved the detection rate of liver tumours in recent years. Conventional ultrasound has been reported to be relatively unreliable in the characterisation of liver tumours. SonoVue [reg] (Bracco Imaging Spa) has been shown to be particularly advantageous in the differentiation of benign and malignant liver tumours and, therefore, possibly represents a new cost-effective competitive alternative to other liver imaging modalities (e.g. computed tomography and magnetic resonance imaging), thus allowing these important technologies to be available for other indications (e.g. brain, thorax). More detailed and specific liver tumour characterisation is possible in about 80% of liver tumours due to typical vascularity and perfusion patterns. The role of USCA for better characterisation, which is possible through the analysis of flow characteristics in real time, places a particular emphasis on agent use. Contrast enhanced real-time imaging techniques with SonoVue [reg] allow real-time analysis of tumour perfusion in patients with liver lesions. Liver tumours known to be hyperperfused in the arterial phase (e.g. focal nodular hyperplasia, hepatocellular adenoma and carcinoma, and hyperperfused metastases) can be better detected and characterised. Hypoperfused tumours (e.g. liver metastases of the gastrointestinal tract) can be recognised in the portal venous phase as less perfused 'black spots'. In this article we discuss liver tumour characterisation by contrast enhanced ultrasonography

  20. Contrast-enhanced MRI of the lung

    International Nuclear Information System (INIS)

    Kauczor, Hans-Ulrich; Kreitner, Karl-Friedrich

    2000-01-01

    The lung has long been neglected by MR imaging. This is due to unique intrinsic difficulties: (1) signal loss due to cardiac pulsation and respiration; (2) susceptibility artifacts caused by multiple air-tissue interfaces; (3) low proton density. There are many MR strategies to overcome these problems. They consist of breath-hold imaging, respiratory and cardiac gating procedures, use of short repetition and echo times, increase of the relaxivity of existing spins by administration of intravenous contrast agents, and enrichment of spin density by hyperpolarized noble gases or oxygen. Improvements in scanner performance and frequent use of contrast media have increased the interest in MR imaging and MR angiography of the lung. They can be used on a routine basis for the following indications: characterization of pulmonary nodules, staging of bronchogenic carcinoma, in particular assessment of chest wall invasion; evaluation of inflammatory activity in interstitial lung disease; acute pulmonary embolism, chronic thromboembolic pulmonary hypertension, vascular involvement in malignant disease; vascular abnormalities. Future perspectives include perfusion imaging using extracellular or intravascular (blood pool) contrast agents and ventilation imaging using inhalation of hyperpolarized noble gases, of paramagnetic oxygen or of aerosolized contrast agents. These techniques represent new approaches to functional lung imaging. The combination of visualization of morphology and functional assessment of ventilation and perfusion is unequalled by any other technique

  1. Paradoxical perfusion metrics of high-grade gliomas with an oligodendroglioma component: quantitative analysis of dynamic susceptibility contrast perfusion MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sunwoo, Leonard; Park, Sun-Won [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul Metropolitan Government - Seoul National University Boramae Medical Center, Department of Radiology, Seoul (Korea, Republic of); Choi, Seung Hong [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University, Center for Nanoparticle Research, Institute for Basic Science, and School of Chemical and Biological Engineering, Seoul (Korea, Republic of); Yoo, Roh-Eul; Kang, Koung Mi; Yun, Tae Jin; Kim, Ji-hoon; Sohn, Chul-Ho [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Kim, Tae Min; Lee, Se-Hoon [Seoul National University Hospital, Department of Internal Medicine, Seoul (Korea, Republic of); Park, Chul-Kee [Seoul National University Hospital, Department of Neurosurgery, Seoul (Korea, Republic of); Won, Jae-Kyung; Park, Sung-Hye [Seoul National University Hospital, Department of Pathology, Seoul (Korea, Republic of); Kim, Il Han [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of)

    2015-11-15

    The aim of this study is to investigate perfusion characteristics of glioblastoma with an oligodendroglioma component (GBMO) compared with conventional glioblastoma (GBM) using dynamic susceptibility contrast (DSC) perfusion magnetic resonance (MR) imaging and microvessel density (MVD). The study was approved by the institutional review board. Newly diagnosed high-grade glioma patients were enrolled (n = 72; 20 GBMs, 14 GBMOs, 19 anaplastic astrocytomas (AAs), 13 anaplastic oligodendrogliomas (AOs), and six anaplastic oligoastrocytomas (AOAs)). All participants underwent preoperative MR imaging including DSC perfusion MR imaging. Normalized cerebral blood volume (nCBV) values were analyzed using a histogram approach. Histogram parameters were subsequently compared across each tumor subtype and grade. MVD was quantified by immunohistochemistry staining and correlated with perfusion parameters. Progression-free survival (PFS) was assessed according to the tumor subtype. GBMO displayed significantly reduced nCBV values compared with GBM, whereas grade III tumors with oligodendroglial components (AO and AOA) exhibited significantly increased nCBV values compared with AA (p < 0.001). MVD analyses revealed the same pattern as nCBV results. In addition, a positive correlation between MVD and nCBV values was noted (r = 0.633, p < 0.001). Patients with oligodendroglial tumors exhibited significantly increased PFS compared with patients with pure astrocytomas in each grade. In contrast to grade III tumors, the presence of oligodendroglial components in grade IV tumors resulted in paradoxically reduced perfusion metrics and MVD. In addition, patients with GBMO exhibited a better clinical outcome compared with patients with GBM. (orig.)

  2. The Future of Contrast-Enhanced Mammography.

    Science.gov (United States)

    Covington, Matthew F; Pizzitola, Victor J; Lorans, Roxanne; Pockaj, Barbara A; Northfelt, Donald W; Appleton, Catherine M; Patel, Bhavika K

    2018-02-01

    The purpose of this article is to discuss facilitators of and barriers to future implementation of contrast-enhanced mammography (CEM) in the United States. CEM provides low-energy 2D mammographic images analogous to digital mammography and contrast-enhanced recombined images that allow assessment of neovascularity similar to that offered by MRI. The utilization of CEM in the United States is currently low but could increase rapidly given the many potential indications for its clinical use.

  3. Contrast Enhanced US in the Abdomen

    International Nuclear Information System (INIS)

    Chung, Yong Eun; Kim, Ki Whang

    2012-01-01

    Contrast enhanced ultrasound, which was introduced in 1996, has been widely used in Europe and Eastern Asia. Ultrasound contrast agent can be classified as first generation and second generation, depending on the gas within the microbubble. With the first generation contrast agent, the high MI technique was used, and only intermittent scanning was possible due to destruction of the microbubble during scanning. Use of the second generation contrast agent with the low MI technique makes continuous scanning possible. Contrast enhanced US can be used in detection and differentiation of focal liver lesions. It is also helpful for monitoring of radiofrequency ablation and for targeting of US guided biopsy. Currently, because morphologic criteria alone may not reflect the response of the tumor to treatment, new criteria are needed for treatment evaluation after administration of anti-angiogenic agents. Contrast enhanced US could provide quantitative markers for evaluation of the response to treatment via use of dynamic contrast enhanced US. Due to cost-effectiveness, contrast enhanced US is not yet widely used in Korea; however, considering recent issues regarding contrast agent related adverse reaction, such as contrast induced nephropathy and nephrogenic systemic fibrosis, and radiation exposure, contrast enhanced US might be more widely used in Korea, as an alternative imaging modality in the future.

  4. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...... in cerebral hemodynamics than noncontrast-enhanced imaging. The results of the deconvolution analysis suggested that perfusion calculation by conventional tracer kinetic methods may be impracticable because of nonlinear effects in contrast-enhanced MR imaging....

  5. Toward fully automated processing of dynamic susceptibility contrast perfusion MRI for acute ischemic cerebral stroke.

    Science.gov (United States)

    Kim, Jinsuh; Leira, Enrique C; Callison, Richard C; Ludwig, Bryan; Moritani, Toshio; Magnotta, Vincent A; Madsen, Mark T

    2010-05-01

    We developed fully automated software for dynamic susceptibility contrast (DSC) MR perfusion-weighted imaging (PWI) to efficiently and reliably derive critical hemodynamic information for acute stroke treatment decisions. Brain MR PWI was performed in 80 consecutive patients with acute nonlacunar ischemic stroke within 24h after onset of symptom from January 2008 to August 2009. These studies were automatically processed to generate hemodynamic parameters that included cerebral blood flow and cerebral blood volume, and the mean transit time (MTT). To develop reliable software for PWI analysis, we used computationally robust algorithms including the piecewise continuous regression method to determine bolus arrival time (BAT), log-linear curve fitting, arrival time independent deconvolution method and sophisticated motion correction methods. An optimal arterial input function (AIF) search algorithm using a new artery-likelihood metric was also developed. Anatomical locations of the automatically determined AIF were reviewed and validated. The automatically computed BAT values were statistically compared with estimated BAT by a single observer. In addition, gamma-variate curve-fitting errors of AIF and inter-subject variability of AIFs were analyzed. Lastly, two observes independently assessed the quality and area of hypoperfusion mismatched with restricted diffusion area from motion corrected MTT maps and compared that with time-to-peak (TTP) maps using the standard approach. The AIF was identified within an arterial branch and enhanced areas of perfusion deficit were visualized in all evaluated cases. Total processing time was 10.9+/-2.5s (mean+/-s.d.) without motion correction and 267+/-80s (mean+/-s.d.) with motion correction on a standard personal computer. The MTT map produced with our software adequately estimated brain areas with perfusion deficit and was significantly less affected by random noise of the PWI when compared with the TTP map. Results of image

  6. Post-traumatic contrast enhancing brain lesion

    International Nuclear Information System (INIS)

    Kim, Dae Jung; Kim, Hyun Sook; Jeong, Min Sun; Kim, Deok Ryeong; Cho, Young Kwon; Choi, Yun Sun

    2014-01-01

    Only a few studies have been reported on the MR contrast enhancement and the apparent diffusion coefficient (ADC) findings of the post-traumatic lesion of the brain. We report a case of the venous ischemia in the left frontal lobe observed in the MRI obtained one day after the incidence of trauma. Considering the presented slight increase in the ADC, the vasogenic edema was thought to be the major mechanism of the venous ischemia and excitotoxic injury. In spite of a slight increase in the ADC, the hyperintensity in the diffusion weighted imaging and contrast-enhanced areas eventually changed into hemorrhagic lesions.

  7. Post-traumatic contrast enhancing brain lesion

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Jung; Kim, Hyun Sook; Jeong, Min Sun; Kim, Deok Ryeong; Cho, Young Kwon; Choi, Yun Sun [Eulji Hospital, Eulji University College of Medicine, Seoul (Korea, Republic of)

    2014-10-15

    Only a few studies have been reported on the MR contrast enhancement and the apparent diffusion coefficient (ADC) findings of the post-traumatic lesion of the brain. We report a case of the venous ischemia in the left frontal lobe observed in the MRI obtained one day after the incidence of trauma. Considering the presented slight increase in the ADC, the vasogenic edema was thought to be the major mechanism of the venous ischemia and excitotoxic injury. In spite of a slight increase in the ADC, the hyperintensity in the diffusion weighted imaging and contrast-enhanced areas eventually changed into hemorrhagic lesions.

  8. Is correction necessary when clinically determining quantitative cerebral perfusion parameters from multi-slice dynamic susceptibility contrast MR studies?

    International Nuclear Information System (INIS)

    Salluzzi, M; Frayne, R; Smith, M R

    2006-01-01

    Several groups have modified the standard singular value decomposition (SVD) algorithm to produce delay-insensitive cerebral blood flow (CBF) estimates from dynamic susceptibility contrast (DSC) perfusion studies. However, new dependences of CBF estimates on bolus arrival times and slice position in multi-slice studies have been recently recognized. These conflicting findings can be reconciled by accounting for several experimental and algorithmic factors. Using simulation and clinical studies, the non-simultaneous measurement of arterial and tissue concentration curves (relative slice position) in a multi-slice study is shown to affect time-related perfusion parameters, e.g. arterial-tissue-delay measurements. However, the current clinical impact of relative slice position on amplitude-related perfusion parameters, e.g. CBF, can be expected to be small unless any of the following conditions are present individually or in combination: (a) high concentration curve signal-to-noise ratios, (b) small tissue mean transit times, (c) narrow arterial input functions or (d) low temporal resolution of the DSC image sequence. Recent improvements in magnetic resonance (MR) technology can easily be expected to lead to scenarios where these effects become increasingly important sources of inaccuracy for all perfusion parameter estimates. We show that using Fourier interpolated (high temporal resolution) residue functions reduces the systematic error of the perfusion parameters obtained from multi-slice studies

  9. International guidelines for contrast-enhanced ultrasonography

    DEFF Research Database (Denmark)

    Nolsøe, Christian Pállson; Lorentzen, Torben

    2016-01-01

    The intent of this review is to discuss and comment on common clinical scenarios in which contrast-enhanced ultrasonography (CEUS) may play a decisive role and to illustrate important points with typical cases. With the advent of CEUS, the scope of indications for ultrasonography has been dramati...

  10. Medial tibial pain: a dynamic contrast-enhanced MRI study.

    Science.gov (United States)

    Mattila, K T; Komu, M E; Dahlström, S; Koskinen, S K; Heikkilä, J

    1999-09-01

    The purpose of this study was to compare the sensitivity of different magnetic resonance imaging (MRI) sequences to depict periosteal edema in patients with medial tibial pain. Additionally, we evaluated the ability of dynamic contrast-enhanced imaging (DCES) to depict possible temporal alterations in muscular perfusion within compartments of the leg. Fifteen patients with medial tibial pain were examined with MRI. T1-, T2-weighted, proton density axial images and dynamic and static phase post-contrast images were compared in ability to depict periosteal edema. STIR was used in seven cases to depict bone marrow edema. Images were analyzed to detect signs of compartment edema. Region-of-interest measurements in compartments were performed during DCES and compared with controls. In detecting periosteal edema, post-contrast T1-weighted images were better than spin echo T2-weighted and proton density images or STIR images, but STIR depicted the bone marrow edema best. DCES best demonstrated the gradually enhancing periostitis. Four subjects with severe periosteal edema had visually detectable pathologic enhancement during DCES in the deep posterior compartment of the leg. Percentage enhancement in the deep posterior compartment of the leg was greater in patients than in controls. The fast enhancement phase in the deep posterior compartment began slightly slower in patients than in controls, but it continued longer. We believe that periosteal edema in bone stress reaction can cause impairment of venous flow in the deep posterior compartment. MRI can depict both these conditions. In patients with medial tibial pain, MR imaging protocol should include axial STIR images (to depict bone pathology) with T1-weighted axial pre and post-contrast images, and dynamic contrast enhanced imaging to show periosteal edema and abnormal contrast enhancement within a compartment.

  11. Clinical evaluation of contrast-enhanced digital mammography and contrast enhanced tomosynthesis--Comparison to contrast-enhanced breast MRI.

    Science.gov (United States)

    Chou, Chen-Pin; Lewin, John M; Chiang, Chia-Ling; Hung, Bao-Hui; Yang, Tsung-Lung; Huang, Jer-Shyung; Liao, Jia-Bin; Pan, Huay-Ben

    2015-12-01

    To compare the diagnostic accuracy of contrast-enhanced digital mammography (CEDM) and contrast-enhanced tomosynthesis (CET) to dynamic contrast enhanced breast MRI (DCE-MRI) using a multireader-multicase study. Institutional review board approval and informed consents were obtained. Total 185 patients (mean age 51.3) with BI-RADS 4 or 5 lesions were evaluated before biopsy with mammography, tomosynthesis, CEDM, CET and DCE-MRI. Mediolateral-oblique and cranio-caudal views of the target breast CEDM and CET were acquired at 2 and 4 min after contrast agent injection. A mediolateral-oblique view of the non-target breast was taken at 6 min. Each lesion was scored with forced BI-RADS categories by three readers. Each reader interpreted lesions in the following order: mammography, tomosynthesis, CEDM, CET, and DCE-MRI during a single reading session. Histology showed 81 cancers and 144 benign lesions in the study. Of the 81 malignant lesions, 44% (36/81) were invasive and 56% (45/81) were non-invasive. Areas under the ROC curve, averaged for the 3 readers, were as follows: 0.897 for DCE-MRI, 0.892 for CET, 0.878 for CEDM, 0.784 for tomosynthesis and 0.740 for mammography. Significant differences in AUC were found between the group of contrast enhanced modalities (CEDM, CET, DCE-MRI) and the unenhanced modalities (all p0.05). CET and CEDM may be considered as an alternative modality to MRI for following up women with abnormal mammography. All three contrast modalities were superior in accuracy to conventional digital mammography with or without tomosynthesis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Contrast-Enhanced Ultrasonography in Crohn's Disease Diagnostics.

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Liebert, Ariel; Kłopocka, Maria; Serafin, Zbigniew

    2015-06-01

    The chronic nature of Crohn's disease (CD) implicates necessity of multiple control assessments throughout patient's life. It is accepted that in patients with CD requiring disease monitoring, magnetic resonance enterography (MRE) and computed tomography enterography (CTE) are--apart from endoscopy--imaging studies of first choice. In practice, diagnostic imaging of patients with CD is troublesome, since MRE is an expensive and complicated study, and CTE exposes patients to high doses of ionizing radiation. Therefore, there is a need for new, both non-invasive and effective, methods of imaging in CD. Contrast-Enhanced Ultrasonography (CEUS) is a relatively new method using gas-filled microbubbles serving as contrast agent. It allows for detailed assessment of blood perfusion within intestine wall and peri-intestinal tissues, which enables detection and monitoring of inflammation and its qualitative assessment. The purpose of this paper is to describe CEUS examination technique and its clinical applications in patients with Crohn's disease.

  13. EFFECT OF SEDATION ON CONTRAST-ENHANCED ULTRASONOGRAPHY OF THE SPLEEN IN HEALTHY DOGS.

    Science.gov (United States)

    Rossi, Federica; Fina, Caroline; Stock, Emmelie; Vanderperren, Katrien; Duchateau, Luc; Saunders, Jimmy H

    2016-05-01

    Contrast-enhanced ultrasound of the spleen enables the dynamic assessment of the perfusion of this organ, however, both subjective and quantitative evaluation can be strongly influenced by sedative agent administration. The purpose of this prospective, experimental study was to test effects of two sedative agents on splenic perfusion during contrast-enhanced ultrasound of the spleen in a sample of healthy dogs. Contrast-enhanced ultrasound of the spleen was repeated in six healthy Beagles following a cross-over study design comparing three protocols: awake, butorphanol 0.2 mg/Kg intramuscular (IM), and dexmedetomidine 500 μg/m(2) IM. After intravenous injection of a phospholipid stabilized sulfur hexafluoride microbubble solution (SonoVue®, Bracco Imaging, Milano, Italy), the enhancement intensity and perfusion pattern of the splenic parenchyma were assessed and perfusion parameters were calculated. Normal spleen was slightly heterogeneous in the early phase, but the parenchyma was homogeneous at a later phase. Sedation with butorphanol did not modify perfusion of the spleen. Dexmedetomidine significantly reduced splenic enhancement, providing diffuse parenchymal hypoechogenicity during the entire examination. Measured parameters were significantly modified, with increased arrival time (AT; (dogs. Short-term and diffuse heterogeneity of the spleen in the early venous phase was determined to be a normal finding. © 2016 American College of Veterinary Radiology.

  14. Dynamic susceptibility contrast (DSC) perfusion MRI in differential diagnosis between radionecrosis and neoangiogenesis in cerebral metastases using rCBV, rCBF and K2.

    Science.gov (United States)

    Muto, Mario; Frauenfelder, Giulia; Senese, Rossana; Zeccolini, Fabio; Schena, Emiliano; Giurazza, Francesco; Jäger, Hans Rolf

    2018-07-01

    Distinction between treatment-related changes and tumour recurrence in patients who have received radiation treatment for brain metastases can be difficult on conventional MRI. In this study, we investigated the ability of dynamic susceptibility contrast (DSC) perfusion in differentiating necrotic changes from pathological angiogenesis and compared measurements of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and K2, using a dedicated software. Twenty-nine patients with secondary brain tumors were included in this retrospective study and underwent DSC perfusion MRI with a 3-month follow-up imaging after chemo- or radiation-therapy. Region-of-interests were drawn around the contrast enhancing lesions and measurements of rCBV, rCBF and K2 were performed in all patients. Based on subsequent histological examination or clinico-radiological follow-up, the cohort was divided in two groups: recurrent disease and stable disease. Differences between the two groups were analyzed using the Student's t test. Sensitivity, specificity and diagnostic accuracy of rCBV measurements were analyzed considering three different cut-off values. Between patients with and without disease, only rCBV and rCBF values were significant (p < 0.05). The only cut-off value giving the best diagnostic accuracy of 100% was rCBV = 2.1 (sensitivity = 100%; specificity = 100%). Patients with tumor recurrence showed a higher mean value of rCBV (mean = 4.28, standard deviation = 2.09) than patients with necrotic-related changes (mean = 0.77, standard deviation = 0.44). DSC-MRI appears a clinically useful method to differentiate between tumor recurrence, tumor necrosis and pseudoprogression in patients treated for cerebral metastases. Relative CBV using a cut-off value of 2.1 proved to be the most accurate and reliable parameter.

  15. The 'humble' bubble: Contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Marshall, Gill; Sykes, Anne; Berry, Jonathan; Jonker, Leon

    2011-01-01

    The use of contrast-enhanced ultrasound (CEUS) is increasing within the field of medical imaging. Ultrasonic contrast agent (UCA) contain gas microbubbles similar in size to red corpuscles which provide highly reflective interfaces, enabling dynamic demonstration of echogenic streams of the contrast within the anatomical area of interest on real-time grey scale ultrasound. Longevity of the microbubbles has been improved by changing their composition. The application of CEUS in the UK continues to grow, bringing it into territories historically occupied by computerised tomography (CT) scanning and magnetic resonance imaging (MRI). Hence, the role of CEUS may be of interest to all diagnostic imaging practitioners. Here we summarise the mode of action and use of CEUS, and its role within a range of applications. The potential risks of CEUS are compared to other contrast-enhanced imaging techniques. The benefits of CEUS and its implications for diagnostic imaging practice are also covered.

  16. Dual-energy contrast-enhanced mammography.

    Science.gov (United States)

    Travieso Aja, M M; Rodríguez Rodríguez, M; Alayón Hernández, S; Vega Benítez, V; Luzardo, O P

    2014-01-01

    The degree of vascularization in breast lesions is related to their malignancy. For this reason, functional diagnostic imaging techniques have become important in recent years. Dual-energy contrast-enhanced mammography is a new, apparently promising technique in breast cancer that provides information about the degree of vascularization of the lesion in addition to the morphological information provided by conventional mammography. This article describes the state of the art for dual-energy contrast-enhanced mammography. Based on 15 months' clinical experience, we illustrate this review with clinical cases that allow us to discuss the advantages and limitations of this technique. Copyright © 2014 SERAM. Published by Elsevier Espana. All rights reserved.

  17. Contrast Enhanced Spectral Mammography: A Review.

    Science.gov (United States)

    Patel, Bhavika K; Lobbes, M B I; Lewin, John

    2018-02-01

    Contrast-enhanced spectral mammography (CESM) provides low-energy 2D mammographic images comparable to standard digital mammography and a post-contrast recombined image to assess tumor neovascularity similar to magnetic resonance imaging (MRI). The utilization of CESM in the United States is currently low but could increase rapidly given many potential indications for clinical use. This article discusses historical background and literature review of indications and diagnostic accuracy of CESM to date. CESM is a growing technique for breast cancer detection and diagnosis that has levels of sensitivity and specificity on par with contrast-enhanced breast MRI. Because of its similar performance and ease of implementation, CESM is being adopted for multiple indications previously reserved for MRI, such as problem-solving, disease extent in newly diagnosed patients, and evaluating the treatment response of neoadjuvant chemotherapy. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Contrast-Enhanced Ultrasound in Vascular Surgery

    DEFF Research Database (Denmark)

    Bredahl, Kim; Mestre, Xavier Marti; Coll, Ramon Vila

    2017-01-01

    modalities. Ultrasound has only challenged these methods in assessment of carotid disease, aortic aneurysms, venous insufficiency, and thromboembolism and in surveillance of in situ bypasses. These practice patterns may change with the introduction of second-generation ultrasound contrast agents which...... are easy to use, manageable, and safe. This topical review attempts to summarize and highlight the current evidence and future prospects for contrast-enhanced ultrasound in vascular surgery, with a particular focus on opportunities in carotid and lower limb arteriosclerotic disease and surveillance after...

  19. Osteoblastic Metastases Mimickers on Contrast Enhanced CT

    Directory of Open Access Journals (Sweden)

    Fahad Al-Lhedan

    2017-01-01

    Full Text Available Secondary osseous involvement in lymphoma is more common compared to primary bone lymphoma. The finding of osseous lesion can be incidentally discovered during the course of the disease. However, osseous metastases are infrequently silent. Detection of osseous metastases is crucial for accurate staging and optimal treatment planning of lymphoma. The aim of imaging is to identify the presence and extent of osseous disease and to assess for possible complications such as pathological fracture of the load-bearing bones and cord compression if the lesion is spinal. We are presenting two patients with treated lymphoma who were in complete remission. On routine follow-up contrast enhanced CT, there were new osteoblastic lesions in the spine worrisome for metastases. Additional studies were performed for further evaluation of both of them which did not demonstrate any corresponding suspicious osseous lesion. The patients have a prior history of chronic venous occlusive thrombosis that resulted in collaterals formation. Contrast enhancement of the vertebral body marrow secondary to collaterals formation and venous flow through the vertebral venous plexus can mimic the appearance of spinal osteoblastic metastases.

  20. Morphological rational operator for contrast enhancement.

    Science.gov (United States)

    Peregrina-Barreto, Hayde; Herrera-Navarro, Ana M; Morales-Hernández, Luis A; Terol-Villalobos, Iván R

    2011-03-01

    Contrast enhancement is an important task in image processing that is commonly used as a preprocessing step to improve the images for other tasks such as segmentation. However, some methods for contrast improvement that work well in low-contrast regions affect good contrast regions as well. This occurs due to the fact that some elements may vanish. A method focused on images with different luminance conditions is introduced in the present work. The proposed method is based on morphological transformations by reconstruction and rational operations, which, altogether, allow a more accurate contrast enhancement resulting in regions that are in harmony with their environment. Furthermore, due to the properties of these morphological transformations, the creation of new elements on the image is avoided. The processing is carried out on luminance values in the u'v'Y color space, which avoids the creation of new colors. As a result of the previous considerations, the proposed method keeps the natural color appearance of the image.

  1. Adaptive multiscale processing for contrast enhancement

    Science.gov (United States)

    Laine, Andrew F.; Song, Shuwu; Fan, Jian; Huda, Walter; Honeyman, Janice C.; Steinbach, Barbara G.

    1993-07-01

    This paper introduces a novel approach for accomplishing mammographic feature analysis through overcomplete multiresolution representations. We show that efficient representations may be identified from digital mammograms within a continuum of scale space and used to enhance features of importance to mammography. Choosing analyzing functions that are well localized in both space and frequency, results in a powerful methodology for image analysis. We describe methods of contrast enhancement based on two overcomplete (redundant) multiscale representations: (1) Dyadic wavelet transform (2) (phi) -transform. Mammograms are reconstructed from transform coefficients modified at one or more levels by non-linear, logarithmic and constant scale-space weight functions. Multiscale edges identified within distinct levels of transform space provide a local support for enhancement throughout each decomposition. We demonstrate that features extracted from wavelet spaces can provide an adaptive mechanism for accomplishing local contrast enhancement. We suggest that multiscale detection and local enhancement of singularities may be effectively employed for the visualization of breast pathology without excessive noise amplification.

  2. Contrast enhancement of mail piece images

    Science.gov (United States)

    Shin, Yong-Chul; Sridhar, Ramalingam; Demjanenko, Victor; Palumbo, Paul W.; Hull, Jonathan J.

    1992-08-01

    A New approach to contrast enhancement of mail piece images is presented. The contrast enhancement is used as a preprocessing step in the real-time address block location (RT-ABL) system. The RT-ABL system processes a stream of mail piece images and locates destination address blocks. Most of the mail pieces (classified into letters) show high contrast between background and foreground. As an extreme case, however, the seasonal greeting cards usually use colored envelopes which results in reduced contrast osured by an error rate by using a linear distributed associative memory (DAM). The DAM is trained to recognize the spectra of three classes of images: with high, medium, and low OCR error rates. The DAM is not forced to make a classification every time. It is allowed to reject as unknown a spectrum presented that does not closely resemble any that has been stored in the DAM. The DAM was fairly accurate with noisy images but conservative (i.e., rejected several text images as unknowns) when there was little ground and foreground degradations without affecting the nondegraded images. This approach provides local enhancement which adapts to local features. In order to simplify the computation of A and (sigma) , dynamic programming technique is used. Implementation details, performance, and the results on test images are presented in this paper.

  3. MRI contrast enhancement using Magnetic Carbon Nanoparticles

    Science.gov (United States)

    Chaudhary, Rakesh P.; Kangasniemi, Kim; Takahashi, Masaya; Mohanty, Samarendra K.; Koymen, Ali R.; Department of Physics, University of Texas at Arlington Team; University of Texas Southwestern Medical Center Team

    2014-03-01

    In recent years, nanotechnology has become one of the most exciting forefront fields in cancer diagnosis and therapeutics such as drug delivery, thermal therapy and detection of cancer. Here, we report development of core (Fe)-shell (carbon) nanoparticles with enhanced magnetic properties for contrast enhancement in MRI imaging. These new classes of magnetic carbon nanoparticles (MCNPs) are synthesized using a bottom-up approach in various organic solvents, using the electric plasma discharge generated in the cavitation field of an ultrasonic horn. Gradient echo MRI images of well-dispersed MCNP-solutions (in tube) were acquired. For T2 measurements, a multi echo spin echo sequence was performed. From the slope of the 1/T2 versus concentration plot, the R2 value for different CMCNP-samples was measured. Since MCNPs were found to be extremely non-reactive, and highly absorbing in NIR regime, development of carbon-based MRI contrast enhancement will allow its simultaneous use in biomedical applications. We aim to localize the MCNPs in targeted tissue regions by external DC magnetic field, followed by MRI imaging and subsequent photothermal therapy.

  4. Contrast enhanced ultrasound of sentinel lymph nodes

    Directory of Open Access Journals (Sweden)

    XinWu Cui

    2013-03-01

    Full Text Available Sentinel lymph nodes are the first lymph nodes in the region that receive lymphatic drainage from a primary tumor. The detection or exclusion of sentinel lymph node micrometastases is critical in the staging of cancer, especially breast cancer and melanoma because it directly affects patient’s prognosis and surgical management. Currently, intraoperative sentinel lymph node biopsies using blue dye and radioisotopes are the method of choice for the detection of sentinel lymph node with high identification rate. In contrast, conventional ultrasound is not capable of detecting sentinel lymph nodes in most cases. Contrast enhanced ultrasound with contrast specific imaging modes has been used for the evaluation and diagnostic work-up of peripherally located suspected lymphadenopathy. The method allows for real-time analysis of all vascular phases and the visualization of intranodal focal “avascular” areas that represent necrosis or deposits of neoplastic cells. In recent years, a number of animal and human studies showed that contrast enhanced ultrasound can be also used for the detection of sentinel lymph node, and may become a potential application in clinical routine. Several contrast agents have been used in those studies, including albumin solution, hydroxyethylated starch, SonoVue®, Sonazoid® and Definity®. This review summarizes the current knowledge about the use of ultrasound techniques in detection and evaluation of sentinel lymph node.

  5. The role of contrast-enhanced endoscopic ultrasound in pancreatic adenocarcinoma

    DEFF Research Database (Denmark)

    Saftoiu, Adrian; Vilmann, Peter; Bhutani, Manoop S

    2016-01-01

    contrast agents for early detection, tridimensional and fusion techniques for enhanced staging and resectability assessment but also novel applications of perfusion imaging for monitoring ablative therapy, improved local detection through EUS-guided sampling of portal vein flow or enhanced drug delivery......Contrast-enhanced endoscopic ultrasound (CE-EUS) allows characterization, differentiation, and staging of focal pancreatic masses. The method has a high sensitivity and specificity for the diagnosis of pancreatic adenocarcinoma which is visualized as hypo-enhanced as compared to the rest...... of the parenchyma while chronic pancreatitis and neuroendocrine tumors are generally either iso-enhanced or hyper-enhanced. The development of contrast-enhanced low mechanical index harmonic imaging techniques used in real time during endoscopic ultrasound (EUS) allowed perfusion imaging and the quantification...

  6. Fast mutual-information-based contrast enhancement

    Science.gov (United States)

    Cao, Gang; Yu, Lifang; Tian, Huawei; Huang, Xianglin; Wang, Yongbin

    2017-07-01

    Recently, T. Celik proposed an effective image contrast enhancement (CE) method based on spatial mutual information and PageRank (SMIRANK). According to the state-of-the-art evaluation criteria, it achieves the best visual enhancement quality among existing global CE methods. However, SMIRANK runs much slower than the other counterparts, such as histogram equalization (HE) and adaptive gamma correction. Low computational complexity is also required for good CE algorithms. In this paper, we novelly propose a fast SMIRANK algorithm, called FastSMIRANK. It integrates both spatial and gray-level downsampling into the generation of pixel value mapping function. Moreover, the computation of rank vectors is speeded up by replacing PageRank with a simple yet efficient row-based operation of mutual information matrix. Extensive experimental results show that the proposed FastSMIRANK could accelerate the processing speed of SMIRANK by about 20 times, and is even faster than HE. Comparable enhancement quality is preserved simultaneously.

  7. Intraoperative Cerebral Glioma Characterization with Contrast Enhanced Ultrasound

    Directory of Open Access Journals (Sweden)

    Francesco Prada

    2014-01-01

    Full Text Available Background. Contrast enhanced ultrasound (CEUS is a dynamic and continuous modality providing real-time view of vascularization and flow distribution patterns of different organs and tumors. Nevertheless its intraoperative use for brain tumors visualization has been performed few times, and a thorough characterization of cerebral glioma had never been performed before. Aim. To perform the first characterization of cerebral glioma using CEUS and to possibly achieve an intraoperative differentiation of different gliomas. Methods. We performed CEUS in an off-label setting in 69 patients undergoing surgery for cerebral glioma. An intraoperative qualitative analysis was performed comparing iCEUS with B-mode imaging. A postprocedural semiquantitative analysis was then performed for each case, according to EFSUMB criteria. Results were related to histopathology. Results. We observed different CE patterns: LGG show a mild, dotted CE with diffuse appearance and slower, delayed arterial and venous phase. HGG have a high CE with a more nodular, nonhomogeneous appearance and fast perfusion patterns. Conclusion. Our study characterizes for the first time human brain glioma with CEUS, providing further insight regarding these tumors’ biology. CEUS is a fast, safe, dynamic, real-time, and economic tool that might be helpful during surgery in differentiating malignant and benign gliomas and refining surgical strategy.

  8. Topical contrast-enhanced magnetic resonance dacryocystography

    International Nuclear Information System (INIS)

    Yoshikawa, Takeshi; Sugimura, Kazuro; Hirota, Shozo

    2000-01-01

    The purpose of this study was to evaluate the usefulness of magnetic resonance dacryocystography (MRD) with topical administration of normal saline solution and diluted Gd-DTPA solution for the assessment of lacrimal outflow disorders. Two T2-weighted sequences and two T1-weighted sequences were evaluated in this study. The 1:100 diluted Gd solution was prepared by diluting Gd-DTPA (Magnevist) with normal saline solution. A phantom study using tube phantoms of various diameters filled with normal saline solution and 1:100 diluted Gd solution was performed. A preliminary study was performed in ten normal volunteers Eighteen patients with lacrimal outflow disorders underwent clinical MRD, and 14 also underwent conventional dacryocystography (CDG). MRD images were evaluated and compared with clinical symptoms and CDG images. In all sequences, MRD could visualize the full length of 0.7 to 1.7 mm diameter tube phantoms and could show all of the normal lacrimal sacs and nasolacrimal ducts. In the clinical study, MRD findings were compatible with the symptoms in 14 patients but were not compatible with CDG findings in half of the cases. Topical contrast-enhanced MRD provided a simple, non-invasive means of obtaining detailed morphological and functional information on the lacrimal drainage apparatus. (author)

  9. Contrast enhanced ultrasound in liver imaging

    International Nuclear Information System (INIS)

    Nielsen, Michael Bachmann; Bang, Nanna

    2004-01-01

    Ultrasound contrast agents were originally introduced to enhance the Doppler signals when detecting vessels with low velocity flow or when imaging conditions were sub-optimal. Contrast agents showed additional properties, it was discovered that a parenchymal enhancement phase in the liver followed the enhancement of the blood pool. Contrast agents have made ultrasound scanning more accurate in detection and characterization of focal hepatic lesions and the sensitivity is now comparable with CT and MRI scanning. Further, analysis of the transit time of contrast agent through the liver seems to give information on possible hepatic involvement, not only from focal lesions but also from diffuse benign parenchymal disease. The first ultrasound contrast agents were easily destroyed by the energy from the sound waves but newer agents have proved to last for longer time and hereby enable real-time scanning and make contrast enhancement suitable for interventional procedures such as biopsies and tissue ablation. Also, in monitoring the effect of tumour treatment contrast agents have been useful. A brief overview is given on some possible applications and on different techniques using ultrasound contrast agents in liver imaging. At present, the use of an ultrasound contrast agent that allows real-time scanning with low mechanical index is to be preferred

  10. Contrast enhanced ultrasound of splenic lymphoma involvement

    International Nuclear Information System (INIS)

    Goerg, Christian; Faoro, Charis; Bert, Tillmann; Tebbe, Johannes; Neesse, Albrecht; Wilhelm, Christian

    2011-01-01

    Objective: The aim of this study was to compare the value of contrast-enhanced ultrasonography (CEUS) with standard B-mode ultrasound (US) for diagnosis of splenic lymphoma involvement. Methods: From 04/2005 to 10/2008 n = 250 lymphoma patients were investigated by standard B-mode US. A homogeneous splenic echotexture was found in 199 patients (79%). To clarify the benefit of CEUS in this group a pilot series was performed with 16 of the 199 lymphoma patients. All patients with an abnormal splenic echotexture on standard B-Mode US (n = 51) including focal hypoechoic splenic lesions (n = 41) and an inhomogeneous splenic texture (n = 10) were studied by CEUS. CEUS data were retrospectively evaluated. The diagnoses included indolent lymphoma (n = 27), aggressive lymphoma (n = 14), and Hodgkin's disease (n = 10). Number and size of lesions were determined by B-mode US and CEUS. The visualisation of splenic lymphoma involvement by CEUS in comparison to B-mode US was classified as worse, equal, or better. Results: All patients with a homogeneous spleen on B-mode US (n = 16) had no visible focal lesions on CEUS. Study patients with focal lesions (n = 41) had a hypoechoic (n = 22) or isoechoic (n = 19) enhancement during the arterial phase, and a hypoechoic enhancement during the parenchymal phase (n = 41). The visualisation of focal splenic lymphoma was equal (n = 32), better (n = 6), or worse (n = 3). In all study patients with an inhomogeneous spleen on B-mode US (n = 10) no focal lesions were found by CEUS and the value of CEUS therefore was classified as worse. Conclusion: CEUS has no clear advantage for diagnosis of splenic lymphoma involvement.

  11. Contrast enhanced ultrasound of splenic lymphoma involvement

    Energy Technology Data Exchange (ETDEWEB)

    Goerg, Christian, E-mail: goergc@med.uni-marburg.de [Medizinische Universitaetsklinik, Baldingerstrasse, 35033 Marburg/Lahn (Germany); Faoro, Charis [Medizinische Universitaetsklinik, Baldingerstrasse, 35033 Marburg/Lahn (Germany); Bert, Tillmann [Zentralklinik Bad Berka GmbH, Robert-Koch-Allee 9, 99437 Bad Berka (Germany); Tebbe, Johannes [Klinikum Lippe-Detmold, Roentgenstrasse 18, 32756 Detmold (Germany); Neesse, Albrecht; Wilhelm, Christian [Medizinische Universitaetsklinik, Baldingerstrasse, 35033 Marburg/Lahn (Germany)

    2011-11-15

    Objective: The aim of this study was to compare the value of contrast-enhanced ultrasonography (CEUS) with standard B-mode ultrasound (US) for diagnosis of splenic lymphoma involvement. Methods: From 04/2005 to 10/2008 n = 250 lymphoma patients were investigated by standard B-mode US. A homogeneous splenic echotexture was found in 199 patients (79%). To clarify the benefit of CEUS in this group a pilot series was performed with 16 of the 199 lymphoma patients. All patients with an abnormal splenic echotexture on standard B-Mode US (n = 51) including focal hypoechoic splenic lesions (n = 41) and an inhomogeneous splenic texture (n = 10) were studied by CEUS. CEUS data were retrospectively evaluated. The diagnoses included indolent lymphoma (n = 27), aggressive lymphoma (n = 14), and Hodgkin's disease (n = 10). Number and size of lesions were determined by B-mode US and CEUS. The visualisation of splenic lymphoma involvement by CEUS in comparison to B-mode US was classified as worse, equal, or better. Results: All patients with a homogeneous spleen on B-mode US (n = 16) had no visible focal lesions on CEUS. Study patients with focal lesions (n = 41) had a hypoechoic (n = 22) or isoechoic (n = 19) enhancement during the arterial phase, and a hypoechoic enhancement during the parenchymal phase (n = 41). The visualisation of focal splenic lymphoma was equal (n = 32), better (n = 6), or worse (n = 3). In all study patients with an inhomogeneous spleen on B-mode US (n = 10) no focal lesions were found by CEUS and the value of CEUS therefore was classified as worse. Conclusion: CEUS has no clear advantage for diagnosis of splenic lymphoma involvement.

  12. Contrast-enhanced sonography for quantitative assessment of portal hypertension in patients with liver cirrhosis.

    Science.gov (United States)

    Qu, En-Ze; Zhang, Ying-Cai; Li, Zhi-Yan; Liu, Yang; Wang, Jin-Rui

    2014-11-01

    The clinical utility of contrast-enhanced sonography in portal hypertension remains unclear. We explored the feasibility of using contrast-enhanced sonography for noninvasive assessment of portal venous pressure. Twenty healthy individuals (control group; 9 men; mean age, 46.4 years) and 18 patients with portal hypertension (15 men; mean age, 46.2 years) were enrolled in this study. The portal hypertension group included patients who underwent splenectomy and pericardial blood vessel disarticulation at our hospital from October 2010 to March 2011. One week before surgery, patients with portal hypertension underwent preoperative liver contrast-enhanced sonography. Two-dimensional, Doppler, and contrast-enhanced sonographic parameters were compared between the groups. Portal venous pressure was measured intraoperatively by portal vein puncture in the portal hypertension group, and its relationship with the other parameters was analyzed. The 2-dimensional, Doppler, and contrast-enhanced sonographic parameters differed between the groups (P Portal venous pressure was inversely correlated with the area under the portal vein/hepatic artery time-intensity curve ratio (Qp/Qa), portal vein/hepatic artery strength ratio (Ip/Ia), and portal vein/hepatic artery wash-in perfusion slope ratio (βp/βa), with correlation coefficients of -0.701, -0.625, and -0.494, respectively. Measurement of the liver contrast-enhanced sonographic parameters Qp/Qa, Ip/Ia, and βp/βa could be used as a new quantitative method for noninvasively assessing portal venous pressure. © 2014 by the American Institute of Ultrasound in Medicine.

  13. Characterization of Enhancing MS Lesions by Dynamic Texture Parameter Analysis of Dynamic Susceptibility Perfusion Imaging

    Directory of Open Access Journals (Sweden)

    Rajeev K. Verma

    2016-01-01

    Full Text Available Purpose. The purpose of this study was to investigate statistical differences with MR perfusion imaging features that reflect the dynamics of Gadolinium-uptake in MS lesions using dynamic texture parameter analysis (DTPA. Methods. We investigated 51 MS lesions (25 enhancing, 26 nonenhancing lesions of 12 patients. Enhancing lesions (n=25 were prestratified into enhancing lesions with increased permeability (EL+; n=11 and enhancing lesions with subtle permeability (EL−; n=14. Histogram-based feature maps were computed from the raw DSC-image time series and the corresponding texture parameters were analyzed during the inflow, outflow, and reperfusion time intervals. Results. Significant differences (p<0.05 were found between EL+ and EL− and between EL+ and nonenhancing inactive lesions (NEL. Main effects between EL+ versus EL− and EL+ versus NEL were observed during reperfusion (mainly in mean and standard deviation (SD: EL+ versus EL− and EL+ versus NEL, while EL− and NEL differed only in their SD during outflow. Conclusion. DTPA allows grading enhancing MS lesions according to their perfusion characteristics. Texture parameters of EL− were similar to NEL, while EL+ differed significantly from EL− and NEL. Dynamic texture analysis may thus be further investigated as noninvasive endogenous marker of lesion formation and restoration.

  14. Cerebral perfusion MR imaging using FAIR-HASTE in chronic carotid occlusive disease. Comparison with dynamic susceptibility contrast-perfusion MR imaging

    International Nuclear Information System (INIS)

    Ida, Kentaro; Akaki, Shiro; Sei, Tetsuro; Kanazawa, Susumu; Tsunoda, Masatoshi

    2006-01-01

    To determine the efficacy of flow-sensitive alternating inversion recovery using half-Fourier single-shot turbo spin-echo (FAIR-HASTE) in detecting cerebral hypoperfusion in chronic carotid occlusive disease, we subjected 12 patients with various degrees of cervical internal carotid artery stenoses and/or occlusion (Stenosis group) and 24 volunteers (Normal group) to FAIR-HASTE. In addition, 10 out of 12 patients in the Stenosis group underwent dynamic susceptibility contrast-perfusion magnetic resonance imaging (DSC-pMRI) before and after revascularization in the dominantly affected side. The absolute asymmetry indexes (AIs) of both cerebral hemispheres in the Normal and Stenosis groups were compared in FAIR-HASTE. In addition, the AIs were compared with those in the Stenosis group before and after revascularization in both FAIR-HASTE and regional cerebral blood flow (rCBF), calculated with DSC-pMRI. A statistically significant difference was recognized between the AIs in the Normal and Stenosis groups (AI=2.25±1.92, 8.09±4.60, respectively; p<0.0001). Furthermore, in the Stenosis group the AIs on both FAIR-HASTE (8.88±4.93, 2.22±1.79, respectively; p=0.0003) and rCBF (7.13±3.57, 1.25±1.33, respectively; p=0.0003) significantly decreased after revascularization. In the Stenosis group, before revascularization, signal intensity on both FAIR-HASTE and rCBF had a tendency to be lower in the dominantly affected side. FAIR-HASTE imaging was useful in the detection and evaluation of cerebral hypoperfusion in chronic occlusive carotid disease. (author)

  15. The advantage of high relaxivity contrast agents in brain perfusion

    International Nuclear Information System (INIS)

    Cotton, F.; Hermier, M.

    2006-01-01

    Accurate MRI characterization of brain lesions is critical for planning therapeutic strategy, assessing prognosis and monitoring response to therapy. Conventional MRI with gadolinium-based contrast agents is useful for the evaluation of brain lesions, but this approach primarily depicts areas of disruption of the blood-brain barrier (BBB) rather than tissue perfusion. Advanced MR imaging techniques such as dynamic contrast agent-enhanced perfusion MRI provide physiological information that complements the anatomic data available from conventional MRI. We evaluated brain perfusion imaging with gadobenate dimeglumine (Gd-BOPTA, MultiHance; Bracco Imaging, Milan, Italy). The contrast-enhanced perfusion technique was performed on a Philips Intera 1.5-T MR system. The technique used to obtain perfusion images was dynamic susceptibility contrast-enhanced MRI, which is highly sensitive to T2* changes. Combined with PRESTO perfusion imaging, SENSE is applied to double the temporal resolution, thereby improving the signal intensity curve fit and, accordingly, the accuracy of the derived parametric images. MultiHance is the first gadolinium MR contrast agent with significantly higher T1 and T2 relaxivities than conventional MR contrast agents. The higher T1 relaxivity, and therefore better contrast-enhanced T1-weighted imaging, leads to significantly improved detection of BBB breakdown and hence improved brain tumor conspicuity and delineation. The higher T2 relaxivity allows high-quality T2*-weighted perfusion MRI and the derivation of good quality relative cerebral blood volume (rCBV) maps. We determined the value of MultiHance for enhanced T2*-weighted perfusion imaging of histologically proven (by surgery or stereotaxic biopsy) intraaxial brain tumors (n=80), multiple sclerosis lesions (n=10), abscesses (n=4), neurolupus (n=15) and stroke (n=16). All the procedures carried out were safe and no adverse events occurred. The acquired perfusion images were of good quality in

  16. Preliminary study of single contrast enhanced dual energy heart imaging using dual-source CT

    International Nuclear Information System (INIS)

    Peng Jin; Zhang Longjiang; Zhou Changsheng; Lu Guangming; Ma Yan; Gu Haifeng

    2009-01-01

    Objective: To evaluate the feasibility and preliminary applications of single contrast enhanced dual energy heart imaging using dual-source CT (DSCT). Methods: Thirty patients underwent dual energy heart imaging with DSCT, of which 6 cases underwent SPECT or DSA within one week. Two experienced radiologists assessed image quality of coronary arteries and iodine map of myocardium. and correlated the coronary artery stenosis with the perfusion distribution of iodine map. Results: l00% (300/300) segments reached diagnostic standards. The mean score of image for all patients was 4.68±0.57. Mural coronary artery was present in 10 segments in S cases, atherosclerotic plaques in 32 segments in 12 cases, of which 20 segments having ≥50% stenosis, 12 segments ≤50% stenosis; dual energy CT coronary angiography was consistent with the DSA in 3 patients. 37 segmental perfusion abnormalities on iodine map were found in 15 cases, including 28 coronary blood supply segment narrow segment and 9 no coronary stenosis (including three negative segments in SPECD. Conclusion: Single contrast enhanced dual energy heart imaging can provide good coronary artery and myocardium perfusion images in the patients with appropriate heart rate, which has a potential to be used in the clinic and further studies are needed. (authors)

  17. Is contrast-enhanced CT indicated in acute head injury

    International Nuclear Information System (INIS)

    Mauser, H.W.; Nieuwenhuizen, O. van; Veiga-Pires, J.A.

    1984-01-01

    The authors discuss the value of intravenous contrast enhancement in CT scanning in acute head injury. In a series of seventy consecutive patients they conclude that no incremental information was obtained by performing contrast-enhanced CT scans in the acute phase of the head injury. (orig.)

  18. A contrast-enhanced ultrasound study of benign and malignant ...

    African Journals Online (AJOL)

    A contrast-enhanced ultrasound study of benign and malignant breast tissue. S Barnard, E Leen, T Cooke, W Angerson. Abstract. Objective. To determine the diagnostic value of haemodynamic contrast-enhanced ultrasound assessment in benign and malignant breast tissue, using histological examination as the reference ...

  19. Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

    International Nuclear Information System (INIS)

    Xu Huixiong; Chen Lida; Xie Xiaoyan; Xie Xiaohua; Xu Zuofeng; Liu Guangjian; Lin Manxia; Wang Zhu; Lu Mingde

    2010-01-01

    Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated. Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125). Conclusion: The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.

  20. Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Xu Huixiong, E-mail: xuhuixiong@hotmail.co [Department of Medical Ultrasonics, The First Affiliated Hospital, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou 510080 (China); Chen Lida; Xie Xiaoyan; Xie Xiaohua; Xu Zuofeng; Liu Guangjian; Lin Manxia; Wang Zhu [Department of Medical Ultrasonics, The First Affiliated Hospital, Institute of Diagnostic and Interventional Ultrasound, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou 510080 (China); Lu Mingde, E-mail: lumd@21cn.co [Department of Hepatobiliary Surgery, First Affiliated Hospital, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou 510080 (China)

    2010-08-15

    Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated. Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125). Conclusion: The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.

  1. Contrast-enhanced spectral mammography (CESM) and contrast enhanced MRI (CEMRI): Patient preferences and tolerance.

    Science.gov (United States)

    Hobbs, Max M; Taylor, Donna B; Buzynski, Sebastian; Peake, Rachel E

    2015-06-01

    Contrast-enhanced spectral mammography (CESM) may have similar diagnostic performance to Contrast-enhanced MRI (CEMRI) in the diagnosis and staging of breast cancer. To date, research has focused exclusively on diagnostic performance when comparing these two techniques. Patient experience is also an important factor when comparing and deciding on which of these modalities is preferable. The aim of this study is to compare patient experience of CESM against CEMRI during preoperative breast cancer staging. Forty-nine participants who underwent both CESM and CEMRI, as part of a larger trial, completed a Likert questionnaire about their preference for each modality according to the following criteria: comfort of breast compression, comfort of intravenous (IV) contrast injection, anxiety and overall preference. Participants also reported reasons for preferring one modality to the other. Quantitative data were analysed using a Wilcoxon sign-rank test and chi-squared test. Qualitative data are reported descriptively. A significantly higher overall preference towards CESM was demonstrated (n = 49, P < 0.001), with faster procedure time, greater comfort and lower noise level cited as the commonest reasons. Participants also reported significantly lower rates of anxiety during CESM compared with CEMRI (n = 36, P = 0.009). A significantly higher rate of comfort was reported during CEMRI for measures of breast compression (n = 49, P = 0.001) and the sensation of IV contrast injection (n = 49, P = 0.003). Our data suggest that overall, patients prefer the experience of CESM to CEMRI, adding support for the role of CESM as a possible alternative to CEMRI for breast cancer staging. © 2015 The Royal Australian and New Zealand College of Radiologists.

  2. Contrast-enhanced spectral mammography (CESM) and contrast enhanced MRI (CEMRI): Patient preferences and tolerance

    International Nuclear Information System (INIS)

    Hobbs, Max; Buzynski, Sebastian; Taylor, Donna B.; Peake, Rachel E.

    2015-01-01

    Contrast-enhanced spectral mammography (CESM) may have similar diagnostic performance to Contrast-enhanced MRI (CEMRI) in the diagnosis and staging of breast cancer. To date, research has focused exclusively on diagnostic performance when comparing these two techniques. Patient experience is also an important factor when comparing and deciding on which of these modalities is preferable. The aim of this study is to compare patient experience of CESM against CEMRI during preoperative breast cancer staging. Forty-nine participants who underwent both CESM and CEMRI, as part of a larger trial, completed a Likert questionnaire about their preference for each modality according to the following criteria: comfort of breast compression, comfort of intravenous (IV) contrast injection, anxiety and overall preference. Participants also reported reasons for preferring one modality to the other. Quantitative data were analysed using a Wilcoxon sign-rank test and chi-squared test. Qualitative data are reported descriptively. A significantly higher overall preference towards CESM was demonstrated (n = 49, P < 0.001), with faster procedure time, greater comfort and lower noise level cited as the commonest reasons. Participants also reported significantly lower rates of anxiety during CESM compared with CEMRI (n = 36, P = 0.009). A significantly higher rate of comfort was reported during CEMRI for measures of breast compression (n = 49, P = 0.001) and the sensation of IV contrast injection (n = 49, P = 0.003). Our data suggest that overall, patients prefer the experience of CESM to CEMRI, adding support for the role of CESM as a possible alternative to CEMRI for breast cancer staging.

  3. Contrast Enhanced Ultrasound of the Kidneys: What Is It Capable of?

    Directory of Open Access Journals (Sweden)

    Demosthenes D. Cokkinos

    2013-01-01

    Full Text Available One of the many imaging uses of contrast enhanced ultrasound (CEUS is studying a wide variety of kidney pathology, due to its ability to detect microvascular blood flow in real time without affecting renal function. CEUS enables dynamic assessment and quantification of microvascularisation up to capillary perfusion. The objective of this paper is to briefly refresh basic knowledge of ultrasound (US contrast agents’ physical properties, to study technical details of CEUS scanning in the kidneys, and to review the commonest renal indications for CEUS, with imaging examples in comparison to baseline unenhanced US and computed tomography when performed. Safety matters and limitations of CEUS of the kidneys are also discussed.

  4. High-resolution blood-pool-contrast-enhanced MR angiography in glioblastoma: tumor-associated neovascularization as a biomarker for patient survival. A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Puig, Josep; Blasco, Gerard; Remollo, Sebastian; Hernandez, David; Pedraza, Salvador [Hospital Universitari Dr Josep Trueta, Research Unit of Diagnostic Imaging Institute (IDI), Department of Radiology [Girona Biomedical Research Institute] IDIBGI, Girona (Spain); Daunis-i-Estadella, Josep; Mateu, Gloria [University of Girona, Department of Computer Science, Applied Mathematics and Statistics, Girona (Spain); Alberich-Bayarri, Angel [La Fe Polytechnics and University Hospital, Biomedical Imaging Research Group (GIBI230), La Fe Health Research Institute, Valencia (Spain); Essig, Marco [University of Manitoba, Department of Radiology, Winnipeg (Canada); Jain, Rajan [NYU School of Medicine, Division of Neuroradiology, Department of Radiology, New York, NY (United States); Puigdemont, Montserrat [Hospital Universitari Dr Josep Trueta, Catalan Institute of Oncology (ICO), Hospital Cancer Registry, Girona (Spain); Sanchez-Gonzalez, Javier [Philips Healthcare Iberica, Madrid (Spain); Wintermark, Max [Stanford University, Department of Radiology, Neuroradiology Division, Palo Alto, CA (United States)

    2016-01-15

    The objective of the study was to determine whether tumor-associated neovascularization on high-resolution gadofosveset-enhanced magnetic resonance angiography (MRA) is a useful biomarker for predicting survival in patients with newly diagnosed glioblastomas. Before treatment, 35 patients (25 men; mean age, 64 ± 14 years) with glioblastoma underwent MRI including first-pass dynamic susceptibility contrast (DSC) perfusion and post-contrast T1WI sequences with gadobutrol (0.1 mmol/kg) and, 48 h later, high-resolution MRA with gadofosveset (0.03 mmol/kg). Volumes of interest for contrast-enhancing lesion (CEL), non-CEL, and contralateral normal-appearing white matter were obtained, and DSC perfusion and DWI parameters were evaluated. Prognostic factors were assessed by Kaplan-Meier survival and Cox proportional hazards model. Eighteen (51.42 %) glioblastomas were hypervascular on high-resolution MRA. Hypervascular glioblastomas were associated with higher CEL volume and lower Karnofsky score. Median survival rates for patients with hypovascular and hypervascular glioblastomas treated with surgery, radiotherapy, and chemotherapy were 15 and 9.75 months, respectively (P < 0.001). Tumor-associated neovascularization was the best predictor of survival at 5.25 months (AUC = 0.794, 81.2 % sensitivity, 77.8 % specificity, 76.5 % positive predictive value, 82.4 % negative predictive value) and yielded the highest hazard ratio (P < 0.001). Tumor-associated neovascularization detected on high-resolution blood-pool-contrast-enhanced MRA of newly diagnosed glioblastoma seems to be a useful biomarker that correlates with worse survival. (orig.)

  5. Contrast-enhanced MR angiography in Leriche's syndrome

    International Nuclear Information System (INIS)

    Link, J.; Steffens, J.C.; Brossmann, J.; Heller, M.; Loose, R.

    1998-01-01

    Purpose: To determine the usefulness of contrast-enhanced MR angiography for the diagnosis of Leriche's syndrome. Material and methods: Leriche's syndrome was seen in 7 patients via DSA. In [dition, contrast-enhanced MR angiography was performed (T R 7.8 ms/T E 2.1 ms, flip angle 30 , slab thickness 116 mm, slice thickness 1.82 mm, 64 partitions, FOV 500x438 mm, matrix 224x512). Results: Diagnosis of Leriche's syndrome was possible by contrast-enhanced MR angiography in each case. Visualisation of the femoral arteries was not possible in two patients by intraarterial DSA, in three other patients there was an insufficient contrast in the femoral arteries with DSA. Contrast-enhanced MR angiography revealed good visualisation of the femoral arteries in these patients. In [dition, contrast-enhanced MR angiography allowed complete visualisation of the patent lower limb arteries. In intraarterial DSA visualisation of the lower limb arteries was achieved reached in only one patient, but was incomplete. Conclusion: Contrast-enhanced MR angiography yielded the correct diagnosis of Leriche's syndrome in all 7 patients. Contrast-enhanced MR angiography was superior to DSA in the assessment of the distal run-off vessels in five of seven patients. (orig.) [de

  6. Simulation-based comparison of two approaches frequently used for dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Zwick, Stefan; Brix, Gunnar; Tofts, Paul S.; Strecker, Ralph; Kopp-Schneider, Annette; Laue, Hendrik; Semmler, Wolfhard; Kiessling, Fabian

    2010-01-01

    The purpose was to compare two approaches for the acquisition and analysis of dynamic-contrast-enhanced MRI data with respect to differences in the modelling of the arterial input-function (AIF), the dependency of the model parameters on physiological parameters and their numerical stability. Eight hundred tissue concentration curves were simulated for different combinations of perfusion, permeability, interstitial volume and plasma volume based on two measured AIFs and analysed according to the two commonly used approaches. The transfer constants (Approach 1) K trans and (Approach 2) k ep were correlated with all tissue parameters. K trans showed a stronger dependency on perfusion, and k ep on permeability. The volume parameters (Approach 1) v e and (Approach 2) A were mainly influenced by the interstitial and plasma volume. Both approaches allow only rough characterisation of tissue microcirculation and microvasculature. Approach 2 seems to be somewhat more robust than 1, mainly due to the different methods of CA administration. (orig.)

  7. Contrast-enhanced ultrasonography for the determination of Crohn’s disease activity – preliminary experience

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Summary Background Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn’s disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Material/Methods Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Results Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. Conclusions CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn’s disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI. PMID:24723988

  8. Contrast-enhanced ultrasonography for the determination of Crohn's disease activity - preliminary experience.

    Science.gov (United States)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn's disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn's disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI.

  9. Contrast-enhanced ultrasonography for the determination of Crohn’s disease activity – preliminary experience

    International Nuclear Information System (INIS)

    Białecki, Marcin; Białecka, Agnieszka; Laskowska, Katarzyna; Kłopocka, Maria; Liebert, Ariel; Lemanowicz, Adam; Serafin, Zbigniew

    2014-01-01

    Contrast-enhanced ultrasound (CEUS) is a recent non-invasive modality, which may partially replace currently used techniques (endoscopy, CT enterography and MR enterography) in the diagnostics and assessment of Crohn’s disease (CD). The aim of the study was to analyze early experience in the use of CEUS for the measurement of activity and staging of CD. Eleven patients previously diagnosed with CD were included in the study. They underwent contrast-enhanced ultrasonography (SonoVue, Bracco), low-dose CT enterography (LDCTE), assessment of laboratory markers of inflammation and clinical CD activity index (CDAI). Contrast enhancement was evaluated using a semi-quantitative method and a quantitative method that included measurement of peak enhancement (PE), enhancement curve rise time (RT) and wash-in-rate (WiR). Ileal wall thickening was observed in all patients. Semi-quantitative method was used to observe CD activity in CEUS in 10 cases that perfectly matched LDCTE findings. There was a moderate positive correlation between PE and CDAI (r=0.65, p<0.001). There was no significant relationship between perfusion parameters and laboratory markers of inflammation. CEUS is a promising modality for non-invasive assessment of pathologic ileal vascularization in the course of Crohn’s disease. Intensity of enhancement in CEUS reflects activity of the disease detected in LDCTE and correlates with CDAI

  10. Potential Cost Savings of Contrast-Enhanced Digital Mammography.

    Science.gov (United States)

    Patel, Bhavika K; Gray, Richard J; Pockaj, Barbara A

    2017-06-01

    The purpose of this article is to discuss whether the sensitivity and specificity of contrast-enhanced digital mammography (CEDM) render it a viable diagnostic alternative to breast MRI. That CEDM couples low-energy images (comparable to the diagnostic quality of standard mammography) and subtracted contrast-enhanced mammograms make it a cost-effective modality and a realistic substitute for the more costly breast MRI.

  11. Dual-energy contrast-enhanced spectral mammography (CESM).

    Science.gov (United States)

    Daniaux, Martin; De Zordo, Tobias; Santner, Wolfram; Amort, Birgit; Koppelstätter, Florian; Jaschke, Werner; Dromain, Clarisse; Oberaigner, Willi; Hubalek, Michael; Marth, Christian

    2015-10-01

    Dual-energy contrast-enhanced mammography is one of the latest developments in breast care. Imaging with contrast agents in breast cancer was already known from previous magnetic resonance imaging and computed tomography studies. However, high costs, limited availability-or high radiation dose-led to the development of contrast-enhanced spectral mammography (CESM). We reviewed the current literature, present our experience, discuss the advantages and drawbacks of CESM and look at the future of this innovative technique.

  12. The use of contrast-enhanced post Mortem CT in the detection of cardiovascular deaths.

    Directory of Open Access Journals (Sweden)

    Jonas Christoph Apitzsch

    Full Text Available OBJECTIVES: To evaluate the diagnostic value of contrast enhanced post mortem computed tomography (PMCT in comparison to non-enhanced post mortem CT in the detection of cardiovascular causes of death (COD. BACKGROUND: As autopsy rates decline, new methods to determine CODs are necessary. So contrast enhanced PMCT shall be evaluated in comparison to established non-enhanced PMCT in order to further improve the method. METHODS: In a prospective study, 20 corpses were examined using a 64-row multisclice CT (MSCT before and after intraarterial perfusion with a newly developed, barium-bearing contrast agent and ventilation of the lungs. The cause of death was determined in enhanced and unenhanced scans and a level of confidence (LOC was given by three experienced radiologists on a scale between 0 and 4. Results were compared to autopsy results as gold standard. Autopsy was performed blinded to PMCT-findings. RESULTS: The method allowed visualization of different types of cause of death. There was a significant improvement in LOC in enhanced scans compared to unenhanced scans as well as an improvement in the detection of COD. The cause of death could be determined in 19 out of 20 patients. CONCLUSIONS: PMCT is feasible and appears to be robust for diagnosing cardiovascular causes of death. When compared with unenhanced post-mortem CT intraarterial perfusion and pulmonary ventilation significantly improve visualization and diagnostic accuracy. These promising results warrant further studies.

  13. Evaluation of sacroiliitis: contrast-enhanced MRI with subtraction technique

    Energy Technology Data Exchange (ETDEWEB)

    Algin, Oktay; Gokalp, Gokhan; Baran, Bulent; Ocakoglu, Gokhan; Yazici, Zeynep [Uludag University, Medical Faculty, Department of Radiology, Gorukle, Bursa (Turkey)

    2009-10-15

    The purpose of the study was to investigate the diagnostic value of contrast-enhanced MRI using the subtraction technique in the detection of active sacroiliitis. Magnetic resonance imaging was performed in 8 asymptomatic volunteers and 50 patients with clinically suspected active sacroiliitis. On precontrast MR images, T1-weighted spin-echo images with and without fat saturation (T1WFS and T1W), STIR and 3D-FLASH images with fat saturation were obtained in the semicoronal plane using a 1.5 Tesla imager. Postcontrast MRI was performed using the same T1WFS sequence as before contrast injection for all volunteers and patients. Postcontrast images were subtracted from fat-suppressed precontrast images. Enhancement within the joint space and bone marrow was considered to demonstrate active sacroiliitis. In 50 patients (100 sacroiliac joints [SIJs]), 40 (76 SIJs) were considered to have active sacroiliitis based on MR images. Bone marrow edema was present in 33 patients (62 SIJs) on STIR images. Routine MRI allowed identification of contrast enhancement in SIJs on postcontrast T1WFS images in 31 patients (49 SIJs). Contrast enhancement was observed in 40 patients (76 SIJs) who were examined by MRI using the subtraction technique. Contrast enhancement was significantly more conspicuous on subtraction images than on non-subtracted postcontrast T1WFS images (Mann-Whitney U test, p<0.001). Contrast-enhanced MRI with subtraction technique may be useful for early detection of active sacroiliitis. (orig.)

  14. Contrast-enhanced CISS imaging of cerebellopontine angle tumors

    Energy Technology Data Exchange (ETDEWEB)

    Tozaki, Mitsuhiro; Toyoda, Keiko; Hata, Yuichi; Fukuda, Yasushi; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine; Katano, Shuichi

    1999-10-01

    Our purpose of this study was to evaluate the clinical usefulness of contrast-enhanced CISS-3DFT MR imaging for the diagnosis of CP angle tumors. CISS-3DFT MR imaging is expected for screening procedure of acoustic schwannoma because of excellent spatial resolution. Recently, we discovered contrast enhancement effect on CISS sequence in spite of heavily T{sub 2}-weighted images. Fourteen patients with CP angle tumors were performed on a 1.0 T MR unit. Transaxial CISS-3DFT MRI was obtained both before and after intravenous injections of Gd-DTPA. Multiplanar reconstructions (MPRs) were performed in all cases. Contrast enhancement effect of CP angle tumors, and the relationship between tumors and the adjacent cranial nerves were evaluated. Contrast enhancement effect of the tumors was present in all cases in spite of heavily T{sub 2}-weighted images of CISS sequences. In the internal auditory canal, relationship between the tumors and the cranial nerves was demonstrated in 6 cases (6/9). In the cerebellopontine cistern, all cases were demonstrated (11/11). Contrast-enhanced CISS-3DFT MR imaging with a good contrast resolution and an excellent spatial resolution is useful for the diagnosis of CP angle tumors. (author)

  15. Three-dimensional black-blood contrast-enhanced MRI improves detection of intraluminal thrombi in patients with acute ischaemic stroke.

    Science.gov (United States)

    Jang, Won; Kwak, Hyo Sung; Chung, Gyung Ho; Hwang, Seung Bae

    2018-03-19

    This study evaluated the utility of three-dimensional (3D), black-blood (BB), contrast-enhanced, magnetic resonance imaging (MRI) for the detection of intraluminal thrombi in acute stroke patients. Forty-seven patients with acute stroke involving the anterior circulation underwent MRI examination within 6 h of clinical onset. Cerebral angiography was used as the reference standard. In a blinded manner, two neuroradiologists interpreted the following three data sets: (1) diffusion-weighted imaging (DWI) + 3D BB contrast-enhanced MRI; (2) DWI + susceptibility weighted imaging (SWI); (3) DWI + 3D BB contrast-enhanced MRI + SWI. Of these patients, 47 had clots in the middle cerebral artery and four had clots in the anterior cerebral artery. For both observers, the area under the curve (Az) for data sets 1 and 3, which included 3D BB contrast-enhanced MRI, was significantly greater than it was for data set 2, which did not include 3D BB contrast-enhanced MR imaging (observer 1, 0.988 vs 0.904, p = 0.001; observer 2, 0.988 vs 0.894, p = 0.000). Three-dimensional BB contrast-enhanced MRI improves detection of intraluminal thrombi compared to conventional MRI methods in patients with acute ischaemic stroke. • BB contrast-enhanced MRI helps clinicians to assess the intraluminal clot • BB contrast-enhanced MRI improves detection of intraluminal thrombi • BB contrast-enhanced MRI for clot detection has a higher sensitivity.

  16. Sentinel node detection in melanomas using contrast-enhanced ultrasound

    DEFF Research Database (Denmark)

    Nielsen, K. Rue; Klyver, H.; Chakera, A. Hougaard

    2009-01-01

    in humans. PURPOSE: To investigate the possible use of CEUS in detecting SN in patients with malignant melanomas (MM), and to improve the method by using different concentrations of contrast agent and various positions of the extremity. MATERIAL AND METHODS: Ten patients with MM on an extremity and one...... healthy volunteer were included. One milliliter of a contrast agent (Sonovue; Bracco, Milan, Italy) was injected subcutaneously on both sides of the scar from the excised tumor. Contrast-enhanced lymph channels and lymph nodes (LNs) were searched for using low-mechanical-index CEUS and by stimulated...... tissue damage, as the contrast agent was not registered for subcutaneous administration. RESULTS: In one patient, two contrast-enhanced inguinal LNs were visualized by CEUS, corresponding to two inguinal SNs found by scintigraphic imaging. No contrast-enhanced lymph channels or LNs were visualized in any...

  17. A case report of pseudoprogression followed by complete remission after proton-beam irradiation for a low-grade glioma in a teenager: the value of dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Meyzer, Candice; Dhermain, Frédéric; Ducreux, Denis; Habrand, Jean-Louis; Varlet, Pascale; Sainte-Rose, Christian; Dufour, Christelle; Grill, Jacques

    2010-01-01

    A fourteen years-old boy was treated post-operatively with proton therapy for a recurrent low-grade oligodendroglioma located in the tectal region. Six months after the end of irradiation (RT), a new enhancing lesion appeared within the radiation fields. To differentiate disease progression from radiation-induced changes, dynamic susceptibility contrast-enhanced (DSCE) MRI was used with a T2* sequence to study perfusion and permeability characteristics simultaneously. Typically, the lesion showed hypoperfusion and hyperpermeability compared to the controlateral normal brain. Without additional treatment but a short course of steroids, the image disappeared over a six months period allowing us to conclude for a pseudo-progression. The patient is alive in complete remission more than 2 years post-RT

  18. Contrast-enhanced CMR in patients after percutaneous closure of the left atrial appendage: A pilot study

    Directory of Open Access Journals (Sweden)

    Petersen Steffen E

    2011-07-01

    Full Text Available Abstract Background To evaluate the feasibility and value of first-pass contrast-enhanced dynamic and post-contrast 3D CMR in patients after transcatheter occlusion of left atrial appendage (LAA to identify incorrect placement and persistent leaks. Methods 7 patients with different occluder systems (n = 4 PLAATO; n = 2 Watchman; n = 1 ACP underwent 2 contrast-enhanced (Gd-DOTA CMR sequences (2D TrueFISP first-pass perfusion and 3D-TurboFLASH to assess localization, artifact size and potential leaks of the devices. Perfusion CMR was analyzed visually and semi-quantitatively to identify potential leaks. Results All occluders were positioned within the LAA. The ACP occluder presented the most extensive artifact size. Visual assessment revealed a residual perfusion of the LAA apex in 4 cases using first-pass perfusion and 3D-TurboFLASH indicating a suboptimal LAA occlusion. By assessing signal-to-time-curves the cases with a visually detected leak showed a 9-fold higher signal-peak in the LAA apex (567 ± 120% increase from baseline signal than those without a leak (61 ± 22%; p Conclusion This CMR pilot study provides valuable non-invasive information in patients after transcatheter occlusion of the LAA to identify correct placement and potential leaks. We recommend incorporating CMR in future clinical studies to evaluate new device types.

  19. Intraoperative contrast-enhanced ultrasonography for microcirculatory evaluation in rhesus monkey with spinal cord injury.

    Science.gov (United States)

    Huang, Lin; Chen, Keng; Chen, Fu-Chao; Shen, Hui-Yong; Ye, Ji-Chao; Cai, Zhao-Peng; Lin, Xi

    2017-06-20

    This study tried to quantify spinal cord perfusion by using contrast-enhanced ultrasound (CEUS) in rhesus monkey models with acute spinal cord injury. Acute spinal cord perfusion after injury was detected by CEUS, coupling with conventional ultrasound (US) and Color Doppler US (CDFI). Time-intensity curves and perfusion parameters were obtained by autotracking contrast quantification (ACQ) software in the epicenter and adjacent regions of injury, respectively. Neurological and histological examinations were performed to confirm the severity of injury. US revealed spinal cords were hypoechoic and homogeneous, whereas dura maters, pia maters, and cerebral aqueducts were hyperechoic. After spinal cord contusion, the injured spinal cord was hyperechoic on US, and intramedullary vessels of adjacent region of injury were increased and dilated on CDFI. On CEUS hypoperfusion were found in the epicenter of injury, while hyperperfusion in its adjacent region. Quantitative analysis showed that peak intensity (PI) decreased in epicenters of injury but significantly increased in adjacent regions at all time points (p spinal cord injury in overall views and real-time.

  20. Influence of ageing on quantitative contrast-enhanced ultrasound of the kidneys in healthy cats.

    Science.gov (United States)

    Stock, Emmelie; Paepe, Dominique; Daminet, Sylvie; Duchateau, Luc; Saunders, Jimmy H; Vanderperren, Katrien

    2018-05-05

    The degenerative effects of ageing on the kidneys have been extensively studied in humans. However, only recently interest has been focused on renal ageing in veterinary medicine. Contrast-enhanced ultrasound allows non-invasive evaluation of renal perfusion in conscious cats. Renal perfusion parameters were obtained in 43 healthy cats aged 1-16 years old, and the cats were divided in four age categories: 1-3 years, 3-6 years, 6-10 years and over 10 years. Routine renal parameters as serum creatinine, serum urea, urine-specific gravity, urinary protein:creatinine ratio and systolic blood pressure were also measured. No significant differences in any of the perfusion parameters were observed among the different age categories. A trend towards a lower peak enhancement and wash-in area under the curve with increasing age, suggestive for a lower blood volume, was detected when comparing the cats over 10 years old with the cats of 1-3 years old. Additionally, no significant age-effect was observed for the serum and urine parameters, whereas a higher blood pressure was observed in healthy cats over 10 years old. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. A Novel Contrast Enhancement Technique on Palm Bone Images

    Directory of Open Access Journals (Sweden)

    Yung-Tsang Chang

    2014-09-01

    Full Text Available Contrast enhancement plays a fundamental role in image processing. Many histogram-based techniques are widely used for contrast enhancement of given images, due to their simple function and effectiveness. However, the conventional histogram equalization (HE methods result in excessive contrast enhancement, which causes natural looking and satisfactory results for a variety of low contrast images. To solve such problems, a novel multi-histogram equalization technique is proposed to enhance the contrast of the palm bone X-ray radiographs in this paper. For images, the mean-variance analysis method is employed to partition the histogram of the original grey scale image into multiple sub-histograms. These histograms are independently equalized. By using this mean-variance partition method, a proposed multi-histogram equalization technique is employed to achieve the contrast enhancement of the palm bone X-ray radiographs. Experimental results show that the multi-histogram equalization technique achieves a lower average absolute mean brightness error (AMBE value. The multi-histogram equalization technique simultaneously preserved the mean brightness and enhanced the local contrast of the original image.

  2. Reproducibility of contrast-enhanced transrectal ultrasound of the prostate

    NARCIS (Netherlands)

    Sedelaar, J. P.; Goossen, T. E.; Wijkstra, H.; de la Rosette, J. J.

    2001-01-01

    Transrectal three-dimensional (3-D) contrast-enhanced power Doppler ultrasound (US) is a novel technique for studying possible prostate malignancy. Before studies can be performed to investigate the clinical validity of the technique, reproducibility of the contrast US studies must be proven.

  3. Dynamic contrast-enhanced MRI of the prostate. Comparison of two different post-processing algorithms

    International Nuclear Information System (INIS)

    Beyersdorff, Dirk; Franiel, T.; Luedemann, L.; Dietz, E.; Galler, D.; Marchot, P.

    2011-01-01

    Purpose: To evaluate the usefulness of a commercially available post-processing software tool for detecting prostate cancer on dynamic contrast-enhanced magnetic resonance imaging (MRI) and to compare the results to those obtained with a custom-made post-processing algorithm already tested under clinical conditions. Materials and Methods: Forty-eight patients with proven prostate cancer were examined by standard MRI supplemented by dynamic contrast-enhanced dual susceptibility contrast (DCE-DSC) MRI prior to prostatectomy. A custom-made post-processing algorithm was used to analyze the MRI data sets and the results were compared to those obtained using a post-processing algorithm from Invivo Corporation (Dyna CAD for Prostate) applied to dynamic T 1-weighted images. Histology was used as the gold standard. Results: The sensitivity for prostate cancer detection was 78 % for the custom-made algorithm and 60 % for the commercial algorithm and the specificity was 79 % and 82 %, respectively. The accuracy was 79 % for our algorithm and 77.5 % for the commercial software tool. The chi-square test (McNemar-Bowker test) yielded no significant differences between the two tools (p = 0.06). Conclusion: The two investigated post-processing algorithms did not differ in terms of prostate cancer detection. The commercially available software tool allows reliable and fast analysis of dynamic contrast-enhanced MRI for the detection of prostate cancer. (orig.)

  4. Complex cystic renal masses: characterization with contrast-enhanced US.

    Science.gov (United States)

    Ascenti, Giorgio; Mazziotti, Silvio; Zimbaro, Giovanni; Settineri, Nicola; Magno, Carlo; Melloni, Darwin; Caruso, Rosario; Scribano, Emanuele

    2007-04-01

    To prospectively compare contrast material-enhanced ultrasonography (US) with computed tomography (CT) in the classification of complex cystic renal masses with the Bosniak system. Ethics committee approval and written informed consent were obtained. Forty patients (17 women, 23 men; age range, 31-77 years) with 44 complex cystic renal masses detected with conventional US were prospectively examined by using second-harmonic US with a second-generation contrast agent and multiphasic helical CT. Thirty-six patients had one lesion, and four patients had two lesions. Surgical resection in nine patients and imaging follow-up in 31 patients were used to determine the outcome. On contrast-enhanced US images, masses were classified as Bosniak category II (n = 18), IIF (ie, lesions were classified as category II and follow-up was needed) (n = 16), III (n = 7), or IV (n = 3) lesions. On CT images, masses were classified as Bosniak category II (n = 24), IIF (n = 10), III (n = 7), or IV (n = 3) lesions. Interobserver agreement was high (kappa = 0.86, P < .001) for classification with US. Complete concordance between the readers was found for classification with CT. Complete concordance between contrast-enhanced US and CT was observed in the differentiation of surgical and nonsurgical complex cysts. Complete concordance among the three readers in the assessment of vascularity with contrast-enhanced US was found. Interobserver agreement in the evaluation of enhancement on CT images was high (kappa = 0.88, P < .001). Concordance between contrast-enhanced US and CT in the evaluation of vascularization was high (kappa = 0.77, P < .001). The study data suggest that contrast-enhanced second-harmonic US is appropriate for renal cyst classification with the Bosniak system.

  5. Automatic Detection of Myocardial Boundaries in MR Cardio Perfusion Images

    NARCIS (Netherlands)

    Spreeuwers, Luuk; Breeuwer, Marcel

    2001-01-01

    Cardiovascular diseases often result in reduced blood perfusion of the myocardium (MC). Recent advances in MR allow fast recordingof contrast enhanced myocardial perfusion scans. For perfusion analysis the myocardial boundaries must be traced. Currently this is done manually. In this paper a method

  6. Measurement of Murine Single-Kidney Glomerular Filtration Rate Using Dynamic Contrast-Enhanced MRI.

    Science.gov (United States)

    Jiang, Kai; Tang, Hui; Mishra, Prasanna K; Macura, Slobodan I; Lerman, Lilach O

    2018-06-01

    To develop and validate a method for measuring murine single-kidney glomerular filtration rate (GFR) using dynamic contrast-enhanced MRI (DCE-MRI). This prospective study was approved by the Institutional Animal Care and Use Committee. A fast longitudinal relaxation time (T 1 ) measurement method was implemented to capture gadolinium dynamics (1 s/scan), and a modified two-compartment model was developed to quantify GFR as well as renal perfusion using 16.4T MRI in mice 2 weeks after unilateral renal artery stenosis (RAS, n = 6) or sham (n = 8) surgeries. This approach was validated by comparing model-derived GFR and perfusion to those obtained by fluorescein isothiocyanante (FITC)-inulin clearance and arterial spin labeling (ASL), respectively, using the Pearson's and Spearman's rank correlations and Bland-Altman analysis. The compartmental model provided a good fitting to measured gadolinium dynamics in both normal and RAS kidneys. The proposed DCE-MRI method offered assessment of single-kidney GFR and perfusion, comparable to the FITC-inulin clearance (Pearson's correlation coefficient r = 0.95 and Spearman's correlation coefficient ρ = 0.94, P < 0.0001, and mean difference -7.0 ± 11.0 μL/min) and ASL (r = 0.92 and ρ = 0.84, P < 0.0001, and mean difference 4.4 ± 66.1 mL/100 g/min) methods. The proposed DCE-MRI method may be useful for reliable noninvasive measurements of single-kidney GFR and perfusion in mice. Magn Reson Med 79:2935-2943, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  7. Dynamic Contrast-Enhanced Ultrasound of Colorectal Liver Metastases as an Imaging Modality for Early Response Prediction to Chemotherapy

    DEFF Research Database (Denmark)

    Mogensen, Marie Benzon; Hansen, Martin Lundsgaard; Henriksen, Birthe Merete

    2017-01-01

    Our aim was to investigate whether dynamic contrast-enhanced ultrasound (DCE-US) can detect early changes in perfusion of colorectal liver metastases after initiation of chemotherapy. Newly diagnosed patients with colorectal cancer with liver metastases were enrolled in this explorative prospective...... study. Patients were treated with capecitabine or 5-fluorouracil-based chemotherapy with or without bevacizumab. DCE-US was performed before therapy (baseline) and again 10 days after initiation of treatment. Change in contrast-enhancement in one liver metastasis (indicator lesion) was measured....... Treatment response was evaluated with a computed tomography (CT) scan after three cycles of treatment and the initially observed DCE-US change of the indicator lesion was related to the observed CT response. Eighteen patients were included. Six did not complete three series of chemotherapy...

  8. Ultrasonographic contrast-enhanced study of sicca syndrome

    International Nuclear Information System (INIS)

    Giuseppetti, Gian Marco; Argalia, Giulio; Salera, Diego; Ranaldi, Roberto; Danieli, Giovanna; Cappelli, Marida

    2005-01-01

    Objective: To assess the ability of US contrast-enhanced time-intensity curves to depict the changes connected with sicca syndrome, a fairly common condition that is often associated with autoimmune disorders such as Sjogren's syndrome or other diseases. Diagnostic criteria are complex and controversial and although no single test can be considered the gold standard, salivary gland scintigraphy and biopsy are reliable diagnostic methods. Materials and methods: Sixty consecutive patients with sicca syndrome, 40 of whom had primary (n = 23) or secondary (n = 17) Sjogren's syndrome and 20 had non-Sjogren's sicca syndrome, selected according to European Community Study Group diagnostic criteria for Sjogren's syndrome and subjected to contrast-enhanced US imaging of the parotids using a second-generation contrast agent with analysis of time-intensity curves at rest and during salivary stimulation, Tc99m salivary gland scintigraphy and labial gland biopsy. Results: In the 40 Sjogren's patients, US enhancement values were significantly lower (P < 0.0001 and P < 0.00003, respectively) than in the 20 non-Sjogren's patients both at rest and during stimulation. In the 23 subjects with the primary syndrome, values during stimulation were significantly lower than in the 17 subjects with the secondary syndrome (P < 0.0006), whereas at rest differences were not significant. Contrast-enhanced US imaging allowed to discriminate Sjogren's from non-Sjogren's sicca patients with 87.5% sensitivity, 85% specificity and 86.7% accuracy and the primary from the secondary syndrome with 78.2% sensitivity, 70.5% specificity and 75% accuracy. Interestingly, in eight patients with the primary syndrome, i.e. those with the more severe gland involvement, enhancement values were lower during stimulation than at rest. Conclusion: Preliminary results indicate that contrast-enhanced US imaging can provide useful information on sicca characterisation and severity

  9. Ultrasonographic contrast-enhanced study of sicca syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Giuseppetti, Gian Marco [Institute of Radiology, University School of Medicine, Umberto I Hospital, Via Conca 1, Ancona (Italy)]. E-mail: gm.giuseppetti@ao-umbertoprimo.marche.it; Argalia, Giulio [Institute of Radiology, University School of Medicine, Umberto I Hospital, Via Conca 1, Ancona (Italy); Salera, Diego [Institute of Radiology, University School of Medicine, Umberto I Hospital, Via Conca 1, Ancona (Italy); Ranaldi, Roberto [Institute of Pathological Anatomy and Histopathology, University School of Medicine, Umberto I Hospital, Ancona (Italy); Danieli, Giovanna [Institute of Internal Medicine, University School of Medicine, Umberto I Hospital, Ancona (Italy); Cappelli, Marida [Institute of Internal Medicine, University School of Medicine, Umberto I Hospital, Ancona (Italy)

    2005-05-01

    Objective: To assess the ability of US contrast-enhanced time-intensity curves to depict the changes connected with sicca syndrome, a fairly common condition that is often associated with autoimmune disorders such as Sjogren's syndrome or other diseases. Diagnostic criteria are complex and controversial and although no single test can be considered the gold standard, salivary gland scintigraphy and biopsy are reliable diagnostic methods. Materials and methods: Sixty consecutive patients with sicca syndrome, 40 of whom had primary (n = 23) or secondary (n = 17) Sjogren's syndrome and 20 had non-Sjogren's sicca syndrome, selected according to European Community Study Group diagnostic criteria for Sjogren's syndrome and subjected to contrast-enhanced US imaging of the parotids using a second-generation contrast agent with analysis of time-intensity curves at rest and during salivary stimulation, Tc99m salivary gland scintigraphy and labial gland biopsy. Results: In the 40 Sjogren's patients, US enhancement values were significantly lower (P < 0.0001 and P < 0.00003, respectively) than in the 20 non-Sjogren's patients both at rest and during stimulation. In the 23 subjects with the primary syndrome, values during stimulation were significantly lower than in the 17 subjects with the secondary syndrome (P < 0.0006), whereas at rest differences were not significant. Contrast-enhanced US imaging allowed to discriminate Sjogren's from non-Sjogren's sicca patients with 87.5% sensitivity, 85% specificity and 86.7% accuracy and the primary from the secondary syndrome with 78.2% sensitivity, 70.5% specificity and 75% accuracy. Interestingly, in eight patients with the primary syndrome, i.e. those with the more severe gland involvement, enhancement values were lower during stimulation than at rest. Conclusion: Preliminary results indicate that contrast-enhanced US imaging can provide useful information on sicca characterisation and

  10. Algorithms for contrast enhancement of electronic portal images

    International Nuclear Information System (INIS)

    Díez, S.; Sánchez, S.

    2015-01-01

    An implementation of two new automatized image processing algorithms for contrast enhancement of portal images is presented as suitable tools which facilitate the setup verification and visualization of patients during radiotherapy treatments. In the first algorithm, called Automatic Segmentation and Histogram Stretching (ASHS), the portal image is automatically segmented in two sub-images delimited by the conformed treatment beam: one image consisting of the imaged patient obtained directly from the radiation treatment field, and the second one is composed of the imaged patient outside it. By segmenting the original image, a histogram stretching can be independently performed and improved in both regions. The second algorithm involves a two-step process. In the first step, a Normalization to Local Mean (NLM), an inverse restoration filter is applied by dividing pixel by pixel a portal image by its blurred version. In the second step, named Lineally Combined Local Histogram Equalization (LCLHE), the contrast of the original image is strongly improved by a Local Contrast Enhancement (LCE) algorithm, revealing the anatomical structures of patients. The output image is lineally combined with a portal image of the patient. Finally the output images of the previous algorithms (NLM and LCLHE) are lineally combined, once again, in order to obtain a contrast enhanced image. These two algorithms have been tested on several portal images with great results. - Highlights: • Two Algorithms are implemented to improve the contrast of Electronic Portal Images. • The multi-leaf and conformed beam are automatically segmented into Portal Images. • Hidden anatomical and bony structures in portal images are revealed. • The task related to the patient setup verification is facilitated by the contrast enhancement then achieved.

  11. Contrast enhancement of the gyri in herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Schumacher, K.A.; Langer, M.; Langer, R.

    1982-01-01

    A case of herpes simplex encephalitis was examined by computer tomography. Both cerebral hemispheres showed contrast enhancement of the gyri. The cause of this is considered. The increased contrast medium accumulation in the affected areas is probably due to the marked vascular proliferation which can be demonstrated anatomically, and to the rapid escape of contrast from the capillaries into the interstitial spaces. The findings of other authors, which differ somewhat, are discussed. (orig.) [de

  12. Color and Contrast Enhancement by Controlled Piecewise Affine Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Jose-Luis Lisani

    2012-10-01

    Full Text Available This paper presents a simple contrast enhancement algorithm based on histogram equalization (HE. The proposed algorithm performs a piecewise affine transform of the intensity levels of a digital image such that the new cumulative distribution function will be approximately uniform (as with HE, but where the stretching of the range is locally controlled to avoid brutal noise enhancement. We call this algorithm Piecewise Affine Equalization (PAE. Several experiments show that, in general, the new algorithm improves HE results.

  13. Sequential contrast-enhanced MR imaging of the penis.

    Science.gov (United States)

    Kaneko, K; De Mouy, E H; Lee, B E

    1994-04-01

    To determine the enhancement patterns of the penis at magnetic resonance (MR) imaging. Sequential contrast material-enhanced MR images of the penis in a flaccid state were obtained in 16 volunteers (12 with normal penile function and four with erectile dysfunction). Subjects with normal erectile function showed gradual and centrifugal enhancement of the corpora cavernosa, while those with erectile dysfunction showed poor enhancement with abnormal progression. Sequential contrast-enhanced MR imaging provides additional morphologic information for the evaluation of erectile dysfunction.

  14. Contrast-enhanced ultrasound for extrahepatic lesions: preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Thorelius, Lars E-mail: lars@thorelius.com

    2004-06-01

    Ultrasound imaging (US) is a convenient, inexpensive and non-invasive investigation. Its use is limited by low sensitivity in the detection of a number of parenchymal lesions, especially those produced by trauma, such as infarctions. Contrast enhancement with SonoVue{sup [reg]} improves the sensitivity of ultrasound in the detection and characterization of focal liver lesions to such an extent, that it may replace computed tomography (CT) and magnetic resonance imaging (MRI). Preliminary experience suggests that SonoVue-enhanced sonography may be useful in the detection of lesions in which blood flow is severely reduced as compared to surrounding parenchyma, such as infarctions, lacerations, hematomas, necrotic tissue and non-vascular cysts, especially in the spleen, kidney and pancreas. This technique can also rule out occlusion of the superior mesenteric, splenic and portal veins, and dilation of the biliary tree. Clinical trials comparing contrast-enhanced sonography with contrast-enhanced computed tomography are warranted to establish the role of this inexpensive and non-invasive technique in the routine work-up of patients with abdominal trauma or presenting with sudden flank pain.

  15. Facial nerve palsy: Evaluation by contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Kinoshita, T.; Ishii, K.; Okitsu, T.; Okudera, T.; Ogawa, T.

    2001-01-01

    AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma. Kinoshita T. et al. (2001)

  16. Facial nerve palsy: Evaluation by contrast-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, T.; Ishii, K.; Okitsu, T.; Okudera, T.; Ogawa, T

    2001-11-01

    AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma. Kinoshita T. et al. (2001)

  17. Contrast enhanced MRI findings of ductal carcinoma in situ

    International Nuclear Information System (INIS)

    Kang, Bong Joo; Cha, Eun Suk; Kim, Hyeon Sook; Suh, Young Jin; Choi, Hyun Joo

    2006-01-01

    The purpose of this study is to describe characteristic contrast enhanced MR mammographic findings of ductal carcinoma in situ (DCIS) and also DCIS with microinvasion. From January 2000 to July 2005, 32 women with 33 lesions affected by DCIS or DCIS with microinvasion underwent contrast enhanced MRI, and they were then retrospectively evaluated. All the patients had previously undergone mammography and ultrasonography. All the findings of mammography, ultrasonography (US), and MRI were analyzed by using an ACR BI-RADS lexicon. All 33 cases were enhanced on the enhanced MR images. A smooth margined homogeneous enhanced mass was seen in the two (2/33) cases, and nonmass enhancement was seen in 31 (31/33) cases. Among the non-mass enhancement, focal enhancement (7/31), ductal enhancement (5/31), segmental enhancement (9/31), and regional enhancement (10/31) were observed. On the kinetic study, a wash-out pattern (10/33), a plateau pattern (20/33), and a persistent pattern (3/33) were demonstrated. No significant differences were noted between the pure and microinvasive DCIS. There is no significant difference between pure and microinvasive DCIS. However, contrast enhanced MR images can demonstrate occult foci, multifocal lesion and the tumor extent of DCIS on mammogram or ultrasonogram

  18. Contrast enhancement pattern in MR imaging of acute cerebral infarction

    International Nuclear Information System (INIS)

    Kim, Jong Deok; Cho, Mee Young; Lee, Chae Guk; Song, Dong Hoon

    1994-01-01

    To present the enhancement pattern of acute cerebral or cerebellar cortical infarctions aged 1-3 days on MR. Contrast-enhanced MR images of 26 patients with acute cerebral or cerebellar ischemic events were retrospectively reviewed. MR was performed within 3 days after ictus. Contrast enhancement in the area of infarction was observed in 61.5% (16/26) on MR. Of these 50% (13/26) showed non-parenchymal enhancement (NPE) representing either vascular or leptomeningeal enhancement, 7.7% (2/26) showed parenchymal enhancement (PE), and 2.8% (1/26) showed both NPE and PE. The earliest enhancement was seen in images obtained 12 hours after the onset of symptoms and appeared as NPE. One patient showed NPE without apparent high signal intensity at the corresponding area on T2-weighted images. In 38.5% (10/26), there was no enhancement. Contrast-enhanced MR imaging may be needed in acute ischemic infarction, because NPE may be seen as the earliest MR finding of acute cortical infraction aged 1-3 days

  19. Visual Contrast Enhancement Algorithm Based on Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Chih-Chung Ting

    2015-07-01

    Full Text Available Image enhancement techniques primarily improve the contrast of an image to lend it a better appearance. One of the popular enhancement methods is histogram equalization (HE because of its simplicity and effectiveness. However, it is rarely applied to consumer electronics products because it can cause excessive contrast enhancement and feature loss problems. These problems make the images processed by HE look unnatural and introduce unwanted artifacts in them. In this study, a visual contrast enhancement algorithm (VCEA based on HE is proposed. VCEA considers the requirements of the human visual perception in order to address the drawbacks of HE. It effectively solves the excessive contrast enhancement problem by adjusting the spaces between two adjacent gray values of the HE histogram. In addition, VCEA reduces the effects of the feature loss problem by using the obtained spaces. Furthermore, VCEA enhances the detailed textures of an image to generate an enhanced image with better visual quality. Experimental results show that images obtained by applying VCEA have higher contrast and are more suited to human visual perception than those processed by HE and other HE-based methods.

  20. Contrast Enhancement Algorithm Based on Gap Adjustment for Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Chung-Cheng Chiu

    2016-06-01

    Full Text Available Image enhancement methods have been widely used to improve the visual effects of images. Owing to its simplicity and effectiveness histogram equalization (HE is one of the methods used for enhancing image contrast. However, HE may result in over-enhancement and feature loss problems that lead to unnatural look and loss of details in the processed images. Researchers have proposed various HE-based methods to solve the over-enhancement problem; however, they have largely ignored the feature loss problem. Therefore, a contrast enhancement algorithm based on gap adjustment for histogram equalization (CegaHE is proposed. It refers to a visual contrast enhancement algorithm based on histogram equalization (VCEA, which generates visually pleasing enhanced images, and improves the enhancement effects of VCEA. CegaHE adjusts the gaps between two gray values based on the adjustment equation, which takes the properties of human visual perception into consideration, to solve the over-enhancement problem. Besides, it also alleviates the feature loss problem and further enhances the textures in the dark regions of the images to improve the quality of the processed images for human visual perception. Experimental results demonstrate that CegaHE is a reliable method for contrast enhancement and that it significantly outperforms VCEA and other methods.

  1. Effects of computed tomography contrast medium factors on contrast enhancement

    International Nuclear Information System (INIS)

    Terasawa, Kazuaki; Hatcho, Atsushi; Okuda, Itsuko

    2011-01-01

    The various nonionic iodinated contrast media used in contrast computed tomography (CT) studies differ in terms of their composition, characteristics, and iodine concentration (mgI/ml), as well as the volume injected (ml). Compared with ionic iodinated contrast media, nonionic iodinated contrast media are low-osmolar agents, with different agents having different osmotic pressures. Using a custom-made phantom incorporating a semipermeable membrane, the osmotic flow rate (hounsfield unit (HU)/s) could easily be measured based on the observed increase in CT numbers, and the relationship between the osmotic pressure and the osmotic flow rate could be obtained (r 2 =0.84). In addition, taking the effects of patient size into consideration, the levels of contrast enhancement in the abdominal aorta (AA) and inferior vena cava (IVC) were compared among four types of CT contrast medium. The results showed differences in contrast enhancement in the IVC during the equilibrium phase depending on the type of contrast medium used. It was found that the factors responsible for the differences observed in enhancement in the IVC were the osmotic flow rate and the volume of the blood flow pathways in the circulatory system. It is therefore considered that the reproducibility of contrast enhancement is likely to be reduced in the examination of parenchymal organs, in which scanning must be performed during the equilibrium phase, even if the amount of iodine injected per unit body weight (mgI/kg) is maintained at a specified level. (author)

  2. Contrast Enhancement Algorithm Based on Gap Adjustment for Histogram Equalization

    Science.gov (United States)

    Chiu, Chung-Cheng; Ting, Chih-Chung

    2016-01-01

    Image enhancement methods have been widely used to improve the visual effects of images. Owing to its simplicity and effectiveness histogram equalization (HE) is one of the methods used for enhancing image contrast. However, HE may result in over-enhancement and feature loss problems that lead to unnatural look and loss of details in the processed images. Researchers have proposed various HE-based methods to solve the over-enhancement problem; however, they have largely ignored the feature loss problem. Therefore, a contrast enhancement algorithm based on gap adjustment for histogram equalization (CegaHE) is proposed. It refers to a visual contrast enhancement algorithm based on histogram equalization (VCEA), which generates visually pleasing enhanced images, and improves the enhancement effects of VCEA. CegaHE adjusts the gaps between two gray values based on the adjustment equation, which takes the properties of human visual perception into consideration, to solve the over-enhancement problem. Besides, it also alleviates the feature loss problem and further enhances the textures in the dark regions of the images to improve the quality of the processed images for human visual perception. Experimental results demonstrate that CegaHE is a reliable method for contrast enhancement and that it significantly outperforms VCEA and other methods. PMID:27338412

  3. Visual Contrast Enhancement Algorithm Based on Histogram Equalization

    Science.gov (United States)

    Ting, Chih-Chung; Wu, Bing-Fei; Chung, Meng-Liang; Chiu, Chung-Cheng; Wu, Ya-Ching

    2015-01-01

    Image enhancement techniques primarily improve the contrast of an image to lend it a better appearance. One of the popular enhancement methods is histogram equalization (HE) because of its simplicity and effectiveness. However, it is rarely applied to consumer electronics products because it can cause excessive contrast enhancement and feature loss problems. These problems make the images processed by HE look unnatural and introduce unwanted artifacts in them. In this study, a visual contrast enhancement algorithm (VCEA) based on HE is proposed. VCEA considers the requirements of the human visual perception in order to address the drawbacks of HE. It effectively solves the excessive contrast enhancement problem by adjusting the spaces between two adjacent gray values of the HE histogram. In addition, VCEA reduces the effects of the feature loss problem by using the obtained spaces. Furthermore, VCEA enhances the detailed textures of an image to generate an enhanced image with better visual quality. Experimental results show that images obtained by applying VCEA have higher contrast and are more suited to human visual perception than those processed by HE and other HE-based methods. PMID:26184219

  4. Cranial CT revisited: do we really need contrast enhancement?

    International Nuclear Information System (INIS)

    Demaerel, P.; Buelens, C.; Wilms, G.; Baert, A.L.

    1998-01-01

    The aim of this study was to define guidelines for intravenous contrast administration in cranial CT, as currently there are no recent guidelines based on a large series of patients. In 1900 consecutive patients (1480 adults and 420 children) pre- and post-contrast scan was analysed in order to assess the contribution of contrast enhancement to the diagnosis. The findings were grouped according to whether abnormalities were seen on the pre- and/or post-contrast scan, or whether no abnormalities were seen at all. Sensitivity, specificity, positive predictive value, negative predictive value and accurracy of a pre-contrast scan were used to determine validity. Intravenous contrast enhancement only contributes to the diagnosis if a suspicious abnormality is seen on the unenhanced scan or in the appropriate clinical setting (33.6 %). In the remaining patients (65.6 %) there is no diagnostic contribution, except for a small number of abnormalities (0.8 %). These are often anatomical variants and have no therapeutic impact. The number of contrast-enhanced cranial CT examinations can significantly be reduced by using four general guidelines for contrast administration resulting in considerable cost savings without affecting the quality of service to the patient. These guidelines are defined by the clinical findings/presentation or by the findings on the unenhanced scan. The number of contrast-related complications will be reduced, which may have medicolegal implications. These guidelines can be applied in any radiology department. (orig.) (orig.)

  5. Contrast enhancement pattern in MR imaging of acute cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Deok; Cho, Mee Young; Lee, Chae Guk; Song, Dong Hoon [Inje University College of Medicine, Pusan (Korea, Republic of)

    1994-08-15

    To present the enhancement pattern of acute cerebral or cerebellar cortical infarctions aged 1-3 days on MR. Contrast-enhanced MR images of 26 patients with acute cerebral or cerebellar ischemic events were retrospectively reviewed. MR was performed within 3 days after ictus. Contrast enhancement in the area of infarction was observed in 61.5% (16/26) on MR. Of these 50% (13/26) showed non-parenchymal enhancement (NPE) representing either vascular or leptomeningeal enhancement, 7.7% (2/26) showed parenchymal enhancement (PE), and 2.8% (1/26) showed both NPE and PE. The earliest enhancement was seen in images obtained 12 hours after the onset of symptoms and appeared as NPE. One patient showed NPE without apparent high signal intensity at the corresponding area on T2-weighted images. In 38.5% (10/26), there was no enhancement. Contrast-enhanced MR imaging may be needed in acute ischemic infarction, because NPE may be seen as the earliest MR finding of acute cortical infraction aged 1-3 days.

  6. Applications of contrast enhanced CT through external jugular access

    International Nuclear Information System (INIS)

    Xu Qiaolan; Zou Wenxing; Chen Meixia; Xie Hongbo

    2005-01-01

    Objective: A retrospective analysis and evaluation for the effects of contrast enhanced computed tomography through external jugular access. Methods: 1250 cases (male 692 and female 558) underwent CT contrast enhanced examination were retrospectively reviewed from May, 2002 to Oct, 2002. The patients aged from 12 to 86 years, averagely 49 years. Contrast agent (Ultravist) was given through an intravenous catheter placed in the cubital vein. Precise injection rates were ensured by a power injector (Medrad MCT310, USA). Excellent enhancement was achieved with this protocol in most of the patients, while external jugular access was established in 96 cases because it was unable to setup a cubital venous access. Results: Good enhancement were acquired when 96 cases of contrast agent injected through external jugular vein. And the external jugular access was setup successfully with a single puncture. Conclusion: It is a common occasion when patient undergoing contrast enhanced CT scan is in poor conditions: debility, cachexia, or with complication of chemotherapy or radiation therapy, which often results in invalidity of cabital venous access, and consequently, making bolus injection impossible. The external jugular vein is a large and central blood vessel, which is easy to setup an access. In our experience, an external jugular access should be recommended as a substitution if the cubital venous access is not available. (authors)

  7. Applications of contrast enhanced CT through external jugular access

    Energy Technology Data Exchange (ETDEWEB)

    Qiaolan, Xu; Wenxing, Zou; Meixia, Chen; Hongbo, Xie [The First Affiliated Hospital of Sun Yat-sen University, Guangzhou (China). Dept. of Radiology

    2005-09-15

    Objective: A retrospective analysis and evaluation for the effects of contrast enhanced computed tomography through external jugular access. Methods: 1250 cases (male 692 and female 558) underwent CT contrast enhanced examination were retrospectively reviewed from May, 2002 to Oct, 2002. The patients aged from 12 to 86 years, averagely 49 years. Contrast agent (Ultravist) was given through an intravenous catheter placed in the cubital vein. Precise injection rates were ensured by a power injector (Medrad MCT310, USA). Excellent enhancement was achieved with this protocol in most of the patients, while external jugular access was established in 96 cases because it was unable to setup a cubital venous access. Results: Good enhancement were acquired when 96 cases of contrast agent injected through external jugular vein. And the external jugular access was setup successfully with a single puncture. Conclusion: It is a common occasion when patient undergoing contrast enhanced CT scan is in poor conditions: debility, cachexia, or with complication of chemotherapy or radiation therapy, which often results in invalidity of cabital venous access, and consequently, making bolus injection impossible. The external jugular vein is a large and central blood vessel, which is easy to setup an access. In our experience, an external jugular access should be recommended as a substitution if the cubital venous access is not available. (authors)

  8. Can quantitative contrast-enhanced ultrasonography predict cervical tumor response to neoadjuvant chemotherapy?

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Chuan; Liu, Long-Zhong; Zheng, Wei [Department of Ultrasound, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060 (China); Xie, Yan-Jun [Department of Gynecology and Obstetrics, Zhongcun Town hospital, 140 Renmin Road, Zhongcun Town, Panyu District, Guangzhou, 511400 (China); Xiong, Yong-Hong; Li, An-Hua [Department of Ultrasound, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060 (China); Pei, Xiao-Qing, E-mail: peixq@sysucc.org.cn [Department of Ultrasound, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060 (China)

    2016-11-15

    Highlights: • We assessed the clinical value of quantitative CEUS for prediction of cervical tumor perfusion response to NACT. • IMAX, RT, and TTP changed significantly after one NACT cycle. • Pre-treatment IMAX positively correlated with the absolute and percentage changes in all cervical tumor IMAX after NACT. • Pre-treatment IMAX may be predictive of NACT perfusion response in cervical tumor. - Abstract: Objective: To evaluate the feasibility of quantitative contrast-enhanced ultrasonography (CEUS) for predicting and assessing cervical tumor response to neoadjuvant chemotherapy (NACT). Methods: Thirty-eight cases with stage IB2 or IIA cervical cancer were studied using CEUS before and after one cycle of NACT. The quantitative CEUS parameters maximum intensity (IMAX), rise time (RT), time to peak (TTP), and mean transit time (MTT) were compared between cervical tumors and myometrium (reference zone) using Sonoliver software. Absolute and relative changes in quantitative CEUS parameters were also compared among complete response, partial response, and non-responsive groups. Correlations between pre-treatment IMAX and changes in quantitative parameters were assessed after one cycle of NACT. Results: There were significant changes in cervical tumor IMAX (P < 0.001), RT (P < 0.05), and TTP (P < 0.05) after one cycle of NACT. According to the Response Evaluation Criteria In Solid Tumors guidelines, the enrollments were divided into complete response, partial response, stable disease and progressive disease groups. There were no significant differences in quantitative CEUS parameters among complete response, partial response, and non-responsive groups (P > 0.05). In the stable disease group (n = 17), cervical tumor IMAX, RT, and TTP decreased significantly after NACT (P < 0.001). The absolute and percentage changes in IMAX were positively correlated with pre-treatment IMAX in all 38 patients (r = 0.576, P < 0.001 and r = 0.429, P < 0.001). Conclusion

  9. Perfusion MRI (dynamic susceptibility contrast imaging) with different measurement approaches for the evaluation of blood flow and blood volume in human gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, H. (Den Sundhedsfaglige Kandidatuddannelse, Aarhus Universitet Bygning 1264, Aarhus (Denmark); University College Nordjylland, Aalborg (Denmark)), Email: hnt@ucn.dk; Steffensen, E. (Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark)); Larsson, E. M. (Aalborg Hospital/Aarhus University Hospital, Department of Radiology, Aalborg (Denmark); Uppsala University Hospital, Department of Radiology, Uppsala (Sweden))

    2012-02-15

    Background. Perfusion magnetic resonance imaging (MRI) is increasingly used in the evaluation of brain tumors. Relative cerebral blood volume (rCBV) is usually obtained by dynamic susceptibility contrast (DSC) MRI using normal appearing white matter as reference region. The emerging perfusion technique arterial spin labelling (ASL) presently provides measurement only of cerebral blood flow (CBF), which has not been widely used in human brain tumor studies. Purpose. To assess if measurement of blood flow is comparable with measurement of blood volume in human biopsy-proven gliomas obtained by DSC-MRI using two different regions for normalization and two different measurement approaches. Material and Methods. Retrospective study of 61 patients with different types of gliomas examined with DSC perfusion MRI. Regions of interest (ROIs) were placed in tumor portions with maximum perfusion on rCBF and rCBV maps, with contralateral normal appearing white matter and cerebellum as reference regions. Larger ROIs were drawn for histogram analyses. The type and grade of the gliomas were obtained by histopathology. Statistical comparison was made between diffuse astrocytomas, anaplastic astrocytomas, and glioblastomas. Results. rCBF and rCBV measurements obtained with the maximum perfusion method were correlated when normalized to white matter (r = 0.60) and to the cerebellum (r = 0.49). Histogram analyses of rCBF and rCBV showed that mean and median values as well as skewness and peak position were correlated (0.61 < r < 0.93), whereas for kurtosis and peak height, the correlation coefficient was about 0.3 when comparing rCBF and rCBV values for the same reference region. Neither rCBF nor rCBV quantification provided a statistically significant difference between the three types of gliomas. However, both rCBF and rCBV tended to increase with tumor grade and to be lower in patients who had undergone resection/treatment. Conclusion. rCBF measurements normalized to white matter

  10. Dynamic Susceptibility Contrast Perfusion Magnetic Resonance Imaging Demonstrates Reduced Periventricular Cerebral Blood Flow in Dogs with Ventriculomegaly

    Directory of Open Access Journals (Sweden)

    Martin J. Schmidt

    2017-08-01

    Full Text Available The nature of ventriculomegaly in dogs is still a matter of debate. Signs of increased intraventricular pressure and atrophy of the cerebral white matter have been found in dogs with ventriculomegaly, which would imply increased intraventricular pressure and, therefore, a pathological condition, i.e., to some extent. Reduced periventricular blood flow was found in people with high elevated intraventricular pressure. The aim of this study was to compare periventricular brain perfusion in dogs with and without ventriculomegaly using perfusion weighted-magnetic-resonance-imaging to clarify as to whether ventriculomegaly might be associated with an increase in intraventricular pressure. Perfusion was measured in 32 Cavalier King Charles spaniels (CKCS with ventriculomegaly, 10 CKCSs were examined as a control group. Cerebral blood flow (CBF was measured using free-hand regions of interest (ROI in five brain regions: periventricular white matter, caudate nucleus, parietal cortex, hippocampus, and thalamus. CBF was significantly lower in the periventricular white matter of the dogs with ventriculomegaly (p = 0.0029 but not in the other ROIs. Reduction of periventricular CBF might imply increase of intraventricular pressure in ventriculomegaly.

  11. Dynamic Contrast-Enhanced Computed Tomography-Derived Blood Volume and Blood Flow Correlate With Patient Outcome in Metastatic Renal Cell Carcinoma

    DEFF Research Database (Denmark)

    Mains, Jill Rachel; Donskov, Frede; Pedersen, Erik Morre

    2017-01-01

    = 7). Using a prototype software program (Advanced Perfusion and Permeability Application, Philips Healthcare, Best, the Netherlands), blood volume (BV), blood flow (BF), and permeability surface area product (PS) were calculated for each tumor at baseline, week 5, and week 10. These parameters......OBJECTIVES: The aim was to explore the potential for using dynamic contrast-enhanced computed tomography as a noninvasive functional imaging biomarker before and during the early treatment of metastatic renal cell carcinoma (mRCC). MATERIALS AND METHODS: Dynamic contrast-enhanced computed...

  12. Regorafenib effects on human colon carcinoma xenografts monitored by dynamic contrast-enhanced computed tomography with immunohistochemical validation.

    Directory of Open Access Journals (Sweden)

    Clemens C Cyran

    Full Text Available To investigate dynamic contrast-enhanced computed tomography for monitoring the effects of regorafenib on experimental colon carcinomas in rats by quantitative assessments of tumor microcirculation parameters with immunohistochemical validation.Colon carcinoma xenografts (HT-29 implanted subcutaneously in female athymic rats (n = 15 were imaged at baseline and after a one-week treatment with regorafenib by dynamic contrast-enhanced computed tomography (128-slice dual-source computed tomography. The therapy group (n = 7 received regorafenib daily (10 mg/kg bodyweight. Quantitative parameters of tumor microcirculation (plasma flow, mL/100 mL/min, endothelial permeability (PS, mL/100 mL/min, and tumor vascularity (plasma volume, % were calculated using a 2-compartment uptake model. Dynamic contrast-enhanced computed tomography parameters were validated with immunohistochemical assessments of tumor microvascular density (CD-31, tumor cell apoptosis (TUNEL, and proliferation (Ki-67.Regorafenib suppressed tumor vascularity (15.7±5.3 to 5.5±3.5%; p<0.05 and tumor perfusion (12.8±2.3 to 8.8±2.9 mL/100 mL/min; p = 0.063. Significantly lower microvascular density was observed in the therapy group (CD-31; 48±10 vs. 113±25, p<0.05. In regorafenib-treated tumors, significantly more apoptotic cells (TUNEL; 11844±2927 vs. 5097±3463, p<0.05 were observed. Dynamic contrast-enhanced computed tomography tumor perfusion and tumor vascularity correlated significantly (p<0.05 with microvascular density (CD-31; r = 0.84 and 0.66 and inversely with apoptosis (TUNEL; r = -0.66 and -0.71.Regorafenib significantly suppressed tumor vascularity (plasma volume quantified by dynamic contrast-enhanced computed tomography in experimental colon carcinomas in rats with good-to-moderate correlations to an immunohistochemical gold standard. Tumor response biomarkers assessed by dynamic contrast-enhanced computed tomography may be a promising future

  13. Comparison of Oral Contrast-Enhanced Transabdominal Ultrasound Imaging With Transverse Contrast-Enhanced Computed Tomography in Preoperative Tumor Staging of Advanced Gastric Carcinoma.

    Science.gov (United States)

    He, Xuemei; Sun, Jing; Huang, Xiaoling; Zeng, Chun; Ge, Yinggang; Zhang, Jun; Wu, Jingxian

    2017-12-01

    This study assessed the diagnostic performance of transabdominal oral contrast-enhanced ultrasound (US) imaging for preoperative tumor staging of advanced gastric carcinoma by comparing it with transverse contrast-enhanced computed tomography (CT). This retrospective study included 42 patients with advanced gastric cancer who underwent laparoscopy, radical surgery, or palliative surgery because of serious complications and had a body mass index of less than 25 kg/m 2 . A cereal-based oral contrast agent was used for transabdominal oral contrast-enhanced US. Retrospective analyses were conducted using preoperative tumor staging data acquired by either transabdominal oral contrast-enhanced US or transverse contrast-enhanced CT. Both contrast-enhanced US and contrast-enhanced CT examinations were reviewed by 2 experienced radiologists independently for preoperative tumor staging according to the seventh edition of the TNM classification. The accuracy, sensitivity, and specificity were calculated by comparing the results of contrast-enhanced US and contrast-enhanced CT with pathologic findings. The overall accuracies of the imaging modalities were compared by the McNemar test. No significant difference was noted in the overall accuracy of transabdominal oral contrast-enhanced US (86% [36 of 42]) and transverse contrast-enhanced CT (83% [35 of 42] P > .999). For stage T2 to T4 gastric cancer, the accuracies of transabdominal oral contrast-enhanced US were 88%, 86%, and 98%, respectively, and those of transverse contrast-enhanced CT were 93%, 83%, and 90%. The overall accuracy of transabdominal oral contrast-enhanced US was comparable with that of transverse contrast-enhanced CT for preoperative tumor staging of advanced gastric cancer. © 2017 by the American Institute of Ultrasound in Medicine.

  14. Evaluation of blood perfusion in liver cirrhosis by dynamic contrast enhanced computed tomography

    DEFF Research Database (Denmark)

    Andersen, Mette L.; Fallentin, Eva; Lauridsen, Carsten Ammitzbøl

    2017-01-01

    sampling and a DCE-CT. Patients were consecutively recruited from Department of Hepatology, Rigshospitalet from Dec 2015 to June 2017. We excluded patients with severely impaired kidney function (eGFR

  15. Contrast-enhanced Spectral Mammography: Technique, Indications, and Clinical Applications.

    Science.gov (United States)

    Bhimani, Chandni; Matta, Danielle; Roth, Robyn G; Liao, Lydia; Tinney, Elizabeth; Brill, Kristin; Germaine, Pauline

    2017-01-01

    Contrast-enhanced spectral mammography (CESM) combines the benefits of full field digital mammography with the concept of tumor angiogenesis. Technique and practical applications of CESM are discussed. An overview of the technique is followed by a demonstration of practical applications of CESM in our practice. We have successfully implemented CESM into our practice as a screening, diagnostic, staging, and treatment response tool. It is important to understand the technique of CESM and how to incorporate it into practice. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  16. Contrast-enhanced Ultrasound for Non-tumor Liver Diseases

    Directory of Open Access Journals (Sweden)

    H Maruyama

    2012-03-01

    Full Text Available Contrast-enhanced ultrasound (CEUS is a simple, safe and reliable technique for the clinical management of patients with various liver diseases. Although the major target of the technique may be focal hepatic lesions, it is also effective for the diagnosis of non-tumor liver diseases, such as grading hepatic fibrosis, characterization of chronic liver diseases and diagnosis of portal vein thrombosis. This review article aimed to overview the recent application of CEUS in the assessment of non-tumor liver diseases. Keywords: Cirrhosis, contrast agent, fibrosis, idiopathic portal hypertension, microbubble, portal vein thrombosis, ultrasound.

  17. Fundamentals of quantitative dynamic contrast-enhanced MR imaging.

    Science.gov (United States)

    Paldino, Michael J; Barboriak, Daniel P

    2009-05-01

    Quantitative analysis of dynamic contrast-enhanced MR imaging (DCE-MR imaging) has the power to provide information regarding physiologic characteristics of the microvasculature and is, therefore, of great potential value to the practice of oncology. In particular, these techniques could have a significant impact on the development of novel anticancer therapies as a promising biomarker of drug activity. Standardization of DCE-MR imaging acquisition and analysis to provide more reproducible measures of tumor vessel physiology is of crucial importance to realize this potential. The purpose of this article is to review the pathophysiologic basis and technical aspects of DCE-MR imaging techniques.

  18. A prolapsed cervical disc with diffuse contrast enhancement on CT

    International Nuclear Information System (INIS)

    Goto, Jun; Shinpo, Tomoyuki; Inoue, Kiyoharu; Shigeno, Taku; Ochiai, Chikayuki

    1985-01-01

    A 48-year-old woman with the C5/6 disc herniation was reported. She had noticed vague pains in the left shoulder a half year earlier. Neurological examination showed left lower cervical radicular pains and incomplete Brown-Sequard syndrome of the same side. The disc herniation was diagnosed by myelography and discography. On the CT examination, surprisingly, the prolapsed disc was homogenously enhanced after the administration of intravenous contrast medium. The vertebral angiography showed increased vascularity behind the C5/6 intervertebral space. At operation, a prolapsed nucleus pulposus with proliferated connective tissue was found and curetted. The etiology of contrast enhancement was discussed. (author)

  19. All-phase MR angiography using independent component analysis of dynamic contrast enhanced MRI time series. φ-MRA

    International Nuclear Information System (INIS)

    Suzuki, Kiyotaka; Matsuzawa, Hitoshi; Watanabe, Masaki; Nakada, Tsutomu; Nakayama, Naoki; Kwee, I.L.

    2003-01-01

    Dynamic contrast enhanced magnetic resonance imaging (dynamic MRI) represents a MRI version of non-diffusible tracer methods, the main clinical use of which is the physiological construction of what is conventionally referred to as perfusion images. The raw data utilized for constructing MRI perfusion images are time series of pixel signal alterations associated with the passage of a gadolinium containing contrast agent. Such time series are highly compatible with independent component analysis (ICA), a novel statistical signal processing technique capable of effectively separating a single mixture of multiple signals into their original independent source signals (blind separation). Accordingly, we applied ICA to dynamic MRI time series. The technique was found to be powerful, allowing for hitherto unobtainable assessment of regional cerebral hemodynamics in vivo. (author)

  20. Fuzzy Logic-Based Histogram Equalization for Image Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    V. Magudeeswaran

    2013-01-01

    Full Text Available Fuzzy logic-based histogram equalization (FHE is proposed for image contrast enhancement. The FHE consists of two stages. First, fuzzy histogram is computed based on fuzzy set theory to handle the inexactness of gray level values in a better way compared to classical crisp histograms. In the second stage, the fuzzy histogram is divided into two subhistograms based on the median value of the original image and then equalizes them independently to preserve image brightness. The qualitative and quantitative analyses of proposed FHE algorithm are evaluated using two well-known parameters like average information contents (AIC and natural image quality evaluator (NIQE index for various images. From the qualitative and quantitative measures, it is interesting to see that this proposed method provides optimum results by giving better contrast enhancement and preserving the local information of the original image. Experimental result shows that the proposed method can effectively and significantly eliminate washed-out appearance and adverse artifacts induced by several existing methods. The proposed method has been tested using several images and gives better visual quality as compared to the conventional methods.

  1. Morphological rational multi-scale algorithm for color contrast enhancement

    Science.gov (United States)

    Peregrina-Barreto, Hayde; Terol-Villalobos, Iván R.

    2010-01-01

    Contrast enhancement main goal consists on improving the image visual appearance but also it is used for providing a transformed image in order to segment it. In mathematical morphology several works have been derived from the framework theory for contrast enhancement proposed by Meyer and Serra. However, when working with images with a wide range of scene brightness, as for example when strong highlights and deep shadows appear in the same image, the proposed morphological methods do not allow the enhancement. In this work, a rational multi-scale method, which uses a class of morphological connected filters called filters by reconstruction, is proposed. Granulometry is used by finding the more accurate scales for filters and with the aim of avoiding the use of other little significant scales. The CIE-u'v'Y' space was used to introduce our results since it takes into account the Weber's Law and by avoiding the creation of new colors it permits to modify the luminance values without affecting the hue. The luminance component ('Y) is enhanced separately using the proposed method, next it is used for enhancing the chromatic components (u', v') by means of the center of gravity law of color mixing.

  2. Characteristics of hypertrophic cardiomyopathy on delayed contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Yan Chaowu; Zhao Shihua; Li Hua; Jiang Shiliang; Lu Minjie; Zhang Yan; Wei Yunqing; Ling Jian; Fang Wei

    2010-01-01

    Objective: To analyze the characteristics of hypertrophic cardiomyopathy (HCM) on delayed contrast-enhanced cardiac magnetic resonance imaging (CMRI). Methods: All patients underwent delayed contrast-enhanced CMRI. The left ventricle was divided into 9 segments to assess the location, extent and function of the hypertrophic segments. The t test was applied for the statistics. Results: Of 154 patients, delayed enhancement of' hypertrophic segment was found in 95 cases and non-delayed enhancement in 59 cases. The thickness and number of hypertrophic segment in patients with delayed enhancement were larger than those with non-delayed enhancement [(24.8±5.5) mm vs (20.4± 3.8) mm, t=3.82, P<0.05; (3.3±1.9) vs (2.4±1.7), t=2.26, P<0.05], and the age was younger [(46.0±15.2) years vs (55.0±11.9) years, t=-3.67, P<0.05]. The diffuse enhancement was found in 62 patients, and confluent enhancement in 33 patients. Confluent enhancement was found in all 14 patients after the alcohol ablation procedure. Conclusion: The age, thickness and number of hypertrophic segments in patients with delayed enhancement are different from those with non-delayed enhancement. (authors)

  3. Evaluation of residual hepatocellular carcinoma after transcatheter arterial chemoembolization: Comparison between contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography

    International Nuclear Information System (INIS)

    Kim, Seung Hoon; Lim, Hyo Keun; Lee, Won Jae

    2001-01-01

    To evaluate the effectiveness of contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography (PDUS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinomas (HCCs). The follow-up contrast-enhanced helical CT and contrast-enhanced PDUS were performed for twenty-nine nodular HCCs from twelve patients previously treated with TACE. We defined the residual HCCs as intratumoral enhancing area on contrast-enhanced helical CT and color signal on contrast-enhanced PDUS. The interval between two examinations was less than 2 weeks (mean, 9 days). Two radiologists evaluated two examinations by consensus, and the results of these two examination were compared with the findings of other examinations including CT, angiography, and/or pathology to calculate the sensitivity, specificity and accuracy of two examinations. Of the 29 HCCs, 20 had residual HCCs whereas no residual HCCs in 9 HCCs on pathologic examination and/or follow-up radiologic study. The sensitivity, sensitivity and accuracy of contrast-enhanced helical CT were 65 (13/20), 89 (8/9), and 72% (21/29) while those of contrast-enhanced PDUS were 100 (20/20), 89 (8/9) and 97% (28/29), respectively. A microbubble contrast-enhanced PDUS was more effective in the detection of residual tumor in HCCs following TACE than contrast-enhanced helical CT.

  4. The Role of Dynamic Contrast-Enhanced MRI in a Child with Sport-Induced Avascular Necrosis of the Scaphoid: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Baris Beytullah Koc

    2016-01-01

    Full Text Available Avascular necrosis (AVN of the scaphoid in children is very rare and there is currently no consensus when conservative or operative treatment is indicated. A 10-year-old boy, practicing karate, presented with acute pain in his left wrist after falling on the outstretched hand. Imaging showed a scaphoid waist fracture with signs of an ongoing AVN. The diagnosis of AVN was confirmed with signal loss of the scaphoid on MRI T1. A dynamic contrast-enhanced MRI was performed for further assessment of the proximal pole vascularity and treatment planning. As dynamic contrast-enhanced MRI showed fair perfusion of the proximal pole, an adequate healing potential with conservative treatment was estimated. We achieved union and good function with cast immobilization for fourteen weeks. This case study showed dynamic contrast-enhanced MRI to be a valuable tool in assessing whether conservative or operative treatment is indicated to achieve union and good functional outcome.

  5. Diagnostic value of contrast-enhanced ultrasonography in the characterization of ovarian tumors().

    Science.gov (United States)

    Sconfienza, L M; Perrone, N; Delnevo, A; Lacelli, F; Murolo, C; Gandolfo, N; Serafini, G

    2010-03-01

    Vascularity influences the characteristics of gynecologic tumors observed with direct imaging techniques that reveal the macrovascular component of these lesions (color and power Doppler) and with indirect imaging involving the administration of contrast agents to examine the microcirculation and interstitial perfusion (contrast-enhanced computed tomography [CT] and magnetic resonance [MR] imaging). The purpose of this study was to determine whether contrast-enhanced ultrasonography (CEUS) of ovarian lesions provides useful information that cannot be obtained with conventional US. We used CEUS to assess 72 nonspecific adnexal lesions in 61 patients. CEUS was performed with a 4.8-ml bolus of a second-generation ultrasonographic contrast agent and dedicated imaging algorithms. For each lesion, B-mode morphology, CEUS morphology, and time/intensity curves were evaluated. In 8/61 cases (13.1%) CEUS offered no additional morphovascular information. In 38/61 cases (62.3%), it provided additional information that did not modify the management of the lesion, and in 15/61 cases (24.6%) it gave additional information that modified the management of the lesion. Malignant lesions were characterized by significantly shorter times to peak enhancement (11.9 ± 3.1 s vs 19.8 ± 4.0 s p < 0.01) and significantly higher peak intensity (24.7 ± 4.2 dB vs 17.8 ± 3.3 dB p < 0.01) compared with benign lesions. CEUS improves diagnostic confidence in the characterization of liquid-corpuscular lesions where conventional US is inconclusive. CEUS can be proposed as a valid alternative to CT and MR. However, information obtained by CEUS influences the therapy in a limited percentage of cases (24.6%).

  6. Measurement of choroid plexus perfusion using dynamic susceptibility MR imaging: capillary permeability and age-related changes

    Energy Technology Data Exchange (ETDEWEB)

    Bouzerar, Roger; Chaarani, Bader; Baledent, Olivier [University Hospital, Image Processing Department, Amiens (France); Gondry-Jouet, Catherine [University Hospital, Radiology Department, Amiens (France); Zmudka, Jadwiga [University Hospital, Geriatric Unit, Amiens (France)

    2013-12-15

    The cerebrospinal fluid (CSF) plays a major role in the physiology of the central nervous system. The continuous turnover of CSF is mainly attributed to the highly vascularized choroid plexus (CP) located in the cerebral ventricles which represent a complex interface between blood and CSF. We propose a method for evaluating CP functionality in vivo using perfusion MR imaging and establish the age-related changes of associated parameters. Fifteen patients with small intracranial tumors were retrospectively studied. MR Imaging was performed on a 3T MR Scanner. Gradient-echo echo planar images were acquired after bolus injection of gadolinium-based contrast agent (CA). The software developed used the combined T1- and T2-effects. The decomposition of the relaxivity signals enables the calculation of the CP capillary permeability (K{sub 2}). The relative cerebral blood volume (rCBV), mean transit time (MTT), and signal slope decrease (SSD) were also calculated. The mean permeability K{sub 2} of the extracted CP was 0.033+/-0.18 s{sup -1}. K{sub 2} and SSD significantly decreased with subject's age whereas MTT significantly increased with subject's age. No significant correlation was found for age-related changes in rCBV and rCBF. The decrease in CP permeability is in line with the age-related changes in CSF secretion observed in animals. The MTT increase indicates significant structural changes corroborated by microscopy studies in animals or humans. Overall, DSC MR-perfusion enables an in vivo evaluation of the hemodynamic state of CP. Clinical applications such as neurodegenerative diseases could be considered thanks to specific functional studies of CP. (orig.)

  7. Contrast-enhanced ultrasound features of histologically proven focal nodular hyperplasia: diagnostic performance compared with contrast-enhanced CT

    International Nuclear Information System (INIS)

    Wang, Wei; Chen, Li-Da; Liu, Guang-Jian; Xu, Zuo-Feng; Xie, Xiao-Yan; Wang, Yan; Zhou, Lu-Yao; Lu, Ming-De; Shen, Shun-Li

    2013-01-01

    To investigate and compare contrast-enhanced ultrasound (CEUS) in the characterisation of histologically proven focal nodular hyperplasia (FNH) with contrast-enhanced computed tomography (CECT). CEUS was performed in 85 patients with 85 histologically proven FNHs. Enhancement, centrifugal filling, spoke-wheel arteries, feeding artery and central scarring were reviewed and correlated with lesion size or liver background. Independent factors for predicting FNH from other focal liver lesions (FLLs) were evaluated. Forty-seven FLLs with CECT were randomly selected for comparison of diagnostic performance with CEUS. Centrifugal filling was more common (P = 0.002) and the significant predictor (P = 0.003) in FNHs ≤3 cm. Lesion size or liver background has no significant influence on the detection rate of the spoke-wheel arteries and feeding artery (P > 0.05). Central scarring was found in 42.6 % of FNHs ≥3 cm (P = 0.000). The area under the ROC curve, sensitivity and specificity showed no significant differences between CEUS and CECT (P > 0.05), except that the sensitivity of CEUS was better for reader 1 (P = 0.041). CEUS is valuable in characterising centrifugal filling signs or spoke wheels in small FNHs and should be employed as the first-line imaging technique for diagnosis of FNH. (orig.)

  8. VEGFR-2 expression in HCC, dysplastic and regenerative liver nodules, and correlation with pre-biopsy Dynamic Contrast Enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Thaiss, W.M., E-mail: wolfgang.thaiss@med.uni-tuebingen.de [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Hoppe-Seyler-Str. 3, D-72076 Tuebingen (Germany); Kaufmann, S., E-mail: sascha.kaufmann@med.uni-tuebingen.de [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Hoppe-Seyler-Str. 3, D-72076 Tuebingen (Germany); Kloth, C., E-mail: christopher.kloth@med.uni-tuebingen.de [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Hoppe-Seyler-Str. 3, D-72076 Tuebingen (Germany); Nikolaou, K., E-mail: konstantin.nikolaou@med.uni-tuebingen.de [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Hoppe-Seyler-Str. 3, D-72076 Tuebingen (Germany); Bösmüller, H., E-mail: hans.boesmueller@med.uni-tuebingen.de [Eberhard Karls University, Department of Pathology, Liebermeisterstraße 8, D-72076 Tuebingen (Germany); Horger, M., E-mail: Marius.Horger@med.uni-tuebingen.de [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Hoppe-Seyler-Str. 3, D-72076 Tuebingen (Germany)

    2016-11-15

    Highlights: • VEGFR-2-expression levels vary between HCC, dysplastic and regenerative liver nodules. • Perfusion parameters vary between these groups in blood flow, blood volume and HPI. • Strong correlations were observed between perfusion parameters and VEGFR-2-expression. • The results might influence diagnosis and therapy of anti-vascular therapeutic regimes. - Abstract: Purpose: To evaluate whether VEGFR-2-expression in hepatocellular carcinoma (HCC), dysplastic (DLN) and regenerative liver nodules (RLN) correlates with pre-histology, in vivo Dynamic Contrast Enhanced-Computed Tomography (DCE-CT) data as VEGFR-2-expression affects prognosis and therapeutic options. Materials and methods: 34 patients (63.6 ± 8.9 years, 7 females) underwent liver biopsy or surgery due to suspected HCC or dysplastic nodules after DCE-CT between 2009 and 2015 with no previous chemo- or interventional therapy. Immunohistochemistry staining for VEGFR-2 was performed using Immunoreactive-Remmele-Stegner-Score (IRS) for quantification. A 128-row CT-scanner was used for DCE-CT with assessment of perfusion parameters blood flow (BF), blood volume (BV), arterial liver perfusion (ALP), portal venous perfusion (PVP), and hepatic perfusion index (HPI). Results: Histology confirmed HCC (n = 10), DLN (n = 7) and RLN (n = 34). Mean IRS for VEGFR-2 in HCCs was 9.1 ± 3.0, 7.3 ± 1.6 for DLN and 5.2 ± 2.8 for RLN (p = 0.0004 for HCC vs. RLN). Perfusion values varied significantly between all three groups for BF and HPI (p < 0.001 and p < 0.0001) and for BV in HCC vs. RLN (p < 0.0001) and DLN vs. RLN (p = 0.0019). Strong correlations between VEGFR-2-IRS and perfusion parameters were observed for BF in HCC (r = 0.88, p < 0.01) and HPI in HCC and DLN (r = 0.85, p < 0.04; r = 0.9, p < 0.01). Conclusion: Immunostaining revealed different VEGFR-2-expression levels in HCC, dysplastic and regenerative liver nodules. Perfusion markers blood flow, blood volume and hepatic perfusion index

  9. Value of contrast-enhanced ultrasound in rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Zordo, Tobias de; Mlekusch, Sabine P.; Feuchtner, Gudrun M. [Department of Radiology II, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria); Mur, Erich [Department of Internal Medicine, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria); Schirmer, Michael [Department of Internal Medicine, Hospital of the Elisabethines Klagenfurt, Voelkermarkter Strasse 15-19, 9020 Klagenfurt (Austria); Klauser, Andrea S. [Department of Radiology II, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck (Austria)], E-mail: andrea.klauser@i-med.ac.at

    2007-11-15

    The purpose of this review is to describe the spectrum of sonographic findings in rheumatic diseases with respect to the diagnostic potential using US contrast media which prove activity or inactivity in synovial tissue where new treatment regimes target. Synovial activity can be found in non-erosive and erosive forms of primary and secondary osteoarthritis, and in inflammatory forms of joint diseases like rheumatoid arthritis and peripheral manifestations of spondyloarthritis including, ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis and enteropathic arthritis. It can also be present in metabolic and endocrine forms of arthritis, in connective tissue arthropathies like systemic lupus erythematosus or scleroderma and in infectious arthritis. Ultrasound should be used as first-line imaging modality in suspected early cases of RA and other forms of arthritis, whereas contrast-enhanced ultrasound (CEUS) can further enable for sensitive assessment of vascularity which correlates with disease activity.

  10. Image contrast enhancement based on a local standard deviation model

    International Nuclear Information System (INIS)

    Chang, Dah-Chung; Wu, Wen-Rong

    1996-01-01

    The adaptive contrast enhancement (ACE) algorithm is a widely used image enhancement method, which needs a contrast gain to adjust high frequency components of an image. In the literature, the gain is usually inversely proportional to the local standard deviation (LSD) or is a constant. But these cause two problems in practical applications, i.e., noise overenhancement and ringing artifact. In this paper a new gain is developed based on Hunt's Gaussian image model to prevent the two defects. The new gain is a nonlinear function of LSD and has the desired characteristic emphasizing the LSD regions in which details are concentrated. We have applied the new ACE algorithm to chest x-ray images and the simulations show the effectiveness of the proposed algorithm

  11. CT angiography. Abdominal CT using intravenous aortography for contrast enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, J; Nakauma, Y; Egawa, J; Kawamura, M [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

    1980-04-01

    To obtain imaging effects close to those of abdominal aortography and investigate a technique with little invasion to patients, intravenous aortography was applied to contrast enhancement (CE) in abdominal CT, and its usefulness was discussed. Intravenous aortography could clearly visualize lesions with rich neovascularity such as hepatocellular carcinoma and renal cell carcinoma. Differing from a drip infusion method, this method has complexities in its technique that contrast medium is injected at once, blood circulation time which is represented by the time between the injection and the time when the patients feel bitterness (10 - 12 seconds) must be measured before CE, and scanning begins 2 seconds before the patients feel bitterness. However, the invasion to patients due to this method is slight, and the capacity of this method to visualize neovascularity is superior to CE by a drip infusion method. Therefore, qualitative diagnosis by CT will be improved by using this method together with a drip infusion method.

  12. Value of contrast-enhanced ultrasound in rheumatoid arthritis

    International Nuclear Information System (INIS)

    Zordo, Tobias de; Mlekusch, Sabine P.; Feuchtner, Gudrun M.; Mur, Erich; Schirmer, Michael; Klauser, Andrea S.

    2007-01-01

    The purpose of this review is to describe the spectrum of sonographic findings in rheumatic diseases with respect to the diagnostic potential using US contrast media which prove activity or inactivity in synovial tissue where new treatment regimes target. Synovial activity can be found in non-erosive and erosive forms of primary and secondary osteoarthritis, and in inflammatory forms of joint diseases like rheumatoid arthritis and peripheral manifestations of spondyloarthritis including, ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis and enteropathic arthritis. It can also be present in metabolic and endocrine forms of arthritis, in connective tissue arthropathies like systemic lupus erythematosus or scleroderma and in infectious arthritis. Ultrasound should be used as first-line imaging modality in suspected early cases of RA and other forms of arthritis, whereas contrast-enhanced ultrasound (CEUS) can further enable for sensitive assessment of vascularity which correlates with disease activity

  13. Magnetic iron oxide for contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Fahlvik, A.K.

    1991-05-01

    The main objective of this experimental work has been to study the biological fate and the contrast enhancing potential of a model preparation of magnetic iron oxide (MSM) after intravenous injection to rodents. This was achieved by: Studying in vitro contrast efficacy of various magnetic iron oxide preparations by relaxation analysis. Studying in vivo contrast efficacy of MSM by relaxation analysis and NMR imaging. Studying the biodistribution and bioelimination of MSM in independent experiments using relaxation analysis, radioactivity studies and histological techniques. Studying interactions of MSM with target cells and target organelles using ex vivo techniques. Based on the presented experimental study, the MSM model preparation of magnetic iron oxide seems to fulfill basic requirements of NMR contrast agents: efficient proton relaxation, specific in vivo distribution, and biological tolerance. 177 refs., 5 figs., 2 tabs

  14. Research on Wavelet-Based Algorithm for Image Contrast Enhancement

    Institute of Scientific and Technical Information of China (English)

    Wu Ying-qian; Du Pei-jun; Shi Peng-fei

    2004-01-01

    A novel wavelet-based algorithm for image enhancement is proposed in the paper. On the basis of multiscale analysis, the proposed algorithm solves efficiently the problem of noise over-enhancement, which commonly occurs in the traditional methods for contrast enhancement. The decomposed coefficients at same scales are processed by a nonlinear method, and the coefficients at different scales are enhanced in different degree. During the procedure, the method takes full advantage of the properties of Human visual system so as to achieve better performance. The simulations demonstrate that these characters of the proposed approach enable it to fully enhance the content in images, to efficiently alleviate the enhancement of noise and to achieve much better enhancement effect than the traditional approaches.

  15. Contrast-enhanced breast MRI: factors affecting sensitivity and specificity

    Energy Technology Data Exchange (ETDEWEB)

    Piccoli, C.W. [Department of Radiology, Jefferson Medical College, Thomas Jefferson University Hospital, 132 South 10th Street, 7th floor, Philadelphia, PA 19107-5244 (United States)

    1997-12-31

    Contrast-enhanced MRI (CE-MRI) of the breast has been investigated for over 10 years. The reports of sensitivity for cancer detection have generally been greater than 90 %. However, estimates of specificity have varied greatly. Differing results are due to differences in study populations, technical methods and criteria for interpretation. Early and marked signal rise, detected using dynamic imaging technique following contrast administration, is the MRI hallmark of cancer. However, some malignant lesions may enhance slowly or minimally, and a variety of benign lesions may enhance rapidly with marked signal intensity. High resolution techniques generally requiring longer acquisition times are more likely to depict the slowly enhancing malignancies at the cost of a decrease in specificity due to lack of temporal resolution. This disadvantage may be offset by the improved visualization of lesion morphology with high resolution images. This report reviews the methods and results of the leading investigators of breast MRI. (orig.) With 3 figs., 70 refs.

  16. Contrast-enhanced breast MRI: factors affecting sensitivity and specificity

    International Nuclear Information System (INIS)

    Piccoli, C.W.

    1997-01-01

    Contrast-enhanced MRI (CE-MRI) of the breast has been investigated for over 10 years. The reports of sensitivity for cancer detection have generally been greater than 90 %. However, estimates of specificity have varied greatly. Differing results are due to differences in study populations, technical methods and criteria for interpretation. Early and marked signal rise, detected using dynamic imaging technique following contrast administration, is the MRI hallmark of cancer. However, some malignant lesions may enhance slowly or minimally, and a variety of benign lesions may enhance rapidly with marked signal intensity. High resolution techniques generally requiring longer acquisition times are more likely to depict the slowly enhancing malignancies at the cost of a decrease in specificity due to lack of temporal resolution. This disadvantage may be offset by the improved visualization of lesion morphology with high resolution images. This report reviews the methods and results of the leading investigators of breast MRI. (orig.)

  17. Contrast enhancement of cranial lesions in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lewander, R; Bergstroem, M; Bergvall, U [Kungliga Karolinska Mediko-Kirurgiska Inst., Stockholm (Sweden)

    1978-01-01

    The time course of enhancement in apparently normal brain tissue, edema and focal lesions during 30 to 60 min after intravenous injection of vascular contrast medium was evaluated in a series of 41 pateints with differnt intracranial lesions. The attenuation of apparently normal unenhanced brain tissue varied with the level of the scan, mainly an effect of beam hardening. Different types of enhancement response are discussed in terms of a 3-compartment model. The differential diagnostic potential of contrast enhancement in the early phase needs further evaluation using instruments with short scanning time, while the late phase of enhancement must be recorded with the use of a reliable head fixation to provide reproducibility of repeat measurements.

  18. Quantitative Assessment of Hepatic Fibrosis by Contrast-enhanced Ultrasonography

    Institute of Scientific and Technical Information of China (English)

    Ming-bo Zhang; En-ze Qu; Ji-Bin Liu; Jin-rui Wang

    2011-01-01

    Objective To explore the contrast-enhanced ultrasonographic features for quantitative assessment of hepatic fibrosis.Methods 86 patients with chronic viral hepatitis B were enrolled in this study from March 2007 to August 2009.The patients were classified into 5 groups (S0-S4) according to fibrosis stage evaluated with ultrasound guided liver biopsy.New contrast-enhanced ultrasonography (CEUS) features including area under the time-intensity curve (TIC) of portal venous phase/hepatic arterial phase (Qp/Qa) and intensity of portal venons phase/hepatic arterial phase (Ip/Ia) were used to detect the blood supply ratio (portal vein/hepatic artery) in each group.Arrival time of portal vein trunk (Tp) and decreasing rate of TIC (β) were also analyzed.Results Qp/Qa and Ip/Ia decreased from So to S4,while Tp and β increased These 4 features were significantly correlated with the degree of fibrosis (P<0.001) and were significantly different among the five groups (P<0.001).Sensitivity and specificity of Ip/Ia were 80% and 86% for groups ≥S1,75% and 86% for groups ≥ S2,71% and 84% for groups ≥ S3,and 76% and 80% for group S4,respectively.Sensitivity and specificity of Qp/Qa were 70% and 88% for groups ≥ S1,80% and 76% for groups ≥ S2,74% and 70% for groups ≥ S3,and 81% and 95% for group S4,respectively.Conclusion Ip/Ia and Qp/Qa could be adopted as reliable,non-invasive features for quantitative assessment of hepatic fibrosis.

  19. Quantitative contrast-enhanced mammography for contrast medium kinetics studies

    Science.gov (United States)

    Arvanitis, C. D.; Speller, R.

    2009-10-01

    Quantitative contrast-enhanced mammography, based on a dual-energy approach, aims to extract quantitative and temporal information of the tumour enhancement after administration of iodinated vascular contrast media. Simulations using analytical expressions and optimization of critical parameters essential for the development of quantitative contrast-enhanced mammography are presented. The procedure has been experimentally evaluated using a tissue-equivalent phantom and an amorphous silicon active matrix flat panel imager. The x-ray beams were produced by a tungsten target tube and spectrally shaped using readily available materials. Measurement of iodine projected thickness in mg cm-2 has been performed. The effect of beam hardening does not introduce nonlinearities in the measurement of iodine projected thickness for values of thicknesses found in clinical investigations. However, scattered radiation introduces significant deviations from slope equal to unity when compared with the actual iodine projected thickness. Scatter correction before the analysis of the dual-energy images provides accurate iodine projected thickness measurements. At 10% of the exposure used in clinical mammography, signal-to-noise ratios in excess of 5 were achieved for iodine projected thicknesses less than 3 mg cm-2 within a 4 cm thick phantom. For the extraction of temporal information, a limited number of low-dose images were used with the phantom incorporating a flow of iodinated contrast medium. The results suggest that spatial and temporal information of iodinated contrast media can be used to indirectly measure the tumour microvessel density and determine its uptake and washout from breast tumours. The proposed method can significantly improve tumour detection in dense breasts. Its application to perform in situ x-ray biopsy and assessment of the oncolytic effect of anticancer agents is foreseeable.

  20. Adaptive radiotherapy based on contrast enhanced cone beam CT imaging

    International Nuclear Information System (INIS)

    Soevik, Aaste; Skogmo, Hege K.; Roedal, Jan; Lervaag, Christoffer; Eilertsen, Karsten; Malinen, Eirik

    2010-01-01

    Cone beam CT (CBCT) imaging has become an integral part of radiation therapy, with images typically used for offline or online patient setup corrections based on bony anatomy co-registration. Ideally, the co-registration should be based on tumor localization. However, soft tissue contrast in CBCT images may be limited. In the present work, contrast enhanced CBCT (CECBCT) images were used for tumor visualization and treatment adaptation. Material and methods. A spontaneous canine maxillary tumor was subjected to repeated cone beam CT imaging during fractionated radiotherapy (10 fractions in total). At five of the treatment fractions, CECBCT images, employing an iodinated contrast agent, were acquired, as well as pre-contrast CBCT images. The tumor was clearly visible in post-contrast minus pre-contrast subtraction images, and these contrast images were used to delineate gross tumor volumes. IMRT dose plans were subsequently generated. Four different strategies were explored: 1) fully adapted planning based on each CECBCT image series, 2) planning based on images acquired at the first treatment fraction and patient repositioning following bony anatomy co-registration, 3) as for 2), but with patient repositioning based on co-registering contrast images, and 4) a strategy with no patient repositioning or treatment adaptation. The equivalent uniform dose (EUD) and tumor control probability (TCP) calculations to estimate treatment outcome for each strategy. Results. Similar translation vectors were found when bony anatomy and contrast enhancement co-registration were compared. Strategy 1 gave EUDs closest to the prescription dose and the highest TCP. Strategies 2 and 3 gave EUDs and TCPs close to that of strategy 1, with strategy 3 being slightly better than strategy 2. Even greater benefits from strategies 1 and 3 are expected with increasing tumor movement or deformation during treatment. The non-adaptive strategy 4 was clearly inferior to all three adaptive strategies

  1. Perfusion abnormalities in congenital and neoplastic pulmonary disease: comparison of MR perfusion and multislice CT imaging

    International Nuclear Information System (INIS)

    Boll, Daniel T.; Lewin, Jonathan S.; Young, Philip; Gilkeson, Robert C.; Siwik, Ernest S.

    2005-01-01

    The aim of this work was to assess magnetic resonance (MR) perfusion patterns of chronic, nonembolic pulmonary diseases of congenital and neoplastic origin and to compare the findings with results obtained with pulmonary, contrast-enhanced multislice computed tomography (CT) imaging to prove that congenital and neoplastic pulmonary conditions require MR imaging over the pulmonary perfusion cycle to successfully and directly detect changes in lung perfusion patterns. Twenty-five patients underwent concurrent CT and MR evaluation of chronic pulmonary diseases of congenital (n=15) or neoplastic (n=10) origin. Analysis of MR perfusion and contrast-enhanced CT datasets was realized by defining pulmonary and vascular regions of interest in corresponding positions. MR perfusion calculated time-to-peak enhancement, maximal enhancement and the area under the perfusion curve. CT datasets provided pulmonary signal-to-noise ratio measurements. Vessel centerlines of bronchial arteries were determined. Underlying perfusion type, such as pulmonary arterial or systemic arterial supply, as well as regions with significant variations in perfusion were determined statistically. Analysis of the pulmonary perfusion pattern detected pulmonary arterial supply in 19 patients; six patients showed systemic arterial supply. In pulmonary arterial perfusion, MR and multislice CT imaging consistently detected the perfusion type and regions with altered perfusion patterns. In bronchial arterial supply, MR perfusion and CT imaging showed significant perfusion differences. Patients with bronchial arterial supply had bronchial arteries ranging from 2.0 to 3.6 mm compared with submillimeter diameters in pulmonary arterial perfusion. Dynamic MR imaging of congenital and neoplastic pulmonary conditions allowed characterization of the pulmonary perfusion type. CT imaging suggested the presence of systemic arterial perfusion by visualizing hypertrophied bronchial arteries. (orig.)

  2. IDH mutant and 1p/19q co-deleted oligodendrogliomas: tumor grade stratification using diffusion-, susceptibility-, and perfusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yu; Xing, Zhen; She, Dejun; Yang, Xiefeng; Zheng, Yingyan; Xiao, Zebin; Cao, Dairong [First Affiliated Hospital of Fujian Medical University, Department of Radiology, Fuzhou, Fujian (China); Wang, Xingfu [First Affiliated Hospital of Fujian Medical University, Department of Pathology, Fuzhou (China)

    2017-06-15

    Currently, isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion are proven diagnostic biomarkers for both grade II and III oligodendrogliomas (ODs). Non-invasive diffusion-weighted imaging (DWI), susceptibility-weighted imaging (SWI), and dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) are widely used to provide physiological information (cellularity, hemorrhage, calcifications, and angiogenesis) of neoplastic histology and tumor grade. However, it is unclear whether DWI, SWI, and DSC-PWI are able to stratify grades of IDH-mutant and 1p/19q co-deleted ODs. We retrospectively reviewed the conventional MRI (cMRI), DWI, SWI, and DSC-PWI obtained on 33 patients with IDH-mutated and 1p/19q co-deleted ODs. Features of cMRI, normalized ADC (nADC), intratumoral susceptibility signals (ITSSs), normalized maxim CBV (nCBV), and normalized maximum CBF (nCBF) were compared between low-grade ODs (LGOs) and high-grade ODs (HGOs). Receiver operating characteristic curve and logistic regression were applied to determine diagnostic performances. HGOs tended to present with prominent edema and enhancement. nADC, ITSSs, nCBV, and nCBF were significantly different between groups (all P < 0.05). The combination of SWI and DSC-PWI for grading resulted in sensitivity and specificity of 100.00 and 93.33%, respectively. IDH-mutant and 1p/19q co-deleted ODs can be stratified by grades using cMRI and advanced magnetic resonance imaging techniques including DWI, SWI, and DSC-PWI. Combined ITSSs with nCBV appear to be a promising option for grading molecularly defined ODs in clinical practice. (orig.)

  3. Automated Processing of Dynamic Contrast-Enhanced MRI: Correlation of Advanced Pharmacokinetic Metrics with Tumor Grade in Pediatric Brain Tumors.

    Science.gov (United States)

    Vajapeyam, S; Stamoulis, C; Ricci, K; Kieran, M; Poussaint, T Young

    2017-01-01

    Pharmacokinetic parameters from dynamic contrast-enhanced MR imaging have proved useful for differentiating brain tumor grades in adults. In this study, we retrospectively reviewed dynamic contrast-enhanced perfusion data from children with newly diagnosed brain tumors and analyzed the pharmacokinetic parameters correlating with tumor grade. Dynamic contrast-enhanced MR imaging data from 38 patients were analyzed by using commercially available software. Subjects were categorized into 2 groups based on pathologic analyses consisting of low-grade (World Health Organization I and II) and high-grade (World Health Organization III and IV) tumors. Pharmacokinetic parameters were compared between the 2 groups by using linear regression models. For parameters that were statistically distinct between the 2 groups, sensitivity and specificity were also estimated. Eighteen tumors were classified as low-grade, and 20, as high-grade. Transfer constant from the blood plasma into the extracellular extravascular space (K trans ), rate constant from extracellular extravascular space back into blood plasma (K ep ), and extracellular extravascular volume fraction (V e ) were all significantly correlated with tumor grade; high-grade tumors showed higher K trans , higher K ep , and lower V e . Although all 3 parameters had high specificity (range, 82%-100%), K ep had the highest specificity for both grades. Optimal sensitivity was achieved for V e , with a combined sensitivity of 76% (compared with 71% for K trans and K ep ). Pharmacokinetic parameters derived from dynamic contrast-enhanced MR imaging can effectively discriminate low- and high-grade pediatric brain tumors. © 2017 by American Journal of Neuroradiology.

  4. Myocardial enhancement pattern in patients with acute myocardial infarction on two-phase contrast-enhanced Ecg-gated multidetector-row computed tomography

    International Nuclear Information System (INIS)

    Ko, S.M.; Seo, J.B.; Hong, M.K.; Do, K.H.; Lee, S.H.; Lee, J.S.; Song, J.W.; Park, S.J.; Park, S.W.; Lim, T.H.

    2006-01-01

    Aim: To evaluate the myocardial enhancement pattern of the left ventricle on two-phase contrast-enhanced electrocardiogram (ECG)-gated multidetector computed tomography (MDCT) images in patients with acute myocardial infarction (AMI). METHODS: Two-phase contrast-enhanced ECG-gated MDCT examinations were performed in 16 patients with AMI. The presence, location and pattern of myocardial enhancement were evaluated. MDCT findings were compared with the catheter angiographic results. RESULTS: Subendocardial (n=9) or transmural (n=6) area of early perfusion defects of the myocardium was detected in 15 of 16 patients (94%) on early-phase CT images. Variable delayed myocardial enhancement patterns on late-phase CT images were observed in 12 patients (75%): (1) subendocardial residual perfusion defect and subepicardial late enhancement (n=6); (2) transmural late enhancement (n=1); (3) isolated subendocardial late enhancement (n=1); and (4) isolated subendocardial residual perfusion defect (n=2). On catheter angiography, 14 of 15 corresponding coronary arteries showed significant stenosis. CONCLUSION: Variable abnormal myocardial enhancement pattern was seen on two-phase, contrast-enhanced ECG-gated MDCT in patients with AMI. Assessment of myocardial attenuation on CT angiography gives additional information of the location and extent of infarction

  5. Dynamic Contrast-Enhanced MRI of Cervical Cancers: Temporal Percentile Screening of Contrast Enhancement Identifies Parameters for Prediction of Chemoradioresistance

    International Nuclear Information System (INIS)

    Andersen, Erlend K.F.; Hole, Knut Håkon; Lund, Kjersti V.; Sundfør, Kolbein; Kristensen, Gunnar B.; Lyng, Heidi; Malinen, Eirik

    2012-01-01

    Purpose: To systematically screen the tumor contrast enhancement of locally advanced cervical cancers to assess the prognostic value of two descriptive parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Methods and Materials: This study included a prospectively collected cohort of 81 patients who underwent DCE-MRI with gadopentetate dimeglumine before chemoradiotherapy. The following descriptive DCE-MRI parameters were extracted voxel by voxel and presented as histograms for each time point in the dynamic series: normalized relative signal increase (nRSI) and normalized area under the curve (nAUC). The first to 100th percentiles of the histograms were included in a log-rank survival test, resulting in p value and relative risk maps of all percentile–time intervals for each DCE-MRI parameter. The maps were used to evaluate the robustness of the individual percentile–time pairs and to construct prognostic parameters. Clinical endpoints were locoregional control and progression-free survival. The study was approved by the institutional ethics committee. Results: The p value maps of nRSI and nAUC showed a large continuous region of percentile–time pairs that were significantly associated with locoregional control (p < 0.05). These parameters had prognostic impact independent of tumor stage, volume, and lymph node status on multivariate analysis. Only a small percentile–time interval of nRSI was associated with progression-free survival. Conclusions: The percentile–time screening identified DCE-MRI parameters that predict long-term locoregional control after chemoradiotherapy of cervical cancer.

  6. Contrast-enhanced ultrasound evaluation of hepatic microvascular changes in liver diseases.

    Science.gov (United States)

    Ridolfi, Francesco; Abbattista, Teresa; Busilacchi, Paolo; Brunelli, Eugenio

    2012-10-07

    To assess if software assisted-contrast-enhanced ultrasonography (CEUS) provides reproducible perfusion parameters of hepatic parenchyma in patients affected by chronic liver disease. Forty patients with chronic viral liver disease, with (n = 20) or without (n = 20) cirrhosis, and 10 healthy subjects underwent CEUS and video recordings of each examination were then analysed with Esaote's Qontrast software. CEUS dedicated software Qontrast was used to determine peak (the maximum signal intensity), time to peak (TTP), region of blood value (RBV) proportional to the area under the time-intensity curve, mean transit time (MTT) measured in seconds and region of blood flow (RBF). Qontrast-assisted CEUS parameters displayed high inter-observer reproducibility (κ coefficients of 0.87 for MTT and 0.90 TTP). When the region of interest included a main hepatic vein, Qontrast-calculated TTP was significantly shorter in cirrhotic patients (vs non-cirrhotics and healthy subjects) (71.0 ± 11.3 s vs. 82.4 ± 15.6 s, 86.3 ± 20.3 s, P < 0.05). MTTs in the patients with liver cirrhosis were significantly shorter than those of controls (111.9 ± 22.0 s vs. 139.4 ± 39.8 s, P < 0.05), but there was no significant difference between the cirrhotic and non-cirrhotic groups (111.9 ± 22.0 s vs. 110.3 ± 14.6 s). Peak enhancement in the patients with liver cirrhosis was also higher than that observed in controls (23.9 ± 5.9 vs. 18.9 ± 7.1, P = 0.05). There were no significant intergroup differences in the RBVs and RBFs. Qontrast-assisted CEUS revealed reproducible differences in liver perfusion parameters during the development of hepatic fibrogenesis.

  7. Limitations of Single Slice Dynamic Contrast Enhanced MR in Pharmacokinetic Modeling of Bone Sarcomas

    Energy Technology Data Exchange (ETDEWEB)

    Toms, Andoni P. (Dept. of Radiology, The Norfolk and Norwich Univ. Hospital, Norwich, Norfolk (United Kingdom)); White, Lawrence M.; Bleakney, Robert R. (Dept. of Medical Imaging, Mount Sinai Hospital, Toronto, ON (Canada)); Kandel, Rita (Dept. of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, ON (Canada)); Noseworthy, Michael (Health Sciences Centre, Faculty of Health Sciences, McMaster Univ., Hamilton, ON (Canada)); Lee, Shepstone (Institute of Health, Univ. of East Anglia, Norwich, Norfolk (United Kingdom)); Blackstein, Martin E. (Dept. of Oncology, Mount Sinai Hospital, Toronto, ON (Canada)); Wunder, Jay (Musculoskeletal Oncology Unit, Mount Sinai Hospital, Toronto, ON (Canada))

    2009-06-15

    Background: Single slice dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) appears to provide perfusion data about sarcomas in vivo that correlate with tumor necrosis on equivalent pathological sections. However, sarcomas are heterogeneous and therefore single slice DCE-MRI may not correlate with total tumor necrosis. Purpose: To determine whether changes in pharmacokinetic modeling of DCE-MRI, during chemotherapy for primary bone sarcomas correlated with histological measures of total tumor necrosis. Material and Methods: Twelve patients with appendicular primary bone sarcomas were included in the study. Each patient had DCE-MRI before, and after completion, of pre-operative chemotherapy. The mean arterial slope (A), endothelial permeability coefficient (Ktrans), and extravascular extracellular volume (Ve) were derived from each data set using a modified two compartment pharmacokinetic model. Total tumor necrosis rates were compared with changes in A, Ktrans, and Ve. Results: Six patients had total tumor necrosis of =90% and six had a measure of <90%. The median percentage changes in A, Ktrans, and Ve for the =90% necrosis group were -52.5% (-83 to 6), -66% (-82 to 26), and 23.5% (-26 to 40), respectively. For the <90% necrosis group, A = - 35% (-75 to 132), Ktrans= - 53 (-66 to 149) and Ve= - 14.5% (-42 to 40). One patient with >90% necrosis had increases in all three measures. Comparison of the two groups generated P-values of 0.699 for A, 0.18 for Ktrans, and 0.31 for Ve. Conclusion: There was no statistically significant correlation between changes in pharmacokinetic perfusion parameters and total tumor necrosis. When using single slice DCE-MRI heterogeneous histology of primary bone sarcomas and repair mediated angiogenesis might both be confounding factors

  8. Contrast-enhanced fluorodeoxyglucose positron emission tomography/contrast-enhanced computed tomography in mediastinal T-cell lymphoma with superior vena cava syndrome

    International Nuclear Information System (INIS)

    Santhosh, Sampath; Gorla, Arun Kumar Reddy; Bhattacharya, Anish; Varma, Subhash Chander; Mittal, Bhagwant Rai

    2016-01-01

    Positron emission tomography-computed tomography (PET/CT) is a routine investigation for the staging of lymphomas. Contrast-enhanced computed tomography is mandatory whenever parenchymal lesions, especially in the liver and spleen are suspected. We report a rare case of primary mediastinal T-cell lymphoma evaluated with contrast-enhanced PET/CT that showed features of superior vena cava syndrome

  9. Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

    International Nuclear Information System (INIS)

    Koenigkam-Santos, Marcel; Optazaite, Elzbieta; Sommer, Gregor; Safi, Seyer; Heussel, Claus Peter; Kauczor, Hans-Ulrich

    2015-01-01

    To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions

  10. Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Koenigkam-Santos, Marcel, E-mail: marcelk46@yahoo.com.br [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Radiology Department, German Cancer Research Center (Deutsches Krebsforschungszentrum – DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Radiology, University Hospital of the School of Medicine of Ribeirao Preto, University of Sao Paulo, Avenida Bandeirantes 3900, Campus Universitario Monte Alegre, 14048 900 Ribeirao Preto, Sao Paulo (Brazil); Optazaite, Elzbieta, E-mail: optazaite@andrulis.eu [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Sommer, Gregor, E-mail: gregor.sommer@usb.ch [Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel (Switzerland); Safi, Seyer, E-mail: seyer.safi@gmail.com [Surgery Department, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Heussel, Claus Peter, E-mail: heussel@uni-heidelberg.de [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); Kauczor, Hans-Ulrich, E-mail: hans-ulrich.kauczor@med.uni-heidelberg.de [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); and others

    2015-01-15

    To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions.

  11. Alterations in renal morphology and function after ESWL therapy: evaluation with dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Krestin, G.P.; Fischbach, R.; Vorreuther, R.; Schulthess, G.K. von

    1993-01-01

    Contrast-enhanced gradient-echo MRI was used to evaluate morphological and functional alterations in the kidneys after extracorporeal shock wave lithotripsy (ESWL). Dynamic MRI with a temporal resolution of 10 s per image was performed by repeated imaging in the coronal plane after administration of gadolinium-DTPA (0.1 mmol/kg) before and after ESWL for renal calculi in 25 patients. Before ESWL 22 patients had normally functioning kidneys, characterised by a marked decrease in signal intensity in the renal medulla 30-40 s after the onset of cortical perfusion. After ESWL 8 patients had functional abnormalities: in 2 cases the medullary signal decrease was disturbed throughout the whole organ, while 6 kidneys demonstrated regional loss of concentrating ability in the medulla. Morphological alterations (oedema with blurred contours and loss of corticomedullary differentiation; parenchymal haemorrhage and haemorrhage in a cortical cyst; subcapsular, perirenal and pararenal haematoma) were detected in 9 cases. Haemorrhage was encountered more often after administration of more than 2500 shock waves; however, no such correlation was seen in the kidneys with functional disturbances following ESWL therapy. MRI proved to be a sensitive method for the assessment of morphological and functional alterations after ESWL, but longer follow-up studies are required to identify the clinical impact of these early changes. (orig.)

  12. Alterations in renal morphology and function after ESWL therapy: evaluation with dynamic contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Krestin, G.P. [Dept. of Medical Radiology, University Hospital Zurich (Switzerland); Fischbach, R. [Dept. of Radiology, Univ. of Cologne (Germany); Vorreuther, R. [Dept. of Urology, Univ. of Cologne (Germany); Schulthess, G.K. von [Dept. of Medical Radiology, University Hospital Zurich (Switzerland)

    1993-06-01

    Contrast-enhanced gradient-echo MRI was used to evaluate morphological and functional alterations in the kidneys after extracorporeal shock wave lithotripsy (ESWL). Dynamic MRI with a temporal resolution of 10 s per image was performed by repeated imaging in the coronal plane after administration of gadolinium-DTPA (0.1 mmol/kg) before and after ESWL for renal calculi in 25 patients. Before ESWL 22 patients had normally functioning kidneys, characterised by a marked decrease in signal intensity in the renal medulla 30-40 s after the onset of cortical perfusion. After ESWL 8 patients had functional abnormalities: in 2 cases the medullary signal decrease was disturbed throughout the whole organ, while 6 kidneys demonstrated regional loss of concentrating ability in the medulla. Morphological alterations (oedema with blurred contours and loss of corticomedullary differentiation; parenchymal haemorrhage and haemorrhage in a cortical cyst; subcapsular, perirenal and pararenal haematoma) were detected in 9 cases. Haemorrhage was encountered more often after administration of more than 2500 shock waves; however, no such correlation was seen in the kidneys with functional disturbances following ESWL therapy. MRI proved to be a sensitive method for the assessment of morphological and functional alterations after ESWL, but longer follow-up studies are required to identify the clinical impact of these early changes. (orig.)

  13. Real-time contrast-enhanced ultrasound in diagnosing of focal spleen lesions

    International Nuclear Information System (INIS)

    Yu Xiaoling; Yu Jie; Liang Ping; Liu Fangyi

    2012-01-01

    Objective: To investigate the features of focal spleen lesions (FSLs) on contrast-enhanced ultrasound (CEUS) imaging. Materials and methods: CEUS with a blot injection of SonoVue was performed in 48 patients with 75 FSLs (median diameter 2.6 cm) and their perfusion characteristics were analyzed by using contrast pulse sequences (CPS) technique. Results: Among 19 malignant lesions (10 metastases, 7 lymphoma, 1 hemangiosarcoma, 1 epithelioid hemangioendothelioma) and 56 benign lesion (23 hemangiomas, 14 cysts, 8 infarctions, 4 splenic ruptures, 3 tuberculosis, 2 abscess, 1 pseudoaneurysm, 1 lymphangioma), 25 benign lesions were demonstrated nonenhancement. For malignancy, 50.0% (5/10) metastases and 57.1% (4/7) lymphomas were showed hypoenhancement in the arterial phase, and 18 (94.7%) of malignant lesions were hypo-enhancement in the parenchymal phase. Among 31 benign lesions with enhancement, 27 (87.1%) were showed isoenhancement or hyperenhancement in the arterial phase and 22 (71.0%) lesions were isoenhancement or hyperenhancement in the parenchymal phase. The sensitivity, specificity and accuracy of diagnosis for FSLs were 91.1%, 95.0% and 92.0% for CEUS and 75.0%, 84.2% and 77.3% respectively, for the conventional baseline ultrasound (BUS). Conclusion: Real-time CEUS can provide valuable information for the diagnosis and differential diagnosis of FSLs.

  14. Recent advances in contrast-enhanced magnetic resonance angiography

    International Nuclear Information System (INIS)

    Meaney, J.F.M.; Goyen, M.

    2007-01-01

    Magnetic resonance angiography (MRA) provides a means of visualizing vascular structures noninvasively and is increasingly replacing conventional X-ray angiography in routine use. Contrast-enhanced MRA (CE-MRA), in which gadolinium contrast agents are used to shorten the T1 relaxation, offers increased resolution and higher signal-to-noise ratio compared with earlier flow-dependent [time-of-flight (TOF) or phase-contrast (PC)] techniques. Currently available contrast agents differ in their ability to lower T1 values, and hence the choice of contrast agent is an important consideration in the successful use of CE-MRA. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first of a new class of intravascular contrast agents. This agent is extensively (approximately 85%) and reversibly bound to human serum albumin and is retained within the vasculature thus allowing steady-state imaging to be perform-ed. An additional benefit is that gado0fosveset offers higher relaxivity compared with other contrast agents, thus giving a lower blood T1 values which also makes it ideal for first-pass imaging. Clinical trials have consistently shown that gadofosveset enhanced MRA is more sensitive, specific and accurate than time-of-flight MRA, gives fewer uninterpretable scans and affords greater diagnostic confidence. Intravascular contrast agents such as gadofosveset, therefore, offer the potential for improved vascular imaging. (orig.)

  15. Abnormal contrast enhancement after the removal of meningioma

    Energy Technology Data Exchange (ETDEWEB)

    Soutsu, M; Hashimoto, T; Yamaguchi, Y; Sekino, H; Nakamura, N [Jikei Univ., Tokyo (Japan). School of Medicine

    1980-12-01

    Since the introduction of Computerized Tomography (CT) in August, 1976, we have had experience with 20 patients with meningioma. In 10 patients out of the 20, the tumors were removed totally and examined by contrast-enhanced CT pre- and postoperatively. In spite of the total removal of the tumor, however, 5 patients showed an unexpected abnormal enhancement at the operated site after the infusion of a contrast material. These changes were relatively intense, so it was suspected that there were residual tumors. Comparing these 5 cases with the remaining 5 that had no postoperative enhancement, the former cases were shown by operative and angiographical findings to have more adhesion and connecting vessels between tumor and cortex. Since such a postoperative abnormal enhancement is seen along the corticotomy or retracted area after operations for and aneurysm or another lesion, damaged brain tissue was though to be the probable reason for this enhancement. Moreover, the circulatory change caused by cutting the connecting vessels between tumor and cortex was considered to be another reason for the enhancement. This mechanism was also considered to be one reason for the post-meningioma syndrome by El-Banhawy. These postoperative enhancements decreased in density and became obscure within 4 or 8 weeks. Any reappearance of such changes after that period should be examined, carefully to determine whether or not it marks a recurrent tumor.

  16. High-dose contrast-enhanced MRI in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Koudriavtseva, T. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Pozzilli, C. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Di Biasi, C. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy); Iannilli, M. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy); Trasimeni, G. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy); Gasperini, C. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Argentino, C. [Department of Neurosciences, University of Rome ``La Sapienza`` Rome (Italy); Gualdi, G.F. [MR Unit, Clinica Medica 1, University of Rome ``La Sapienza``, Rome (Italy)

    1996-05-01

    Contrast-enhanced MRI is effective for assessing disease activity in multiple sclerosis (MS) and may provide an outcome measure for testing the efficacy of treatment in clinical trials. To compare the sensitivity of high-dose gadolinium-HP-DO3A with that of a standard dose of gadolinium-DTPA, we studied 16 patients with relapsing-remitting MS in the acute phase of the disease. Each underwent two MRI examinations within at most 48 h. The initial MRI study was with a standard dose of gadolinium-DTPA (0.1 mmol/kg), and the second one an experimental dose of gadolinium-HP-DO3A (0.3 mmol/kg). No adverse effects were attributed to the contrast media. The high-dose study revealed more enhancing lesions than the standard-dose study (56 vs 38). This difference was found to be more relevant for infratentorial and small lesions. Furthermore, with the higher dose, there was a marked qualitative improvement in the visibility and delineation of the lesions. (orig.). With 4 figs., 2 tabs.

  17. Influence of hyperosmotic agent (glycerol) in contrast enhancement

    International Nuclear Information System (INIS)

    Moriyama, Takashi; Suzuki, Shigeharu; Nakaoka, Tsutomu

    1981-01-01

    For getting a better contrast enhancement (CE) of computed tomography (CT) in brain tumors, we tried to increase the extravascular iodine concentration. A vailing ourselves of the period of returning water following intravenously administered glycerol, a drip injection of the contrast medium gave a better CE effect than the usual CE. In two benign gliomas, CE with glycerol was much better than CE without glycerol, and in two malignant gliomas and two metastatic tumors, CE with glycerol was better, but not so much better as with the benign tumors. In general, the CE effect in primary brain tumors showed a decreasing pattern, whereas in metastatic brain tumors the best time was 60 minutes after the injection of the contrast material (increasing and decreasing pattern), suggesting an increase in the extravascular iodine and a severe failure of the blood brain barrier. Two cystic malignant gliomas allowed the intravenously injected contrast medium to enter the cysts. It appears that the contrast medium passes through and/or is secreted from the wall of the cyst. (author)

  18. Comparison between breast MRI and contrast-enhanced spectral mammography.

    Science.gov (United States)

    Łuczyńska, Elżbieta; Heinze-Paluchowska, Sylwia; Hendrick, Edward; Dyczek, Sonia; Ryś, Janusz; Herman, Krzysztof; Blecharz, Paweł; Jakubowicz, Jerzy

    2015-05-12

    The main goal of this study was to compare contrast-enhanced spectral mammography (CESM) and breast magnetic resonance imaging (MRI) with histopathological results and to compare the sensitivity, accuracy, and positive and negative predictive values for both imaging modalities. After ethics approval, CESM and MRI examinations were performed in 102 patients who had suspicious lesions described in conventional mammography. All visible lesions were evaluated independently by 2 experienced radiologists using BI-RADS classifications (scale 1-5). Dimensions of lesions measured with each modality were compared to postoperative histopathology results. There were 102 patients entered into CESM/MRI studies and 118 lesions were identified by the combination of CESM and breast MRI. Histopathology confirmed that 81 of 118 lesions were malignant and 37 were benign. Of the 81 malignant lesions, 72 were invasive cancers and 9 were in situ cancers. Sensitivity was 100% with CESM and 93% with breast MRI. Accuracy was 79% with CESM and 73% with breast MRI. ROC curve areas based on BI-RADS were 0.83 for CESM and 0.84 for breast MRI. Lesion size estimates on CESM and breast MRI were similar, both slightly larger than those from histopathology. Our results indicate that CESM has the potential to be a valuable diagnostic method that enables accurate detection of malignant breast lesions, has high negative predictive value, and a false-positive rate similar to that of breast MRI.

  19. Challenges in contrast-enhanced spectral mammography interpretation: artefacts lexicon.

    Science.gov (United States)

    Yagil, Y; Shalmon, A; Rundstein, A; Servadio, Y; Halshtok, O; Gotlieb, M; Sklair-Levy, M

    2016-05-01

    To review and describe commonly encountered artefacts in contrast-enhanced spectral mammography (CESM). This retrospective study included 200 women who underwent CESM examinations for screening and diagnostic purposes. Analysis was performed on the image data sets of these women, comprising of a total of 774 subtracted images. Images were reviewed with focus on the presence of four artefacts: rim ("breast within breast"), ripple (black and white lines), axillary line, and skin-line enhancement (skin-line highlighting). Statistical cross-correlation and association with acquisition parameters (tube current, tube voltage, compression force, breast thickness, paddle size) was compared using Fisher's exact test and t-test. The rim artefact was highly common (97-99%) in every projection. The ripple artefact was increasingly more common on the oblique projections (80-82%) and found to be associated with higher breast thickness values. The axillary line artefact was detected only on oblique projections (63%) and associated with the use of a small compression paddle. The skin-line enhancement artefact was seen in 19-46% of projections. None of the artefacts interfered with image interpretation. Two main artefacts commonly seen on CESM are rim and ripple artefacts. They do not hamper with image interpretation. It is important to be aware of them and prevent misinterpretation of these artefacts as real breast pathology. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  20. Contrast-enhanced spectral mammography in patients with MRI contraindications.

    Science.gov (United States)

    Richter, Vivien; Hatterman, Valerie; Preibsch, Heike; Bahrs, Sonja D; Hahn, Markus; Nikolaou, Konstantin; Wiesinger, Benjamin

    2017-01-01

    Background Contrast-enhanced spectral mammography (CESM) is a novel breast imaging technique providing comparable diagnostic accuracy to breast magnetic resonance imaging (MRI). Purpose To show that CESM in patients with MRI contraindications is feasible, accurate, and useful as a problem-solving tool, and to highlight its limitations. Material and Methods A total of 118 patients with MRI contraindications were examined by CESM. Histology was obtained in 94 lesions and used as gold standard for diagnostic accuracy calculations. Imaging data were reviewed retrospectively for feasibility, accuracy, and technical problems. The diagnostic yield of CESM as a problem-solving tool and for therapy response evaluation was reviewed separately. Results CESM was more accurate than mammography (MG) for lesion categorization (r = 0.731, P < 0.0001 vs. r = 0.279, P = 0.006) and for lesion size estimation (r = 0.738 vs. r = 0.689, P < 0.0001). Negative predictive value of CESM was significantly higher than of MG (85.71% vs. 30.77%, P < 0.0001). When used for problem-solving, CESM changed patient management in 2/8 (25%) cases. Superposition artifacts and timing problems affected diagnostic utility in 3/118 (2.5%) patients. Conclusion CESM is a feasible and accurate alternative for patients with MRI contraindications, but it is necessary to be aware of the method's technical limitations.

  1. Contrast enhancement in the craniopharyngioma cyst wall caused by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Eldevik, O.P.; Gabrielsen, T.O.; Altinok, D. [Univ. of Michigan Medical Center, Ann Arbor, MI (United States). Div. of Neuroradiology

    1998-03-01

    Purpose: To report the occurrence, degree, frequency, and duration of contrast enhancement in the craniopharyngioma cyst wall as caused by irradiation. Material and Methods: Eight patients with cystic craniopharyngiomas had comparable CT or MR studies before and after either external irradiation of the cyst (n=5) or {sup 32}P instillation into the cyst (n=3). Results: A minimal to marked increase in cyst-wall enhancement was seen at 66-157 days after {sup 32}P instillation in 3/3 cases and at 112-495 days after external irradiation in 3/5 cases. The increased enhancement was always associated with a variable interim increase in the thickness of the enhanced cyst wall. Conclusion: CT or MR imaging after the irradiation of cystic craniopharyngiomas usually demonstrated an increase in thickness and enhancement in the cyst wall. Such changes may be due to the irradiation alone and do not necessarily represent infection or increased neoplastic activity. The timing is uncertain as to the earliest possible development of such changes and their maximum duration, but they were seen as early as 66 days post-irradiation and as late as 495 days post-irradiation. (orig.).

  2. Contrast enhancement in the craniopharyngioma cyst wall caused by irradiation

    International Nuclear Information System (INIS)

    Eldevik, O.P.; Gabrielsen, T.O.; Altinok, D.

    1998-01-01

    Purpose: To report the occurrence, degree, frequency, and duration of contrast enhancement in the craniopharyngioma cyst wall as caused by irradiation. Material and Methods: Eight patients with cystic craniopharyngiomas had comparable CT or MR studies before and after either external irradiation of the cyst (n=5) or 32 P instillation into the cyst (n=3). Results: A minimal to marked increase in cyst-wall enhancement was seen at 66-157 days after 32 P instillation in 3/3 cases and at 112-495 days after external irradiation in 3/5 cases. The increased enhancement was always associated with a variable interim increase in the thickness of the enhanced cyst wall. Conclusion: CT or MR imaging after the irradiation of cystic craniopharyngiomas usually demonstrated an increase in thickness and enhancement in the cyst wall. Such changes may be due to the irradiation alone and do not necessarily represent infection or increased neoplastic activity. The timing is uncertain as to the earliest possible development of such changes and their maximum duration, but they were seen as early as 66 days post-irradiation and as late as 495 days post-irradiation. (orig.)

  3. Radiochromic film dosimetry of contrast-enhanced radiotherapy (CERT)

    International Nuclear Information System (INIS)

    Morris, Kevin N; Weil, Michael D; Malzbender, Rainer

    2006-01-01

    Contrast-enhanced radiotherapy (CERT) employs elevated concentrations of high-Z contrast media in targets to dramatically increase the absorbed dose of radiation relative to the surrounding tissues. However, it is difficult to measure the dose enhancement with routine clinical instruments because the photoelectrons and Auger electrons produced by the interaction of kilovoltage x-rays with the contrast agent travel extremely short distances. We have developed a technique utilizing unlaminated radiochromic film to measure the maximum dose enhancement factor attainable in solutions of contrast agent with iodine concentrations ranging from 0% to 37% (w/v). The films were also used to simultaneously measure the dose enhancement and beam attenuation through solutions containing 0%, 5% and 10% iodine (w/v). These depth-dose measurements were made in phantoms representing 3 cm targets located 0 and 4.8 cm deep in acrylic. Higher concentrations of contrast yielded greater dose enhancement and target-to-surface dose ratios, but caused more rapid attenuation of the beam as it traversed the target. The dose distribution across the entire target could be improved by employing multiple beams. These results, using concentrations of contrast that are clinically achievable by intratumoural injection, illustrate the potential of CERT for the specific delivery of high doses of radiation to targets at depth

  4. Cumulative phase delay imaging for contrast-enhanced ultrasound tomography

    International Nuclear Information System (INIS)

    Demi, Libertario; Van Sloun, Ruud J G; Wijkstra, Hessel; Mischi, Massimo

    2015-01-01

    Standard dynamic-contrast enhanced ultrasound (DCE-US) imaging detects and estimates ultrasound-contrast-agent (UCA) concentration based on the amplitude of the nonlinear (harmonic) components generated during ultrasound (US) propagation through UCAs. However, harmonic components generation is not specific to UCAs, as it also occurs for US propagating through tissue. Moreover, nonlinear artifacts affect standard DCE-US imaging, causing contrast to tissue ratio reduction, and resulting in possible misclassification of tissue and misinterpretation of UCA concentration. Furthermore, no contrast-specific modality exists for DCE-US tomography; in particular speed-of-sound changes due to UCAs are well within those caused by different tissue types. Recently, a new marker for UCAs has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental component is in fact observable for US propagating through UCAs, and is absent in tissue. In this paper, tomographic US images based on CPD are for the first time presented and compared to speed-of-sound US tomography. Results show the applicability of this marker for contrast specific US imaging, with cumulative phase delay imaging (CPDI) showing superior capabilities in detecting and localizing UCA, as compared to speed-of-sound US tomography. Cavities (filled with UCA) which were down to 1 mm in diameter were clearly detectable. Moreover, CPDI is free of the above mentioned nonlinear artifacts. These results open important possibilities to DCE-US tomography, with potential applications to breast imaging for cancer localization. (fast track communication)

  5. High-dose contrast-enhanced MRI in multiple sclerosis

    International Nuclear Information System (INIS)

    Koudriavtseva, T.; Pozzilli, C.; Di Biasi, C.; Iannilli, M.; Trasimeni, G.; Gasperini, C.; Argentino, C.; Gualdi, G.F.

    1996-01-01

    Contrast-enhanced MRI is effective for assessing disease activity in multiple sclerosis (MS) and may provide an outcome measure for testing the efficacy of treatment in clinical trials. To compare the sensitivity of high-dose gadolinium-HP-DO3A with that of a standard dose of gadolinium-DTPA, we studied 16 patients with relapsing-remitting MS in the acute phase of the disease. Each underwent two MRI examinations within at most 48 h. The initial MRI study was with a standard dose of gadolinium-DTPA (0.1 mmol/kg), and the second one an experimental dose of gadolinium-HP-DO3A (0.3 mmol/kg). No adverse effects were attributed to the contrast media. The high-dose study revealed more enhancing lesions than the standard-dose study (56 vs 38). This difference was found to be more relevant for infratentorial and small lesions. Furthermore, with the higher dose, there was a marked qualitative improvement in the visibility and delineation of the lesions. (orig.). With 4 figs., 2 tabs

  6. Image fusion for dynamic contrast enhanced magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Leach Martin O

    2004-10-01

    Full Text Available Abstract Background Multivariate imaging techniques such as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI have been shown to provide valuable information for medical diagnosis. Even though these techniques provide new information, integrating and evaluating the much wider range of information is a challenging task for the human observer. This task may be assisted with the use of image fusion algorithms. Methods In this paper, image fusion based on Kernel Principal Component Analysis (KPCA is proposed for the first time. It is demonstrated that a priori knowledge about the data domain can be easily incorporated into the parametrisation of the KPCA, leading to task-oriented visualisations of the multivariate data. The results of the fusion process are compared with those of the well-known and established standard linear Principal Component Analysis (PCA by means of temporal sequences of 3D MRI volumes from six patients who took part in a breast cancer screening study. Results The PCA and KPCA algorithms are able to integrate information from a sequence of MRI volumes into informative gray value or colour images. By incorporating a priori knowledge, the fusion process can be automated and optimised in order to visualise suspicious lesions with high contrast to normal tissue. Conclusion Our machine learning based image fusion approach maps the full signal space of a temporal DCE-MRI sequence to a single meaningful visualisation with good tissue/lesion contrast and thus supports the radiologist during manual image evaluation.

  7. Contrast-Enhanced Endoscopic Ultrasonography for Pancreatic Tumors

    Directory of Open Access Journals (Sweden)

    Yasunobu Yamashita

    2015-01-01

    Full Text Available Objectives. To investigate the usefulness of contrast-enhanced endoscopic ultrasonography (CE-EUS for histological differentiation of pancreatic tumors. Methods. CE-EUS was performed for consecutive patients having a pancreatic solid lesion, and tumors were classified into three vascular patterns (hypervascular, isovascular, and hypovascular at two time phases (early-phase and late-phase. Correlation between vascular patterns and histopathology of resected pancreatic cancer (PC tissues was ascertained. Results. The final diagnoses of 147 examined tumors were PC (n=109, inflammatory mass (n=11, autoimmune pancreatitis (n=9, neuroendocrine tumor (n=8, and others (n=10. In late-phase images, 104 of 109 PCs had the hypovascular pattern, for a diagnostic sensitivity and specificity of 94% and 71%, respectively. Of 28 resected PCs, 10 had isovascular, and 18 hypovascular, patterns on the early-phase image. Early-phase isovascular PCs were more likely to be differentiated than were early-phase hypovascular PCs (6 well and 4 moderately differentiated versus 3 well, 14 moderately, and 1 poorly differentiated, P=0.028. Immunostaining revealed that hypovascular areas of early-phase images reflected heterogeneous tumor cells with fibrous tissue, necrosis, and few vessels. Conclusion. CE-EUS could be useful for distinguishing PC from other solid pancreatic lesions and for histological differentiation of PCs.

  8. Differentiation of focal liver lesions by contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Heintz, P.; Ehrenheim, C.

    1989-01-01

    47 patients with liver tumours (haemangioma, focal nodular hyperplasia, hepatocellular carcinoma) underwent MRI of the liver before and after i.v. injection of 0.2 ml./kg. gadolinium-DTPA in addition to other imaging methods. The demarcation of focal nodular hyperplasia is not influenced by use of the contrast agent as it almost behaves like surrounding normal liver tissue, thus only indirectly facilitating its identification. With regard to liver haemangiomas that show the most intensive uptake of gadolinium-DTPA, the contrast enhanced image does not reach to contrast and sensitivity of a native T 2 -weighted SE image, especially in cases of small haemangiomas. The contrast agent is helpful, however, in the recognition of large cavernous haemangiomas that are partially fibrotic or thrombotic. Emphasis is given to the contrast agent in hepatomas: gadolinium-DTPA presents a pattern of uptake and distribution frequently found in hepatocellular carcinoma providing additional information on the delineation of internal tumour details. (orig.) [de

  9. Contrast-enhanced fast fluid-attenuated inversion recovery MR imaging in patients with brain tumors

    International Nuclear Information System (INIS)

    Kim, Chan Kyo; Na, Dong Gyu; Ryoo, Wook Jae; Byun Hong Sik; Yoon, Hye Kyung; Kim, Jong hyun

    2000-01-01

    To assess the feasibility of contrast-enhanced fast fluid-attenuated inversion recovery (fast FLAIR) MR imaging in patients with brain tumors. This study involved 31 patients with pathologically proven brain tumors and nine with clinically diagnosed metastases. In all patients, T2-weighted, fast FLAIR, images were visual contrast-enhanced T1-weighted MR images were obtained. Contrast-enhanced fast FLAIR images were visually compared with other MR sequences in terms of tumor conspicuity. In order to distinguish tumor and surrounding edema, contrast-enhanced fast FLAIR images were compared with fast FLAIR and T2-weighted images. The tumor-to- white matter contrast-to-noise ratios (CNRs), as demonstrated by T2-weighted, fast FLAIR, contrast-enhanced fast FLAIR and contrast-enhanced T1-weighted imaging, were quantitatively assessed and compared. For the visual assessment of tumor conspicuity, contrast-enhanced fast FLAIR image imaging superior to fast FLAIR in 60% of cases (24/40), and superior to T2-weighted in 70% (28/40). Contrast-enhanced fast FLAIR imaging was inferior to contrast-enhanced T1-weighted in 58% of cases (23/40). For distinguishing between tumor and surrounding edema, contrast-enhanced fast FLAIR imaging was superior to fast FLAIR or T2-weighted in 22 of 27 tumors with peritumoral edema (81%). Quantitatively, CNR was the highest on contrast-enhanced fast FLAIR image and the lowest on fast FLAIR. For the detection of leptomeningeal metastases, contrast-enhanced fast FLAIR was partially superior to contrast-enhanced T1-weighted imaging in two of three high-grade gliomas. Although contrast-enhanced fast FLAIR imaging should not be seen as a replacement for conventional modalities, it provides additional informaton for assessment of the extent of glial cell tumors and leptomeningeal metastases in patients with brain tumors. (author)

  10. Assessment of skeletal muscle microcirculation in type 2 diabetes mellitus using dynamic contrast-enhanced ultrasound: a pilot study.

    Science.gov (United States)

    Amarteifio, Erick; Wormsbecher, Stephanie; Demirel, Serdar; Krix, Martin; Braun, Simone; Rehnitz, Christoph; Delorme, Stefan; Kauczor, Hans-Ulrich; Weber, Marc-André

    2013-09-01

    To investigate muscular micro-perfusion by employing dynamic contrast-enhanced ultrasound (CEUS) and performing transient arterial occlusion in patients with type 2 diabetes mellitus (DM-2). Twenty DM-2 patients (mean age, 58 ± 8.6 years; duration of diabetes, 15.4 ± 12.1 years) and 20 healthy volunteers (mean age, 54 ± 5.4 years) participated. CEUS was applied to the calf, while 4.8 mL of SonoVue(®) was injected intravenously. At the thigh level, arterial occlusion (60 s) was performed. CEUS parameters (tmax, max, AUCpost and m) were evaluated and Pearson-product-moment correlation coefficients were computed. A moderate negative correlation of HbA1c and max was established (-0.53). Max in patients with DM-2 >10 years was 79.89 ± 37.4. Max in patients with DM-2 duration 10 years was 3924.01 ± 1630.52. AUCpost in patients with DM-2 duration <10 years was 6453.59 ± 3206.23 (p = 0.04). Patients with long history of DM-2 present with impaired muscular perfusion. CEUS and transient arterial occlusion may provide appropriate methods for semi-quantitative evaluation of muscular micro-perfusion in patients with DM-2.

  11. The forgotten organ: Contrast enhanced sonography of the spleen

    International Nuclear Information System (INIS)

    Goerg, Christian

    2007-01-01

    Objective: Ultrasound contrast agents in conjunction with contrast specific imaging techniques, are increasingly accepted in clinical use for diagnostic imaging in several organs. Contrast enhanced sonography (CES) of second-generation contrast media have shown a spleen-specific uptake of the microbubble contrast agent. The aim of this review is to illustrate indications for the use of CES in patients with suspected (peri-)splenic pathology. Methods: This review based on the experience of transcutaneous CES in 200 patients with (peri-)splenic pathology diagnosed by B-mode sonography at an internal medicine center. CES studies were performed with a contrast-devoted unit (Acuson, Sequoia, Siemens medical solution) that had contrast-specific, continuous-mode software. A low mechanical index was used. A sulfur hexafluoride-based microbubble contrast medium (Sonovue, Bracco SpA, Milan, Italy) was injected. Results: On our experience, there are several clinical conditions which may show an diagnostic advantage of CES in comparison to B-mode US. CES should be performed to investigate: (1) the perisplenic tumor to diagnose or exclude accessory spleen, (2) the small-sized spleen to diagnose functional asplenia/hyposplenia, (3) the inhomogenous spleen of unknown cause to diagnose focal lesions within the spleen, (4) the incidentally found hypoechoic splenic tumor to diagnose high vascular splenic hemangioma, (5) focal lesions suspect for splenic abscess, hematoma, infarction to confirme diagnosis, and (6) patients with abdominal trauma to diagnose or exclude splenic injuriy. Conclusion: CES is of diagnostic value in several clinical circumstances to diagnose accessory spleen, functional asplenia, small-sized splenic involvement, high vascular splenic hemangioma, and vascular splenic pathology like splenic infarction, splenic abscess, and splenic laceration

  12. The forgotten organ: Contrast enhanced sonography of the spleen

    Energy Technology Data Exchange (ETDEWEB)

    Goerg, Christian [Medizinische Universitaetsklinik, Baldingerstrasse, 35043 Marburg/Lahn (Germany)], E-mail: goergc@med.uni-marburg.de

    2007-11-15

    Objective: Ultrasound contrast agents in conjunction with contrast specific imaging techniques, are increasingly accepted in clinical use for diagnostic imaging in several organs. Contrast enhanced sonography (CES) of second-generation contrast media have shown a spleen-specific uptake of the microbubble contrast agent. The aim of this review is to illustrate indications for the use of CES in patients with suspected (peri-)splenic pathology. Methods: This review based on the experience of transcutaneous CES in 200 patients with (peri-)splenic pathology diagnosed by B-mode sonography at an internal medicine center. CES studies were performed with a contrast-devoted unit (Acuson, Sequoia, Siemens medical solution) that had contrast-specific, continuous-mode software. A low mechanical index was used. A sulfur hexafluoride-based microbubble contrast medium (Sonovue, Bracco SpA, Milan, Italy) was injected. Results: On our experience, there are several clinical conditions which may show an diagnostic advantage of CES in comparison to B-mode US. CES should be performed to investigate: (1) the perisplenic tumor to diagnose or exclude accessory spleen, (2) the small-sized spleen to diagnose functional asplenia/hyposplenia, (3) the inhomogenous spleen of unknown cause to diagnose focal lesions within the spleen, (4) the incidentally found hypoechoic splenic tumor to diagnose high vascular splenic hemangioma, (5) focal lesions suspect for splenic abscess, hematoma, infarction to confirme diagnosis, and (6) patients with abdominal trauma to diagnose or exclude splenic injuriy. Conclusion: CES is of diagnostic value in several clinical circumstances to diagnose accessory spleen, functional asplenia, small-sized splenic involvement, high vascular splenic hemangioma, and vascular splenic pathology like splenic infarction, splenic abscess, and splenic laceration.

  13. Polycystic ovary syndrome: dynamic contrast-enhanced ovary MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, C. Zuhal E-mail: sunarerdem@yahoo.com; Bayar, Ulku; Erdem, L. Oktay; Barut, Aykut; Gundogdu, Sadi; Kaya, Erdal

    2004-07-01

    Objective: to determine the enhancement behaviour of the ovaries in women with polycystic ovary syndrome (PCOS) by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to compare these data with those of normal ovulating controls. Method: 24 women with PCOS and 12 controls underwent DCE-MR imaging. Dynamic images were acquired before and after injection of a contrast bolus at 30 s and the min of 1, 2, 3, 4 and 5. On postprocessing examination: (i) the ovarian volumes; (ii) the signal intensity value of each ovary per dynamic study; (iii) early-phase enhancement rate; (iv) time to peak enhancement (T{sub p}); and (v) percentage of washout of 5th min were determined. Data of the ovaries of the women with PCOS and controls were compared with Mann-Whitney U-test. Results: the mean values of T{sub p} were found to be significantly lower in women with PCOS than in controls (p<0.05). On the other hand, the mean values of ovarian volume, the early-phase enhancement rate, and percentage of washout of 5th min of ovaries were significantly higher in PCOS patients (p<0.05). Examination of the mean signal intensity-time curve revealed the ovaries in women with PCOS showed a faster and greater enhancement and wash-out. Conclusion: the enhancement behaviour of ovaries of women with PCOS may be significantly different from those of control subjects on DCE-MR imaging examination. In our experience, it is a valuable modality to highlight the vascularization changes in ovarian stroma with PCOS. We believe that improved DCE-MR imaging techniques may also provide us additional parameters in the diagnosis and treatment strategies of PCOS.

  14. Usefulness of contrast enhanced cardiac computed tomography in myocardial infarction

    International Nuclear Information System (INIS)

    Morooka, Nobuhiro; Yamada, Zenju; Watanabe, Shigeru

    1982-01-01

    Contrast enhanced cardiac computed tomography (CECT) was performed in 33 patients with transmural myocardial infarction. The anterior wall thickness assessed by CECT was well correlated with that by left ventriculography in RAO projection. When the septal wall thickness was compared between ECG gated and non-gated CECT images, the septal wall thickness by non-gated CECT showed a close coincidence with the diastolic wall thickness by ECG gated CECT. In all patients, the thickness of the septal, anterior and postero-lateral walls was measured. The mean wall thickness in patients of antero-septal infarction was 9.0 +- 1.9 mm for the septal wall, 6.3 +- 1.3 mm for the anterior wall, and 10.0 +- 2.1 mm for the postero-lateral wall. In patients of infero-lateral infarction, the mean wall thickness was 12.2 +- 1.7 mm for the septal wall, 10.8 +- 1.6 mm for the anterior wall and 8.9 +- 1.2 mm for the postero-lateral wall. A filling defect was revealed in the infarcted area when CECT was performed in patients with acute myocardial infarction within 1 week from the onset, and late enhancement was demonstrated by plain CT performed 10 min later. Left ventricular aneurysms were noted in 16 of 23 patients of anteroseptal infarction, and 8 of these 16 had mural thrombi in the left ventricle. Coronary artery calcification was found in 11 of 33 myocardial infarction patients. In patients with aortocoronary bypass graft, the sequential scan (dynamic scan) was shown to be a useful non-invasive method because it showed whether the graft was patent or not. (J.P.N.)

  15. Contrast-enhanced endoscopic ultrasonography in digestive diseases.

    Science.gov (United States)

    Hirooka, Yoshiki; Itoh, Akihiro; Kawashima, Hiroki; Ohno, Eizaburo; Itoh, Yuya; Nakamura, Yosuke; Hiramatsu, Takeshi; Sugimoto, Hiroyuki; Sumi, Hajime; Hayashi, Daijiro; Ohmiya, Naoki; Miyahara, Ryoji; Nakamura, Masanao; Funasaka, Kohei; Ishigami, Masatoshi; Katano, Yoshiaki; Goto, Hidemi

    2012-10-01

    Contrast-enhanced endoscopic ultrasonography (CE-EUS) was introduced in the early 1990s. The concept of the injection of carbon dioxide microbubbles into the hepatic artery as a contrast material (enhanced ultrasonography) led to "endoscopic ultrasonographic angiography". After the arrival of the first-generation contrast agent, high-frequency (12 MHz) EUS brought about the enhancement of EUS images in the diagnosis of pancreatico-biliary diseases, upper gastrointestinal (GI) cancer, and submucosal tumors. The electronic scanning endosonoscope with both radial and linear probes enabled the use of high-end ultrasound machines and depicted the enhancement of both color/power Doppler flow-based imaging and harmonic-based imaging using second-generation contrast agents. Many reports have described the usefulness of the differential diagnosis of pancreatic diseases and other abdominal lesions. Quantitative evaluation of CE-EUS images was an objective method of diagnosis using the time-intensity curve (TIC), but it was limited to the region of interest. Recently developed Inflow Time Mapping™ can be generated from stored clips and used to display the pattern of signal enhancement with time after injection, offering temporal difference of contrast agents and improved tumor characterization. On the other hand, three-dimensional CE-EUS images added new information to the literature, but lacked positional information. Three-dimensional CE-EUS with accurate positional information is awaited. To date, most reports have been related to pancreatic lesions or lymph nodes. Hemodynamic analysis might be of use for diseases in other organs: upper GI cancer diagnosis, submucosal tumors, and biliary disorders, and it might also provide functional information. Studies of CE-EUS in diseases in many other organs will increase in the near future.

  16. Contrast-enhanced peripheral MRA. Technique and contrast agents

    International Nuclear Information System (INIS)

    Nielsen, Yousef W.; Thomsen, Henrik S.

    2012-01-01

    In the last decade contrast-enhanced magnetic resonance angiography (CE-MRA) has gained wide acceptance as a valuable tool in the diagnostic work-up of patients with peripheral arterial disease. This review presents current concepts in peripheral CE-MRA with emphasis on MRI technique and contrast agents. Peripheral CE-MRA is defined as an MR angiogram of the arteries from the aortic bifurcation to the feet. Advantages of CE-MRA include minimal invasiveness and lack of ionizing radiation. The basic technique employed for peripheral CE-MRA is the bolus-chase method. With this method a paramagnetic MRI contrast agent is injected intravenously and T1-weighted images are acquired in the subsequent arterial first-pass phase. In order to achieve high quality MR angiograms without interfering venous contamination or artifacts, a number of factors need to be taken into account. This includes magnetic field strength of the MRI system, receiver coil configuration, use of parallel imaging, contrast bolus timing technique, and k-space filling strategies. Furthermore, it is possible to optimize peripheral CE-MRA using venous compression techniques, hybrid scan protocols, time-resolved imaging, and steady-state MRA. Gadolinium(Gd)-based contrast agents are used for CE-MRA of the peripheral arteries. Extracellular Gd agents have a pharmacokinetic profile similar to iodinated contrast media. Accordingly, these agents are employed for first-pass MRA. Blood-pool Gd-based agents are characterized by prolonged intravascular stay, due to macromolecular structure or protein binding. These agents can be used for first-pass, as well as steady-state MRA. Some Gd-based contrast agents with low thermodynamic stability have been linked to development of nephrogenic systemic fibrosis in patients with severe renal insufficiency. Using optimized technique and a stable MRI contrast agent, peripheral CE-MRA is a safe procedure with diagnostic accuracy close to that of conventional catheter X

  17. TMJ disorders and pain: Assessment by contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Farina, Davide; Bodin, Christiane; Gandolfi, Silvia; De Gasperi, Werner; Borghesi, Andrea; Maroldi, Roberto

    2009-01-01

    Though magnetic resonance (MRI) is a widely accepted standard for the assessment of patients with temporomandibular joint (TMJ) disorders, efforts to correlate symptoms to MRI findings have often given controversial results. Aim of this study was to investigate the correlation between TMJ pain and findings of contrast-enhanced MRI. Thirty-eight consecutive patients with TMJ dysfunction syndrome (study group) were examined with MRI. Protocol included T2 turbo spin-echo sequence, T1 spin-echo sequence, and T2 gradient-echo (acquired with closed jaw, at intermediate and maximal opening). Post-contrast phase was obtained through a fat sat 3D T1 gradient-echo sequence (VIBE). Post-contrast findings in the study group were matched with those obtained in a control group of 33 patients submitted to MRI of the paranasal sinuses. Statistically significant difference was found between condylar medullary bone enhancement in painful TMJ, in painless TMJ and control group. In addition the average thickness of joint soft tissue enhancement in painful TMJ was superior to painless TMJ (p < 0.0001) and to control group. On multivariate logistic regression analysis, the odds ratio that a painful TMJ showed disk displacement, osteoarthrosis, effusion and JST enhancement were 3.05, 3.18, 1.2 and 11.36, respectively. Though not histologically proven, TMJ enhancement could reflect the presence of inflammation in painful joints. Furthermore, the administration of contrast could be of help for the assessment of patients with orofacial pain, particularly when clinical exploration is insufficient to ascribe the pain to TMJ.

  18. TMJ disorders and pain: Assessment by contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Farina, Davide [Department of Radiology (School of Medicine), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); Bodin, Christiane [Division of Gnathology (School of Dentistry), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); Gandolfi, Silvia [Department of Radiology (School of Medicine), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); De Gasperi, Werner [Division of Gnathology (School of Dentistry), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy); Borghesi, Andrea; Maroldi, Roberto [Department of Radiology (School of Medicine), University of Brescia, Piazzale Spedali Civili 1, 25123 Brescia (Italy)

    2009-04-15

    Though magnetic resonance (MRI) is a widely accepted standard for the assessment of patients with temporomandibular joint (TMJ) disorders, efforts to correlate symptoms to MRI findings have often given controversial results. Aim of this study was to investigate the correlation between TMJ pain and findings of contrast-enhanced MRI. Thirty-eight consecutive patients with TMJ dysfunction syndrome (study group) were examined with MRI. Protocol included T2 turbo spin-echo sequence, T1 spin-echo sequence, and T2 gradient-echo (acquired with closed jaw, at intermediate and maximal opening). Post-contrast phase was obtained through a fat sat 3D T1 gradient-echo sequence (VIBE). Post-contrast findings in the study group were matched with those obtained in a control group of 33 patients submitted to MRI of the paranasal sinuses. Statistically significant difference was found between condylar medullary bone enhancement in painful TMJ, in painless TMJ and control group. In addition the average thickness of joint soft tissue enhancement in painful TMJ was superior to painless TMJ (p < 0.0001) and to control group. On multivariate logistic regression analysis, the odds ratio that a painful TMJ showed disk displacement, osteoarthrosis, effusion and JST enhancement were 3.05, 3.18, 1.2 and 11.36, respectively. Though not histologically proven, TMJ enhancement could reflect the presence of inflammation in painful joints. Furthermore, the administration of contrast could be of help for the assessment of patients with orofacial pain, particularly when clinical exploration is insufficient to ascribe the pain to TMJ.

  19. Dynamic contrast-enhanced MRI evaluation of cerebral cavernous malformations.

    Science.gov (United States)

    Hart, Blaine L; Taheri, Saeid; Rosenberg, Gary A; Morrison, Leslie A

    2013-10-01

    The aim of this study is to quantitatively evaluate the behavior of CNS cavernous malformations (CCMs) using a dynamic contrast-enhanced MRI (DCEMRI) technique sensitive for slow transfer rates of gadolinium. The prospective study was approved by the institutional review board and was HIPPA compliant. Written informed consent was obtained from 14 subjects with familial CCMs (4 men and 10 women, ages 22-76 years, mean 48.1 years). Following routine anatomic MRI of the brain, DCEMRI was performed for six slices, using T1 mapping with partial inversion recovery (TAPIR) to calculate T1 values, following administration of 0.025 mmol/kg gadolinium DTPA. The transfer rate (Ki) was calculated using the Patlak model, and Ki within CCMs was compared to normal-appearing white matter as well as to 17 normal control subjects previously studied. All subjects had typical MRI appearance of CCMs. Thirty-nine CCMs were studied using DCEMRI. Ki was low or normal in 12 lesions and elevated from 1.4 to 12 times higher than background in the remaining 27 lesions. Ki ranged from 2.1E-6 to 9.63E-4 min(-1), mean 3.55E-4. Normal-appearing white matter in the CCM patients had a mean Ki of 1.57E-4, not statistically different from mean WM Ki of 1.47E-4 in controls. TAPIR-based DCEMRI technique permits quantifiable assessment of CCMs in vivo and reveals considerable differences not seen with conventional MRI. Potential applications include correlation with biologic behavior such as lesion growth or hemorrage, and measurement of drug effects.

  20. Polycystic ovary syndrome: dynamic contrast-enhanced ovary MR imaging

    International Nuclear Information System (INIS)

    Erdem, C. Zuhal; Bayar, Ulku; Erdem, L. Oktay; Barut, Aykut; Gundogdu, Sadi; Kaya, Erdal

    2004-01-01

    Objective: to determine the enhancement behaviour of the ovaries in women with polycystic ovary syndrome (PCOS) by dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging and to compare these data with those of normal ovulating controls. Method: 24 women with PCOS and 12 controls underwent DCE-MR imaging. Dynamic images were acquired before and after injection of a contrast bolus at 30 s and the min of 1, 2, 3, 4 and 5. On postprocessing examination: (i) the ovarian volumes; (ii) the signal intensity value of each ovary per dynamic study; (iii) early-phase enhancement rate; (iv) time to peak enhancement (T p ); and (v) percentage of washout of 5th min were determined. Data of the ovaries of the women with PCOS and controls were compared with Mann-Whitney U-test. Results: the mean values of T p were found to be significantly lower in women with PCOS than in controls (p<0.05). On the other hand, the mean values of ovarian volume, the early-phase enhancement rate, and percentage of washout of 5th min of ovaries were significantly higher in PCOS patients (p<0.05). Examination of the mean signal intensity-time curve revealed the ovaries in women with PCOS showed a faster and greater enhancement and wash-out. Conclusion: the enhancement behaviour of ovaries of women with PCOS may be significantly different from those of control subjects on DCE-MR imaging examination. In our experience, it is a valuable modality to highlight the vascularization changes in ovarian stroma with PCOS. We believe that improved DCE-MR imaging techniques may also provide us additional parameters in the diagnosis and treatment strategies of PCOS

  1. Patterns of contrast enhancement in the brain and meninges.

    Science.gov (United States)

    Smirniotopoulos, James G; Murphy, Frances M; Rushing, Elizabeth J; Rees, John H; Schroeder, Jason W

    2007-01-01

    Contrast material enhancement for cross-sectional imaging has been used since the mid 1970s for computed tomography and the mid 1980s for magnetic resonance imaging. Knowledge of the patterns and mechanisms of contrast enhancement facilitate radiologic differential diagnosis. Brain and spinal cord enhancement is related to both intravascular and extravascular contrast material. Extraaxial enhancing lesions include primary neoplasms (meningioma), granulomatous disease (sarcoid), and metastases (which often manifest as mass lesions). Linear pachymeningeal (dura-arachnoid) enhancement occurs after surgery and with spontaneous intracranial hypotension. Leptomeningeal (pia-arachnoid) enhancement is present in meningitis and meningoencephalitis. Superficial gyral enhancement is seen after reperfusion in cerebral ischemia, during the healing phase of cerebral infarction, and with encephalitis. Nodular subcortical lesions are typical for hematogenous dissemination and may be neoplastic (metastases) or infectious (septic emboli). Deeper lesions may form rings or affect the ventricular margins. Ring enhancement that is smooth and thin is typical of an organizing abscess, whereas thick irregular rings suggest a necrotic neoplasm. Some low-grade neoplasms are "fluid-secreting," and they may form heterogeneously enhancing lesions with an incomplete ring sign as well as the classic "cyst-with-nodule" morphology. Demyelinating lesions, including both classic multiple sclerosis and tumefactive demyelination, may also create an open ring or incomplete ring sign. Thick and irregular periventricular enhancement is typical for primary central nervous system lymphoma. Thin enhancement of the ventricular margin occurs with infectious ependymitis. Understanding the classic patterns of lesion enhancement--and the radiologic-pathologic mechanisms that produce them--can improve image assessment and differential diagnosis.

  2. Extent of myocardium at risk for left anterior descending artery, right coronary artery, and left circumflex artery occlusion depicted by contrast-enhanced steady state free precession and T2-weighted short tau inversion recovery magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nordlund, David; Heiberg, Einar; Carlsson, Marcus

    2016-01-01

    Background - Contrast-enhanced steady state free precession (CE-SSFP) and T2-weighted short tau inversion recovery (T2-STIR) have been clinically validated to estimate myocardium at risk (MaR) by cardiovascular magnetic resonance while using myocardial perfusion single-photon emission computed...... tomography as reference standard. Myocardial perfusion single-photon emission computed tomography has been used to describe the coronary perfusion territories during myocardial ischemia. Compared with myocardial perfusion single-photon emission computed tomography, cardiovascular magnetic resonance offers...... to show the main coronary perfusion territories using CE-SSFP and T2-STIR. The good agreement between CE-SSFP and T2-STIR from this study and myocardial perfusion single-photon emission computed tomography from previous studies indicates that these 3 methods depict MaR accurately in individual patients...

  3. Myocardial blood flow estimates from dynamic contrast-enhanced magnetic resonance imaging: three quantitative methods

    Science.gov (United States)

    Borrazzo, Cristian; Galea, Nicola; Pacilio, Massimiliano; Altabella, Luisa; Preziosi, Enrico; Carnì, Marco; Ciolina, Federica; Vullo, Francesco; Francone, Marco; Catalano, Carlo; Carbone, Iacopo

    2018-02-01

    Dynamic contrast-enhanced cardiovascular magnetic resonance imaging can be used to quantitatively assess the myocardial blood flow (MBF), recovering the tissue impulse response function for the transit of a gadolinium bolus through the myocardium. Several deconvolution techniques are available, using various models for the impulse response. The method of choice may influence the results, producing differences that have not been deeply investigated yet. Three methods for quantifying myocardial perfusion have been compared: Fermi function modelling (FFM), the Tofts model (TM) and the gamma function model (GF), with the latter traditionally used in brain perfusion MRI. Thirty human subjects were studied at rest as well as under cold pressor test stress (submerging hands in ice-cold water), and a single bolus of gadolinium weighing 0.1  ±  0.05 mmol kg-1 was injected. Perfusion estimate differences between the methods were analysed by paired comparisons with Student’s t-test, linear regression analysis, and Bland-Altman plots, as well as also using the two-way ANOVA, considering the MBF values of all patients grouped according to two categories: calculation method and rest/stress conditions. Perfusion estimates obtained by various methods in both rest and stress conditions were not significantly different, and were in good agreement with the literature. The results obtained during the first-pass transit time (20 s) yielded p-values in the range 0.20-0.28 for Student’s t-test, linear regression analysis slopes between 0.98-1.03, and R values between 0.92-1.01. From the Bland-Altman plots, the paired comparisons yielded a bias (and a 95% CI)—expressed as ml/min/g—for FFM versus TM, -0.01 (-0.20, 0.17) or 0.02 (-0.49, 0.52) at rest or under stress respectively, for FFM versus GF, -0.05 (-0.29, 0.20) or  -0.07 (-0.55, 0.41) at rest or under stress, and for TM versus GF, -0.03 (-0.30, 0.24) or  -0.09 (-0.43, 0.26) at rest or under stress. With the

  4. Combined use of susceptibility weighted magnetic resonance imaging sequences and dynamic susceptibility contrast perfusion weighted imaging to improve the accuracy of the differential diagnosis of recurrence and radionecrosis in high-grade glioma patients.

    Science.gov (United States)

    Kim, Tae-Hyung; Yun, Tae Jin; Park, Chul-Kee; Kim, Tae Min; Kim, Ji-Hoon; Sohn, Chul-Ho; Won, Jae Kyung; Park, Sung-Hye; Kim, Il Han; Choi, Seung Hong

    2017-03-21

    Purpose was to assess predictive power for overall survival (OS) and diagnostic performance of combination of susceptibility-weighted MRI sequences (SWMRI) and dynamic susceptibility contrast (DSC) perfusion-weighted imaging (PWI) for differentiation of recurrence and radionecrosis in high-grade glioma (HGG). We enrolled 51 patients who underwent radiation therapy or gamma knife surgeryfollowed by resection for HGG and who developed new measurable enhancement more than six months after complete response. The lesions were confirmed as recurrence (n = 32) or radionecrosis (n = 19). The mean and each percentile value from cumulative histograms of normalized CBV (nCBV) and proportion of dark signal intensity on SWMRI (proSWMRI, %) within enhancement were compared. Multivariate regression was performed for the best differentiator. The cutoff value of best predictor from ROC analysis was evaluated. OS was determined with Kaplan-Meier method and log-rank test. Recurrence showed significantly lower proSWMRI and higher mean nCBV and 90th percentile nCBV (nCBV90) than radionecrosis. Regression analysis revealed both nCBV90 and proSWMRI were independent differentiators. Combination of nCBV90 and proSWMRI achieved 71.9% sensitivity (23/32), 100% specificity (19/19) and 82.3% accuracy (42/51) using best cut-off values (nCBV90 > 2.07 and proSWMRI≤15.76%) from ROC analysis. In subgroup analysis, radionecrosis with nCBV > 2.07 (n = 5) showed obvious hemorrhage (proSWMRI > 32.9%). Patients with nCBV90 > 2.07 and proSWMRI≤15.76% had significantly shorter OS. In conclusion, compared with DSC PWI alone, combination of SWMRI and DSC PWI have potential to be prognosticator for OS and lower false positive rate in differentiation of recurrence and radionecrosis in HGG who develop new measurable enhancement more than six months after complete response.

  5. Pulmonary MR angiography and perfusion imaging—A review of methods and applications

    Energy Technology Data Exchange (ETDEWEB)

    Johns, Christopher S.; Swift, Andrew J.; Hughes, Paul J.C. [University of Sheffield (United Kingdom); Ohno, Yoshiharu [Division of Functional and Diagnostic Imaging Research, Department of Radiology, KobeUniversity Graduate School of Medicine, Kobe, Hyogo (Japan); Schiebler, Mark [UW-Madison School of Medicine and Public Health, Madison, WI (United States); Wild, Jim M., E-mail: j.m.wild@sheffield.ac.uk [University of Sheffield (United Kingdom)

    2017-01-15

    Highlights: • This article represents an overview of the methodology and clinical applications of pulmonary MRA and perfusion imaging. • Both contrast enhanced and non-contrast enhanced metholodology for MRA and perfusion are covered. • The current clinical uses and future directions of MRA and MR perfusion are discussed. - Abstract: The pulmonary vasculature and its role in perfusion and gas exchange is an important consideration in many conditions of the lung and heart. Currently the mainstay of imaging of the vasculature and perfusion of the lungs lies with CT and nuclear medicine perfusion scans, both of which require ionizing radiation exposure. Improvements in MRI techniques have increased the use of MRI in pulmonary vascular imaging. Here we review MRI methods for imaging the pulmonary vasculature and pulmonary perfusion, both using contrast enhanced and non-contrast enhanced methodology. In many centres pulmonary MR angiography and dynamic contrast enhanced perfusion MRI are now well established in the routine workflow of patients particularly with pulmonary hypertension and thromboembolic disease. However, these imaging modalities offer exciting new directions for future research and clinical use in other respiratory diseases where consideration of pulmonary perfusion and gas exchange can provide insight in to pathophysiology.

  6. Pulmonary MR angiography and perfusion imaging—A review of methods and applications

    International Nuclear Information System (INIS)

    Johns, Christopher S.; Swift, Andrew J.; Hughes, Paul J.C.; Ohno, Yoshiharu; Schiebler, Mark; Wild, Jim M.

    2017-01-01

    Highlights: • This article represents an overview of the methodology and clinical applications of pulmonary MRA and perfusion imaging. • Both contrast enhanced and non-contrast enhanced metholodology for MRA and perfusion are covered. • The current clinical uses and future directions of MRA and MR perfusion are discussed. - Abstract: The pulmonary vasculature and its role in perfusion and gas exchange is an important consideration in many conditions of the lung and heart. Currently the mainstay of imaging of the vasculature and perfusion of the lungs lies with CT and nuclear medicine perfusion scans, both of which require ionizing radiation exposure. Improvements in MRI techniques have increased the use of MRI in pulmonary vascular imaging. Here we review MRI methods for imaging the pulmonary vasculature and pulmonary perfusion, both using contrast enhanced and non-contrast enhanced methodology. In many centres pulmonary MR angiography and dynamic contrast enhanced perfusion MRI are now well established in the routine workflow of patients particularly with pulmonary hypertension and thromboembolic disease. However, these imaging modalities offer exciting new directions for future research and clinical use in other respiratory diseases where consideration of pulmonary perfusion and gas exchange can provide insight in to pathophysiology.

  7. Pulse sequences for contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Graves, Martin J.

    2007-01-01

    The theory and application of magnetic resonance imaging (MRI) pulse sequences following the administration of an exogenous contrast agent are discussed. Pulse sequences are categorised according to the contrast agent mechanism: changes in proton density, relaxivity, magnetic susceptibility and resonant frequency shift. Applications in morphological imaging, magnetic resonance angiography, dynamic imaging and cell labelling are described. The importance of optimising the pulse sequence for each application is emphasised

  8. Contrast-enhanced dedicated breast CT detection of invasive breast cancer preceding mammographic diagnosis

    Directory of Open Access Journals (Sweden)

    Nicolas D. Prionas, MD, PhD

    2015-01-01

    Full Text Available Dedicated breast computed tomography (bCT generates high-resolution, three-dimensional images of the pendent uncompressed breast. Intravenous iodinated contrast during bCT provides additional physiologic information. In this case, a 10.0-mm invasive ductal carcinoma was visualized using contrast-enhanced breast CT one year before mammographic detection. Mammography four months before bCT was negative. The bCT contrast enhancement pattern closely matched the dynamic contrast-enhanced MRI obtained after diagnosis. Lesion enhancement at contrast-enhanced breast CT matched previously published enhancement values of breast cancer. Contrast-enhanced dedicated bCT provided high-resolution tomographic images and physiologic contrast enhancement data that facilitated the detection of an early breast cancer.

  9. Quantification of regional cerebral blood flow and volume with dynamic susceptibility contrast-enhanced MR imaging.

    Science.gov (United States)

    Rempp, K A; Brix, G; Wenz, F; Becker, C R; Gückel, F; Lorenz, W J

    1994-12-01

    Quantification of regional cerebral blood flow (rCBF) and volume (rCBV) with dynamic magnetic resonance (MR) imaging. After bolus administration of a paramagnetic contrast medium, rapid T2*-weighted gradient-echo images of two sections were acquired for the simultaneous creation of concentration-time curves in the brain-feeding arteries and in brain tissue. Absolute rCBF and rCBV values were determined for gray and white brain matter in 12 subjects with use of principles of the indicator dilution theory. The mean rCBF value in gray matter was 69.7 mL/min +/- 29.7 per 100 g tissue and in white matter, 33.6 mL/min +/- 11.5 per 100 g tissue; the average rCBV was 8.0 mL +/- 3.1 per 100 g tissue and 4.2 mL +/- 1.0 per 100 g tissue, respectively. An age-related decrease in rCBF and rCBV for gray and white matter was observed. Preliminary data demonstrate that the proposed technique allows the quantification of rCBF and rCBV. Although the results are in good agreement with data from positron emission tomography studies, further evaluation is needed to establish the validity of method.

  10. Volumetric dynamic contrast enhanced Computed Tomography (DCE-CT) for preoperative assessment of the vascularity of spinal metastases

    DEFF Research Database (Denmark)

    Lauridsen, Carsten Ammitzbøl

    Purpose To investigate the feasibility of measuring and grading the vascularity of spinal metastases using dynamic contrast enhanced CT (DCE-CT). Materials and methods Prior to surgical treatment of symptomatic metastatic spinal cord compression, 20 patients were examined using DCE-CT. The 320......–detector row CT scanner allowed a volumetric acquisition over a range of 16 cm, covering three to four vertebrae. Image analysis was performed at a dedicated workstation, encompassing quantitative and qualitative measurement of the arterial flow (AF) in mL/min/100mL of the vertebrae. The perfusion values...... were analysed using a single input, maximum slope model. The AF assessed by DCE-CT of affected and non-affected vertebrae will be compared, and furthermore, the correlation between AF and intraoperative blood loss will be examined. Results Preliminary results for 5 patients: In two patients the AF...

  11. Magnetic susceptibility imaging with a nonionic contrast agent

    International Nuclear Information System (INIS)

    Cacheris, W.; Rocklage, S.M.; Quay, S.; Dow, W.; Love, D.; Worah, D.; Lim, K.

    1988-01-01

    The magnetic susceptibility mechanism for MR imaging contrast enhancement has the advantage of providing useful information, such as cerebral blood flow, without crossing the blood-brain barrier. In this paper the authors report the use of a highly effective, relatively nontoxic chelate as a magnetic susceptibility agent. Dy-DTPA-bis(methylamide) (Dy-DTPA-BMA) has an extremely low acute toxicity (LD-50, intravenous, mice ∼ 40 mmol/kg). Doses of 1 mmol/kg and 2 mmol/kg Dy-DTPA-BMA lowered the initial signal intensity 63% to 57%, respectively. The utility of this technique in detecting areas of reduced blood flow within the brain was demonstrated by imaging a rabbit with a cerebral perfusion deficit

  12. Contrast-enhanced ultrasonography of hepatocellular carcinoma: Correlation between quantitative parameters and arteries in neoangiogenesis or sinusoidal capillarization

    International Nuclear Information System (INIS)

    Pei Xiaoqing; Liu Longzhong; Zheng Wei; Cai Muyan; Han Feng; He Jiehua; Li Anhua; Chen Minshan

    2012-01-01

    Objective: The quantitative parameters in contrast-enhanced ultrasonography-time–intensity curve of hepatocellular carcinoma (HCC) were studied to explore their potential importance in monitoring the effects of anti-angiogenic therapy for HCC. Methods: 115 HCC patients were studied with contrast-enhanced ultrasonography-time–intensity curve (CEUS-TIC) and with immunohistochemical analysis of tissue sections. The CEUS images were analyzed off-line to obtained quantitative parameters including maximum of intensity (IMAX), rise time (RT), time to peak (TTP), mean transit time (mTT), rise slope (RS), and washout time (WT). Monoclonal antibodies specific for smooth muscle actin and anti-CD34 were used to observe unpaired arteries (UAs) and microvessel area (MVA) of sinusoidal capillarization, respectively. The UAs and MVA of 82 HCC cases were successfully stained. Results: The number of UAs had moderate correlation with RT (r = −0.446), TTP (r = −0.432), and RS (r = 0.431) (P < 0.05), and it had mild correlation with IMAX (r = 0.303) and WT (r = 0.285) (P < 0.05). MVA of sinusoidal capillarization had no correlation with perfusion parameters. Conclusion: Quantitative CEUS-TIC parameters reflecting hemodynamics of tumors are correlated with UAs, but not with MVA, and they might be used to monitor the effects of anti-angiogenic therapy on HCC.

  13. Quantitative contrast enhanced ultrasound of the liver for time intensity curves-Reliability and potential sources of errors.

    Science.gov (United States)

    Ignee, Andre; Jedrejczyk, Maciej; Schuessler, Gudrun; Jakubowski, Wieslaw; Dietrich, Christoph F

    2010-01-01

    Time intensity curves for real-time contrast enhanced low MI ultrasound is a promising technique since it adds objective data to the more subjective conventional contrast enhanced technique. Current developments showed that the amount of uptake in modern targeted therapy strategies correlates with therapy response. Nevertheless no basic research has been done concerning the reliability and validity of the method. Videos sequences of 31 consecutive patients for at least 60s were recorded. Parameters analysed: area under the curve, maximum intensity, mean transit time, perfusion index, time to peak, rise time. The influence of depth, lateral shift as well as size and shape of the region of interest was analysed. The parameters time to peak and rise time showed a good stability in different depths. Overall there was a variation >50% for all other parameters. Mean transit time, time to peak and rise time were stable from 3 to 10cm depths, whereas all other parameters showed only satisfying results at 4-6cm. Time to peak and rise time were stable as well against lateral shifting whereas all other parameters had again variations over 50%. Size and shape of the region of interest did not influence the results. (1) It is important to compare regions of interest, e.g. in a tumour vs. representative parenchyma in the same depths. (2) Time intensity curves should not be analysed in a depth of less than 4cm. (3) The parameters area under the curve, perfusion index and maximum intensity should not be analysed in a depth more than 6cm. (4) Size and shape of a region of interest in liver parenchyma do not affect time intensity curves. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  14. Features of time–intensity curve parameters of colorectal adenocarcinomas evaluated by double-contrast enhanced ultrasonography: Initial observation

    International Nuclear Information System (INIS)

    Zhuang Hua; Yang Zhigang; Wang Ziqiang; Wang Xiaodong; Chen Huijiao; Zhang Yuanchuan; Luo Yan

    2012-01-01

    Purpose: This study is to investigate the value of double contrast-enhanced ultrasonography (DCEU) in assessing microcirculation of colorectal adenocarcinomas and to describe the perfusion features of the tumours. Material and methods: DCEUS was performed in 42 patients with adenocarcinoma. The time–intensity curve parameters (arrival time (AT), time-to-peak (TTP), peak intensity (PI) and area under the curve (AUC)) within the tumours were extracted. The parameters were compared among the tumours with different CEUS features and stages. Results: The mean values of AT, TTP, PI and AUC of the colorectal adenocarcinomas were 13.68 ± 13.36 s, 32.61 ± 19.56 s, 19.82 ± 16.54 dB and 271.10 ± 159.19 dB s, respectively. In the adenocarcinomas with necrosis, the mean values of AUC was significantly lower than that of the adenocarcinomas without (231.10 ± 219.27 dB s, 278.10 ± 123.20 dB s, p = 0.004). In the adenocarcinomas with necrosis, the AUC and PI of the non-necrotic part were significantly higher than that of the necrotic part (p = 0.007, 0.0025, respectively). AUC increased progressively in the subgroups of T2, T3 and T4 and the difference of AUC between T2 and T4 subgroup was significant (p = 0.008). Conclusions: Double contrast-enhanced ultrasonography is a valuable technique for quantifying tumour vascularity of colorectal adenocarcinomas. AUC was significantly different in the subgroups of different T stage. AUC and PI could reflect the different perfusion status of tumours with or without necrosis.

  15. Quantitative contrast enhanced ultrasound of the liver for time intensity curves-Reliability and potential sources of errors

    Energy Technology Data Exchange (ETDEWEB)

    Ignee, Andre [Department of Internal Medicine and Diagnostic Imaging, Caritas Hospital, Uhlandstr. 7, 97990 Bad Mergentheim (Germany)], E-mail: andre.ignee@gmx.de; Jedrejczyk, Maciej [Department of Diagnostic Imaging, 2nd Division of Medical Faculty, Medical University, Ul. Kondratowicza 8, 03-242 Warsaw (Poland)], E-mail: mjedrzejczyk@interia.pl; Schuessler, Gudrun [Department of Internal Medicine and Diagnostic Imaging, Caritas Hospital, Uhlandstr. 7, 97990 Bad Mergentheim (Germany)], E-mail: gudrunschuessler@gmx.de; Jakubowski, Wieslaw [Department of Diagnostic Imaging, 2nd Division of Medical Faculty, Medical University, Ul. Kondratowicza 8, 03-242 Warsaw (Poland)], E-mail: ewajbmd@go2.pl; Dietrich, Christoph F. [Department of Internal Medicine and Diagnostic Imaging, Caritas Hospital, Uhlandstr. 7, 97990 Bad Mergentheim (Germany)], E-mail: christoph.dietrich@ckbm.de

    2010-01-15

    Introduction: Time intensity curves for real-time contrast enhanced low MI ultrasound is a promising technique since it adds objective data to the more subjective conventional contrast enhanced technique. Current developments showed that the amount of uptake in modern targeted therapy strategies correlates with therapy response. Nevertheless no basic research has been done concerning the reliability and validity of the method. Patients and methods: Videos sequences of 31 consecutive patients for at least 60 s were recorded. Parameters analysed: area under the curve, maximum intensity, mean transit time, perfusion index, time to peak, rise time. The influence of depth, lateral shift as well as size and shape of the region of interest was analysed. Results: The parameters time to peak and rise time showed a good stability in different depths. Overall there was a variation >50% for all other parameters. Mean transit time, time to peak and rise time were stable from 3 to 10 cm depths, whereas all other parameters showed only satisfying results at 4-6 cm. Time to peak and rise time were stable as well against lateral shifting whereas all other parameters had again variations over 50%. Size and shape of the region of interest did not influence the results. Discussion: (1) It is important to compare regions of interest, e.g. in a tumour vs. representative parenchyma in the same depths. (2) Time intensity curves should not be analysed in a depth of less than 4 cm. (3) The parameters area under the curve, perfusion index and maximum intensity should not be analysed in a depth more than 6 cm. (4) Size and shape of a region of interest in liver parenchyma do not affect time intensity curves.

  16. Quantitative contrast enhanced ultrasound of the liver for time intensity curves-Reliability and potential sources of errors

    International Nuclear Information System (INIS)

    Ignee, Andre; Jedrejczyk, Maciej; Schuessler, Gudrun; Jakubowski, Wieslaw; Dietrich, Christoph F.

    2010-01-01

    Introduction: Time intensity curves for real-time contrast enhanced low MI ultrasound is a promising technique since it adds objective data to the more subjective conventional contrast enhanced technique. Current developments showed that the amount of uptake in modern targeted therapy strategies correlates with therapy response. Nevertheless no basic research has been done concerning the reliability and validity of the method. Patients and methods: Videos sequences of 31 consecutive patients for at least 60 s were recorded. Parameters analysed: area under the curve, maximum intensity, mean transit time, perfusion index, time to peak, rise time. The influence of depth, lateral shift as well as size and shape of the region of interest was analysed. Results: The parameters time to peak and rise time showed a good stability in different depths. Overall there was a variation >50% for all other parameters. Mean transit time, time to peak and rise time were stable from 3 to 10 cm depths, whereas all other parameters showed only satisfying results at 4-6 cm. Time to peak and rise time were stable as well against lateral shifting whereas all other parameters had again variations over 50%. Size and shape of the region of interest did not influence the results. Discussion: (1) It is important to compare regions of interest, e.g. in a tumour vs. representative parenchyma in the same depths. (2) Time intensity curves should not be analysed in a depth of less than 4 cm. (3) The parameters area under the curve, perfusion index and maximum intensity should not be analysed in a depth more than 6 cm. (4) Size and shape of a region of interest in liver parenchyma do not affect time intensity curves.

  17. Role of FDG-PET/MRI, FDG-PET/CT, and Dynamic Susceptibility Contrast Perfusion MRI in Differentiating Radiation Necrosis from Tumor Recurrence in Glioblastomas.

    Science.gov (United States)

    Hojjati, Mojgan; Badve, Chaitra; Garg, Vasant; Tatsuoka, Curtis; Rogers, Lisa; Sloan, Andrew; Faulhaber, Peter; Ros, Pablo R; Wolansky, Leo J

    2018-01-01

    To compare the utility of quantitative PET/MRI, dynamic susceptibility contrast (DSC) perfusion MRI (pMRI), and PET/CT in differentiating radiation necrosis (RN) from tumor recurrence (TR) in patients with treated glioblastoma multiforme (GBM). The study included 24 patients with GBM treated with surgery, radiotherapy, and temozolomide who presented with progression on imaging follow-up. All patients underwent PET/MRI and pMRI during a single examination. Additionally, 19 of 24 patients underwent PET/CT on the same day. Diagnosis was established by pathology in 17 of 24 and by clinical/radiologic consensus in 7 of 24. For the quantitative PET/MRI and PET/CT analysis, a region of interest (ROI) was drawn around each lesion and within the contralateral white matter. Lesion to contralateral white matter ratios for relative maximum, mean, and median were calculated. For pMRI, lesion ROI was drawn on the cerebral blood volume (CBV) maps and histogram metrics were calculated. Diagnostic performance for each metric was assessed using receiver operating characteristic curve analysis and area under curve (AUC) was calculated. In 24 patients, 28 lesions were identified. For PET/MRI, relative mean ≥ 1.31 resulted in AUC of .94 with both sensitivity and negative predictive values (NPVs) of 100%. For pMRI, CBV max ≥3.32 yielded an AUC of .94 with both sensitivity and NPV measuring 100%. The joint model utilizing r-mean (PET/MRI) and CBV mode (pMRI) resulted in AUC of 1.0. Our study demonstrates that quantitative PET/MRI parameters in combination with DSC pMRI provide the best diagnostic utility in distinguishing RN from TR in treated GBMs. © 2017 The Authors. Journal of Neuroimaging published by Wiley Periodicals, Inc. on behalf of American Society of Neuroimaging.

  18. Development of a dynamic flow imaging phantom for dynamic contrast-enhanced CT

    International Nuclear Information System (INIS)

    Driscoll, B.; Keller, H.; Coolens, C.

    2011-01-01

    Purpose: Dynamic contrast enhanced CT (DCE-CT) studies with modeling of blood flow and tissue perfusion are becoming more prevalent in the clinic, with advances in wide volume CT scanners allowing the imaging of an entire organ with sub-second image frequency and sub-millimeter accuracy. Wide-spread implementation of perfusion DCE-CT, however, is pending fundamental validation of the quantitative parameters that result from dynamic contrast imaging and perfusion modeling. Therefore, the goal of this work was to design and construct a novel dynamic flow imaging phantom capable of producing typical clinical time-attenuation curves (TACs) with the purpose of developing a framework for the quantification and validation of DCE-CT measurements and kinetic modeling under realistic flow conditions. Methods: The phantom is based on a simple two-compartment model and was printed using a 3D printer. Initial analysis of the phantom involved simple flow measurements and progressed to DCE-CT experiments in order to test the phantoms range and reproducibility. The phantom was then utilized to generate realistic input TACs. A phantom prediction model was developed to compute the input and output TACs based on a given set of five experimental (control) parameters: pump flow rate, injection pump flow rate, injection contrast concentration, and both control valve positions. The prediction model is then inversely applied to determine the control parameters necessary to generate a set of desired input and output TACs. A protocol was developed and performed using the phantom to investigate image noise, partial volume effects and CT number accuracy under realistic flow conditionsResults: This phantom and its surrounding flow system are capable of creating a wide range of physiologically relevant TACs, which are reproducible with minimal error between experiments (σ/μ 2 ) for the input function between 0.95 and 0.98, while the maximum enhancement differed by no more than 3.3%. The

  19. Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases

    International Nuclear Information System (INIS)

    Parmar, Hemant; Sitoh, Y.-Y.; Anand, Pooja; Chua, Violet; Hui, Francis

    2006-01-01

    Purpose: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. Materials and methods: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. Results: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. Conclusion: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis

  20. Diagnositc value of 3D-gradient echo dynamic contrast enhanced MRI in breast cancer

    International Nuclear Information System (INIS)

    Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Shim, Jeong Won

    1997-01-01

    To assess the usefulness of 3D-gradient echo dynamic contrast enhanced MRI (3D-DMRI) in the diagnosis of breast cancer and to determine the most useful parameter for this diagnosis. Using a 1.0T MR unit, (Magnetom, Siemens, Erlaugen, Germany), 3D-DMRI (TR/TE=3D30/12) with Gd-DTPA was performed in 38 cases of breast cancer, 22 of fibroadenoma, and in three normal volunteers. We retrospectively evaluated the findings according to the speed on dynamic study and maximal amount of contrast enhancement during the delayed phase;we calculated the contrast index and morphology of the cancers and compared diagnostic accuracy among these three diagnostic parameters. On conventional spin-echo T1-and T2-weighted images, there was no significant difference of signal intensity between benign fibroadenoma and breast carcinoma. Rapid contrast enhancement (within one minute) was noted in 35 breast cancer lesions (92.1%), but relatively low and slow contrast enhancement (after five minutes) was noted in three such lesions (7.9%). Gradual contrast enhancement was noted in 21 lesions of fibroadenoma(95.5%), but a moderate degree of rapid contrast enhancement (from three to five minutes) was noted in the other case (7.9%). of On the delayed enhanced phase of 3D-DMRI, the maximal amount of contrast enhancement showed no significant difference between fibroadenoma and cancer. On 3D-DMRI, an irregular, spiculated border, with high contrast enhancement was noted in all cases of breast cancer, in particular, irregular thick peripheral contrast enhancement with central necrosis was noted 11cases(28.9%). For the diagnosis of breast cancer, 3D-DMRI is a useful technique. Among the diagnostic criteria of speed, maximal amount of contrast enhancement and morphology, morphologic change after contrast enhancement study was the most useful diagnostic parameter.=20

  1. Diagnositc value of 3D-gradient echo dynamic contrast enhanced MRI in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Shim, Jeong Won [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-10-01

    To assess the usefulness of 3D-gradient echo dynamic contrast enhanced MRI (3D-DMRI) in the diagnosis of breast cancer and to determine the most useful parameter for this diagnosis. Using a 1.0T MR unit, (Magnetom, Siemens, Erlaugen, Germany), 3D-DMRI (TR/TE=3D30/12) with Gd-DTPA was performed in 38 cases of breast cancer, 22 of fibroadenoma, and in three normal volunteers. We retrospectively evaluated the findings according to the speed on dynamic study and maximal amount of contrast enhancement during the delayed phase;we calculated the contrast index and morphology of the cancers and compared diagnostic accuracy among these three diagnostic parameters. On conventional spin-echo T1-and T2-weighted images, there was no significant difference of signal intensity between benign fibroadenoma and breast carcinoma. Rapid contrast enhancement (within one minute) was noted in 35 breast cancer lesions (92.1%), but relatively low and slow contrast enhancement (after five minutes) was noted in three such lesions (7.9%). Gradual contrast enhancement was noted in 21 lesions of fibroadenoma(95.5%), but a moderate degree of rapid contrast enhancement (from three to five minutes) was noted in the other case (7.9%). of On the delayed enhanced phase of 3D-DMRI, the maximal amount of contrast enhancement showed no significant difference between fibroadenoma and cancer. On 3D-DMRI, an irregular, spiculated border, with high contrast enhancement was noted in all cases of breast cancer, in particular, irregular thick peripheral contrast enhancement with central necrosis was noted 11cases(28.9%). For the diagnosis of breast cancer, 3D-DMRI is a useful technique. Among the diagnostic criteria of speed, maximal amount of contrast enhancement and morphology, morphologic change after contrast enhancement study was the most useful diagnostic parameter.=20.

  2. Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, Hemant [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore) and Department of Diagnostic Imaging, Hospital for Sick Children, Toronto (Canada)]. E-mail: parurad@hotmail.com; Sitoh, Y.-Y. [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore); Anand, Pooja [Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng (Singapore); Chua, Violet [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore); Hui, Francis [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore)

    2006-04-15

    Purpose: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. Materials and methods: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. Results: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. Conclusion: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis.

  3. Evaluating automated dynamic contrast enhanced wrist 3 T MRI in healthy volunteers: One-year longitudinal observational study

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Anshul, E-mail: anshul.rastogi@bartshealth.nhs.uk [Kennedy Institute of Rheumatology, Imperial College London (United Kingdom); Kubassova, Olga, E-mail: olga@imageanalysis.org.uk [Image Analysis, Leeds (United Kingdom); Krasnosselskaia, Lada V., E-mail: solaguz@yahoo.com [Imaging Sciences Department, Imperial College London (United Kingdom); Lim, Adrian K.P., E-mail: a.lim@imperial.ac.uk [Department of Radiology, Imperial College Healthcare NHS Trust, London (United Kingdom); Satchithananda, Keshthra, E-mail: keshthra.satchithananda@imperial.nhs.uk [Department of Radiology, Imperial College Healthcare NHS Trust, London (United Kingdom); Boesen, Mikael, E-mail: mikael.boesen@gmail.com [Department of Radiology and the Parker Institute, Frederiksberg and Bispebjerg Hospitals (Denmark); Binks, Michael, E-mail: michael.h.binks@gsk.com [GlaxoSmithKline, Stevenage, SG1 2NY (United Kingdom); Hajnal, Joseph V., E-mail: jo.hajnal@kcl.ac.uk [Imaging Sciences Department, Imperial College London (United Kingdom); Taylor, Peter C., E-mail: peter.taylor@kennedy.ox.ac.uk [Kennedy Institute of Rheumatology, Imperial College London (United Kingdom)

    2013-08-15

    Rational and Objective: Dynamic contrast enhanced (DCE)-MRI has great potential to provide quantitative measure of inflammatory activity in rheumatoid arthritis. There is no current benchmark to establish the stability of signal in the joints of healthy subjects when imaged with DCE-MRI longitudinally, which is crucial so as to differentiate changes induced by treatment from the inherent variability of perfusion measures. The objective of this study was to test a pixel-by-pixel parametric map based approach for analysis of DCE-MRI (Dynamika) and to investigate the variability in signal characteristics over time in healthy controls using longitudinally acquired images. Materials and Methods: 10 healthy volunteers enrolled, dominant wrists were imaged with contrast enhanced 3T MRI at baseline, week 12, 24 and 52 and scored with RAMRIS, DCE-MRI was analysed using a novel quantification parametric map based approach. Radiographs were obtained at baseline and week 52 and scored using modified Sharp van der Heidje method. RAMRIS scores and dynamic MRI measures were correlated. Results: No erosions were seen on radiographs, whereas MRI showed erosion-like changes, low grade bone marrow oedema and low-moderate synovial enhancement. The DCE-MRI parameters were stable (baseline scores, variability) (mean ± st.dev); in whole wrist analysis, ME{sub mean} (1.3 ± 0.07, −0.08 ± 0.1 at week 24) and IRE{sub mean} (0.008 ± 0.004, −0.002 ± 0.005 at week 12 and 24). In the rough wrist ROI, ME{sub mean} (1.2 ± 0.07, 0.04 ± 0.02 at week 52) and IRE{sub mean} (0.001 ± 0.0008, 0.0006 ± 0.0009 at week 52) and precise wrist ROI, ME{sub mean} (1.2 ± 0.09, 0.04 ± 0.04 at week 52) and IRE{sub mean} (0.001 ± 0.0008, 0.0008 ± 0.001 at week 24 and 52). The Dynamic parameters obtained using fully automated analysis demonstrated strong, statistically significant correlations with RAMRIS synovitis scores. Conclusion: The study demonstrated that contrast enhancement does occur in

  4. Brain-wide pathway for waste clearance captured by contrast-enhanced MRI.

    Science.gov (United States)

    Iliff, Jeffrey J; Lee, Hedok; Yu, Mei; Feng, Tian; Logan, Jean; Nedergaard, Maiken; Benveniste, Helene

    2013-03-01

    The glymphatic system is a recently defined brain-wide paravascular pathway for cerebrospinal fluid (CSF) and interstitial fluid (ISF) exchange that facilitates efficient clearance of solutes and waste from the brain. CSF enters the brain along para-arterial channels to exchange with ISF, which is in turn cleared from the brain along para-venous pathways. Because soluble amyloid β clearance depends on glymphatic pathway function, we proposed that failure of this clearance system contributes to amyloid plaque deposition and Alzheimer's disease progression. Here we provide proof of concept that glymphatic pathway function can be measured using a clinically relevant imaging technique. Dynamic contrast-enhanced MRI was used to visualize CSF-ISF exchange across the rat brain following intrathecal paramagnetic contrast agent administration. Key features of glymphatic pathway function were confirmed, including visualization of para-arterial CSF influx and molecular size-dependent CSF-ISF exchange. Whole-brain imaging allowed the identification of two key influx nodes at the pituitary and pineal gland recesses, while dynamic MRI permitted the definition of simple kinetic parameters to characterize glymphatic CSF-ISF exchange and solute clearance from the brain. We propose that this MRI approach may provide the basis for a wholly new strategy to evaluate Alzheimer's disease susceptibility and progression in the live human brain.

  5. Microwave ablation of liver metastases guided by contrast-enhanced ultrasound

    DEFF Research Database (Denmark)

    Lorentzen, T; Skjoldbye, B O; Nolsoe, C P

    2011-01-01

    The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS).......The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS)....

  6. Restoration of myocardial blood flow following percutaneous coronary balloon dilatation and stent implantation: Assessment with qualitative and quantitative contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Sensky, P.R.; Samani, N.J.; Horsfield, M.A.; Cherryman, G.R.

    2002-01-01

    AIM: To examine the serial use of magnetic resonance imaging (MRI) to evaluate regional myocardial perfusion changes following percutaneous coronary angioplasty and stent implantation (PTCA). MATERIALS AND METHODS: Six patients with single vessel coronary artery disease (CAD) underwent contrast-enhanced first pass MRI immediately prior to (visit A) and within 7 days after (visit B) PTCA. Three sequential short axis slices were obtained after gadodiamide (Gd) bolus (0.025 mmol/kg -1 ) at rest and during adenosine. Each short axis was divided radially into eight regions of interest (ROIs). ROIs were anatomically assigned to a coronary artery territory (CAT). Stress and rest qualitative and quantitative (unidirectional extraction fraction constant (K i ); index of myocardial perfusion reserve (MPRI) = stressK i / restK i ) perfusion parameters were determined for ROI supplied by remote and stenosed/stented vessels for each visit. RESULTS: In stented ROIs the number of ROIs demonstrating normal perfusion, as opposed to reversible perfusion deficits, increased. Qualitative perfusion assessment in remote CATs was unchanged. MPRI in stenotic CATs was lower than in remote CATs at visit A (P < 0.001). Following PTCA, MPRI increased in stented CATs (P < 0.001) but was unchanged in remote CATs. CONCLUSION: Restoration of myocardial perfusion following PTCA can be delineated with qualitative and quantitative perfusion MRI. Although at present the investigation is technically complex and not perfectly sensitive or specific, MRI has the potential to be a valuable tool for patient follow-up and evaluation of revascularization strategy efficacy. Sensky, P.R. et al. (2002)

  7. An improved contrast enhancement algorithm for infrared images based on adaptive double plateaus histogram equalization

    Science.gov (United States)

    Li, Shuo; Jin, Weiqi; Li, Li; Li, Yiyang

    2018-05-01

    Infrared thermal images can reflect the thermal-radiation distribution of a particular scene. However, the contrast of the infrared images is usually low. Hence, it is generally necessary to enhance the contrast of infrared images in advance to facilitate subsequent recognition and analysis. Based on the adaptive double plateaus histogram equalization, this paper presents an improved contrast enhancement algorithm for infrared thermal images. In the proposed algorithm, the normalized coefficient of variation of the histogram, which characterizes the level of contrast enhancement, is introduced as feedback information to adjust the upper and lower plateau thresholds. The experiments on actual infrared images show that compared to the three typical contrast-enhancement algorithms, the proposed algorithm has better scene adaptability and yields better contrast-enhancement results for infrared images with more dark areas or a higher dynamic range. Hence, it has high application value in contrast enhancement, dynamic range compression, and digital detail enhancement for infrared thermal images.

  8. Improved visualization of delayed perfusion in lung MRI

    International Nuclear Information System (INIS)

    Risse, Frank; Eichinger, Monika; Kauczor, Hans-Ulrich; Semmler, Wolfhard; Puderbach, Michael

    2011-01-01

    Introduction: The investigation of pulmonary perfusion by three-dimensional (3D) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was proposed recently. Subtraction images are generated for clinical evaluation, but temporal information is lost and perfusion defects might therefore be masked in this process. The aim of this study is to demonstrate a simple analysis strategy and classification for 3D-DCE-MRI perfusion datasets in the lung without omitting the temporal information. Materials and methods: Pulmonary perfusion measurements were performed in patients with different lung diseases using a 1.5 T MR-scanner with a time-resolved 3D-GRE pulse sequence. 25 3D-volumes were acquired after iv-injection of 0.1 mmol/kg KG Gadolinium-DTPA. Three parameters were determined for each pixel: (1) peak enhancement S n,max normalized to the arterial input function to detect regions of reduced perfusion; (2) time between arterial peak enhancement in the large pulmonary artery and tissue peak enhancement τ to visualize regions with delayed bolus onset; and (3) ratio R = S n,max /τ was calculated to visualize impaired perfusion, irrespectively of whether related to reduced or delayed perfusion. Results: A manual selection of peak perfusion images is not required. Five different types of perfusion can be found: (1) normal perfusion; (2) delayed non-reduced perfusion; (3) reduced non-delayed perfusion; (4) reduced and delayed perfusion; and (5) no perfusion. Types II and IV could not be seen in subtraction images since the temporal information is necessary for this purpose. Conclusions: The analysis strategy in this study allows for a simple and observer-independent visualization and classification of impaired perfusion in dynamic contrast-enhanced pulmonary perfusion MRI by using the temporal information of the datasets.

  9. Analysis of contrast-enhanced ultrasonography using time-intensity curves in prostatic hyperplasia and prostate cancer

    International Nuclear Information System (INIS)

    Fang Junchu; Chen Ming; Sun Huifen

    2008-01-01

    Objective: To study the characters of time-intensity curve of contrast-enhanced ultrasonography in benign prostate hyperplasia (BPH) and prostate cancer. Methods: 2.4 ml Sono Vue were injected as a bolus in 40 patients, 23 patients with BPH and 17 with prostate cancer. High perfusion area in both inner and outer gland were measured with time-intensity curves. Results: It was proved by the time-intensity curves that, in BPH cases, the outer prostate gland presented with mild enhancedment and slow wash-off, while the inner gland presented with moderate enhancedment and fast wash-off. Otherwise, both the inner and outer gland in prostate cancer cases presented with high-intensitive enhancedment and slow wash-off. There was marked difference statistical significance on the up slop, average intensity and area under the time-intensity curves in 90 s and 150 s between the cases of BPH and prostate cancer (P<0.05, P<0.01). Conclusion: Quantitative analysis of high perfusion area in both inner and outer glands is helpful for diagnosing BPH and prostate cancer. (authors)

  10. Apparent Diffusion Coefficient and Dynamic Contrast-Enhanced Magnetic Resonance Imaging in Pancreatic Cancer: Characteristics and Correlation With Histopathologic Parameters.

    Science.gov (United States)

    Ma, Wanling; Li, Na; Zhao, Weiwei; Ren, Jing; Wei, Mengqi; Yang, Yong; Wang, Yingmei; Fu, Xin; Zhang, Zhuoli; Larson, Andrew C; Huan, Yi

    2016-01-01

    To clarify diffusion and perfusion abnormalities and evaluate correlation between apparent diffusion coefficient (ADC), MR perfusion and histopathologic parameters of pancreatic cancer (PC). Eighteen patients with PC underwent diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Parameters of DCE-MRI and ADC of cancer and non-cancerous tissue were compared. Correlation between the rate constant that represents transfer of contrast agent from the arterial blood into the extravascular extracellular space (K, volume of the extravascular extracellular space per unit volume of tissue (Ve), and ADC of PC and histopathologic parameters were analyzed. The rate constant that represents transfer of contrast agent from the extravascular extracellular space into blood plasma, K, tissue volume fraction occupied by vascular space, and ADC of PC were significantly lower than nontumoral pancreases. Ve of PC was significantly higher than that of nontumoral pancreas. Apparent diffusion coefficient and K values of PC were negatively correlated to fibrosis content and fibroblast activation protein staining score. Fibrosis content was positively correlated to Ve. Apparent diffusion coefficient values and parameters of DCE-MRI can differentiate PC from nontumoral pancreases. There are correlations between ADC, K, Ve, and fibrosis content of PC. Fibroblast activation protein staining score of PC is negatively correlated to ADC and K. Apparent diffusion coefficient, K, and Ve may be feasible to predict prognosis of PC.

  11. FDG-PET/contrast-enhanced CT as a post-treatment tool in head and neck squamous cell carcinoma: comparison with FDG-PET/non-contrast-enhanced CT and contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Suenaga, Yuko; Kitajima, Kazuhiro; Sugimura, Kazuro [Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Ishihara, Takeaki; Sasaki, Ryohei [Kobe University Graduate, School of Medicine, Department of Radiology, Division of Radiation Oncology, Kobe (Japan); Otsuki, Naoki; Nibu, Ken-ichi [Kobe University Graduate, School of Medicine, Department of Otolaryngology-Head and Neck Surgery, Kobe (Japan); Minamikawa, Tsutomu [Kobe University Graduate School of Medicine, Department of Oral and Maxillofacial Surgery, Kobe (Japan); Kiyota, Naomi [Kobe University Hospital, Department of Medical Oncology and Hematology, Kobe (Japan)

    2016-04-15

    To evaluate the accuracy of PET/CT using {sup 18}F-fluorodeoxyglucose (FDG) with IV contrast for suspected recurrent head and neck squamous cell carcinoma (HNSCC). One hundred and seventy patients previously treated for HNSCC underwent PET/CT, consisting of non-contrast-enhanced and contrast-enhanced CT, to investigate suspected recurrence. Diagnostic performance of PET/contrast-enhanced CT (PET/ceCT), PET/non-contrast-enhanced CT (PET/ncCT) and contrast-enhanced CT (ceCT) for local or regional recurrence, distant metastasis, overall recurrence and second primary cancer was evaluated. The reference standard included histopathology, treatment change and imaging follow-up. The patient-based areas under the receiver operating characteristic curves (AUC) for ceCT, PET/ncCT and PET/ceCT were 0.82, 0.96 and 0.98 for local recurrence, 0.73, 0.86 and 0.86 for regional recurrence, 0.86, 0.91 and 0.92 for distant metastasis, 0.72, 0.86 and 0.87 for overall recurrence, and 0.86, 0.89 and 0.91 for a second primary cancer. Both PET/ceCT and PET/ncCT statistically showed larger AUC than ceCT for recurrence, and the difference between PET/ceCT and PET/ncCT for local recurrence reached a significant level (p = 0.039). The accuracy of PET/ceCT for diagnosing overall recurrence was high, irrespective of the time interval after the last treatment (83.3-94.1 %). FDG-PET/CT was a more accurate HNSCC restaging tool than ceCT. The added value of ceCT at FDG-PET/CT is minimal. (orig.)

  12. Validation of Contrast Enhanced Cine Steady-State Free Precession and T2-Weigthed CMR for Assessment of Ischemic Myocardial Area- At-Risk

    DEFF Research Database (Denmark)

    Søvsø Szocska Hansen, Esben; Pedersen, Steen Fjord; Pedersen, Steen Bønløkke

    2017-01-01

    -CINE) has recently been used to quantify AAR and validated against myocardial perfusion SPECT. In this study we sought to determine how well T2-STIR and CE-CINE depicts AAR in an experimental porcine model of myocardial ischemia-reperfusion injury using histopathology as the reference for infarct size......Measuring myocardial salvage is important to evaluate the possible cardioprotective effects of adjunctive cardioprotective intervention in patients with myocardial infarction undergoing primary percutaneous intervention. Contrast-enhanced steady-state free precession magnetic resonance imaging (CE...

  13. Quantitative lung perfusion evaluation using Fourier decomposition perfusion MRI.

    Science.gov (United States)

    Kjørstad, Åsmund; Corteville, Dominique M R; Fischer, Andre; Henzler, Thomas; Schmid-Bindert, Gerald; Zöllner, Frank G; Schad, Lothar R

    2014-08-01

    To quantitatively evaluate lung perfusion using Fourier decomposition perfusion MRI. The Fourier decomposition (FD) method is a noninvasive method for assessing ventilation- and perfusion-related information in the lungs, where the perfusion maps in particular have shown promise for clinical use. However, the perfusion maps are nonquantitative and dimensionless, making follow-ups and direct comparisons between patients difficult. We present an approach to obtain physically meaningful and quantifiable perfusion maps using the FD method. The standard FD perfusion images are quantified by comparing the partially blood-filled pixels in the lung parenchyma with the fully blood-filled pixels in the aorta. The percentage of blood in a pixel is then combined with the temporal information, yielding quantitative blood flow values. The values of 10 healthy volunteers are compared with SEEPAGE measurements which have shown high consistency with dynamic contrast enhanced-MRI. All pulmonary blood flow (PBF) values are within the expected range. The two methods are in good agreement (mean difference = 0.2 mL/min/100 mL, mean absolute difference = 11 mL/min/100 mL, mean PBF-FD = 150 mL/min/100 mL, mean PBF-SEEPAGE = 151 mL/min/100 mL). The Bland-Altman plot shows a good spread of values, indicating no systematic bias between the methods. Quantitative lung perfusion can be obtained using the Fourier Decomposition method combined with a small amount of postprocessing. Copyright © 2013 Wiley Periodicals, Inc.

  14. Fibroadenomas of the breast: histopathological/dynamic contrast-enhanced MR correlation

    Energy Technology Data Exchange (ETDEWEB)

    Gilles, R. [Dept. of Radiology, Inst. Gustave Roussy, 94 - Villejuif (France)]|[CIERM, Hopital Bicetre, 94 - Le Kremin-Bicetre (France); Garnier, C. [Dept. of Radiology, Inst. Gustave Roussy, 94 - Villejuif (France)]|[CIERM, Hopital Bicetre, 94 - Le Kremin-Bicetre (France); Meingan, P. [Dept. of Radiology, Inst. Gustave Roussy, 94 - Villejuif (France)]|[CIERM, Hopital Bicetre, 94 - Le Kremin-Bicetre (France); Zemoura, L. [Dept. of Histopathology C, Inst. Gustave Roussy, 94 - Villejuif (France); Lucidarme, O. [Dept. of Radiology, Hopital Salpetriere, 75 - Paris (France); Guinebretiere, J.M. [Dept. of Histopathology C, Inst. Gustave Roussy, 94 - Villejuif (France); Tardivon, A.A. [Dept. of Radiology, Inst. Gustave Roussy, 94 - Villejuif (France)]|[CIERM, Hopital Bicetre, 94 - Le Kremin-Bicetre (France); Arriagada, R. [Breast Cancer Study Group, Inst. Gustave Roussy, 94 - Villejuif, (France)

    1995-12-31

    A total of 22 women with fibroadenomas had preoperative dynamic MR study (T1-weighted images every 47 s after injection of Gd-DOTA). Their age, hormonal status, breast MR studies and histopathological slides were retrospectively reviewed. Eleven pre- (n = 2) or post-menopausal (n = 9) women showed no early contrast enhancement. The absence of early contrast enhancement correlated with hyalin stromal component. Eleven pre- (n = 7) or post-menopausal (n = 4) women showed focal (n = 9) or diffuse (n = 2) early contrast enhancement. Early focal contrast enhancement correlated with myxoid (n = 9), mixed hyalin/myxoid (n = 1) or hyalin (n = 1) fibroadenomas. Early diffuse contrast enhancement of the breast correlated with myxoid (n = 1) or hyalin (n = 1) stromal component associated with proliferative fibrocystic disease of the breast parenchyma. The presence of contrast enhancement correlated with myxoid fibroadenomas, whereas absence of contrast enhancement correlated with hyalin fibroadenomas. As hyalin fibroadenomas occurs in post-menopausal women, the diagnostic accuracy of dynamic MRI may be improved in this age group. (orig.)

  15. Fibroadenomas of the breast: histopathological/dynamic contrast-enhanced MR correlation

    International Nuclear Information System (INIS)

    Gilles, R.; Garnier, C.; Meingan, P.; Zemoura, L.; Lucidarme, O.; Guinebretiere, J.M.; Tardivon, A.A.; Arriagada, R.

    1995-01-01

    A total of 22 women with fibroadenomas had preoperative dynamic MR study (T1-weighted images every 47 s after injection of Gd-DOTA). Their age, hormonal status, breast MR studies and histopathological slides were retrospectively reviewed. Eleven pre- (n = 2) or post-menopausal (n = 9) women showed no early contrast enhancement. The absence of early contrast enhancement correlated with hyalin stromal component. Eleven pre- (n = 7) or post-menopausal (n = 4) women showed focal (n = 9) or diffuse (n = 2) early contrast enhancement. Early focal contrast enhancement correlated with myxoid (n = 9), mixed hyalin/myxoid (n 1) or hyalin (n = 1) fibroadenomas. Early diffuse contrast enhancement of the breast correlated with myxoid (n = 1) or hyalin (n = 1) stromal component associated with proliferative fibrocystic disease of the breast parenchyma. The presence of contrast enhancement correlated with myxoid fibroadenomas, whereas absence of contrast enhancement correlated with hyalin fibroadenomas. As hyalin fibroadenomas occurs in post-menopausal women, the diagnostic accuracy of dynamic MRI may be improved in this age group. (orig.)

  16. Confident Diagnosis of Bronchobiliary Fistula Using Contrast-Enhanced Magnetic Resonance Cholangiography

    Energy Technology Data Exchange (ETDEWEB)

    Karabulut, Nevzat; Cakmak, Vefa; Kiter, Go ksel [Pamukkale University Medical Center, Denizli (Turkmenistan)

    2010-08-15

    We report the utility of contrast-enhanced magnetic resonance cholangiography (MRC) using gadoxetic acid (Gd-EOB-DTPA) in the diagnosis of bronchobiliary fistula associated with liver hydatid cyst. Contrast-enhanced MRC clearly delineated the leakage of contrast agent from the biliary duct and its communication with the bronchial tree. Providing functional information about physiologic or pathologic biliary flow in addition to the display of biliary anatomy, contrast enhanced MRC stands as a robust technique in confidently detecting bronchobiliary fistula and bile leaks

  17. A multi-slice gradient sequence for contrast enhanced MR diagnosis of intracranial tumours

    International Nuclear Information System (INIS)

    Schoerner, W.; Sander, B.; Kornmesser, W.; Laniado, M.; Nakamura, T.; Felix, R.

    1988-01-01

    A multi-slice gradient echo sequence (FLASH) was compared with a conventional spin-echo (SE) technique with regard to its value for contrast enhanced MR diagnosis. In 28 patients with cerebral tumours, SE images (SE 400/30; four images/3.4 minutes) and FLASH images (FLASH 315/14; 15 images/1.4 minutes) were obtained before and after gadolinium DTPA. After gadolinium-DTPA results were comparable for both techniques with respect to contrast enhancement, tumor contrast and delineation. Because of the higher efficiency of the FLASH 315/14 technique, this sequence is the method of choice for contrast enhanced cerebral MR imaging. (orig.) [de

  18. Hepatocellular carcinoma treated with transarterial chemoembolization: Evaluation with parametric contrast-enhanced ultrasonography

    Science.gov (United States)

    Moschouris, Hippocrates; Malagari, Katerina; Marinis, Athanasios; Kornezos, Ioannis; Stamatiou, Konstantinos; Nikas, Georgios; Papadaki, Marina Georgiou; Gkoutzios, Panagiotis

    2012-01-01

    AIM: To evaluate the response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE) using a simplified protocol of parametric contrast-enhanced ultrasound (pCEUS). METHODS: Eighteen patients with HCC (18 target tumors, diameter: 2.8-12 cm) were evaluated before, and 20 d after TACE. The distribution and morphology of TACE-induced necrosis in these tumors precluded accurate evaluation by visual assessment or by simple measurements. For pCEUS, a 4.8 mL bolus of SonoVue (Bracco, Milan, Italy) was intravenously administered and analysis of tumor perfusion during the initial phase of enhancement (0-30 s post injection) was performed with dedicated software (Qontrast, Bracco, Milan, Italy). Time-intensity curves were plotted and three parameters were calculated: peak intensity (PI, in percentage %), time to peak (TTP in seconds, s) and area under the curve during wash-in (AUC-WI, in arbitrary units, a.u). Magnetic resonance imaging was the standard imaging modality for post-treatment evaluation. Changes in tumor size were recorded and response was assessed according to response evaluation criteria in solid tumors criteria. RESULTS: A statistically significant decrease in PI and AUC-WI was observed in the treated tumors post TACE; PIpre: 21.5% ± 8.7% (mean ± SD), PIpost: 12.7% ± 6.7%, P < 0.001, AUC-WI pre: 17493 ± 9563 a.u, AUC-WI post: 9585 ± 5494 a.u, P < 0.001. A slight increase in TTP was noted post TACE, but this was not statistically significant; TTP pre: 13.1 ± 4.3 s, TTP post: 13.6 ± 4.2 s , P = 0.058). The changes in the aforementioned parameters were not accompanied by significant tumor shrinkage. CONCLUSION: pCEUS, even when limited to the study of the arterial phase of tumoral enhancement, can detect and quantify early perfusional changes in HCC post TACE. PMID:22937217

  19. Perfusion and diffusion MR imaging in enhancing malignant cerebral tumors

    International Nuclear Information System (INIS)

    Calli, Cem; Kitis, Omer; Yunten, Nilgun; Yurtseven, Taskin; Islekel, Sertac; Akalin, Taner

    2006-01-01

    Objective: Common contrast-enhancing malignant tumors of the brain are glioblastoma multiforme (GBMs), anaplastic astrocytomas (AAs), metastases, and lymphomas, all of which have sometimes similar conventional MRI findings. Our aim was to evaluate the role of perfusion MR imaging (PWI) and diffusion-weighted imaging (DWI) in the differentiation of these contrast-enhancing malignant cerebral tumors. Materials and methods: Forty-eight patients with contrast-enhancing and histologically proven brain tumors, 14 AAs, 17 GBMs, nine metastases, and eight lymphomas, were included in the study. All patients have undergone routine MR examination where DWI and PWI were performed in the same session. DWI was performed with b values of 0, 500, and 1000 mm 2 /s. Minimum ADC values (ADC min ) of each tumor was later calculated from ADC map images. PWI was applied using dynamic susceptibility contrast technique and maximum relative cerebral blood volume (rCBV max ) was calculated from each tumor, given in ratio with contralateral normal white matter. Comparisons of ADC min and rCBV max values with the histological types of the enhancing tumors were made with a one-way analysis of variance and Bonferroni test. A P value less than 0.05 indicated a statistically significant difference. Results: The ADC min values (mean ± S.D.) in GBMs, AAs, lymphomas, and metastases were 0.79 ± 0.21 (x10 -3 mm 2 /s), 0.75 ± 0.21 (x10 -3 mm 2 /s), 0.51 ± 0.09 (x10 -3 mm 2 /s), and 0.68 ± 0.11 (x10 -3 mm 2 /s), respectively. The difference in ADC min values were statistically significant between lymphomas and GBMs (P max ratio (mean ± S.D.) in GBMs were 6.33 ± 2.03, whereas it was 3.66 ± 1.79 in AAs, 2.33 ± 0.68 in lymphomas, and 4.45 ± 1.87 in metastases. These values were statistically different between GBMs and AAs (P min and rCBV max calculations, may aid routine MR imaging in the differentiation of common cerebral contrast-enhancing malignant tumors

  20. Pretreatment Evaluation of Microcirculation by Dynamic Contrast-Enhanced Magnetic Resonance Imaging Predicts Survival in Primary Rectal Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    DeVries, Alexander Friedrich [Department of Radio-Oncology, Academic Teaching Hospital Feldkirch, Feldkirch (Austria); Piringer, Gudrun, E-mail: gudrun.piringer@hotmail.com [Department of Oncology, Wels-Grieskirchen Medical Hospital, Wels (Austria); Kremser, Christian; Judmaier, Werner [Department of Radiology, Innsbruck Medical University, Innsbruck (Austria); Saely, Christoph Hubert [Department of Medicine and Cardiology, Academic Teaching Hospital Feldkirch, Feldkirch (Austria); Lukas, Peter [Department of Radio-Oncology, Innsbruck Medical University, Innsbruck (Austria); Öfner, Dietmar [Department of Surgery, Paracelsus Medical University, Salzburg (Austria)

    2014-12-01

    Purpose: To investigate the prognostic value of the perfusion index (PI), a microcirculatory parameter estimated from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), which integrates information on both flow and permeability, to predict overall survival and disease-free survival in patients with primary rectal cancer. Methods and Materials: A total of 83 patients with stage cT3 rectal cancer requiring neoadjuvant chemoradiation were investigated with DCE-MRI before start of therapy. Contrast-enhanced dynamic T{sub 1} mapping was obtained, and a simple data analysis strategy based on the calculation of the maximum slope of the tissue concentration–time curve divided by the maximum of the arterial input function was used as a measure of tumor microcirculation (PI), which integrates information on both flow and permeability. Results: In 39 patients (47.0%), T downstaging (ypT0-2) was observed. During a mean (±SD) follow-up period of 71 ± 29 months, 58 patients (69.9%) survived, and disease-free survival was achieved in 45 patients (54.2%). The mean PI (PImean) averaged over the group of nonresponders was significantly higher than for responders. Additionally, higher PImean in age- and gender-adjusted analyses was strongly predictive of therapy nonresponse. Most importantly, PImean strongly and significantly predicted disease-free survival (unadjusted hazard ratio [HR], 1.85 [ 95% confidence interval, 1.35-2.54; P<.001)]; HR adjusted for age and sex, 1.81 [1.30-2.51]; P<.001) as well as overall survival (unadjusted HR 1.42 [1.02-1.99], P=.040; HR adjusted for age and sex, 1.43 [1.03-1.98]; P=.034). Conclusions: This analysis identifies PImean as a novel biomarker that is predictive for therapy response, disease-free survival, and overall survival in patients with primary locally advanced rectal cancer.

  1. THE EXPERIENCE OF USING ULTRASOUND WITH CONTRAST ENHANCEMENT IN THE DIAGNOSIS OF CERVICAL CANCER

    Directory of Open Access Journals (Sweden)

    M. A. Chekalova

    2017-01-01

    Full Text Available The purpose of the study was to evaluate the value of contrast-enhanced ultrasound in detecting local spread, regional and distant metastases from cervical cancer. Materials and methods. The findings of contrast-enhanced ultrasound examination of 4 cervical cancer patients (IB1–IVB treated at N.N. Blokhin Russian Cancer Research Center from September to October 2016 were evaluated. The HI VISION Ascendus device was used. Ultrasound patterns in different phases of contrast-enhanced accumulation and excretion were analyzed. Results. Our first experience in using contrast-enhanced ultrasound in the detection of local spread, regional and distant metastases from cervical cancer allowed us to study the structure of the tumor and its spread in greater detail. Conclusion. A small number of observations do not yet allow us to draw serious conclusions about the capabilities of this modern technology. 

  2. Vessel diameter measurements in gadolinium contrast-enhanced three-dimensional MRA of peripheral arteries

    NARCIS (Netherlands)

    Westenberg, J.J.M.; Geest, van der R.J.; Wasser, M.N.J.M.; Linden, van der E.L.; Walsum, van T.; Assen, van H.C.; Roos, de A.; Vanderschoot, J.; Reiber, J.H.C.

    2000-01-01

    In this study, the possibilities for quantification of vessel diameters of peripheral arteries in gadolinium contrast-enhanced magnetic resonance angiography (Gd CE MRA) were evaluated. Absolute vessel diameter measurements were assessed objectively and semi-automatically in maximum intensity

  3. Value of the Gd-DTPA contrast enhanced MR in patients with failed back surgery syndrome

    International Nuclear Information System (INIS)

    Paprzycki, W.; Gradzki, J.; Sosnowski, P.; Stajgis, M.

    1994-01-01

    Gd-DTPA contrast - enhanced MR enables differentiation between postoperative scar and recurrent prolapse of nucleus pulposus (RPNP). Pre- and post-contrast MR studies in 40 patients with failed back surgery syndrome, previously treated surgically on 54 intervertebral levels, were evaluated. Presence of RPNP was confirmed on 4, postoperative scars on 35 and both condition on 15 invertebral levels. Correct interpretation of pathologic changes on 15 invertebral levels (28%) was only possible after contrast enhancement. Contrast enhancement of scar excluded the diagnosis of coexistence of RPNP and scar, based on pre-contrast MR studies. MR with Gd-DTPA contrast enhancement is the best diagnostic method in patients with failed back surgery syndrome (author)

  4. Biliary complications following orthotopic liver transplantation: May contrast-enhanced MR Cholangiography provide additional information?

    Directory of Open Access Journals (Sweden)

    Piero Boraschi

    2016-01-01

    Conclusions: Contrast-enhanced T1-weighted MR Cholangiography may improve the level of diagnostic confidence provided by conventional T2-weighted MR Cholangiography in the evaluation of biliary complications after orthotopic liver transplantation.

  5. Improvement of observer performance during fluoroscopy by local adaptive contrast enhancement

    International Nuclear Information System (INIS)

    Gould, R.G.; Demas, B.E.; Maroney, T.P.

    1988-01-01

    The ability of a video processor (FluoroVision FV-1), which performs two-dimensional locally adaptive contrast enhancement, to improve the detection of a low-contrast object was evaluated by means of receiver operating characteristic (ROC) curves. Three independent observers viewed a videotape of 50 fluoroscopic images of a varied background, in which a test object was present in 25. Each observer viewed the tape under four conditions: (1) no processing, (2) temporal noise reduction (gaussian weighted time averaging, (3) contrast enhancement, and (4) both noise reduction and contrast enhancement. The results were that detection was significantly improved by the locally adaptive contrast enhancement. Noise reduction did not significantly improve performance, probably because washer detection was limited by background contrast variations as well as noise and because only a small amount of noise reduction was used. The authors conclude that the processing device is potentially valuable in improving the quality of clinical fluoroscopic images

  6. MR imaging of spine and spinal canal neoplasms: value of Gd-DTPA contrast enhancement

    International Nuclear Information System (INIS)

    Paprzycki, W.; Gradzki, J.; Sosnowski, P.; Stajgis, M.

    1994-01-01

    Value of Gadolinium-DTPA contrast enhancement in diagnosis of neoplastic diseases of spinal canal was estimated on the basis of retrospective analysis of MR examinations performed in 75 patients. The analyzed material consisted of 15 cases of intramedullary tumors (group 1.), 38 of subdural extramedullary (group 2.) and 22 extradural ones (group 3.). Contrast enhanced MR contributed significant information to the final diagnosis in all groups. The utmost significance of Gd-DTPA contrast enhancement was ascertained in group 1. Authors conclude that contrast enhancement with Gd-DTPA is indispensable in all these cases of spinal canal neoplasms, where non-contrast MR did not reveal pathologic changes in optimal manner. (author)

  7. Local Contrast Enhancement Using Intuitionistic Fuzzy Sets Optimized By Artificial Bee Colony Algorithm

    Directory of Open Access Journals (Sweden)

    Daniel M. Wonohadidjojo

    2017-03-01

    was applied. The results of local contrast enhancement using both methods were compared with the results using histogram equalization method. The tests were conducted using two MDCK cell images. The results of local contrast enhancement using both methods were evaluated by observing the enhanced images and IEM values. The results show that the methods outperform the histogram equalization method. Furthermore, the method using IFSABC is better than the IFS method.

  8. The role of contrast-enhanced ultrasonography in image-guided liver ablations

    International Nuclear Information System (INIS)

    Pescatori, Lorenzo Carlo; Sconfienza, Luca Maria; Mauri, Giovanni

    2016-01-01

    We read with great interest the paper by Kim et al. entitled “Local ablation therapy with contrast enhanced ultrasonography for hepatocellular carcinoma: a practical review,” recently published in Ultrasonography. We think that contrast-enhanced ultrasonography (CEUS), together with the development of reliable navigation systems, is likely to represent one of the most important advances in image-guided ablations in recent years. Thus, we offer some considerations on the topic

  9. Intravenous contrast-enhanced sonography in children and adolescents – a single center experience

    Directory of Open Access Journals (Sweden)

    Martin Stenzel

    2013-06-01

    Full Text Available Compared to adult patients, ultrasonography in children and adolescents is much more common, due to lack of ionizing radiation, and its wide availability. With the introduction of contrast-media for use in ultrasonography, one major drawback of the method could be overcome. In Europe, SonoVue® is the only widely available agent, which due to improved stability makes it possible to image normal and diseased tissue perfusion and vascularization with high accuracy. Inability to hold the breath and voluntary body movement of the patient is less of an obstacle compared to color Doppler techniques and makes the method very attractive for use in children, which, depending on age, may not be very cooperative. Use of intravenous contrast-medium in minors is currently very limited for several reasons: availability, lack of recommendation in national and international guidelines, and lack of official licensing. The article will touch medical indications, technique, safety considerations, and perspective of intravenous use of contrast-media in children and adolescents, including data from a 6-year period in 37 patients. Purpose: The purpose of the study was to collect data on ultrasonographic examinations, expanded by intravenous administration of the contrast agent SonoVue® in children and adolescents. Besides assessing diagnostic yield, data on adverse medication effects was collected. Materials and methods: The study includes contrast-enhanced ultrasound examinations in 37 children at a single institution. Indications for the examinations were tumor lesions, infections, traumatic organ injuries, and parenchymal organ ischemia. Parents of the patients and adolescent patients were informed about the off-label use of the contrast agent. Thirty-nine examinations were performed, the average age of the patient was 11.1 years (range 1 7/ 12 to 17 11/ 12 years. Results: All of the examinations yielded additional diagnostic value, always expanding results

  10. Real-time 3-dimensional contrast-enhanced ultrasound in detecting hemorrhage of blunt renal trauma.

    Science.gov (United States)

    Xu, Rui-Xue; Li, Ye-Kuo; Li, Ting; Wang, Sha-Sha; Yuan, Gui-Zhong; Zhou, Qun-Fang; Zheng, Hai-Rong; Yan, Fei

    2013-10-01

    The objective of this study is to evaluate the diagnostic value of real-time 3-dimensional contrast-enhanced ultrasound in the hemorrhage of blunt renal trauma. Eighteen healthy New Zealand white rabbits were randomly divided into 3 groups. Blunt renal trauma was performed on each group by using minitype striker. Ultrasonography, color Doppler flow imaging, and contrast-enhanced 2-dimensional and real-time 3-dimensional ultrasound were applied before and after the strike. The time to shock and blood pressure were subjected to statistical analysis. Then, a comparative study of ultrasound and pathology was carried out. All the struck kidneys were traumatic. In the ultrasonography, free fluid was found under the renal capsule. In the color Doppler flow imaging, active hemorrhage was not identified. In 2-dimensional contrast-enhanced ultrasound, active hemorrhage of the damaged kidney was characterized. Real-time 3-dimensional contrast-enhanced ultrasound showed a real-time and stereoscopic ongoing bleeding of the injured kidney. The wider the hemorrhage area in 4-dimensional contrast-enhanced ultrasound was, the faster the blood pressure decreased. Real-time 3-dimensional contrast-enhanced ultrasound is a promising noninvasive tool for stereoscopically and vividly detecting ongoing hemorrhage of blunt renal trauma in real time. © 2013.

  11. Dynamic contrast-enhanced magnetic resonance imaging of the wrist in children with juvenile idiopathic arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Nusman, Charlotte M. [Emma Children' s Hospital, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Academic Medical Center, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Lavini, Cristina; Hemke, Robert; Caan, Matthan W.A.; Maas, Mario [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Schonenberg-Meinema, Dieneke; Berg, J.M. van den; Kuijpers, Taco W. [Emma Children' s Hospital, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Academic Medical Center, Amsterdam (Netherlands); Dolman, Koert M. [Sint Lucas Andreas Hospital, Department of Pediatrics, Amsterdam (Netherlands); Reade Institute location Jan van Breemen, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Rossum, Marion A.J. van [Reade Institute location Jan van Breemen, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Emma Children' s Hospital, Department of Pediatrics, Academic Medical Center, Amsterdam (Netherlands)

    2017-02-15

    Dynamic contrast-enhanced MRI provides information on the heterogeneity of the synovium, the primary target of disease in children with juvenile idiopathic arthritis (JIA). To evaluate the feasibility of dynamic contrast-enhanced MRI in the wrist of children with JIA using conventional descriptive measures and time-intensity-curve shape analysis. To explore the association between enhancement characteristics and clinical disease status. Thirty-two children with JIA and wrist involvement underwent dynamic contrast-enhanced MRI with movement-registration and were classified using validated criteria as clinically active (n = 27) or inactive (n = 5). Outcome measures included descriptive parameters and the classification into time-intensity-curve shapes, which represent the patterns of signal intensity change over time. Differences in dynamic contrast-enhanced MRI outcome measures between clinically active and clinically inactive disease were analyzed and correlation with the Juvenile Arthritis Disease Activity Score was determined. Comprehensive evaluation of disease status was technically feasible and the quality of the dynamic dataset was improved by movement registration. The conventional descriptive measure maximum enhancement differed significantly between clinically active and inactive disease (P = 0.019), whereas time-intensity-curve shape analysis showed no differences. Juvenile Arthritis Disease Activity Score correlated moderately with enhancing volume (P = 0.484). Dynamic contrast-enhanced MRI is a promising biomarker for evaluating disease status in children with JIA and wrist involvement. Conventional descriptive dynamic contrast-enhanced MRI measures are better associated with clinically active disease than time-intensity-curve shape analysis. (orig.)

  12. Gray-scale contrast-enhanced utrasonography in detecting sentinel lymph nodes: An animal study

    International Nuclear Information System (INIS)

    Wang Yuexiang; Cheng Zhigang; Li Junlai; Tang Jie

    2010-01-01

    Objective: To investigate the usefulness of gray-scale contrast-enhanced ultrasonography for detecting sentinel lymph nodes. Methods: Contrast-enhanced ultrasonography was performed in five normal dogs (four female and one male) after subcutaneous administration of a sonographic contrast agent (Sonovue, Bracco, Milan, Italy). Four distinct regions in each animal were examined. After contrast-enhanced ultrasonography, 0.8 ml of blue dye was injected into the same location as Sonovue and the sentinel lymph nodes were detected by surgical dissection. The findings of contrast-enhanced ultrasonography were compared with those of the blue dye. Results: Twenty-one sentinel lymph nodes were detected by contrast-enhanced ultrasonography while 23 were identified by blue dye with surgical dissection. Compared with the blue dye, the detection rate of enhanced ultrasonography for the sentinel lymph nodes is 91.3% (21/23). Two patterns of enhancement in the sentinel lymph nodes were observed: complete enhancement (5 sentinel lymph nodes) and partial enhancement (16 sentinel lymph nodes). The lymphatic channels were demonstrated as hyperechoic linear structures leading from the injection site and could be readily followed to their sentinel lymph nodes. Histopathologic examination showed proliferation of lymphatic follicles or lymphatic sinus in partial enhanced sentinel lymph nodes while normal lymphatic tissue was demonstrated in completely enhanced sentinel lymph nodes. Conclusions: Sonovue combined with gray-scale contrast-enhanced ultrasonography may provide a feasible method for detecting sentinel lymph nodes.

  13. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    International Nuclear Information System (INIS)

    Nakamura, T.; Naganawa, S.; Fukatsu, H.; Sakurai, Y.; Ishigaki, T.; Aoki, I.; Ninomiya, A.; Nakashima, T.

    2003-01-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  14. Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T; Naganawa, S; Fukatsu, H; Sakurai, Y; Ishigaki, T [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, 466-8550, Shouwa-ku, Nagoya (Japan); Aoki, I; Ninomiya, A [Medical Systems Company, Toshiba Corporation, Nasu Operations, Otawara-shi, Tochigi (Japan); Nakashima, T [Department of Otorhinolaryngology, Nagoya University School of Medicine, Shouwa-ku, Nagoya (Japan)

    2003-09-01

    There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion. (orig.)

  15. Radiofrequency ablation of liver cancer: early evaluation of therapeutic response with contrast-enhanced ultrasonography

    International Nuclear Information System (INIS)

    Choi, Dong Gil; Lim, Hyo K.; Lee, Won Jae; Kim, Seung Hoon; Kim, Min Ju; Kim, Seung Kwon; Jang, Kyung Mi; Lee, Ji Yeon; Lim, Jae Hoon

    2004-01-01

    The early assessment of the therapeutic response after percutaneous radiofrequency (RF) ablation is important, in order to correctly decide whether further treatment is necessary. The residual unablated tumor is usually depicted on contrast-enhanced multiphase helical computed tomography (CT) as a focal enhancing structure during the arterial and portal venous phases. Contrast-enhanced color Doppler and power Doppler ultrasonography (US) have also been used to detect residual tumors. Contrast-enhanced gray-scale US, using a harmonic technology which has recently been introduced, allows for the detection of residual tumors after ablation, without any of the blooming or motion artifacts usually seen on contrast-enhanced color or power Doppler US. Based on our experience and reports in the literature, we consider that contrast-enhanced gray-scale harmonic US constitutes a reliable alternative to contrast-enhanced multiphase CT for the early evaluation of the therapeutic response to RF ablation for liver cancer. This technique was also useful in targeting any residual unablated tumors encountered during additional ablation

  16. Modifications in Dynamic Contrast-Enhanced Magnetic Resonance Imaging Parameters After α-Particle-Emitting {sup 227}Th-trastuzumab Therapy of HER2-Expressing Ovarian Cancer Xenografts

    Energy Technology Data Exchange (ETDEWEB)

    Heyerdahl, Helen, E-mail: Helen.Heyerdahl@rr-research.no [Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo (Norway); Røe, Kathrine [Department of Oncology, Division of Medicine, Akershus University Hospital, Lørenskog (Norway); Brevik, Ellen Mengshoel [Department of Research and Development, Algeta ASA, Oslo (Norway); Dahle, Jostein [Nordic Nanovector AS, Oslo (Norway)

    2013-09-01

    Purpose: The purpose of this study was to investigate the effect of α-particle-emitting {sup 227}Th-trastuzumab radioimmunotherapy on tumor vasculature to increase the knowledge about the mechanisms of action of {sup 227}Th-trastuzumab. Methods and Materials: Human HER2-expressing SKOV-3 ovarian cancer xenografts were grown bilaterally in athymic nude mice. Mice with tumor volumes 253 ± 36 mm{sup 3} (mean ± SEM) were treated with a single injection of either {sup 227}Th-trastuzumab at a dose of 1000 kBq/kg body weight (treated group, n=14 tumors) or 0.9% NaCl (control group, n=10 tumors). Dynamic T1-weighted contrast-enhanced magnetic resonance imaging (DCEMRI) was used to study the effect of {sup 227}Th-trastuzumab on tumor vasculature. DCEMRI was performed before treatment and 1, 2, and 3 weeks after therapy. Tumor contrast-enhancement curves were extracted voxel by voxel and fitted to the Brix pharmacokinetic model. Pharmacokinetic parameters for the tumors that underwent radioimmunotherapy were compared with the corresponding parameters of control tumors. Results: Significant increases of k{sub ep}, the rate constant of diffusion from the extravascular extracellular space to the plasma (P<.05), and k{sub el,} the rate of clearance of contrast agent from the plasma (P<.01), were seen in the radioimmunotherapy group 2 and 3 weeks after injection, compared with the control group. The product of k{sub ep} and the amplitude parameter A, associated with increased vessel permeability and perfusion, was also significantly increased in the radioimmunotherapy group 2 and 3 weeks after injection (P<.01). Conclusions: Pharmacokinetic modeling of MRI contrast-enhancement curves evidenced significant alterations in parameters associated with increased tumor vessel permeability and tumor perfusion after {sup 227}Th-trastuzumab treatment of HER2-expressing ovarian cancer xenografts.

  17. Combined diffusion-weighted and dynamic contrast-enhanced imaging of patients with acute osteoporotic vertebral fractures

    International Nuclear Information System (INIS)

    Biffar, Andreas; Sourbron, Steven; Dietrich, Olaf; Schmidt, Gerwin; Ingrisch, Michael; Reiser, Maximilian F.; Baur-Melnyk, Andrea

    2010-01-01

    Objectives: To evaluate the potential and to analyze parameter correlations of combined quantitative diffusion-weighted MRI (DWI) and high-temporal-resolution dynamic contrast-enhanced MRI (DCE-MRI) in vertebral bone marrow (vBM) of patients with osteoporosis and acute vertebral compression fractures, providing additional information for a better understanding of the physiological background of parameter changes. Materials and methods: 20 patients with acute osteoporotic fractures were examined with DWI and DCE-MRI at 1.5 T. DCE-MRI was performed with a 2D saturation-recovery turbo-FLASH sequence, acquiring 300 dynamics with a temporal resolution of 1 s. For DWI measurements, a DW HASTE sequence with b-values from 100 to 600 s/mm 2 was applied. In each patient, ROIs were drawn manually in the fractures and in normal appearing vertebrae. For DCE-MRI, the concentration-time curves of these ROIs were analyzed using a two-compartment tracer-kinetic model in the lesions, providing separate estimates of perfusion and permeability, and a one-compartment model in normal vBM, providing only a mixed representation of perfusion and permeability in terms of a mixed flow parameter K trans and the extracellular volume (ECV). In the case of DWI, attenuation curves were fitted to a monoexponential decay model to determine the apparent diffusion coefficient (ADC). Results: Mean perfusion parameters and ADCs were significantly (p trans : 7.81 mL/100 mL/min vs. 14.61 mL/100 mL/min, ECV: 52.84 mL/100 mL vs. 4.61 mL/100 mL, ADC: 1.71 x 10 -3 mm 2 /s vs. 0.57 x 10 -3 mm 2 /s). ADCs showed a significant correlation with the ECV. Conclusion: The quantitative analysis of DWI and DCE-MRI could distinguish osteoporotic fractures from normal appearing vertebrae. A significant correlation found between ECV and ADCs might be able to explain the cause for the increased diffusivity in osteoporotic fractures. Since the other perfusion parameters do not correlate with the ADC, they provide

  18. Three-dimensional gradient echo versus spin echo sequence in contrast-enhanced imaging of the pituitary gland at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Kakite, Suguru, E-mail: sugkaki@med.tottori-u.ac.jp [Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, 36-1, Nishicho, Yonago 683-8503 (Japan); Fujii, Shinya [Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, 36-1, Nishicho, Yonago 683-8503 (Japan); Kurosaki, Masamichi [Department of Neurosurgery, Faculty of Medicine, Tottori University, 36-1, Nishicho, Yonago 683-8503 (Japan); Kanasaki, Yoshiko; Matsusue, Eiji; Kaminou, Toshio; Ogawa, Toshihide [Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, 36-1, Nishicho, Yonago 683-8503 (Japan)

    2011-07-15

    Introduction: To clarify whether a three-dimensional-gradient echo (3D-GRE) or spin echo (SE) sequence is more useful for evaluating sellar lesions on contrast-enhanced T1-weighted MR imaging at 3.0 Tesla (T). Methods: We retrospectively assessed contrast-enhanced T1-weighted images using 3D-GRE and SE sequences at 3.0 T obtained from 33 consecutive patients with clinically suspected sellar lesions. Two experienced neuroradiologists evaluated the images qualitatively in terms of the following criteria: boundary edge of the cavernous sinus and pituitary gland, border of sellar lesions, delineation of the optic nerve and cranial nerves within the cavernous sinus, susceptibility and flow artifacts, and overall image quality. Results: At 3.0 T, 3D-GRE provided significantly better images than the SE sequence in terms of the border of sellar lesions, delineation of cranial nerves, and overall image quality; there was no significant difference regarding the boundary edge of the cavernous sinus and pituitary gland. In addition, the 3D-GRE sequence showed fewer pulsation artifacts but more susceptibility artifacts. Conclusion: Our results indicate that 3D-GRE is the more suitable sequence for evaluating sellar lesions on contrast-enhanced T1-weighted imaging at 3.0 T.

  19. Changes in the micro-circulation of skeletal muscle due to varied isometric exercise assessed by contrast-enhanced ultrasound

    International Nuclear Information System (INIS)

    Krix, Martin; Weber, Marc-Andre; Kauczor, Hans-Ulrich; Delorme, Stefan; Krakowski-Roosen, Holger

    2010-01-01

    Purpose: To quantitatively assess local muscle micro-circulation with real-time contrast-enhanced ultrasound (CEUS) during different exercises and compare the results with performed muscle work and global blood flow. Materials and methods: Sixteen low mechanical index CEUS examinations of the right lower leg flexors of healthy volunteers were performed using a continuous infusion of SonoVue (4.8 mL/300 s). Several muscle perfusion parameters were extracted from derived CEUS signal intensity time curves during different isometric exercises (10-50% of maximum individual strength for 20-30 s) and then correlated with the performed muscle work or force, and the whole lower leg blood flow which we measured simultaneously by venous occlusion plethysmography (VOP). Results: The shapes of the CEUS curve during and after exercise differed individually depending on the performed muscle work. The maximum blood volume MAX was observed only after exercise cessation and was significantly correlated with the performed muscle force (r = 0.77, p < 0.0001). The blood volume over exercise time was inversely correlated with the spent muscle work (r = -0.60, p = 0.006). CEUS and VOP measurements correlated only at rest and after the exercise. During exercise, mean CEUS local blood volume decreased (from 3.48 to 2.19 (∼mL)), while mean VOP global blood flow increased (mean, from 3.96 to 7.71 mL/100 mg/min). Conclusion: Real-time low-MI CEUS provides complementary information about the local muscle micro-circulation compared to established blood flow measures. CEUS may be used for a better understanding of muscle perfusion physiology and in the diagnosis of micro-circulation alterations such as in peripheral arterial occlusive disease or diabetic angiopathy.

  20. Contrast-enhanced magnetic resonance angiography of persistent fifth aortic arch in children

    International Nuclear Information System (INIS)

    Zhong, Yumin; Zhu, Ming; Sun, Aimin; Li, Yuhua; Jaffe, Richard B.; Gao, Wei

    2007-01-01

    Cine angiography and echocardiography have been utilized to diagnose congenital aortic arch anomalies. However, the visualization of great vessels by echocardiography is limited, while cine angiography requires cardiac catheterization with ionizing radiation. Contrast-enhanced magnetic resonance angiography (MRA) is a noninvasive modality suitable for visualization of congenital aortic arch anomalies. To evaluate the utility of contrast-enhanced MRA in the diagnosis of persistent fifth aortic arch, a rare congenital aortic arch anomaly, and to compare the diagnostic accuracy of MRA with that of echocardiography and cine angiography. In four pediatric patients, contrast-enhanced MRA studies were performed for diagnosing persistent fifth aortic arch. The findings of MRA were compared with echocardiographic findings and confirmed by cine angiography and operation. Transthoracic surface echocardiography noted an aberrant vessel arising from the ascending aorta in two of four patients; the etiology of this vessel was uncertain. In the other two patients a diagnosis of coarctation was made. Of the four patients, only one was diagnosed with interruption of the aortic arch. Contrast-enhanced MRA clarified uncertain echocardiographic findings, enabling the correct diagnosis of persistent fifth aortic arch with fourth aortic arch interruption in all four patients. Contrast-enhanced MRA is a safe, accurate, and fast imaging technique for the evaluation of persistent fifth aortic arch and may obviate the need for conventional cine angiography. Cardiac catheterization may be reserved for some types of complicated congenital heart disease and for obtaining hemodynamic information. (orig.)

  1. Analysis of peritumoral edema and contrast enhancement by computerized axial tomography

    International Nuclear Information System (INIS)

    Oi, Shizuo; Szper, I.; Wetzel, N.; Kim, Kwang-S.

    1980-01-01

    For the purpose of treating brain tumors satisfactorily with steroids, CT findings of brain tumors were analyzed, and pathogenesis of peritumoral edema and supposed effects of steroids were investigated. The degree of peritumoral edema and contrast enhancement and their relationship were analyzed in total 201 patients with brain tumors (gliomas, meningiomas, and metastatic brain tumors). As a result, significant peritumoral edema was recognized in 59% of patients with metastatic brain tumors, 46% of patients with glioma, and 34% of patients with meningioma. As a rule, there was a relationship between peritumoral edema and malignancy or localization of braiin tumors. Severe peritumoral edema was observed in malignant supratentorial tumors (over 60%), but peritumoral edema which was found in infratentorial tumors benign gliomas was mild. The degree of contrast enhancement differed according to tumors, and there was not always a relationship between the degree of contrast enhancement and malignancy or localization of brain tumors. CT findings of brain tumors after the administration of steroids showed decrease in the degree of contrast enhancement. Judging from the effect of steroids to inhibit increased vascular permeability associated with brain edema, like CT findings of peritumoral edema, the degree of contrast enhancement which probably expressed vascularity or vascular permeability seemed to be important in deciding the indications for steroid administration. (Tsunoda, M.)

  2. The role of contrast-enhanced digital subtraction MRI in the diagnosis of vertebral metastasic tumors

    International Nuclear Information System (INIS)

    Xiao Yeyu; Yang Jun; Qi Weili; Liu Qize; Hong Bikai; Wu Renhua

    2008-01-01

    Objective: To evaluate the contrast-enhanced digital subtraction MRI in the diagnosis of vertebral metastasic tumors. Methods 66 vertebral metastasic tumors in 43 patients were examined with conventional MRI (T 1 WI, STIR and Contrast-enhanced T 1 WI) and contrast-enhanced digital subtraction MR imaging. All lesions were histologically proved. The quantity and characteristic imaging signs (including spiculation, bull eye sign and irregular edge) of lesions were detected separately by different sequences. K independent samples test was used. Results: The detection rates of 35 vertebral metastasic tumors with vertebral morphological changes were same in all MR sequences. But in the other 31 lesions without vertebral morphological changes, the detection rates were different and STIR was the highest in all sequences. Contrast-enhanced digital subtraction MRI was more sensitive than all the conventional MR sequences in finding characteristic imaging signs with statistically significant differences. Conclusion: Contrast enhanced subtraction MRI is an useful and convenient technique which has great value in finding vertebral metastasic tumors and depicting the characteristic imaging signs. (authors)

  3. Contrast-enhanced power Doppler US of hepatocellular carcinomas: Quantitative analysis

    International Nuclear Information System (INIS)

    Kim, Ah Young; Choi, Byung Ihn; Kim, Tae Kyoung; Lee, Kyoung Ho; Han, Joon Koo

    1999-01-01

    To determine peak time and duration of contrast enhancement of nodular hepatocellular carcinoma (HCC) on contrast-enhancement power Doppler ultrasound (US) with Levovist by quantitative analysis. Twenty eight patients with nodular HCC were prospectively evaluated with power Doppler US by one examiner. Serial images were obtained before and after injection of 300 mg/mL US contrast agent (SH U 508 A, Levovist, Schering) with the injection rate of 0.2 mL/sec. Power Doppler signals on obtained digital images were quantified using 'Ultrasound Imaging Tool Version 1.0' (Seoul, Korea). The grade, peak time and duration of contrast enhancement of the tumors were analyzed. For nodular HCCs, mean peak enhancement time was 60 seconds after injection of Levovist (mean enhanced area 41.6 ± 28.6 %). These tumoral enhancement decreased from 90 seconds and returned to near baseline state at 5 minutes after injection of Levovist. Maximum enhanced areas (%) were variable at a range of 8-98.5% and mean maximum enhanced area was 46.4 ± 28.6%. On contrast-enhanced power Doppler US with Levovist, nodular HCCs showed peak contrast enhancement (41.6± 28.6) at 60 seconds after injection of contrast agent. This tumoral enhancement nearly disappeared at 5 minutes after injection of contrast agent.

  4. The analysis of the contrast enhanced lesions on cerebro-vascular diseases

    International Nuclear Information System (INIS)

    Terada, Tomoaki; Nishiguchi, Takashi; Hyoutani, Genhachi; Miyamoto, Kazuki; Komai, Norihiko

    1989-01-01

    The contrast enhancement of cerebro-vascular diseases on CT is thought to be due to the increase of the cerebral blood volume (CBV) and/or the disruption of the blood brain barrier (BBB). However, it is difficult to differentiate these two conditions only by contrast enhanced CT. We employed dynamic CT (DCT) to analyse these lesions with respect to the patterns of time-density curve and peak height (PH) of the curve upon the theoretical basis that flattening of the latter part of the time-density curve reflected the degree of BBB disruption and PH reflected the CBV. In all cases of hypertensive intracerebral hemorrhage (11 cases), the contrast enhanced lesion around the hematoma showed marked BBB disruption according to the results of DCT. In 11 cases of cerebral infarction, patterns of BBB disruption and CBV varied at the contrast enhanced lesions according to the result of DCT. However, all contrast enhanced lesions with increased PH were associated with hemorrhagic infarction. Thus, the precise analysis of DCT provides appropriate therapeutic schedules by predicting the occurrence of hemorrhagic infarction. (author)

  5. Diagnosis of hepatic steatosis by contrast-enhanced abdominal computed tomography

    Directory of Open Access Journals (Sweden)

    Rodrigo da Fonseca Monjardim

    2013-06-01

    Full Text Available Objective To evaluate the diagnostic capacity of abdominal computed tomography in the assessment of hepatic steatosis using the portal phase with a simplified calculation method as compared with the non-contrast-enhanced phase. Materials and Methods In the present study, 150 patients were retrospectively evaluated by means of non-contrast-enhanced and contrast-enhanced computed tomography. One hundred patients had hepatic steatosis and 50 were control subjects. For the diagnosis of hepatic steatosis in the portal phase, the authors considered a result of < 104 HU calculated by the formula [L - 0.3 × (0.75 × P + 0.25 × A] / 0.7, where L, P and A represent the attenuation of the liver, of the main portal vein and abdominal aorta, respectively. Sensitivity, specificity, positive and negative predictive values were calculated, using non-contrast-enhanced computed tomography as the reference standard. Results The simplified calculation method with portal phase for the diagnosis of hepatic steatosis showed 100% sensitivity, 36% specificity, negative predictive value of 100% and positive predictive value of 75.8%. The rate of false positive results was 64%. False negative results were not observed. Conclusion The portal phase presents an excellent sensitivity in the diagnosis of hepatic steatosis, as compared with the non-contrast-enhanced phase of abdominal computed tomography. However, the method has low specificity.

  6. Diagnosis of hepatic steatosis by contrast-enhanced abdominal computed tomography

    International Nuclear Information System (INIS)

    Monjardim, Rodrigo da Fonseca; Costa, Danilo Manuel Cerqueira; Romano, Ricardo Francisco Tavares; Salvadori, Priscila Silveira; Santos, Jaime de Vargas Conde dos; Atzingen, Augusto Castelli Von; Shigueoka, David Carlos; D'Ippolito, Giuseppe

    2013-01-01

    Objective: to evaluate the diagnostic capacity of abdominal computed tomography in the assessment of hepatic steatosis using the portal phase with a simplified calculation method as compared with the non-contrast-enhanced phase. Materials and methods: in the present study, 150 patients were retrospectively evaluated by means of non-contrast-enhanced and contrast-enhanced computed tomography. One hundred patients had hepatic steatosis and 50 were control subjects. For the diagnosis of hepatic steatosis in the portal phase, the authors considered a result of < 104 HU calculated by the formula [L - 0.3 × (0.75 × P + 0.25 × A)] / 0.7, where L, P and A represent the attenuation of the liver, of the main portal vein and abdominal aorta, respectively. Sensitivity, specificity, positive and negative predictive values were calculated, using non-contrast-enhanced computed tomography as the reference standard. Results: the simplified calculation method with portal phase for the diagnosis of hepatic steatosis showed 100% sensitivity, 36% specificity, negative predictive value of 100% and positive predictive value of 75.8%. The rate of false positive results was 64%. False negative results were not observed. Conclusion: The portal phase presents an excellent sensitivity in the diagnosis of hepatic steatosis, as compared with the non-contrast-enhanced phase of abdominal computed tomography. However, the method has low specificity. (author)

  7. Value of fat suppression and dynamic contrast-enhanced MRI in the diagnosis of insulinoma

    International Nuclear Information System (INIS)

    Xu Zengbin; Ruan Lingxiang; Peng Zhiyi; Zhang Minming; Xu Shunliang; Zhang Xidao

    2003-01-01

    Objective: To evaluate the value of fat suppression and dynamic contrast-enhanced MRI in the preoperative localization of insulinoma. Methods: Twelve cases with pathologically proven insulinoma were evaluated with MRI. SE T 1 WI, FSE T 2 WI, T 1 WI and T 2 WI with fat suppression, dynamic contrast-enhanced FMPSPGR sequences were used in MR scanning. Results: On SE T 1 WI, the lesions displayed hypointense in 4, isointense in 8 cases. Lesions showed hyperintense in 4, isointense in 8 cases on FSE T 2 WI. In contrast, 7 cases appeared as hypointense on T 1 WI with fat suppression and 6 cases appeared as hyperintense on T 2 WI with fat suppression. With dynamic contrast-enhanced FMPSPGR sequence 11 of 12 insulinomas were detected. In the arterial phase, the lesions presented as hyperintense with different degrees in 11 cases and isointense in 1 case. 6 cases remained hyperintense and 6 cases were isointense in pancreatic parenchymal and portal phase. 4 lesions were identified only in dynamic enhancement images. The diagnostic accuracy of insulinoma by dynamic contrast-enhanced MRI was 91.7% (11/12) as compared with histological study. Conclusion: The results indicate that dynamic contrast-enhanced MRI is an sensitive and accurate method for the preoperative localization of insulinoma

  8. Study of proximal femoral bone perfusion with 3D T1 dynamic contrast-enhanced MRI: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Budzik, Jean-Francois [Groupe Hospitalier de l' Institut Catholique de Lille / Faculte Libre de Medecine, Service d' Imagerie Medicale, Lille (France); Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHRU de Lille, Service de Radiologie et Imagerie Musculosquelettique, Lille (France); Universite Catholique de Lille, Lille (France); Universite Nord de France, Lille (France); EA 4490 PMOI (Physiopathologie des Maladies Osseuses Inflammatoires) IFR 114 PRES Universite Lille Nord de France, Lille (France); Lefebvre, Guillaume; El Rafei, Mazen [Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHRU de Lille, Service de Radiologie et Imagerie Musculosquelettique, Lille (France); Universite Nord de France, Lille (France); CHU Lille, Lille (France); Forzy, Gerard [Universite Catholique de Lille, Lille (France); Universite Nord de France, Lille (France); Groupe Hospitalier de l' Institut Catholique de Lille, Laboratoire de Biologie, Departement de Biostatistiques, Lille (France); Chechin, David [Philips Medical Systems, Suresnes (France); Cotten, Anne [Centre de Consultation et d' Imagerie de l' Appareil Locomoteur, CHRU de Lille, Service de Radiologie et Imagerie Musculosquelettique, Lille (France); Universite Nord de France, Lille (France); EA 4490 PMOI (Physiopathologie des Maladies Osseuses Inflammatoires) IFR 114 PRES Universite Lille Nord de France, Lille (France); CHU Lille, Lille (France)

    2014-12-15

    The objective of this study was to compare measurements of semi-quantitative and pharmacokinetic parameters in areas of red (RBM) and yellow bone marrow (YBM) of the hip, using an in-house high-resolution DCE T1 sequence, and to assess intra- and inter-observer reproducibility of these measurements. The right hips of 21 adult patients under 50 years of age were studied. Spatial resolution was 1.8 x 1.8 x 1.8 mm{sup 3}, and temporal resolution was 13.5 seconds. Two musculoskeletal radiologists independently processed DCE images and measured semi-quantitative and pharmacokinetic parameters in areas of YBM and RBM. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated. Intra- and inter-observer reproducibility was assessed. Area under the curve (AUC) and initial slope (IS) were significantly greater for RBM than for YBM (p < 0.05). K{sup trans} and k{sub ep} were also significantly greater for RBM (p < 0.05). There was no significant difference in time to peak between the regions (p < 0.05). SNR, CNR, and intra- and inter-observer reproducibility were all good. DCE study of the whole hip is feasible with high spatial resolution using a 3D T1 sequence. Measures were possible even in low vascularized areas of the femoral head. K{sup trans}, k{sub ep}, AUC, and IS values were significantly different between red and yellow marrow, whereas TTP values were not. (orig.)

  9. Evaluation of pathological features of hepatocellular carcinoma by contrast-enhanced ultrasonography: Comparison with pathology on resected specimen

    International Nuclear Information System (INIS)

    Ogawa, Sadanobu; Kumada, Takashi; Toyoda, Hidenori; Ichikawa, Hideo; Kawachi, Toshiaki; Otobe, Katsuhiko; Hibi, Toshio; Takeshima, Kenji; Kiriyama, Seiki; Sone, Yasuhiro; Tanikawa, Makoto; Hisanaga, Yasuhiro; Yamaguchi, Akihiro; Isogai, Masatoshi; Kaneoka, Yuji; Washizu, Junji

    2006-01-01

    Features of hepatocellular carcinoma (HCC) observed by contrast-enhanced ultrasonography (CEUS) were compared to pathological features of corresponding resected HCC specimens, to evaluate the ability of CEUS to depict the pathological features of HCC. We investigated 50 HCC nodules that were treated by surgical resection. All nodules had been examined by CEUS with intravenous contrast agent (Levovist) before surgery. CEUS findings were divided into three phases for evaluation and classification of enhancement patterns: two vascular phases (arterial phase and portal venous phase) and the delayed phase. Pathological examination focused on differentiation and on the presence or absence of a tumor capsule, intratumoral septum, and intratumoral necrosis. All 21 nodules that showed a linear or annular vessel around the tumor margin in the arterial phase had capsular formation. Of the 27 nodules that showed heterogeneous perfusion in the portal venous phase, 21 (77.8%) had an intratumoral septum and 23 (85.2%) showed intratumoral necrosis. All nodules that were depicted as a defect with an unclear margin in the delayed phase were well-differentiated HCCs, whereas all nodules that were depicted as a defect with a clear margin were moderately or poorly differentiated HCCs. From our observations, the arterial, portal venous, and delayed phases of CEUS could reflect different pathological aspects of HCC. Some pathological characteristics of HCC might be evaluated preoperatively and non-invasively, by means of combined analysis of three phases of CEUS findings

  10. Quantification of traumatic meningeal injury using dynamic contrast enhanced (DCE) fluid-attenuated inversion recovery (FLAIR) imaging

    Science.gov (United States)

    Castro, Marcelo A.; Williford, Joshua P.; Cota, Martin R.; MacLaren, Judy M.; Dardzinski, Bernard J.; Latour, Lawrence L.; Pham, Dzung L.; Butman, John A.

    2016-03-01

    Traumatic meningeal injury is a novel imaging marker of traumatic brain injury, which appears as enhancement of the dura on post-contrast T2-weighted FLAIR images, and is likely associated with inflammation of the meninges. Dynamic Contrast Enhanced MRI provides a better discrimination of abnormally perfused regions. A method to properly identify those regions is presented. Images of seventeen patients scanned within 96 hours of head injury with positive traumatic meningeal injury were normalized and aligned. The difference between the pre- and last post-contrast acquisitions was segmented and voxels in the higher class were spatially clustered. Spatial and morphological descriptors were used to identify the regions of enhancement: a) centroid; b) distance to the brain mask from external voxels; c) distance from internal voxels; d) size; e) shape. The method properly identified thirteen regions among all patients. The method failed in one case due to the presence of a large brain lesion that altered the mask boundaries. Most false detections were correctly rejected resulting in a sensitivity and specificity of 92.9% and 93.6%, respectively.

  11. Characterization of tumor heterogeneity using dynamic contrast enhanced CT and FDG-PET in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Elmpt, Wouter van; Das, Marco; Hüllner, Martin; Sharifi, Hoda; Zegers, Catharina M.L.; Reymen, Bart; Lambin, Philippe; Wildberger, Joachim E.; Troost, Esther G.C.; Veit-Haibach, Patrick; De Ruysscher, Dirk

    2013-01-01

    Purpose: Dynamic contrast-enhanced CT (DCE-CT) quantifies vasculature properties of tumors, whereas static FDG-PET/CT defines metabolic activity. Both imaging modalities are capable of showing intra-tumor heterogeneity. We investigated differences in vasculature properties within primary non-small cell lung cancer (NSCLC) tumors measured by DCE-CT and metabolic activity from FDG-PET/CT. Methods: Thirty three NSCLC patients were analyzed prior to treatment. FDG-PET/CT and DCE-CT were co-registered. The tumor was delineated and metabolic activity was segmented on the FDG-PET/CT in two regions: low (<50% maximum SUV) and high (⩾50% maximum SUV) metabolic uptake. Blood flow, blood volume and permeability were calculated using a maximum slope, deconvolution algorithm and a Patlak model. Correlations were assessed between perfusion parameters for the regions of interest. Results: DCE-CT provided additional information on vasculature and tumor heterogeneity that was not correlated to metabolic tumor activity. There was no significant difference between low and high metabolic active regions for any of the DCE-CT parameters. Furthermore, only moderate correlations between maximum SUV and DCE-CT parameters were observed. Conclusions: No direct correlation was observed between FDG-uptake and parameters extracted from DCE-CT. DCE-CT may provide complementary information to the characterization of primary NSCLC tumors over FDG-PET/CT imaging

  12. Hyperpolarized Water Perfusion in the Porcine Brain – a Pilot Study

    DEFF Research Database (Denmark)

    Søvsø Szocska Hansen, Esben; Lipsø, Hans Kasper Wigh; Tougaard, Rasmus Stilling

    2017-01-01

    Dynamic Contrast-Enhanced MR (DCE-MR) perfusion assessment with gadolinium contrast agents is currently the most widely used cerebral perfusion MR method. Hyperpolarized water has recently been shown to succeed 13C probes as angiography probe. In this study, we demonstrate the feasibility...... of hyperpolarized water for visualizing the brain vasculature of a large animal in a clinically relevant setting. In detail, reference perfusion values were obtained and large to small arteries could be identified....

  13. Differentiating benign and malignant breast lesions with T2*-weighted first pass perfusion imaging

    International Nuclear Information System (INIS)

    Kvistad, K.A.; Smenes, E.; Haraldseth, O.; Lundgren, S.; Fjoesne, H.E.; Smethurst, H.B.

    1999-01-01

    Purpose: Invasive breast carcinomas and fibroadenomas are often difficult to differentiate in dynamic contrast-enhanced T1-weighted MR imaging of the breast, because both tumors can enhance strongly after contrast injection. The purpose of this study was to evaluate whether the addition of T2*-weighted first pass perfusion imaging can increase the differentiation of malignant from benign lesions. Material and Methods: Nine patients with invasive carcinomas and 10 patients with contrast enhancing fibroadenomas were examined by a dynamic contrast-enhanced T1-weighted 3D sequence immediately followed by a single slice T2*-weighted first pass perfusion sequence positioned in the contrast-enhancing lesion. Results: The carcinomas and the fibroadenomas were impossible to differentiate based on the contrast enhancement characteristics in the T1-weighted sequence. The signal loss in the T2*-weighted perfusion sequence was significantly stronger in the carcinomas than in the fibroadenomas (p=0.0004). Conclusion: Addition of a T2*-weighted first pass perfusion sequence with a high temporal resolution can probably increase the differentiation of fibroadenomas from invasive carcinomas in contrast-enhanced MR imaging of the breast. (orig.)

  14. Dynamic contrast enhanced MRI study of primary primitive neuroectodermal tumor in the thoracic spine

    International Nuclear Information System (INIS)

    Chen Yu; Xu Jianmin; Li Ying; Zhang Jingzhong; Zhu Jing

    2004-01-01

    Objective: To investigate the value of dynamic contrast-enhanced MR imaging in the diagnosis and differentiation of primitive neuroectodermal tumor (PNET) in the thoracic spine. Methods: The dynamic contrast-enhanced MR imaging of 2 patients (3 times) with PNET in the thoracic spine proved by surgery and pathology were prospectively studied. Results: In the curves of SI-time and CER-time, PNET in the thoracic spine showed a rapid rise to the peak between 60 s and 120 s, then the flat level was kept and no obvious decline was detected after about 3.5 minute. Conclusion: Dynamic contrast-enhanced MRI can help to make the diagnosis and differential diagnosis for PNET in the thoracic spine, offer reliable information for the choice of clinical management, and predict the prognosis

  15. Contrast-enhanced power Doppler ultrasonography of the metacarpophalangeal joints in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Szkudlarek, Marcin; Court-Payen, Michel; Strandberg, Charlotte

    2003-01-01

    The aim of this study was to examine, with dynamic contrast-enhanced MRI as the reference, if contrast-enhanced power Doppler ultrasonography (CE PDUS) of rheumatoid arthritis (RA) metacarpophalangeal (MCP) joints provides additional information for evaluation of synovial inflammation compared...... with PDUS. One MCP joint in each of 15 RA patients and 3 healthy control persons were examined with PDUS before and after intravenous bolus Levovist contrast injection. Corresponding rates of early synovial enhancement (RESE), previously shown to be closely related to histopathological synovitis, were...... calculated from dynamic contrast-enhanced MR images obtained the same day. Prior to ultrasonography, the joint was evaluated clinically. Levovist increased the flow signal in 7 of 9 joints with pre-contrast flow-signal and in 0 of 9 without pre-contrast signal. No healthy controls showed CE PDUS signal...

  16. Dynamic contrast-enhanced subtraction MR angiography in intracranial vascular abnormalities

    International Nuclear Information System (INIS)

    Takano, K.; Ono, H.; Utsunomiya, H.; Okazaki, M.; Tanaka, A.

    1999-01-01

    We present our clinical experience with dynamic contrast-enhanced MR angiography (MRA) with subtraction for assessing intracranial vascular abnormalities. Ten patients with various cerebrovascular disorders underwent dynamic contrast-enhanced MRA on a 1.0-T system. Thirty sections (2 mm) were acquired in 29-30 s. Maximum intensity projection images and subtracted source images were compared with those obtained by conventional angiography. In all cases, the presence or absence of abnormalities in the targeted vessels, as well as the morphology of the sagittal sinuses, was clearly visualized as in conventional angiography, without any obstructions such as hyperintense hematomas or thrombi, or intraluminal turbulence. Although the temporal and spatial resolutions with current hardware are insufficient, these preliminary results suggest that dynamic contrast-enhanced MRA with subtraction may be useful for assessing vascular lesions with hemorrhage or thrombus, and the dural sinuses. (orig.)

  17. Delayed contrast-enhanced MRI: use in myocardial viability assessment and other cardiac pathology

    International Nuclear Information System (INIS)

    Bogaert, J.; Dymarkowski, S.

    2005-01-01

    As in other organs, tissue characterization is important for many cardiac diseases. For example, in ischemic heart disease, differentiation between reversibly and irreversibly damaged myocardium in patients with a prior myocardial infarction is crucial in determining disease severity, functional recovery and patient outcome. With the recent advent of the single inversion-recovery contrast-enhanced magnetic resonance imaging (MRI) sequence (delayed contrast-enhanced MRI), contrast between normal and abnormal tissues could be significantly enhanced compared with the conventional cardiac MRI sequences, enabling even subtle abnormalities to be visualized. Together with other advances in cardiac MRI (e.g. functional imaging, coronary artery imaging), MRI has become one of the preferred non-invasive modalities to study cardiac diseases. In this paper an overview of the versatility of delayed contrast-enhanced MRI for investigating cardiac diseases is given. (orig.)

  18. The role of contrast-enhanced ultrasound in risk assessment of carotid atheroma

    Directory of Open Access Journals (Sweden)

    Silviu Stanciu

    2016-07-01

    Full Text Available Background and objective: Contrast-enhanced ultrasound, used to assess atherosclerotic carotid plaques, improves visualization of vessel wall irregularities and depicts intraplaque neovascularization. This article illustrates the use of contrast-enhanced ultrasound in the risk assessment of carotid atherosclerotic lesions, especially in challenging plaques evaluation. Materials and methods: For 23 patients with difficult duplex ultrasound examination due to carotid tortuosity or calcifications we assessed plaque morphology (contour, echogenicity and stenosis degree using contrast substance (Sonovue, Braco with dedicated vascular low mechanical index CPC software. Conclusion: Contrast-enhanced ultrasound is a new, noninvasive, and safe procedure for imaging carotid atherosclerotic lesions. It is a valuable tool for evaluating the vulnerable plaque at risk for rupture and for the diagnostic of the development and severity of systemic atherosclerotic disease

  19. MRI contrast enhancement of the lung using a Gd-DTPA aerosol

    International Nuclear Information System (INIS)

    Bockisch, A.; Harvey, R.C.; Davis, M.A.; Kabalka, G.W.

    1993-01-01

    A MR imaging study was performed in anesthetized female beagle dogs to investigate the effectiveness of Gd-DTPA aerosol for contrast enhancement in ventilated lungs. Ventilation was performed using a commercially available atomizer to administer Gd-DTPA solution. MR imaging was performed with a 1.9 T whole body imager using respiratory gated acquisition. To define the amount of Gd-DTPA being trapped in the lungs identical experiments were performed with 99m Tc-DTPA. MR imaging confirmed at 70% contrast enhancement following inhalation of Gd-DTPA. Because of the inherently low signal intensity of lung parenchyma the degree of contrast enhancement is not sufficient for clinical application. (orig.) [de

  20. Field strength and dose dependence of contrast enhancement by gadolinium-based MR contrast agents

    International Nuclear Information System (INIS)

    Rinck, P.A.; Muller, R.N.

    1999-01-01

    The relaxivities r 1 and r 2 of magnetic resonance contrast agents and the T 1 relaxation time values of tissues are strongly field dependent. We present quantitative data and simulations of different gadolinium-based extracellular fluid contrast agents and the modulation of their contrast enhancement by the magnetic field to be able to answer the following questions: How are the dose and field dependences of their contrast enhancement? Is there an interrelationship between dose and field dependence? Should one increase or decrease doses at specific fields? Nuclear magnetic relaxation dispersion data were acquired for the following contrast agents: gadopentetate dimeglumine, gadoterate meglumine, gadodiamide injection, and gadoteridol injection, as well as for several normal and pathological human tissue samples. The magnetic field range stretched from 0.0002 to 4.7 T, including the entire clinical imaging range. The data acquired were then fitted with the appropriate theoretical models. The combination of the diamagnetic relaxation rates (R 1 = 1/T 1 and R 2 = 1/T 2 ) of tissues with the respective paramagnetic contributions of the contrast agents allowed the prediction of image contrast at any magnetic field. The results revealed a nearly identical field and dose-dependent increase of contrast enhancement induced by these contrast agents within a certain dose range. The target tissue concentration (TTC) was an important though nonlinear factor for enhancement. The currently recommended dose of 0.1 mmol/kg body weight seems to be a compromise close to the lower limits of diagnostically sufficient contrast enhancement for clinical imaging at all field strengths. At low field contrast enhancement might be insufficient. Adjustment of dose or concentration, or a new class of contrast agents with optimized relaxivity, would be a valuable contribution to a better diagnostic yield of contrast enhancement at all fields. (orig.)

  1. Ultra-high field upper extremity peripheral nerve and non-contrast enhanced vascular imaging.

    Directory of Open Access Journals (Sweden)

    Shailesh B Raval

    Full Text Available The purpose of this study was to explore the efficacy of Ultra-high field [UHF] 7 Tesla [T] MRI as compared to 3T MRI in non-contrast enhanced [nCE] imaging of structural anatomy in the elbow, forearm, and hand [upper extremity].A wide range of sequences including T1 weighted [T1] volumetric interpolate breath-hold exam [VIBE], T2 weighted [T2] double-echo steady state [DESS], susceptibility weighted imaging [SWI], time-of-flight [TOF], diffusion tensor imaging [DTI], and diffusion spectrum imaging [DSI] were optimized and incorporated with a radiofrequency [RF] coil system composed of a transverse electromagnetic [TEM] transmit coil combined with an 8-channel receive-only array for 7T upper extremity [UE] imaging. In addition, Siemens optimized protocol/sequences were used on a 3T scanner and the resulting images from T1 VIBE and T2 DESS were compared to that obtained at 7T qualitatively and quantitatively [SWI was only qualitatively compared]. DSI studio was utilized to identify nerves based on analysis of diffusion weighted derived fractional anisotropy images. Images of forearm vasculature were extracted using a paint grow manual segmentation method based on MIPAV [Medical Image Processing, Analysis, and Visualization].High resolution and high quality signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]-images of the hand, forearm, and elbow were acquired with nearly homogeneous 7T excitation. Measured [performed on the T1 VIBE and T2 DESS sequences] SNR and CNR values were almost doubled at 7T vs. 3T. Cartilage, synovial fluid and tendon structures could be seen with higher clarity in the 7T T1 and T2 weighted images. SWI allowed high resolution and better quality imaging of large and medium sized arteries and veins, capillary networks and arteriovenous anastomoses at 7T when compared to 3T. 7T diffusion weighted sequence [not performed at 3T] demonstrates that the forearm nerves are clearly delineated by fiber tractography. The

  2. Dynamic contrast-enhanced MR of the prostatic cancer and benign prostatic hyperplasia: correlation with angiogenesis

    International Nuclear Information System (INIS)

    Ni Xinchu; Shen Junkang; Lu Zhian; Zhou Lijuan; Yang Xiaochun; Wang Guanzhong; Zhang Caiyuan; Wang Shuizhen; Qian Minghui; Chan Yuxi; Qian Nong; Xiang Jianpo; Pan Changjie; Rong Weiliang; Chen Jianguo

    2005-01-01

    Objective: To evaluate the role of dynamic contrast-enhanced magnetic resonance imaging (MRI) in the diagnose of prostatic cancer and benign prostatic hyperplasia (BPH), and to determine the correlation between dynamic MRI findings with angiogenesis. Methods: Thirty-two cases of prostatic cancer and 40 cases of BPH underwent dynamic contrast-enhanced MRI. All the patients in this study were diagnosed by histopathology. The results of dynamic contrast-enhanced MRI were evaluated by early-phase enhancement parameters and time-signal intensity curves (SI-T curves), and the curves were classified according to their shapes as type I, which had steady enhancement; type II, plateau of signal intensity; and type III, washout of signal intensity. The pathologic specimens of region of interest (ROI ) were obtained, and HE staining, immunohistochemical vascular endothelial growth factor (VEGF), and microvessel density (MVD) measurements were performed. The relationships among dynamic contrast-enhanced MRI features, VEGF, and MVD expression were analyzed. Results: In the early-phase enhancement parameters of dynamic contrast-enhanced MRI, onset time, maximum signal intensity, and early-phase enhancement rate differed between prostatic cancer and BPH (P<0.01, 0.05, 0.01), but there were some overlaps between them. The intermediate and late post-contrast periods were characterized with the lesion SI-T curves. The SI-T curve of prostatic cancer was mainly type III (21 cases). Type II could be seen in both prostatic cancer (8 cases) and BPH (19 cases). Type I most appeared in BPH (18 cases). The distributions proved to have significant difference (P<0.001). The mean VEGF and MVD level of 32 prostatic cancer patients were significantly higher than those of 40 BPH patients (P<0.001). MVD level of prostatic cancer and BPH showed an association with VEGF level (P<0.01). The maximum signal intensity and early-phase enhancement rate in both prostatic cancer and BPH showed an association

  3. Contrast enhancement of cerebral infarcts. Incidence and clinical value in different states of cerebral infarction

    International Nuclear Information System (INIS)

    Skriver, E.B.; Olsen, T.S.

    1982-01-01

    Information obtained from CT scan after contrast administration was evaluated in 59 consecutive stroke patients. CT scans before and after contrast administration were performed 3 days and 2 1/2 weeks after stroke. A plain CT scan was repeated 6 months later. Contrast enhancement was practically not seen on the first examination, but was seen in 46% on the second examination. There was a close relationship between the occurrence of contrast enhancement and the so called fogging effect. Contrast scanning gave additional information only when this effect was present. Plain CT scans 3 days after stroke were superior to contrast scans taken at any time for detecting and visualizing cerebral infarcts. (orig.)

  4. B-mode and contrast-enhanced sonographic assessment of accessory spleen in the dog.

    Science.gov (United States)

    Rossi, Federica; Rabba, Silvia; Vignoli, Massimo; Haers, Hendrik; Terragni, Rossella; Saunders, Jimmy H

    2010-01-01

    Four dogs with an accessory spleen are described. The accessory spleens appeared as a round-to-triangular structure located in the perisplenic area. They were homogeneous and isoechoic with the adjacent spleen. Contrast-enhanced ultrasound was performed using a second generation microbubble contrast medium (sulfur hexafluoride). The type and timing of enhancement of the accessory spleen was similar to that of the parent spleen. Contrast-enhanced ultrasound is a noninvasive modality useful in distinguishing an accessory spleen from a mass of another origin.

  5. Regions of low density in the contrast-enhanced pituitary gland: normal and pathologic processes

    International Nuclear Information System (INIS)

    Chambers, E.F.; Turski, P.A.; LaMasters, D.; Newton, T.H.

    1982-01-01

    The incidence of low-density regions in the contrast-enhanced pituitary gland and the possible causes of these regions were investigated by a retrospective review of computed tomographic (CT) scans of the head in 50 patients and autopsy specimens of the pituitary in 100 other patients. It was found that focal areas of low density within the contrast enhanced pituitary gland can be caused by various normal and pathologic conditions such as pituitary microadenomas, pars intermedia cysts, foci of metastasis, infarcts, epidermoid cysts, and abscesses. Although most focal low-density regions probably represent pituitary microadenomas, careful clinical correlation is needed to establish a diagnosis

  6. Differential diagnosis between pulmonary tuberculosis and lung abscess by contrast enhanced CT

    International Nuclear Information System (INIS)

    Kanauchi, Tetsu; Hoshi, Toshiko; Konno, Miyuki; Hando, Yumiko

    2001-01-01

    The contrast enhanced CT findings in 14 patients with active tuberculosis and 26 patients with lung abscess were retrospectively analyzed. Reflecting the difference of pathogenesis between tuberculosis and abscess, the findings are widely different. The findings suggesting pulmonary tuberculosis rather than lung abscess were as follows; multiple and irregular necrotic areas, positive CT angiogram sign, no marginal enhancement surrounding necrosis. Contrast enhanced CT may help to distinguish pulmonary tuberculosis from lung abscess, especially in cases of caseous pneumonia showing broad consolidations or mass-like shadows. (author)

  7. Independent component analysis of dynamic contrast-enhanced computed tomography images

    Energy Technology Data Exchange (ETDEWEB)

    Koh, T S [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798 (Singapore); Yang, X [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798 (Singapore); Bisdas, S [Department of Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University Hospital, Theodor-Stern-Kai 7, D-60590 Frankfurt (Germany); Lim, C C T [Department of Neuroradiology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433 (Singapore)

    2006-10-07

    Independent component analysis (ICA) was applied on dynamic contrast-enhanced computed tomography images of cerebral tumours to extract spatial component maps of the underlying vascular structures, which correspond to different haemodynamic phases as depicted by the passage of the contrast medium. The locations of arteries, veins and tumours can be separately identified on these spatial component maps. As the contrast enhancement behaviour of the cerebral tumour differs from the normal tissues, ICA yields a tumour component map that reveals the location and extent of the tumour. Tumour outlines can be generated using the tumour component maps, with relatively simple segmentation methods. (note)

  8. Perfusion CT in childhood stroke—Initial observations and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Zebedin, D., E-mail: doris.zebedin@medunigraz.at [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria); Sorantin, E.; Riccabona, M. [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria)

    2013-07-15

    Introduction: To report the preliminary results of contrast-enhanced perfusion multi-detector CT for diagnoses of perfusion disturbances in children with clinical suspicion of stroke. Patients and methods: Within the last two years emergency perfusion CT was performed in ten children (age: 8–17 years, male:female = 3:7) for assessment of suspected childhood stroke. These intracranial perfusion CT, intracranial CT-digital subtraction angiography (CT-DSA) and extracranial CT-angiography (CTA) studies were retrospectively reviewed and compared with MRI, follow-up CT, catheter angiography and final clinical diagnosis. The total dose length product (DLP) for the entire examination was recorded. The image quality of perfusion CT-maps, CT-DSA and CTA were evaluated with a subjective three-point scale ranging from very good to non-diagnostic image quality rating perfusion disturbance, intracranial peripheral vessel depiction, and motion- or streak artifacts. Results: In nine of ten children perfusion CT showed no false positive or false negative results. In one of ten children suffering from migraine focal hypo-perfusion was read as perfusion impairment potentially indicating early stroke, but MRI and MRA follow-up were negative. Overall, perfusion-CT with CT-DSA was rated very good in 80% of cases for the detection of perfusion disturbances and vessel anatomy. Conclusions: In comparison to standard CT, contrast-enhanced perfusion CT improves CTs’ diagnostic capability in the emergency examination of children with a strong suspicion of ischemic cerebral infarction.

  9. Early evaluation of irradiated parotid glands with intravoxel incoherent motion MR imaging: correlation with dynamic contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Zhou, Nan; Chu, Chen; Dou, Xin; Li, Ming; Liu, Song; Zhu, Lijing; Liu, Baorui; Guo, Tingting; Chen, Weibo; He, Jian; Yan, Jing; Zhou, Zhengyang; Yang, Xiaofeng; Liu, Tian

    2016-01-01

    Radiation-induced parotid damage is one of the most common complications in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy (RT). Intravoxel incoherent motion (IVIM) magnetic resonance (MR) imaging has been reported for evaluating irradiated parotid damage. However, the changes of IVIM perfusion-related parameters in irradiated parotid glands have not been confirmed by conventional perfusion measurements obtained from dynamic contrast-enhanced (DCE) MR imaging. The purposes of this study were to monitor radiation-induced parotid damage using IVIM and DCE MR imaging and to investigate the correlations between changes of these MR parameters. Eighteen NPC patients underwent bilateral parotid T1-weighted, IVIM and DCE MR imaging pre-RT (2 weeks before RT) and post-RT (4 weeks after RT). Parotid volume; IVIM MR parameters, including apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f); and DCE MR parameters, including maximum relative enhancement (MRE), time to peak (TTP), Wash in Rate, and the degree of xerostomia were recorded. Correlations of parotid MR parameters with mean radiation dose, atrophy rate and xerostomia degree, as well as the relationships between IVIM and DCE MR parameters, were investigated. From pre-RT to post-RT, all of the IVIM and DCE MR parameters increased significantly (p < 0.001 for ADC, D, f, MRE, Wash in Rate; p = 0.024 for D*; p = 0.037 for TTP). Change rates of ADC, f and MRE were negatively correlated with atrophy rate significantly (all p < 0.05). Significant correlations were observed between the change rates of D* and MRE (r = 0.371, p = 0.026) and between the change rates of D* and TTP (r = 0.396, p = 0.017). The intra- and interobserver reproducibility of IVIM and DCE MR parameters was good to excellent (intraclass correlation coefficient, 0.633–0.983). Early radiation-induced changes of parotid glands could be evaluated by IVIM and

  10. Alterations of the Blood-Brain Barrier and Regional Perfusion in Tumor Development: MRI Insights from a Rat C6 Glioma Model.

    Science.gov (United States)

    Huhndorf, Monika; Moussavi, Amir; Kramann, Nadine; Will, Olga; Hattermann, Kirsten; Stadelmann, Christine; Jansen, Olav; Boretius, Susann

    2016-01-01

    Angiogenesis and anti-angiogenetic medications play an important role in progression and therapy of glioblastoma. In this context, in vivo characterization of the blood-brain-barrier and tumor vascularization may be important for individual prognosis and therapy optimization. We analyzed perfusion and capillary permeability of C6-gliomas in rats at different stages of tumor-growth by contrast enhanced MRI and dynamic susceptibility contrast (DSC) MRI at 7 Tesla. The analyses included maps of relative cerebral blood volume (CBV) and signal recovery derived from DSC data over a time period of up to 35 days after tumor cell injections. In all rats tumor progression was accompanied by temporal and spatial changes in CBV and capillary permeability. A leakage of the blood-brain barrier (slow contrast enhancement) was observed as soon as the tumor became detectable on T2-weighted images. Interestingly, areas of strong capillary permeability (fast signal enhancement) were predominantly localized in the center of the tumor. In contrast, the tumor rim was dominated by an increased CBV and showed the highest vessel density compared to the tumor center and the contralateral hemisphere as confirmed by histology. Substantial regional differences in the tumor highlight the importance of parameter maps in contrast or in addition to region-of-interest analyses. The data vividly illustrate how MRI including contrast-enhanced and DSC-MRI may contribute to a better understanding of tumor development.

  11. Dynamic contrast-enhanced imaging of the wrist in rheumatoid arthritis: dedicated low-field (0.25-T) versus high-field (3.0-T) MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ryan K.L.; Griffith, James F.; Wang, D.F.; Yeung, David K.W. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Hong Kong, SAR (China); Shi, L. [The Chinese University of Hong Kong, Department of Medicine and Therapeutics, Division of Neurology, Hong Kong, SAR (China); Li, Edmund K.; Tam, L.S. [The Chinese University of Hong Kong, Department of Medicine, Division of Rheumatology, Prince Of Wales Hospital, Hong Kong, SAR (China)

    2015-08-15

    To compare the assessment of wrist synovitis severity, synovial volume and synovial perfusion parameters on a dedicated low-field (0.25-T) to that of a high-field (3-T) whole-body MR system in patients with rheumatoid arthritis (RA). Twenty-one patients (mean age 50.0 ± 9.8 years) with active RA were recruited prospectively. Dynamic contrast-enhanced MRI examination of the most severely affected wrist was performed at both 0.25 T and 3 T. Three MRI-derived parameters, synovitis severity (RAMRIS grade), synovial volume (ml{sup 3}) and synovial perfusion indices (maximum enhancement and enhancement slope), were compared. Comparing 0.25- and 3-T MRI, there was excellent agreement for semiquantitative assessment (r: 0.80, p < 0.00001) of synovitis (RAMRIS) as well as quantitative assessment (r: 0.94, p < 0.00001) of synovial volume. Good agreement for synovial Emax (r: 0.6, p = 0.002) and fair agreement (r: 0.5, p = 0.02) for synovial Eslope was found. Imaging of the RA wrist at 0.25 T yields excellent correlation with 3 T with regard to the synovitis activity score (RAMRIS) and synovial volume measurement. Fair to good correlation between low- (0.25-T) and high-field (3-T) MR systems was found for perfusion parameters, being better for Emax than for Eslope. (orig.)

  12. Contrast-Enhanced Ultrasound and Near-Infrared Spectroscopy of the Neonatal Bowel: Novel, Bedside, Noninvasive, and Radiation-Free Imaging for Early Detection of Necrotizing Enterocolitis.

    Science.gov (United States)

    Al-Hamad, Suzanne; Hackam, David J; Goldstein, Seth D; Huisman, Thierry A G M; Darge, Kassa; Hwang, Misun

    2018-05-31

    Despite extensive research and improvements in the field of neonatal care, the morbidity and mortality associated with necrotizing enterocolitis (NEC) have remained unchanged over the past three decades. Early detection of ischemia and necrotic bowel is vital in improving morbidity and mortality associated with NEC; however, strategies for predicting and preventing NEC are lacking. Contrast-enhanced ultrasound (CEUS) and near-infrared spectroscopy (NIRS) are novel techniques in pediatrics that have been proven as safe modalities. CEUS has benefits over conventional ultrasound (US) by its improved real-time evaluation of the micro- and macrovascularities of normally and abnormally perfused tissue. US has been implemented as a useful adjunct to X-ray for earlier evaluation of NEC. NIRS is another noninvasive technique that has shown promise in improving early detection of NEC. The purpose of this article is to review the current understanding of changes in bowel perfusion in NEC, discuss the accuracy of abdominal US in detecting NEC, and explain how the use of CEUS and NIRS will enhance the precise and early detection of altered/pathological bowel wall perfusion in the initial development and course of NEC. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  13. Initial experience of correlating parameters of intravoxel incoherent motion and dynamic contrast-enhanced magnetic resonance imaging at 3.0 T in nasopharyngeal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Qian-Jun; Zhang, Shui-Xing; Chen, Wen-Bo; Liang, Long; Zhou, Zheng-Gen; Liu, Zai-Yi; Zeng, Qiong-Xin; Liang, Chang-Hong [Guangdong General Hospital/Guangdong Academy of Medical Sciences, Department of Radiology, Guangzhou, Guangdong Province (China); Qiu, Qian-Hui [Guangdong General Hospital/Guangdong Academy of Medical Sciences, Department of Otolaryngology, Guangzhou, Guangdong Province (China)

    2014-12-15

    To determine the correlation between intravoxel incoherent motion (IVIM) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters. Thirty-eight newly diagnosed NPC patients were prospectively enrolled. Diffusion-weighted images (DWI) at 13 b-values were acquired using a 3.0-T MRI system. IVIM parameters including the pure molecular diffusion (D), perfusion-related diffusion (D*), perfusion fraction (f), DCE-MRI parameters including maximum slope of increase (MSI), enhancement amplitude (EA) and enhancement ratio (ER) were calculated by two investigators independently. Intra- and interobserver agreement were evaluated using the intraclass correlation coefficient (ICC) and Bland-Altman analysis. Relationships between IVIM and DCE-MRI parameters were evaluated by calculation of Spearman's correlation coefficient. Intra- and interobserver reproducibility were excellent to relatively good (ICC = 0.887-0.997; narrow width of 95 % limits of agreement). The highest correlation was observed between f and EA (r = 0.633, P < 0.001), with a strong correlation between f and MSI (r = 0.598, P = 0.001). No correlation was observed between f and ER (r = -0.162; P = 0.421) or D* and DCE parameters (r = 0.125-0.307; P > 0.119). This study suggests IVIM perfusion imaging using 3.0-T MRI is feasible in NPC, and f correlates significantly with EA and MSI. (orig.)

  14. A Unifying model of perfusion and motion applied to reconstruction of sparsely sampled free-breathing myocardial perfusion MRI

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Ólafsdóttir, Hildur; Larsen, Rasmus

    2010-01-01

    The clinical potential of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is currently limited by respiratory induced motion of the heart. This paper presents a unifying model of perfusion and motion in which respiratory motion becomes an integral part of myocardial perfusion...... quantification. Hence, the need for tedious manual motion correction prior to perfusion quantification is avoided. In addition, we demonstrate that the proposed framework facilitates the process of reconstructing DCEMRI from sparsely sampled data in the presence of respiratory motion. The paper focuses primarily...... on the underlying theory of the proposed framework, but shows in vivo results of respiratory motion correction and simulation results of reconstructing sparsely sampled data....

  15. Dynamic contrast-enhanced MRI in patients with luminal Crohn's disease

    NARCIS (Netherlands)

    Ziech, M. L. W.; Lavini, C.; Caan, M. W. A.; Nio, C. Y.; Stokkers, P. C. F.; Bipat, S.; Ponsioen, C. Y.; Nederveen, A. J.; Stoker, J.

    2012-01-01

    Objectives: To prospectively assess dynamic contrast-enhanced (DCE-)MRI as compared to conventional sequences in patients with luminal Crohn's disease. Methods: Patients with Crohn's disease undergoing MRI and ileocolonoscopy within 1 month had DCE-MRI (3T) during intravenous contrast injection of

  16. Contrast enhancement of focal hepatic lesions in CT: effect of size and histology

    International Nuclear Information System (INIS)

    Burgener, F.A.; Hamlin, D.J.

    1983-01-01

    The effect of size and histology on the contrast enhancement of hepatic lesions has been analyzed in this clinical and experimental investigation yielding the following results: (1) The attenuation values of hepatic cysts in patients increase significantly and inversely with their size after contrast enhancement when the cysts measure less than twice the CT-slice thickness. This seems to be caused by partial-volume effect. (2) Experimental tumors of identical sizes and originating from the same cell line can demonstrate different contrast-enhancement patterns. (3) Peak contrast uptake in both experimental and human tumors seems to be inversely related to their size. (4) Compared to liver, contrast washout from experimental and human tumors (presumably the extravascular space) is delayed. The delay in the contrast washout from a tumor seems to correlate with tumor size. These findings suggest that in general, it is not possible to differentiate reliably among various hepatic neoplasms on the basis of their contrast enhancement patterns for the following reasons: (1) Attenuation values of small hepatic neoplasms are distorted by partial volume effect. (2) Tumors of different histologies can demonstrate the same enhancement pattern. (3) Tumors of identical histology and size can demonstrate different enhancement patterns. (4) The enhancement pattern of a tumor changes with growth or size

  17. Evaluation of delayed contrast-enhanced CT scan in diagnosing hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Li Jianding; Liang Chenyang; Zhang Hua; Zhang Yuezhen; Li Rui

    2001-01-01

    Objective: To assess the diagnostic value of delayed CT contrast enhancement patterns in hilar cholangiocarcinoma based on two-phased dynamic incremental CT scanning. Methods: Fifty-two patients with suspected hilar tumor and bile duct obstruction underwent spiral CT scan. The scan time for one revolution of the X-ray tube was 1 second. To elucidate the delay time for optimal imaging, all proved cholangiocarcinoma with delayed (6, 8, 10, 15, 20, 30 minutes) post-equilibrium-phase contrast-enhanced CT scans were acquired with unenhanced, dynamic contrast-enhanced, and delayed images. Degree of delayed enhancement was compared with that of surrounding liver parenchyma. Results: (1) 8-15 minutes after IV injection of contrast material was the delay time for optimal imaging. (2) Of 29 cholangiocarcinomas, the early CT showed hypo-attenuating (lower than that of liver parenchyma) in 23 tumors, iso-attenuating (equal to that of the liver) in 4 tumors, and hyper-attenuating (higher than that of liver) in 2 tumors. The delayed CT scan showed iso-attenuating in 8 tumors, hyper-attenuating in 21 tumors, and no hypo-attenuating. Most of delay imaging of hilar cholangiocarcinoma may appear hyper-attenuating (U = -4.3073, P 2 = 9.09, P < 0.01). Conclusion: When assessing hilar tumor, delayed CT contrast enhancement patterns based on two-phase dynamic incremental CT scans is useful in the detection and characterization of hilar cholangiocarcinoma

  18. Medical Image Visual Appearance Improvement Using Bihistogram Bezier Curve Contrast Enhancement: Data from the Osteoarthritis Initiative

    Science.gov (United States)

    Gan, Hong-Seng; Swee, Tan Tian; Abdul Karim, Ahmad Helmy; Sayuti, Khairil Amir; Abdul Kadir, Mohammed Rafiq; Tham, Weng-Kit; Wong, Liang-Xuan; Chaudhary, Kashif T.; Yupapin, Preecha P.

    2014-01-01

    Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of “adequate contrast enhancement” to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image's maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher's Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection. PMID:24977191

  19. Abducens nerve enhancement demonstrated by multiplanar reconstruction of contrast-enhanced three-dimensional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hosoya, T.; Adachi, M.; Sugai, Y. [Dept. of Radiology, Yamagata University School of Medicine (Japan); Yamaguchi, K.; Yamaguchi, K. [Dept. of Ophthalmology, Yamagata University School of Medicine (Japan); Kato, T. [3. Dept. of Internal Medicine, Yamagata University School of Medicine (Japan)

    2001-04-01

    We describe contrast enhancement of the cisternal portion of the abducens nerve and discuss its clinical significance. We examined 67 patients with ophthalmoplegia using contrast-enhanced 3-dimensional (3D) MRI with multiplanar reconstruction along the nerves and found 16 patients (ten men, six women), aged 10-73 years (mean 34.4 years), with contrast enhancement of the abducens nerve. Of the 36 patients who had an abducens palsy, 14 (39 %) showed contrast enhancement. In the 16 patients, 23 abducens nerves enhanced; 13 were symptomatic and 10 asymptomatic at the time. The causes were disseminated tumour (1), an inflammatory process (3), trauma (2), ischaemia (2) and autoimmune diseases (8), such as the Miller Fisher syndrome, acute ophthalmoparesis, polyneuropathy and multiple sclerosis. Abducens and/or oculomotor nerve enhancement was the only abnormality on MRI in the patients with traumatic or ischaemic neuropathy or autoimmune diseases. There were 14 patients who recovered fully within 1-6 months after treatment, and resolution of the enhancement correlated well with recovery. (orig.)

  20. Feasibility of contrast-enhanced cone-beam CT for target localization and treatment monitoring

    International Nuclear Information System (INIS)

    Rodal, Jan; Sovik, Aste; Skogmo, Hege Kippenes; Knudtsen, Ingerid Skjei; Malinen, Eirik

    2010-01-01

    A dog with a spontaneous maxillary tumour was given 40 Gy of fractionated radiotherapy. At five out of 10 fractions cone-beam CT (CBCT) imaging before and after administration of an iodinated contrast agent were performed. Contrast enhancement maps were overlaid on the pre-contrast CBCT images. The tumour was clearly visualized in the images thus produced.

  1. Abducens nerve enhancement demonstrated by multiplanar reconstruction of contrast-enhanced three-dimensional MRI

    International Nuclear Information System (INIS)

    Hosoya, T.; Adachi, M.; Sugai, Y.; Yamaguchi, K.; Yamaguchi, K.; Kato, T.

    2001-01-01

    We describe contrast enhancement of the cisternal portion of the abducens nerve and discuss its clinical significance. We examined 67 patients with ophthalmoplegia using contrast-enhanced 3-dimensional (3D) MRI with multiplanar reconstruction along the nerves and found 16 patients (ten men, six women), aged 10-73 years (mean 34.4 years), with contrast enhancement of the abducens nerve. Of the 36 patients who had an abducens palsy, 14 (39 %) showed contrast enhancement. In the 16 patients, 23 abducens nerves enhanced; 13 were symptomatic and 10 asymptomatic at the time. The causes were disseminated tumour (1), an inflammatory process (3), trauma (2), ischaemia (2) and autoimmune diseases (8), such as the Miller Fisher syndrome, acute ophthalmoparesis, polyneuropathy and multiple sclerosis. Abducens and/or oculomotor nerve enhancement was the only abnormality on MRI in the patients with traumatic or ischaemic neuropathy or autoimmune diseases. There were 14 patients who recovered fully within 1-6 months after treatment, and resolution of the enhancement correlated well with recovery. (orig.)

  2. Improved wrist pannus volume measurement from contrast-enhanced MRI in rheumatoid arthritis using shuffle transform.

    Science.gov (United States)

    Xanthopoulos, Emily; Hutchinson, Charles E; Adams, Judith E; Bruce, Ian N; Nash, Anthony F P; Holmes, Andrew P; Taylor, Christopher J; Waterton, John C

    2007-01-01

    Contrast-enhanced MRI is of value in assessing rheumatoid pannus in the hand, but the images are not always easy to quantitate. To develop and evaluate an improved measurement of volume of enhancing pannus (VEP) in the hand in human rheumatoid arthritis (RA). MR images of the hand and wrist were obtained for 14 patients with RA at 0, 1 and 13 weeks. Volume of enhancing pannus was measured on images created by subtracting precontrast T1-weighted images from contrast-enhanced T1-weighted images using a shuffle transformation technique. Maximum intensity projection (MIP) and 3D volume rendering of the images were used as a guide to identify the pannus and any contrast-enhanced veins. Visualisation of pannus was much improved following the shuffle transform. Between 0 weeks and 1 week, the mean value of the within-subject coefficient of variation (CoV) was 0.13 and the estimated total CoV was 0.15. There was no evidence of significant increased variability within the 13-week interval for the complete sample of patients. Volume of enhancing pannus can be measured reproducibly in the rheumatoid hand using 3D contrast-enhanced MRI and shuffle transform.

  3. Breast dynamic contrast enhanced MRI: fibrocystic changes presenting as a non-mass enhancement mimicking malignancy

    Directory of Open Access Journals (Sweden)

    Milosevic Zorica C.

    2017-06-01

    Full Text Available We aimed to analyse the morphokinetic features of breast fibrocystic changes (nonproliferative lesions, proliferative lesions without atypia and proliferative lesions with atypia presenting as a non-mass enhancement (NMEin dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI examination.

  4. Evaluating automated dynamic contrast enhanced wrist 3T MRI in healthy volunteers

    DEFF Research Database (Denmark)

    Rastogi, Anshul; Kubassova, Olga; Krasnosselskaia, Lada V

    2013-01-01

    Dynamic contrast enhanced (DCE)-MRI has great potential to provide quantitative measure of inflammatory activity in rheumatoid arthritis. There is no current benchmark to establish the stability of signal in the joints of healthy subjects when imaged with DCE-MRI longitudinally, which is crucial so...

  5. Dynamics of contrast enhancement in MR imaging and power Doppler ultrasonography of solid breast lesions

    International Nuclear Information System (INIS)

    Reinikainen, H.; Paeaekkoe, E.; Suramo, I.; Paeivaensalo, M.; Rissanen, T.

    2002-01-01

    Purpose: To evaluate the dynamics of contrast enhancement in solid breast lesions at contrast-enhanced MR imaging and power Doppler ultrasonography (US) and to compare the methods to histology and to each other. Material and Methods: Forty breast lesions were prospectively examined with dynamic MR and power Doppler US. Time-signal intensity curves of enhancement were obtained for both methods. The shape of the curve was analyzed to be benign, indeterminate or malignant. The curves were also analyzed quantitatively by calculating the slope of the curve and the area under the curve (both methods), relative enhancement (MR), and time to peak (US). The lesions were divided into malignant lesions, fibroadenomas, and other benign lesions. The results were compared to histology. Results: In the subjective analysis of the MR curve in differentiating between benign and malignant lesions the accuracy was 90%. The MR curve also enabled differentiation between fibroadenomas and malignancies. The accuracy of the US curve was 38%. Quantitatively, statistically significant differences were found using all the MR variables, except between malignancies and fibroadenomas. Using the US variables, no significant difference was found between the groups. Conclusion: The dynamics of contrast-enhanced MR were reliable in the differential diagnosis of solid breast lesions, but contrast-enhanced power Doppler US was of limited value

  6. Data driven analysis of dynamic contrast-enhanced magnetic resonance imaging data in breast cancer diagnosis

    NARCIS (Netherlands)

    Twellmann, T.

    2005-01-01

    In the European Union, breast cancer is the most common type of cancer affecting women. If diagnosed in an early stage, breast cancer has an encouraging cure rate. Thus, early detection of breast cancer continues to be the key for an effective treatment. Recently, Dynamic Contrast-Enhanced Magnetic

  7. Medical Image Visual Appearance Improvement Using Bihistogram Bezier Curve Contrast Enhancement: Data from the Osteoarthritis Initiative

    Directory of Open Access Journals (Sweden)

    Hong-Seng Gan

    2014-01-01

    Full Text Available Well-defined image can assist user to identify region of interest during segmentation. However, complex medical image is usually characterized by poor tissue contrast and low background luminance. The contrast improvement can lift image visual quality, but the fundamental contrast enhancement methods often overlook the sudden jump problem. In this work, the proposed bihistogram Bezier curve contrast enhancement introduces the concept of “adequate contrast enhancement” to overcome sudden jump problem in knee magnetic resonance image. Since every image produces its own intensity distribution, the adequate contrast enhancement checks on the image’s maximum intensity distortion and uses intensity discrepancy reduction to generate Bezier transform curve. The proposed method improves tissue contrast and preserves pertinent knee features without compromising natural image appearance. Besides, statistical results from Fisher’s Least Significant Difference test and the Duncan test have consistently indicated that the proposed method outperforms fundamental contrast enhancement methods to exalt image visual quality. As the study is limited to relatively small image database, future works will include a larger dataset with osteoarthritic images to assess the clinical effectiveness of the proposed method to facilitate the image inspection.

  8. Contrast enhancement by lipid-based MRI contrast agents in mouse atherosclerotic plaques; a longitudinal study

    NARCIS (Netherlands)

    den Adel, Brigit; van der Graaf, Linda M.; Que, Ivo; Strijkers, Gustav J.; Löwik, Clemens W.; Poelmann, Robert E.; van der Weerd, Louise

    2013-01-01

    The use of contrast-enhanced MRI to enable in vivo specific characterization of atherosclerotic plaques is increasing. In this study the intrinsic ability of two differently sized gadolinium-based contrast agents to enhance atherosclerotic plaques in ApoE(-/-) mice was evaluated with MRI. We

  9. Avascular necrosis of femoral head: findings of contrast-enhanced MR imaging

    International Nuclear Information System (INIS)

    Shin, Yong Moon; Kang, Heung Sik; Kim, Chu Wan; Kim, Hee Joong; Kim, Young Min

    1995-01-01

    To evaluate the findings and the role of contrast enhanced magnetic resonance imaging in avascular necrosis of femoral head. Sixteen patients with avascular necorsis of femoral head were examined with MRI. T1-weighted and T2-weighted image and contrast-enhanced T1-weighted images were obtained. Enhancing characteristics of the necrotic area and synovium were determined. Also a change of the disease extent after enhancement was assessed. Twenty seven avascular necrosis of the femoral head including 11 cases of bilateral lesion were detected. Fifteen cases revealed collapse of the femoral head. The portions of the lesion with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images showed contrast enhancement in 15 cases. However, the potions with low signal intensities both on T1 and T2-weighted images showed enhancement in one case. There was no significant change of the disease extent after enhancement. Synovium showed enhancement in 18 cases, and joint effusion was detected in 23 cases. Contrast enhanced MR images may be helpful in predicting histopathologic findings of avascular necrosis of the femoral head, but not useful for evaluating the extent of disease

  10. Avascular necrosis of femoral head: findings of contrast-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Yong Moon; Kang, Heung Sik; Kim, Chu Wan; Kim, Hee Joong; Kim, Young Min [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1995-06-15

    To evaluate the findings and the role of contrast enhanced magnetic resonance imaging in avascular necrosis of femoral head. Sixteen patients with avascular necorsis of femoral head were examined with MRI. T1-weighted and T2-weighted image and contrast-enhanced T1-weighted images were obtained. Enhancing characteristics of the necrotic area and synovium were determined. Also a change of the disease extent after enhancement was assessed. Twenty seven avascular necrosis of the femoral head including 11 cases of bilateral lesion were detected. Fifteen cases revealed collapse of the femoral head. The portions of the lesion with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images showed contrast enhancement in 15 cases. However, the potions with low signal intensities both on T1 and T2-weighted images showed enhancement in one case. There was no significant change of the disease extent after enhancement. Synovium showed enhancement in 18 cases, and joint effusion was detected in 23 cases. Contrast enhanced MR images may be helpful in predicting histopathologic findings of avascular necrosis of the femoral head, but not useful for evaluating the extent of disease.

  11. Contrast enhanced digital mammography: Is it useful in detecting lesions in edematous breast?

    Directory of Open Access Journals (Sweden)

    Noha Abd ElShafy ElSaid

    2015-09-01

    Conclusion: Dual-energy contrast-enhanced digital mammography is a useful technique in identification of lesions in mammographically dense edematous breasts and proved to be a useful tool in the follow-up of cases presenting by edema after conservative breast surgery and chemotherapy.

  12. Renal perfusion scintiscan

    Science.gov (United States)

    ... Radionuclide renal perfusion scan; Perfusion scintiscan - renal; Scintiscan - renal perfusion Images Kidney anatomy Kidney - blood and urine flow Intravenous pyelogram References Rottenberg G, Andi AC. Renal ...

  13. Non-contrast enhanced magnetic resonance angiography techniques in candidates for kidney transplantation: A comparative study

    International Nuclear Information System (INIS)

    Blankholm, Anne Dorte; Ginnerup-Pedersen, Bodil; Stausbøl-Grøn, Brian; Haislund, Margit; Laustsen, Sussie; Ringgaard, Steffen

    2013-01-01

    Aim: Detailed knowledge of vessel status in potential candidates for kidney transplantation is essential for the surgeon. Contrast enhanced magnetic resonance angiography has previously been used intensively for assessing this, but the discovery that use of gadolinium based contrast agents in magnetic resonance imaging can cause Nephrogenic Systemic Fibrosis in patients suffering from severe kidney disease has lead to renewed interest in non-contrast enhanced magnetic resonance angiography. The aim of this study was to find a non-contrast enhanced magnetic resonance angiography method for preoperative evaluation of the pelvic vessels prior to kidney transplantation, providing a sufficient image quality. Method: In a prospective study we consecutively included 54 patients undergoing examinations prior to kidney transplantation. The patients were examined with the following magnetic resonance angiography sequences: A 2D Time of flight (n = 54), 3D Time of flight (n = 52) patients, 3D Phase Contrast (n = 54), 3D Balanced Steady State Free Precession (n = 52) and a 2D TRiggered Angiography Non-Contrast Enhanced (TRANCE) (a Spin Echo sequence with subtraction) (n = 48). The sequences were evaluated with respect to contrast, diagnostic performance and artefact burden. Results: Evaluating contrast, 3D Phase Contrast was significantly better than 2D Time of flight (p 0.2). The 2D Time of flight was significantly better than the other sequences (p < 0.001) in all cases. The artefact score was lowest for the Phase Contrast images and significantly superior to the 2D Time of flight (p < 0.005). The 2D Time of flight was significantly better than the three other sequences (p < 0.001) in all cases. Conclusion: Non-contrast enhanced magnetic resonance angiography offers a safe preoperative examination for assessment of vessel status before kidney transplantation. A combination of 2D Time of flight and 3D Phase Contrast acquisitions is recommended and can be performed within a

  14. Contrast-enhanced MR imaging of the endolymphatic sac in patients with sudden hearing loss

    International Nuclear Information System (INIS)

    Naganawa, Shinji; Koshikawa, Tokiko; Fukatsu, Hiroshi; Ishigaki, Takeo; Nakashima, Tsutomu; Ichinose, Nobuyasu

    2002-01-01

    Our objective was to evaluate the frequency of contrast enhancement of the endolymphatic sac in patients with sudden hearing loss. Forty consecutive patients with sudden sensorineural hearing loss (20 males and 20 females; age range 11-82 years), 40 age-matched control subjects, and 5 patients with Meniere's disease were examined using the same imaging protocol on a 1.5-T MR system. Pre- and post-contrast-enhanced T1-weighted 3D spoiled gradient-echo sequence (3D SPGR; TR/TE=23/10 ms, no. of excitations=1, flip angle=30 ) images were obtained using a voxel size of 0.6 x 0.7 x 0.8 mm 3 . Contrast enhancement in the area of the endolymphatic sac was assessed by two radiologists, and the frequency of contrast enhancement was compared between the three study groups. Enhancement of the ipsilateral endolymphatic sac was observed in 30 of the 40 patients with sudden hearing loss (75%). Twenty of these 30 patients also showed enhancement on the contralateral side, and 1 patient showed enhancement only on the contralateral side. Only 1 of the 5 patients with Meniere's disease showed enhancement. Nine of the 40 control subjects (22.5%) showed enhancement (bilateral enhancement in 5 subjects, unilateral in 4). The frequency of enhancement in patients with sudden hearing loss was significantly higher than that in control subjects (P<0.0001) or patients with Meniere's disease (P<0.05). The frequency of contrast enhancement of the endolymphatic sac is significantly increased in patients with sudden hearing loss, but further study is necessary to clarify the relationship between this finding and the pathophysiology of sudden hearing loss. (orig.)

  15. Contrast-enhanced color Doppler US in breast cancer: Tumoral vascularity correlated with angiogenesis

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    Kim, Eun A; Yoon, Kwon Ha; Yun, Ki Jung; Lee, Kwang Man; Park, Ki Han; Juhng, Seon Kwan; Won, Jong Jin [Wonkwang University School of Medicine, Seoul (Korea, Republic of)

    2000-12-15

    To evaluate the effects of contrast-enhanced color Doppler ultrasonography (CDUS) on the depiction of vascularity and flow pattern in breast cancer and to determine the relationship between tumoral vascularity and angiogenesis. Twenty-one patients with breast cancer were prospectively evaluated with CDUS before and after injection of the contrast agent (SH U 508A, 2.5g, 300 mg/ml ). The tumoral vascularity was expressed as percentage of color Doppler area, which was measured quantitatively by a computerized program (Ultrasonic Imaging Tool; Soongsil University, Seoul, Korea). The flow pattern (four-patterns; spotty, linear, branching, marginal) of the vascularity was analyzed. After surgery, tumor angiogenesis was assessed by microvessel density. The relationship between the vascularity on CDUS and microvessel density was statistically analyzed. At unenhanced CDUS, tumoral flow signals were detected in 12 lesions (48%); at contrast-enhanced CDUS, 18 lesions (86%). All These 18 lesions showed increased signals, compared with those at unenhanced CDUS. The percentage color Doppler area was 1.86 {+-} 0.48% at unenhanced CDUS and 5.23 {+-} 1.18% at contrast-enhanced CDUS. The flow patterns before contrast injection were spotty pattern in 11 tumors and linear pattern in one; after contrast injection, spotty in 8, linear in 4, branching in 5, and marginal in one. The tumoral vascularity at contrast-enhanced CDUS showed no significant correlation with microvessel density. Contrast-enhanced CDUS seems to be a valuable tool in the depiction of vascularity and characterization of flow pattern in breast cancer. However, tumoral vascularity on CDUS may not reflect tumoral angiogenesis.

  16. The value of contrast-enhanced CT scan in prediction of development of contusional hemorrhage

    International Nuclear Information System (INIS)

    Yokoyama, Kazuhiro; Kyoi, Kikuo; Sakaki, Toshisuke; Kinugawa, Kazuhiko; Morimoto, Tetsuya

    1983-01-01

    It is often experienced that even if there are no significant findings on the initial plain CT scan in the patient with cerebral contusion, the patient has thereafter a serious clinical course and requires emergency operation for so-called contusional hemorrhage. In order to predict of the development of contusional hemorrhage we performed contrast-enhanced CT scan at the time of patient's arrival within 12 hours after injury, if there was cerebral contusion on the initial plain CT scan, and repeated plain CT scan 24 hours after the contrast-enhanced CT scan. If enhancement was demonstrated on the contrastenhanced CT scan, we predicted the development of contusional hemorrhage and if not demonstrated, we predicted no more development of contusional hemorrhage and then we studied the correlation between the prediction and the plain CT 24 hours after the contrast-enhanced CT scan. The results were as follows: 1) The prediction was correct in 13 cases out of 16 cases in which the development of contusional hemorrhage was observed. In 18 cases where no development of contusional hemorrhage was observed, the prediction was correct without exception. 2) Most of the cases in which enhancement was demonstrated were ones examined not before 3 hours after injury. 3) The extent of enhancement shown on contrastenhanced CT scan was well consistent with that of contusional hemorrhage on the plain CT scan 24 hours after the contrast-enhanced CT scan. From these results, the contrast-enhanced CT scan in acute stage of head injury was considered to by very useful in prediction of the development of contusional hemorrhage. (author)

  17. Vascular patterns in nodules of intraductal papillary mucinous neoplasms depicted under contrast-enhanced ultrasonography are helpful for evaluating malignant potential

    International Nuclear Information System (INIS)

    Kurihara, Naoko; Kawamoto, Hirofumi; Kobayashi, Yoshiyuki; Okamoto, Yuko; Yamamoto, Naoki; Tsutsumi, Koichiro; Fujii, Masakuni; Kato, Hironari; Yamamoto, Kazuhide

    2012-01-01

    Objectives: The purpose of this study is to evaluate the feasibility of contrast-enhanced ultrasonography (CE-US) to differentiate between benign and malignant intraductal papillary mucinous neoplasms (IPMN). Patients and methods: Contrast-enhanced ultrasonography with a contrast agent was performed on 22 consecutive patients with IPMN suspected of being malignant. This revealed 10 carcinomas, 1 borderline lesion and 11 adenomas. All patients underwent surgery, and the histological diagnosis was confirmed by examination of resected specimens. CE-US was performed using a contrast agent. The detection rates of mural nodules were compared between CE-US and contrast-enhanced computed tomography (CE-CT), and the imaging of mural nodules depicted under CE-US was analyzed. Results: Seventeen of 22 resected specimens (77.3%) had mural nodules. There was no significant difference in the detection rate between CE-US (n = 15; 88.2%) and CE-CT (n = 12; 70.6%). In 12 (80.0%) of these patients, CE-US revealed small vessels in the mural nodule. The spotty or linear-shaped pattern was detected in 4 patients and the branch-shaped pattern in 8. The branch-shaped pattern lesion was associated with carcinoma. These mural nodules were 10 mm or more in height. In the perfusion image phase, cystic walls and mural nodules were also enhanced in all cases. Conclusion: The vessel shapes of the mural nodules depicted under CE-US were associated with size and pathological findings. These results suggested that CE-US with a contrast agent is a powerful modality with which to evaluate the malignant potential of IPMN.

  18. Assessment of contrast-enhanced ultrasonography of the hepatic vein for detection of hemodynamic changes associated with experimentally induced portal hypertension in dogs.

    Science.gov (United States)

    Morishita, Keitaro; Hiramoto, Akira; Michishita, Asuka; Takagi, Satoshi; Hoshino, Yuki; Itami, Takaharu; Lim, Sue Yee; Osuga, Tatsuyuki; Nakamura, Sayuri; Ochiai, Kenji; Nakamura, Kensuke; Ohta, Hiroshi; Yamasaki, Masahiro; Takiguchi, Mitsuyoshi

    2017-04-01

    OBJECTIVE To assess the use of contrast-enhanced ultrasonography (CEUS) of the hepatic vein for the detection of hemodynamic changes associated with experimentally induced portal hypertension in dogs. ANIMALS 6 healthy Beagles. PROCEDURES A prospective study was conducted. A catheter was surgically placed in the portal vein of each dog. Hypertension was induced by intraportal injection of microspheres (10 to 15 mg/kg) at 5-day intervals via the catheter. Microsphere injections were continued until multiple acquired portosystemic shunts were created. Portal vein pressure (PVP) was measured through the catheter. Contrast-enhanced ultrasonography was performed before and after establishment of hypertension. Time-intensity curves were generated from the region of interest in the hepatic vein. Perfusion variables measured for statistical analysis were hepatic vein arrival time, time to peak, time to peak phase (TTPP), and washout ratio. The correlation between CEUS variables and PVP was assessed by use of simple regression analysis. RESULTS Time to peak and TTPP were significantly less after induction of portal hypertension. Simple regression analysis revealed a significant negative correlation between TTPP and PVP. CONCLUSIONS AND CLINICAL RELEVANCE CEUS was useful for detecting hemodynamic changes associated with experimentally induced portal hypertension in dogs, which was characterized by a rapid increase in the intensity of the hepatic vein. Furthermore, TTPP, a time-dependent variable, provided useful complementary information for predicting portal hypertension. IMPACT FOR HUMAN MEDICINE Because the method described here induced presinusoidal portal hypertension, these results can be applied to idiopathic portal hypertension in humans.

  19. MRI and MRA of kidney transplants - evaluation of vessels and perfusion

    International Nuclear Information System (INIS)

    Wiesner, W.; Pfammatter, T.; Krestin, G.P.; Debatin, J.F.

    1998-01-01

    Purpose: To document the value of fast contrast enhanced-sequences in the assessment of the vascular supply and parenchymal perfusion in renal transplants. Patients: 18 recipients of a renal transplant were examined with a 1.5-Tesla-MR-system. The protocol included fast contrast enhanced 3D MR angiography and coronal 2D GRE sequences. The transplant artery and vein were assessed as well as regional parenchymal perfusion. Results: 3D MRA detected three transplant artery stenoses and one occlusion. In addition, two renal vein thromboses and one compression were identified. Perfusion deficits were documented in 8 renal transplants: Renal infarction (n=4), cortical necrosis (n=2), acute tubular necrosis (n=1) and venous ischemia (n=1). Fluid collections were documented as well as dilatation of the collecting system and abnormalities of the surrounding tissues. Conclusion: Contrast enhanced MRI and MRA permit a comprehensive assessment of renal transplants without inducing nephrotoxicity. (orig.) [de

  20. Quantitative perfusion imaging in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Zoellner, F.G.; Gaa, T.; Zimmer, F.; Ong, M.M.; Riffel, P.; Hausmann, D.; Schoenberg, S.O.; Weis, M.

    2016-01-01

    Magnetic resonance imaging (MRI) is recognized for its superior tissue contrast while being non-invasive and free of ionizing radiation. Due to the development of new scanner hardware and fast imaging techniques during the last decades, access to tissue and organ functions became possible. One of these functional imaging techniques is perfusion imaging with which tissue perfusion and capillary permeability can be determined from dynamic imaging data. Perfusion imaging by MRI can be performed by two approaches, arterial spin labeling (ASL) and dynamic contrast-enhanced (DCE) MRI. While the first method uses magnetically labelled water protons in arterial blood as an endogenous tracer, the latter involves the injection of a contrast agent, usually gadolinium (Gd), as a tracer for calculating hemodynamic parameters. Studies have demonstrated the potential of perfusion MRI for diagnostics and also for therapy monitoring. The utilization and application of perfusion MRI are still restricted to specialized centers, such as university hospitals. A broad application of the technique has not yet been implemented. The MRI perfusion technique is a valuable tool that might come broadly available after implementation of standards on European and international levels. Such efforts are being promoted by the respective professional bodies. (orig.) [de

  1. Contrast-enhanced MR 3D angiography in the assessment of brain AVMs

    International Nuclear Information System (INIS)

    Unlu, Ercument; Temizoz, Osman; Albayram, Sait; Genchellac, Hakan; Hamamcioglu, M. Kemal; Kurt, Imran; Demir, M. Kemal

    2006-01-01

    Background and purpose: Digital subtraction angiography (DSA) is the current reference standard for the diagnosis, assessment, and management of brain arteriovenous malformations (AVMs). The purpose of this study was to compare the diagnostic utility of three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and contrast-enhanced 3D MRA in patients with intracranial arteriovenous malformations (AVMs) in different sizes and locations. The AVM diagnosis was proved via DSA and almost half of the patients had also hematoma. Materials and methods: Two radiologists, experienced on neurovascular imaging and independent from each other, retrospectively reviewed two MRA techniques and DSA with regard to the assessment of feeding arteries, AVM nidus, and venous drainage patterns on 20 patients with 23 examinations by scoring system. Disagreements were resolved by consensus. Results: An excellent agreement between contrast-enhanced MRA and DSA was found in order to assess the numbers of arterial feeders and draining veins (Spearman r = 0.913, P < 0.001). The average scores in contrast-enhanced MRA for feeders, nidi, and drainers were respectively 2.26, 2.69, and 2.48, while in TOF-MRA they are 1.96, 1.35, and 0.89, respectively. Conclusion: Compared to TOF-MRA, 3D contrast-enhanced MRA is useful for visualization by subtraction technique of malformation components presented by hematoma or by haem product. On the other hand, for the cases presented by slow or complex flow that is especially in around or nidi or around the venous portion is also advantageous because of the independence from flow-related enhancement. Therapeutic effects were clearly demonstrated in three follow-up patients. A major limitation of this technique is the low spatial resolution. Since there is such a limitation, arterial feeder of a case with micro-AVM is not detected by contrast-enhanced MRA and nidus for the same case was observed retrospectively. In this respect, we

  2. Contrast-enhanced MR 3D angiography in the assessment of brain AVMs

    Energy Technology Data Exchange (ETDEWEB)

    Unlu, Ercument [Department of Radiology, Trakya University Medicine School, Edirne (Turkey)]. E-mail: drercument@yahoo.com; Temizoz, Osman [Department of Radiology, Trakya University Medicine School, Edirne (Turkey); Albayram, Sait [Department of Radiology, Istanbul University, Cerrahpasa Medicine School, Istanbul (Turkey); Genchellac, Hakan [Department of Radiology, Trakya University Medicine School, Edirne (Turkey); Hamamcioglu, M. Kemal [Department of Neurosurgery, Trakya University Medicine School, Edirne (Turkey); Kurt, Imran [Department of Biostatistics, Trakya University Medicine School, Edirne (Turkey); Demir, M. Kemal [Department of Radiology, Trakya University Medicine School, Edirne (Turkey)

    2006-12-15

    Background and purpose: Digital subtraction angiography (DSA) is the current reference standard for the diagnosis, assessment, and management of brain arteriovenous malformations (AVMs). The purpose of this study was to compare the diagnostic utility of three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and contrast-enhanced 3D MRA in patients with intracranial arteriovenous malformations (AVMs) in different sizes and locations. The AVM diagnosis was proved via DSA and almost half of the patients had also hematoma. Materials and methods: Two radiologists, experienced on neurovascular imaging and independent from each other, retrospectively reviewed two MRA techniques and DSA with regard to the assessment of feeding arteries, AVM nidus, and venous drainage patterns on 20 patients with 23 examinations by scoring system. Disagreements were resolved by consensus. Results: An excellent agreement between contrast-enhanced MRA and DSA was found in order to assess the numbers of arterial feeders and draining veins (Spearman r = 0.913, P < 0.001). The average scores in contrast-enhanced MRA for feeders, nidi, and drainers were respectively 2.26, 2.69, and 2.48, while in TOF-MRA they are 1.96, 1.35, and 0.89, respectively. Conclusion: Compared to TOF-MRA, 3D contrast-enhanced MRA is useful for visualization by subtraction technique of malformation components presented by hematoma or by haem product. On the other hand, for the cases presented by slow or complex flow that is especially in around or nidi or around the venous portion is also advantageous because of the independence from flow-related enhancement. Therapeutic effects were clearly demonstrated in three follow-up patients. A major limitation of this technique is the low spatial resolution. Since there is such a limitation, arterial feeder of a case with micro-AVM is not detected by contrast-enhanced MRA and nidus for the same case was observed retrospectively. In this respect, we

  3. Angiogenesis and dynamic contrast enhanced MRI of benign and malignant breast lesions: preliminary results

    International Nuclear Information System (INIS)

    Liu Peifang; Bao Runxian; Niu Yun; Yu Yong

    2002-01-01

    Objective: To determine whether dynamic contrast enhanced MRI features of early-phase enhancement rate, enhancement amplitude, and signal intensity (SI) time course are associated with the microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression of malignant and benign breast lesions. Methods: Thirty-eight patients with histopathologically verified breast lesions underwent dynamic contrast enhanced MRI. SI changes during dynamic scanning were assessed quantitatively. Early-phase enhancement rate and enhancement amplitude were calculated. Time-SI curves of the lesions were obtained and classified according to their shapes as type I (which was steady enhancement to the end of the dynamic data acquisition at 7.5 min), type II (plateau of SI after avid initial contrast enhancement), or type III (washout of SI after avid initial contrast enhancement). the mean MVD and VEGF expression of the lesions were measured with immuno-histochemical staining method in all the histologic specimens by pathologists without the knowledge of the results of the MR examination. The relationships among dynamic contrast enhanced MRI features, MVD, and VEGF expression of benign and malignant breast lesions were analyzed. Results: Histology revealed 21 malignancies and 17 benign lesions. The mean MVD and VEGF expression for 21 malignant lesions were statistically higher than the mean MVD and VEGF expression for 17 benign lesions. High VEGF expression of benign and malignant breast lesions showed an association with increased MVD. Among all 38 lesions, greater (> 60%) MR early-phase enhancement rate and time-SI curve type II and III showed an association with increased MVD and higher VEGF expression level. All the differences mentioned above showed statistical significance except that the difference between VEGF expression and the distribution of curve types had no statistical significance. No significant relationships were observed between the mean of enhancement

  4. Evaluation on changes of early renal function in patients with diabetic nephropathy with contrast-enhanced ultrasound and its clinical significance

    International Nuclear Information System (INIS)

    Guo Xinmin; Jin Hong; Pan Liwen; Chen Hui; Liu Wei; Quan Xianyue

    2013-01-01

    Objective: To quantitatively assess the parameter alteration of renal blood flow in patients with diabetic nephropathy (DN) with the contrast-enhanced ultrasound (CEUS), and to evaluate value of the technique in diagnosis of early renal function changes of DN patients. Methods: 40 diabetic patients were equally divided into two group according to Mogensen's staging criteria: normal albuminuria group (group Ⅰ) and early DN group (group Ⅱ); and 15 cases of healthy volunteers were used as control group (N group) (n=15). All subjects were performed renal CEUS perfusion imaging, and QontraXt image analysis software was applied to select the region of interest (ROI) in the renal cortex. Then the time intensity curve (TIC) and kidney blood perfusion parameters were collected. Results: The renal blood perfusion was clearly shown in real time CEUS; compared with N group, the time to peak (TTP), regional blood volume (RBV), and mean transit time (MTT) of the patients in group Ⅰ were increased, there were significant differences (P<0.05); but there were no significant differences of derived peak intensity (DPI) and regional blood flow (RBF) between two groups (P>0.05). Compared with group Ⅰ and N group, the RBV, TTP and MTT of the patients were increased, the DPI and RBF were reduced in group Ⅱ, there were significant differences (P<0.05). Conclusion: The CEUS technical analysis can be used in evaluating renal abnormality of the DN patients in early period by showing the changes of renal perfusion parameters. (authors)

  5. 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.

  6. Comparison of neuroendocrine tumor detection and characterization using DOTATOC-PET in correlation with contrast enhanced CT and delayed contrast enhanced MRI

    International Nuclear Information System (INIS)

    Giesel, F.L.; Kratochwil, C.; Mehndiratta, A.; Wulfert, S.; Moltz, J.H.; Zechmann, C.M.; Kauczor, H.U.; Haberkorn, U.; Ley, S.

    2012-01-01

    Purpose: We evaluated the rate of successful characterization of gastroenteropancreatic neuroendocrine tumors (NETs) present with an increased somatostatin receptor, comparing CE-CT with CE-MRI, each in correlation with DOTATOC-PET. Methods and materials: 8 patients with GEP-NET were imaged using CE-MRI (Gd-EOB-DTPA), CE-CT (Imeron 400) and DOTATOC-PET. Contrast-enhancement of normal liver-tissue and metastasis was quantified with ROI-technique. Tumor delineation was assessed with visual-score in blind-read-analysis by two experienced radiologists. Results: Out of 40 liver metastases in patients with NETs, all were detected by CE-MRI and the lesion extent could be adequately assessed, whereas CT failed to detect 20% of all metastases. The blind-read-score of CT in arterial and portal phase was median −0.65 and −1.4, respectively, and 2.7 for delayed-MRI. The quantitative ROI-analysis presented an improved contrast-enhancement-ratio with a median of 1.2, 1.6 and 3.3 for CE-CT arterial, portal-phase and delayed-MRI respectively. Conclusion: Late CE-MRI was superior to CE-CT in providing additionally morphologic characterization and exact lesion extension of hepatic metastases from neuroendocrine tumor detected with DOTATOC-PET. Therefore, late enhanced Gd-EOB-DTPA-MRI seems to be the adequate imaging modality for combination with DOTATOC-PET to provide complementary (macroscopic and molecular) tumor characterization in hepatic metastasized NETs

  7. Comparison of gray-scale contrast-enhanced ultrasonography with contrast-enhanced computed tomography in different grading of blunt hepatic and splenic trauma: an animal experiment.

    Science.gov (United States)

    Tang, Jie; Li, Wenxiu; Lv, Faqin; Zhang, Huiqin; Zhang, Lihai; Wang, Yuexiang; Li, Junlai; Yang, Li

    2009-04-01

    To compare the diagnostic value of contrast-enhanced ultrasonography (CEUS) with contrast-enhanced computed tomography (CECT) for the detection of different grading of solid organ injuries in blunt abdominal trauma in animals. A self-made miniature tools were used as models to simulate a blunt hepatic or splenic trauma in 16 and 14 anesthetized dogs, respectively. Baseline ultrasound, CEUS and CECT were used to detect traumatic injuries of livers and spleens. The degree of injuries was determined by CEUS according to the American Association for the Surgery of Trauma (AAST) scale and the results compared with injury scale based on CECT evaluation. CEUS showed 22 hepatic injury sites in 16 animals and 17 splenic injury sites in other 14 animals. According to AAST scale, 2 grade I, 4 grade II, 3 grade III, 5 grade IV and 2 grade V hepatic lesions were present in 16 animals; 2 grade I, 4 grade II, 6 grade III and 2 grade IV splenic lesions in 14 animals. On CECT scan, 21 hepatic and 17 splenic injuries were demonstrated. According to Becker CT scaling for hepatic injury, 1 grade I, 2 grade II, 4 grade III, 5 grade IV and 2 grade V hepatic injuries were present. On the basis of Buntain spleen scaling, 2 grade I, 5 grade II, 5 grade III, 2 grade IV splenic injuries were showed. After Spearman rank correlation analysis, the agreement of CEUS with CECT on the degree of hepatic and splenic injury is 93.3% and 92.9%, respectively. CT is currently considered as the reference method for grading blunt abdominal trauma, according to experiment results, CEUS grading showed high levels of concordance with CECT. CEUS can accurately determine the degree of injury and will play an important role in clinical application.

  8. Advanced ultrasound applications in the assessment of renal transplants: contrast-enhanced ultrasound, elastography, and B-flow.

    Science.gov (United States)

    Morgan, Tara A; Jha, Priyanka; Poder, Liina; Weinstein, Stefanie

    2018-04-09

    Ultrasound is routinely used as the first imaging exam for evaluation of renal transplants and can identify most major surgical complications and evaluate vascularity with color Doppler. Ultrasound is limited, however, in the detection of parenchymal disease processes and Doppler evaluation is also prone to technical errors. Multiple new ultrasound applications have been developed and are under ongoing investigation which could add additional diagnostic capability to the routine ultrasound exam with minimal additional time, cost, and patient risk. Contrast-enhanced ultrasound (CEUS) can be used off-label in the transplant kidney, and can assist in detection of infection, trauma, and vascular complications. CEUS also can demonstrate perfusion of the transplant assessed quantitatively with generation of time-intensity curves. Future directions of CEUS include monitoring treatment response and microbubble targeted medication delivery. Elastography is an ultrasound application that can detect changes in tissue elasticity, which is useful to diagnose diffuse parenchymal disease, such as fibrosis, otherwise unrecognizable with ultrasound. Elastography has been successfully applied in other organs including the liver, thyroid, and breast; however, it is still under development for use in the transplant kidney. Unique properties of the transplant kidney including its heterogeneity, anatomic location, and other technical factors present challenges in the development of reference standard measurements. Lastly, B-flow imaging is a flow application derived from B-mode. This application can show the true lumen size of a vessel which is useful to depict vascular anatomy and bypasses some of the pitfalls of color Doppler such as demonstration of slow flow.

  9. Quantitative contrast-enhanced ultrasound evaluation of pathological complete response in patients with locally advanced breast cancer receiving neoadjuvant chemotherapy.

    Science.gov (United States)

    Wan, Cai-Feng; Liu, Xue-Song; Wang, Lin; Zhang, Jie; Lu, Jin-Song; Li, Feng-Hua

    2018-06-01

    To clarify whether the quantitative parameters of contrast-enhanced ultrasound (CEUS) can be used to predict pathological complete response (pCR) in patients with locally advanced breast cancer receiving neoadjuvant chemotherapy (NAC). Fifty-one patients with histologically proved locally advanced breast cancer scheduled for NAC were enrolled. The quantitative data for CEUS and the tumor diameter were collected at baseline and before surgery, and compared with the pathological response. Multiple logistic regression analysis was performed to examine quantitative parameters at CEUS and the tumor diameter to predict the pCR, and receiver operating characteristic (ROC) curve analysis was used as a summary statistic. Multiple logistic regression analysis revealed that PEAK (the maximum intensity of the time-intensity curve during bolus transit), PEAK%, TTP% (time to peak), and diameter% were significant independent predictors of pCR, and the area under the ROC curve was 0.932(Az 1 ), and the sensitivity and specificity to predict pCR were 93.7% and 80.0%. The area under the ROC curve for the quantitative parameters was 0.927(Az 2 ), and the sensitivity and specificity to predict pCR were 81.2% and 94.3%. For diameter%, the area under the ROC curve was 0.786 (Az 3 ), and the sensitivity and specificity to predict pCR were 93.8% and 54.3%. The values of Az 1 and Az 2 were significantly higher than that of Az 3 (P = 0.027 and P = 0.034, respectively). However, there was no significant difference between the values of Az 1 and Az 2 (P = 0.825). Quantitative analysis of tumor blood perfusion with CEUS is superior to diameter% to predict pCR, and can be used as a functional technique to evaluate tumor response to NAC. Copyright © 2018. Published by Elsevier B.V.

  10. Repeatability and correlations of dynamic contrast enhanced and T2* MRI in patients with advanced pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Klaassen, Remy; Gurney-Champion, Oliver J; Wilmink, Johanna W; Besselink, Marc G; Engelbrecht, Marc R W; Stoker, Jaap; Nederveen, Aart J; van Laarhoven, Hanneke W M

    2018-07-01

    In current oncological practice of pancreatic ductal adenocarcinoma (PDAC), there is a great demand for response predictors and markers for early treatment evaluation. In this study, we investigated the repeatability and the interaction of dynamic contrast enhanced (DCE) and T2* MRI in patients with advanced PDAC to enable for such evaluation using these techniques. 15 PDAC patients underwent two DCE, T2* and anatomical 3 T MRI sessions before start of treatment. Parametric maps were calculated for the transfer constant (K trans ), rate constant (k ep ), extracellular extravascular space (v e ) and perfusion fraction (v p ). Quantitative R2* (1/T2*) maps were obtained from the multi-echo T2* images. Differences between normal and cancerous pancreas were determined using a Wilcoxon matched pairs test. Repeatability was obtained using Bland-Altman analysis and relations between DCE and T2*/R2* were observed by Spearman correlation and voxel-wise binned plots of tumor voxels. PDAC K trans (p = 0.007), k ep (p T2*. Voxel wise analysis showed a steep increase in R2* for tumor voxels with lower K trans and v e . We showed good repeatability of DCE and T2* related MRI parameters in advanced PDAC patients. Furthermore, we have illustrated the relation of DCE K trans and v e with tissue T2* and R2* indicating substantial value of these parameters for detecting tumor hypoxia in future studies. The results from our study pave the way for further response evaluation studies and patient selection based on DCE and T2* parameters. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. A review on brightness preserving contrast enhancement methods for digital image

    Science.gov (United States)

    Rahman, Md Arifur; Liu, Shilong; Li, Ruowei; Wu, Hongkun; Liu, San Chi; Jahan, Mahmuda Rawnak; Kwok, Ngaiming

    2018-04-01

    Image enhancement is an imperative step for many vision based applications. For image contrast enhancement, popular methods adopt the principle of spreading the captured intensities throughout the allowed dynamic range according to predefined distributions. However, these algorithms take little or no consideration into account of maintaining the mean brightness of the original scene, which is of paramount importance to carry the true scene illumination characteristics to the viewer. Though there have been significant amount of reviews on contrast enhancement methods published, updated review on overall brightness preserving image enhancement methods is still scarce. In this paper, a detailed survey is performed on those particular methods that specifically aims to maintain the overall scene illumination characteristics while enhancing the digital image.

  12. Contrast-enhanced CT and MRI findings of atypical hepatic Echinococcus alveolarisinfestation

    International Nuclear Information System (INIS)

    Etlik, Oemer; Arslan, Halil; Harman, Mustafa; Temizoez, Osman; Bay, Ali; Koesem, Mustafa; Dogan, Ekrem

    2005-01-01

    Diagnosis of liver infestation by Echinococcus alveolaris(EA) is based on serological and radiological findings. In this report, we present a 15-year-old girl with atypical hepatic EA infestation showing central punctate calcifications and contrast enhancement on the portal and late phases of CT and MRI. CT showed a hypodense mass involving more than half of the liver with prominent central calcifications. MRI revealed hypointense signal of the infiltrative mass on both T1- and T2-weighted images. Contrast enhancement is a unique finding in hepatic EA infestation that may cause difficulties with diagnosis. MRI may provide invaluable information in the diagnosis of EA infestation of the liver, either by disclosing the infiltrative pattern of infestation without significant effect to vascular structures, or by the signal characteristics. (orig.)

  13. Contrast-enhanced CT and MRI findings of atypical hepatic Echinococcus alveolarisinfestation

    Energy Technology Data Exchange (ETDEWEB)

    Etlik, Oemer; Arslan, Halil; Harman, Mustafa; Temizoez, Osman [Yuzuncu Yil University Faculty of Medicine, Department of Radiology, Van (Turkey); Bay, Ali [Yuzuncu Yil University Faculty of Medicine, Department of Paediatrics, Van (Turkey); Koesem, Mustafa [Yuzuncu Yil University Faculty of Medicine, Department of Pathology, Van (Turkey); Dogan, Ekrem [Yuzuncu Yil University Faculty of Medicine, Department of Internal Medicine, Van (Turkey)

    2005-05-01

    Diagnosis of liver infestation by Echinococcus alveolaris(EA) is based on serological and radiological findings. In this report, we present a 15-year-old girl with atypical hepatic EA infestation showing central punctate calcifications and contrast enhancement on the portal and late phases of CT and MRI. CT showed a hypodense mass involving more than half of the liver with prominent central calcifications. MRI revealed hypointense signal of the infiltrative mass on both T1- and T2-weighted images. Contrast enhancement is a unique finding in hepatic EA infestation that may cause difficulties with diagnosis. MRI may provide invaluable information in the diagnosis of EA infestation of the liver, either by disclosing the infiltrative pattern of infestation without significant effect to vascular structures, or by the signal characteristics. (orig.)

  14. Feature and Contrast Enhancement of Mammographic Image Based on Multiscale Analysis and Morphology

    Directory of Open Access Journals (Sweden)

    Shibin Wu

    2013-01-01

    Full Text Available A new algorithm for feature and contrast enhancement of mammographic images is proposed in this paper. The approach bases on multiscale transform and mathematical morphology. First of all, the Laplacian Gaussian pyramid operator is applied to transform the mammography into different scale subband images. In addition, the detail or high frequency subimages are equalized by contrast limited adaptive histogram equalization (CLAHE and low-pass subimages are processed by mathematical morphology. Finally, the enhanced image of feature and contrast is reconstructed from the Laplacian Gaussian pyramid coefficients modified at one or more levels by contrast limited adaptive histogram equalization and mathematical morphology, respectively. The enhanced image is processed by global nonlinear operator. The experimental results show that the presented algorithm is effective for feature and contrast enhancement of mammogram. The performance evaluation of the proposed algorithm is measured by contrast evaluation criterion for image, signal-noise-ratio (SNR, and contrast improvement index (CII.

  15. Local ablation therapy with contrast-enhanced ultrasonography for hepatocellular c