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Sample records for gd enhanced mri

  1. Gd enhanced MRI in sensorineural hearing loss

    International Nuclear Information System (INIS)

    Takenaka, Mika; Tono, Tetsuya; Toyama, Katsuhiro; Kano, Kiyo; Morimitsu, Tamotsu

    1996-01-01

    The enhanced MRI hearing findings of the inner ear in 124 patients with sensorineural hearing loss were evaluated. MR images were obtained before and after the intravenous administration of gadolinium (0.1 mmol/kg). In three out of seventy-nine patients with unilateral healing loss, cochlear and/or the vestibular enhancement was noted on the symptomatic side. The positive cases included those with Ramsay-Hunt syndrome, mumps and so-called sudden deafness. Forty-five patients with bilateral hearing loss showed no enhancement within the inner ear. Although positive gadolinium enhancement of the inner ear may detect inflammatory lesions due to a viral infection, its incidence in sensorineural hearing loss, including cases of sudden deafness. seems to be extremely rare. (author)

  2. A comparison of Gd-BOPTA and Gd-DOTA for contrast-enhanced MRI of intracranial tumours

    International Nuclear Information System (INIS)

    Colosimo, C.; Knopp, M.V.; Barreau, X.; Gerardin, E.; Kirchin, M.A.; Guezenoc, F.; Lodemann, K.P.

    2004-01-01

    A two-centre intra-individual crossover study was performed in 23 patients with suspected high-grade glioma or metastases to assess and compare the safety and enhancement characteristics of two different MRI contrast media (gadobenate dimeglumine, Gd-BOPTA and gadoterate meglumine, Gd-DOTA) at equivalent doses of 0.1 mmol/kg body weight. T1-weighted spin-echo (SE) and T2-weighted fast SE images were obtained before and T1-weighted images 0, 2, 4, 6, 8 and 15 min after injection. T1-weighted images with magnetisation transfer contrast were acquired 12 min after injection. Qualitative assessment by blinded, off-site readers (reader 1: 19 patients; reader 2: 21) and on-site investigators (23) revealed significant (P ≤0.005) overall preference for Gd-BOPTA over Gd-DOTA for contrast enhancement (Gd-BOPTA preferred in 18, 15 and 18 cases; Gd-DOTA in 0, 1 and 1 and no preference in 1, 5 and 4; off-site readers 1 and 2, and on-site investigators, respectively). A similar significant preference for Gd-BOPTA was expressed by off-site readers and on-site investigators for lesion-to-brain contrast, lesion delineation, internal lesion structure, and overall image preference. Quantitative assessment by off-site readers revealed significantly (p<0.05) greater lesion enhancement with Gd-BOPTA than with Gd-DOTA at all times from 2 min after injection. (orig.)

  3. Efficacy of Gd-DTPA-enhanced MRI in hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    Okamoto, Shinya; Aoki, Toshikazu; Konishi, Tokuji; Nakano, Takeshi; Yamakado, Kyoichiro; Sakuma, Hajime; Takeda, Kann; Nakagawa, Takashi

    1991-01-01

    The cabability of magnetic resonance (MR) imaging to detect tissue characterization or myocardial degeneration process of the hypertrophied myocardium was evaluated in 15 patients with hypertrophic cardiomyopathy. T1-weighted MR images were obtained with a 1.5 T MR unit by using ECG-gated spin-echo techniques. MR images were visually reviewed before and after enhancement of Gd-DTPA. Four patients had an increase in signal intensity mainly in the endocardium of the left ventricular septum on non-enhanced MR images, 3 of whom had widespread high intensity in addition to two-thirds of the wall. Gd-DTPA enhanced-MR images showed high intensity over the whole septum in 5 patients and also in the antero-lateral endocardium in 4 patients. Decreased intensity on non-enhanced MR images, as shown in 4 patients, became clear on enhanced-MR images. According to findings on enhanced-MR images, signal intensity was defined as normal (N), septum (S), and diffuse (D). Patients in Group D tended to be younger and have more frequently family history. Regarding both interventricular septum thickness and left ventricular posterior wall thickness, there was no significant difference among the three groups. Both left ventricular diastolic diameter and left ventricular systolic diameter were significantly larger in Group D than the other two groups. Left ventricular ejection fraction was significantly lower in both Group S and Group D. Widespread abnormal intensity on Gd-DTPA enhanced MR images was associated with findings similar to dilated cardiomyopathy, such as dilated left ventricular lumen and decreased ejection fraction. Gd-DTPA enhanced MR imaging seemed to be useful for visualizing myocardial degeneration in hypertrophic cardiomyopathy.(N.K.)

  4. Assessment of left ventricular hemodynamics by Gd-DTPA enhanced high speed cine MRI

    International Nuclear Information System (INIS)

    Matsumura, Kentaro; Nakase, Emiko; Kawai, Ichiro

    1992-01-01

    To assess the validity of Gd-DTPA enhanced high speed cine MRI in left ventricular (LV) volumes and ejection fraction (EF), high speed cine MRI was compared with intra-venous digital subtraction left ventriculography (IV-DSA) in 14 patients. All patients underwent conventional cine MRI and Gd-DTPA enhanced high speed MRI, simultaneously. The pulse sequences of high speed MRI were TR 8 ms (TR 6 ms plus rewind pulse 2 ms), TE 3.2 ms, matrix 128, phase encode 8 or 6 and NEX 1. Comparison with LV-volume showed a high correlation (y = 0.854x + 1,699, r = 0.985) between high speed cine MRI and VI-DSA. To make left ventricular volume curve by area-length method in cine MRI, manual tracing of LV-cavity was more difficult in conventional cine MRI-method than enhanced high speed cine MRI-method. In conclusion, first pass-Gd-DTPA enhanced high speed cine MRI, using the horizontal long axis approach and the multiphase study, is a highly, accurate reproducible method of evaluating LV-volumetry. (author)

  5. Gd(III)-nanodiamond conjugates for MRI contrast enhancement

    Science.gov (United States)

    Manus, Lisa M.; Mastarone, Daniel J.; Waters, Emily A.; Zhang, Xue-Qing; Schultz-Sikma, Elise A.; MacRenaris, Keith W.; Ho, Dean

    2010-01-01

    A Gd(III)-nanodiamond conjugate [Gd(III)-ND] was prepared and characterized, enabling detection of nanodiamonds by MR imaging. The Gd(III)-ND particles significantly reduced the T1 of water protons with a per-Gd(III) relaxivity of 58.82 ± 1.18 mM−1s−1 at 1.5 Tesla (60 MHz). This represents a tenfold increase compared to the monomer Gd(III) complex (r1 = 5.42 ± 0.20 mM−1s−1) and is among the highest per-Gd(III) relaxivities reported. PMID:20038088

  6. Gd-DTPA enhanced MRI of the brain infarction: correlation between onset of infarction and enhancing patterns

    International Nuclear Information System (INIS)

    Joo, An Young; Kim, Myung Soon; Lee, Sung Soo

    1994-01-01

    To evaluate the correlation between onset of brain infarction and Gd-DTPA enhancing patterns on MRI. We reviewed MRI of 58 lesions in 45 patients with clinically documented brain infarction retrospectively. Axial, coronal and sagittal T1WI (TR/TE 450-520/20), T2WI (TR/TE 2190/90) and Gd-DTPA enhanced T1WI were performed with a 0.5T superconductive MR system. We analyzed Gd-enhancing patterns that were divided into intravascular, meningeal, and parenchymal enhancement. Parenchymal pattern was subdivided into mottled, partial ring like and dense enhancement. Intravascular enhancement was seen at 1-10 days in 30(53%) of 58 infarctions. Meningeal enhancement (13%) was noted at 1-6 days. Parenchymal enhancement (50%) was seen at 2-28 days and subdividing patterns are as follows: The mottled enhancement pattern was seen earlier at 2-8 days and partial ring like or dense enhancement patterns at 5-28 days. After reviewing Gd-enhanced MRI of infarction, the intravascular and meningeal enhancement patterns were earlier than parenchymal enhancement. Among parenchymal patterns, the mottled pattern was seen earlier than partial ring like or dense patterns. In conclusion, Gd-enhancing patterns of brain infarction are useful in estimating the age of infarction including acute infarction

  7. Transudative vs exudative pleural effusions: differentiation using Gd-DTPA-enhanced MRI

    International Nuclear Information System (INIS)

    Frola, C.; Cantoni, S.; Turtulici, I.; Leoni, C.; Loria, F.; Gaeta, M.; Derchi, L.E.

    1997-01-01

    The aim of this study was to investigate the capability of Gd-DTPA-enhanced MRI to differentiate between exudative and transudative pleural effusions. An MRI examination was performed on 22 patients with different types of pleural effusion (10 transudative and 12 exudative effusions). T1-weighted SE images were obtained before and 20 min after administration of Gd-DTPA (0.1 mmol/kg). The degree of enhancement of pleural effusions was evaluated both by visual assessement and by quantitative analysis of images. None of 10 transudative effusions showed significative enhancement, whereas 10 of 12 exudative effusions showed enhancement (sensitivity 83 %, specificity 100 %, positive predictive value 100 %). The postcontrast signal intensity ratios (SIRs) of exudates were significantly higher than corresponding precontrast ratios (P = 0.0109) and the postcontrast SIRs of exudates were significantly higher than those of transudates (P = 0.0300). Exudative pleural effusions show a significant enhancement following administration of Gd-DTPA. We presume that this may be caused by increased pleural permeability and more rapid passage of a large amount of Gd-DTPA from the blood into the pleural fluid in case of exudative effusions. In our limited group of patients, signal enhancement proved the presence of an exudative effusion. Absence of signal enhancement suggests a transudate, but does not exclude an exudate. (orig.). With 5 figs., 2 tabs

  8. Value of Gd-EOB-DTPA-enhanced MRI in diagnosis of hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    SUN Yu

    2018-01-01

    Full Text Available Objective To investigate the value of Gd-EOB-DTPA-enhanced MRI in the diagnosis of hepatocellular carcinoma (HCC. Methods A total of 40 patients with liver cirrhosis or suspected HCC who visited General Hospital of Shenyang Military Area Command from October 2016 to April 2017 were enrolled, and the data on three dynamic phases of Gd-EOB-DTPA-enhanced MRI (arterial phase, portal venous phase, and delayed phase, hepatobiliary phase (delayed for 20 minutes, and diffusion-weighted imaging (DWI (b=50,400, and 1000 s/mm2 were collected. Two radiologists made a diagnosis and gave diagnostic confidence scores based on the presence or absence of hepatobiliary phase images. Postoperative pathology or clinical diagnosis was used as the criteria for assessing the diagnostic accuracy of HCC. The t-test was used for comparison of continuous data, and the chi-square test was used for comparison of categorical data. Results A total of 42 HCC lesions and 37 cirrhotic nodules were detected. There were significant differences between HCC lesions and cirrhotic nodules in signal intensity on hepatobiliary phase and DWI (χ2=64.503 and 67.855, both P<0.001,as well as the apparent diffusion coefficient when the b-values of DWI were 400 s/mm2 and 1000 s/mm2 (t=62.75 and 75.36, both P<0.001. There was a significant difference in diagnostic confidence score given by the radiologists between the images of three dynamic phases of Gd-EOB-DTPA-enhanced MRI and those of four dynamic phases (including hepatobiliary phase (3.260±0.521 vs 4.620±0.661, t=10.67, P<0.001. With postoperative pathology and clinical diagnosis as criteria, the images of three dynamic phases of Gd-EOB-DTPA-enhanced MRI had a significantly higher diagnostic accuracy for HCC than those of four dynamic phases (including hepatobiliary phase [76.19% (32/42 vs 95.24% (40/42, χ2=6.222, P=0.013]. Conclusion Gd-EOB-DTPA-enhanced MRI may improve diagnostic accuracy and confidence for HCC and has

  9. Value of Gd-EOB-DTPA-enhanced MRI in assessing liver function

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    WANG Lili

    2015-05-01

    Full Text Available ObjectiveTo explore the value of magnetic resonance imaging (MRI specifically enhanced with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA in assessing the liver function in general population. MethodsUpper abdominal MRI images and Gd-EOB-DTPA-enhanced images, as well as some clinical information, were collected from 41 cases meeting the inclusion and exclusion criteria. Taking the spleen as the control organ, liver-spleen signal intensity contrast (SIliver/spleen and relative liver enhancement (RLE were calculated at 10 min and 20 min after injecting Gd-EOB-DTPA. Differences were evaluated using the independent-samples t-test or Mann-Whitney U test. Corrections were analyzed via Spearman’s rank correlation. ResultsBoth SIliver/spleen at 10 min and 20 min after injection of contrast agent were correlated with Child classification (P<0.05. SIliver/spleen at 20 min had a greater correlation coefficient (r=-0.526 than that at 10 min. The SIliver/spleen with plain scan had no significant correlation with Child classification (P>0.05. RLE at 20 min, but not at 10 min, was correlated with Child classification (r=-0.362, P=0049. Between the cirrhotic and non-cirrhotic groups, SIliver/spleen showed no significant difference (P>0.05. However, SIliver/spleen at 10 min and 20 min, as well as RLE20 min, showed significant differences between the cirrhotic and non-cirrhotic groups (P<0.05. SIliver/spleen at 20 min also exhibited a significant difference between the elevated and normal ALT and TBil groups (both P<0.05. ConclusionGd-EOB-DTPA-enhanced MRI can monitor liver function changes, and SIliver/spleen at 20 min may have an important value in assessing the liver function in general population.

  10. Utility of Gd-EOB-DTPA-Enhanced MRI in Diagnosing Small Hepatocellular Carcinoma

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    Soo Ryang Kim

    2009-07-01

    Full Text Available We describe an 8-mm hepatocellular carcinoma (HCC with hepatitis C virus-related cirrhosis in a 74-year-old woman. Ultrasound (US revealed an 8-mm hyperechoic nodule in segment 6 of the liver. Contrast-enhanced computed tomography (CT and US revealed no hypervascularity in the early phase and no washout in the late phase and the Kupffer phase, respectively. CT during arteriography revealed no hypervascularity and CT during arterial portography disclosed no perfusion defect. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI revealed no hypervascularity in the early phase, but disclosed a defect in the hepatobiliary phase. Histologically, the nodule was diagnosed as well-differentiated HCC characterized by more than two-fold the cellularity of the non-tumorous area, with a high nuclear:cytoplasmic ratio, increased cytoplasmic eosinophilia, fatty change, and slight cell atypia with an irregular thin trabecular pattern. Our case demonstrates the utility of Gd-EOB-DTPA-enhanced MRI in the diagnosis of small HCC.

  11. MRI enhancement of the facial nerve with Gd-DTPA, 1

    International Nuclear Information System (INIS)

    Yanagida, Masahiro

    1993-01-01

    Although there have recently been numerous reports of enhanced MRI in patients with facial palsy, the mechanism of enhancement remains largely unknown. In the present study, animal models with experimentally induced facial paralysis were prepared, and the vascular permeabilities of normal and damaged facial nerves were assessed using Evans blue albumin (EBA) as a tracer. The Gd-DTPA contents in normal and compressively damaged facial nerves were also investigated. In the normal intratemporal facial nerve, EBA remained in the vessels, and did not leak into the endoneurium. In contrast, vascular permeability was very high in the epineurium and the geniculate ganglion which showed leakage of large amounts of EBA from vessels. At the site of compression in the damaged nerve, EBA leakage was also seen in the endoneurism, indicating accentuated vascular permeability. This accentuation of vascular permeability shifted toward the distal side. However, no EBA leakage was seen on the side proximal to the site of compression. Significantly higher Gd-DTPA contents were obtained in the facial nerve on the paralytic side than in that on the normal side (p<0.001). As for differences between the distal and proximal sides, the distal side had a significantly higher Gd-DTPA content (p<0.01). Assessment of vascular permeability with EBA revealed accentuated vascular permeability on the side distal to the site of compression. These results showed the presence of a blood nerve barrier (BNB) in the facial nerve. Furthermore, the present findings suggest that the enhancement of the facial nerve on the affected side is caused by BNB destruction due to nerve damage and subsequent Gd-DTPA leakage from the vessels. Furthermore, it is suggested that the facial nerve enhancement appears to occur mainly on the distal side of the damaged portion of the nerve. (author)

  12. MRI enhancement of the facial nerve with Gd-DTPA, 2

    International Nuclear Information System (INIS)

    Yanagida, Masahiro

    1993-01-01

    We performed enhanced MRI using Gd-DTPA in 84 patients with facial palsy. After assessing enhancement of the normal facial nerve, we examined enhancement in patients with Bell's palsy and Ramsay Hunt syndrome. In 95% of patients with Bell's palsy, enhancement was obtained in the distal IAC and labyrinthine portions. In 72%, enhancement was significant from the distal IAC portion through the vertical portion. In some of the patients who underwent enhanced MRI twice, increased signal intensity was observed in distal portions such as the vertical portion. In many cases of Ramsay Hunt syndrome, enhancement was seen extensively in the IAC portion through the vertical portion. In the subjects with internal auditory symptoms such as vertigo and tinnitus, enhancement of the IAC portion was seen not only in the facial nerve but also in the vestibular and the cochlear nerves. These results suggest that the vascular permeability of lesions in Bell's palsy may be increased from the distal IAC portion to the vertical portion. Judging from the present findings with Ramsay Hunt syndrome, symptoms related to the enhanced portions suggest that accompanying internal auditory symptoms occur due to inflammation of the IAC portions of cochlear and vestibular nerves. (author)

  13. Hemophilic arthropathy of the knee joint: static and dynamic Gd-DTPA - enhanced MRI

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    Naegele, M. [Dept. of Radiology, Univ. Bonn (Germany); Bruening, R. [Dept. of Radiology, Univ. Muenchen (Germany); Kunze, V. [Dept. of Radiology, Univ. Bonn (Germany); Eickhoff, H. [Dept. of Orthopedic Surgery, Troisdorf (Germany); Koch, W. [Dept. of Orthopedic Surgery, Troisdorf (Germany); Reiser, M. [Dept. of Radiology, Univ. Muenchen (Germany)

    1995-12-31

    A total of 17 patients with hemophilic arthropathy of the knee joint were studied with static and dynamic MRI before and after an IV bolus injection of Gadolinium-DTPA (Gd-DTPA; 0.1 mmol/kg body weight). The T1-weighted spin-echo (SE) and gradient-echo (fast-field echo [FFE]) sequences were applied. The FFE sequences of eight consecutive scans carried out over a time interval of 160 s were used in order to determine the time to signal intensity (SI) curves of the synovial proliferations surrounding soft tissue, bone marrow, and joint effusion. After the administration of a contrast agent, synovial proliferations exhibited an increase on FFE and SE images of 47.7% (SD {+-} 14.3%) and 37.4% (SD {+-} 11.2%), respectively, whereas muscle and fatty tissue, tendons, bone marrow, and joint effusion revealed only a minor increase in SI. The gradient of SI (ratio SI/time) of pannus was 39.6%/min (SD {+-} 7.7%/min) and differed significantly (P < 0.001) from that of bone marrow, fatty tissue, muscle tissue, tendons, and joint effusion (P < 0.05). In contrast to synovial proliferations in rheumatoid arthritis, no differentiation between various pannus vascularities based on the degree of enhancement was possible. The Gd-DTPA-enhanced MRI studies delineate and quantify the synovial proliferations in hemophilic arthropathy. Dynamic studies in hemophilic arthropathy do not provide qualitative assessment of the inflammatory process. (orig.)

  14. Hemophilic arthropathy of the knee joint: static and dynamic Gd-DTPA -enhanced MRI

    International Nuclear Information System (INIS)

    Naegele, M.; Bruening, R.; Kunze, V.; Eickhoff, H.; Koch, W.; Reiser, M.

    1995-01-01

    A total of 17 patients with hemophilic arthropathy of the knee joint were studied with static and dynamic MRI before and after an IV bolus injection of Gadolinium-DTPA (Gd-DTPA; 0.1 mmol/kg body weight). The T1-weighted spin-echo (SE) and gradient-echo (fast-field echo [FFE]) sequences were applied. The FFE sequences of eight consecutive scans carried out over a time interval of 160 s were used in order to determine the time to signal intensity (SI) curves of the synovial proliferations surrounding soft tissue, bone marrow, and joint effusion. After the administration of a contrast agent, synovial proliferations exhibited an increase on FFE and SE images of 47.7% (SD ± 14.3%) and 37.4% (SD ± 11.2%), respectively, whereas muscle and fatty tissue, tendons, bone marrow, and joint effusion revealed only a minor increase in SI. The gradient of SI (ratio SI/time) of pannus was 39.6%/min (SD ± 7.7%/min) and differed significantly (P < 0.001) from that of bone marrow, fatty tissue, muscle tissue, tendons, and joint effusion (P < 0.05). In contrast to synovial proliferations in rheumatoid arthritis, no differentiation between various pannus vascularities based on the degree of enhancement was possible. The Gd-DTPA-enhanced MRI studies delineate and quantify the synovial proliferations in hemophilic arthropathy. Dynamic studies in hemophilic arthropathy do not provide qualitative assessment of the inflammatory process. (orig.)

  15. Quantitative evaluation of enhancement patterns in focal solid liver lesions with Gd-EOB-DTPA-enhanced MRI.

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    Michael Haimerl

    Full Text Available PURPOSE: The objective was to investigate the dynamic enhancement patterns in focal solid liver lesions after the administration of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA by means of dynamic magnetic resonance imaging (MRI including hepatobiliary phase (HP images 20 min after Gd-EOB-DTPA administration. MATERIALS AND METHODS: Non-enhanced T1/T2-weighted as well as dynamic magnetic resonance (MR images during the arterial phase (AP, the portal venous phase (PVP, the late phase (LP, and the HP (20 min were obtained from 83 patients (54 male, 29 female, mean age 62.01 years with focal solid liver lesions. MRI was conducted by means of a 1.5-T system for 63 patients with malignant liver lesions (HCCs: n = 34, metastases: n = 29 and for 20 patients with benign liver lesions (FNH lesions: n = 14, hemangiomas: n = 3, adenomas: n = 3. For quantitative analysis, signal-to-noise ratios (SNR, contrast enhancement ratios (CER, lesion-to-liver contrast ratios (LLC, and signal intensity (SI ratios were measured. RESULTS: The SNR of liver parenchyma significantly increased in each dynamic phase after Gd-EOB-DTPA administration compared to the SNR of non-enhanced images (p<0.001. The CER of HCCs and metastases significantly decreased between LP and HP images (p = 0.0011, p<0.0001. However, FNH lesions did not show any significant difference, whereas an increased CER was found in hemangiomas. The mean LLCs of FNH lesions were significantly higher than those of HCCs and metastases. The LLC values of hemangiomas remained negative during the entire time course, whereas the LLC of adenomas indicated hyperintensity from the AP to the LP. Furthermore, adenomas showed hypointensity in HP images. CONCLUSION: Gd-EOB-DTPA-enhanced MRI may help diagnose focal solid liver lesions by evaluating their enhancement patterns.

  16. Value of contrast enhancement with Gd-DTPA in MRI of brain tumors. A comparison with X-ray CT

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    Tsuji, Takehisa; Kishikawa, Takashi; Ikezaki, Kiyonobu; Fujii, Kiyotaka; Matsumoto, Shunichi; Koga, Toshihiko.

    1987-12-01

    Value of administration of Gadolinium-DTPA dimeglumine (Gd-DTPA), a magnetic resonance contrast agent, in MRI was evaluated in 17 patients of primary brain tumors and 3 metastatic tumors with known pathology, comparing with CT findings. MRI was performed with T/sub 1/-weighted spin echo pulse sequence (SE 50030) prior to and following the intravenous injection of 0.10 mmolkg Gd-DTPA. All, but one pituitary microadenoma, the tumors including meningiomas, pituitary adenomas, gliomas, intraventricular craniopharyngioma and acoustic neurinoma and metastatic lung adenocarcinomas, were enhanced by Gd-DTPA on T/sub 1/-weighted images. Good definition of the exact boundaries and extent of the mass to the surrounding structures were obtained in all these cases. Especially, the invasion of meningioma to the dura mater or to the venous sinus, and that of cerebellopontine angle tumor to the internal auditory meatus or to the jugular foramen, were better delineated on MRI as compared with CT. The anatomical relationship to the surrounding structures in the sellar or parasellar tumors were also clearly demonstrated on MRI. Thus, MRI with Gd-DTPA administration was useful for the preoperative assessment and Gd-DTPA appears to be a safe contrast agent for MRI since there were no significant untoward reactions in our series.

  17. Efficacy of liver parenchymal enhancement and liver volume to standard liver volume ratio on Gd-EOB-DTPA-enhanced MRI for estimation of liver function

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    Yoneyama, Tomohide; Fukukura, Yoshihiko; Kamimura, Kiyohisa; Takumi, Koji; Umanodan, Aya; Nakajo, Masayuki [Kagoshima University Graduate School of Medical and Dental Sciences, Department of Radiology, Kagoshima City (Japan); Ueno, Shinichi [Kagoshima University Graduate School of Medical and Dental Sciences, Department of Surgical Oncology and Digestive Surgery, Kagoshima City (Japan)

    2014-04-15

    We aimed to develop and assess the efficacy of a liver function index that combines liver enhancement and liver volume to standard liver volume (LV/SLV) ratio on gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI. In all, 111 patients underwent a Gd-EOB-DTPA-enhanced MRI, including T1 mapping, before and 20 min after Gd-EOB-DTPA administration. We calculated the following Gd-EOB-DTPA-enhanced MRI-based liver function indices: relative enhancement of the liver, corrected enhancement of the liver-to-spleen ratio, LSC{sub N}20, increase rate of the liver-to-muscle ratio, reduction rate of T1 relaxation time of the liver, ΔR1 of the liver and K{sub Hep}; the indices were multiplied by the LV/SLV ratio. We calculated the correlations between an indocyanine green (ICG) clearance and the Gd-EOB-DTPA-enhanced MRI-based liver function indices multiplied by the LV/SLV ratio, by using Pearson correlation analysis. There were significant correlations between all Gd-EOB-DTPA-enhanced MRI-based liver function indices and ICG clearance (r = -0.354 to -0.574, P < 0.001). All Gd-EOB-DTPA-enhanced MRI-based liver function indices multiplied by the LV/SLV ratio (r = -0.394 to -0.700, P < 0.001) were more strongly correlated with the ICG clearance than those without multiplication by the LV/SLV ratio. Gd-EOB-DTPA-enhanced MRI-based liver function indices that combine liver enhancement and the LV/SLV ratio may more reliably estimate liver function. (orig.)

  18. Assessment of fixed charge density in regenerated cartilage by Gd-DTPA-enhanced MRI

    International Nuclear Information System (INIS)

    Miyata, Shogo; Homma, Kazuhiro; Numano, Tomokazu; Furukawa, Katsuko; Tateishi, Tetsuya; Ushida, Takashi

    2006-01-01

    Applying regenerated cartilage in a clinical setting requires noninvasive evaluation to detect the maturity of cartilage tissue. Magnetic resonance (MR) imaging of articular cartilage is well accepted and has been applied clinically in recent years. We attempt to establish a noninvasive method to evaluate the maturity of regenerated cartilage tissue using gadolinium-enhanced MR imaging. To reconstruct cartilaginous tissue, we embedded articular chondrocytes harvested from bovine humeral head in agarose gel and cultured the cells in vitro up to 4 weeks. The fixed charge density (FCD) of the cartilage was determined using MRI gadolinium exclusion method. The sulfated glycosaminoglycan (sGAG) content was determined by dimethylmethylene blue dye-binding assay. The sGAG content and FCD of the regenerated cartilage increased with duration of culture. In the T 1 Gd maps, the [Gd-DTPA 2- ] in the specimen decreased, and the boundary between the sample disk and the bath solution of phosphate buffered saline (PBS) became clearer as time in culture increased. In the linear regression analysis, FCD and sGAG content correlated significantly. Gadolinium-enhanced MR imaging measurements can be useful predictors of the degree of cartilaginous tissue formation. (author)

  19. Multivariable analysis of clinical influence factors on liver enhancement of Gd-EOB-DTPA-enhanced 3T MRI

    International Nuclear Information System (INIS)

    Verloh, N.; Haimerl, M.; Stroszczynski, C.; Fellner, C.; Wiggermann, P.; Zeman, F.; Teufel, A.; Lang, S.

    2015-01-01

    The purpose of this study was to identify clinical factors influencing Gd-EOB-DTPA liver uptake in patients with healthy liver parenchyma. A total of 124 patients underwent contrast-enhanced MRI with a hepatocyte-specific contrast agent at 3T. T1-weighted volume interpolated breath-hold examination (VIBE) sequences with fat suppression were acquired before and 20 minutes after contrast injection. The relative enhancement (RE) between plain and contrast-enhanced signal intensity was calculated. Simple and multiple linear regression analyses were performed to evaluate clinical factors influencing the relative enhancement. Patients were subdivided into three groups according to their relative liver enhancement (HRE, RE ≥ 100 %; MRE, 100 % > RE > 50 %; NRE, RE ≤ 50 %) and were analyzed according to the relevant risk factors. Simple regression analyses revealed patient age, transaminases (AST, ALT, GGT), liver, spleen and delta-liver volume (the difference between the volumetrically measured liver volume and the estimated liver volume based on body weight) as significant factors influencing relative enhancement. In the multiple analysis the transaminase AST, spleen and delta liver volume remained significant factors influencing relative enhancement. Delta liver volume showed a significant difference between all analyzed groups. Liver enhancement in the hepatobiliary phase depends on a variety of factors. Body weight-adapted administration of Gd-EOB-DTPA may lead to inadequate liver enhancement after 20 minutes especially when the actual liver volume differs from the expected volume.

  20. MRI contrast enhancement of the lung using as Gd-DTPA aerosol

    International Nuclear Information System (INIS)

    Bockisch, A.; Harvey, R.C.; Davis, M.A.; Kabalka, G.W.

    1993-01-01

    The efficacy of a Gd-DTPA aerosol to enhance ventilated lung parenchyma was evaluated in an MR study in anesthetized female beagle dogs. Ventilation of a 1.0-M Gd-DTPA solution was performed using a commercially available atomizer. MR imaging was performed at a 1.9 T whole body imager with an acquisition mode that was gated to respiration. To quantify the amount of ventilated Gd-DTPA experiments were repeated with 99m Tc-DTPA under identical conditions. Using ventral and dorsal digital scintigraphy, the amount of Gd-DTPA in both lungs were determined. MR imaging showed on increase of signal intensity of 70% following Gd-DTPA ventilation. Because of the inherently low signal intensity of lung parenchyma this degree of contrast enhancement is too small to be clinically useful. (orig.) [de

  1. 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

  2. Evaluation of the MRI with Gd-DTPA enhancement in the diagnosis of brain and spinal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, Keiji; Sadamoto, Kazuhiko; Miki, Hitoshi; Sakaki, Saburo; Matsuoka, Kenzo.

    1988-02-01

    Magnetic resonance (MR) imaging was performed using saturation recovery (SR), inversion recovery (IR) and spin echo (SE) pulse sequences before and after the injection of 0.1 mmol of gadolinium diethylenetriamine pentaacetic acid dimeglumine (Gd-DTPA) per kilogram of body weight. Forty-two patients with gliomas (8), meningiomas (12), neurinomas (5), adenoma (1), craniopharyngioma (1), chordoma (1), malignant lymphomas (2), metastatic brain tumors (2), spinal tumors (4), and other tumors (6) were studied. Contrast enhancement was shown in 35 of the 38 patients with brain tumors and in all those with spinal tumors on T/sub 1/-weighted images. The T/sub 1/ relaxation time was decreased in all of these 39 tumors, while the T/sub 2/ relaxation time showed no definite tendency. No marked side effects were observed following the administration of Gd-DTPA. By using Gd-DTPA enhancement, it was possible to differentiate the tumor from the peritumoral edema on MRI, although it was difficult to do so on precontrast MRI. Among the various pulse sequences, the SR sequence provides the best diagnostic value with Gd-DTPA enhancement in the shortest examination time for screening brain and spinal tumors.

  3. A study utility of gadolinium enhanced magnetic resonance imaging (Gd-MRI) in the preoperative diagnosis of lymph node metastasis of esophageal carcinoma

    International Nuclear Information System (INIS)

    Makino, Harufumi

    1997-01-01

    We evaluated the utility of gadolinium enhanced magnetic resonance imaging (Gd-MRI) in the diagnosis of lymph node metastasis of esophageal carcinoma. Gd-MRI was performed in 42 patients with esophageal carcinoma. The intensities of 50 lymph nodes in MR imaging were measured. No differences were observed in intensity between metastatic and non-metastatic nodes. However, intensity values did overlap. Thus, the author devised a new method allowing comparison of metastatic and non-metastatic nodes on Gd-MRI utilizing an enhancement ratio (ER). ER higher than 45% reflected metastatic nodes. (author)

  4. Hydrothermally synthesized PEGylated calcium phosphate nanoparticles incorporating Gd-DTPA for contrast enhanced MRI diagnosis of solid tumors.

    Science.gov (United States)

    Mi, Peng; Kokuryo, Daisuke; Cabral, Horacio; Kumagai, Michiaki; Nomoto, Takahiro; Aoki, Ichio; Terada, Yasuko; Kishimura, Akihiro; Nishiyama, Nobuhiro; Kataoka, Kazunori

    2014-01-28

    Organic-inorganic hybrid nanoparticles with calcium phosphate (CaP) core and PEGylated shell were developed to incorporate magnetic resonance imaging (MRI) contrast agent diethylenetriaminepentaacetic acid gadolinium (III) (Gd-DTPA) for noninvasive diagnosis of solid tumors. A two-step preparation method was applied to elaborate hybrid nanoparticles with a z-average hydrodynamic diameter about 80nm, neutral surface ξ-potential and high colloidal stability in physiological environments by self-assembly of poly(ethylene glycol)-b-poly(aspartic acid) block copolymer, Gd-DTPA, and CaP in aqueous solution, followed with hydrothermal treatment. Incorporation into the hybrid nanoparticles allowed Gd-DTPA to show significant enhanced retention ratio in blood circulation, leading to high accumulation in tumor positions due to enhanced permeability and retention (EPR) effect. Moreover, Gd-DTPA revealed above 6 times increase of relaxivity in the nanoparticle system compared to free form, and eventually, selective and elevated contrast enhancements in the tumor positions were observed. These results indicate the high potential of Gd-DTPA-loaded PEGylated CaP nanoparticles as a novel contrast agent for noninvasive cancer diagnosis. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Gd2O3 nanoparticles in hematopoietic cells for MRI contrast enhancement

    Directory of Open Access Journals (Sweden)

    Hedlund A

    2011-12-01

    Full Text Available Anna Hedlund1,2, Maria Ahrén3, Håkan Gustafsson1,2, Natalia Abrikossova3, Marcel Warntjes2,4, Jan-Ingvar Jönsson5, Kajsa Uvdal3, Maria Engström1,21Division of Radiology, Department of Medical and Health Sciences, 2Center for Medical Image Science and Visualization, 3Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry, and Biology, 4Division of Clinical Physiology, Department of Medicine and Health Sciences, 5Department of Clinical and Experimental Medicine, Experimental Hematology Unit, Linköping University, Linköping, SwedenAbstract: As the utility of magnetic resonance imaging (MRI broadens, the importance of having specific and efficient contrast agents increases and in recent time there has been a huge development in the fields of molecular imaging and intracellular markers. Previous studies have shown that gadolinium oxide (Gd2O3 nanoparticles generate higher relaxivity than currently available Gd chelates: In addition, the Gd2O3 nanoparticles have promising properties for MRI cell tracking. The aim of the present work was to study cell labeling with Gd2O3 nanoparticles in hematopoietic cells and to improve techniques for monitoring hematopoietic stem cell migration by MRI. Particle uptake was studied in two cell lines: the hematopoietic progenitor cell line Ba/F3 and the monocytic cell line THP-1. Cells were incubated with Gd2O3 nanoparticles and it was investigated whether the transfection agent protamine sulfate increased the particle uptake. Treated cells were examined by electron microscopy and MRI, and analyzed for particle content by inductively coupled plasma sector field mass spectrometry. Results showed that particles were intracellular, however, sparsely in Ba/F3. The relaxation times were shortened with increasing particle concentration. Relaxivities, r1 and r2 at 1.5 T and 21°C, for Gd2O3 nanoparticles in different cell samples were 3.6–5.3 s-1 mM-1 and 9.6–17.2 s-1 mM-1

  6. Gd-functionalised Au nanoparticles as targeted contrast agents in MRI: relaxivity enhancement by polyelectrolyte coating.

    Science.gov (United States)

    Warsi, Muhammad Farooq; Adams, Ralph W; Duckett, Simon B; Chechik, Victor

    2010-01-21

    Monolayer-protected, Gd(3+)-functionalised gold nanoparticles with enhanced spin-lattice relaxivity (r(1)) were prepared; adsorption of polyelectrolytes on these materials further increased r(1) and ligand exchange with a biotin-derivatised disulfide led to a prototype avidin-targeted contrast agent.

  7. Impact of liver cirrhosis on liver enhancement at Gd-EOB-DTPA enhanced MRI at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Verloh, N., E-mail: niklas.verloh@stud.uni-regensburg.de [Department of Radiology, University Hospital Regensburg, Regensburg (Germany); Haimerl, M.; Rennert, J.; Müller-Wille, R.; Nießen, C. [Department of Radiology, University Hospital Regensburg, Regensburg (Germany); Kirchner, G. [Department of Gastroenterology, University Hospital Regensburg, Regensburg (Germany); Scherer, M.N. [Department of Surgery, University Hospital Regensburg, Regensburg (Germany); Schreyer, A.G.; Stroszczynski, C.; Fellner, C.; Wiggermann, P. [Department of Radiology, University Hospital Regensburg, Regensburg (Germany)

    2013-10-01

    Purpose: The purpose of this study was to assess differences in enhancement effects of liver parenchyma between normal and cirrhotic livers on dynamic, Gd-EOB-DTPA enhanced MRI at 3 T. Materials and methods: 93 patients with normal (n = 54) and cirrhotic liver (n = 39; Child–Pugh class A, n = 18; B, n = 16; C, n = 5) underwent contrast-enhanced MRI with liver specific contrast media at 3 T. T1-weighted volume interpolated breath hold examination (VIBE) sequences with fat suppression were acquired before contrast injection, in the arterial phase (AP), in the late arterial phase (LAP), in the portal venous phase (PVP), and in the hepatobiliary phase (HBP) after 20 min. The relative enhancement (RE) of the signal intensity of the liver parenchyma was calculated for all phases. Results: Mean RE was significantly different among all evaluated groups in the hepatobiliary phase and with increasing severity of liver cirrhosis, a decreasing, but still significant reduction of RE could be shown. Phase depending changes of RE for each group were observed. In case of non-cirrhotic liver or Child–Pugh Score A cirrhosis mean RE showed a significant increase between AP, LAP, PVP and HBP. For Child–Pugh B + C cirrhosis RE increased until PVP, however, there was no change in case of B cirrhosis (p = 0.501) and significantly reduced in case of C cirrhosis (p = 0.043) during HBP. Conclusion: RE of liver parenchyma is negatively affected by increased severity of liver cirrhosis, therefore diagnostic value of HBP could be limited in case of Child Pugh B + C cirrhosis.

  8. Impact of liver cirrhosis on liver enhancement at Gd-EOB-DTPA enhanced MRI at 3 Tesla

    International Nuclear Information System (INIS)

    Verloh, N.; Haimerl, M.; Rennert, J.; Müller-Wille, R.; Nießen, C.; Kirchner, G.; Scherer, M.N.; Schreyer, A.G.; Stroszczynski, C.; Fellner, C.; Wiggermann, P.

    2013-01-01

    Purpose: The purpose of this study was to assess differences in enhancement effects of liver parenchyma between normal and cirrhotic livers on dynamic, Gd-EOB-DTPA enhanced MRI at 3 T. Materials and methods: 93 patients with normal (n = 54) and cirrhotic liver (n = 39; Child–Pugh class A, n = 18; B, n = 16; C, n = 5) underwent contrast-enhanced MRI with liver specific contrast media at 3 T. T1-weighted volume interpolated breath hold examination (VIBE) sequences with fat suppression were acquired before contrast injection, in the arterial phase (AP), in the late arterial phase (LAP), in the portal venous phase (PVP), and in the hepatobiliary phase (HBP) after 20 min. The relative enhancement (RE) of the signal intensity of the liver parenchyma was calculated for all phases. Results: Mean RE was significantly different among all evaluated groups in the hepatobiliary phase and with increasing severity of liver cirrhosis, a decreasing, but still significant reduction of RE could be shown. Phase depending changes of RE for each group were observed. In case of non-cirrhotic liver or Child–Pugh Score A cirrhosis mean RE showed a significant increase between AP, LAP, PVP and HBP. For Child–Pugh B + C cirrhosis RE increased until PVP, however, there was no change in case of B cirrhosis (p = 0.501) and significantly reduced in case of C cirrhosis (p = 0.043) during HBP. Conclusion: RE of liver parenchyma is negatively affected by increased severity of liver cirrhosis, therefore diagnostic value of HBP could be limited in case of Child Pugh B + C cirrhosis

  9. Safety of meglumine gadoterate (Gd-DOTA)-enhanced MRI compared to unenhanced MRI in patients with chronic kidney disease (RESCUE study)

    Energy Technology Data Exchange (ETDEWEB)

    Deray, Gilbert [Pitie Salpetriere Hospital, Department of Nephrology, Paris cedex 13 (France); Rouviere, Olivier [Hopital E. Herriot, Universite de Lyon, Hospices Civils de Lyon, Department of Urinary and Vascular Imaging, Lyon (France); Universite Lyon 1, faculte de medecine Lyon Est, Lyon (France); Bacigalupo, Lorenzo [E.O. Ospedali Galliera, Radiology Department, Genova (Italy); Maes, Bart [Heilig Hartziekenhuis Roeselare, Department of Nephrology, Roeselare (Belgium); Hannedouche, Thierry [University Hospitals, Department of Nephrology, Strasbourg (France); Vrtovsnik, Francois [Bichat Hospital, Department of Nephrology, Paris (France); Rigothier, Claire [Pellegrin Hospital, Department of Nephrology Transplantation Dialysis, Bordeaux (France); Billiouw, Jean-Marie [Onze Lieve Vrouw Ziekenhuis, Department of Nephrology, Aalst (Belgium); Campioni, Paolo [Azienda Ospedaliero-Universitaria Sant' Anna, Ferrara (Italy); Ferreiros, Joaquin [Hospital Clinico de San Carlos, Servicio de Radiodiagnostico, Madrid (Spain); Devos, Daniel [Gent University Hospital, Department of Radiology, Gent (Belgium); Alison, Daniel [Trousseau Hospital, Department of Radiology, Tours (France); Glowacki, Francois [University Hospitals, Department of Nephrology, Lille (France); Boffa, Jean-Jacques [Tenon Hospital, Department of Nephrology and Dialysis, Paris (France); Marti-Bonmati, Luis [University of Valencia, Department of Radiology, Valencia (Spain)

    2013-05-15

    To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients. Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72 {+-} 24 h after the MRI procedure, by at least 25 % or 44.2 {mu}mol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at -15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72 {+-} 24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up. Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [{Delta} = -1.4 %, 95%CI = (-7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P = 0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted. Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD. (orig.)

  10. Safety of meglumine gadoterate (Gd-DOTA)-enhanced MRI compared to unenhanced MRI in patients with chronic kidney disease (RESCUE study)

    International Nuclear Information System (INIS)

    Deray, Gilbert; Rouviere, Olivier; Bacigalupo, Lorenzo; Maes, Bart; Hannedouche, Thierry; Vrtovsnik, Francois; Rigothier, Claire; Billiouw, Jean-Marie; Campioni, Paolo; Ferreiros, Joaquin; Devos, Daniel; Alison, Daniel; Glowacki, Francois; Boffa, Jean-Jacques; Marti-Bonmati, Luis

    2013-01-01

    To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients. Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72 ± 24 h after the MRI procedure, by at least 25 % or 44.2 μmol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at -15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72 ± 24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up. Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [Δ = -1.4 %, 95%CI = (-7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P = 0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted. Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD. (orig.)

  11. Non-hypervascular hypointense nodules on Gd-EOB-DTPA-enhanced MRI as a predictor of outcomes for early-stage HCC.

    Science.gov (United States)

    Toyoda, Hidenori; Kumada, Takashi; Tada, Toshifumi; Sone, Yasuhiro; Maeda, Atsuyuki; Kaneoka, Yuji

    2015-01-01

    In patients with hepatocellular carcinoma (HCC), gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) often identifies non-hypervascular hypointense hepatic nodules during the hepatobiliary phase, but their prognostic significance is unclear. We conducted a prospective observational study to investigate the impact of non-hypervascular hypointense hepatic nodules detected by Gd-EOB-DTPA-enhanced MRI on the outcome of patients with early-stage HCC. Post-treatment recurrence and survival rates were analyzed in 138 patients with non-recurrent, early-stage HCC [Barcelona Clinic Liver Cancer (BCLC) stage 0 or A] and Child-Pugh A liver function according to the presence of non-hypervascular hypointense nodules on pretreatment Gd-EOB-DTPA-enhanced MRI. Non-hypervascular hypointense hepatic nodules were detected in 51 (37.0%) patients with early-stage HCC on pretreatment Gd-EOB-DTPA-enhanced MRI. Recurrence rates were significantly higher in patients with non-hypervascular hypointense nodules (p DTPA-enhanced MRI was independently associated with an increased recurrence rate, independent of tumor progression or treatment (p = 0.0005). The survival rate was significantly lower in patients with non-hypervascular hypointense nodules on Gd-EOB-DTPA-enhanced MRI (p = 0.0108). In patients with early-stage typical HCC (BCLC 0 or A), the presence of concurrent non-hypervascular hypointense hepatic nodules in the hepatobiliary phase of pretreatment Gd-EOB-DTPA-enhanced MRI is an indicator of higher likelihood of recurrence after treatment and may be a marker for unfavorable outcome.

  12. Time-intensity curve in the abdominal aorta on dynamic contrast-enhanced MRI with high temporal and spatial resolution. Gd-EOB-DTPA versus Gd-DTPA in vivo

    International Nuclear Information System (INIS)

    Fujinaga, Yasunari; Tsukahara, Yoshinori; Sugiyama, Yukiko; Kadoya, Masumi; Ueda, Hitoshi; Kitou, Yoshihiro

    2013-01-01

    The purpose of this study was to evaluate the difference in the time-intensity curves (TICs) of the abdominal aorta on dynamic contrast-enhanced MRI (DCE-MRI) between gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) and gadolinium ethoxybenzydiethylenetriamine pentaacetic acid (Gd-EOB-DTPA). Ten healthy volunteers underwent DCE-MRI three times with the following protocol: group A, Gd-DTPA at an injection rate of 3 ml/s; group B, Gd-EOB-DTPA, 3 ml/s; group C, Gd-EOB-DTPA, 1.5 ml/s. Signal intensities (SIs) of the abdominal aorta were measured, and the contrast enhancement ratio (CER) was calculated. Time-to-CER curves were compared among the three groups. The differences in maximum CER (CER max ) and time-to-peak of CER were analyzed. The time-to-CER curve showed a double peak pattern in group A and single-peak pattern in groups B and C. The mean time between the first and the second peak was 6.2 s. The mean CER max of each group was 4.50, 4.52 and 4.27, respectively. In group A, B and C, the mean time-to-peak was 14.6, 10.6 and 12.6 s, respectively. There was a significant difference between group A and B (P<0.01). To set up the optimal protocol for abdominal DCE-MRI, it should be noted that TIC in the Gd-DTPA and Gd-EOB-DTPA group showed different patterns, and a slower injection rate showed a less abrupt SI change in the Gd-EOB-DTPA group than in the Gd-DTPA group. (author)

  13. Differentiation of hypertensive heart disease with hypertrophy and hepertrophic cardiomyopathy using consecutive time-course images of Gd-DTPA enhanced MRI

    International Nuclear Information System (INIS)

    Ochiai, Kouichi; Isibashi, Yutaka; Shimada, Toshio; Tsukihashi, Hironori; Sato, Hidetoshi; Kitamura, Jun; Morioka, Shigefumi; Kawamitsu, Hideaki; Sugimura, Kazuro

    1996-01-01

    We used consecutive time-course Gd-DTPA contrast magnetic resonance images to differentiate hypertrophic cardiomyopathy (HCM) from hypertensive heart disease with hypertrophy (HHD). Seventeen patients with HCM, 6 patients with HHD and 5 normal subjects (control) were studied. ECG-gated MRI with 1.5T system was performed before and after intravenous injection of Gd-DTPA (0.1mmol/Kg) using spin echo sequence. Gd-DTPA enhanced MRI was repeated every 10 to 55 minutes. We measured signal intensity (SI) of midleft ventricular myocardium and skeletal muscle, and then calculated the ratio between myocardial SI and skeletal muscle SI. Myocardium was enhanced by Gd-DTPA in all patients. However, there was difference in the decay of enhancement effect by Gd-DTPA between HCM and HHD. The decay in HCM was more slowly than in both HHD and control. There was no difference in the decay between HHD and control. The difference in the decay between HCM and HHD became significant 25 minutes after Gd-DTPA injection and lasted until 55 minutes. We conclude that the time-course of the decay of enhancement effect by Gd-DTPA is helpful to differentiate HCM from HHD and the difference of the decay might reflect structural changes of myocardium. (author)

  14. Early versus late GD-DTPA MRI enhancement in experimental glioblastomas.

    Science.gov (United States)

    Farace, Paolo; Tambalo, Stefano; Fiorini, Silvia; Merigo, Flavia; Daducci, Alessandro; Nicolato, Elena; Conti, Giamaica; Degrassi, Anna; Sbarbati, Andrea; Marzola, Pasquina

    2011-03-01

    To compare early versus late enhancement in two glioblastoma models characterized by different infiltrative/edematous patterns. Three weeks after inoculation into nude mice of U87MG and U251 cells, T1-weighted images were acquired early (10.5 min), intermediate (21 min) and late (30.5 min) after a bolus injection of Gd-DTPA at 300 μ mol/kg dosage. EARLY(TH) and LATE(TH) were the corresponding volumes with an enhancement higher than a threshold TH, defined by the mean (μ) and standard deviation (σ) on a contralateral healthy area. ADD(TH) was the enhancing volume found in LATE(TH) but not in EARLY(TH). T2 imaging of both tumors was performed, and T2 mapping of U251. In all tumors, LATE(TH) was significantly higher than EARLY(TH) for TH ranging from μ+σ to μ+5σ. The ADD(TH) /EARLY(TH) ratio was not significantly different when U251 and U87MG tumors were compared. In the U87MG tumors, some enhancement was observed outside the regularly demarcated T2-hyperintense area. In the U251 tumors, irregularly T2 demarcated, a large portion of ADD(μ+3σ) had normal T2 values. At histology, U251 showed a higher infiltrative pattern than U87MG. In these models, the increase over time in the enhancing volume did not depend on the different infiltrative/edematous patterns and was not closely related with edema. Copyright © 2011 Wiley-Liss, Inc.

  15. Gd-EOB-DTPA enhanced MRI of the liver: Correlation of relative hepatic enhancement, relative renal enhancement, and liver to kidneys enhancement ratio with serum hepatic enzyme levels and eGFR

    Energy Technology Data Exchange (ETDEWEB)

    Talakic, Emina; Steiner, Jürgen; Kalmar, Peter; Lutfi, Andre [Division of General Radiology, Department of Radiology, Medical University of Graz, Auenbruggerplatz 9, 8036 Graz (Austria); Quehenberger, Franz [Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Auenbruggerplatz 2, 8036 Graz (Austria); Reiter, Ursula; Fuchsjäger, Michael [Division of General Radiology, Department of Radiology, Medical University of Graz, Auenbruggerplatz 9, 8036 Graz (Austria); Schöllnast, Helmut, E-mail: helmut.schoellnast@medunigraz.at [Division of General Radiology, Department of Radiology, Medical University of Graz, Auenbruggerplatz 9, 8036 Graz (Austria)

    2014-04-15

    Objectives: To assess the correlation of relative hepatic enhancement (RHE), relative renal enhancement (RRE) and liver to kidneys enhancement ratio (LKR) with serum hepatic enzyme levels and eGFR in Gd-EOB-DTPA enhanced MRI of the liver and to assess threshold levels for predicting enhancement of the liver parenchyma. Methods: Data of 75 patients who underwent Gd-EOB-DTPA enhanced MRI of the liver were collected. Images were obtained before contrast injection, during the early arterial phase, late arterial phase, venous phase, delayed phase, and hepatobiliary phase which was 20 min after Gd-EOB-DTPA administration. Signal intensity of the liver and the kidneys in all phases was defined using region-of-interest measurements for relative enhancement calculation. Serum hepatic enzyme levels and eGFR were available in all patients. Spearman correlation test was used to test the correlation of RHE, RRE and LKR with serum hepatic enzyme levels and eGFR. Results: In the hepatobiliary phase all serum hepatic enzymes were significantly correlated with RHE; total bilirubin (TBIL) and cholin esterase (CHE) showed strongest correlations. TBIL and CHE were significantly correlated with RRE in the arterial phases. TBIL and CHE were significantly correlated with LKR in the arterial phase and hepatobiliary phase. eGFR showed no correlation. Conclusions: In Gd-EOB-DTPA enhanced MRI, TBIL and CHE levels may predict RHE, RRE and LKR.

  16. Gd-EOB-DTPA-Enhanced MRI for Detection of Liver Metastases from Colorectal Cancer: A Surgeon’s Perspective!

    Directory of Open Access Journals (Sweden)

    Kelly J. Lafaro

    2013-01-01

    Full Text Available Colorectal cancer affects over one million people worldwide annually, with the liver being the most common site of metastatic spread. Adequate resection of hepatic metastases is the only chance for a cure in a subset of patients, and five-year survival increases to 35% with complete resection. Traditionally, computed tomographic imaging (CT was utilized for staging and to evaluate metastases in the liver. Recently, the introduction of hepatobiliary contrast-enhanced magnetic resonance imaging (MRI agents including gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Eovist in the United States, Primovist in Europe, or Gd-EOB-DTPA has proved to be a sensitive method for detection of hepatic metastases. Accurate detection of liver metastases is critical for staging of colorectal cancer as well as preoperative planning.

  17. Gd-EOB-DTPA-enhanced MRI for monitoring future liver remnant function after portal vein embolization and extended hemihepatectomy: A prospective trial.

    Science.gov (United States)

    Geisel, Dominik; Raabe, Philip; Lüdemann, Lutz; Malinowski, Maciej; Stockmann, Martin; Seehofer, Daniel; Pratschke, Johann; Hamm, Bernd; Denecke, Timm

    2017-07-01

    To evaluate changes in liver function after right portal vein embolization (PVE) and extended right hemihepatectomy using gadolinium ethoxybenzyl-DTPA-enhanced (Gd-EOB-DTPA) MRI. In this prospective trial, 37 patients undergoing PVE were examined before and 14 and 28 days after PVE and 10 days after extended hemihepatectomy using Gd-EOB-DTPA-enhanced MRI. Lobar volume, kinetic growth rate (KGR), relative enhancement (RE) as well as hepatocellular uptake index (HUI) and fat signal fraction (FSF) were calculated for each lobe. RE of the left liver lobe (LLL) was steadily increasing after PVE and decreased to 0.48 ± 0.19 10 days after surgery, which is significantly lower than 14 days and 28 days post PVE (P DTPA-enhanced MRI may be used to monitor the functional increase in the FLR after PVE and to depict the intraoperative liver injury leading to a decrease in liver remnant function. • The most significant FLR volume increase happens within the first 14 days. • No MRI parameter was able to predict the success of FLR growth. • Our data suggest an early resection about 14 days after PVE. • Routine Gd-EOB-DTPA-enhanced MRI might be suitable to replace ICG-test.

  18. Imaging-based evaluation of liver function: comparison of {sup 99m}Tc-mebrofenin hepatobiliary scintigraphy and Gd-EOB-DTPA-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Geisel, Dominik; Gebauer, Bernhard [Charite Campus Virchow-Klinikum, Department of Diagnostic and Interventional Radiology, Berlin (Germany); Luedemann, Lutz [Essen University Hospital, Department of Medical Physics, Essen (Germany); Froeling, Vera; Denecke, Timm [Charite Campus Virchow-Klinikum, Department of Diagnostic and Interventional Radiology, Berlin (Germany); Charite Campus Virchow-Klinikum, Department of Nuclear Medicine, Berlin (Germany); Malinowski, Maciej; Stockmann, Martin; Baron, Annekathrin; Seehofer, Daniel [Charite Campus Virchow-Klinikum, Department of General, Visceral and Thoracic Surgery, Berlin (Germany); Prasad, Vikas [Charite Campus Virchow-Klinikum, Department of Nuclear Medicine, Berlin (Germany)

    2015-05-01

    To compare Gd-EOB-enhanced MRI and {sup 99m}Tc-mebrofenin hepatobiliary scintigraphy (HBS) as imaging-based liver function tests for separate evaluation of right (RLL) and left liver lobe (LLL) function. Fourteen patients underwent Gd-EOB-enhanced MRI and {sup 99m}Tc-mebrofenin HBS after portal vein embolization within 24 h. Relative enhancement (RE) and hepatic uptake index (HUI) were determined from MRI; and T{sub max}, T{sub 1/2} and mebrofenin uptake were determined from HBS, all values separately for RLL and LLL. Mebrofenin uptake correlated significantly with HUI and RE for both liver lobes. There was strong correlation of mebrofenin uptake with HUI for RLL (r{sup 2} = 0.802, p = 0.001) and RE for LLL (r{sup 2} = 0.704, p = 0.005) and moderate correlation with HUI for LLL (r{sup 2} = 0.560, p = 0.037) and RE for RLL (r{sup 2} = 0.620, p = 0.018). Correlating the percentage share of RLL function derived from MRI (with HUI) with the percentage of RLL function derived from mebrofenin uptake revealed a strong correlation (r{sup 2} = 0.775, p = 0.002). Both RE and HUI correlate with mebrofenin uptake in HBS. The results suggest that Gd-EOB-enhanced MRI and {sup 99m}Tc-mebrofenin HBS may equally be used to separately determine right and left liver lobe function. (orig.)

  19. Detection of hepatocellular carcinoma by Gd-EOB-DTPA-enhanced liver MRI: Comparison with triple phase 64 detector row helical CT

    International Nuclear Information System (INIS)

    Akai, Hiroyuki; Kiryu, Shigeru; Matsuda, Izuru; Satou, Jirou; Takao, Hidemasa; Tajima, Taku; Watanabe, Yasushi; Imamura, Hiroshi; Kokudo, Norihiro; Akahane, Masaaki; Ohtomo, Kuni

    2011-01-01

    Purpose: To compare the diagnostic performance of Gd-EOB-DTPA-enhanced MRI with that of triple phase 64-MDCT in the detection of hepatocellular carcinoma (HCC). Patients and methods: Thirty-four patients with 52 surgically proven lesions underwent Gd-EOB-DTPA-enhanced MRI and triple phase 64-MDCT. Two observers independently evaluated MR and CT imaging on a lesion-by-lesion basis. Sensitivity, positive and negative predictive values and reproducibility were evaluated. The diagnostic accuracy of each modality was assessed with alternative-free response receiver operating characteristic (ROC) analysis. Results: Both observers showed higher sensitivity in detecting lesions with MRI compared to CT, however, only the difference between the two imaging techniques for observer 2 was significant (P = 0.034). For lesions 1 cm or smaller, MRI and CT showed equal sensitivity (both 62.5%) with one observer, and MRI proved superior to CT with the other observer (MRI 75% vs. CT 56.3%), but the latter difference was not significant (P = 0.083). The difference in positive and negative predictive value between the two imaging techniques for each observer was not significant (P > 0.05). The areas under the ROC curve for each observer were 0.843 and 0.861 for MRI vs. 0.800 and 0.833 for CT and the differences were not significant. Reproducibility was higher using MRI for both observers, but the result was not significant (MRI 32/33 vs. CT 29/33, P = 0.083). Conclusion: Gd-EOB-DTPA-enhanced MRI tended to show higher diagnostic accuracy, sensitivity and reproducibility compared to triple phase 64-MDCT in the detection of hepatocellular carcinoma, however statistical significance was not achieved.

  20. Multivariable analysis of clinical influence factors on liver enhancement of Gd-EOB-DTPA-enhanced 3T MRI; Multivariable Analyse klinischer Einflussfaktoren auf die Signalintensitaet bei Gd-EOB-DTPA 3T-MRT der Leber

    Energy Technology Data Exchange (ETDEWEB)

    Verloh, N.; Haimerl, M.; Stroszczynski, C.; Fellner, C.; Wiggermann, P. [University Hospital Regensburg (Germany). Dept. of Radiology; Zeman, F. [University Hospital Regensburg (Germany). Center for Clinical Trials; Teufel, A. [University Hospital Regensburg (Germany). Dept. of Gastroenterology; Lang, S. [University Hospital Regensburg (Germany). Dept. of Surgery

    2015-01-15

    The purpose of this study was to identify clinical factors influencing Gd-EOB-DTPA liver uptake in patients with healthy liver parenchyma. A total of 124 patients underwent contrast-enhanced MRI with a hepatocyte-specific contrast agent at 3T. T1-weighted volume interpolated breath-hold examination (VIBE) sequences with fat suppression were acquired before and 20 minutes after contrast injection. The relative enhancement (RE) between plain and contrast-enhanced signal intensity was calculated. Simple and multiple linear regression analyses were performed to evaluate clinical factors influencing the relative enhancement. Patients were subdivided into three groups according to their relative liver enhancement (HRE, RE ≥ 100 %; MRE, 100 % > RE > 50 %; NRE, RE ≤ 50 %) and were analyzed according to the relevant risk factors. Simple regression analyses revealed patient age, transaminases (AST, ALT, GGT), liver, spleen and delta-liver volume (the difference between the volumetrically measured liver volume and the estimated liver volume based on body weight) as significant factors influencing relative enhancement. In the multiple analysis the transaminase AST, spleen and delta liver volume remained significant factors influencing relative enhancement. Delta liver volume showed a significant difference between all analyzed groups. Liver enhancement in the hepatobiliary phase depends on a variety of factors. Body weight-adapted administration of Gd-EOB-DTPA may lead to inadequate liver enhancement after 20 minutes especially when the actual liver volume differs from the expected volume.

  1. MRI enhancement of the facial nerve with Gd-DTPA, 2; Investigation of enhanced nerve portions in patients with facial palsy

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Masahiro (Kansai Medical School, Moriguchi, Osaka (Japan))

    1993-08-01

    We performed enhanced MRI using Gd-DTPA in 84 patients with facial palsy. After assessing enhancement of the normal facial nerve, we examined enhancement in patients with Bell's palsy and Ramsay Hunt syndrome. In 95% of patients with Bell's palsy, enhancement was obtained in the distal IAC and labyrinthine portions. In 72%, enhancement was significant from the distal IAC portion through the vertical portion. In some of the patients who underwent enhanced MRI twice, increased signal intensity was observed in distal portions such as the vertical portion. In many cases of Ramsay Hunt syndrome, enhancement was seen extensively in the IAC portion through the vertical portion. In the subjects with internal auditory symptoms such as vertigo and tinnitus, enhancement of the IAC portion was seen not only in the facial nerve but also in the vestibular and the cochlear nerves. These results suggest that the vascular permeability of lesions in Bell's palsy may be increased from the distal IAC portion to the vertical portion. Judging from the present findings with Ramsay Hunt syndrome, symptoms related to the enhanced portions suggest that accompanying internal auditory symptoms occur due to inflammation of the IAC portions of cochlear and vestibular nerves. (author).

  2. MRI enhancement of the facial nerve with Gd-DTPA, 2; Investigation of enhanced nerve portions in patients with facial palsy

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Masahiro [Kansai Medical School, Moriguchi, Osaka (Japan)

    1993-08-01

    We performed enhanced MRI using Gd-DTPA in 84 patients with facial palsy. After assessing enhancement of the normal facial nerve, we examined enhancement in patients with Bell's palsy and Ramsay Hunt syndrome. In 95% of patients with Bell's palsy, enhancement was obtained in the distal IAC and labyrinthine portions. In 72%, enhancement was significant from the distal IAC portion through the vertical portion. In some of the patients who underwent enhanced MRI twice, increased signal intensity was observed in distal portions such as the vertical portion. In many cases of Ramsay Hunt syndrome, enhancement was seen extensively in the IAC portion through the vertical portion. In the subjects with internal auditory symptoms such as vertigo and tinnitus, enhancement of the IAC portion was seen not only in the facial nerve but also in the vestibular and the cochlear nerves. These results suggest that the vascular permeability of lesions in Bell's palsy may be increased from the distal IAC portion to the vertical portion. Judging from the present findings with Ramsay Hunt syndrome, symptoms related to the enhanced portions suggest that accompanying internal auditory symptoms occur due to inflammation of the IAC portions of cochlear and vestibular nerves. (author).

  3. Gd-EOB-DTPA-enhanced MRI for monitoring future liver remnant function after portal vein embolization and extended hemihepatectomy: A prospective trial

    Energy Technology Data Exchange (ETDEWEB)

    Geisel, Dominik; Raabe, Philip; Hamm, Bernd; Denecke, Timm [Charite Campus Virchow-Klinikum, Department of Diagnostic and Interventional Radiology, Berlin (Germany); Luedemann, Lutz [Essen University Hospital, Department of Medical Physics, Essen (Germany); Malinowski, Maciej; Stockmann, Martin; Seehofer, Daniel; Pratschke, Johann [Charite Campus Virchow-Klinikum, Department of General, Visceral and Transplantation Surgery, Berlin (Germany)

    2017-07-15

    To evaluate changes in liver function after right portal vein embolization (PVE) and extended right hemihepatectomy using gadolinium ethoxybenzyl-DTPA-enhanced (Gd-EOB-DTPA) MRI. In this prospective trial, 37 patients undergoing PVE were examined before and 14 and 28 days after PVE and 10 days after extended hemihepatectomy using Gd-EOB-DTPA-enhanced MRI. Lobar volume, kinetic growth rate (KGR), relative enhancement (RE) as well as hepatocellular uptake index (HUI) and fat signal fraction (FSF) were calculated for each lobe. RE of the left liver lobe (LLL) was steadily increasing after PVE and decreased to 0.48 ± 0.19 10 days after surgery, which is significantly lower than 14 days and 28 days post PVE (P < 0.05). KGR was 14.06 ± 9.82%/week for the period from PVE to 14 days after PVE. HUI of the LLL increased steadily after PVE and was significantly higher at both 14 and 28 days after PVE compared to pre PVE (P < 0.05). HUI of the residual liver after surgery was lower than before. Gd-EOB-DTPA-enhanced MRI may be used to monitor the functional increase in the FLR after PVE and to depict the intraoperative liver injury leading to a decrease in liver remnant function. (orig.)

  4. Health-economic evaluation of three imaging strategies in patients with suspected colorectal liver metastases: Gd-EOB-DTPA-enhanced MRI vs. extracellular contrast media-enhanced MRI and 3-phase MDCT in Germany, Italy and Sweden

    International Nuclear Information System (INIS)

    Zech, C.J.; Grazioli, L.; Jonas, E.; Ekman, M.; Joensson, L.; Niebecker, R.; Kienbaum, S.; Gschwend, S.; Breuer, J.

    2009-01-01

    The purpose of this study was to perform an economic evaluation of hepatocyte-specific Gd-EOB-DTPA enhanced MRI (PV-MRI) compared to extracellular contrast-media-enhanced MRI (ECCM-MRI) and three-phase-MDCT as initial modalities in the work-up of patients with metachronous colorectal liver metastases. The economic evaluation was performed with a decision-tree model designed to estimate all aggregated costs depending on the initial investigation. Probabilities on the need for further imaging to come to a treatment decision were collected through interviews with 13 pairs of each a radiologist and a liver surgeon in Germany, Italy and Sweden. The rate of further imaging needed was 8.6% after initial PV-MRI, 18.5% after ECCM-MRI and 23.5% after MDCT. Considering the cost of all diagnostic work-up, intra-operative treatment changes and unnecessary surgery, a strategy starting with PV-MRI with 959 EUR was cost-saving compared to ECCM-MRI (1,123 EUR) and MDCT (1,044 EUR) in Sweden. In Italy and Germany, PV-MRI was cost-saving compared to ECCM-MRI and had total costs similar to MDCT. In conclusion, our results indicate that PV-MRI can lead to cost savings by improving pre-operative planning and decreasing intra-operative changes. The higher cost of imaging with PV-MRI is offset in such a scenario by lower costs for additional imaging and less intra-operative changes. (orig.)

  5. Multiple FNH-Like Lesions in a Patient with Chronic Budd-Chiari Syndrome: Gd-EOB-Enhanced MRI and BR1 CEUS Findings

    Directory of Open Access Journals (Sweden)

    Caroline Newerla

    2012-01-01

    Full Text Available A-26-year old female patient with chronic Budd-Chiari syndrome due to different underlying blood disorders applied for a two-year followup of the liver with Gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic-acid-(Gd-EOB-DTPA- enhanced MRI. The liver function tests were raised. Besides showing a progressive hepatosplenomegaly and a cirrhotic liver alteration, the MRI revealed multiple new nodular lesions in all liver segments. These lesions showed typical patterns in the precontrast images, while there was an arterial and a persistent portal venous enhancement. In the hepatobiliary liver-specific late phase, a central “washout” and a persistent rim enhancement were observed (target sign. The additionally performed contrast-enhanced ultrasonography showed a strong zentrifugal arterial enhancement of the lesions followed by an isoechoic enhancement in the portal venous and delayed liver phase. Histologically these lesions turned out as focal nodular hyperplasias (FNH or FNH-like lesions, also known as large regenerative nodules (LRNs. Differentiation between regenerative nodules like LRN and hepatocellular carcinoma (HCC in cirrhotic livers is crucial, and the target sign in the hepatobiliary phase of Gd-EOB-DTPA as well as the centrifugal arterial enhancement followed by an isoenhancement during a CEUS might be useful for establishing the correct diagnosis of such hypervascular lesions with proliferated and likely aberrant bile ducts.

  6. MRI for characterization of primary tumors in the non-cirrhotic liver: Added value of Gd-EOB-DTPA enhanced hepatospecific phase

    Energy Technology Data Exchange (ETDEWEB)

    Donati, Olivio F.; Hunziker, Roger; Fischer, Michael A. [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich (Switzerland); Raptis, Dimitri A.; Breitenstein, Stefan [Department of Visceral and Transplant Surgery, Swiss Hepato-Pancreato-Biliary (HPB) Center, University Hospital Zurich, Zurich (Switzerland); Patak, Michael A., E-mail: Michael.Patak@hirslanden.ch [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich (Switzerland); Clinic Hirslanden, Hirslanden Hospital Group, Zurich (Switzerland)

    2014-07-15

    Purpose: To evaluate the added value of hepatospecific phase in Gd-EOB-DTPA enhanced magnetic resonance imaging (MRI) in patients with primary tumors in non-cirrhotic liver. Methods: Twenty-nine patients (median, 39 years; range, 18–81 years; 11 male) underwent preoperative Gd-EOB-DTPA enhanced MRI including hepatospecific phase after 10 and 20 min of contrast injection at four institutions in Europe, North America and New Zealand. Images were evaluated by three different readers (R1–R3) who characterized liver tumors with and without consultation of the hepatospecific phase images. Confidence in diagnosis was scored on a visual analog scale from 1 to 10. Histopathology (adenoma, n = 5; focal nodular hyperplasia, n = 11 and hepatocellular carcinoma, n = 13) in all patients served as the standard of reference. Differences were evaluated using the McNemar and Wilcoxon signed rank test. Results: Without hepatospecific phase images available, 22 (76%), 19 (66%) and 19 (66%) of 29 tumors were characterized correctly by the three readers respectively. Mean confidence in diagnosis was 6.1, 5.7 and 5.8. With the hepatospecific phase included, characterization of liver tumors did not change significantly with 21 (72%), 23 (79%) and 19 (66%) of 29 tumors diagnosed correctly (p > 0.05). According confidence ratings increased to 6.3, 6.5 and 7.7, respectively. Increase in diagnostic confidence was significant for R2 and R3 (p < 0.05) and independent of reader's experience. Conclusion: The additional hepatospecific phase in Gd-EOB-DTPA enhanced MRI did not significantly increase diagnostic accuracy in characterization of primary tumors in the non-cirrhotic liver. However, 2/3 readers showed a significant increase in diagnostic confidence after consultation of the hepatospecific phase.

  7. Comparison of two brain tumor-localizing MRI agent. GD-BOPTA and GD-DTPA. MRI and ICP study of rat brain tumor model

    International Nuclear Information System (INIS)

    Zhang, T.; Matsumura, A.; Yamamoto, T.; Yoshida, F.; Nose, T.

    2000-01-01

    In this study, we compared the behavior of Gd-BOPTA as a brain tumor selective contrast agent with Gd-DTPA in a common dose of 0.1 mmol/kg. We performed a MRI study using those two agent as contrast material, and we measured tissue Gd-concentrations by ICP-AES. As a result, Gd-BOPTA showed a better MRI enhancement in brain tumor. ICP showed significantly greater uptake of Gd-BOPTA in tumor samples, at all time course peaked at 5 minutes after administration, Gd being retained for a longer time in brain tumor till 2 hours, without rapid elimination as Gd-DTPA. We conclude that Gd-BOPTA is a new useful contrast material for MR imaging in brain tumor and an effective absorption agent for neutron capture therapy for further research. (author)

  8. Improved parenchymal liver enhancement with extended delay on Gd-EOB-DTPA-enhanced MRI in patients with parenchymal liver disease: associated clinical and imaging factors

    International Nuclear Information System (INIS)

    Esterson, Y.B.; Flusberg, M.; Oh, S.; Mazzariol, F.; Rozenblit, A.M.; Chernyak, V.

    2015-01-01

    Aim: To establish the effect of prolonged hepatobiliary phase (HBP) delay time on hepatic enhancement in patients with parenchymal liver disease (PLD). Materials and methods: Gadoxetate disodium (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) examinations with HBP were obtained after 20- (HBP-20) and 30-minute (HBP-30) delays in patients with PLD. For each patient, the Model for End-Stage Liver Disease (MELD) score, total and direct bilirubin, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), prothrombin time (PT), and partial thromboplastin time (PTT) were recorded. Signal intensities of the liver, main portal vein, and spleen on pre-contrast, HBP-20, and HBP-30 were documented. Signal intensities were used to calculate liver relative enhancement (LRE), liver–spleen index (LSI), and liver–portal vein index (LPI) for HBP-20 and HBP-30. Improved hepatic enhancement was considered if two or more indices were higher on HBP-30 than HBP-20. A logistic regression model was constructed with improved hepatic enhancement as the outcome. Results: One hundred and twenty-nine patients underwent 142 MRIs. Mean LRE, LSI, and LPI each increased from HBP-20 to HBP-30 (p = 0.004, p < 0.001, and p < 0.001, respectively). Seventy-two point five percent of cases demonstrated improved hepatic enhancement. The odds ratios for improved hepatic enhancement were 0.85 for MELD score (p = 0.02) and 3.2 for the 3 T scanner (p = 0.02), adjusted for age and sex. Conclusion: Increasing HBP delay to 30 minutes improves hepatic enhancement in patients with PLD, particularly if using a 3 T scanner. This effect is attenuated with higher MELD scores. -- Highlights: •Increasing hepatobiliary phase delay improves hepatic enhancement in liver disease. •This effect is enhanced if using a 3T scanner. •This effect is attenuated with higher MELD scores

  9. Gd-EOB-DTPA-enhanced 3.0-Tesla MRI findings for the preoperative detection of focal liver lesions: Comparison with iodine-enhanced multi-detector computed tomography

    Science.gov (United States)

    Park, Hyong-Hu; Goo, Eun-Hoe; Im, In-Chul; Lee, Jae-Seung; Kim, Moon-Jib; Kwak, Byung-Joon; Chung, Woon-Kwan; Dong, Kyung-Rae

    2012-12-01

    The safety of gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid (Gd-EOB-DTPA) has been confirmed, but more study is needed to assess the diagnostic accuracy of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) in patients with a hepatocellular carcinoma (HCC) for whom surgical treatment is considered or with a metastatic hepatoma. Research is also needed to examine the rate of detection of hepatic lesions compared to multi-detector computed tomography (MDCT), which is used most frequently to localize and characterize a HCC. Gd-EOB-DTPA-enhanced MRI and iodine-enhanced MDCT imaging were compared for the preoperative detection of focal liver lesions. The clinical usefulness of each method was examined. The current study enrolled 79 patients with focal liver lesions who preoperatively underwent MRI and MDCT. In these patients, there was less than one month between the two diagnostic modalities. Imaging data were taken before and after contrast enhancement in both methods. To evaluate the images, we analyzed the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) in the lesions and the liver parenchyma. To compare the sensitivity of the two methods, we performed a quantitative analysis of the percentage signal intensity of the liver (PSIL) on a high resolution picture archiving and communication system (PACS) monitor (paired-samples t-test, p DTPA-enhanced MRI findings and the iodine-enhanced MDCT by using an adjusted x2 test. The SNRs, CNRs, and PSIL all had a greater detection rate in Gd-EOB-DTPA enhanced MRI than in iodine-enhanced MDCT. Hepatocyte-selective uptake was observed 20 minutes after the injection in the focal nodular hyperplasia (FNH, 9/9), adenoma (9/10), and highly-differentiated HCC (grade G1, 27/30). Rim enhancement was detected in all metastases (30/30). During the arterial and the delayed phases, good overall agreement between the gadoxetic-acid-enhanced MR and CT was observed (x2 test, p DTPA-enhanced MRI had a higher

  10. Gd-EOB-DTPA-enhanced magnetic resonance imaging features of hepatic hemangioma compared with enhanced computed tomography

    OpenAIRE

    Tateyama, Akihiro; Fukukura, Yoshihiko; Takumi, Koji; Shindo, Toshikazu; Kumagae, Yuichi; Kamimura, Kiyohisa; Nakajo, Masayuki

    2012-01-01

    AIM: To clarify features of hepatic hemangiomas on gadolinium-ethoxybenzyl-diethylenetriaminpentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) compared with enhanced computed tomography (CT).

  11. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

    Energy Technology Data Exchange (ETDEWEB)

    Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi [Jichi Medical School, Minamikawachi, Tochigi (Japan)

    2001-07-01

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

  12. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

    International Nuclear Information System (INIS)

    Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi

    2001-01-01

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

  13. Gd-DTPA in MRI. Clinical experience in intracranial pathologies

    Energy Technology Data Exchange (ETDEWEB)

    Bradac, G B; Riva, A; Berger, T; Stura, G; Duca, S

    1988-01-01

    Sixty-seven patients with various intracranial pathologies were studied using Gd-DTPA as a contrast medium applied to MRI. This paramagnetic substance was well tolerated by all patients, and proved particularly useful in improving the diagnosis of extra-axial tumors, in which a rich enhancement was always present. Gd-DTPA allowed a better definition of the tumor outlines, as well as its differentiation from edema, and the demonstration of its relationship to brain parenchyma and cerebral vessels. This was particularly true for meningiomas, which often display poor contrast enhancement at MRI. Even though acoustic neuromas had, as a rule, high signal intensity, Gd-DTPA was useful to precisely recognise the intracanalar part of the tumor. The value of Gd-DTPA was less evident in intra-axial lesions. It proved nonetheless useful in demonstrating the portions of the tumor where, due to alterations in BBB, enhancement was present. This allowed both to characterized the lesion and to perform accurate biopsies.

  14. Usefulness of fat-suppressed Gd-enhanced MR imaging of tongue cancer

    International Nuclear Information System (INIS)

    Murakami, Shumei; Fuchihata, Hajime; Yoon, Sukja; Furukawa, Souhei; Kawai, Tadahiko; Kishino, Mitsunobu

    1999-01-01

    To evaluate the usefulness of the fat suppression technique for magnetic resonance imaging of oral tongue cancer. One hundred and fourteen patients underwent both magnetic resonance imaging (MRI) and computed tomography (CT). All patients were clinically diagnosed as having oral tongue cancer shown to be squamous cell carcinoma histopathologically. We used two types of CT and six types of MRI scanning: plain CT, contrast enhanced CT, conventional T1w, conventional PDw, conventional T2w, fat-suppressed (FATS) T1w, Gd-enhanced conventional T1w, and Gd-enhanced FATS T1w images. The focus of our study was Gd-enhanced FATS T1w imaging. Tumor detection rates were as follows: Gd-enhanced FATS T1w MRI, 86.8%; conventional T2w MRI, 71.9%; conventional PDw MRI, 65.8%; Gd-enhanced conventional T1w MRI, 47.4%; contrast enhanced CT, 36.8%; T1w MRI, 20.2%; CT, 10.5%. There were 59 cases in which tumors were detected by Gd-enhanced FATS T1w MRI but not detected by contrast enhanced CT. Gd-enhanced FATS T1w MRI was the best for the tumor detection and Gd-enhanced conventional T1w MRI was not useful in the diagnosis of the tongue cancer. CT imaging must not be the first choice for tumor detection in tongue cancer patients. (author)

  15. In vivo transport of Gd-DTPA2- into human meniscus and cartilage assessed with delayed gadolinium-enhanced MRI of cartilage (dGEMRIC)

    Science.gov (United States)

    2014-01-01

    Background Impaired stability is a risk factor in knee osteoarthritis (OA), where the whole joint and not only the joint cartilage is affected. The meniscus provides joint stability and is involved in the early pathological progress of OA. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) has been used to identify pre-radiographic changes in the cartilage in OA, but has been used less commonly to examine the meniscus, and then using only a double dose of the contrast agent. The purpose of this study was to enable improved early OA diagnosis by investigate the temporal contrast agent distribution in the meniscus and femoral cartilage simultaneously, in healthy volunteers, using 3D dGEMRIC at two different doses of the contrast agent Gd-DTPA2-. Methods The right knee in 12 asymptomatic volunteers was examined using a 3D Look-Locker sequence on two occasions after an intravenous injection of a double or triple dose of Gd-DTPA2- (0.2 or 0.3 mmol/kg body weight). The relaxation time (T1) and relaxation rate (R1 = 1/T1) were measured in the meniscus and femoral cartilage before, and 60, 90, 120 and 180 minutes after injection, and the change in relaxation rate (ΔR1) was calculated. Paired t-test and Analysis of Variance (ANOVA) were used for statistical evaluation. Results The triple dose yielded higher concentrations of Gd-DTPA2- in the meniscus and cartilage than the double dose, but provided no additional information. The observed patterns of ΔR1 were similar for double and triple doses of the contrast agent. ΔR1 was higher in the meniscus than in femoral cartilage in the corresponding compartments at all time points after injection. ΔR1 increased until 90-180 minutes in both the cartilage and the meniscus (p meniscus at all time points (p meniscus, than in the avascular central part of the posterior medial meniscus during the first 60 minutes (p meniscus and cartilage simultaneously using dGEMRIC, preferably 90 minutes after the injection of a

  16. Dynamic Gd-DTPA enhanced breath-hold 1.5 t MRI of normal lungs and patients with interstitial lung disease and pulmonary nodules: preliminary results

    International Nuclear Information System (INIS)

    Semelka, R.C.; Maycher, B.; Shoenut, J.P.; Kroeker, R.; Griffin, P.; Lertzman, M.

    1992-01-01

    A FLASH technique was used, which encompassed the entire thorax in the transverse plane, before and after dynamic intravenous injection of godalinium DTPA (Gd-DTPA) to study 7 patients with normal lungs, 12 patients with interstitial lung disease (ILD), and 11 patients with pulmonary nodules. Comparative CT studies were obtained within 2 weeks of the MRI study in the patients with lung disease. Quantitative signal intensity (SI) measurements were performed. Qualitative evaluation of lung parenchyma was determined in a prospective blinded fashion, and in the normal group comparison was made with the CT images. In normal patients, SI of lung parenchyma increased by 7.7±1.3%. On precontrast images, second-order pulmonary branchings were visible while post-contrast, fifth- to sixth-order branches were apparent. In patients with ILD, interstitial changes enhanced to a variable extent, increases in SI ranging from minimal (49.9%) to substantial (308.4%). Detection of pulmonary nodules improved following contrast injection. The minimum lesion size detectable decreased from 8 mm precontrast to 5 mm post-contrast. Percentage contrast enhancement was greater for malignant nodules (124.2±79.7%) than benign nodules (5.8±4.7%) (p<0.01). (orig.)

  17. Health economic assessment of Gd-EOB-DTPA MRI versus ECCM-MRI and multi-detector CT for diagnosis of hepatocellular carcinoma in China

    Science.gov (United States)

    He, Xiaoning; Holtorf, Anke-Peggy; Rinde, Harald; Xie, Shuangshuang; Shen, Wen; Hou, Jiancun; Li, Xuehua; Li, Ziping; Lai, Jiaming; Wang, Yuting; Zhang, Lin; Wang, Jian; Li, Xuesong; Ma, Kuansheng; Ye, Feng; Ouyang, Han; Zhao, Hong

    2018-01-01

    Limited data exists in China on the comparative cost of gadolinium ethoxybenzyl diethylenetriamine magnetic resonance imaging (Gd-EOB-DTPA-MRI) with other imaging techniques. This study compared the total cost of Gd-EOB-DTPA-MRI with multidetector computed tomography (MDCT) and extracellular contrast media–enhanced MRI (ECCM-MRI) as initial imaging procedures in patients with suspected hepatocellular carcinoma (HCC). We developed a decision-tree model on the basis of the Chinese clinical guidelines for HCC, which was validated by clinical experts from China. The model compared the diagnostic accuracy and costs of alternative initial imaging procedures. Compared with MDCT and ECCM-MRI, Gd-EOB-DTPA-MRI imaging was associated with higher rates of diagnostic accuracy, i.e. higher proportions of true positives (TP) and true negatives (TN) with lower false positives (FP). Total diagnosis and treatment cost per patient after the initial Gd-EOB-DTPA-MRI evaluation was similar to MDCT (¥30,360 vs. ¥30,803) and lower than that reported with ECCM-MRI (¥30,360 vs. ¥31,465). Lower treatment cost after initial Gd-EOB-DTPA-MRI was driven by reduced utilization of confirmatory diagnostic procedures and unnecessary treatments. The findings reported that Gd-EOB-DTPA-MRI offered higher diagnostic accuracy compared with MDCT and ECCM-MRI at a comparable cost, which indicates Gd-EOB-DTPA-MRI could be the preferred initial imaging procedure for the diagnosis of HCC in China. PMID:29324837

  18. Quantitative in vivo assessment of radiation injury of the liver using Gd-EOB-DTPA enhanced MRI: tolerance dose of small liver volumes

    Directory of Open Access Journals (Sweden)

    Pech Maciej

    2011-04-01

    Full Text Available Abstract Backround Hepatic radiation toxicity restricts irradiation of liver malignancies. Better knowledge of hepatic tolerance dose is favourable to gain higher safety and to optimize radiation regimes in radiotherapy of the liver. In this study we sought to determine the hepatic tolerance dose to small volume single fraction high dose rate irradiation. Materials and methods 23 liver metastases were treated by CT-guided interstitial brachytherapy. MRI was performed 3 days, 6, 12 and 24 weeks after therapy. MR-sequences were conducted with T1-w GRE enhanced by hepatocyte-targeted Gd-EOB-DTPA. All MRI data sets were merged with 3D-dosimetry data. The reviewer indicated the border of hypointensity on T1-w images (loss of hepatocyte function or hyperintensity on T2-w images (edema. Based on the volume data, a dose-volume-histogram was calculated. We estimated the threshold dose for edema or function loss as the D90, i.e. the dose achieved in at least 90% of the pseudolesion volume. Results At six weeks post brachytherapy, the hepatocyte function loss reached its maximum extending to the former 9.4Gy isosurface in median (i.e., ≥9.4Gy dose exposure led to hepatocyte dysfunction. After 12 and 24 weeks, the dysfunctional volume had decreased significantly to a median of 11.4Gy and 14Gy isosurface, respectively, as a result of repair mechanisms. Development of edema was maximal at six weeks post brachytherapy (9.2Gy isosurface in median, and regeneration led to a decrease of the isosurface to a median of 11.3Gy between 6 and 12 weeks. The dose exposure leading to hepatocyte dysfunction was not significantly different from the dose provoking edema. Conclusion Hepatic injury peaked 6 weeks after small volume irradiation. Ongoing repair was observed up to 6 months. Individual dose sensitivity may differ as demonstrated by a relatively high standard deviation of threshold values in our own as well as all other published data.

  19. Novel Gd nanoparticles enhance vascular contrast for high-resolution magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Tot Bui

    2010-09-01

    Full Text Available Gadolinium (Gd, with its 7 unpaired electrons in 4f orbitals that provide a very large magnetic moment, is proven to be among the best agents for contrast enhanced MRI. Unfortunately, the most potent MR contrast agent based on Gd requires relatively high doses of Gd. The Gd-chelated to diethylene-triamine-penta-acetic acid (DTPA, or other derivatives (at 0.1 mmole/kg recommended dose, distribute broadly into tissues and clear through the kidney. These contrast agents carry the risk of Nephrogenic Systemic Fibrosis (NSF, particularly in kidney impaired subjects. Thus, Gd contrast agents that produce higher resolution images using a much lower Gd dose could address both imaging sensitivity and Gd safety.To determine whether a biocompatible lipid nanoparticle with surface bound Gd can improve MRI contrast sensitivity, we constructed Gd-lipid nanoparticles (Gd-LNP containing lipid bound DTPA and Gd. The Gd-LNP were intravenously administered to rats and MR images collected. We found that Gd in Gd-LNP produced a greater than 33-fold higher longitudinal (T(1 relaxivity, r(1, constant than the current FDA approved Gd-chelated contrast agents. Intravenous administration of these Gd-LNP at only 3% of the recommended clinical Gd dose produced MRI signal-to-noise ratios of greater than 300 in all vasculatures. Unlike current Gd contrast agents, these Gd-LNP stably retained Gd in normal vasculature, and are eliminated predominately through the biliary, instead of the renal system. Gd-LNP did not appear to accumulate in the liver or kidney, and was eliminated completely within 24 hrs.The novel Gd-nanoparticles provide high quality contrast enhanced vascular MRI at 97% reduced dose of Gd and do not rely on renal clearance. This new agent is likely to be suitable for patients exhibiting varying degrees of renal impairment. The simple and adaptive nanoparticle design could accommodate ligand or receptor coating for drug delivery optimization and in vivo drug

  20. Gd-EOB-DTPA-enhanced magnetic resonance imaging for bile duct intraductal papillary mucinous neoplasms

    OpenAIRE

    Ying, Shi-Hong; Teng, Xiao-Dong; Wang, Zhao-Ming; Wang, Qi-Dong; Zhao, Yi-Lei; Chen, Feng; Xiao, Wen-Bo

    2015-01-01

    AIM: To investigate gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) of intraductal papillary mucinous neoplasms of the bile duct (IPMN-B).

  1. Feasibility of gadoteric acid for delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) at the wrist and knee and comparison with Gd-DTPA.

    Science.gov (United States)

    Rehnitz, Christoph; Klaan, Bastian; Do, Thuy; Barié, Alexander; Kauczor, Hans-Ulrich; Weber, Marc-André

    2017-11-01

    To assess the feasibility of gadoteric acid for delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and to compare the dGEMRIC values obtained using gadoteric acid with those obtained by an equimolar dose of Gd-DTPA. At 3T, dGEMRIC of the wrist was performed twice using a T 1 -weighted 3D-volumetric interpolated breath-hold examination sequence in 16 healthy volunteers (10 women; mean age 26.0 years) using gadoteric acid first and Gd-DTPA 3 weeks later. In addition, 24 patients with knee pain were examined using gadoteric acid (n = 12; seven women; mean age 45.8 years) or Gd-DTPA (n = 12; four women; mean age 47.1 years). T 1 values, the relative decrease in T 1 , and the delta R1 were compared using t-tests. Interobserver agreement was assessed using the intraclass correlation (ICC) between two independent readers. At the wrist, there was no significant difference in delta R1 values (0.34 ± 0.10/s, 95% confidence interval [0.30;0.38]/s for gadoteric acid and 0.32 ± 0.09 [0.29;0.35]/s for Gd-DTPA, P = 0.24) or the relative decrease in T 1 (0.25 ± 0.06 [0.29;0.35] msec for gadoteric acid and 0.24 ± 0.05 [0.22;0.27] msec for Gd-DTPA, P = 0.35). High observer agreement was found at precontrast (ICC = 0.87, P DTPA, P = 0.59) or the relative decrease in T 1 (0.30 ± 0.10 [0.26;0.34] msec for gadoteric acid and 0.33 ± 0.05 [0.30;0.35] msec for Gd-DTPA, P = 0.28). High ICCs of 0.96 (P DTPA. 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1433-1440. © 2017 International Society for Magnetic Resonance in Medicine.

  2. Aiming for a simpler early arthritis MRI protocol: can Gd contrast administration be eliminated?

    Energy Technology Data Exchange (ETDEWEB)

    Stomp, Wouter; Bloem, Johan L.; Reijnierse, Monique [Leiden University Medical Center, Department of Radiology, P.O. Box 9600, Leiden (Netherlands); Krabben, Annemarie; Heijde, Desiree van der; Huizinga, Tom W.J.; Helm-van Mil, Annette H.M. van der [Leiden University Medical Center, Department of Rheumatology, P.O. Box 9600, Leiden (Netherlands); Oestergaard, Mikkel [University of Copenhagen, Copenhagen Center for Arthritis Research, Center for Rheumatology and Spinal Diseases, Glostrup Hospital, Glostrup (Denmark)

    2015-05-01

    To evaluate whether intravenous gadolinium (Gd) contrast administration can be eliminated when evaluating synovitis and tenosynovitis in early arthritis patients, thereby decreasing imaging time, cost, and invasiveness. Wrist MRIs of 93 early arthritis patients were evaluated by two readers for synovitis of the radioulnar, radiocarpal, and intercarpal joints, according to the Rheumatoid Arthritis MRI Scoring method (RAMRIS), and for tenosynovitis in ten compartments. Scores of MRI images without Gd contrast enhancement were compared to scores obtained when evaluating all, including contrast-enhanced, MRI images as reference. Subsequently, a literature review and pooled analysis of data from the present and two previous studies were performed. At the individual joint/tendon level, sensitivity to detect synovitis without Gd contrast was 91 % and 72 % for the two readers, respectively, with a specificity of 51 % and 81 %. For tenosynovitis, the sensitivity was 67 % and 54 %, respectively, with a specificity of 87 % and 91 %. Pooled data analysis revealed an overall sensitivity of 81 % and specificity of 50 % for evaluation of synovitis. Variations in tenosynovitis scoring systems hindered pooled analyses. Eliminating Gd contrast administration resulted in low specificity for synovitis and low sensitivity for tenosynovitis, indicating that Gd contrast administration remains essential for an optimal assessment. (orig.)

  3. Aiming for a simpler early arthritis MRI protocol: can Gd contrast administration be eliminated?

    International Nuclear Information System (INIS)

    Stomp, Wouter; Bloem, Johan L.; Reijnierse, Monique; Krabben, Annemarie; Heijde, Desiree van der; Huizinga, Tom W.J.; Helm-van Mil, Annette H.M. van der; Oestergaard, Mikkel

    2015-01-01

    To evaluate whether intravenous gadolinium (Gd) contrast administration can be eliminated when evaluating synovitis and tenosynovitis in early arthritis patients, thereby decreasing imaging time, cost, and invasiveness. Wrist MRIs of 93 early arthritis patients were evaluated by two readers for synovitis of the radioulnar, radiocarpal, and intercarpal joints, according to the Rheumatoid Arthritis MRI Scoring method (RAMRIS), and for tenosynovitis in ten compartments. Scores of MRI images without Gd contrast enhancement were compared to scores obtained when evaluating all, including contrast-enhanced, MRI images as reference. Subsequently, a literature review and pooled analysis of data from the present and two previous studies were performed. At the individual joint/tendon level, sensitivity to detect synovitis without Gd contrast was 91 % and 72 % for the two readers, respectively, with a specificity of 51 % and 81 %. For tenosynovitis, the sensitivity was 67 % and 54 %, respectively, with a specificity of 87 % and 91 %. Pooled data analysis revealed an overall sensitivity of 81 % and specificity of 50 % for evaluation of synovitis. Variations in tenosynovitis scoring systems hindered pooled analyses. Eliminating Gd contrast administration resulted in low specificity for synovitis and low sensitivity for tenosynovitis, indicating that Gd contrast administration remains essential for an optimal assessment. (orig.)

  4. Gd-DTPA-enhanced dynamic MR imaging

    International Nuclear Information System (INIS)

    Frank, J.A.; Choyke, P.L.; Carvlin, M.; Inscoe, S.; Austin, H.; Dwyer, A.J.; Girton, M.; Black, J.

    1988-01-01

    This paper describes dynamic enhanced renal MR imaging, a new method of identifying specific derangements in renal function. Various diuretics were employed in 45 animal experiments to demonstrate the effects on the normal renal enhancement pattern (EP) after Gd-DTPA. Since different diuretics, osmotic (O), carbonic anhydrase (CA), and loop (L), are active at different sites, specific EP alterations are observed. Imaging was performed with 32 5.1-second sequential gradient recalled acquisition in a steady state images following a bolus of Gd-DTPA

  5. Health economic assessment of Gd-EOB-DTPA MRI versus ECCM-MRI and multi-detector CT for diagnosis of hepatocellular carcinoma in China.

    Directory of Open Access Journals (Sweden)

    Xiaoning He

    Full Text Available Limited data exists in China on the comparative cost of gadolinium ethoxybenzyl diethylenetriamine magnetic resonance imaging (Gd-EOB-DTPA-MRI with other imaging techniques. This study compared the total cost of Gd-EOB-DTPA-MRI with multidetector computed tomography (MDCT and extracellular contrast media-enhanced MRI (ECCM-MRI as initial imaging procedures in patients with suspected hepatocellular carcinoma (HCC. We developed a decision-tree model on the basis of the Chinese clinical guidelines for HCC, which was validated by clinical experts from China. The model compared the diagnostic accuracy and costs of alternative initial imaging procedures. Compared with MDCT and ECCM-MRI, Gd-EOB-DTPA-MRI imaging was associated with higher rates of diagnostic accuracy, i.e. higher proportions of true positives (TP and true negatives (TN with lower false positives (FP. Total diagnosis and treatment cost per patient after the initial Gd-EOB-DTPA-MRI evaluation was similar to MDCT (¥30,360 vs. ¥30,803 and lower than that reported with ECCM-MRI (¥30,360 vs. ¥31,465. Lower treatment cost after initial Gd-EOB-DTPA-MRI was driven by reduced utilization of confirmatory diagnostic procedures and unnecessary treatments. The findings reported that Gd-EOB-DTPA-MRI offered higher diagnostic accuracy compared with MDCT and ECCM-MRI at a comparable cost, which indicates Gd-EOB-DTPA-MRI could be the preferred initial imaging procedure for the diagnosis of HCC in China.

  6. Non-invasive breast biopsy method using GD-DTPA contrast enhanced MRI series and F-18-FDG PET/CT dynamic image series

    Science.gov (United States)

    Magri, Alphonso William

    This study was undertaken to develop a nonsurgical breast biopsy from Gd-DTPA Contrast Enhanced Magnetic Resonance (CE-MR) images and F-18-FDG PET/CT dynamic image series. A five-step process was developed to accomplish this. (1) Dynamic PET series were nonrigidly registered to the initial frame using a finite element method (FEM) based registration that requires fiducial skin markers to sample the displacement field between image frames. A commercial FEM package (ANSYS) was used for meshing and FEM calculations. Dynamic PET image series registrations were evaluated using similarity measurements SAVD and NCC. (2) Dynamic CE-MR series were nonrigidly registered to the initial frame using two registration methods: a multi-resolution free-form deformation (FFD) registration driven by normalized mutual information, and a FEM-based registration method. Dynamic CE-MR image series registrations were evaluated using similarity measurements, localization measurements, and qualitative comparison of motion artifacts. FFD registration was found to be superior to FEM-based registration. (3) Nonlinear curve fitting was performed for each voxel of the PET/CT volume of activity versus time, based on a realistic two-compartmental Patlak model. Three parameters for this model were fitted; two of them describe the activity levels in the blood and in the cellular compartment, while the third characterizes the washout rate of F-18-FDG from the cellular compartment. (4) Nonlinear curve fitting was performed for each voxel of the MR volume of signal intensity versus time, based on a realistic two-compartment Brix model. Three parameters for this model were fitted: rate of Gd exiting the compartment, representing the extracellular space of a lesion; rate of Gd exiting a blood compartment; and a parameter that characterizes the strength of signal intensities. Curve fitting used for PET/CT and MR series was accomplished by application of the Levenburg-Marquardt nonlinear regression

  7. Primed infusion with delayed equilibrium of Gd.DTPA for enhanced imaging of small pulmonary metastases.

    Science.gov (United States)

    Kalber, Tammy L; Campbell-Washburn, Adrienne E; Siow, Bernard M; Sage, Elizabeth; Price, Anthony N; Ordidge, Katherine L; Walker-Samuel, Simon; Janes, Sam M; Lythgoe, Mark F

    2013-01-01

    To use primed infusions of the magnetic resonance imaging (MRI) contrast agent Gd.DTPA (Magnevist), to achieve an equilibrium between blood and tissue (eqMRI). This may increase tumor Gd concentrations as a novel cancer imaging methodology for the enhancement of small tumor nodules within the low signal-to-noise background of the lung. A primed infusion with a delay before equilibrium (eqMRI) of the Gd(III) chelator Gd.DTPA, via the intraperitoneal route, was used to evaluate gadolinium tumor enhancement as a function of a bolus injection, which is applied routinely in the clinic, compared to gadolinium maintained at equilibrium. A double gated (respiration and cardiac) spin-echo sequence at 9.4T was used to evaluate whole lungs pre contrast and then at 15 (representative of bolus enhancement), 25 and 35 minutes (representative of eqMRI). This was carried out in two lung metastasis models representative of high and low tumor cell seeding. Lungs containing discrete tumor nodes where inflation fixed and taken for haematoxylin and eosin staining as well as CD34 staining for correlation to MRI. We demonstrate that sustained Gd enhancement, afforded by Gd equilibrium, increases the detection of pulmonary metastases compared to bolus enhancement and those tumors which enhance at equilibrium are sub-millimetre in size (<0.7 mm(2)) with a similar morphology to early bronchoalveolar cell carcinomas. As Gd-chelates are routinely used in the clinic for detecting tumors by MRI, this methodology is readily transferable to the clinic and advances MRI as a methodology for the detection of small pulmonary tumors.

  8. Biliary enhanced MR imaging by Gd-DTPA

    International Nuclear Information System (INIS)

    Ohkawa, Shinichi; Fujikura, Yuji; Kanai, Toshio; Hiramatsu, Kyoichi.

    1992-01-01

    Biliary enhanced MRI (BEMRI) by Gd-DTPA via PTCD and/or PTGBD tube for obstructive jaundice was performed in 8 patients. In all cases, biliary tract was clearly visualised as high signal intensity on T1 weighted images. On same images, primary lesion such as common bile duct cancer was also visualised as well as portal system. In addition, MR angiography (MRA) by 2D-time of flight method was performed. MRA with BEMRI shows portal encasement on the same image as biliary tract obstruction. This suggests MRA with BEMRI may replace the other modality for obstructive jaundice. (author)

  9. Correlation between choline level and Gd-DTPA enhancement in patients with brain metastases of mammary carcinoma

    NARCIS (Netherlands)

    P.E. Sijens (Paul); P. van Dijk (Pieter); M. Oudkerk (Matthijs)

    1994-01-01

    textabstractSingle voxel 1HH double spin-echo MR spectroscopy was used to examine 15 cases of brain metastasis of mammary carcinoma (18 lesions) in relation to Gd-DTPA enhanced MR imaging. For lesions larger than 50% of MRS voxel size, there was significant correlation between Gd-DTPA-enhanced MRI

  10. Improved tumor-targeting MRI contrast agents: Gd(DOTA) conjugates of a cycloalkane-based RGD peptide

    International Nuclear Information System (INIS)

    Park, Ji-Ae; Lee, Yong Jin; Ko, In Ok; Kim, Tae-Jeong; Chang, Yongmin; Lim, Sang Moo; Kim, Kyeong Min; Kim, Jung Young

    2014-01-01

    Highlights: • Development of improved tumor-targeting MRI contrast agents. • To increase the targeting ability of RGD, we developed cycloalkane-based RGD peptides. • Gd(DOTA) conjugates of cycloalkane-based RGD peptide show improved tumor signal enhancement in vivo MR images. - Abstract: Two new MRI contrast agents, Gd-DOTA-c(RGD-ACP-K) (1) and Gd-DOTA-c(RGD-ACH-K) (2), which were designed by incorporating aminocyclopentane (ACP)- or aminocyclohexane (ACH)-carboxylic acid into Gd-DOTA (gadolinium-tetraazacyclo dodecanetetraacetic acid) and cyclic RGDK peptides, were synthesized and evaluated for tumor-targeting ability in vitro and in vivo. Binding affinity studies showed that both 1 and 2 exhibited higher affinity for integrin receptors than cyclic RGDyK peptides, which were used as a reference. These complexes showed high relaxivity and good stability in human serum and have the potential to improve target-specific signal enhancement in vivo MR images

  11. Improved tumor-targeting MRI contrast agents: Gd(DOTA) conjugates of a cycloalkane-based RGD peptide

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji-Ae, E-mail: jpark@kirams.re.kr [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yong Jin; Ko, In Ok [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Tae-Jeong; Chang, Yongmin [Institute of Biomedical Engineering, Kyungpook National University, Daegu (Korea, Republic of); Lim, Sang Moo [Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Kyeong Min [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Jung Young, E-mail: jykim@kirams.re.kr [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2014-12-12

    Highlights: • Development of improved tumor-targeting MRI contrast agents. • To increase the targeting ability of RGD, we developed cycloalkane-based RGD peptides. • Gd(DOTA) conjugates of cycloalkane-based RGD peptide show improved tumor signal enhancement in vivo MR images. - Abstract: Two new MRI contrast agents, Gd-DOTA-c(RGD-ACP-K) (1) and Gd-DOTA-c(RGD-ACH-K) (2), which were designed by incorporating aminocyclopentane (ACP)- or aminocyclohexane (ACH)-carboxylic acid into Gd-DOTA (gadolinium-tetraazacyclo dodecanetetraacetic acid) and cyclic RGDK peptides, were synthesized and evaluated for tumor-targeting ability in vitro and in vivo. Binding affinity studies showed that both 1 and 2 exhibited higher affinity for integrin receptors than cyclic RGDyK peptides, which were used as a reference. These complexes showed high relaxivity and good stability in human serum and have the potential to improve target-specific signal enhancement in vivo MR images.

  12. Gadolinium-DTPA enhanced MRI of the brain

    International Nuclear Information System (INIS)

    Hosten, N.; Felix, R.

    1994-01-01

    The text reviews MRI findings in a variety of cerebral diseases. Advantages of Gadolinium-DTPA (Gd-DTPA) enhanced MRI over plain MRI and enhanced CT are discussed. Enhanced MRI is far superior to enhanced CT in the detection of meningeal tumor spread, meningeal inflammation, inflammatory lesions of the optic nerve, brain lesions in multiple sclerosis and infarction. Enhanced MRI is today the most sensitive diagnostic tool in hypophaseal adenomas. Also enhancement of gliomas is detected by MRI with higher sensitivity than by CT. Use Gd-DTPA allow to separate of vital tumor tissue from necrosis and edema, improve delineation of tumor extension and improve detection of lesions localized in gray matter

  13. Detection of hepatocellular carcinoma: comparison of Gd-DTPA- and ferumoxides-enhanced MR imaging

    International Nuclear Information System (INIS)

    Simon, G.; Link, T.M.; Daldrup-Link, H.; Settles, M.; Woertler, K.; Doebereiner, F.; Schulte-Frohlinde, E.; Rummeny, E.J.

    2005-01-01

    The aim was to compare the diagnostic performance of dynamic Gd-DTPA- and ferumoxides-enhanced MRI for hepatocellular carcinoma (HCC). Twenty-five patients with chronic hepatitis or liver cirrhosis underwent both dynamic gadopentetate- and ferumoxides-enhanced MRI studies of the liver for HCC detection on the same day. MR data of both studies were retrospectively and independently analyzed. Two observers determined in consensus the grade of diffuse fibrotic liver changes (mild, moderate or severe) and the number of focal lesions. HCCs were confirmed by histology (n=22) and/or follow-up studies for at least six months (n=64). Differences in results obtained from both MR data sets were tested for significance with the McNemar's test (p 0.05) and Gd-DTPA-enhanced scans (94.2%). Gd-DTPA- and ferumoxides-enhanced MRI perform equally well for HCC detection. The majority of small hypervascular hepatic lesions, detected on dynamic Gd-DTPA-enhanced MRI but not on ferumoxides-enhanced MRI, represent no HCCs. (orig.)

  14. Gd-HOPO Based High Relaxivity MRI Contrast Agents

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Ankona; Raymond, Kenneth

    2008-11-06

    Tris-bidentate HOPO-based ligands developed in our laboratory were designed to complement the coordination preferences of Gd{sup 3+}, especially its oxophilicity. The HOPO ligands provide a hexadentate coordination environment for Gd{sup 3+} in which all he donor atoms are oxygen. Because Gd{sup 3+} favors eight or nine coordination, this design provides two to three open sites for inner-sphere water molecules. These water molecules rapidly exchange with bulk solution, hence affecting the relaxation rates of bulk water olecules. The parameters affecting the efficiency of these contrast agents have been tuned to improve contrast while still maintaining a high thermodynamic stability for Gd{sup 3+} binding. The Gd- HOPO-based contrast agents surpass current commercially available agents ecause of a higher number of inner-sphere water molecules, rapid exchange of inner-sphere water molecules via an associative mechanism, and a long electronic relaxation time. The contrast enhancement provided by these agents is at least twice that of commercial contrast gents, which are based on polyaminocarboxylate ligands.

  15. Degeneration of uterine leiomyoma: comparison between Gd-DTPA enhanced MR imaging and pathologic findings

    International Nuclear Information System (INIS)

    Shin, M. J.; Kim, G. W.; No, T. Y.; Ahn, W. H.; Baik, S. K.; Kim, B. G.; Choi, H. Y.; Paik, O. J.

    1995-01-01

    Gonadotropin-releasing hormone(GnRH) analogues have been used as a conservative or preoperative therapy in the treatment of uterine leiomyoma. Since these drugs, which can induce a low estrogenic state, affect only undegenerative leiomyoma tissue, the aim of the present study was to differentiate degenerative leiomyoma from undegenerative one by Gd-DTPA enhanced magnetic resonance imaging(MRI). There were 40 masses in 24 patients; all were diagnosed by surgical-pathology. With superconductive 0.5T MR circuit, T1-and T2-weighted images and Gd-DTPA T1-weighted images were obtained. Based on a combination of signal intensities of T2-weighted and enhanced T1 weighted image on the same tumor section all the lesions were classified to one of four MRI patterns. Pattern I was a heterogeneous hyperintensity on the T2-weighted images that was enhancement by Gd-DTPA. Pattern II was a high signal intensity on the T2-weighted MR images but no enhancement by Gd-DTPA. Pattern III was a low to intermediate signal intensity on the T2-weighted MR images and enhancement on the Gd-DTPA T1-weighted images. Pattern IV was a low to intermediate signal intensity on the T2-weighted images and no enhancement by Gd-DTPA. Each of these 4 groups of MRI pattern were co-related to the surgical-pathology findings. Pathologically, pattern I corresponded to an edematous leiomyoma in 3 cases and a connective tissue leiomyoma in one case. Pattern II corresponded to three red degeneration, two cystic degeneration and one infected leiomyoma. Pattern III corresponded to eighteen undegenerative leiomyomas, but some of them showed focal connective tissue proliferation. All of twelve cases in pattern IV corresponded to a hyaline degeneration. MRI with Gd-DTPA enhancement may differentiate undegenerative leiomyoma from degenerated one

  16. Degeneration of uterine leiomyoma: comparison between Gd-DTPA enhanced MR imaging and pathologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Shin, M. J.; Kim, G. W.; No, T. Y.; Ahn, W. H.; Baik, S. K.; Kim, B. G.; Choi, H. Y.; Paik, O. J. [Wallace Memorial Baptist Hospital, Busan (Korea, Republic of)

    1995-05-15

    Gonadotropin-releasing hormone(GnRH) analogues have been used as a conservative or preoperative therapy in the treatment of uterine leiomyoma. Since these drugs, which can induce a low estrogenic state, affect only undegenerative leiomyoma tissue, the aim of the present study was to differentiate degenerative leiomyoma from undegenerative one by Gd-DTPA enhanced magnetic resonance imaging(MRI). There were 40 masses in 24 patients; all were diagnosed by surgical-pathology. With superconductive 0.5T MR circuit, T1-and T2-weighted images and Gd-DTPA T1-weighted images were obtained. Based on a combination of signal intensities of T2-weighted and enhanced T1 weighted image on the same tumor section all the lesions were classified to one of four MRI patterns. Pattern I was a heterogeneous hyperintensity on the T2-weighted images that was enhancement by Gd-DTPA. Pattern II was a high signal intensity on the T2-weighted MR images but no enhancement by Gd-DTPA. Pattern III was a low to intermediate signal intensity on the T2-weighted MR images and enhancement on the Gd-DTPA T1-weighted images. Pattern IV was a low to intermediate signal intensity on the T2-weighted images and no enhancement by Gd-DTPA. Each of these 4 groups of MRI pattern were co-related to the surgical-pathology findings. Pathologically, pattern I corresponded to an edematous leiomyoma in 3 cases and a connective tissue leiomyoma in one case. Pattern II corresponded to three red degeneration, two cystic degeneration and one infected leiomyoma. Pattern III corresponded to eighteen undegenerative leiomyomas, but some of them showed focal connective tissue proliferation. All of twelve cases in pattern IV corresponded to a hyaline degeneration. MRI with Gd-DTPA enhancement may differentiate undegenerative leiomyoma from degenerated one.

  17. Magnetic resonance imaging of human cerebral infarction: Enhancement with Gd-DTPA

    Energy Technology Data Exchange (ETDEWEB)

    Imakita, S.; Nishimura, T.; Naito, H.; Yamada, N.; Yamamoto, K.; Takamiya, M.; Yamada, Y.; Sakashita, Y.; Minamikawa, J.; Kikuchi, H.

    1987-09-01

    Five patients (1 female and 4 males) with cerebral infarction of 4 h to 27 months duration were studied 9 times with magnetic resonance (MR) using Gd-DTPA. Spinecho (SE) MR images (MRI) were obtained before and after the administration of Gd-DTPA, and correlative CT scans were performed on the same day. In 2 cases, 4 h and 27 months after the ictus, there was no enhancement with Gd-DTPA. There was faint enhancement in 2 cases with cerebral infarction of about 24 h duration and obvious enhancement in all cases in the subacute stage. Compared with enhanced CT, MR using Gd-DTPA demonstrated more obvious enhancement of infarcted areas. MR enhancement using Gd-DTPA showed a gradual increase and the accumulated Gd-DTPA in infarcted areas slowly diffused to the periphery. MR enhancement with Gd-DTPA is similar to that of enhanced CT, but may be more sensitive in the detection of blood brain barrier breakdown.

  18. Enhanced MRI in patients with facial palsy

    International Nuclear Information System (INIS)

    Yanagida, Masahiro; Kato, Tsutomu; Ushiro, Koichi; Kitajiri, Masanori; Yamashita, Toshio; Kumazawa, Tadami; Tanaka, Yoshimasa

    1991-01-01

    We performed Gd-DTPA-enhanced magnetic resonance imaging (MRI) examinations at several stages in 40 patients with peripheral facial nerve palsy (Bell's palsy and Ramsay-Hunt syndrome). In 38 of the 40 patients, one and more enhanced region could be seen in certain portion of the facial nerve in the temporal bone on the affected side, whereas no enhanced regions were seen on the intact side. Correlations between the timing of the MRI examination and the location of the enhanced regions were analysed. In all 6 patients examined by MRI within 5 days after the onset of facial nerve palsy, enhanced regions were present in the meatal portion. In 3 of the 8 patients (38%) examined by MRI 6 to 10 days after the onset of facial palsy, enhanced areas were seen in both the meatal and labyrinthine portions. In 8 of the 9 patients (89%) tested 11 to 20 days after the onset of palsy, the vertical portion was enhanced. In the 12 patients examined by MRI 21 to 40 days after the onset of facial nerve palsy, the meatal portion was not enhanced while the labyrinthine portion, the horizontal portion and the vertical portion were enhanced in 5 (42%), 8 (67%) and 11 (92%), respectively. Enhancement in the vertical portion was observed in all 5 patients examined more than 41 days after the onset of facial palsy. These results suggest that the central portion of the facial nerve in the temporal bone tends to be enhanced in the early stage of facial nerve palsy, while the peripheral portion is enhanced in the late stage. These changes of Gd-DTPA enhanced regions in the facial nerve may suggest dromic degeneration of the facial nerve in peripheral facial nerve palsy. (author)

  19. Gadolinium-DTPA enhanced MRI in myocardial infarction

    International Nuclear Information System (INIS)

    Dijkman, P.R.M. van.

    1991-01-01

    This thesis focuses on one aspect of cardiac magnetic resonance imaging (MRI) for noninvasive screening of ischemic heart disease: the identification and quantification of acutely infarcted myocardium using gadolineum-diethylene triamine pentaacetic acid (Gd-DTPA) enhanced T1-weighted MRI in a clinical and experimental setting. (author). 296 refs.; 34 figs.; 4 tabs

  20. Synthesis and evaluation of novel polysaccharide-Gd-DTPA compounds as contrast agent for MRI

    Science.gov (United States)

    Sun, Guoying; Feng, Jianghua; Jing, Fengying; Pei, Fengkui; Liu, Maili

    2003-09-01

    Macromolecular conjugates of two kinds of natural polysaccharides, that from Panax quinquefolium linn (PQPS) and Ganoderma applanatum pat (GAPS), with gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA) have been synthesized and characterized by means of FTIR, elementary analysis and ICP-AES. Their stability was investigated by competition study with Ca 2+, EDTA (ethylenediaminetetraacetic acid) and DTPA. Polysaccharide-bound complexes exhibit T1 relaxivities of 1.5-1.7 times that of Gd-DTPA in D 2O at 25°C and 9.4 T. MR imaging of Sprague-Dawley (SD) rats showed remarkable enhancement in rat liver and kidney after i.v. injection of these two complexes: liver parenchyma 60.9±5.6%, 57.8±7.4% at 65-85 min; kidney 144.9±14.5%, 199.9±25.4% at 10-30 min for PQPS-Gd-DTPA, GAPS-Gd-DTPA at gadolinium dose of 0.083 and 0.082 mmol/kg, respectively. Our preliminary in vivo and in vitro study indicates that the two kinds of polysaccharide-bound complexes are potential tissue-specific contrast agents for MRI.

  1. Gd-DTPA enhanced MR imaging in Bell's palsy

    International Nuclear Information System (INIS)

    Matsumoto, Yasushi; Kawamura, Yuji; Yanagihara, Naoaki; Sadamoto, Masanori; Sadamoto, Kazuhiko.

    1991-01-01

    Magnetic resonance imaging (MRI) was carried out in 27 patients with Bell's palsy. T1-weighted spin-echo images (TR500/TE25-34) were taken before and after the intravenous administration of Gd-DTPA (0.1 mmol/kg) with 0.5T superconductive MRI. There was significant enhancement at the geniculate ganglion and the horizontal segment of the involved facial nerve in 22 patients (81.5%) and at the vertical segment in 20 (74.1%). Enhancement at the meatal fundus was seen in only 4 patients (14.9%) and at the labyrinthine segment in 8 (29.6%). These results corroborate other evidence that the geniculate ganglion is involved most frequently in Bell's palsy. In addition, the enhancement of the proximal portion, i.e. the meatal fundus and the labyrinthine segment of the nerve, although not common, noted in this study may be important in the diagnosis and treatment of Bell's palsy. (author)

  2. Percent wall thickness evaluated by Gd-DTPA enhanced cine MRI as an indicator of local parietal movement in hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    Hirano, Masaharu

    1998-01-01

    Hypertrophic cardiomyopathy (HCM) is a cardiac disease, the basic pathology of which consists of a decrease in left ventricular dilation compliance due to uneven hypertrophy of the left ventricular wall. Magnetic resonance imaging (MRI) is useful in monitoring uneven parietal hypertrophy and kinetics in HCM patients. The present study was undertaken in 47 HCM patients who showed asymmetrical septal hypertrophy to determine if percent thickness can be an indicator of left ventricular local movement using cine MRI. Longest and shortest axis images were acquired by the ECG synchronization method using a 1.5 T MR imager. Cardiac function was analyzed based on longest axis cine images, and telediastolic and telesystolic parietal thickness were measured based on shorter axis cine images at the papillary muscle level. Parietal movement index and percent thickness were used as indicators of local parietal movement. The correlation between these indicators and parietal thickness was evaluated. The percent thickness changed at an earlier stage of hypertrophy than the parietal movement index, thus it is thought to be useful in detecting left ventricular parietal movement disorders at an early stage of HCM. (author)

  3. Percent wall thickness evaluated by Gd-DTPA enhanced cine MRI as an indicator of local parietal movement in hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Masaharu [Tokyo Medical Coll. (Japan)

    1998-11-01

    Hypertrophic cardiomyopathy (HCM) is a cardiac disease, the basic pathology of which consists of a decrease in left ventricular dilation compliance due to uneven hypertrophy of the left ventricular wall. Magnetic resonance imaging (MRI) is useful in monitoring uneven parietal hypertrophy and kinetics in HCM patients. The present study was undertaken in 47 HCM patients who showed asymmetrical septal hypertrophy to determine if percent thickness can be an indicator of left ventricular local movement using cine MRI. Longest and shortest axis images were acquired by the ECG synchronization method using a 1.5 T MR imager. Cardiac function was analyzed based on longest axis cine images, and telediastolic and telesystolic parietal thickness were measured based on shorter axis cine images at the papillary muscle level. Parietal movement index and percent thickness were used as indicators of local parietal movement. The correlation between these indicators and parietal thickness was evaluated. The percent thickness changed at an earlier stage of hypertrophy than the parietal movement index, thus it is thought to be useful in detecting left ventricular parietal movement disorders at an early stage of HCM. (author)

  4. Brain metastasis of small cell lung carcinoma. Comparison of Gd-DTPA enhanced magnetic resonance imaging and enhanced computerized tomography

    International Nuclear Information System (INIS)

    Nomoto, Yasushi; Yamaguchi, Yutaka; Miyamoto, Tadaaki.

    1994-01-01

    Small cell carcinoma of the lung (SCLC) frequently metastasizes into the brain, resulting in serious influences upon prognosis. Delayed brain damage caused by prophylactic cranial irradiation (PCI) is also problematic. Gadolinium diethylene triamine pentaacetic acid (Gd-DTPA) enhanced magnetic resonance imaging (MRI) was performed to detect early brain metastasis from SCLC, and its usefulness was compared with contrast computerized tomography (CT). Among 25 SCLC patients, brain metastasis was detected in 11 by MRI and in 10 by CT, although six of them were completely asymptomatic. In the 11 patients, 6.3 and 2.4 lesions were respectively detected on average by MRI and CT. The ability of MRI to detect metastatic lesions of ≥15 mm diameter did not differ from that of CT, but became different as lesions became smaller (P<0.002), and MRI had a decided advantage over CT because as many as 30 lesions of ≤5 mm diameter were detected by MRI, whereas such lesions visualized on CT numbered only one (P<0.0001). MRI was incomparably superior to CT (P<0.0004) for subtentorial lesions since 18 lesions were detected on MRI, but only three, measuring ≥25 mm in diameter, were demonstrated on CT. Gd-DTPA enhanced MRI was determined to be extremely useful in the early diagnosis of SCLC brain metastasis. MRI was thought to reduce delayed brain damage caused by PCI if performed according to an adequate schedule. (author)

  5. Demonstration of evolution of hemispherical spondysclerosis by contrast enhanced Gd-DTPA magnetic resonance imaging

    International Nuclear Information System (INIS)

    Jevtic, V.; Majcen, N.

    2004-01-01

    Background. The purpose of the study was to estimate the value of Gd-DTPA magnetic resonance imaging (MRI) in demonstrating the evolution of hemispherical spondylosclerosis (HSS). Patients and methods. In eighteen patients with chronic low back pain and typical radiographic findings of HSS seen on plain films, Gd-DTPA MRI of the lumbar spine was performed. MRI morphological and signal intensity appearances of HSS were analysed and compared with radiographic changes. Results. On the basis of MRI features, three distinct groups of cases were identifiable. Within the first group the region of dome-shaped osteosclerosis demonstrated low signal intensity on T1-weighted precontrast spin-echo images, high signal intensity on T2-weighted images and diffuse contrast enhancement on T1-weighted postcontrast images, findings compatible with bone marrow oedema and hyperaemia. The second group showed high signal intensity vertebral body corners surrounded by low signal intensity area, which indicated the combination of fat accumulation and the sclerotic bone. In the third intermediate group anterior disco-vertebral junctions revealed a mixture of MRI appearances characteristic of the first and the second group. Conclusions. Gd-DTPA MRI is capable of demonstrating a spectrum of features which reflect the evolution of HSS. These typical appearances showed by MRI could be of eventual clinical relevance in following the progression of HSS. (author)

  6. T1-T2 dual-modal MRI of brain gliomas using PEGylated Gd-doped iron oxide nanoparticles.

    Science.gov (United States)

    Xiao, Ning; Gu, Wei; Wang, Hao; Deng, Yunlong; Shi, Xin; Ye, Ling

    2014-03-01

    To overcome the negative contrast limitations of iron oxide-based contrast agents and to improve the biocompatibility of Gd-chelate contrast agents, PEGylated Gd-doped iron oxide (PEG-GdIO) NPs as a T1-T2 dual-modal contrast agent were synthesized by the polyol method. The transverse relaxivity (r2) and longitudinal relaxivity (r1) of PEG-GdIO were determined to be 66.9 and 65.9 mM(-1) s(-1), respectively. The high r1 value and low r2/r1 ratio make PEG-GdIO NPs suitable as a T1-T2 dual-modal contrast agent. The in vivo MRI demonstrated a brighter contrast enhancement in T1-weighted image and a simultaneous darken effect in T2-weighted MR image compared to the pre-contrast image in the region of glioma. Furthermore, the biocompatibility of PEG-GdIO NPs was confirmed by the in vitro MTT cytotoxicity and in vivo histological analyses (H&E). Therefore, PEG-GdIO NPs hold great potential in T1-T2 dual-modal imaging for the diagnosis of brain glioma. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Gd(iii)-doped carbon dots as a dual fluorescent-MRI probe

    KAUST Repository

    Bourlinos, Athanasios B.; Bakandritsos, Aristides; Kouloumpis, Antonios; Gournis, Dimitrios; Krysmann, Marta; Giannelis, Emmanuel P.; Polakova, Katerina; Safarova, Klara; Hola, Katerina; Zboril, Radek

    2012-01-01

    We describe the synthesis of Gd(iii)-doped carbon dots as dual fluorescence-MRI probes for biomedical applications. The derived Gd(iii)-doped carbon dots show uniform particle size (3-4 nm) and gadolinium distribution and form stable dispersions in water. More importantly, they exhibit bright fluorescence, strong T1-weighted MRI contrast and low cytotoxicity. © The Royal Society of Chemistry 2012.

  8. Off-site evaluation of liver lesion detection by Gd-BOPTA-enhanced MR imaging

    International Nuclear Information System (INIS)

    Gehl, H.B.; Bourne, M.; Grazioli, L.; Moeller, A.; Lodemann, K.P.

    2001-01-01

    The aim of this study was to determine the efficacy of Gd-BOPTA-enhanced MRI in liver lesion detection in comparison with unenhanced MRI and dynamic CT. The image sets of 148 of 151 patients enrolled in a multicenter German phase-III trial were evaluated by two independent radiologists unaffiliated with the investigating centers. Patients underwent a routine MRI protocol comprising T2- and T1-weighted spin-echo and T1-weighted gradient-echo (GE) sequences pre and 1 h post 0.1 mmol/kg Gd-BOPTA (Bracco-Byk Gulden, Konstanz, Germany). Additionally, a serial T1-weighted GE scan was performed after administration of the first half of the dose. All patients underwent dynamic contrast-enhanced CT. The evaluation was performed with regard to the number and size of lesions detected per patient by each modality or sequence. Furthermore, all pre CM and pre + post CM image sets were analyzed for number of lesions per patient. Both readers detected significantly more lesions in the contrast-enhanced image set compared with the unenhanced image set (32 and 39 %, respectively; p < 0.0001). While contrast-enhanced CT detected a similar number of lesions to unenhanced MRI, it was clearly inferior to contrast-enhanced MRI (reader 1: p = 0.0117; reader 2: p = 0.0225). Of the T1-weighted scans performed, the dynamic and late T1-weighted GE exams contributed most to the increased lesion detection rate (reader 1: p = 0.0007; reader 2: p = 0.0037). The size of the smallest lesion detected by means of MRI was significantly larger in the pre-CM image sets than in the pre + post CM image sets (reader 1: p = 0.001; reader 2: p < 0.0001). Gd-BOPTA-enhanced MRI detected significantly smaller lesions than contrast-enhanced CT (reader 1: p = 0.0117; reader 2: p = 0.0925). Gd-BOPTA-enhanced MR imaging improves liver lesion detection significantly over unenhanced MRI and dynamic CT. (orig.)

  9. Off-site evaluation of liver lesion detection by Gd-BOPTA-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gehl, H.B. [Inst. of Diagnostic Radiology, Medical Univ. of Luebeck (Germany); Bourne, M. [Dept. of Radiology, Univ. Hospital of Wales, Cardiff (United Kingdom); Grazioli, L. [Dept. of Radiology, Univ. of Brescia (Italy); Moeller, A. [MEDIDATA GmbH, Konstanz (Germany); Lodemann, K.P. [BRACCO-BYK GULDEN GmbH, Konstanz (Germany)

    2001-02-01

    The aim of this study was to determine the efficacy of Gd-BOPTA-enhanced MRI in liver lesion detection in comparison with unenhanced MRI and dynamic CT. The image sets of 148 of 151 patients enrolled in a multicenter German phase-III trial were evaluated by two independent radiologists unaffiliated with the investigating centers. Patients underwent a routine MRI protocol comprising T2- and T1-weighted spin-echo and T1-weighted gradient-echo (GE) sequences pre and 1 h post 0.1 mmol/kg Gd-BOPTA (Bracco-Byk Gulden, Konstanz, Germany). Additionally, a serial T1-weighted GE scan was performed after administration of the first half of the dose. All patients underwent dynamic contrast-enhanced CT. The evaluation was performed with regard to the number and size of lesions detected per patient by each modality or sequence. Furthermore, all pre CM and pre + post CM image sets were analyzed for number of lesions per patient. Both readers detected significantly more lesions in the contrast-enhanced image set compared with the unenhanced image set (32 and 39 %, respectively; p < 0.0001). While contrast-enhanced CT detected a similar number of lesions to unenhanced MRI, it was clearly inferior to contrast-enhanced MRI (reader 1: p = 0.0117; reader 2: p = 0.0225). Of the T1-weighted scans performed, the dynamic and late T1-weighted GE exams contributed most to the increased lesion detection rate (reader 1: p = 0.0007; reader 2: p = 0.0037). The size of the smallest lesion detected by means of MRI was significantly larger in the pre-CM image sets than in the pre + post CM image sets (reader 1: p = 0.001; reader 2: p < 0.0001). Gd-BOPTA-enhanced MRI detected significantly smaller lesions than contrast-enhanced CT (reader 1: p = 0.0117; reader 2: p = 0.0925). Gd-BOPTA-enhanced MR imaging improves liver lesion detection significantly over unenhanced MRI and dynamic CT. (orig.)

  10. Pharmacokinetics of Chiral Dendrimer-Triamine-Coordinated Gd-MRI Contrast Agents Evaluated by in Vivo MRI and Estimated by in Vitro QCM

    Directory of Open Access Journals (Sweden)

    Yuka Miyake

    2015-12-01

    Full Text Available Recently, we developed novel chiral dendrimer-triamine-coordinated Gd-MRI contrast agents (Gd-MRI CAs, which showed longitudinal relaxivity (r1 values about four times higher than that of clinically used Gd-DTPA (Magnevist®, Bayer. In our continuing study of pharmacokinetic differences derived from both the chirality and generation of Gd-MRI CAs, we found that the ability of chiral dendrimer Gd-MRI CAs to circulate within the body can be directly evaluated by in vitro MRI (7 T. In this study, the association constants (Ka of chiral dendrimer Gd-MRI CAs to bovine serum albumin (BSA, measured and calculated with a quartz crystal microbalance (QCM in vitro, were found to be an extremely easy means for evaluating the body-circulation ability of chiral dendrimer Gd-MRI CAs. The Ka values of S-isomeric dendrimer Gd-MRI CAs were generally greater than those of R-isomeric dendrimer Gd-MRI CAs, which is consistent with the results of our previous MRI study in vivo.

  11. Fate of hypointense lesions on Gd-EOB-DTPA-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Akai, Hiroyuki; Matsuda, Izuru; Kiryu, Shigeru; Tajima, Taku; Takao, Hidemasa; Watanabe, Yasushi; Imamura, Hiroshi; Kokudo, Norihiro

    2012-01-01

    Purpose: To investigate the natural outcome and clinical implication of hypointense lesions in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI. Materials and methods: Forty patients underwent Gd-EOB-DTPA-enhanced MRI for preoperative evaluation of HCC. Hypointense lesions in the hepatobiliary phase that were hypovascular 5 mm of more were extracted for follow-up. We performed a longitudinal study retrospectively for these lesions regardless of whether classical HCC developed or emerged in a different area from that of the lesions being followed. Results: Thirty one patients displayed 130 hypointense lesions on MRI and only nine showed no hypointense lesions. In total, 17 (13.1%) of 130 hypointense lesions on MRI developed into classical HCC. The cumulative rates for these lesions to develop into classical HCC were 3.2% at 1 year, 11.1% at 2 years and 15.9% at 3 years. The total occurrence rates of classical HCC (25.8% at 1 year, 52.6% at 2 years and 76.4% at 3 years) were higher compared to those regarding only occurrence of classical HCC from hypointense lesions on MRI (10.0% at 1 year, 35.6% at 2 years and 44.6% at 3 years), although no significant difference was observed (p = 0.073). Conclusions: Hypointense lesions that are detected in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI have some malignant potential, although treating these lesions aggressively in patients who already have HCC may be too severe.

  12. The enhancement effects of Gd-DTPA for cerebro-spinal lesions

    International Nuclear Information System (INIS)

    Mano, Isamu; Yoshida, Hideo; Kono, Takeshi; Tsuchida, Takashi; Terao, Hideo; Iio, Masahiro.

    1987-01-01

    Effects of Gadolinium DTPA enhancement in MRI for cerebro-spinal lesions were studied on 20 patients. In this study, pre-contrast T 2 weighted image and the postcontrast T 1 weighted image were, especially, compared. Out of 20 cases investigated, the clinical significance of Gd-DTPA was recognized clearly in 14 cases. In the other 6 cases, some new information, though which did not give us the direct clinical significance, was also obtained. It was confirmed that T 2 weighted sequence without Gd-DTPA was the best in sensitivity, while T 1 weighted sequence after Gd-DTPA administration was superior in specificity of the information in making a discrimination between tumor and edema, gliosis and in the time-course of infarction. (author)

  13. Gd-EOB-DTPA-enhanced magnetic resonance images of hepatocellular carcinoma: correlation with histological grading and portal blood flow

    Energy Technology Data Exchange (ETDEWEB)

    Kogita, Sachiyo; Imai, Yasuharu; Fukuda, Kazuto; Igura, Takumi; Sawai, Yoshiyuki [Ikeda Municipal Hospital, Department of Gastroenterology, Osaka (Japan); Okada, Masahiro; Murakami, Takamichi [Kinki University, School of Medicine, Department of Radiology, Osaka (Japan); Kim, Tonsok; Onishi, Hiromitsu; Hori, Masatoshi [Osaka University, Graduate School of Medicine, Department of Radiology, Osaka (Japan); Takamura, Manabu [Ikeda Municipal Hospital, Department of Radiology, Osaka (Japan); Morimoto, Osakuni [Ikeda Municipal Hospital, Department of Surgery, Osaka (Japan); Nagano, Hiroaki [Osaka University, Graduate School of Medicine, Department of Surgery, Osaka (Japan); Wakasa, Kenichi [Osaka City University, Graduate School of Medicine, Department of Diagnostic Pathology, Osaka (Japan); Hayashi, Norio [Osaka University, Graduate School of Medicine, Department of Gastroenterology and Hepatology, Osaka (Japan)

    2010-10-15

    To retrospectively investigate enhancement patterns of hepatocellular carcinoma (HCC) and dysplastic nodule (DN) in the hepatobiliary phase of gadolinium-ethoxybenzyl-diethylenetriamine (Gd-EOB-DTPA)-enhanced MRI in relation to histological grading and portal blood flow. Sixty-nine consecutive patients with 83 histologically proven HCCs and DNs were studied. To assess Gd-EOB-DTPA uptake, we calculated the EOB enhancement ratio, which is the ratio of the relative intensity of tumorous lesion to surrounding nontumorous area on hepatobiliary phase images (post-contrast EOB ratio) to that on unenhanced images (pre-contrast EOB ratio). Portal blood flow was evaluated by CT during arterial portography. Post-contrast EOB ratios significantly decreased as the degree of differentiation declined in DNs (1.00 {+-} 0.14) and well, moderately and poorly differentiated HCCs (0.79 {+-} 0.19, 0.60 {+-} 0.27, 0.49 {+-} 0.10 respectively). Gd-EOB-DTPA uptake, assessed by EOB enhancement ratios, deceased slightly in DNs and still more in HCCs, while there was no statistical difference in the decrease between different histological grades of HCC. Reductions in portal blood flow were observed less frequently than decreases in Gd-EOB-DTPA uptake in DNs and well-differentiated HCCs. Reduced Gd-EOB-DTPA uptake might be an early event of hepatocarcinogenesis, preceding portal blood flow reduction. The hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI may help estimate histological grading, although difficulties exist in differentiating HCCs from DNs. (orig.)

  14. Effects of endocrine therapy on the primary lesion in patients with prostatic cancer. Evaluation with Gd-dynamic subtraction MRI

    International Nuclear Information System (INIS)

    Yoshizako, Takeshi; Watanabe, Yuji; Dohke, Masako

    2000-01-01

    The effects of endocrine therapy on prostate cancer were assessed by using Gd-dynamic subtraction MRI (DSMRI). The 36 lesions showed early enhancement before therapy were treated with endocrine therapy. The criteria used for the assessment of therapeutic effect was; the degree of early enhancement could decrease with the viability of cancer reduced by treatment. According to this criteria, the sensitivity, specificity, and accuracy were 35.7% (5/14), 81.8% (18/22), and 58.3% (21/36). In conclusion, interval decrease of early enhancement could be a indicator of therapeutic effect. (author)

  15. Theranostic Gd(III)-lipid microbubbles for MRI-guided focused ultrasound surgery.

    Science.gov (United States)

    Feshitan, Jameel A; Vlachos, Fotis; Sirsi, Shashank R; Konofagou, Elisa E; Borden, Mark A

    2012-01-01

    We have synthesized a biomaterial consisting of Gd(III) ions chelated to lipid-coated, size-selected microbubbles for utility in both magnetic resonance and ultrasound imaging. The macrocyclic ligand DOTA-NHS was bound to PE headgroups on the lipid shell of pre-synthesized microbubbles. Gd(III) was then chelated to DOTA on the microbubble shell. The reaction temperature was optimized to increase the rate of Gd(III) chelation while maintaining microbubble stability. ICP-OES analysis of the microbubbles determined a surface density of 7.5 × 10(5) ± 3.0 × 10(5) Gd(III)/μm(2) after chelation at 50 °C. The Gd(III)-bound microbubbles were found to be echogenic in vivo during high-frequency ultrasound imaging of the mouse kidney. The Gd(III)-bound microbubbles also were characterized by magnetic resonance imaging (MRI) at 9.4 T by a spin-echo technique and, surprisingly, both the longitudinal and transverse proton relaxation rates were found to be roughly equal to that of no-Gd(III) control microbubbles and saline. However, the relaxation rates increased significantly, and in a dose-dependent manner, after sonication was used to fragment the Gd(III)-bound microbubbles into non-gas-containing lipid bilayer remnants. The longitudinal (r(1)) and transverse (r(2)) molar relaxivities were 4.0 ± 0.4 and 120 ± 18 mM(-1)s(-1), respectively, based on Gd(III) content. The Gd(III)-bound microbubbles may find application in the measurement of cavitation events during MRI-guided focused ultrasound therapy and to track the biodistribution of shell remnants. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. MRI sensing of neurotransmitters with a crown ether appended Gd(3+) complex.

    Science.gov (United States)

    Oukhatar, Fatima; Même, Sandra; Même, William; Szeremeta, Frédéric; Logothetis, Nikos K; Angelovski, Goran; Tóth, Éva

    2015-02-18

    Molecular magnetic resonance imaging (MRI) approaches that detect biomarkers associated with neural activity would allow more direct observation of brain function than current functional MRI based on blood-oxygen-level-dependent contrast. Our objective was to create a synthetic molecular platform with appropriate recognition moieties for zwitterionic neurotransmitters that generate an MR signal change upon neurotransmitter binding. The gadolinium complex (GdL) we report offers ditopic binding for zwitterionic amino acid neurotransmitters, via interactions (i) between the positively charged and coordinatively unsaturated metal center and the carboxylate function and (ii) between a triazacrown ether and the amine group of the neurotransmitters. GdL discriminates zwitterionic neurotransmitters from monoamines. Neurotransmitter binding leads to a remarkable relaxivity change, related to a decrease in hydration number. GdL was successfully used to monitor neural activity in ex vivo mouse brain slices by MRI.

  17. Flip angle modulations in late phase Gd-EOB-DTPA MRI improve the identification of the biliary system

    Energy Technology Data Exchange (ETDEWEB)

    Stelter, Lars, E-mail: lars.stelter@charite.de [Klinik fuer Radiologie, Charite - Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Grieser, Christian, E-mail: christian.grieser@charite.de [Klinik fuer Radiologie, Charite - Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Fernandes, Carmen Maria Perez, E-mail: carmen.perez-fernandez@charite.de [Klinik fuer Radiologie, Charite - Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Rothe, Jan Holger, E-mail: jan-holger.rothe@charite.de [Klinik fuer Radiologie, Charite - Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Streitparth, Florian, E-mail: florian.streitparth@charite.de [Klinik fuer Radiologie, Charite - Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Seehofer, Daniel, E-mail: daniel.seehofer@charite.de [Klinik fuer Allgemein-, Viszeral- und Transplantationschirurgie, Charite - Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); and others

    2012-11-15

    Objectives: To assess the improvement of bile duct visualization in Gd-EOB-DTPA enhanced MR-cholangiography (EOB-MRC) by using an increased flip angle. Methods: 35 patients underwent Gd-EOB-DTPA enhanced MRI of the liver including T2-weighted MRCP and hepatobiliary phase EOB-MRC using a flip angle of 10 Degree-Sign (FA10) and of 35 Degree-Sign (FA35), respectively. Images were evaluated regarding the delineation of biliary ducts, the order of branching and anatomic visualization of the biliary tree. ROI analysis was performed to estimate the signal-to-noise (SNR) and contrast-to-noise (CNR) ratios. Results: Applying the FA35 resulted in a significantly better SNR and CNR as compared to FA10. The overall image quality was rated as good for both, FA10 and FA35. The overall rating for regional delineation of the biliary system was rated significantly better for FA35 than for FA10 (p = 0.02). Classification of bile duct anatomy variations, however, was equivalent in both techniques. Conclusions: Increasing the flip angle of a T1-weighted 3D-sequence from 10 Degree-Sign to 35 Degree-Sign during the hepatobiliary phase of Gd-EOB enhanced MRI visually and quantitatively improved the visualization of the biliary ducts.

  18. MRI of the liver with the new contrast medium Gd-BOPTA

    International Nuclear Information System (INIS)

    Vogl, T.J.; Pegios, W.; Balzer, J.; Lissner, J.; Pirovano, G.

    1992-01-01

    A phase 1 study on 8 normals has been carried out to determine the effectiveness and safety during MRI of a new hepatobiliary contrast medium Gd-BOPTA for causing enhancement of the upper abdominal organs. Gradient echo sequences (flash), T 1 and T 2 -weighted spin echo sequences and turbo-flash sequences were used. The contrast medium was given as a single infusion in various concentrations (0.005, 0.05, 0.1 and 0.2 mmol/kg body weight). Optimal contrast of liver parenchyma was obtained with a dose of 0.05-0.1 mmol/kg body weight, resulting in contrast increase of 149.1% during gradient echo sequences and 107.8% during T 1 spin echo sequences. In general, the increased contrast lasted for about two hours. Because of the biliary and renal excretion there was an enormous increase in signal intensity of the bile ducts and a significant increase in the kidneys and ureters. The results of the first in-vivo-trial of Gd-BOPTA encourages the performance of further clinical studies of this new hepatobiliary contrast medium. (orig.) [de

  19. Gd (III) chelates adsorbed on TiO2 nanoparticles - promising MRI contrast agent

    International Nuclear Information System (INIS)

    Rehor, Ivan; Lukes, Ivan; Peters, Joop A.; Jirak, Daniel

    2009-01-01

    Full text: The project deals with a new contrast agent (CA) for magnetic resonance imaging (MRI). The CA consists of two main parts - diamagnetic core (TiO 2 nanoparticle) and Gd (III) chelates grafted on its surface. The presence of the nanoparticle core is responsible for significant increase of r1 millimolar relaxivity (which corresponds to the efficiency of the CA) due to the slowing down the rotation of the complex in solution. It also affects the biodistribution characteristics of the CA - the ability to penetrate through cell membranes is well known for nanoparticles, making them useful for cell labeling. The structure of the chelate is derived from DOTA ligand, whose Gd (III) complexes are commercially used as MRI CA in human medicine. The connection of the complex to the surface is realized via penylphosphonate, which is attached to the pendant arm of the ligand. Strong interaction of the phosphonate with the TiO 2 surface results in the full surface coverage. The complexation and MRI properties of Gd chelate were studied and exhibit analogy to the complexes of DOTA, The millimolar relaxivity (r1) of the Gd (III) complex significantly increases upon adsorption on the TiO 2 nanoparticles. PVA was added to the colloidal solutions of CA to stabilize them under biological conditions and such stabilized CA was utilized for MRI visualization of rat pancreatic islets (P1). The labeled islets were detected on MR images as hyperintense area and therefore our CA seems to be promising material for cellular MRI

  20. Gadolinium-enhanced MRI for evaluation of peripheral nerve neuropathy

    International Nuclear Information System (INIS)

    Hayakawa, Katsuhiko; Kobayashi, Shigeru; Suzuki, Katsuji; Yamada, Mitsuko; Kojima, Motohiro.

    1995-01-01

    We carried out enhanced MRI for the carpal tunnel syndrome, cubital tunnel syndrome, tarsal tunnel syndrome and anterior interosseous nerve palsy that is entrapment neuropathy. The affected nerve was enhanced in entrapment point. Carpal tunnel syndrome: The enhancement of affected nerve was apparent in 41 of 52 cases (79%). Cubital tunnel syndrome: The enhancement of affected nerve was apparent in 4 of 5 cases (80%). Tarsal tunnel syndrome: The enhancement of affected nerve was apparent in 1 of 1 case. Anterior interosseous nerve palsy: The enhancement of affected nerve was apparent in 3 of 4 cases (75%). The affected nerve was strongly enhanced by Gd-DTPA, indicating the blood-nerve barrier in the affected nerve to be broken and intraneural edema to be produced, e.i., the ability of Gd-DTPA to selectively contrast-enhance a pathologic focus within the peripheral nerve is perhaps its most important clinical applications. (author)

  1. Gadolinium-enhanced MRI for evaluation of peripheral nerve neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Katsuhiko [Aikoh Orthopaedic Hospital, Nagoya (Japan); Kobayashi, Shigeru; Suzuki, Katsuji; Yamada, Mitsuko; Kojima, Motohiro

    1995-11-01

    We carried out enhanced MRI for the carpal tunnel syndrome, cubital tunnel syndrome, tarsal tunnel syndrome and anterior interosseous nerve palsy that is entrapment neuropathy. The affected nerve was enhanced in entrapment point. Carpal tunnel syndrome: The enhancement of affected nerve was apparent in 41 of 52 cases (79%). Cubital tunnel syndrome: The enhancement of affected nerve was apparent in 4 of 5 cases (80%). Tarsal tunnel syndrome: The enhancement of affected nerve was apparent in 1 of 1 case. Anterior interosseous nerve palsy: The enhancement of affected nerve was apparent in 3 of 4 cases (75%). The affected nerve was strongly enhanced by Gd-DTPA, indicating the blood-nerve barrier in the affected nerve to be broken and intraneural edema to be produced, e.i., the ability of Gd-DTPA to selectively contrast-enhance a pathologic focus within the peripheral nerve is perhaps its most important clinical applications. (author).

  2. A neutral polydisulfide containing Gd(III) DOTA monoamide as a redox-sensitive biodegradable macromolecular MRI contrast agent.

    Science.gov (United States)

    Ye, Zhen; Zhou, Zhuxian; Ayat, Nadia; Wu, Xueming; Jin, Erlei; Shi, Xiaoyue; Lu, Zheng-Rong

    2016-01-01

    This work aims to develop safe and effective gadolinium (III)-based biodegradable macromolecular MRI contrast agents for blood pool and cancer imaging. A neutral polydisulfide containing macrocyclic Gd-DOTA monoamide (GOLS) was synthesized and characterized. In addition to studying the in vitro degradation of GOLS, its kinetic stability was also investigated in an in vivo model. The efficacy of GOLS for contrast-enhanced MRI was examined with female BALB/c mice bearing 4T1 breast cancer xenografts. The pharmacokinetics, biodistribution, and metabolism of GOLS were also determined in mice. GOLS has an apparent molecular weight of 23.0 kDa with T1 relaxivities of 7.20 mM(-1) s(-1) per Gd at 1.5 T, and 6.62 mM(-1) s(-1) at 7.0 T. GOLS had high kinetic inertness against transmetallation with Zn(2+) ions, and its polymer backbone was readily cleaved by L-cysteine. The agent showed improved efficacy for blood pool and tumor MR imaging. The structural effect on biodistribution and in vivo chelation stability was assessed by comparing GOLS with Gd(HP-DO3A), a negatively charged polydisulfide containing Gd-DOTA monoamide GODC, and a polydisulfide containing Gd-DTPA-bisamide (GDCC). GOLS showed high in vivo chelation stability and minimal tissue deposition of gadolinium. The biodegradable macromolecular contrast agent GOLS is a promising polymeric contrast agent for clinical MR cardiovascular imaging and cancer imaging. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Gd-DTPA MR imaging enhancement of spinal cord tumors

    International Nuclear Information System (INIS)

    Dillon, W.P.; Bolla, K.; Mark, A.S.; Tsudura, J.S.; Norman, D.; Newton, T.H.

    1987-01-01

    Nineteen patients with suspected spinal cord tumors were imaged with T1- and T2-weighted sequences before and after the administration of Gd-DTPA (0.1 mmol/kg). Eleven of the 19 patients had spinal cord tumors (three unproven). Eight of 11 patients had intramedullary tumors (four astrocytomas, two ependymomas) and two had extra-medullary tumors (one meningioma, one metastatic melanoma). Other lesions studied include idiopathic syringomyelia (two), spinal arteriovenous malformation (AVM) (one), posttraumatic arachnoiditis (one), and cord infarct (one). All of the tumors enhanced after the administration of Gd-DTPA. Spinal cord enhancement was also noted in association with a spinal cord AVM, a suspected cord infarct, and in the patient with severe arachnoiditis. No enhancement was present in patients with idiopathic or posttraumatic syringomyelia or in the three normal patients. In six of the patients, enhancement was critical in confirming disease that was questionable on the precontrast MR images. Gadolinium enhancement allowed differentiation of tumor from postoperative changes in two patients with spinal cord tumors. Enhanced images localized the lesion more accurately than precontrast MR images in eight patients. In four patients a lesion could only be detected after the administration of contrast. The postcontrast images better defined the margin of tumor from surrounding edema, operative scarring, and cord cavitation. The AVM case had enhancement of slowly flowing veins with Gd-DTPA posterior to an ischemic cord segment. Gd-DTPA enhancement is extremely useful in the detection and therapeutic assessment of spinal cord tumors; however, enhancement is not specific for tumors and should be interpreted in light of the clinical setting

  4. Gd-DTPA-enhanced MR imaging in meningitis

    International Nuclear Information System (INIS)

    Han, M.H.; Chang, K.H.; Roh, J.K.; Kim, I.O.; Han, M.C.; Kim, C.W.

    1988-01-01

    Gd-DPTA-enhanced MR imaging was performed in 16 patients with meningitis (seven tuberculous, four bacterial, three fungal, and two viral) on a 2.0-T unit. Hemorrhagic infarcts of basal ganglia and localized enhancement of thickened dura adjacent were demonstrated on T1-weighted images in three patients with tuberculous meningitis and four with bacterial meningitis, respectively, that were not seen on CT. Enhanced T1-weighted images readily differentiated leptomeningeal enhancement from vessels in two cases with CT of equivocal meningeal enhancement. Nonenhanced T2-weighted images were most sensitive for demonstrating ischemia/infarct and edema. Otherwise, MR images generally matched CT scans

  5. Gadolinium heteropoly complex K 17[Gd(P 2W 17O 61) 2] as a potential MRI contrast agent

    Science.gov (United States)

    Sun, Guoying; Feng, Jianghua; Wu, Huifeng; Pei, Fengkui; Fang, Ke; Lei, Hao

    2004-10-01

    Gadolinium heteropoly complex K17[Gd(P2W17O61)2] has been evaluated by in vitro and in vivo experiments as a potential contrast agent for magnetic resonance imaging (MRI). The thermal analysis and conductivity study indicate that this complex has good thermal stability and wide pH stability range. The T1 relaxivity is 7.59 mM-1 s-1 in aqueous solution and 7.97 mM-1 s-1 in 0.725 mmol l-1 bovine serum albumin (BSA) solution at 25 °C and 9.39 T, respectively. MR imaging of three male Sprague-Dawley rats showed remarkable enhancement in rat liver after intravenous injection, which persisted longer than with Gd-DTPA. The signal intensity increased by 57.1±16.9% during the whole imaging period at 0.082 mmol kg-1dose. Our preliminary in vitro and in vivo studies indicate that K17[Gd(P2W17O61)2] is a potential liver-specific MRI contrast agent.

  6. Synthesis and characterization of a porphyrazine-Gd(III) MRI contrast agent and in vivo imaging of a breast cancer xenograft model.

    Science.gov (United States)

    Trivedi, Evan R; Ma, Zhidong; Waters, Emily A; Macrenaris, Keith W; Subramanian, Rohit; Barrett, Anthony G M; Meade, Thomas J; Hoffman, Brian M

    2014-01-01

    Porphyrazines (Pz), or tetraazaporphyrins, are being studied for their potential use in detection and treatment of cancer. Here, an amphiphilic Cu-Pz-Gd(III) conjugate has been prepared via azide-alkyne Huisgen cycloaddition or 'click' chemistry between an azide functionalized Pz and alkyne functionalized DOTA-Gd(III) analog for use as an MRI contrast agent. This agent, Cu-Pz-Gd(III), is synthesized in good yield and exhibits solution-phase ionic relaxivity (r1  = 11.5 mM(-1) s(-1)) that is approximately four times higher than that of a clinically used monomeric Gd(III) contrast agent, DOTA-Gd(III). Breast tumor cells (MDA-MB-231) associate with Cu-Pz-Gd(III) in vitro, where significant contrast enhancement (9.336 ± 0.335 contrast-to-noise ratio) is observed in phantom cell pellet MR images. This novel contrast agent was administered in vivo to an orthotopic breast tumor model in athymic nude mice and MR images were collected. The average T1 of tumor regions in mice treated with 50 mg kg(-1) Cu-Pz-Gd(III) decreased relative to saline-treated controls. Furthermore, the decrease in T1 was persistent relative to mice treated with the monomeric Gd(III) contrast agent. An ex vivo biodistribution study confirmed that Cu-Pz-Gd(III) accumulates in the tumors and is rapidly cleared, primarily through the kidneys. Differential accumulation and T1 enhancement by Cu-Pz-Gd(III) in the tumor's core relative to the periphery offer preliminary evidence that this agent would find application in the imaging of necrotic tissue. Copyright © 2014 John Wiley & Sons, Ltd.

  7. Gadolinium-DTPA enhanced MRI in myocardial infarction. An experimental and clinical study

    Energy Technology Data Exchange (ETDEWEB)

    Dijkman, P.R.M. van

    1991-10-30

    This thesis focuses on one aspect of cardiac magnetic resonance imaging (MRI) for noninvasive screening of ischemic heart disease: the identification and quantification of acutely infarcted myocardium using gadolineum-diethylene triamine pentaacetic acid (Gd-DTPA) enhanced T1-weighted MRI in a clinical and experimental setting. (author). 296 refs.; 34 figs.; 4 tabs.

  8. The diagnostic value of Gd-EOB-DTPA-MRI for the diagnosis of focal nodular hyperplasia: a systematic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Chong Hyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, 88 Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Kim, Kyung Won; Shin, Yong Moon; Kim, Pyo Nyun [Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, Gene Young [University of Missouri, School of Medicine, Columbia (United States); Park, Seong Ho [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, 88 Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2015-04-01

    We aimed to systematically review the gadoxetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-MRI) findings of focal nodular hyperplasia (FNH) and its diagnostic value. A thorough literature search was conducted in Ovid-MEDLINE and EMBASE databases to identify studies evaluating Gd-EOB-DTPA-MRI findings of FNH. To evaluate the frequency of characteristic imaging findings on Gd-EOB-DTPA-MRI, pooled proportions of high/iso signal intensity (SI) on the hepatobiliary phase (HBP), arterial enhancement, high/iso SI on the portal-venous phase (PVP) or equilibrium phase (EP), and the central scar were calculated. Meta-analysis was performed to evaluate the diagnostic accuracy of high/iso SI on HBP for distinguishing FNH from hepatocellular adenoma. A review of 96 articles identified ten eligible articles with 304 patients with FNHs for meta-analysis. Pooled proportion of the Gd-EOB-DTPA-MRI findings showed that high/iso SI on the HBP, arterial enhancement, and high/iso SI on the PVP/EP were observed in 93% (95% CI, 90-97%), 99% (95% CI, 97-100%), and 97% (95% CI, 95-99%) of FNHs, respectively, while a central scar was observed in 61% of FNHs (95% CI, 47-74%). High/iso SI on the HBP was highly accurate for distinguishing FNH from hepatocellular adenoma, with a summary sensitivity of 93.9% (95% CI, 89.1-97.1%) and a specificity of 95.3% (95% CI, 88.4-98.7%). High/iso SI on the HBP of Gd-EOB-DTPA-MRI is characteristic and a prevalent finding of FNHs and can be helpful in the management of patients with FNH. (orig.)

  9. Preclinical evaluation of Gd-DTPA and gadomelitol as contrast agents in DCE-MRI of cervical carcinoma interstitial fluid pressure

    Directory of Open Access Journals (Sweden)

    Hompland Tord

    2012-11-01

    Full Text Available Abstract Background High interstitial fluid pressure (IFP in the primary tumor is associated with poor disease-free survival in locally advanced cervical carcinoma. A noninvasive assay is needed to identify cervical cancer patients with highly elevated tumor IFP because these patients may benefit from particularly aggressive treatment. It has been suggested that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI with gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA as contrast agent may provide useful information on the IFP of cervical carcinomas. In this preclinical study, we investigated whether DCE-MRI with contrast agents with higher molecular weights (MW than Gd-DTPA would be superior to Gd-DTPA-based DCE-MRI. Methods CK-160 human cervical carcinoma xenografts were subjected to DCE-MRI with Gd-DTPA (MW of 0.55 kDa or gadomelitol (MW of 6.5 kDa as contrast agent before tumor IFP was measured invasively with a Millar SPC 320 catheter. The DCE-MRI was carried out at a spatial resolution of 0.23 × 0.23 × 2.0 mm3 and a time resolution of 14 s by using a 1.5-T whole-body scanner and a slotted tube resonator transceiver coil constructed for mice. Parametric images were derived from the DCE-MRI recordings by using the Tofts iso-directional transport model and the Patlak uni-directional transport model. Results When gadomelitol was used as contrast agent, significant positive correlations were found between the parameters of both pharmacokinetic models and tumor IFP. On the other hand, significant correlations between DCE-MRI-derived parameters and IFP could not be detected with Gd-DTPA as contrast agent. Conclusion Gadomelitol is a superior contrast agent to Gd-DTPA in DCE-MRI of the IFP of CK-160 cervical carcinoma xenografts. Clinical studies attempting to develop DCE-MRI-based assays of the IFP of cervical carcinomas should involve contrast agents with higher MW than Gd-DTPA.

  10. Preclinical evaluation of Gd-DTPA and gadomelitol as contrast agents in DCE-MRI of cervical carcinoma interstitial fluid pressure.

    Science.gov (United States)

    Hompland, Tord; Ellingsen, Christine; Rofstad, Einar K

    2012-11-22

    High interstitial fluid pressure (IFP) in the primary tumor is associated with poor disease-free survival in locally advanced cervical carcinoma. A noninvasive assay is needed to identify cervical cancer patients with highly elevated tumor IFP because these patients may benefit from particularly aggressive treatment. It has been suggested that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA) as contrast agent may provide useful information on the IFP of cervical carcinomas. In this preclinical study, we investigated whether DCE-MRI with contrast agents with higher molecular weights (MW) than Gd-DTPA would be superior to Gd-DTPA-based DCE-MRI. CK-160 human cervical carcinoma xenografts were subjected to DCE-MRI with Gd-DTPA (MW of 0.55 kDa) or gadomelitol (MW of 6.5 kDa) as contrast agent before tumor IFP was measured invasively with a Millar SPC 320 catheter. The DCE-MRI was carried out at a spatial resolution of 0.23 × 0.23 × 2.0 mm³ and a time resolution of 14 s by using a 1.5-T whole-body scanner and a slotted tube resonator transceiver coil constructed for mice. Parametric images were derived from the DCE-MRI recordings by using the Tofts iso-directional transport model and the Patlak uni-directional transport model. When gadomelitol was used as contrast agent, significant positive correlations were found between the parameters of both pharmacokinetic models and tumor IFP. On the other hand, significant correlations between DCE-MRI-derived parameters and IFP could not be detected with Gd-DTPA as contrast agent. Gadomelitol is a superior contrast agent to Gd-DTPA in DCE-MRI of the IFP of CK-160 cervical carcinoma xenografts. Clinical studies attempting to develop DCE-MRI-based assays of the IFP of cervical carcinomas should involve contrast agents with higher MW than Gd-DTPA.

  11. Preclinical evaluation of Gd-DTPA and gadomelitol as contrast agents in DCE-MRI of cervical carcinoma interstitial fluid pressure

    International Nuclear Information System (INIS)

    Hompland, Tord; Ellingsen, Christine; Rofstad, Einar K

    2012-01-01

    High interstitial fluid pressure (IFP) in the primary tumor is associated with poor disease-free survival in locally advanced cervical carcinoma. A noninvasive assay is needed to identify cervical cancer patients with highly elevated tumor IFP because these patients may benefit from particularly aggressive treatment. It has been suggested that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA) as contrast agent may provide useful information on the IFP of cervical carcinomas. In this preclinical study, we investigated whether DCE-MRI with contrast agents with higher molecular weights (MW) than Gd-DTPA would be superior to Gd-DTPA-based DCE-MRI. CK-160 human cervical carcinoma xenografts were subjected to DCE-MRI with Gd-DTPA (MW of 0.55 kDa) or gadomelitol (MW of 6.5 kDa) as contrast agent before tumor IFP was measured invasively with a Millar SPC 320 catheter. The DCE-MRI was carried out at a spatial resolution of 0.23 × 0.23 × 2.0 mm 3 and a time resolution of 14 s by using a 1.5-T whole-body scanner and a slotted tube resonator transceiver coil constructed for mice. Parametric images were derived from the DCE-MRI recordings by using the Tofts iso-directional transport model and the Patlak uni-directional transport model. When gadomelitol was used as contrast agent, significant positive correlations were found between the parameters of both pharmacokinetic models and tumor IFP. On the other hand, significant correlations between DCE-MRI-derived parameters and IFP could not be detected with Gd-DTPA as contrast agent. Gadomelitol is a superior contrast agent to Gd-DTPA in DCE-MRI of the IFP of CK-160 cervical carcinoma xenografts. Clinical studies attempting to develop DCE-MRI-based assays of the IFP of cervical carcinomas should involve contrast agents with higher MW than Gd-DTPA

  12. Volume-assisted estimation of liver function based on Gd-EOB-DTPA-enhanced MR relaxometry

    Energy Technology Data Exchange (ETDEWEB)

    Haimerl, Michael; Schlabeck, Mona; Verloh, Niklas; Fellner, Claudia; Stroszczynski, Christian; Wiggermann, Philipp [University Hospital Regensburg, Department of Radiology, Regensburg (Germany); Zeman, Florian [University Hospital Regensburg, Center for Clinical Trials, Regensburg (Germany); Nickel, Dominik [MR Applications Development, Siemens AG, Healthcare Sector, Erlangen (Germany); Barreiros, Ana Paula [University Hospital Regensburg, Department of Internal Medicine I, Regensburg (Germany); Loss, Martin [University Hospital Regensburg, Department of Surgery, Regensburg (Germany)

    2016-04-15

    To determine whether liver function as determined by indocyanine green (ICG) clearance can be estimated quantitatively from hepatic magnetic resonance (MR) relaxometry with gadoxetic acid (Gd-EOB-DTPA). One hundred and seven patients underwent an ICG clearance test and Gd-EOB-DTPA-enhanced MRI, including MR relaxometry at 3 Tesla. A transverse 3D VIBE sequence with an inline T1 calculation was acquired prior to and 20 minutes post-Gd-EOB-DTPA administration. The reduction rate of T1 relaxation time (rrT1) between pre- and post-contrast images and the liver volume-assisted index of T1 reduction rate (LVrrT1) were evaluated. The plasma disappearance rate of ICG (ICG-PDR) was correlated with the liver volume (LV), rrT1 and LVrrT1, providing an MRI-based estimated ICG-PDR value (ICG-PDR{sub est}). Simple linear regression model showed a significant correlation of ICG-PDR with LV (r = 0.32; p = 0.001), T1{sub post} (r = 0.65; p < 0.001) and rrT1 (r = 0.86; p < 0.001). Assessment of LV and consecutive evaluation of multiple linear regression model revealed a stronger correlation of ICG-PDR with LVrrT1 (r = 0.92; p < 0.001), allowing for the calculation of ICG-PDR{sub est}. Liver function as determined using ICG-PDR can be estimated quantitatively from Gd-EOB-DTPA-enhanced MR relaxometry. Volume-assisted MR relaxometry has a stronger correlation with liver function than does MR relaxometry. (orig.)

  13. Added value of Gd-EOB-DTPA-enhanced Hepatobiliary phase MR imaging in evaluation of focal solid hepatic lesions

    International Nuclear Information System (INIS)

    Haimerl, Michael; Wächtler, Max; Platzek, Ivan; Müller-Wille, Rene; Niessen, Christoph; Hoffstetter, Patrick; Schreyer, Andreas Georg; Stroszczynski, Christian; Wiggermann, Philipp

    2013-01-01

    Correct characterization of focal solid hepatic lesions has always been a challenge and is of great diagnostic and therapeutic relevance. The purpose of this study was to determine the added value of hepatobiliary phase images in Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) for differentiating focal solid hepatic lesions. In this retrospective trial 84 consecutive patients underwent Gd-EOB-DTPA-enhanced MR examinations. MRI was conducted for 64 patients with malignant focal hepatic lesions (34 hepatocellular carcinoma (HCC), 30 metastases) and for 20 patients with benign hepatic lesions (14 focal nodular hyperplasia (FNH), 3 adenoma, 3 hemangioma). Five radiologists independently reviewed three sets of MR images by means of a 5-point confidence scale from score 1 (definitely benign) to score 5 (definitely malignant): set 1: unenhanced images; set 2: unenhanced and Gd-EOB-DTPA-enhanced dynamic images; set 3: hepatobiliary phase images in addition to set 2. Accuracy was assessed by the alternative free-response receiver operating characteristic curve (A z ) and the index of diagnostic performance was calculated. Diagnostic accuracy was significantly improved by the addition of Gd-EOB-DTPA-enhanced dynamic images: A z in set 1 was 0.708 and 0.833 in set 2 (P = 0.0002). The addition of hepatobiliary phase images increased the A z value to 0.941 in set 3 (set 3 vs set 2, P < 0.0001; set 3 vs set 1, P < 0.0001). The index of diagnostic performance was lowest in set 1 (45%), improved in set 2 (71%), and highest in set 3 (94%). Hepatobiliary phase images obtained after Gd-EOB-DTPA-enhanced dynamic MRI improve the differentiation of focal solid hepatic lesions

  14. Gd-DTPA-enhanced MR imaging in facial nerve paralysis

    International Nuclear Information System (INIS)

    Tien, R.D.; Dillon, W.P.

    1989-01-01

    GD-DTPA-enhanced MR imaging was used to evaluate 11 patients with facial nerve paralysis (five acute idiopathic facial palsy (Bell palsy), three chronic recurrent facial palsy, one acute facial palsy after local radiation therapy, one chronic facial dyskinesia, and one facial neuroma). In eight of 11 patients, there was marked enhancement of the infratemporal facial nerve from the labyrinthine segment to the stylomastoid foramen. Two patients had additional contrast enhancement in the internal auditory canal segment. In one patient, enhancement persisted (but to a lesser degree) 8 weeks after symptoms had resolved. In one patient, no enhancement was seen 15 months after resolution of Bell palsy. The facial neuroma was seen as a focal nodular enhancement in the mastoid segment of the facial nerve

  15. Synergistic effect of Al and Gd on enhancement of mechanical properties of magnesium alloys

    Directory of Open Access Journals (Sweden)

    Bita Pourbahari

    2017-04-01

    Full Text Available The effect of Gd/Al ratio on the properties of as-cast Mg-Gd-Al-Zn alloys was investigated by changing the chemical composition from that of AZ61 to GZ61. At the ratio of 1, the Al2Gd phase becomes predominant and Mg17Al12 is hardly seen in the microstructure. As a potent inoculant, the Al2Gd phase resulted in intense grain refinement and enhancement of strength, ductility and toughness. For instance, the tensile strength and elongation to failure of Mg-3Gd-3Al-1Zn alloy were enhanced by ~4% and 180% compared with those of AZ61 alloy, respectively. However, at high Gd/Al ratios, the Al2Gd phase was replaced by (Mg,Al3Gd and Mg5Gd phases and very large grain sizes were achieved, which led to poor tensile properties and the appearance of cleavage facets on the fracture surfaces. Therefore, it can be deduced that the presence of Gd and Al, in appropriate amounts to reach Gd/Al ratio of ~ 1, is required for the achievement of grain refinement, good ductility, high strength, and the appearance of ductile fracture surfaces in the Mg-Gd-Al-Zn system. Conclusively, the Mg-Gd-Al-Zn alloys can be considered as a new class of structural magnesium alloy and it is superior to both AZ (Mg-Al-Zn and GZ (Mg-Gd-Zn series of alloys.

  16. A simple polyol-free synthesis route to Gd2O3 nanoparticles for MRI applications: an experimental and theoretical study

    International Nuclear Information System (INIS)

    Ahrén, Maria; Selegård, Linnéa; Söderlind, Fredrik; Linares, Mathieu; Kauczor, Joanna; Norman, Patrick; Käll, Per-Olov; Uvdal, Kajsa

    2012-01-01

    Chelated gadolinium ions, e.g., Gd-DTPA, are today used clinically as contrast agents for magnetic resonance imaging (MRI). An attractive alternative contrast agent is composed of gadolinium oxide nanoparticles as they have shown to provide enhanced contrast and, in principle, more straightforward molecular capping possibilities. In this study, we report a new, simple, and polyol-free way of synthesizing 4–5-nm-sized Gd 2 O 3 nanoparticles at room temperature, with high stability and water solubility. The nanoparticles induce high-proton relaxivity compared to Gd-DTPA showing r 1 and r 2 values almost as high as those for free Gd 3+ ions in water. The Gd 2 O 3 nanoparticles are capped with acetate and carbonate groups, as shown with infrared spectroscopy, near-edge X-ray absorption spectroscopy, X-ray photoelectron spectroscopy and combined thermogravimetric and mass spectroscopy analysis. Interpretation of infrared spectroscopy data is corroborated by extensive quantum chemical calculations. This nanomaterial is easily prepared and has promising properties to function as a core in a future contrast agent for MRI.

  17. A simple polyol-free synthesis route to Gd2O3 nanoparticles for MRI applications: an experimental and theoretical study

    Science.gov (United States)

    Ahrén, Maria; Selegård, Linnéa; Söderlind, Fredrik; Linares, Mathieu; Kauczor, Joanna; Norman, Patrick; Käll, Per-Olov; Uvdal, Kajsa

    2012-08-01

    Chelated gadolinium ions, e.g., Gd-DTPA, are today used clinically as contrast agents for magnetic resonance imaging (MRI). An attractive alternative contrast agent is composed of gadolinium oxide nanoparticles as they have shown to provide enhanced contrast and, in principle, more straightforward molecular capping possibilities. In this study, we report a new, simple, and polyol-free way of synthesizing 4-5-nm-sized Gd2O3 nanoparticles at room temperature, with high stability and water solubility. The nanoparticles induce high-proton relaxivity compared to Gd-DTPA showing r 1 and r 2 values almost as high as those for free Gd3+ ions in water. The Gd2O3 nanoparticles are capped with acetate and carbonate groups, as shown with infrared spectroscopy, near-edge X-ray absorption spectroscopy, X-ray photoelectron spectroscopy and combined thermogravimetric and mass spectroscopy analysis. Interpretation of infrared spectroscopy data is corroborated by extensive quantum chemical calculations. This nanomaterial is easily prepared and has promising properties to function as a core in a future contrast agent for MRI.

  18. The synthesis of a D-glucosamine contrast agent, Gd-DTPA-DG, and its application in cancer molecular imaging with MRI

    International Nuclear Information System (INIS)

    Zhang Wei; Chen Yue; Guo Dajing; Huang Zhanwen; Cai Liang; He Ling

    2011-01-01

    Objective: The purpose of this study is to describe the synthesis of Gadolinium-diethylenetriamine pentaacetic acid-deoxyglucosamine (Gd-DTPA-DG) which is a D-glucosamine metabolic MR imaging contrast agent. We will also discuss its use in a pilot MRI study using a xenograft mouse model of human adenocarcinoma. Methods: This novel contrast agent was specifically studied because of its ability to 'target' metabolically active tumor tissues. In this study Gd-DTPA-DG is used to investigate how tumor tissues would react to a dose of 0.2 mmol Gd/kg over a 120 min exposure in a xenograft mouse model. These experiments used athymic mice implanted with human pulmonary adenocarcinoma (A549) as demonstrated by dynamic MRI. Alternately, another contrast agent that is not specific for targeting, Gd-DTPA, was used as the control at a similar dose of gadolinium. Efficacy of the targeted contrast agent was assessed by measuring relaxation rate in vitro and signal intensity (SI) in vivo. Statistical differences were calculated using one-way analysis of variance. Results: The synthesized Gd-DTPA-DG was shown to improve the contrast of tumor tissue in this model. Gd-DTPA-DG was also shown to have a similar pharmacokinetic rate but generated a higher relaxation rate in tumor tissues relative to the control contrast Gd-DTPA. In comparison to the pre-contrast imaging, the SI of tumor tissue in the experimental group was shown to be significantly increased at 15 min after injection of Gd-DTPA-DG (p < 0.001). The enhanced signal intensity spread from the edge of the tumor to the center and seemed to strengthen the idea that MRI performance would be useful in different tumor tissues. Conclusion: This preliminary study shows that this new chelated contrast agent, Gd-DTPA-DG, can be specifically targeted to accumulation in tumor tissue as compared to normal tissues. This targeted paramagnetic contrast agent has potential for specific cancer molecular imaging with MRI.

  19. Enhanced MRI in patients with Ramsay-Hunt's syndrome

    International Nuclear Information System (INIS)

    Yanagida, Masahiro; Ushiro, Koichi; Yamashita, Toshio; Kumazawa, Tadami; Katoh, Tsutomu

    1993-01-01

    Enhanced MRI was performed in 14 patients with Ramsay-Hunt,s syndrome to investigate the pathogenesis of this syndrome. All MRI studies were performed on a 0.5T superconductivity MRI system using a head coil with Gd-DTPA. Enhancement was observed in the areas of the distal internal auditory canal and labyrinthine segment in many patients, and was especially prominent in patients suffering from vertigo, tinnitus, and hearing loss. In some patients it involved not only the facial nerve of the internal auditory canal but also the cochlear nerve and vestibular nerves. Since histological changes of the facial nerve in patients with Ramsay-Hunt's syndrome are assumed to occur in the distal internal auditory canal and labyrinthine segment, which is more proximal than the geniculate ganglion, and the possibility is suggested that inflammation may be spread to the vestibular and cochlear nerve via the internal auditory canal. (14 refs., 2 figs.)

  20. Enhanced MRI in patients with Ramsay-Hunt's syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Masahiro; Ushiro, Koichi; Yamashita, Toshio; Kumazawa, Tadami [Kansai Medical Univ., Osaka (Japan). Dept. of Otolaryngology; Katoh, Tsutomu [Kansai Medical Univ., Osaka (Japan). Dept. of Radiology

    1993-01-01

    Enhanced MRI was performed in 14 patients with Ramsay-Hunt,s syndrome to investigate the pathogenesis of this syndrome. All MRI studies were performed on a 0.5T superconductivity MRI system using a head coil with Gd-DTPA. Enhancement was observed in the areas of the distal internal auditory canal and labyrinthine segment in many patients, and was especially prominent in patients suffering from vertigo, tinnitus, and hearing loss. In some patients it involved not only the facial nerve of the internal auditory canal but also the cochlear nerve and vestibular nerves. Since histological changes of the facial nerve in patients with Ramsay-Hunt's syndrome are assumed to occur in the distal internal auditory canal and labyrinthine segment, which is more proximal than the geniculate ganglion, and the possibility is suggested that inflammation may be spread to the vestibular and cochlear nerve via the internal auditory canal. (14 refs., 2 figs.).

  1. Evaluation of meningeal enhancement with Gd-DTPA

    International Nuclear Information System (INIS)

    Phillips, M.; Ryals, T.J.; Yuh, W.T.C.; Kambho, S.

    1989-01-01

    Forty-three consecutive patients (16 with tumor, 11 with inflammation, 16 postoperative) with abnormal meningeal enhancement were studied. Positive pathology was obtained in 75% of tumors and 100% of inflammatory conditions. Pial enhancement was demonstrated in seven of 11 patients with inflammation, four of 16 with tumor, and two of 16 postoperative patients. Diffuse meningeal enhancement was most commonly present with neoplastic and inflammatory etiologies. Localized enhancement predominated in the postoperative population, unless complicated by a subdural hematoma. A nodular appearance was present in two patients with tumor. In conclusion, Gd-DTPA MR imaging is sensitive to but not specific of meningeal pathology. MR imaging is better in inflammatory than in neoplastic conditions

  2. Preclinical evaluation of Gd-DTPA and gadomelitol as contrast agents in DCE-MRI of cervical carcinoma interstitial fluid pressure

    OpenAIRE

    Hompland Tord; Ellingsen Christine; Rofstad Einar K

    2012-01-01

    Abstract Background High interstitial fluid pressure (IFP) in the primary tumor is associated with poor disease-free survival in locally advanced cervical carcinoma. A noninvasive assay is needed to identify cervical cancer patients with highly elevated tumor IFP because these patients may benefit from particularly aggressive treatment. It has been suggested that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium diethylene-triamine penta-acetic acid (Gd-DTPA) as c...

  3. Enhanced MRI in patients with facial palsy; Study of time-related enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Masahiro; Kato, Tsutomu; Ushiro, Koichi; Kitajiri, Masanori; Yamashita, Toshio; Kumazawa, Tadami; Tanaka, Yoshimasa (Kansai Medical School, Moriguchi, Osaka (Japan))

    1991-03-01

    We performed Gd-DTPA-enhanced magnetic resonance imaging (MRI) examinations at several stages in 40 patients with peripheral facial nerve palsy (Bell's palsy and Ramsay-Hunt syndrome). In 38 of the 40 patients, one and more enhanced region could be seen in certain portion of the facial nerve in the temporal bone on the affected side, whereas no enhanced regions were seen on the intact side. Correlations between the timing of the MRI examination and the location of the enhanced regions were analysed. In all 6 patients examined by MRI within 5 days after the onset of facial nerve palsy, enhanced regions were present in the meatal portion. In 3 of the 8 patients (38%) examined by MRI 6 to 10 days after the onset of facial palsy, enhanced areas were seen in both the meatal and labyrinthine portions. In 8 of the 9 patients (89%) tested 11 to 20 days after the onset of palsy, the vertical portion was enhanced. In the 12 patients examined by MRI 21 to 40 days after the onset of facial nerve palsy, the meatal portion was not enhanced while the labyrinthine portion, the horizontal portion and the vertical portion were enhanced in 5 (42%), 8 (67%) and 11 (92%), respectively. Enhancement in the vertical portion was observed in all 5 patients examined more than 41 days after the onset of facial palsy. These results suggest that the central portion of the facial nerve in the temporal bone tends to be enhanced in the early stage of facial nerve palsy, while the peripheral portion is enhanced in the late stage. These changes of Gd-DTPA enhanced regions in the facial nerve may suggest dromic degeneration of the facial nerve in peripheral facial nerve palsy. (author).

  4. Gd-DTPA-enhanced MR in thoracic disc herniations

    International Nuclear Information System (INIS)

    Parizel, P.M.; Rodesch, G.; Baleriaux, D.; Segebarth, C.; Zegers de Beyl, D.; Haens, J. d'; Noterman, J.

    1989-01-01

    The Gd-DTPA-enhanced magnetic resonance findings in two patients with herniated thoracic intervertebral discs are reported. The first patient was a 56-year-old woman with a small subligamentous T6-7 disc herniation, slightly lateralized to the right. The second patient was a 51-year-old man with a central and right posterolateral disc herniation, including a large calcified fragment, at the T8-9 level. The nonenhanced MR examination revealed the presence of an extradural mass lesion in both patients, impinging upon the dural sac and compressing and displacing the spinal cord posteriorly. The lesion was slightly hypointense on both T1- and T2-weighted spin echo sequences. Following intravenous injection of Gd-DTPA in a dosage of 0.1 mmol/kg body weight, enhancement of the posterior longitudinal ligament was noted and triangular areas of contrast uptake were seen to occur in the epidural space above and below the herniated disc. At surgery, they were found to correspond to dilated and congested epidural veins. (orig.)

  5. Haemophilic arthropathy of the knee. Gd-DTPA enhanced MRT. Clinical and radiological correlation

    International Nuclear Information System (INIS)

    Naegele, M.; Kunze, V.; Hamann, M.; Eickhoff, H.; Koch, W.; Oldenburg, J.; Reiser, M.

    1994-01-01

    17 patients with hemophilic arthropathy of the knee joint were studied with static and dynamic MRT before and after i.v. bolus injection of Gadolinium-DTPA (0,1 mmol/kg body weight). After contrast enhancement, synovial proliferations exhibited an increase of signal intensity (SI) of FFE and SE images of 47.7% and 37.4% respectively, whereas muscle and fatty tissue, tendons, bone marrow and joint effusion revealed only minor increase in SI. The gradient of signal intensity (ratio SI/time) of pannus was 39,6% min. Gd-DTPA enhanced MRI studies delineate and quantify the synovial proliferations in hemophilic arthropathy. Dynamic studies in hemophilic arthropathy do not provide qualitative assessment of the inflammatory process. (orig.) [de

  6. Enhancement MRI evaluation of neuroblastoma staging in children

    International Nuclear Information System (INIS)

    Li Xin; Wang Chunxiang; Zhao Bin; Liu Peifang

    2002-01-01

    Objective: To evaluate the value and limitation of Gd-DTPA enhanced MRI for neuroblastoma staging in children. Methods: Twelve cases of neuroblastoma proved by operation or bone marrow aspiration were examined by gadolinium-enhanced MRI. The age ranged from seven months to five years, mean 3.7 years. Eight tumors originated from adrenal, and four from posterior mediastinum. Conventional sequences, double dose gadolinium-enhanced MRI, and 3D CEMRA were used in all patients. Six cases were examined by CT in same time. Imaging staging on surgic-histopathological-based International Neuroblastoma Staging System (INSS) was performed. Results: Six patients were staged by CT, including stage I-II in 2 cases, stage III in 4 cases, and stage IV in none. Twelve patients were staged by conventional MRI, including stage I-II in 2 cases, stage III in 9 cases, and stage IV in 1 case. Twelve patients were staged by double dose gadolinium-enhanced MRI, including stage I-II in 1 case, stage III in 1 case, and stage IV in 10 cases. Conclusion: Gadolinium-enhanced MRI was a single best imaging modality for neuroblastoma, most useful for distal to diaphragm metastasis, dumbbell tumor intraspinal extension, and bone marrow metastasis that was not detected by aspirate examination. Enhancement MRI was important in evaluating the therapy and was also helpful in assessing the therapeutic efficacy and relapse. 3D CEMRA helps demonstrate large vascular encasement and tumor erosion into important organs, and it is useful in assessing the respectability. Long examination time and lack in showing the characteristic calcium were the limitations

  7. Clinical experience of adverse drug reaction in gadolinium-DTPA enhancement of MRI

    International Nuclear Information System (INIS)

    Kim, Mi Hyae; Hong, Ju Hee; Lee, Yeon Su; Cha, Kyung Soo; Chang, Suk Il; Lee, Young Chul; Kim, Yeong Soo

    1992-01-01

    Gadopentetate dimenglumine(Gd-DTPA) has low toxicity and good tolerance and it is said that the observed adverse drug reaction of Gd-DTPA is compatible to those of iodinated nonionic contrast media. The overall incidence of adverse drug reaction of Gd-DTPA is even lower than those of iodinated nonionic contrast media. Then, the possibility of potential adverse drug reaction of these contrast media is not fully known and recently, many authors have a growing interest in this point. We have taken 2501 cases of MRI and executed 1467 case of Gd-DTPA enhancement scanning(58.7%) and experienced 12 cases of adverse drug reaction(11 cases: mild reaction, 1 case: severs anaphylactic shock) and the overall incidence of our adverse drug reaction of Gd-DTPA was 0.8%. In conclusion, the adverse drug reaction of Gd-DTPA is not rare and the severe adverse drug reaction of Gd-DTPA may occur. So, the possibility of adverse drug reaction after Gd-DTPA injection should always be kept in mind, especially when the patient has a history of reaction to contrast material, allergy(particularly asthma) and cardiac disease. For the safe use of Gd-DTPA, well trained personnel and nearby emergent care facilities should be available

  8. Synergistic enhancement of iron oxide nanoparticle and gadolinium for dual-contrast MRI

    International Nuclear Information System (INIS)

    Zhang, Fan; Huang, Xinglu; Qian, Chunqi; Zhu, Lei; Hida, Naoki; Niu, Gang; Chen, Xiaoyuan

    2012-01-01

    Highlights: ► MR contrast agents exert influence on T 1 or T 2 relaxation time of the surrounding tissue. ► Combined use of iron oxide and Gd-DTPA can improve the sensitivity/specificity of lesion detection. ► Dual contrast MRI enhances the delineation of tumor borders and small lesions. ► The effect of DC-MRI can come from the high paramagnetic susceptibility of Gd 3+ . ► The effect of DC-MRI can also come from the distinct pharmacokinetic distribution of SPIO and Gd-DTPA. -- Abstract: Purpose: The use of MR contrast agents allows accurate diagnosis by exerting an influence on the longitudinal (T 1 ) or transverse (T 2 ) relaxation time of the surrounding tissue. In this study, we combined the use of iron oxide (IO) particles and nonspecific extracellular gadolinium chelate (Gd) in order to further improve the sensitivity and specificity of lesion detection. Procedures: With a 7-Tesla scanner, pre-contrasted, IO-enhanced and dual contrast agent enhanced MRIs were performed in phantom, normal animals, and animal models of lymph node tumor metastases and orthotopic brain tumor. For the dual-contrast (DC) MRI, we focused on the evaluation of T 2 weighted DC MRI with IO administered first, then followed by the injection of a bolus of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA). Results: Based on the C/N ratios and MRI relaxometry, the synergistic effect of coordinated administration of Gd-DTPA and IO was observed and confirmed in phantom, normal liver and tumor models. At 30 min after administration of Feridex, Gd-DTPA further decreased T 2 relaxation in liver immediately after the injection. Additional administration of Gd-DTPA also immediately increased the signal contrast between tumor and brain parenchyma and maximized the C/N ratio to −4.12 ± 0.71. Dual contrast MRI also enhanced the delineation of tumor borders and small lesions. Conclusions: DC-MRI will be helpful to improve diagnostic accuracy and decrease the threshold size for

  9. Recurrent medulloblastoma: Frequency of tumor enhancement on Gd-DTPA MR imaging

    International Nuclear Information System (INIS)

    Rollins, N.; Mendelsohn, D.; Mulne, A.; Barton, R.; Diehl, J.; Reyes, N.; Sklar, F.

    1990-01-01

    Thirty-two children with medulloblastoma were evaluated postoperatively with conventional and gadolinium-enhanced MR imaging. Eleven patients had abnormal cranial MR studies; nine of these had recurrent tumor. In six patients recurrent tumor enhanced with Gd, while in the other three patients recurrent tumor did not enhance. The remaining two patients had areas of abnormal Gd enhancement that were caused by radiation-induced breakdown of the blood-brain barrier rather than by recurrent tumor. This study shows that not all recurrent medulloblastoma enhances and that the absence of Gd enhancement does not necessarily indicate the absence of recurrent tumor

  10. Assessment of the link between quantitative biexponential diffusion-weighted imaging and contrast-enhanced MRI in the liver

    NARCIS (Netherlands)

    Dijkstra, Hildebrand; Oudkerk, Matthijs; Kappert, Peter; Sijens, Paul E.

    Purpose: To investigate if intravoxel incoherent motion (IVIM) modeled diffusion-weighted imaging (DWI) can be linked to contrast-enhanced (CE-)MRI in liver parenchyma and liver lesions. Methods: Twenty-five patients underwent IVIM-DWI followed by multiphase CE-MRI using Gd-EOB-DTPA (n = 20) or

  11. Gd-DTPA enhanced MR imaging in Bell's palsy

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Yasushi; Kawamura, Yuji (Takanoko Hospital, Matsuyama, Ehime (Japan)); Yanagihara, Naoaki; Sadamoto, Masanori; Sadamoto, Kazuhiko

    1991-09-01

    Magnetic resonance imaging (MRI) was carried out in 27 patients with Bell's palsy. T1-weighted spin-echo images (TR500/TE25-34) were taken before and after the intravenous administration of Gd-DTPA (0.1 mmol/kg) with 0.5T superconductive MRI. There was significant enhancement at the geniculate ganglion and the horizontal segment of the involved facial nerve in 22 patients (81.5%) and at the vertical segment in 20 (74.1%). Enhancement at the meatal fundus was seen in only 4 patients (14.9%) and at the labyrinthine segment in 8 (29.6%). These results corroborate other evidence that the geniculate ganglion is involved most frequently in Bell's palsy. In addition, the enhancement of the proximal portion, i.e. the meatal fundus and the labyrinthine segment of the nerve, although not common, noted in this study may be important in the diagnosis and treatment of Bell's palsy. (author).

  12. MR imaging of the breast with Gd-DTPA enhancement

    International Nuclear Information System (INIS)

    Hachiya, Junichi; Seki, Tsuneaki; Okada, Minoru; Nitatori, Toshiaki; Korenaga, Tateo; Furuya, Yoshiro

    1991-01-01

    The accuracy of MR imaging with Gd-DTPA enhancement was compared with mammography and ultrasonography in 52 patients with clinically palpable benign and malignant breast masses (36 carcinomas, 2 malignant phyllodes tumors, 7 fibroadenomas, 7 cysts). On dynamic MR imaging, carcinomas and fibroadenomas were discriminated by their different dynamic enhancement profiles. In carcinomas, signal intensity increased rapidly, reaching a peak or plateau within 2 min after the injection of contrast medium. In fibroadenomas, signal intensity showed a much slower continuous increase without ceasing until about 8 min after injection. Malignant phyllodes tumors showed a dynamic enhancement profile identical to that of benign fibroadenomas. MR imaging correctly identified 84% of malignant tumors, 86% of fibroadenomas, and 100% of cysts, and was substantially more accurate in tissue characterization than mammography. The results of ultrasonography were highly similar to those of MR imaging. However, no single modality was infallible, and the three modalities were complementary rather than competitive. Considering the high cost and long examination time of MR imaging, mammography supplemented by ultrasonography seems to be the method of choice in the diagnosis of breast lesions. Nevertheless, MR imaging can add important information when the results of mammography and ultrasonography are insufficient or contradictory. (author)

  13. Quantification of synovistis by MRI: correlation between dynamic and static gadolinium-enhanced magnetic resonance imaging and microscopic and macroscopic signs of synovial inflammation

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Stoltenberg, M; Løvgreen-Nielsen, P

    1998-01-01

    Dynamic and static gadolinium-diethylenetriaminepentaacetic acid(Gd-DTPA)-enhanced magnetic resonance imaging (MRI) were evaluated as measures of joint inflammation in arthritis, by a comparison with macroscopic and microscopic signs of synovitis. Furthermore, the importance of the size...

  14. Enhanced room temperature multiferroicity in Gd doped BFO

    CSIR Research Space (South Africa)

    Pradhan, SK

    2009-01-01

    Full Text Available deficient Gd doped multiferroic BFO system. At particular doping level of Gd, this bulk ceramics showed spectacular M~H behavior at room temperature which is likely to open a new avenue for the potential applications in information storing technology as well...

  15. First-pass perfusion disturbance of coronary artery stenosis: an experimental study using MR imaging with Gd-DTPA enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Kyung Il; Lee, Young Ju [Ajou Univ. College of Medicine, Seoul (Korea, Republic of); Lim, Tae Hwan [Ulsan Univ. College of Medicine, Ulsan (Korea, Republic of)] [and others

    1997-11-01

    In order to determine the value of first-pass MR imaging in the diagnosis of myocardial ischemia, first-pass perfusion abnormality of coronary artery stenosis was observed in MRI after gadopentate dimeglumine(GD-DTPA) enhancement. The left anterior descending(LAD) coronary arteries of six dogs were subjected to approximately 70% stenosis confirmed by coronary angiography. Half an hour after adenosine and {sup 99m}Tc-sestamibi infusion, Gd-DTPA(0.2mmol/kg) and methylene blue were administered and termination was induced with potassium chloride. SE T1-weighted and single-photon emission computed tomography(SPECT) images were subsequently obtained and the findings of perfusion defect compared with specimen stain. Three dimensionally reconstructed MR images were used to measure signal intensity(SI) of normal myocardium and perfusion defect from their sectional and total volume. Five of six dogs with LAD artey stenosis ranging from 66% to 73% displayed perfusion defect on MRI, SPECT, and specimen stain, but the remaining dog with stenosis of 58% showed no such defect. MRI showed the perfusion defect as distinct low SI, enabling the measurement of percentage perfusion defect(24.4{+-}5.4%), which increased inferiorly. SI of normal myocardium and perfusion defect decreased inferiorly; their difference indicated stenosis-induced perfusion loss according to section location. Volumetric SI of normal myocardium and perfusion defect were 3.42{+-}0.52 and 2.16{+-}0.45, respectively(p<0.05). Gd-DTPA enhanced MRI displayed first-pass perfusion abnormality of coronary artery stenosis as perfusion defect with distinct low SI; this enabled the measurement of its volume and SI changes according to section location, and thus indicated the value of first-pass MR imaging in the diagnosis of myocardial ischemia.

  16. First-pass perfusion disturbance of coronary artery stenosis: an experimental study using MR imaging with Gd-DTPA enhancement

    International Nuclear Information System (INIS)

    Chung, Kyung Il; Lee, Young Ju; Lim, Tae Hwan

    1997-01-01

    In order to determine the value of first-pass MR imaging in the diagnosis of myocardial ischemia, first-pass perfusion abnormality of coronary artery stenosis was observed in MRI after gadopentate dimeglumine(GD-DTPA) enhancement. The left anterior descending(LAD) coronary arteries of six dogs were subjected to approximately 70% stenosis confirmed by coronary angiography. Half an hour after adenosine and 99m Tc-sestamibi infusion, Gd-DTPA(0.2mmol/kg) and methylene blue were administered and termination was induced with potassium chloride. SE T1-weighted and single-photon emission computed tomography(SPECT) images were subsequently obtained and the findings of perfusion defect compared with specimen stain. Three dimensionally reconstructed MR images were used to measure signal intensity(SI) of normal myocardium and perfusion defect from their sectional and total volume. Five of six dogs with LAD artey stenosis ranging from 66% to 73% displayed perfusion defect on MRI, SPECT, and specimen stain, but the remaining dog with stenosis of 58% showed no such defect. MRI showed the perfusion defect as distinct low SI, enabling the measurement of percentage perfusion defect(24.4±5.4%), which increased inferiorly. SI of normal myocardium and perfusion defect decreased inferiorly; their difference indicated stenosis-induced perfusion loss according to section location. Volumetric SI of normal myocardium and perfusion defect were 3.42±0.52 and 2.16±0.45, respectively(p<0.05). Gd-DTPA enhanced MRI displayed first-pass perfusion abnormality of coronary artery stenosis as perfusion defect with distinct low SI; this enabled the measurement of its volume and SI changes according to section location, and thus indicated the value of first-pass MR imaging in the diagnosis of myocardial ischemia

  17. Hepatic enhancement on Gd-BOPTA-enhanced MR imaging: comparison between cirrhotic and normal livers

    International Nuclear Information System (INIS)

    Shin, Sang Soo; Jeong, Yong Yeon; Kang, Heoung Keun; Lim, Hyo Soon; Yoon, Woong; Seo, Jeong Jin; Park, Jin Gyoon

    2004-01-01

    To compare the enhancement features of hepatic parenchyma between cirrhotic and normal liver, using Gd-BOPTA-enhanced delayed MR imaging. The 60 patients (35 with cirrhotic and 25 with normal liver) included in our study underwent Gd-BOPTA-enhanced MR imaging using a 1.5T system with a phase-array multicoil. In all cases, T1-weighted in-phase and opposed-phase gradient-echo MR imaging was performed before and 60 minutes after intravenous administration of a bolus of Gd-BOPTA. All images were quantitatively analysed by comparing the signal-to-noise ratio (SNR) and signal enhancement (SE) of cirrhotic and normal liver before and after contrast enhancement, and in cirrhotic patients, SNR and SE were also compared in terms of the Child-Pugh classification. For qualitative analysis, the hepatic enhancement patterns of cirrhotic and normal liver were classified as homogeneous or heterogeneous according to the consensual findings of two radiologists. At contrast-enhanced imaging, both cirrhotic (p<0.001) and normal liver (p<0.001) showed substantially increased SNR relative to unenhanced images, and the SNR of cirrhotic liver was significantly lower than that of normal livers at both in-phase (p<0.001) and opposed-phase (p<0.001) imaging. The SE of cirrhotic liver was significantly lower than that of normal liver (in-phase:p=0.002; opposed phase:p=0.011). Both Child-Pugh class A (p<0.001) and B (p<0.001) cirrhotic liver showed a substantial increase in SNR at contrast-enhanced imaging relative to unenhanced imaging and the SNR of Child-Pugh class A was significantly higher than that of Child-Pugh class B at both in-phase (p<0.001) and opposed-phase (p=0.022) imaging. In addition, the SE of class A was significantly higher than that of class B at in-phase imaging (p=0.004). Cirrhotic liver showed heterogeneous enhancement in 20 of 35 patients (57%), whereas normal liver showed homogeneous enhancement in all patients. At Gd-BOPTA-enhanced delayed MR imaging, cirrhotic liver

  18. Gd-EOB-DTPA-enhanced-MR imaging in the inflammation stage of nonalcoholic steatohepatitis (NASH) in mice.

    Science.gov (United States)

    Yamada, Tomomi; Obata, Atsushi; Kashiwagi, Yuto; Rokugawa, Takemi; Matsushima, Shuuichi; Hamada, Tadateru; Watabe, Hiroshi; Abe, Kohji

    2016-07-01

    The purpose of this study is to investigate the correlation between the liver kinetics of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) and liver histopathology in a mouse model of NASH by using dynamic contrast-enhanced MRI. Twenty male C57/BL6 mice aged 8weeks were fed a methionine-choline-deficient (MCD) diet for 2, 4 and 6weeks (MCD groups: MCD 2w, 4w, or 6w). Gd-EOB-DTPA-enhanced MR imaging of the liver was performed at 2, 4 and 6weeks after the MCD feeding. The signal intensity of the liver was obtained from dynamic MR images and relative enhancement (RE), and the time to maximum RE (Tmax) and half-life of elimination RE (T1/2) were calculated. After MRI scan, histopathological scores of hepatic steatosis and inflammation and blood biochemistry data, such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, were obtained. Plasma AST and ALT levels were significantly increased in mice fed MCD. Histopathological scores indicated that steatohepatitis progressed with the MCD feeding period from 2 to 6weeks, but significant fibrosis was observed only in mice fed MCD for 6weeks. Gd-EOB-DTPA-enhanced MRI showed that Tmax was significantly prolonged in the livers of the 6-week group compared to the control group (control, 4.0±0.7min; MCD 6w, 12.1±1.6min), although there was no alteration in the 2- and 4-week groups. T1/2 was significantly prolonged in mice fed MCD for 4 and 6weeks compared to the control group (control, 19.9±2.0min; MCD 4w, 46.7±8.7min; MCD 6w, 65.4±8.8min). The parameters of Gd-EOB-DTPA kinetics (Tmax and T1/2) in the liver were positively correlated with the liver histopathological score (steatosis vs Tmax, rho=0.69, P=0.0007; inflammation vs Tmax, rho=0.66, P=0.00155; steatosis vs T1/2, rho=0.77, Pmouse model of NASH, suggesting the possibility of detecting the steatohepatitis stage without fibrosis by Gd-EOB-DTPA-enhanced MR imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Type gaucher disease: radiographic and MRI manifestations

    International Nuclear Information System (INIS)

    Dong Yanqing; Li Kuncheng; Wang Yunzhao; Tian Ding

    1999-01-01

    Objective: To enhance the understanding of Gaucher disease (GD) type I bone involvement on imaging findings. Methods: The X-ray plain film and MRI findings of GD type I were reported, and literature reviewed. Results: The X-ray plain film of GD had characteristic change. The extent of bone involvement demonstrated could be depicted in longitudinal direction and the changes of marrow involvement on MRI. Conclusions: MRI is the best way to diagnose the bone involvement of GD

  20. Quantitative evaluation of liver function with MRI using Gd-EOB-DTPA

    International Nuclear Information System (INIS)

    Ryeom, Hun Kyu; Kim, Seong Hun; Kim, Jong Yeol; Kim, Hye Jeong; Lee, Jong Min; Chang, Yong Min; Kim, Yong Sun; Kang, Duk Sik

    2004-01-01

    Gadolinium ethoxybenzoyl diethylenetriaminepentaacetic acid Gd-EOB-DTPA) is a newly developed MR contrast agent. After intravenous injection Gd-EOB-DTPA is gradually taken up by the hepatocytes and eventually excreed via the biliary pathway without any change to its chemical structure. Because of these characteristics, it can be used as a tracer for quantitative liver function testing. The purpose of this study is to develop a noninvasive method of quantitation of the hepatic function using Gd-EOB-DTPA through the deconvolution analysis. Adult New Zealand white rabbits (n = 10, average body weight = 3.5 kg) were used in the present study. Hepatic injury was induced to by the intragastric administration of carbon tetrachloride (CCI4) three times a week for three weeks. Liver enzyme (aspartate aminotransferase, AST; alanine aminotransferase, ALT) levels and the plasma indocyanine green (ICG) retention rate 15 minutes after an intravenous injection of ICG (ICG R15), was checked before and after the three-week administration of CCI4. At the end of experimental period, an observer 'blinded' to the treatment given the rabbits performed the histological examination. MRI studies were performed before and after the three-week administration of CCI4 on a 1.5 T scanner using a human extremity coil. After intravenous bolus injection of Gd-EOB-DTPA (0.3 mL if Gd-EOB-DTPA freshly prepared in 2.7 mL of normal saline) through the ear vein, the 250 axial single level dynamic MR images were obtained using a fast low angle shot (FLASH, TR/TE = 11/4.2 msec, flip angle = 15, acquisition time 1 second, slice thickness = 5 mm, matrix = 128 x 128, field of view = 120 mm) sequence with 1.5 sec time intervals. The time-intensity curves were obtained at the abdominal aorta and the liver parenchyma that was devoid of blood vessels. Deconvolution analysis of the aortic (input function) and hepatic parenchymal (output function) time-intensity curves was performed with a modified Fourier

  1. Real-time tracking of dissociation of hyperpolarized 89Y-DTPA: a model for degradation of open-chain Gd3+ MRI contrast agents

    Science.gov (United States)

    Ferguson, Sarah; Niedbalski, Peter; Parish, Christopher; Kiswandhi, Andhika; Kovacs, Zoltan; Lumata, Lloyd

    Gadolinium (Gd) complexes are widely used relaxation-based clinical contrast agents in magnetic resonance imaging (MRI). Gd-based MRI contrast agents with open-chain ligand such as Gd-DTPA, commercially known as magnevist, are less stable compared to Gd complexes with macrocyclic ligands such as GdDOTA (Dotarem). The dissociation of Gd-DPTA into Gd ion and DTPA ligand under certain biological conditions such as high zinc levels can potentially cause kidney damage. Since Gd is paramagnetic, direct NMR detection of the Gd-DTPA dissociation is quite challenging due to ultra-short relaxation times. In this work, we have investigated Y-DTPA as a model for Gd-DPTA dissociation under high zinc content solutions. Using dissolution dynamic nuclear polarization (DNP), the 89Y NMR signal is amplified by several thousand-fold. Due to the the relatively long T1 relaxation time of 89Y which translates to hyperpolarization lifetime of several minutes, the dissociation of Y-DTPA can be tracked in real-time by hyperpolarized 89Y NMR spectroscopy. Dissociation kinetic rates and implications on the degradation of open-chain Gd3+ MRI contrast agents will be discussed. This work was supported by the U.S. Department of Defense Award Number W81XWH-14-1-0048 and by the Robert A. Welch Foundation research Grant Number AT-1877.

  2. Basivertebral plexus enhancement at MR imaging after Gd-DTPA administration

    International Nuclear Information System (INIS)

    Bronstein, A.D.; Cohen, W.A.; Maravilla, K.R.

    1989-01-01

    This paper presents a study to identify noncontrast versus post-Gd-DTPA MR images of the spine, we analyzed the basivertebral plexus. The authors postulate that there are consistent patterns of enhancement specific with Gd-DTPA. This is a retrospective examination of the normal appearance and enhancement patterns of the basivertebral plexus in 805 vertebrae of 30 patients who underwent pre- and post-Gd-DTPA T1-weighted sagittal MR imaging of the spine. All patients show enhancement of the basivertebral plexus in a significant number of vertebrae when pre-and postcontrast images are compared

  3. Role of Gd-DTPA enhanced fat-suppression MR imaging on ovarian tumors

    International Nuclear Information System (INIS)

    Kang, Heoung Keun; Moon, Woong Jae; Seo, Jeong Jin; Kim, Jae Kyu; Park, Jin Gyoon; Choi, Ho Sun

    1995-01-01

    To determine the value of Gd-DTPA enhanced fat-suppression (GEFS) MR imaging in the characterization and differentiation of benign from malignant ovarian tumors. MRI findings of thirty-seven patients with surgically proved 44 ovarian tumors (30 benign, 14 malignant) were studied retrospectively. MR imaging with conventional spin echo (CSE; T1-weighted image TR/TE 450/20, T2-weighted image TR/TE 3500/30, 90) and GEFS were performed with a 1.5T GE signa. MRI findings of tumors including cystic or solid, wall and septal thickness, necrosis, invasion to adjacent organ, ascites and lymphadenopathy were assessed separately by using CSE and GEFS images, and then tumors were characterized as benign or malignant. Compared with CSE image, GEFS MR image showed better visualization of solid component in 5 malignant lesions, wall thickness in 5 malignant and 1 benign lesions, septal thickness in 3 malignant and 1 benign lesions, necrosis in 1 malignant lesion, and adjacent soft tissue invasion in 5 malignant lesions. Correct characterization of malignant tumors was increased from 71% on CSE image to 93% on GEFS image. However, correct characterization of benign tumors was 93% on both images. GEFS MR imaging could be useful for characterization of ovarian tumors, especially in malignant cases, and employed for differentiation of benign from malignant tumors

  4. Gd-DTPA-enhanced lesions in the brain of patients with acute optic neuritis

    DEFF Research Database (Denmark)

    Christiansen, P; Frederiksen, J L; Henriksen, O

    1992-01-01

    The cerebral hemispheres of 19 patients with acute monosymptomatic optic neuritis (AMON) were investigated using magnetic resonance imaging (MRI) and Gadolinium-DTPA (Gd-DTPA). Using T1-weighted and T2-weighted imaging sequences it was disclosed that 14 of 19 patients had lesions...

  5. Surface Modification of Gd Nanoparticles with pH-Responsive Block Copolymers for Use As Smart MRI Contrast Agents.

    Science.gov (United States)

    Zhu, Liping; Yang, Yuan; Farquhar, Kirsten; Wang, Jingjing; Tian, Chixia; Ranville, James; Boyes, Stephen G

    2016-02-01

    Despite recent advances in the understanding of fundamental cancer biology, cancer remains the second most common cause of death in the United States. One of the primary factors indicative of high cancer morbidity and mortality and aggressive cancer phenotypes is tumors with a low extracellular pH (pHe). Thus, the ability to measure tumor pHe in vivo using noninvasive and accurate techniques that also provide high spatiotemporal resolution has become increasingly important and is of great interest to researchers and clinicians. In an effort to develop a pH-responsive magnetic resonance imaging (MRI) contrast agent (CA) that has the potential to be used to measure tumor pHe, well-defined pH-responsive polymers, synthesized via reversible addition-fragmentation chain transfer polymerization, were attached to the surface of gadolinium-based nanoparticles (GdNPs) via a "grafting to" method after reduction of the thiocarbonylthio end groups. The successful modification of the GdNPs was verified by transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and dynamic light scattering. The performance of the pH-responsive polymer modified GdNPs was then evaluated for potential use as smart MRI CAs via monitoring the relaxivity changes with changing environmental pH. The results suggested that the pH-responsive polymers can be used to effectively modify the GdNPs surface to prepare a smart contrast agent for MRI.

  6. MR enhancement of epidural fibrosis by Gd-DTPA: Biodistribution and mechanism

    International Nuclear Information System (INIS)

    Ross, J.S.; Delamater, R.; Van Dyke, C.W.; Masaryk, T.J.; Hueftle, M.G.; Bohlman, H.; Modic, M.T.

    1987-01-01

    Epidural lumbar fibrosis was induced in eight beagle dogs at the L-6 level. Vascular injection with india ink showed abundant vessels in the scar. This agreed with light microscopy in eight patients with epidural fibrosis, which enhanced with Gd-DTPA from a clinical trial. Electron microscopy of epidural scar in humans and dogs demonstrated a continuous endothelium with scattered tight junctions. Biodistirbution was determined in four dogs with rapid MR scanning following intravenous (IV) bolus of 0.1 mmol/kg of Gd-DTPA and radioassay of tissue samples following Gd-153-DTPA IV injection. Maximum percent enhancement (70% humans, 100% dogs) occurred at 3-6 minutes in epidural fibrosis with a slow decline in enhancement over the next hour. These findings suggest that Gd-DTPA enhancement of epidural fibrosis is via an extracellular distribution within vascularized scar tissue

  7. Absolute renal blood flow quantification by dynamic MRI and Gd-DTPA

    International Nuclear Information System (INIS)

    Vallee, J.P.; Lazeyras, F.; Khan, H.G.; Terrier, F.

    2000-01-01

    The aim of this study was to demonstrate the feasibility of the absolute renal blood flow quantification using MRI and injection of contrast media. Using a T1-weighted fast gradient sequence following an intravenous bolus injection of Gd-DTPA, dynamic images of the kidney were obtained in patients with well-functioning native kidneys (n=7) or transplant (n=9), with significant renal artery stenosis (n=4) and with renal failure (n=7). After signal intensity calibration, the absolute renal perfusion was equal to the wash-in slope of the renal transit curve divided by the contrast medium concentration at the peak of the bolus in the aorta. The cortical blood flow was 2.54±1.16 ml/min per gram in well-functioning kidneys decreasing to 1.09±0.75 ml/min per gram in case of renal artery stenosis (p=0.04) and to 0.51 ± 0.34 ml/min per gram in case of renal failure (p<0.001). These measurements were in agreement with previous results obtained by other methods. A standard MRI imaging sequence and a simple model can provide realistic quantitative data on renal perfusion. This work justifies further studies to compare this model with a gold standard for renal blood flow measurements. (orig.)

  8. Meningeal enhancement on MRI after craniotomy

    International Nuclear Information System (INIS)

    Nomura, Motohiro; Hasegawa, Mitsuhiro; Yamashima, Tetsumori; Yamashita, Junkoh; Suzuki, Masayuki

    1991-01-01

    Gd-DPTA-enhanced MR images in 94 patients who had undergone craniotomy were studied, with particular attention paid to the meningeal enhancement. Such enhancement was noted in 26 of the 94 (27.6%) in the portion surrounding the craniotomy site. Meningeal enhancement, presumably of the subdural neomembrane, was apparent as a third line of a high signal intensity on T 1 -weighted MR images. The outer two high-intensity lines were derived from fat in the subcutaneous tissues of the scalp and fat in the bone marrow of the calvaria. We designated this characteristic enhancement as a 'triple white line'. Of the 26 patients with meningeal enhancement, 22 cases (23.4%) showed such a 'triple white line', 11 cases (11.7%) showed falx enhancement, and 12 cases (12.8%) showed tentorial enhancement. The intervals between surgery and the appearance of the meningeal enhancement ranged from 4 days to 88 weeks. A small amount of bleeding into the dura-arachnoid interface induced by surgery might result in the subdural neomembrane, as has previously been reported. This neomembrane might be enhanced by the leakage of Gd-DTPA through the proliferating capillaries. As meningeal enhancement occurs in approximately a third of the cases following craniotomy, much care should be taken in the differential diagnosis of the infection, inflammation, and metastasis or dissemination of malignant brain tumors. (author)

  9. Measuring SPIO and Gd contrast agent magnetization using 3 T MRI

    Science.gov (United States)

    Cantillon-Murphy, Pádraig; Wald, Lawrence L.; Zahn, Markus; Adalsteinsson, Elfar

    2011-01-01

    Traditional methods of measuring magnetization in magnetic fluid samples, such as vibrating sample magnetometry (VSM), are typically limited to maximum field strengths of about 1 T. This work demonstrates the ability of MRI to measure the magnetization associated with two commercial MRI contrast agents at 3 T by comparing analytical solutions to experimental imaging results for the field pattern associated with agents in cylindrical vials. The results of the VSM and fitted MRI data match closely. The method represents an improvement over VSM measurements since results are attainable at imaging field strengths. The agents investigated are Feridex, a superparamagnetic iron oxide suspension used primarily for liver imaging, and Magnevist, a paramagnetic, gadolinium-based compound used for tumors, inflammation and vascular lesions. MR imaging of the agents took place in sealed cylindrical vials in the presence of a surrounding volume of deionized water where the effects of the contrast agents had a measurable effect on the water's magnetization in the vicinity of the compartment of contrast agent. A pair of phase images were used to reconstruct a B0 fieldmap. The resultant B0 maps in the water region, corrected for shimming and container edge effects, were used to predict the agent's magnetization at 3 T. The results were compared with the results from VSM measurements up to 1.2 T and close correlation was observed. The technique should be of interest to those seeking quantification of the magnetization associated with magnetic suspensions beyond the traditional scope of VSM. The magnetization needs to be sufficiently strong (Ms≳50 Am2/kg Fe for Feridex and χm≳5 × 10−5 m3/kg Gd for Magnevist) for a measurable dipole field in the surrounding water. For this reason, the technique is mostly suitable for undiluted agents. PMID:19588450

  10. Optimizing the Relaxivity of MRI Probes at High Magnetic Field Strengths With Binuclear GdIII Complexes

    Directory of Open Access Journals (Sweden)

    Loredana Leone

    2018-05-01

    Full Text Available The key criteria to optimize the relaxivity of a Gd(III contrast agent at high fields (defined as the region ≥ 1.5 T can be summarized as follows: (i the occurrence of a rotational correlation time τR in the range of ca. 0.2–0.5 ns; (ii the rate of water exchange is not critical, but a τM < 100 ns is preferred; (iii a relevant contribution from water molecules in the second sphere of hydration. In addition, the use of macrocycle-based systems ensures the formation of thermodynamically and kinetically stable Gd(III complexes. Binuclear Gd(III complexes could potentially meet these requirements. Their efficiency depends primarily on the degree of flexibility of the linker connecting the two monomeric units, the absence of local motions and the presence of contribution from the second sphere water molecules. With the aim to maximize relaxivity (per Gd over a wide range of magnetic field strengths, two binuclear Gd(III chelates derived from the well-known macrocyclic systems DOTA-monopropionamide and HPDO3A (Gd2L1 and Gd2L2, respectively were synthesized through a multistep synthesis. Chemical Exchange Saturation Transfer (CEST experiments carried out on Eu2L2 at different pH showed the occurrence of a CEST effect at acidic pH that disappears at neutral pH, associated with the deprotonation of the hydroxyl groups. Then, a complete 1H and 17O NMR relaxometric study was carried out in order to evaluate the parameters that govern the relaxivity associated with these complexes. The relaxivities of Gd2L1 and Gd2L2 (20 MHz, 298 K are 8.7 and 9.5 mM−1 s−1, respectively, +77% and +106% higher than the relaxivity values of the corresponding mononuclear GdDOTAMAP-En and GdHPDO3A complexes. A significant contribution of second sphere water molecules was accounted for the strong relaxivity enhancement of Gd2L2. MR phantom images of the dinuclear complexes compared to GdHPDO3A, recorded at 7 T, confirmed the superiority of Gd2L2. Finally, ab initio

  11. Renal enhancement and excretion of the hepatobiliary contrast agent Gd-EOB-DTPA

    International Nuclear Information System (INIS)

    Zangos, S.; Hammerstingl, R.; Mack, M.G.; Straub, R.; Engelmann, K.; Eichler, K.; Vogl, T.J.

    2001-01-01

    Purpose: To evaluate the clinical value of the renal clearance using MR imaging with different doses of gadolinium ethoxybenzyl-DTPA (Gd-EOB-DTPA) in comparison to gadolinium DTPA (Gd-DTPA). Material and Methods: In a double-blind and randomized clinical phase II study. MR imaging at 1.5 T was performed in 61 patients with five different doses of Gd-EOB-DTPA (3, 6, 12.5, 25 and 50 μmol/kg b.w. as a bolus injection). The study protocol comprised T 1 - and T 2 -weighted spin-echo magnetic resonance and two-dimensional fast low-angle shot imaging before and at increasing intervals for up to 45 min after injection of Gd-EOB-DTPA. These images were compared with Gd-DTPA-enhanced imaging (0.1 mmol/kg b. w. as a bolus injection). Results: After bolus injection of the hepatobiliary MR contrast agent Gd-EOB-DTPA a renal elimination was observed. Immediately after the injection of Gd-EOB-DTPA until the eighth minute a corticomedullary enhancement of the kidney was conspicuous. After the fourth minute a contrast enhancement could be seen in the renal pelvis. The best enhancement was noted after 20 minutes in the FLASH GRE and T 1 -weighted images with good pelvicaliceal contrast. After 45 minutes an outflow of Gd-EOB-DTPA into the ureter could be observed. Conclusion: In addition to the hepatobiliary secretion Gd-EOB-DTPA appears useful for the evaluation of renal structures and renal function on account of the renal excretion without diuretic preparation of the patients. (orig.) [de

  12. Study for synovial lesions by MRI using gadolinium-DTPA (Gd-DTPA) in patients with early phase of rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Keiyu (Saint Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine)

    1993-02-01

    To evaluate the usefulness of magnetic resonanse imaging (MRI) enhanced with gadolinium-DTPA (Gd-DTPA) for the detection of the inflamed synovium and for the evaluation of the responce to therapy in rheumatoid arthritis, we studied 49 patients with rheumatoid arthritis (RA) according to the 1987 revised criteria of American Rheumatism Association (ARA), 6 patients with systemic lupus erythematosus (SLE) complicated by arthritis, 3 patients with osteoarthritis (OA), 2 patients with Sjoegren syndrome, 2 patients with progressive systemic sclerosis and 10 healthy volunteers as an age matched control. The 49 patients with RA were divided into three groups: (1) early phase of RA, (2) non progressing RA and (3) slowly progressing RA, and the stage classification of plain X-ray film and enhancement pattern of MR imaging were classified into three groups. Synovial enhancement showed a linear, band-like or diffuse pattern. Almost all cases in early phase of RA group and non progressing RA group showed a linear pattern, a band-like pattern or even no enhancement, while slowly progressing group of stage II or higher showed the diffuse pattern of enhancement in all except 2 cases. Moreover, the linear pattern, the band-like pattern or even no contrast enhancement were seen in all except 1 stage I patient, whereas 26 out of 29 patients with stage II or higher change showed diffuse contrast enhancement. Furthermore, a comparison of MR images before and after administration of disease modifying antirheumatic drugs (DMARDs) in 10 patients showed that the improvement of clinical symptomes correlated fairly well with reduction of contrast enhancement. The present study suggested that MRI of the wrist using Gd-DTPA enhancement may be useful for the diagnosis of RA, the prediction of articular damage, and judgement of the response to therapy. (author).

  13. MRI-CEST assessment of tumour perfusion using X-ray iodinated agents: comparison with a conventional Gd-based agent

    Energy Technology Data Exchange (ETDEWEB)

    Anemone, Annasofia; Consolino, Lorena [Universita degli Studi di Torino, Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Torino (Italy); Longo, Dario Livio [Universita degli Studi di Torino, Istituto di Biostrutture e Bioimmagini (CNR) c/o Centro di Biotecnologie Molecolari, Torino (Italy)

    2017-05-15

    X-ray iodinated contrast media have been shown to generate contrast in MR images when used with the chemical exchange saturation transfer (CEST) approach. The aim of this study is to compare contrast enhancement (CE) capabilities and perfusion estimates between radiographic molecules and a Gd-based contrast agent in two tumour murine models with different vascularization patterns. MRI-CEST and MRI-CE T{sub 1w} images were acquired in murine TS/A and 4 T1 breast tumours upon sequential i.v. injection of iodinated contrast media (iodixanol, iohexol, and iopamidol) and of gadoteridol. The signal enhancements observed in the two acquisition modalities were evaluated using Pearson's correlation, and the correspondence in the spatial distribution was assessed by a voxelwise comparison. A significant, positive correlation was observed between iodinated contrast media and gadoteridol for tumour contrast enhancement and perfusion values for both tumour models (r = 0.51-0.62). High spatial correlations were observed in perfusion maps between iodinated molecules and gadoteridol (r = 0.68-0.86). Tumour parametric maps derived by iodinated contrast media and gadoteridol showed high spatial similarities. A good to strong spatial correlation between tumour perfusion parameters derived from MRI-CEST and MRI-CE modalities indicates that the two procedures provide similar information. (orig.)

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

    Science.gov (United States)

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

    2010-11-01

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

  15. Gd-enhanced MR imaging of the herniated lumbar disc: patterns of enhancement

    International Nuclear Information System (INIS)

    Kwag, Hyon Joo; Choi, Hye Young; Kim, Hyae Young; Kim, Yoo Kyung; Kim, Ah Young; Chung, Eun Chul

    1995-01-01

    The purpose of this study is to describe the patterns of enhancement of the herniated lumbar disc with Gd-DTPA enhanced MR imaging. Out of 65 patients, 103 lumbar discs diagnosed to be herniated by MR image were retrospectively analyzed. The MR imaging was performed with 1.5 T MR unit, using T1-and T2-weighted sagittal and axial spin echo techniques. Contrast-enhanced T1 weighted sagittal and axial images were performed after intravenous injection of Gadopentetate-dimeglumine(Magnevist, Shering) (0.1 mmol/kg). Contrast enhancement was seen in 66 cases(64%). Thirteen cases of bulging disc were not enhanced. Twenty-eight cases of protruded disc showed intraannular enchantment in 23 cases, peripheral linear and irregular enhancement in each of one case, and nonenhancement in three cases. Fifty-seven cases of extruded disc showed irregular enhancement in 14 cases, peripheral linear enhancement in 12 cases, peripheral ring enhancement in five cases and intraannular enhancement in five cases. All five cases of sequestered disc showed peripheral ring enhancement. Protruded discs show intraannular enhancement frequently and sequestered discs usually show peripheral ring enhancement. Enhanced MR imaging may be helpful to evaluate the type of herniated lumbar disc and relationship among disc material, nerve root and thecal sac

  16. Experimental evaluation of contrast-enhanced high-reselution MR angiography in the rabbit. Gd-DTPA versus Gd-DTPA polylysin

    International Nuclear Information System (INIS)

    Vogl, T.J.; Hoffmann, Y.; Juergens, M.; Weinmann, H.J.; Muehler, A.; Yucel, S.; Felix, R.

    1996-01-01

    In ten anesthesized rabbits (average weight 4.3 kg) MR angiography was performed using a 1.5 TMR unit (Magnetom SP63; Siemens Erlangen) and a CP head coil. Arterial MRA (FISP 3D TONE, TR/TE=33/8, Flip 20 ) and venous MRA (FLASH 2D, TR/TE=37/10, Flip 60 ) was performed before and after administration of the paramagnetic contrast agents Gd-DTPA (n=5) or Gd-DTPA polylysine (n=5) at a doseage of 0.1 mmol/kg. In all studies the single selections and the MIP reconstructions were evaluated quantitatively by measuring and calculating signal intensity, percentage enhancement, signal-to-noise and contrast-to-noise ratios. All studies were assessed qualitatively for visualization and distinction of the arterial and venous vessel system by three independent observers before and after the administration of contrast agent. Results: Gd-DTPA-enhanced arterial FISP 3D tone led to a percentage enhancement of 30% for the kidneys, 12% for the superior mesenteric artery, 18% for the deep circumfluent iliac artery, and 7% for the internal iliac artery. In FLASH 2D sequences Gd-DTPA led to a good C/N only for venous abdominal vessels like the left renal vein (2.59) and internal iliac vein (1.66); the percentage enhancement of these structures was between 16 and 21%. Qualitative comparison also showed no significant improvement after injection of Gd-DTPA. In FISP 3D TONE sequences Gd-DTPA polylysine led to a strong percentlage enhancement of right and left kidney (21 and 40%) and deep circumfluent iliac artery (17%). Qualitative evaluation showed improved delineation and contrast of low-diameter vessels, while the soft tissue was only slightly enhanced and did not impair vessel visualization. Conclusion: CMRA using Gd-DTPA and Gd-DTPA polylysine significantly improved the delineation of abdominal vessels, with Gd-DTPA polylysine being superior. (orig.) [de

  17. Pathophysiological study of chronic subdural hematoma and communicating hydrocephalus with delayed MRI using Gd-DTPA (Magnevist)

    Energy Technology Data Exchange (ETDEWEB)

    Shinoura, Nobusada; Kondo, Tatsuya; Yamakawa, Kenta; Makiuchi, Tsuneo; Fujii, Kyoichi; Yoshioka, Masumi (National Medical Center of Hospital, Tokyo (Japan))

    1991-06-01

    Concerning the pathophysiology of chronic subdural hematoma and communicating hydrocephalus, recent studies have been made, but no definitive conclusion has yet been attained. To study their complicated mechanisms, we examined a delayed MRI which was performed 4 hours after the intravenous injection of Gd-diethylenetriaminepentaacetic acid (Gd-DTPA) on 5 cases of subdural hygroma, 3 cases of chronic subdural hematoma after irrigation, one case of hydrocephalus with glioblastoma, and one case of Parkinson syndrome. In every case of subdural hygroma, it was certified that Gd-DTPA was leaked into the cavity of the subdural space. This is perhaps because the outer and inner membranes of the subdural hygroma consist of fibroblasts and of capillary vessels with fenestration; the leakage of blood composition through this fenestration may promote the growth of the membrane and the cavity. The leakage of Gd-DTPA decreased after irrigation, and it did not recur. In the case of hydrocephalus with gioblastoma, there was leakage of Gd-DTPA into the ventricles surrounding the tumor. This may be because of the destruction of the blood-cerebrospinal fluid barrier; perhaps this is associated with the cause of the communicating hydrocephalus. (author).

  18. Pathophysiological study of chronic subdural hematoma and communicating hydrocephalus with delayed MRI using Gd-DTPA (Magnevist)

    International Nuclear Information System (INIS)

    Shinoura, Nobusada; Kondo, Tatsuya; Yamakawa, Kenta; Makiuchi, Tsuneo; Fujii, Kyoichi; Yoshioka, Masumi

    1991-01-01

    Concerning the pathophysiology of chronic subdural hematoma and communicating hydrocephalus, recent studies have been made, but no definitive conclusion has yet been attained. To study their complicated mechanisms, we examined a delayed MRI which was performed 4 hours after the intravenous injection of Gd-diethylenetriaminepentaacetic acid (Gd-DTPA) on 5 cases of subdural hygroma, 3 cases of chronic subdural hematoma after irrigation, one case of hydrocephalus with glioblastoma, and one case of Parkinson syndrome. In every case of subdural hygroma, it was certified that Gd-DTPA was leaked into the cavity of the subdural space. This is perhaps because the outer and inner membranes of the subdural hygroma consist of fibroblasts and of capillary vessels with fenestration; the leakage of blood composition through this fenestration may promote the growth of the membrane and the cavity. The leakage of Gd-DTPA decreased after irrigation, and it did not recur. In the case of hydrocephalus with gioblastoma, there was leakage of Gd-DTPA into the ventricles surrounding the tumor. This may be because of the destruction of the blood-cerebrospinal fluid barrier; perhaps this is associated with the cause of the communicating hydrocephalus. (author)

  19. Synthesis and Characterization of a Gd-DOTA-D-Permeation Peptide for Magnetic Resonance Relaxation Enhancement of Intracellular Targets

    Directory of Open Access Journals (Sweden)

    Andrew M. Prantner

    2003-10-01

    Full Text Available Many MR contrast agents have been developed and proven effective for extracellular nontargeted applications, but exploitation of intracellular MR contrast agents has been elusive due to the permeability barrier of the plasma membrane. Peptide transduction domains can circumvent this permeability barrier and deliver cargo molecules to the cell interior. Based upon enhanced cellular uptake of permeation peptides with D-amino acid residues, an all-D Tat basic domain peptide was conjugated to DOTA and chelated to gadolinium. Gd-DOTA-D-Tat peptide in serum at room temperature showed a relaxivity of 7.94 ± 0.11 mM−1 sec−1 at 4.7 T. The peptide complex displayed no significant binding to serum proteins, was efficiently internalized by human Jurkat leukemia cells resulting in intracellular T1 relaxation enhancement, and in preliminary T1-weighted MRI experiments, significantly enhanced liver, kidney, and mesenteric signals.

  20. Volume Change and Liver Parenchymal Signal Intensity in Gd-EOB-DTPA-Enhanced Magnetic Resonance Imaging after Portal Vein Embolization prior to Hepatectomy

    Directory of Open Access Journals (Sweden)

    Ayako Akiba

    2014-01-01

    Full Text Available Purpose. To investigate the liver volume change and the potential of early evaluation by contrast-enhanced magnetic resonance imaging (MRI using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA after portal vein embolization (PVE. Materials and Methods. Retrospective evaluations of computed tomography (CT volumetry of total liver and nonembolized areas were performed before and 3 weeks after PVE in 37 cases. The percentage of future liver remnant (%FLR and the change ratio of %FLR (%FLR ratio were calculated. Prospective evaluation of signal intensities (SIs was performed to estimate the role of Gd-EOB-DTPA-enhanced MRI as a predictor of hypertrophy in 16 cases. The SI contrast between embolized and nonembolized areas was calculated 1 week after PVE. The change in SI contrast before and after PVE (SI ratio was also calculated in 11 cases. Results. %FLR ratio significantly increased, and SI ratio significantly decreased (both P<0.01. There were significant negative correlations between %FLR and SI contrast and between %FLR and SI ratio (both P<0.01. Conclusion. Hypertrophy in the nonembolized area after PVE was indicated by CT volumetry, and measurement of SI contrast and SI ratio in Gd-EOB-DTPA-enhanced MRI early after PVE may be useful to predict the potential for hepatic hypertrophy.

  1. Detectability of hepatocellular carcinoma: comparison of Gd-DTPA-enhanced and SPIO-enhanced MR imaging

    International Nuclear Information System (INIS)

    Kwak, Hyo Sung; Lee, Jeong Min; Kim In Hwan; Kim, Chong Soo; Han, Hyeun Young; Yoon, Kwon ha; Shin, Kyung Sook

    2000-01-01

    To compare the detectability of hepatocellular carcinoma (HCC) using superparamagnetic iron oxide (SPIO)-enhanced T2-weighted turbo spin echo (TSE), SPIO-enhanced T2-weighted FISP, and dynamic Gd-DTPA-enhanced fast low-angle shot (FLASH) MR images. In order to assess their hepatic lesions, 25 patients (20 men and 5 women) with HCC were enrolled in an MR study in which both gadolinium and Spiro were used. Since the lesions were most conspicuous during the phase of dynamic arterial dominant phase of dynamic gadolinium-enhanced imaging, this was the phase used for analysis. Images were analyzed qualitatively and quantitatively, and to compare the diagnostic value of gadolinium-enhanced imaging with that of SPIO-enhanced imaging for the detection of HCCs, a receiver-operated characteristic curve was obtained. Qualitative analysis revealed a significantly higher percentage of signal loss and a higher liver-lesion contrast-to-noise ratio on SPIO-enhanced FISP imaging than on SPIO-enhanced T2-weighted TSE imaging (p less than 0.05). It also showed that the lesions were most clearly visible on SPIO-enhanced FISP imaging (and significantly so), followed by SPIO-enhanced T2-weighted TSE imaging, and dynamic gadolinium-enhanced imaging. Imaging artifacts were more prominent on SPIO-enhanced T2-weighted TSE than on SPIO-enhanced PISF imaging or dynamic gadolinium-enhanced imaging (p less than 0.05). According to ROC analysis, SPIO-enhanced T2-weighted turbo spin echo (TSE) or SPIO-enhanced FISP imaging achieved higher accuracy than did dynamic gadolinium-enhanced FLASH imaging (p less than 0.05). For the detection of hepatocellular carcinomas, SPIO-enhanced MR imaging is better than gadolinium-enhanced FLASH imaging

  2. Labyrinthine enhancement of Gd-MR in patients with sudden hearing loss and vertigo

    International Nuclear Information System (INIS)

    Seltzer, S.; Mark, A.S.; Chapman, J.C.; Nelson-Drake, J.

    1989-01-01

    In the past, no definitive diagnostic study was available to assess causes of sudden-onset hearing loss and vertigo. Our observations have led to an interesting new finding: labyrinthine enhancement on Gd-enhanced MR imaging in four patients with sudden unilateral hearing loss and/or vertigo. MR findings were correlated with audiologic and vestibular studies. All patients were studied with T2-weighted axial images through the whole brain and with Gd-DTPA-enhanced, 3-mm, axial, T1-weighted images through the temporal bone. No labyrinthine enhancement was seen in 20 control patients referred for other clinical problems. Gd-MR imaging might be able to distinguish patients with retrocochlear lesions from those in whom the abnormal process is in the labyrinth or is intraaxial

  3. Facile Synthesis of Gd-Functionalized Gold Nanoclusters as Potential MRI/CT Contrast Agents

    Directory of Open Access Journals (Sweden)

    Wenjun Le

    2016-04-01

    Full Text Available Multi-modal imaging plays a key role in the earlier detection of disease. In this work, a facile bioinspired method was developed to synthesize Gd-functionalized gold nanoclusters (Gd-Au NCs. The Gd-Au NCs exhibit a uniform size, with an average size of 5.6 nm in dynamic light scattering (DLS, which is a bit bigger than gold clusters (3.74 nm, DLS, while the fluorescent properties of Gd-Au NCs are almost the same as that of Au NCs. Moreover, the Gd-Au NCs exhibit a high longitudinal relaxivity value (r1 of 22.111 s−1 per mM of Gd in phosphate-buffered saline (PBS, which is six times higher than that of commercial Magnevist (A complex of gadolinium with a chelating agent, diethylenetriamine penta-acetic acid, Gd-DTPA, r1 = 3.56 mM−1·s−1. Besides, as evaluated by nano single photon emission computed tomography (SPECT and computed tomography (CT the Gd-Au NCs have a potential application as CT contrast agents because of the Au element. Finally, the Gd-Au NCs show little cytotoxicity, even when the Au concentration is up to 250 μM. Thus, the Gd-Au NCs can act as multi-modal imaging contrast agents.

  4. Surface modification of PLGA nanospheres with Gd-DTPA and Gd-DOTA for high-relaxivity MRI contrast agents

    NARCIS (Netherlands)

    Ratzinger, Gerda; Agrawal, Prashant; Körner, Wilfried; Lonkai, Julia; Sanders, Honorius M. H. F.; Terreno, Enzo; Wirth, Michael; Strijkers, Gustav J.; Nicolay, Klaas; Gabor, Franz

    2010-01-01

    The preparation of particulate contrast agents for magnetic resonance imaging (MRI) based on biodegradable poly(D,L-lactide-co-glycolide) (PLGA) nanocarriers is reported. By spacer-aided covalent surface-grafting of the prominent chelating ligands diethylenetriaminepentaacetic acid (DTPA) and

  5. Surface modification of PLGA nanospheres with Gd-DTPA and Gd-DOTA for high-relaxivity MRI contrast agents

    NARCIS (Netherlands)

    Ratzinger, G.; Agrawal, P.; Koerner, W.; Lonkai, J.; Sanders, H.M.H.F.; Terreno, E.; Wirth, M.; Strijkers, G. J.; Nicolay, K.; Gabor, F.

    2010-01-01

    The preparation of particulate contrast agents for magnetic resonance imaging (MRI) based on biodegradable poly(d,l-lactide-co-glycolide) (PLGA) nanocarriers is reported. By spacer-aided covalent surface-grafting of the prominent chelating ligands diethylenetriaminepentaacetic acid (DTPA) and

  6. Gd-BOPTA-enhanced excretory MR urography without administration of diuretics; Gd-BOPTA-gestuetzte MR-Ausscheidungsurographie ohne Diuretikagabe

    Energy Technology Data Exchange (ETDEWEB)

    Allkemper, T.; Tombach, B.; Heindel, W. [Muenster Univ. (Germany). Inst. fuer Klinische Radiologie

    2001-02-01

    Purpose: To evaluate the feasibility and clinical utility of Gd-BOPTA enhanced excretory magnetic resonance urography without additional administration of diuretics in correlation with conventional urography. Method: 15 preoperative patients with pelvic tumors were examined at 1.5 T using a breath-hold high-resolution 3D-FLASH sequence during first-pass as well as 5, 10, 15 minutes after iv. injection of 0.05 mmol/kg BW Gd-BOPTA (MultiHance {sup trademark}) without administration of diuretics. Post-processed coronal and multiplanar MIP reconstructions were compared to conventional excretory urography with regard to morphologic accuracy, anatomic variability, filling defects, cause and level of obstruction or compression, tumor visibility, and time-effectiveness by two independent radiologists. Results: Visualization of the urinary tract by MRU was comparable to conventional excretory urography in 14 of 15 cases. Caliceal fornices were better delineated on conventional urographies, whereas MRU was considered superior in the assessment of the inferior ureter sections, the urinary bladder and obstructive tumors, whose extents could be clearly marked out. Examination times of both techniques were comparable. Conclusion: These first results show that non-diuretic Gd-BOPTA enhanced MRU is comparable to conventional excretory urography for the preoperative diagnosis of pelvic tumors. Further improvements of this technique seem possible by optimization of examination intervals and injection doses. (orig.) [German] Ziel: Abschaetzung der Durchfuehrbarkeit und des klinischen Nutzens der Gd-BOPTA-gestuetzten MR-Ausscheidungsurographie (MRU) ohne zusaetzliche Diuretikagabe im Vergleich zur konventionellen Ausscheidungsurographie. Methoden: 15 Patienten mit Beckentumoren wurden praeoperativ an einem 1.5 T-Ganzkoerpersystem mit Hilfe einer atemgehaltenen, hochaufloesenden 3D-FLASH-Sequenz unmittelbar nach intra-venoeser Applikation von 0,05 mmol/kg KG Gd-BOPTA (MultiHance {sup

  7. Background parenchymal enhancement in preoperative breast MRI.

    Science.gov (United States)

    Kohara, Satoko; Ishigaki, Satoko; Satake, Hiroko; Kawamura, Akiko; Kawai, Hisashi; Kikumori, Toyone; Naganawa, Shinji

    2015-08-01

    We aimed to assess the influence of background parenchymal enhancement (BPE) on surgical planning performed using preoperative MRI for breast cancer evaluation. Between January 2009 and December 2010, 91 newly diagnosed breast cancer patients (mean age, 55.5 years; range, 30-88 years) who underwent preoperative bilateral breast MRI followed by planned breast conservation therapy were retrospectively enrolled. MRI was performed to assess the tumor extent in addition to mammography and breast ultrasonography. BPE in the contralateral normal breast MRI at the early dynamic phase was visually classified as follows: minimal (n=49), mild (n=27), moderate (n=7), and marked (n=8). The correlations between the BPE grade and age, menopausal status, index tumor size, changes in surgical management based on MRI results, positive predictive value (PPV) of MRI, and surgical margins were assessed. Patients in the strong BPE groups were significantly younger (p=0.002) and generally premenopausal (p<0.001). Surgical treatment was not changed in 67 cases (73.6%), while extended excision and mastectomy were performed in 12 cases (13.2%), each based on additional lesions on MRI. Six of 79 (7.6%) patients who underwent breast conservation therapy had tumor-positive resection margins. In cases where surgical management was changed, the PPV for MRI-detected foci was high in the minimal (91.7%) and mild groups (66.7%), and 0% in the moderate and marked groups (p=0.002). Strong BPE causes false-positive MRI findings and may lead to overly extensive surgery, whereas MRI may be beneficial in select patients with weak BPE.

  8. Follow-up of acute myocardial infarction with Gd-DTPA-enhanced MR image

    International Nuclear Information System (INIS)

    Matheijssen, N.A.A.; Dijkman, P.; Rossum, A.C. van der; Laarse, A. van der; Voorthuisen, A. van; Bruschke, A.

    1990-01-01

    MR imaging with Gd-DTPA has been shown to be useful in the identification of acutely infarcted myocardium. The purpose of this paper is to assess the influence of Gd-DTPA on myocardial signal intensity (SI) at different intervals after acute myocardial infarction (SMI). The authors used Gd-DTPA-enhanced MR imaging to study 84 patients at different intervals after AMI. A total of 109 T1-weighted MR studies were performed with a Philips Gyroscan magnet (0.5T) before and 20 minutes after Gd-DTPA (0.15 mmol/kg given intravenously). Four groups were studied. Group 1 underwent MR imaging less than 1 week after AMI; group 2, 1-3 weeks; group 3, 3-6 weeks; and group 4, over 6 weeks after AMI

  9. Haemophilic arthropathy of the knee. Gd-DTPA enhanced MRT. Clinical and radiological correlation; Haemophile Arthropathie des Kniegelenkes. Gd-DTPA-verstaerkte MRT: klinische und roentgenologische Korrelation

    Energy Technology Data Exchange (ETDEWEB)

    Naegele, M. [Radiologische Universitaetsklinik, Bonn (Germany); Kunze, V. [Radiologische Universitaetsklinik, Bonn (Germany); Hamann, M. [Radiologische Universitaetsklinik, Bonn (Germany); Eickhoff, H. [Orthopaedische Klinik, Krankenhaus Troisdorf (Germany); Koch, W. [Orthopaedische Klinik, Krankenhaus Troisdorf (Germany); Oldenburg, J. [Inst. fuer Experimentelle Haematologie und Transfusionsmedizin, Bonn (Germany); Reiser, M. [Muenchen Univ. (Germany). Inst. fuer Radiologische Diagnostik; Steudel, A. [Radiologische Universitaetsklinik, Bonn (Germany)

    1994-02-01

    17 patients with hemophilic arthropathy of the knee joint were studied with static and dynamic MRT before and after i.v. bolus injection of Gadolinium-DTPA (0,1 mmol/kg body weight). After contrast enhancement, synovial proliferations exhibited an increase of signal intensity (SI) of FFE and SE images of 47.7% and 37.4% respectively, whereas muscle and fatty tissue, tendons, bone marrow and joint effusion revealed only minor increase in SI. The gradient of signal intensity (ratio SI/time) of pannus was 39,6% min. Gd-DTPA enhanced MRI studies delineate and quantify the synovial proliferations in hemophilic arthropathy. Dynamic studies in hemophilic arthropathy do not provide qualitative assessment of the inflammatory process. (orig.) [Deutsch] Es wurden 17 Patienten mit einer haemophilen Arthropathie der Kniegelenke mit der statischen und dynamischen MRT vor und nach i.v. Bolusgabe von Gadolinium-DTPA (0,1 mmol/kg KG) untersucht. Nach Kontrastmittelgabe konnte ein Anstieg der Signalintensitaet des Pannus von 37,4% auf SE- und von 47,7% auf FFE-Aufnahmen gemessen werden. Der Gradient des Signalintensitaetsanstieges (%/Zeit) lag fuer Pannus bei 39,6%/min. Die Kontrastmittelgabe steigerte die Abgrenzbarkeit des Pannus von Gelenkerguss und den Gelenkbinnenstrukturen. Begleitend durchgefuehrte klinische und roentgenologische Bewertungen des Schweregrades der Arthropathie korrelierten nicht mit dem Signalintensitaetsverhalten des Pannus nach Kontrastmittelgabe. (orig.)

  10. Gadodiamide injection for enhancement of MRI in the CNS. Applications, dose, field and time dependence

    Energy Technology Data Exchange (ETDEWEB)

    Aakeson, P

    1996-10-01

    Gadodiamide injection was comparable to Gd-DTPA with regard to both safety and diagnostic efficiency in the central nervous system. The contrast effect of Gd contrast agents is higher at 1.5 T than at 0.3 T both in phantoms and patients with a maximum ratio (signal lesion/signal grey matter) more than 50% higher at 1.5 T. To achieve high contrast effect, heavily T1-weighted images are important. Prolonging the TR from 400 ms to 600 ms reduced the ratio by 15-45% depending on concentration. The effective time window for imaging of BBB (Blood-Brain Barrier) damage is between 2-5 and 25-30 minutes after injection and several scans can be performed without loss of enhancement. To provide maximum detectability of BBB damage in patients, higher doses of Gd contrast media should be useful, especially at low field strengths, as the doses used clinically today do not utilize the maximum contrast effect. High-dose (0.3 mmol/kg b.w.) contrast enhanced MRI (0.3 T) with Gadodiamide injection allowed detection of significantly more and smaller metastases (i.e. BBB damage) than standard dose (0.1 mmol/kg b.w.) High dose contrast-enhanced MRI (0.3 T) did not increase the diagnostic information for the evaluation of patients with failed back surgery syndrome compared to standard dose MRI. 55 refs, 9 figs, 10 tabs.

  11. Gadodiamide injection for enhancement of MRI in the CNS. Applications, dose, field and time dependence

    International Nuclear Information System (INIS)

    Aakeson, P.

    1996-01-01

    Gadodiamide injection was comparable to Gd-DTPA with regard to both safety and diagnostic efficiency in the central nervous system. The contrast effect of Gd contrast agents is higher at 1.5 T than at 0.3 T both in phantoms and patients with a maximum ratio (signal lesion/signal grey matter) more than 50% higher at 1.5 T. To achieve high contrast effect, heavily T1-weighted images are important. Prolonging the TR from 400 ms to 600 ms reduced the ratio by 15-45% depending on concentration. The effective time window for imaging of BBB (Blood-Brain Barrier) damage is between 2-5 and 25-30 minutes after injection and several scans can be performed without loss of enhancement. To provide maximum detectability of BBB damage in patients, higher doses of Gd contrast media should be useful, especially at low field strengths, as the doses used clinically today do not utilize the maximum contrast effect. High-dose (0.3 mmol/kg b.w.) contrast enhanced MRI (0.3 T) with Gadodiamide injection allowed detection of significantly more and smaller metastases (i.e. BBB damage) than standard dose (0.1 mmol/kg b.w.) High dose contrast-enhanced MRI (0.3 T) did not increase the diagnostic information for the evaluation of patients with failed back surgery syndrome compared to standard dose MRI. 55 refs, 9 figs, 10 tabs

  12. Dynamic contrast-enhanced MRI examination of atherosclerotic plaques: an animal study using rabbit model

    International Nuclear Information System (INIS)

    Li Mingli; Sun Jie; Chang Xiaoyan; Jin Zhengyu

    2011-01-01

    Objective: The enhanced patterns of atherosclerotic plaque on dynamic contrast- enhanced MRI have not been well studied. The aim of this study was to explore the patterns of plaque enhancement and their underlying mechanism by using dynamic contrast-enhanced MRI (DCE-MRI). Methods: Atherosclerotic plaques were induced in the aorta of 12 New Zealand White rabbits by a combination of endothelial denudation and high-cholesterol diet. Ten to sixteen weeks after surgery, DCE- MRI was performed with a fast spin echo T 1 weighted sequence. Thirty-five phases of images were obtained at 71-second intervals. Gd-DTPA was injected coincident with the third scan via marginal ear vein. Specimens were harvested within 12 hours after imaging for HE staining and CD31 immunohistochemical staining which was used to highlight neo-vessels. Plaque enhancement patterns were studied and compared with histological findings. Signal intensity of each plaque section was normalized to pre-contrast signal intensity of psoas muscle, after which signal intensity versus time curve was drawn. Pearson correlation coefficient was used to reveal association between histological neo-vessel count and descriptive parameters derived from signal intensity versus time curve. Results: Plaques were significantly enhanced by Gd-DTPA. Enhancement patterns could be described as 'fast-in and slow-out'. Differences in patterns of enhancement were observed between tissues, with fibrous tissue enhanced more than lipid aggregation and leukocyte foci. Peak enhancement (1.05±0.30), initial slope (0.82±0.28) and area under the curve at early phase (4.97± 1.67) derived from signal intensity-time curve had significant correlations with neo-vessel count (117.7± 93.3) (r=0.553, 0.468, 0.554 respectively, P<0.05). Conclusions: The enhanced patterns of atherosclerotic plaque by Gd-DTPA were 'fast- in and slow-out'. Neovascularization, increased endothelial permeability and extracellular matrix may be the reasons for

  13. Dynamic Contrast-Enhanced Magnetic Resonance Imaging with Gd-EOB-DTPA for the Evaluation of Liver Fibrosis Induced by Carbon Tetrachloride in Rats.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available To investigate the utility of dynamic contrast-enhanced MRI (DCE-MRI with Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA for detecting liver fibrosis induced by carbon tetrachloride (CCl4 in rats.This study was approved by the institutional animal care and use committee. Liver fibrosis in rats was induced by intraperitoneal injection of 1 mL/kg 50% CCl4 twice a week for 4-13 weeks. Control rats were injected with saline. Liver fibrosis was graded using the Metaviar score: no fibrosis (F0, mild fibrosis (F1-F2 and advanced fibrosis (F3-F4. DCE-MRI with Gd-EOB-DTPA was performed for all rats. Ktrans, Kep, Ve and iAUC of the liver parenchyma were measured. Relative enhancement (RE value of the liver was calculated on T1-weighted images at 15, 20 and 25 min after Gd-EOB-DTPA administration.Thirty-five rats were included: no fibrosis (n=13, mild fibrosis (n=11 and advanced fibrosis (n=11. Ktrans and iAUC values were highest in advanced fibrosis group and lowest in no fibrosis group (P<0.05. The area under the receiver operating characteristic curve (AUROC for fibrosis (stages F1 and greater were 0.773 and 0.882 for Ktrans and iAUC, respectively. AUROC for advanced fibrosis were 0.835 and 0.867 for Ktrans and iAUC, respectively. Kep and RE values were not able to differentiate fibrosis stages (all P>0.05.Ktrans and iAUC obtained from DCE-MRI with Gd-EOB-DTPA are useful for the detection and staging of rat liver fibrosis induced by CCl4.

  14. Gd-DTPA-enhanced MR imaging of avascular necrosis of the hip

    International Nuclear Information System (INIS)

    Van de Berg, B.; Malghem, J.; Noel, H.; Maldague, B.

    1990-01-01

    This paper evaluates the interest of Gd-DTPA-enhanced MR imaging in the diagnosis of avascular necrosis (AVN) of the hip. MR imaging of 10 patients with various stages of AVN of the femoral head (14 abnormal hips) was performed (1.5-T Gyroscan). T1-weighted images before and after contrast injection and T2-weighted images were obtained in two planes. MR images were compared with pathologic findings in six femoral head specimens (total hip replacement). In the early stages of AVN (Mitchell classes A and B), a peripheral band of contrast-enhanced tissue appears on T1-weighted images after Gd-DTPA injection, mimicking the double line seen on T2-weighted images. In later stages (class C and D), the sequestrated segments, appearing hypointense on T1-weighted images, usually show a significant signal intensity enhancement after Gd-DTPA injection. The truly avascular areas may be limited to a band of thickened subchondral bone

  15. Chronological evaluation of liver enhancement in patients with chronic liver disease at Gd-EOB-DTPA-enhanced 3-T MR imaging. Does liver function correlate with enhancement?

    International Nuclear Information System (INIS)

    Nakamura, Shinichi; Utsunomiya, Daisuke; Namimoto, Tomohiro; Yamashita, Yasuyuki; Awai, Kazuo; Nakaura, Takeshi; Morita, Kosuke

    2012-01-01

    The purpose of this study was to investigate the chronological relationship between scan delay and liver enhancement for the hepatobiliary phase on Gd-EOB-DTPA-enhanced MRI and evaluate the effects of liver function on liver enhancement. Hepatobiliary-phase images were retrospectively evaluated in 125 patients with chronic liver disease. Hepatobiliary phase images were obtained at 5, 10, 15, and 20 min after injection. We calculated relative liver enhancement (RLE) at t min after injection by dividing the signal intensity (SI) of the liver at t min by precontrast SI. We compared RLE values at 5, 10, 15, and 20 min and evaluated the detectability of focal hepatic lesions. We analyzed the effect of liver function on RLE with the generalized linear model. There was not significant difference in RLE and lesion detectability at 15 and 20 min. RLE in the Child-Pugh C group was significantly lower than in the Child-Pugh A and B groups. The serum albumin level and prothrombin time were significantly correlated with the liver enhancement. A delay time of 15 min for the hepatobiliary phase was thought to be adequate in patients with mild liver dysfunction. The serum albumin level and prothrombin time would be predictive of liver enhancement in the hepatobiliary phase. (author)

  16. Neuroradiologic findings in leptomeningeal carcinomatosis: The value interest of gadolinium-enhanced MRI

    International Nuclear Information System (INIS)

    Rodesch, G.; Baleriaux, D.; Bogaert, P. van; Mavroudakis, N.; Hildebrand, J.; Parizel, P.M.; Martin, J.J.; Segebarth, C.; Vyve, M. van

    1990-01-01

    Four patients with leptomeningeal metastases documented by neuroradiological examinations are reported. All had central nervous system or systemic neoplasms and showed clinical signs of carcinomatous meningitis. Gadolinium-enhanced MRI (Gd-MRI) disclosed for each patient pathological foci, allowing delineation of the extent of meningeal disease. Although non-specific, these findings, combined with the clinical context and CSF analysis, may lead to a rapid diagnosis and treatment of carcinomatous meningitis, even when malignant cells are not detected in the cerebrospinal fluid. (orig.)

  17. Delayed enhanced MRI in intraparenchymal tumors

    International Nuclear Information System (INIS)

    Eguchi, Takahiko; Morimoto, Tetsuya; Takeshima, Toshikazu

    1991-01-01

    Delayed enhanced MRI was performed on 20 intraparenchymal tumors, and these findings were compared with those of early enhanced MRI. Using the spin-echo technique (SE: 400-500/20 msec), early scans were obtained 5 minutes, and delayed scans were obtained 60 minutes, after the intravenous injection of 0.1 nmol of gadolinium-DTPA/Kg. We discussed the changes in the delayed scan with regard to the change in the pattern of enhancement and the boundary of enhancement. In these twenty intraparenchymal tumors, there were three low-grade astrocytomas, two anaplastic astrocytomas, seven glioblastomas, and eight metastatic tumors. The changes in the enhanced pattern showed three types as follows: Type I: heterogeneous enhancement in both early and delayed scans; Type II: heterogeneous enhancement in early scan and homogeneous enhancement in delayed scan; Type III: homogeneous enhancement in both early and delayed scans. Most malignant tumors, such as glioblastomas (6/8), anaplastic astrocytomas (2/2), and metastatic tumors (7/8), revealed Type I, although low-grade astrocytomas showed Type II (3/2) and Type III (1/3). The heterogeneous enhancement in delayed scan was found in malignant tumors and in low-grade astrocytoma; even if the early scan revealed heterogeneous enhancement, the delayed scan showed homogeneous enhancement. In the delayed scan, most enhanced boundaries spread out of the boundaries in the early scan. Glioblastomas spread markedly in the delayed scan, although none of the low-grade astrocytomas, anaplastic astrocytomas, or metastases revealed marked spreading. We called these marked increases in the delayed scan a 'spreading sign' and thought that this sign was specific to glioblastomas. Recently some authors have emphasized the usefulness of serial scans. Delayed enhanced MRI 60 minutes after the administration of a contrast medium was here found also to be useful for the accurate diagnosis for brain tumors. (author)

  18. Gadolinium-DTPA enhancement of symptomatic nerve roots in MRI of the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Tyrrell, P.N.M.; Cassar-Pullicino, V.N.; McCall, I.W. [Department of Diagnostic Imaging, The Institute of Orthopaedics, The Robert Jones and Agnes Hunt Orthopaedic and District Hospital NHS Trust, Oswestry, Shropshire SY10 7AG (United Kingdom)

    1998-02-01

    Disc prolapse presenting with sciatica may be associated with enhancement of the symptomatic nerve root following magnetic resonance imaging (MRI) with intravenous gadolinium (Gd)-DTPA. Previous studies have shown, however, that this does not occur in all cases. The aim of this study was to assess the incidence of nerve root enhancement in patients with sciatica and disc prolapse and to try to identify any specific features that might be associated with the phenomenon. A total of 227 patients presenting with low back pain and/or sciatica underwent a MRI study of the lumbar spine with intravenous contrast enhancement. Nineteen of 81 (23.5 %) patients with disc prolapse demonstrated nerve root enhancement. Nerve root enhancement had a highly significant association with sequestrated disc lesions (13/19, 68 %; P < 0.0005), and was primarily seen in the symptomatic ipsilateral nerve root (16/19, 84 %). The sensitivity of nerve root enhancement associated with disc prolapse was 23.5 % with a specificity of 95.9 %, a positive predictive value of 76 % and a negative predictive value of 69.3 %. Nerve root enhancement may be indicative of the symptomatic level but its poor sensitivity negates the routine use of Gd-DTPA in MRI for sciatica. (orig.) With 4 figs., 1 tab., 37 refs.

  19. Gadolinium-DTPA enhancement of symptomatic nerve roots in MRI of the lumbar spine

    International Nuclear Information System (INIS)

    Tyrrell, P.N.M.; Cassar-Pullicino, V.N.; McCall, I.W.

    1998-01-01

    Disc prolapse presenting with sciatica may be associated with enhancement of the symptomatic nerve root following magnetic resonance imaging (MRI) with intravenous gadolinium (Gd)-DTPA. Previous studies have shown, however, that this does not occur in all cases. The aim of this study was to assess the incidence of nerve root enhancement in patients with sciatica and disc prolapse and to try to identify any specific features that might be associated with the phenomenon. A total of 227 patients presenting with low back pain and/or sciatica underwent a MRI study of the lumbar spine with intravenous contrast enhancement. Nineteen of 81 (23.5 %) patients with disc prolapse demonstrated nerve root enhancement. Nerve root enhancement had a highly significant association with sequestrated disc lesions (13/19, 68 %; P < 0.0005), and was primarily seen in the symptomatic ipsilateral nerve root (16/19, 84 %). The sensitivity of nerve root enhancement associated with disc prolapse was 23.5 % with a specificity of 95.9 %, a positive predictive value of 76 % and a negative predictive value of 69.3 %. Nerve root enhancement may be indicative of the symptomatic level but its poor sensitivity negates the routine use of Gd-DTPA in MRI for sciatica. (orig.)

  20. Glypican-1-antibody-conjugated Gd-Au nanoclusters for FI/MRI dual-modal targeted detection of pancreatic cancer.

    Science.gov (United States)

    Huang, Xin; Fan, Chengqi; Zhu, Huanhuan; Le, Wenjun; Cui, Shaobin; Chen, Xin; Li, Wei; Zhang, Fulei; Huang, Yong; Sh, Donglu; Cui, Zheng; Shao, Chengwei; Chen, Bingdi

    2018-01-01

    Pancreatic cancer (PC) has a poor prognosis with high mortality, due to the lack of effective early diagnostic and prognostic tools. In order to target and diagnose PC, we developed a dual-modal imaging probe using Glypican-1 (GPC-1) antibody conjugated with Gd-Au nanoclusters (NCs; Gd-Au-NC-GPC-1). GPC-1 is a type of cell surface heparan sulfate proteoglycan, which is often highly expressed in PC. The probe was successfully prepared with a hydrodynamic diameter ranging from 13.5 to 24.4 nm. Spectral characteristics showed absorption at 280 nm and prominent emission at 650 nm. Confocal microscopic imaging showed effective detection of GPC-1 highly expressed PC cells by Gd-Au-NC-GPC-1, which was consistent with flow cytometry results. In vitro relaxivity characterization demonstrated that the r1 value of the probe was 17.722 s -1 mM -1 Gd, which was almost 4 times higher compared with that of Gd-diethylenetriaminepentacetate (DTPA; r1 value =4.6 s -1 mM -1 Gd). Gd-Au-NC-GPC-1 exhibited similar magnetic resonance (MR) signals when compared to Gd-DTPA even at lower Gd concentrations. Much higher MR signals were registered in PC cells (COLO-357) compared with normal cells (293T). Furthermore, Gd-Au-NC-GPC-1 could effectively detect PC cells in vivo by dual-modal fluorescence imaging/magnetic resonance imaging (FI/MRI) at 30 minutes postinjection. In addition, Gd-Au-NC-GPC-1 did not show significant biotoxicity to normal cells at tested concentrations both in vitro and in vivo. Gd-Au-NC-GPC-1 has demonstrated to be a promising dual-modal FI/MRI contrast agent for targeted diagnosis of PC.

  1. Expression of OATP1B3 determines uptake of Gd-EOB-DTPA in hepatocellular carcinoma

    OpenAIRE

    Narita, Masato; Hatano, Etsuro; Arizono, Shigeki; Miyagawa-Hayashino, Aya; Isoda, Hiroyoshi; Kitamura, Koji; Yasuchika, Kentaro; Nitta, Takashi; Uemoto, Shinji

    2009-01-01

    Background: Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) is an MRI contrast agent with perfusion and hepatoselective properties. The purpose of the study was to examine uptake of Gd-EOB-DTPA in the hepatobiliary phase in hepatocellular carcinoma (HCC). Methods: A retrospective analysis of 22 patients with HCC who underwent preoperative Gd-EOB-DTPA-enhanced MRI was performed. Enhancement ratios (ERs) and expression levels of the organic anion transporter (OATP) 1B3...

  2. Hyperintense hepatocellular carcinoma on gadolinium-enhanced hepatic MRI

    International Nuclear Information System (INIS)

    Yoshikawa, Jun; Matsui, Osamu; Kadoya, Masumi; Gabata, Toshifumi; Arai, Kazunori; Takashima, Tsutomu

    1992-01-01

    We reported a phenomenon in which some hepatocellular carcinomas (HHCs) visualized as hypointense on plain T1 weighted MR images became hyperintense on gadolinium-DTPA (Gd-DTPA) (0.06∼0.23 mmol/kg) enhanced delayed images. Gd-DTPA enhanced images (using a super conducting magnet operating at 1.5T) of 44 HCCs were studied in comparison with contrast enhanced CT using 30∼80g of iodine. Six of 44 HCCs (14%) which were visualized as hypointense on plain T1 weighted image became hyperintense on delayed Gd-DTPA enhanced images. Although these were visualized as low intensity areas on both plain and enhanced CT, the contrast between HCC and the surrounding liver was small on post contrast CT. These findings were thought to be due to a stronger enhancement effect of Gd-DTPA than that of iodine. (author)

  3. Tunable paramagnetic relaxation enhancements by [Gd(DPA)3]3- for protein structure analysis

    International Nuclear Information System (INIS)

    Yagi, Hiromasa; Loscha, Karin V.; Su, Xun-Cheng; Stanton-Cook, Mitchell; Huber, Thomas; Otting, Gottfried

    2010-01-01

    Paramagnetic relaxation enhancements (PRE) present a powerful source of structural information in nuclear magnetic resonance (NMR) studies of proteins and protein-ligand complexes. In contrast to conventional PRE reagents that are covalently attached to the protein, the complex between gadolinium and three dipicolinic acid (DPA) molecules, [Gd(DPA) 3 ] 3- , can bind to proteins in a non-covalent yet site-specific manner. This offers straightforward access to PREs that can be scaled by using different ratios of [Gd(DPA) 3 ] 3- to protein, allowing quantitative distance measurements for nuclear spins within about 15 A of the Gd 3+ ion. Such data accurately define the metal position relative to the protein, greatly enhancing the interpretation of pseudocontact shifts induced by [Ln(DPA) 3 ] 3- complexes of paramagnetic lanthanide (Ln 3+ ) ions other than gadolinium. As an example we studied the quaternary structure of the homodimeric GCN4 leucine zipper.

  4. Time course of epidural scar enhancement with Gd-DTPA in an animal model

    International Nuclear Information System (INIS)

    Blaser, S.I.; Ross, J.S.; Berridge, M.; Emery, S.; Bolesta, M.J.; Modic, M.T.; Masaryk, T.J.; Bohlman, H.

    1988-01-01

    In eight beagles following laminectomies, dynamic contrast enhancement of posterior epidural scar was assessed sequentially over 4 months by means of FLASH sequence (20/10/50) following Gd-DTPA. A consistent pattern of enhancement was apparent in all dogs. Maximum enhancement occurred after 1 month (80%-130%), with peak enhancement at 7-10 minutes. There was decreased enhancement each succeeding month with a similar time to peak. Time curves were obtained for blood, muscle, and scar following injection of 40 μCi Gd-153 DTPA and correlated well with in vivo MR image intensities. Histology showed granulation tissue early following surgery, which matured to scar by 4 months. These findings are in contrast to reports of enhancement of anterior scar in humans irrespective of age. The difference may be secondary to location in that posterior scar does not receive the trauma and stress acting on anterior scar associated with a degenerative disk

  5. Dynamic contrast-enhanced magnetic resonance imaging with Gd-EOB-DTPA for the evaluation of liver fibrosis in chronic hepatitis patients

    International Nuclear Information System (INIS)

    Chen, Bang-Bin; Hsu, Chao-Yu.; Yu, Chih-Wei; Wei, Shwu-Yuan; Shih, Tiffany Ting-Fang; Kao, Jia-Horng; Lee, Hsuan-Shu

    2012-01-01

    To develop a non-invasive MRI method for evaluation of liver fibrosis, with histological analysis as the reference standard. The study protocol was approved by the Institutional Review Board for Human Studies of our hospital, and written informed consent was obtained from all subjects. Seventy-nine subjects who received dynamic contrast-enhanced MRI (DCE-MRI) with Gd-EOB-DTPA were divided into three subgroups according to Metavir score: no fibrosis (n = 30), mild fibrosis (n = 34), and advanced fibrosis (n = 15). The DCE-MRI parameters were measured using two models: (1) dual-input single-compartment model for arterial blood flow (F a ), portal venous blood flow, total liver blood flow, arterial fraction (ART), distribution volume, and mean transit time; and (2) curve analysis model for Peak, Slope, and AUC. Statistical analysis was performed with Student's t-test and the nonparametric Kruskal-Wallis test. Slope and AUC were two best perfusion parameters to predict the severity of liver fibrosis (>F2 vs. ≤F2). Four significantly different variables were found between non-fibrotic versus mild-fibrotic subgroups: F a , ART, Slope, and AUC; the best predictor for mild fibrosis was F a (AUROC:0.701). DCE-MRI with Gd-EOB-DTPA is a noninvasive imaging, by which multiple perfusion parameters can be measured to evaluate the severity of liver fibrosis. (orig.)

  6. Delayed gadolinium-enhanced MRI of the meniscus (dGEMRIM) in patients with knee osteoarthritis: relation with meniscal degeneration on conventional MRI, reproducibility, and correlation with dGEMRIC

    International Nuclear Information System (INIS)

    Tiel, Jasper van; Kotek, Gyula; Krestin, Gabriel P.; Oei, Edwin H.G.; Reijman, Max; Bos, Pieter K.; Verhaar, Jan A.N.; Bron, Esther E.; Klein, Stefan; Weinans, Harrie

    2014-01-01

    To assess (1) whether normal and degenerated menisci exhibit different T1 GD on delayed gadolinium-enhanced MRI of the meniscus (dGEMRIM), (2) the reproducibility of dGEMRIM and (3) the correlation between meniscus and cartilage T1 GD in knee osteoarthritis (OA) patients. In 17 OA patients who underwent dGEMRIM twice within 7 days, meniscus and cartilage T1 GD was calculated. Meniscus pathology was evaluated on conventional MRI. T1 GD in normal and degenerated menisci were compared using a Student's t-test. Reproducibility was assessed using ICCs. Pearson's correlation was calculated between meniscus and cartilage T1 GD . A trend towards lower T1 GD in degenerated menisci (mean: 402 ms; 95 % CI: 359-444 ms) compared to normal menisci (mean: 448 ms; 95 % CI: 423-473 ms) was observed (p = 0.05). Meniscus T1 GD ICCs were 0.85-0.90. The correlation between meniscus and cartilage T1 GD was moderate in the lateral (r = 0.52-0.75) and strong in the medial compartment (r = 0.78-0.94). Our results show that degenerated menisci have a clear trend towards lower T1 GD compared to normal menisci. Since these results are highly reproducible, meniscus degeneration may be assessed within one delayed gadolinium-enhanced MRI simultaneously with cartilage. The strong correlation between meniscus and cartilage T1 GD suggests concomitant degeneration in both tissues in OA, but also suggests that dGEMRIC may not be regarded entirely as sulphated glycosaminoglycan specific. (orig.)

  7. Delayed gadolinium-enhanced MRI of the meniscus (dGEMRIM) in patients with knee osteoarthritis: relation with meniscal degeneration on conventional MRI, reproducibility, and correlation with dGEMRIC

    Energy Technology Data Exchange (ETDEWEB)

    Tiel, Jasper van [University Medical Center, Department of Orthopaedic Surgery, Erasmus MC, Rotterdam (Netherlands); University Medical Center, Department of Radiology, Erasmus MC, P.O. Box 2040, Rotterdam (Netherlands); Kotek, Gyula; Krestin, Gabriel P.; Oei, Edwin H.G. [University Medical Center, Department of Radiology, Erasmus MC, P.O. Box 2040, Rotterdam (Netherlands); Reijman, Max; Bos, Pieter K.; Verhaar, Jan A.N. [University Medical Center, Department of Orthopaedic Surgery, Erasmus MC, Rotterdam (Netherlands); Bron, Esther E.; Klein, Stefan [University Medical Center, Department of Radiology, Erasmus MC, P.O. Box 2040, Rotterdam (Netherlands); University Medical Center, Department of Medical Informatics, Erasmus MC, Rotterdam (Netherlands); Weinans, Harrie [University Medical Center, Department of Orthopaedic Surgery, Erasmus MC, Rotterdam (Netherlands); Delft University of Technology, Department of Biomechanical Engineering, Delft (Netherlands); University Medical Center, Department of Orthopaedic Surgery, Utrecht (Netherlands); University Medical Center, Department of Rheumatology, Utrecht (Netherlands)

    2014-09-15

    To assess (1) whether normal and degenerated menisci exhibit different T1{sub GD} on delayed gadolinium-enhanced MRI of the meniscus (dGEMRIM), (2) the reproducibility of dGEMRIM and (3) the correlation between meniscus and cartilage T1{sub GD} in knee osteoarthritis (OA) patients. In 17 OA patients who underwent dGEMRIM twice within 7 days, meniscus and cartilage T1{sub GD} was calculated. Meniscus pathology was evaluated on conventional MRI. T1{sub GD} in normal and degenerated menisci were compared using a Student's t-test. Reproducibility was assessed using ICCs. Pearson's correlation was calculated between meniscus and cartilage T1{sub GD}. A trend towards lower T1{sub GD} in degenerated menisci (mean: 402 ms; 95 % CI: 359-444 ms) compared to normal menisci (mean: 448 ms; 95 % CI: 423-473 ms) was observed (p = 0.05). Meniscus T1{sub GD} ICCs were 0.85-0.90. The correlation between meniscus and cartilage T1{sub GD} was moderate in the lateral (r = 0.52-0.75) and strong in the medial compartment (r = 0.78-0.94). Our results show that degenerated menisci have a clear trend towards lower T1{sub GD} compared to normal menisci. Since these results are highly reproducible, meniscus degeneration may be assessed within one delayed gadolinium-enhanced MRI simultaneously with cartilage. The strong correlation between meniscus and cartilage T1{sub GD} suggests concomitant degeneration in both tissues in OA, but also suggests that dGEMRIC may not be regarded entirely as sulphated glycosaminoglycan specific. (orig.)

  8. Gd-DTPA enhancement of the facial nerve in Ramsay Hunt's syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Tsutomu; Yanagida, Masahiro; Yamauchi, Yasuo (Kansai Medical School, Moriguchi, Osaka (Japan)) (and others)

    1992-10-01

    A total of 21 MR images in 16 Ramsay Hunt's syndrome were evaluated. In all images, the involved side of peripheral facial nerve were enhanced in intensity after Gd-DTPA. However, 2 cases had recovered facial palsy when MR images were taken. Nine of 19 cases with the enhancement of internal auditory canal portion had vertigo or tinnitus. Thus, it was suggested that the enhancement of internal auditory canal portion and clinical feature are closely related. (author).

  9. Gd-DTPA enhancement of the facial nerve in Ramsay Hunt's syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Tsutomu; Yanagida, Masahiro; Yamauchi, Yasuo [Kansai Medical School, Moriguchi, Osaka (Japan); and others

    1992-10-01

    A total of 21 MR images in 16 Ramsay Hunt's syndrome were evaluated. In all images, the involved side of peripheral facial nerve were enhanced in intensity after Gd-DTPA. However, 2 cases had recovered facial palsy when MR images were taken. Nine of 19 cases with the enhancement of internal auditory canal portion had vertigo or tinnitus. Thus, it was suggested that the enhancement of internal auditory canal portion and clinical feature are closely related. (author).

  10. Gd-DTPA enhancement of the facial nerve in Ramsay Hunt's syndrome

    International Nuclear Information System (INIS)

    Kato, Tsutomu; Yanagida, Masahiro; Yamauchi, Yasuo

    1992-01-01

    A total of 21 MR images in 16 Ramsay Hunt's syndrome were evaluated. In all images, the involved side of peripheral facial nerve were enhanced in intensity after Gd-DTPA. However, 2 cases had recovered facial palsy when MR images were taken. Nine of 19 cases with the enhancement of internal auditory canal portion had vertigo or tinnitus. Thus, it was suggested that the enhancement of internal auditory canal portion and clinical feature are closely related. (author)

  11. 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.

  12. Correlation of emmprin expression in vascular endothelial cells with blood-brain-barrier function: a study using magnetic resonance imaging enhanced by Gd-DTPA and immunohistochemistry in brain tumors.

    Science.gov (United States)

    Sameshima, Tetsuro; Nabeshima, Kazuki; Toole, Bryan P; Inoue, Teruhiko; Yokogami, Kiyotaka; Nakano, Shinichi; Ohi, Takekazu; Wakisaka, Shinichiro

    2003-06-01

    In a previous study, we demonstrated that the expression levels in tumor cells of emmprin (CD147) correlated with the grade of astrocytic tumors. Also, we found that emmprin was expressed in vascular endothelial cells of the non-neoplastic brain and hypothesized that emmprin expression could be associated with normal blood-brain-barrier (BBB) function of vascular endothelial cells. In this study, this possibility was examined in non-neoplastic brain, glioma and metastatic carcinoma tissues by comparing emmprin immunohistochemistry with gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) enhancement of magnetic resonance imaging (MRI), which is a clinical indicator of the BBB function. This study included 10 cases of non-neoplastic brain tissues, 7 of metastatic carcinoma, 7 of diffuse astrocytoma, 4 of anaplastic astrocytoma and 13 of glioblastoma multiforme. In all the cases, MRI with administration of Gd-DTPA was performed. The lesions were resected using the microdissection method with the help of ultrasonography and a neuronavigator. The tissues from Gd-DTPA-enhanced or non-enhanced areas were processed into frozen sections and subjected to immunohistochemistry with anti-emmprin antibody. The expression of emmprin in brain vascular endothelial cells inversely correlated with Gd-DTPA-enhancement of MRI: emmprin was positive in tissues not enhanced by Gd-DTPA and was negative in DTPA-enhanced tissues. Since BBB function presumably remains unimpaired in regions in which MR images are not Gd-DTPA-enhanced, emmprin expression appears to be associated with unimpaired BBB function. This is the first report to demonstrate a possible correlation between emmprin expression and BBB function in humans.

  13. Measurement of the arterial concentration of Gd-DTPA using MRI: a step toward quantitative perfusion imaging

    DEFF Research Database (Denmark)

    Fritz-Hansen, T; Rostrup, Egill; Larsson, H B

    1996-01-01

    A noninvasive method using an inversion recovery turbo-FLASH for dynamic measurement of the arterial input function represented by the bolus passage of Gd-DTPA in the descending aorta is presented, and the results are compared with the input function obtained by arterial blood samples. A good...... accordance between the two input functions was found, indicating that it is possible to measure the input function to the myocardium using MRI. A variation between the two concentration curves of 5% at upslope, 2.7% at peak point, and ... inversion time peak concentration....

  14. The interplay of T1- and T2-relaxation on T1-weighted MRI of hMSCs induced by Gd-DOTA-peptides.

    Science.gov (United States)

    Cao, Limin; Li, Binbin; Yi, Peiwei; Zhang, Hailu; Dai, Jianwu; Tan, Bo; Deng, Zongwu

    2014-04-01

    Three Gd-DOTA-peptide complexes with different peptide sequence are synthesized and used as T1 contrast agent to label human mesenchymal stem cells (hMSCs) for magnetic resonance imaging study. The peptides include a universal cell penetrating peptide TAT, a linear MSC-specific peptide EM7, and a cyclic MSC-specific peptide CC9. A significant difference in labeling efficacy is observed between the Gd-DOTA-peptides as well as a control Dotarem. All Gd-DOTA-peptides as well as Dotarem induce significant increase in T1 relaxation rate which is in favor of T1-weighted MR imaging. Gd-DOTA-CC9 yields the maximum labeling efficacy but poor T1 contrast enhancement. Gd-DOTA-EM7 yields the minimum labeling efficacy but better T1 contrast enhancement. Gd-DOTA-TAT yields a similar labeling efficacy as Gd-DOTA-CC9 and similar T1 contrast enhancement as Gd-DOTA-EM7. The underlying mechanism that governs T1 contrast enhancement effect is discussed. Our results suggest that T1 contrast enhancement induced by Gd-DOTA-peptides depends not only on the introduced cellular Gd content, but more importantly on the effect that Gd-DOTA-peptides exert on the T1-relaxation and T2-relaxation processes/rates. Both T1 and particularly T2 relaxation rate have to be taken into account to interpret T1 contrast enhancement. In addition, the interpretation has to be based on cellular instead of aqueous longitudinal and transverse relaxivities of Gd-DOTA-peptides. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Differentiation of prostate cancer from normal prostate tissue in an animal model: conventional MRI and dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Gemeinhardt, O.; Prochnow, D.; Taupitz, M.; Hamm, B.; Beyersdorff, D.; Luedemann, L.; Abramjuk, C.

    2005-01-01

    Purpose: to differentiate orthotopically implanted prostate cancer from normal prostate tissue using magnetic resonance imaging (MRI) and Gd-DTPA-BMA-enhanced dynamic MRI in the rat model. Material and methods: tumors were induced in 15 rats by orthotopic implantation of G subline Dunning rat prostatic tumor cells. MRI was performed 56 to 60 days after tumor cell implantation using T1-weighted spin-echo, T2-weighted turbo SE sequences, and a 2D FLASH sequence for the contrast medium based dynamic study. The interstitial leakage volume, normalized permeability and the permeability surface area product of tumor and healthy prostate were determined quantitatively using a pharmacokinetic model. The results were confirmed by histologic examination. Results: axial T2-weighted TSE images depicted low-intensity areas suspicious for tumor in all 15 animals. The mean tumor volume was 46.5 mm3. In the dynamic study, the suspicious areas in all animals displayed faster and more pronounced signal enhancement than surrounding prostate tissue. The interstitial volume and the permeability surface area product of the tumors increased significantly by 420% (p<0.001) and 424% (p<0.001), respectively, compared to normal prostate tissue, while no significant difference was seen for normalized permeability alone. Conclusion: the results of the present study demonstrate that quantitative analysis of contrast-enhanced dynamic MRI data enables differentiation of small, slowly growing orthotopic prostate cancer from normal prostate tissue in the rat model. (orig.)

  16. Enhanced MRI in patients with Ramsay-Hunt's syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Masahiro; Ushiro, Koichi; Yamashita, Toshio; Kumazawa, Tadami (Kansai Medical Univ., Osaka (Japan). Dept. of Otolaryngology); Katoh, Tsutomu (Kansai Medical Univ., Osaka (Japan). Dept. of Radiology)

    1993-01-01

    Enhanced MRI was performed in 14 patients with Ramsay-Hunt,s syndrome to investigate the pathogenesis of this syndrome. All MRI studies were performed on a 0.5T superconductivity MRI system using a head coil with Gd-DTPA. Enhancement was observed in the areas of the distal internal auditory canal and labyrinthine segment in many patients, and was especially prominent in patients suffering from vertigo, tinnitus, and hearing loss. In some patients it involved not only the facial nerve of the internal auditory canal but also the cochlear nerve and vestibular nerves. Since histological changes of the facial nerve in patients with Ramsay-Hunt's syndrome are assumed to occur in the distal internal auditory canal and labyrinthine segment, which is more proximal than the geniculate ganglion, and the possibility is suggested that inflammation may be spread to the vestibular and cochlear nerve via the internal auditory canal. (14 refs., 2 figs.).

  17. Gd-DOTA enhancement of cerebral and spinal tumors on MR imaging

    International Nuclear Information System (INIS)

    Berry, I.; Manelfe, C.; Chastin, I.; Arrue, P.; Prere, J.

    1987-01-01

    The use of Gd-DOTA as a contrast agent in MR imaging to improve the diagnosis of cerebral and spinal tumors was assessed in 20 patients, ten with brain tumors and ten with spinal tumors. Imaging was performed with a 0.5-T Magniscan 5000 unit. T1-weighted (spin-echo and gradient-echo) and T2-weighted (spin-echo) images were acquired before and after intravenous injection of Gd-DOTA, 0.1 mmol/kg. On T1-weighted images, Gd-DOTA enhanced sites of presumed disruption of the blood-brain barrier. This made some brain tumors more conspicuous and helped target biopsies, but did not reveal any additional lesions. On the other hand, the use of Gd-DOTA significantly improved the reliability of spinal tumor imaging compared to imaging performed without contrast agent, allowing delineation of abnormalities on T1-weighted images, which frequently contain fewer artifacts than the most sensitive T2-weighted images. Images obtained with Gd-DOTA could be used by the physician to rule out residual tumor after surgery and to assess recurrences. Additional work should be done to discover whether spinal tumor exploration with MR imaging could include solely T1-weighted sequences, performed before and after contrast agent administration, without T2-weighted sequences

  18. Brain Delivery of Drug and MRI Contrast Agent: Detection and Quantitative Determination of Brain Deposition of CPT-Glu Using LC-MS/MS and Gd-DTPA Using Magnetic Resonance Imaging

    Science.gov (United States)

    Tabanor, Kayann; Lee, Phil; Kiptoo, Paul; Choi, In-Young; Sherry, Erica B.; Eagle, Cheyenne Sun; Williams, Todd D.; Siahaan, Teruna J.

    2015-01-01

    Successful treatment and diagnosis of neurological diseases depend on reliable delivery of molecules across the blood-brain barrier (BBB), which restricts penetration of pharmaceutical drugs and diagnostic agents into the brain. Thus, developing new non-invasive strategies to improve drug delivery across the BBB is critically needed. This study was aimed at evaluating the activity of HAV6 peptide (Ac-SHAVSS-NH2) in improving brain delivery of camptothecin-glutamate (CPT-Glu) conjugate and gadolinium-diethylenetriaminepentaacetate (Gd-DTPA) contrast agent in Sprague-Dawley rats. Brain delivery of both CPT-Glu and Gd-DTPA was evaluated in an in situ rat brain perfusion model in the presence and absence of HAV6 peptide (1.0 mM). Gd-DTPA (0.6 mmol/kg) was intravenously (i.v.) administered with and without HAV6 peptide (0.019 mmol/kg) in rats. The detection and quantification of CPT-Glu and Gd-DTPA in the brain were carried out by LC-MS/MS and quantitative magnetic resonance imaging (MRI), respectively. Rats perfused with CPT-Glu in combination with HAV6 had significantly higher deposition of drug in the brain compared to CPT-Glu alone. MRI results also showed that administration of Gd-DTPA in the presence of HAV6 peptide led to significant accumulation of Gd-DTPA in various regions of the brain in both the in situ rat brain perfusion and in vivo studies. All observations taken together indicate that HAV6 peptide can disrupt the BBB and enhance delivery of small molecules into the brain. PMID:26705088

  19. Brain Delivery of Drug and MRI Contrast Agent: Detection and Quantitative Determination of Brain Deposition of CPT-Glu Using LC-MS/MS and Gd-DTPA Using Magnetic Resonance Imaging.

    Science.gov (United States)

    Tabanor, Kayann; Lee, Phil; Kiptoo, Paul; Choi, In-Young; Sherry, Erica B; Eagle, Cheyenne Sun; Williams, Todd D; Siahaan, Teruna J

    2016-02-01

    Successful treatment and diagnosis of neurological diseases depend on reliable delivery of molecules across the blood-brain barrier (BBB), which restricts penetration of pharmaceutical drugs and diagnostic agents into the brain. Thus, developing new noninvasive strategies to improve drug delivery across the BBB is critically needed. This study was aimed at evaluating the activity of HAV6 peptide (Ac-SHAVSS-NH2) in improving brain delivery of camptothecin-glutamate (CPT-Glu) conjugate and gadolinium-diethylenetriaminepentaacetate (Gd-DTPA) contrast agent in Sprague-Dawley rats. Brain delivery of both CPT-Glu and Gd-DTPA was evaluated in an in situ rat brain perfusion model in the presence and absence of HAV6 peptide (1.0 mM). Gd-DTPA (0.6 mmol/kg) was intravenously (iv) administered with and without HAV6 peptide (0.019 mmol/kg) in rats. The detection and quantification of CPT-Glu and Gd-DTPA in the brain were carried out by LC-MS/MS and quantitative magnetic resonance imaging (MRI), respectively. Rats perfused with CPT-Glu in combination with HAV6 had significantly higher deposition of drug in the brain compared to CPT-Glu alone. MRI results also showed that administration of Gd-DTPA in the presence of HAV6 peptide led to significant accumulation of Gd-DTPA in various regions of the brain in both the in situ rat brain perfusion and in vivo studies. All observations taken together indicate that HAV6 peptide can disrupt the BBB and enhance delivery of small molecules into the brain.

  20. Comparison of gadobenate dimeglumine (Gd-BOPTA) with gadopentetate dimeglumine (Gd-DTPA) for enhanced MR imaging of brain and spine tumours in children

    Energy Technology Data Exchange (ETDEWEB)

    Colosimo, Cesare [Univ. Annunzio, Chieti (Italy). Dept. of Clinical Sciences; Demaerel, Philippe [Univ. Hospital Leuven (Belgium); Tortori-Donati, Paolo [Inst. Gaslini, Genoa (Italy); Christophe, Catherine [Hopital Universitaire des Efants, Brussels (Belgium); Buchem, Mark van [Univ. Hospital Leiden (Netherlands); Hoegstroem, Barry; Pirovano, Gianpaolo; Shen, Ningyan; Spinazzi, Alberto [Worldwide Medical Affairs, Bracco Diagnostics, Inc., Princeton, NJ (United States); Kirchin, Miles A. [Worldwide Medical Affairs, Bracco Imaging SpA, Milan (Italy)

    2005-05-01

    Sixty-three subjects, aged 6 months to 16 years, who were enrolled in a prospective, fully blinded, randomized parallel-group phase III clinical trial, received 0.1 mmol/kg doses of either Gd-BOPTA (n=29) or Gd-DTPA (n=34). The MR images were acquired before and within 10 min of contrast agent injection. The primary objective was to compare the difference from pre-dose to post-dose lesion visualization between Gd-BOPTA and Gd-DTPA. Lesion visualization was determined as the sum of individual scores for three criteria of lesion morphological characteristics (lesion border delineation, internal morphology, and contrast enhancement), each assessed qualitatively using 4-point scales. Quantitative evaluation compared changes in lesion-to-background (LBR) and contrast-to-noise (CNR) ratios and per cent enhancement. Monitoring for adverse events and evaluation of vital signs and laboratory values was performed. Pre-dose to post-dose changes in lesion visualization were significantly better for Gd-BOPTA for both lesion level (2.68{+-}2.17 vs. 1.05{+-}1.90, P=0.0106) and patient level (2.55{+-}2.18 vs. 1.14{+-}1.68, P=0.0079) comparisons. The mean pre-dose to post-dose change in CNR was greater for Gd-BOPTA (9.13{+-}15.36) than Gd-DTPA (2.18{+-}9.90), but the difference was only marginally significant (P=0.0779; 95% CI: -0.553, 14.454) because of wide variations of signal intensity between lesions. Similar findings were obtained for LBR and per cent enhancement. No differences between the agents were noted in terms of safety parameters. (orig.)

  1. Dynamic gadolinium-enhanced MRI evaluation of porcine femoral head ischemia and reperfusion

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, T. [Clinic for Orthopaedics and Sports Traumatology, Dreifaltigkeits-Krankenhaus GmbH, Aachener Str. 445-449, 50933 Koeln (Germany); Drescher, W. [Department of Orthopaedics, Christian Albrechts University, Kiel (Germany); Becker, C. [Department of Orthopaedics, Heinrich Heine University, Duesseldorf (Germany); Sangill, R.; Stoedkilde-Joergensen, H. [Institute for Magnetic Resonance Imaging Tomography, University of Aarhus, Skejby Hospital, Aarhus (Denmark); Heydthausen, M. [Computing Center, Heinrich Heine University, Duesseldorf (Germany); Hansen, E.S.; Buenger, C. [Spine Section, Department of Orthopaedics, University of Aarhus (Denmark)

    2003-02-01

    To examine the potential of gadolinium (Gd)-enhanced dynamic MRI in the detection of early femoral head ischemia. Furthermore, to apply a three-compartment model to achieve a clinically applicable MR index for femoral head perfusion during the steady state and arterial hip joint tamponade.Design and materials In a porcine model femoral head perfusion was measured by radioactive tracer microspheres and by using a dynamic Gd-enhanced MRI protocol. Femoral head perfusion measurements and MRI tests were performed unilaterally before, during and after the experimentally induced ischemia of one of the hip joints. Ischemia was induced by increasing intra-articular pressure to 250 mmHg. All pigs showed ischemia of the femoral head epiphysis under hip joint tamponade followed by reperfusion to the same level as before joint tamponade. In two cases perfusion after removal of tamponade continued to be low. In dynamic MRI measurements increases in signal intensity were seen after intravenous infusion of Gd-DTPA, followed by a slow decrease in signal intensity. The signal-intensity curve during femoral head ischemia had a minor increase. Also the coefficient determined was a helpful indicator of femoral head ischemia. Femoral head blood flow as measured by microspheres fell significantly under joint tamponade. Early detection of this disturbed regional blood flow was possible using a dynamic MRI procedure. A biomathematical model resulted from the evaluation of the intervals of signal intensity over time which allows detection of bone blood flow changes at a very early stage. Using this new method earlier detection of femoral head necrosis may be possible. (orig.)

  2. 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)

  3. 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)

  4. SIMS imaging of gadolinium isotopes in tissue from Nephrogenic Systemic Fibrosis patients: Release of free Gd from magnetic resonance imaging (MRI) contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, Jerrold L. [Department of Pathology, SUNY Upstate Medical University, Syracuse, New York (United States); Chandra, Subhash [Cornell SIMS Laboratory, Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY 14853 (United States)], E-mail: sc40@cornell.edu; Thakral, Charu [Department of Pathology, SUNY Upstate Medical University, Syracuse, New York (United States); Abraham, Joshua M. [Cornell SIMS Laboratory, Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY 14853 (United States)

    2008-12-15

    Recently, Gd-based magnetic resonance imaging (MRI) contrast agents (GBMCA) have been linked to a new disease, Nephrogenic Systemic Fibrosis (NSF), with skin and systemic toxicity and death in certain patients with renal failure. Due to widespread use of GBMCA in diagnostic MRI, it is essential to study their excretion, metabolism, and target sites in cells and tissues. A CAMECA IMS-3f SIMS ion microscope and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) were used for imaging Gd isotopes in relation to calcium distributions in histologic sections of human tissues. SIMS imaging revealed two types of Gd localization in skin biopsies of patients who received GBMCA. The Gd was present in micrometer size deposits in association with calcium, and in detectable amounts in a more diffuse cellular distribution. Only the Gd-containing deposits associated with Ca and P were detectable using SEM/EDS. As only insoluble deposits remain in the biopsy tissues after aqueous and organic solvent processing of the tissue, our observations support release of free Gd from the GBMCA and selective localization of insoluble Gd in the target tissue from patients with NSF. This study opens new novel applications of SIMS for characterization of the safety of GBMCA.

  5. Enhanced population of side band of {sup 155}Gd in heavy-ion Coulomb excitation

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, Masumi; Hayakawa, Takehito; Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; and others

    1998-03-01

    In the Coulomb excitation of {sup 155}Gd with heavy projectiles, {sup 32}S, {sup 58}Ni and {sup 90}Zr, unexpectedly large enhancement of a positive-parity side band has been observed. This enhancement could not be reproduced by a Coulomb-excitation calculation taking into account the recommended upper limits of E1 or E3 transitions, which are compiled in the whole mass region, and is proportional to the electric field accomplished in the Coulomb-scattering process. (author)

  6. Optimal gadolinium dose level for magnetic resonance imaging (MRI) contrast enhancement of U87-derived tumors in athymic nude rats for the assessment of photodynamic therapy

    Science.gov (United States)

    Cross, Nathan; Varghai, Davood; Flask, Chris A.; Feyes, Denise K.; Oleinick, Nancy L.; Dean, David

    2009-02-01

    This study aims to determine the effect of varying gadopentetate dimeglumine (Gd-DTPA) dose on Dynamic Contrast Enhanced-Magnetic Resonance Imaging (DCE-MRI) tracking of brain tumor photodynamic therapy (PDT) outcome. Methods: We injected 2.5 x 105 U87 cells (derived from human malignant glioma) into the brains of six athymic nude rats. After 9, 12, and 13 days DCE-MRI images were acquired on a 9.4 T micro-MRI scanner before and after administration of 100, 150, or 200 μL of Gd-DTPA. Results: Tumor region normalized DCE-MRI scan enhancement at peak was: 1.217 over baseline (0.018 Standard Error [SE]) at the 100 μL dose, 1.339 (0.013 SE) at the 150 μL dose, and 1.287 (0.014 SE) at the 200 μL dose. DCE-MRI peak tumor enhancement at the 150 μL dose was significantly greater than both the 100 μL dose (p DTPA dose provided the greatest T1 weighted contrast enhancement, while minimizing negative T2* effects, in DCE-MRI scans of U87-derived tumors. Maximizing Gd-DTPA enhancement in DCE-MRI scans may assist development of a clinically robust (i.e., unambiguous) technique for PDT outcome assessment.

  7. MR imaging with Gd-DTPA enhancement in experimental acute injury of the spinal cord

    International Nuclear Information System (INIS)

    Hackney, D.B.; Asato, R.; Joseph, P.M.; McGrath, J.T.; Grossman, R.I.; Shetty, A.

    1986-01-01

    The authors performed MR imaging with Gd-DTPA enhancement in adult male Sprague-Dawley rats, with experimentally induced acute spinal cored injuries. After epidural compression of the spinal cored the pathologic changes of acute cord contusion were allowed to develop for 30 minutes to 4 hours. MR imaging was then performed at 1.4 T. Both short spin-echo (TR = 400 msec, TE = 15-20 msec) and long spin-echo (TR = 2,000 msec, TE = 100 msec) images were obtained. After the initial imaging, Gd-DTPA (0.1 mmol/kg) and Evans blue dye were administered intravenously and imaging was repeated. Enhancement of normal central gray matter was consistently observed. However, neither pathologic enhancement on MR images nor extravasation of Evans blue dye on histologic inspection were identified

  8. Synthesis and characterization of an MRI Gd-based probe designed to target the translocator protein

    International Nuclear Information System (INIS)

    Cerutti, Erika; Aime, Silvio; Damont, Annelaure; Dolle, Frederic; Baroni, Simona

    2013-01-01

    DPA-713 is the lead compound of a recently reported pyrazolo[1,5-a]pyrimidine acetamide series, targeting the translocator protein (TSPO 18 kDa), and as such, this structure, as well as closely related derivatives, have been already successfully used as positron emission tomography radioligands. On the basis of the pharmacological core of this ligands series, a new magnetic resonance imaging probe, coded DPA-C6-(Gd)DOTAMA was designed and successfully synthesized in six steps and 13% overall yield from DPA-713. The Gd-DOTA monoamide cage (DOTA = 1,4,7,10-tetraaza-cyclododecane-1,4,7,10-tetraacetic acid) represents the magnetic resonance imaging reporter, which is spaced from the phenyl-pyrazolo[1,5-a]pyrimidine acetamide moiety (DPA-713 motif) by a six carbon-atom chain. DPA-C6-(Gd)DOTAMA relaxometric characterization showed the typical behavior of a small-sized molecule (relaxivity value: 6.02 mM -1 s -1 at 20 MHz). The good hydrophilicity of the metal chelate makes DPAC6-(Gd)DOTAMA soluble in water, affecting thus its biodistribution with respect to the parent lipophilic DPA-713 molecule. For this reason, it was deemed of interest to load the probe to a large carrier in order to increase its residence lifetime in blood. Whereas DPA-C6-(Gd)DOTAMA binds to serum albumin with a low affinity constant, it can be entrapped into liposomes (both in the membrane and in the inner aqueous cavity). The stability of the supramolecular adduct formed by the Gd-complex and liposomes was assessed by a competition test with albumin. (authors)

  9. Experimental study of Gadofluorine M enhancement in early diagnosis of radiation brain injury by MRI in rats

    International Nuclear Information System (INIS)

    Bai Shoumin; Liao Chengde; Guo Ruomi; Huang Ying; Liang Biling; Shen Jun; Lu Taixiang

    2011-01-01

    Objective: To explore the value of Gadofluorine M, a novel MRI enhancement agent,in the diagnosis the early radiation brain injury. Methods: Seventy-two Wistar rats were randomly divided into 5 equal groups. To establish the radiation injury model, the rat's posterior brain was irradiated with 0 (blank controls), 25, 35, 45, 55, and 65 Gy, respectively. After irradiation MR plain scanning and Gadofluorine M enhancement scanning (after the T1WI and T2WI scanning Gf at the dosage of 0.1 mmol/kg was injected intravenously and scanning was performed again 12 h later) were performed once a week for 8 weeks. Another 12 rats were randomly divided into 2 equal groups to exposure to 55 and 65 Gy, respectively, and MR scanning was performed once a week for 8 weeks since the third week after MR. After T1WI and T2WI scanning Gd-DTPA was injected intravenously, MR was conducted again 30 min later, and Gf was injected intravenously (Gd-DTPA enhancement and Gf enhancement contrast). The MR image and the pixel count were compared. Since the third week 2 rats from the Gf enhancement scanning group and 1 rat from the Gd-DTPA enhancement and Gf enhancement contrast were killed after MR with their brains taken out to undergo pathological examination. Results: No abnormal signal changes were found in MRI in 25 and 35 Gy groups within 2 months after irradiation. A high signal in the Gf enhancement T1WI image was found in 45, 55, and 65 Gy groups within the period of 4-6 weeks after radiation. The signal intensity was significantly higher than that of the control, 25, and 35 Gy groups (F=2.15, P<0.05). The emerge time of this signal was negatively correlated with the dose of radiation (r =-0.62, P<0.05). When there was no obvious change was found by Gd-DTPA enhancement, a high signal representing change of injury could be found in Gf enhancement in the same rat. The signal intensity was significantly enhanced in Gf enhancement compared to the Gd-DTPA enhancement (F=2.74, P<0

  10. Comparison of triple dose versus standard dose gadolinium-DTPA for detection of MRI enhancing lesions in patients with primary progressive multiple sclerosis.

    Science.gov (United States)

    Filippi, M; Campi, A; Martinelli, V; Colombo, B; Yousry, T; Canal, N; Scotti, G; Comi, G

    1995-01-01

    This study was performed to evaluate whether a triple dose of gadolinium-DTPA (Gd-DTPA) increases the sensitivity of brain MRI for detecting enhancing lesions in patients with primary progressive multiple sclerosis (PPMS). T1 weighted brain MRI was obtained for 10 patients with PPMS in two sessions. In the first session, one scan was obtained five to seven minutes after the injection of 0.1 mmol/kg Gd-DTPA (standard dose). In the second session, six to 24 hours later, one scan before and two scans five to seven minutes and one hour after the injection of 0.3 mmol/kg Gd-DTPA (triple dose) were obtained. Four enhancing lesions were detected in two patients when the standard dose of Gd-DTPA was used. The numbers of enhancing lesions increased to 13 and the numbers of patients with such lesions to five when the triple dose of Gd-DTPA was used and to 14 and six in the one hour delayed scans. The mean contrast ratio for enhancing lesions detected with the triple dose of Gd-DTPA was higher than those for lesions present in both the standard dose (P DTPA many more enhancing lesions can be detected in patients with PPMS. This is important both for planning clinical trials and for detecting the presence of inflammation in vivo in the lesions of such patients. Images PMID:8530944

  11. A novel nitroreductase-enhanced MRI contrast agent and its potential application in bacterial imaging

    Directory of Open Access Journals (Sweden)

    Yun Liu

    2018-05-01

    Full Text Available Nitroreductases (NTRs are known to be able to metabolize nitro-substituted compounds in the presence of reduced nicotinamide adenine dinucleotide (NADH as an electron donor. NTRs are present in a wide range of bacterial genera and, to a lesser extent, in eukaryotes hypoxic tumour cells and tumorous tissues, which makes it an appropriate biomarker for an imaging target to detect the hypoxic status of cancer cells and potential bacterial infections. To evaluate the specific activation level of NTR, great efforts have been devoted to the development of fluorescent probes to detect NTR activities using fluorogenic methods to probe its behaviour in a cellular context; however, NTR-responsive MRI contrast agents are still by far underexplored. In this study, para-nitrobenzyl substituted T1-weighted magnetic resonance imaging (MRI contrast agent Gd-DOTA-PNB (probe 1 has been designed and explored for the possible detection of NTR. Our experimental results show that probe 1 could serve as an MRI-enhanced contrast agent for monitoring NTR activity. The in vitro response and mechanism of the NTR catalysed reduction of probe 1 have been investigated through LC–MS and MRI. Para-nitrobenzyl substituted probe 1 was catalytically reduced by NTR to the intermediate para-aminobenzyl substituted probe which then underwent a rearrangement elimination reaction to Gd-DOTA, generating the enhanced T1-weighted MR imaging. Further, LC–MS and MRI studies of living Escherichia coli have confirmed the NTR activity detection ability of probe 1 at a cellular level. This method may potentially be used for the diagnosis of bacterial infections. KEY WORDS: Nitroreductase, MRI contrast agent, Smart imaging probes, Bacterial imaging, Bacterial infection

  12. Incidence of enhancement of the optic nerve/sheath complex in fat-suppression orbit MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ho Kyu; Yoon, Kwon Ha; Choi, Choong Gon; Suh, Dae Chul [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    1995-04-15

    To elucidate the incidence of Gd-DTPA enhancement of the optic nerve/sheath complex (ONC) in patients with various ophthalmopathies using fat-suppression MRI. Orbit MRI with fat-suppression technique (ChemSat) was performed in 58 patients with normal and various orbital lesions. The fat-suppression MR was done with and without Gd-DTPA injection in all cases. MR findings were reviewed retrospectively in a blind fashion with respect to presence or absence of contrast enhancement of the ONC. Contrast enhancement of the ONC was seen in 86% (6/7) of cavernous sinus lesions, 80% (8/10) of intraconal lesions excluding the ONC, 57% (16/28) of ONC lesions, 38% (3/8) of ocular lesions, and 2% (1/55) of normal orbits. The ONC enhancement was the most common in optic nerve/sheath tumors (10/10), and pseudotumors (6/6), cavernous sinus dural arteriovenous malformations (3/3) and cavernous sinus thrombosis (2/2), and less frequently seen in optic neuritis (3/14). Enhancement of the ONC may be seen in lesions of the cavernous sinus and orbit other than optic nerve/sheath lesion.

  13. Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging and Multidetector-Row Computed Tomography for the Diagnosis of Hepatocellular Carcinoma: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Ye, Feng; Liu, Jun; Ouyang, Han

    2015-08-01

    The purpose of this meta-analysis was to compare the diagnostic accuracy of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and multidetector-row computed tomography (MDCT) for hepatocellular carcinoma (HCC).Medline, Cochrane, EMBASE, and Google Scholar databases were searched until July 4, 2014, using combinations of the following terms: gadoxetic acid disodium, Gd-EOB-DTPA, multidetector CT, contrast-enhanced computed tomography, and magnetic resonance imaging. Inclusion criteria were as follows: confirmed diagnosis of primary HCC by histopathological examination of a biopsy specimen; comparative study of MRI using Gd-EOB-DTPA and MDCT for diagnosis of HCC; and studies that provided quantitative outcome data. The pooled sensitivity and specificity of the 2 methods were compared, and diagnostic accuracy was assessed with alternative-free response receiver-operating characteristic analysis.Nine studies were included in the meta-analysis, and a total of 1439 lesions were examined. The pooled sensitivity and specificity for 1.5T MRI were 0.95 and 0.96, respectively, for 3.0T MRI were 0.91 and 0.96, respectively, and for MDCT were 0.74 and 0.93, respectively. The pooled diagnostic odds ratio for 1.5T and 3.0T MRI was 242.96, respectively, and that of MDCT was 33.47. To summarize, Gd-EOB-DTPA-enhanced MRI (1.5T and 3.0T) has better diagnostic accuracy for HCC than MDCT.

  14. Late Adverse Events after Enhanced and Unenhanced MRI and CT

    DEFF Research Database (Denmark)

    Azzouz, Manal; Rømsing, Janne; Thomsen, Henrik S.

    2014-01-01

    Prospective evaluation of frequency of late and very late adverse events in patients undergoing enhanced or unenhanced magnetic resonance imaging (MRI) or computed tomography (CT). The imaging procedure was performed according to the protocols of the department. All patients were contacted three...... of LAEs was significantly higher in the enhanced MRI (38%) and CT (27%) groups than unenhanced MRI (20%) and CT (16%) groups. The frequency of nausea, dizziness, abdominal pain and diarrhoea was significantly higher in the enhanced MRI group than in the MRI control group, while taste sensation...

  15. Optimizing signal intensity correction during evaluation of hepatic parenchymal enhancement on gadoxetate disodium-enhanced MRI: Comparison of three methods

    International Nuclear Information System (INIS)

    Onoda, Minori; Hyodo, Tomoko; Murakami, Takamichi; Okada, Masahiro; Uto, Tatsuro; Hori, Masatoshi; Miyati, Tosiaki

    2015-01-01

    Highlights: •Signal intensity is often used to evaluate hepatic enhancement with Gd-EOB-DTPA in the hepatobiliary phase. •Comparison of uncorrected signal intensity with T 1 value revealed signal intensity instability. •Measurement of uncorrected liver SI or SNR often yields erroneous results on late-phase gadoxetate MRI due to shimming and other optimization techniques. •Signal intensity corrected by scale and rescale slope from DICOM data gave comparable results. -- Abstract: Objective: To compare signal intensity (SI) correction using scale and rescale slopes with SI correction using SIs of spleen and muscle for quantifying multiphase hepatic contrast enhancement with Gd-EOB-DTPA by assessing their correlation with T 1 values generated from Look-Locker turbo-field-echo (LL-TFE) sequence data (ER-T 1 ). Materials and methods: Thirty patients underwent Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) in this prospective clinical study. For each patient, breath-hold T 1 -weighted fat-suppressed three-dimensional (3D) gradient echo sequences (e-THRIVE) were acquired before and 2 (first phase), 10 (second phase), and 20 min (third phase) after intravenous Gd-EOB-DTPA. Look-Locker turbo-field-echo (LL-TFE) sequences were acquired before and 1.5 (first phase), 8 (second phase), and 18 min (third phase) postcontrast. The liver parenchyma enhancement ratios (ER) of each phase were calculated using the SI from e-THRIVE sequences (ER-SI) and the T 1 values generated from LL-TFE sequence data (ER-T 1 ) respectively. ER-SIs were calculated in three ways: (1) comparing with splenic SI (ER-SI-s), (2) comparing with muscle SI (ER-SI-m), (3) using scale and rescale slopes obtained from DICOM headers (ER-SI-c), to eliminate the effects of receiver gain and scaling. For each of the first, second and third phases, correlation and agreement were assessed between each ER-SI and ER-T 1 . Results: In the first phase, all ER-SIs correlated weakly with ER-T 1 . In the second

  16. An increased flip angle in late phase Gd-EOB-DTPA MRI shows improved performance in bile duct visualization compared to T2w-MRCP

    Energy Technology Data Exchange (ETDEWEB)

    Stelter, Lars, E-mail: lars.stelter@charite.de [Klinik für Radiologie, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Freyhardt, Patrick, E-mail: patrick.freyhardt@charite.de [Klinik für Radiologie, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Grieser, Christian, E-mail: christian.grieser@charite.de [Klinik für Radiologie, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Walter, Thula, E-mail: thula.walter@charite.de [Klinik für Radiologie, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Geisel, Dominik, E-mail: dominik.geisel@charite.de [Klinik für Radiologie, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Baur, Alexander, E-mail: alexander.baur@charite.de [Klinik für Radiologie, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); and others

    2014-10-15

    Highlights: • EOB-MRC acquired with a flip angle of 35° revealed a better diagnostic performance compared to T2w-MRCP. • EOB-MRC increased the readers’ confidence in identifying anatomic variations of the biliary tree. • As EOB-MRC comprises functional information it is a valuable adjunct to T2w-MRCP. - Abstract: Objectives: To estimate the additional value of an increased flip angle of 35° in late phase Gd-EOB-DTPA-enhanced magnetic resonance cholangiography, as compared to T2w-MRCP. Methods: 40 adult patients underwent Gd-EOB-DTPA enhanced MRI of the liver including a T2-weighted 3D TSE MRCP (T2w-MRCP) as well as a late phase T1-weighted THRIVE sequences applying a flip angle of 35° (fa35). Two experienced observers evaluated the images regarding the delineation of the different biliary regions using a three-point grading system. A five-point scale was applied to determine the readers’ confidence in identifying anatomical variations of the biliary tree. ROI analysis was performed to compare the signal-to-noise (SNR) and contrast-to-noise (CNR) ratios. Results: The quality for visualizing the biliary tree differed between T2w-MRCP and fa35 (p = <0.001). Late phase EOB-MRC was rated as good for delineating the entire biliary system, whereas T2w-MRCP received an overall poor rating. Especially the depiction of the intrahepatic bile ducts was estimated as problematic in T2w-MRCP. T2w-MRCP and fa35 revealed a discordant assessment of anatomical variations in 12.5% of the cases, comprising a generally higher confidence level for fa35 (4.0 ± 1.1 vs. 2.2 ± 1.2, p = <0.001). SNR proofed to be significantly higher in fa35 (p = <0.001), whereas T2w-MRCP revealed a significantly higher CNR (<0.001). Conclusions: Gd-EOB-DTPA enhanced magnetic resonance cholangiography acquired with a flip angle of 35° revealed a better diagnostic performance compared to T2w-MRCP and might be a valuable adjunct in assessing functional bile duct abnormalities.

  17. 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.

  18. Gd-BOPTA-enhanced excretory MR urography without administration of diuretics

    International Nuclear Information System (INIS)

    Allkemper, T.; Tombach, B.; Heindel, W.

    2001-01-01

    Purpose: To evaluate the feasibility and clinical utility of Gd-BOPTA enhanced excretory magnetic resonance urography without additional administration of diuretics in correlation with conventional urography. Method: 15 preoperative patients with pelvic tumors were examined at 1.5 T using a breath-hold high-resolution 3D-FLASH sequence during first-pass as well as 5, 10, 15 minutes after iv. injection of 0.05 mmol/kg BW Gd-BOPTA (MultiHance trademark ) without administration of diuretics. Post-processed coronal and multiplanar MIP reconstructions were compared to conventional excretory urography with regard to morphologic accuracy, anatomic variability, filling defects, cause and level of obstruction or compression, tumor visibility, and time-effectiveness by two independent radiologists. Results: Visualization of the urinary tract by MRU was comparable to conventional excretory urography in 14 of 15 cases. Caliceal fornices were better delineated on conventional urographies, whereas MRU was considered superior in the assessment of the inferior ureter sections, the urinary bladder and obstructive tumors, whose extents could be clearly marked out. Examination times of both techniques were comparable. Conclusion: These first results show that non-diuretic Gd-BOPTA enhanced MRU is comparable to conventional excretory urography for the preoperative diagnosis of pelvic tumors. Further improvements of this technique seem possible by optimization of examination intervals and injection doses. (orig.) [de

  19. Functional evaluation of transplanted kidneys by Gd-DTPA enhanced turbo FLASH MR imaging

    International Nuclear Information System (INIS)

    Nakashima, Rumi; Yamashita, Yasuyuki; Tomiguchi, Seiji; Tsuji, Akinori; Takahashi, Mutsumasa

    1996-01-01

    We evaluated the usefulness of dynamic turbo FLASH MR imaging in the differential diagnosis of complications after renal transplantation in 17 patients (10 from living relatives and 7 from cadavers). Coronal turbo FLASH dynamic images were obtained every 5 sec for 5 min after an intravenous bolus injection of Gd-DTPA. Corticomedullary differentiation (CMD) on spin echo coronal T 1 -weighted images and MR renogram patterns of the renal cortex and medulla were obtained for quantitative analysis of the Gd-DTPA-enhanced dynamic turbo-FLASH images. The signal intensity ratio of the medulla to cortex after Gd-DTPA enhancement was compared among four groups: normal (n=9), acute tubular necrosis (ATN) or cyclosporine A (CyA) tubulopathy (n=6), acute rejection (AR) in the living related donor kidney (n=4), and AR in the cadaveric kidney (n=5). Although loss of CMD was seen in severe renal dysfunction in the transplanted kidneys, there was considerable overlap among the four groups. On dynamic study, there was significant differences in the signal intensity ratio of the medulla to cortex between normally functioning kidneys or ATN/CyA tubulopathy and AR (p<0.01). In patients with severe renal dysfunction, the arterial cortical peak was indistinct. In conclusion, MR renograms obtained from dynamic turbo FLASH MR imaging played a significant role in evaluating dysfunction of the renal transplant. (author)

  20. Enhancement of intracranial meningeal lesions with Gd-DTPA MR imaging

    International Nuclear Information System (INIS)

    Brown, E.; De La Paz, R.

    1989-01-01

    Pathologic intracranial meningeal enhancement on Gd-DTPA MR images (T1-weighted spin-echo sequence, 800/20 [repetition time msec/echo time msec] 1.5 T) was evaluated in 23 patients. Diagnoses included metastatic neoplasm (13 cases), benign neoplasm (four), infection (one), subarachnoid hemorrhage (three), and subdural hematoma (two). Eleven patients had undergone previous surgery. Diffuse enhancement occurred in 11 patients: eight with malignant infiltration, two with postoperative inflammation, and one with meningitis. Focal enhancement occurred in 12 patients, equally divided between those with malignant and benign processes: six cases were adjacent to intra- or extra-axial malignancy; three were at sites of recent (1--3 weeks) subarachnoid hemorrhage; and three were postoperative, adjacent to a craniotomy or subdural hematoma. Meningeal lesions were rarely diagnosed on the precontrast images, and Gd-DTPA enhancement was needed to distinguish between thickened meninges and thin fluid collections. Precontrast T1- and T2-weighted images were needed to discriminate high-signal meningeal enhancement from subacute subdural or subarachnoid hemorrhage, diploic marrow, normal vascular structures, and benign dural plaques. Meningeal enhancement was not pathology specific, and precontrast images are recommended to avoid misdiagnosis of subacute hemorrhage and misinterpretation of normal anatomy

  1. Patients with liver FNH and HCC patients with negative AFP: plain and dynamic enhanced MRI and CT findings

    Directory of Open Access Journals (Sweden)

    LI Mingtong

    2015-05-01

    Full Text Available ObjectiveTo investigate plain and dynamic enhanced magnetic resonance imaging (MRI and computed tomography (CT findings in patients with focal nodular hyperplasia (FNH of the liver and hepatocellular carcinoma (HCC patients with negative alpha-fetoprotein (AFP. MethodsA statistical analysis was performed on the clinical data of 124 cases of liver tumor admitted to Beijing Miyun County Hospital from April 2012 to April 2014. ResultsFifty-five of the 74 patients with FNH underwent CT examination, among whom 38 patients received three-phase dynamic enhanced scan and 16 received only plain scan; 62 cases had plain and enhanced MRI with the application of contrast agent Gd-BOPTA in 42 patients. Among the 50 HCC patients with negative AFP, CT examination was performed in 40 and 10 only had plain scan; 46 patients received plain and enhanced MRI with the use of contrast agent Gd-BOPTA in 30. Delayed scan after 1-2 h demonstrated low signal in 30 lesions of the 30 cases. ConclusionFor patients with liver FNH and AFP-negative HCC patients, their plain and dynamic enhanced MRI and CT scan have respective characteristics. A combination of multiple examination methods can significantly improve diagnostic yield of the two diseases.

  2. Gd-DTPA-Dopamine-Bisphytanyl Amphiphile: Synthesis, Characterisation and Relaxation Parameters of the Nanoassemblies and Their Potential as MRI Contrast Agents.

    Science.gov (United States)

    Gupta, Abhishek; Willis, Scott A; Waddington, Lynne J; Stait-Gardner, Tim; de Campo, Liliana; Hwang, Dennis W; Kirby, Nigel; Price, William S; Moghaddam, Minoo J

    2015-09-28

    Here, a new amphiphilic magnetic resonance imaging (MRI) contrast agent, a Gd(III)-chelated diethylenetriaminepentaacetic acid conjugated to two branched alkyl chains via a dopamine spacer, Gd-DTPA-dopamine-bisphytanyl (Gd-DTPA-Dop-Phy), which is readily capable of self-assembling into liposomal nanoassemblies upon dispersion in an aqueous solution, is reported. In vitro relaxivities of the dispersions were found to be much higher than Magnevist, a commercially available contrast agent, at 0.47 T but comparable at 9.40 T. Analysis of variable temperature (17)O NMR transverse relaxation measurements revealed the water exchange of the nanoassemblies to be faster than that previously reported for paramagnetic liposomes. Molecular reorientation dynamics were probed by (1)H NMRD profiles using a classical inner and outer sphere relaxation model and a Lipari-Szabo "model-free" approach. High payloads of Gd(III) ions in the liposomal nanoassemblies made solely from the Gd-DTPA-Dop-Phy amphiphiles, in combination with slow molecular reorientation and fast water exchange makes this novel amphiphile a suitable candidate to be investigated as an advanced MRI contrast agent. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. T1 Gd-enhanced compared with CISS sequences in retinoblastoma: superiority of T1 sequences in evaluation of tumour extension

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, Elke R.; Wanke, Isabel; Guengoer, Ali-Riza; Forsting, Michael [University Hospital, Department of Diagnostic and Interventional Neuroradiology, Essen (Germany); Jurklies, Christine [University Hospital Essen, Department of Ophthalmology (Germany)

    2005-01-01

    Background As adequate therapy for retinoblastoma in young children depends on infiltration of extra-retinal structures, diagnostic modalities play an essential role. Methods: In this widely extended study, 80 children with retinoblastoma were studied with MRI (standard fat-suppressed Gd-enhanced T1, T2 thin-slice sequences (additionally with small loop surface coil), constructive interference in steady state (CISS) sequence covering the orbita). The images were analysed by two blinded neuroradiologists. Histology was used as the gold standard. MRI assumed infiltration of extra-retinal structures in 13 of 80 patients of which ten were confirmed by histology. Affected extra-retinal structures were: optic nerve (five, of which two were on CISS and three on T1 with higher image resolution using the surface coil), scleral infiltration (five, of which four on CISS and T1) and ciliary body infiltration (one on CISS and T1). Another 61 enucleated patients did not have any extra-retinal infiltration in histology. The CISS sequence with multiplanar reconstruction was mainly helpful in revealing exact three-dimensional tumour extension with excellent clinical acceptance and pre-surgical planning but T1 fat-suppressed Gd-enhanced images were superior in revealing exact tumour extension. CISS sequences allow to produce excellent anatomical images and to perform multiplanar reconstruction to better demonstrate tumour extension. However, T1-weighted sequences after contrast application are more sensitive (60 versus 40%) in detecting infiltration of the optic nerve but equal in detecting scleral infiltration. (orig.)

  4. Reproducibility of intrarenal kinetics of Gd-DOTA with rabbits with dynamic MRI

    International Nuclear Information System (INIS)

    Grenier, N.; Broussin, J.; Barat, J.L.; Ducassou, D.

    1989-01-01

    Ten normal rabbits and seven rabbits with experimental acute renal failure by tubular necrosis were studied with dynamic MR to evaluate the reproducibility of intrarenal kinetics of Gd-DOTA. Sequential spin-echo sequences with short TR (200 msec)/TE (26 msec) were used yielding a 29 sec acquisition time. A usual semi-quantitative analysis of intrarenal contrast demonstrated the reproducilibity of some phases of the dynamic sequence in particular a drop in the signal within inner medulla between the third and the fourth minute after infusion. This effect, related to a high concentration of Gd-DOTA within the tubules was observed in 9 over 10 normal rabbits and in none of the rabbits with acute renal failure. The quantitative analysis calculation was based on relative signal intensity and contrast-to-noise ratio from the absolute signal intensity measure on regions-of-interest (ROI) on the cortex, outer medulla and inner medulla. No reproducibility of the variations with time of these parameters could be assessed. A gread number of factors of variations or error, mainly during the measurements of signal intensity with ROI, could explain this lack of reproducibility. At the present, dynamic MR is therefore not able to quantitatively evaluate the renal function. Only a semi-quantitative estimation of tubular concentration can be deduced [fr

  5. Dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) for the assessment of Pc 4-sensitized photodynamic therapy of a U87-derived glioma model in the athymic nude rat

    Science.gov (United States)

    Anka, Ali; Thompson, Paul; Mott, Eric; Sharma, Rahul; Zhang, Ruozhen; Cross, Nathan; Sun, Jiayang; Flask, Chris A.; Oleinick, Nancy L.; Dean, David

    2010-02-01

    Introduction: Dynamic Contrast-Enhanced-Magnetic Resonance Imaging (DCE-MRI) may provide a means of tracking the outcome of Pc 4-sensitized photodynamic therapy (PDT) in deeply placed lesions (e.g., brain tumors). We previously determined that 150 μL of gadolinium (Gd-DTPA) produces optimal enhancement of U87-derived intracerebral tumors in an athymic nude rat glioma model. We wish to determine how consistently DCE-MRI enhancement will detect an increase in Gd-enhancement of these tumors following Pc 4-PDT. Methods: We injected 2.5 x 105 U87 cells into the brains of 6 athymic nude rats. After 7-8 days pre-Pc 4 PDT peri-tumor DCE-MRI images were acquired on a 7.0T microMRI scanner before and after administration of 150 μL Gd. DCE-MRI scans were repeated on Days 11, 12, and 13 following Pc 4-PDT (Day 8 or 9). Results: Useful DCE-MRI data were obtained for these animals before and after Pc 4- PDT. In the pre-Pc 4-PDT DCE-MRI scans an average normalized peak Gd enhancement was observed in tumor tissue that was 1.297 times greater than baseline (0.035 Standard Error [SE]). The average normalized peak Gd enhancement in the tumor tissue in the scan following PDT (Day 11) was 1.537 times greater than baseline (0.036 SE), a statistically significant increase in enhancement (p = 0.00584) over the pre-PDT level. Discussion: A 150 μL Gd dose appears to provide an unambiguous increase in signal indicating Pc 4-PDT-induced necrosis of the U87-derived tumor. Our DCEMRI protocol may allow the development of a clinically robust, unambiguous, non-invasive technique for the assessment of PDT outcome.

  6. Hepatobiliary contrast agents for contrast-enhanced MRI of the liver: properties, clinical development and applications

    International Nuclear Information System (INIS)

    Reimer, Peter; Schneider, Guenter; Schima, Wolfgang

    2004-01-01

    Hepatobiliary contrast agents with uptake into hepatocytes followed by variable biliary excretion represent a unique class of cell-specific MR contrast agents. Two hepatobiliary contrast agents, mangafodipir trisodium and gadobenate dimeglumine, are already clinically approved. A third hepatobiliary contrast agent, Gd-EOB-DTPA, is under consideration. The purpose of this review is to provide an overview on the properties, clinical development and application of these three hepatobiliary contrast agents. Bolus injectable paramagnetic hepatobiliary contrast agents combine established features of extracellular agents with the advantages of hepatocyte specificity. The detection and characterisation of focal liver disease appears to be improved compared to unenhanced MRI, MRI with unspecific contrast agents and contrast-enhanced CT. To decrease the total time spent by a patient in the MR scanner, it is advisable to administer the agent immediately after acquisition of unenhanced T1-w MRI. After infusion or bolus injection (with dynamic FS-T1-w 2D or 3D GRE) of the contrast agent, moderately and heavily T2w images are acquired. Post-contrast T1-w MRI is started upon completion of T2-w MRI for mangafodipir trisodium and Gd-EOB-DTPA as early as 20 min following injection, while gadobenate dimeglumine scans are obtained >60 min following injection. Post-contrast acquisition techniques with near isotropic 3D pulse sequences with fat saturation parallel the technical progress made by MSCT combined with an unparalleled improvement in tumour-liver contrast. The individual decision that hepatobiliary contrast agent one uses is partly based on personal preferences. No comparative studies have been conducted comparing the advantages or disadvantages of all three agents directly against each other. (orig.)

  7. Diagnostic value of Gd-EOB-DTPA-enhanced MR cholangiography in non-invasive detection of postoperative bile leakage.

    Science.gov (United States)

    Kul, Melahat; Erden, Ayşe; Düşünceli Atman, Ebru

    2017-04-01

    To assess the diagnostic value of dynamic T 1 weighted (T1w) gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid (Gd-EOB-DTPA)-enhanced MR cholangiography (MRC) for the detection of active bile leaks. A total of 28 patients with suspected biliary leakage who underwent routine T 2 weighted (T2w) MRC and T1w GD-EOB-DTPA-enhanced MRC at our institution from February 2013 to June 2016 were included in this study. The image sets were retrospectively analyzed in consensus by three radiologists. T1w Gd-EOB-DTPA-enhanced MRC findings were correlated with clinical data, follow-up examinations and findings of invasive/surgical procedures. Patients with positive bile leak findings in Gd-EOB-DTPA-enhanced MRC were divided into hepatobiliary phase (HBP) (20-30 min) and delayed phase (DP) (60-390 min) group according to elapsed time between Gd-EOB-DTPA injection and initial bile leak findings in MRC images. These groups were compared in terms of laboratory test results (total bilirubin, liver enzymes) and the presence of bile duct dilatation in T2w MRC images. In each patient, visualization of bile ducts was sufficient in the HBP. The accuracy, sensitivity and specificity of dynamic Gd-EOB-DTPA-enhanced T1w MRC in the detection of biliary leaks were 92.9%, 90.5% and 100%, respectively (p  0.05). Three patients, each of them in DP group, showed normal laboratory test results and bile duct diameters. Dynamic T1w Gd-EOB-DTPA-enhanced MRC is a useful non-invasive diagnostic tool to detect bile leak. Advances in knowledge: Prolonged DP imaging may be required for bile leak detection even if visualization of biliary tree is sufficient in HBP and liver function tests, total bilirubin levels and bile duct diameters are normal.

  8. Enhanced MRI in carpal tunnel syndrome

    International Nuclear Information System (INIS)

    Hayakawa, Katsuhiko; Nakane, Takashi; Kobayashi, Shigeru; Asai, Takahiro; Wada, Kunio; Yoshizawa, Hidezo

    1998-01-01

    In this study, we performed contrast-enhanced MRI in patients with idiopathic carpal tunnel syndrome and examined the morphologic change in the carpal tunnel. In the transverse section of the opening of carpal tunnel where scaphoid and pisiform bones are figured out, we measured and examined 4 items, viz. the soft carpal tunnel volume, flat rate of median nerve, position of median nerve and thickness of palmer ligaments composing the base of carpal tunnel, with an image analyzer attached to the MRI apparatus. Whereas the average carpal tunnel volume in 12 hands of normal controls was 166.8 mm 2 , that in 74 hands of carpal tunnel syndrome was 207.2 mm 2 , a significant increase compared with the normal controls. The flat rate of median nerve was 46% in the controls, but that was 37.5% in the carpal tunnel syndrome, a significant flattening was noted. We connected the peaks of the scaphoid node and pisiform bone with a line and named it standard line. When we observed the position of median nerve in the carpal tunnel, the nerve in 9 of 12 hands, 75%, lay below the standard line in the controls, but the nerve in 65 of 74 hands, 87.8%, lay above the standard line in the carpal tunnel syndrome, clearly showing that the median nerve had shifted to the palmar side. Regarding these morphologic changes of the carpal tunnel, the internal pressure of the carpal tunnel is considered to be raised with swelling of the soft tissues mainly composing the inside of carpal tunnel, thus the area of cross section of carpal tunnel to be increased, the median nerve to be shifted to the palmar side and the median nerve to be compressed by the transverse carpal ligament at that time. Although we can observe these morphological changes readily in MRI images, these images show only the results of carpal tunnel syndrome after all, and do not specify the direct causes. However, we believe that these facts are important factors in the manifestation of idiopathic carpal tunnel syndrome. (author)

  9. Fingolimod in active multiple sclerosis: an impressive decrease in Gd-enhancing lesions

    NARCIS (Netherlands)

    Muris, A.H.; Rolf, L.; Damoiseaux, J.; Koeman, E.; Hupperts, R.

    2014-01-01

    Background: Fingolimod is a disease modifying therapy (DMT) in highly active relapsing remitting multiple sclerosis (RRMS), as is natalizumab. Fingolimod decreases annual relapse rates and gadolinium enhancing lesions on MRI as compared to either interferon beta (IFNβ) or placebo. The effect of

  10. Functionalized multimodal ZnO@Gd{sub 2}O{sub 3} nanosystems to use as perspective contrast agent for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Babayevska, Nataliya, E-mail: natbab@amu.edu.pl; Florczak, Patryk; Woźniak-Budych, Marta; Jarek, Marcin; Nowaczyk, Grzegorz; Zalewski, Tomasz; Jurga, Stefan

    2017-05-15

    Highlights: • The multimodal ZnO@Gd{sub 2}O{sub 3} nanostructures were obtained by wet chemistry methods. • FA and Dox have been effectively bonded onto the ZnO nanoparticles surface. • Functionalized ZnO@Gd{sub 2}O{sub 3} NPs are good contrast agents, useful for MR imaging. - Abstract: The main aim of this research was the synthesis of the multimodal hybrid ZnO@Gd{sub 2}O{sub 3} nanostructures as prospective contrast agent for Magnetic Resonance Imaging (MRI) for bio-medical applications. The nanoparticles surface was functionalized by organosilicon compounds (OSC) then, by folic acid (FA) as targeting agent and doxorubicin (Dox) as chemotherapeutic agent. Doxorubicin and folic acid were attached to the nanoparticles surface by amino groups as well as due to attractive physical interactions. The morphology and crystallography of the nanostructures were studied by HRTEM and SAXS techniques. After ZnO nanoparticles surface modification by Gd{sup 3+} and annealing at 900 °C, ZnO@Gd{sub 2}O{sub 3} nanostructures are polydispersed with size 30–100 nm. NMR (Nuclear Magnetic Resonance) studies of ZnO@Gd{sub 2}O{sub 3} were performed on fractionated particles with size up to 50 nm. Fourier transform infrared spectroscopy (FTIR), UV–vis spectroscopy, zeta-potential measurements and energy dispersive X-ray analysis (EDX) showed that functional groups have been effectively bonded onto the nanoparticles surface. The high adsorption capacity of folic acid (up to 20%) and doxorubicin (up to 40%) on nanoparticles was reached upon 15 min of adsorption process in a temperature-dependent manner. The nuclear magnetic resonance (NMR) relaxation measurements confirmed that the obtained ZnO@Gd{sub 2}O{sub 3} nanostructures could be good contrast agents, useful for magnetic resonance imaging.

  11. 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

  12. Can unenhanced multiparametric MRI substitute gadolinium-enhanced MRI in the characterization of vertebral marrow infiltrative lesions?

    Directory of Open Access Journals (Sweden)

    Dalia Z. Zidan

    2014-06-01

    Conclusion: Unenhanced-multiparametric MRI is compatible with gadolinium-enhanced MRI in reliable characterization of marrow infiltrative lesions. The routine MRI protocol of cancer patients should be altered to accommodate the evolving MRI technology and cost effectively substitute the need for a gadolinium enhanced scan.

  13. Optimization of the reference region method for dual pharmacokinetic modeling using Gd-DTPA/MRI and (18) F-FDG/PET.

    Science.gov (United States)

    Poulin, Éric; Lebel, Réjean; Croteau, Étienne; Blanchette, Marie; Tremblay, Luc; Lecomte, Roger; Bentourkia, M'hamed; Lepage, Martin

    2015-02-01

    The combination of MRI and positron emission tomography (PET) offers new possibilities for the development of novel methodologies. In pharmacokinetic image analysis, the blood concentration of the imaging compound as a function of time, [i.e., the arterial input function (AIF)] is required for MRI and PET. In this study, we tested whether an AIF extracted from a reference region (RR) in MRI can be used as a surrogate for the manually sampled (18) F-FDG AIF for pharmacokinetic modeling. An MRI contrast agent, gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) and a radiotracer, (18) F-fluorodeoxyglucose ((18) F-FDG), were simultaneously injected in a F98 glioblastoma rat model. A correction to the RR AIF for Gd-DTPA is proposed to adequately represent the manually sampled AIF. A previously published conversion method was applied to convert this AIF into a (18) F-FDG AIF. The tumor metabolic rate of glucose (TMRGlc) calculated with the manually sampled (18) F-FDG AIF, the (18) F-FDG AIF converted from the RR AIF and the (18) F-FDG AIF converted from the corrected RR AIF were found not statistically different (P>0.05). An AIF derived from an RR in MRI can be accurately converted into a (18) F-FDG AIF and used in PET pharmacokinetic modeling. © 2014 Wiley Periodicals, Inc.

  14. An MRI Method To Map Tumor Hypoxia Using Red Blood Cells Loaded with a pO2-Responsive Gd-Agent.

    Science.gov (United States)

    Di Gregorio, Enza; Ferrauto, Giuseppe; Gianolio, Eliana; Lanzardo, Stefania; Carrera, Carla; Fedeli, Franco; Aime, Silvio

    2015-08-25

    Hypoxia is a typical hallmark of many solid tumors and often leads to therapy resistance and the development of a more aggressive cancer phenotype. Oxygen content in tissues has been evaluated using numerous different methods for several imaging modalities, but none has yet reached the required standard of spatial and temporal resolution. Magnetic Resonance Imaging (MRI) appears to be the technique of choice and several pO2-responsive probes have been designed for it over the years. In vivo translation is often hampered in Gd-relaxation agents as it is not possible to separate effects that arise from changes in local concentration from those associated with responsive properties. A novel procedure for the MRI based assessment of hypoxia is reported herein. The method relies on the combined use of Gd-DOTP- and Gd-HPDO3A-labeled red blood cells (RBCs) where the first probe acts as a vascular oxygenation-responsive agent, while the second reports the local labeled RBC concentration in a transplanted breast tumor mouse model. The MRI assessment of oxygenation state has been validated by photoacoustic imaging and ex vivo immunofluorescence. The method refines tumor staging in preclinical models and makes possible an accurate monitoring of the relationship between oxygenation and tumor growth.

  15. Pharmacokinetic analysis of Gd-DTPA enhancement in dynamic MR of breast carcinoma

    International Nuclear Information System (INIS)

    Hess, T.; Knopp, M.V.; Hoffmann, U.; Brix, G.; Junkermann, H.; Zuna, I.; Fournier, D. von; Kaick, G. van

    1994-01-01

    Dynamic Gd-DTPA enhanced MR of the breast was performed in one single slice in 27 patients with suspicious nodular lesions. The results could be histologically verified in all cases. A rapid spin-echo sequence with a time resolution of 8.75 s was used for the dynamic examination. The signal changes were analysed using a pharmacokinetic model which allowed parametrization of the contrast enhancement and transformation of the data into colour coded parameter images. The parameters allowed reliable distinction of 9 benign from 18 malignant lesions (p 21 ''). One fibroadenoma could not be distinguished from the carcinomas. Lymph node metastases and the pharmacokinetic parameter amplitude correlated significantly (p<0.05). (orig.)

  16. Impact of gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance on the non-invasive diagnosis of small hepatocellular carcinoma: a prospective study.

    Science.gov (United States)

    Granito, A; Galassi, M; Piscaglia, F; Romanini, L; Lucidi, V; Renzulli, M; Borghi, A; Grazioli, L; Golfieri, R; Bolondi, L

    2013-02-01

    Gadoxetic acid (Gd-EOB-DTPA) is a 'hepatocyte-specific' contrast agent for magnetic resonance (MR) in both the vascular and the hepatobiliary phases. To evaluate the contribution of the hepatobiliary phase of Gd-EOB-DTPA MR in the diagnosis of small hepatocellular carcinoma (HCC) in cirrhotic patients under surveillance. Between 2008 and 2011, 48 consecutive small (10-30 mm) liver nodules were detected in 33 patients, who prospectively underwent contrast-enhanced ultrasound (CEUS), Gd-EOB-DTPA-enhanced MR and helical-computed tomography (CT) in a blind study. The diagnosis of HCC was established according to AASLD 2005 criteria. Of the 48 nodules, 38 (79%) were diagnosed as HCC, 24 (63%) of them based on AASLD non-invasive criteria, 11 diagnosed at histology and 3 during follow-up. The typical vascular pattern (arterial hypervascularisation and venous/late washout) was detected in 30 (79%) HCC nodules by MR, in 22 (58%) by CT and in 17 (45%) by CEUS. Hypointensity during the MR hepatobiliary phase was observed in all HCC nodules and in 3 nonmalignant nodules (sensitivity 100%, specificity 70%, positive predictive value 93%, negative predictive value 100%, positive likelihood ratio 3.33, negative likelihood ratio 0). Eight (21%) of the 38 HCC nodules, 7 of which lacked the typical vascular features at any of the imaging modalities, showed washout in the portal/venous phase and hypointensity in the hepatobiliary phase at MRI, while this pattern was not detected in any nonmalignant lesion. Gadoxetic acid magnetic resonance may enhance the sensitivity of the non-invasive diagnosis of small hepatocellular carcinoma nodules in cirrhotic patients under surveillance. Double hypointensity in the portal/venous and hepatobiliary phases could be considered a new magnetic resonance pattern, highly suggestive of hypovascular hepatocellular carcinoma. © 2012 Blackwell Publishing Ltd.

  17. Enhanced refrigerant capacity in Gd-Al-Co microwires with a biphase nanocrystalline/amorphous structure

    Energy Technology Data Exchange (ETDEWEB)

    Shen, H. X. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Department of Physics, University of South Florida, Tampa, Florida 33620 (United States); Xing, D. W.; Liu, Y. F.; Sun, J. F. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Sánchez Llamazares, J. L. [Instituto Potosino de Investigación Científica y Tecnológica A.C., Camino a la Presa San José 2055 Col. Lomas 4a, San Luis Potosí, S.L.P. 78216 (Mexico); Sánchez-Valdés, C. F. [Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, AP 14, Ensenada 22860, Baja California (Mexico); Belliveau, H.; Srikanth, H.; Phan, M. H., E-mail: phanm@usf.edu [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States); Wang, H.; Qin, F. X. [Institute for Composites Science and Innovation (InCSI), College of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

    2016-02-29

    A class of biphase nanocrystalline/amorphous Gd{sub (50+5x)}Al{sub (30−5x)}Co{sub 20} (x = 0, 1, 2) microwires fabricated directly by melt-extraction is reported. High resolution transmission electron microscopy and Fourier function transform based analysis indicate the presence of a volume fraction (∼20%) of ∼10 nm sized nanocrystallities uniformly embedded in an amorphous matrix. The microwires possess excellent magnetocaloric properties, with large values of the isothermal entropy change (−ΔS{sub M} ∼ 9.7 J kg{sup −1} K{sup −1}), the adiabatic temperature change (ΔT{sub ad} ∼ 5.2 K), and the refrigerant capacity (RC ∼ 654 J kg{sup −1}) for a field change of 5 T. The addition of Gd significantly alters T{sub C} while preserving large values of the ΔS{sub M} and RC. The nanocrystallites allow for enhanced RC as well as a broader operating temperature span of a magnetic bed for energy-efficient magnetic refrigeration.

  18. Dynamic contrast-enhanced MRI using a macromolecular MR contrast agent (P792): Evaluation of antivascular drug effect in a rabbit VX2 liver tumor model

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hee Sun [Dept. of Radiology, Konkuk University School of Medicine, Seoul (Korea, Republic of); Han, Joon Koo; Lee, Jeong Min; Woo, Sung Min; Choi, Byung Ihn [Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Young Il [Dept. of Radiology, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah (United Arab Emirates); Choi, Jin Young [Dept. of Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2015-10-15

    To evaluate the utility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using macromolecular contrast agent (P792) for assessment of vascular disrupting drug effect in rabbit VX2 liver tumor models. This study was approved by our Institutional Animal Care and Use Committee. DCE-MRI was performed with 3-T scanner in 13 VX2 liver tumor-bearing rabbits, before, 4 hours after, and 24 hours after administration of vascular disrupting agent (VDA), using gadomelitol (P792, n = 7) or low molecular weight contrast agent (gadoterate meglumine [Gd-DOTA], n = 6). P792 was injected at a of dose 0.05 mmol/kg, while that of Gd-DOTA was 0.2 mmol/kg. DCE-MRI parameters including volume transfer coefficient (Ktrans) and initial area under the gadolinium concentration-time curve until 60 seconds (iAUC) of tumors were compared between the 2 groups at each time point. DCE-MRI parameters were correlated with tumor histopathology. Reproducibility in measurement of DCE-MRI parameters and image quality of source MR were compared between groups. P792 group showed a more prominent decrease in Ktrans and iAUC at 4 hours and 24 hours, as compared to the Gd-DOTA group. Changes in DCE-MRI parameters showed a weak correlation with histologic parameters (necrotic fraction and microvessel density) in both groups. Reproducibility of DCE-MRI parameters and overall image quality was not significantly better in the P792 group, as compared to the Gd-DOTA group. Dynamic contrast-enhanced magnetic resonance imaging using a macromolecular contrast agent shows changes of hepatic perfusion more clearly after administration of the VDA. Gadolinium was required at smaller doses than a low molecular contrast agent.

  19. Dynamic contrast-enhanced MRI using a macromolecular MR contrast agent (P792): Evaluation of antivascular drug effect in a rabbit VX2 liver tumor model

    International Nuclear Information System (INIS)

    Park, Hee Sun; Han, Joon Koo; Lee, Jeong Min; Woo, Sung Min; Choi, Byung Ihn; Kim, Young Il; Choi, Jin Young

    2015-01-01

    To evaluate the utility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using macromolecular contrast agent (P792) for assessment of vascular disrupting drug effect in rabbit VX2 liver tumor models. This study was approved by our Institutional Animal Care and Use Committee. DCE-MRI was performed with 3-T scanner in 13 VX2 liver tumor-bearing rabbits, before, 4 hours after, and 24 hours after administration of vascular disrupting agent (VDA), using gadomelitol (P792, n = 7) or low molecular weight contrast agent (gadoterate meglumine [Gd-DOTA], n = 6). P792 was injected at a of dose 0.05 mmol/kg, while that of Gd-DOTA was 0.2 mmol/kg. DCE-MRI parameters including volume transfer coefficient (Ktrans) and initial area under the gadolinium concentration-time curve until 60 seconds (iAUC) of tumors were compared between the 2 groups at each time point. DCE-MRI parameters were correlated with tumor histopathology. Reproducibility in measurement of DCE-MRI parameters and image quality of source MR were compared between groups. P792 group showed a more prominent decrease in Ktrans and iAUC at 4 hours and 24 hours, as compared to the Gd-DOTA group. Changes in DCE-MRI parameters showed a weak correlation with histologic parameters (necrotic fraction and microvessel density) in both groups. Reproducibility of DCE-MRI parameters and overall image quality was not significantly better in the P792 group, as compared to the Gd-DOTA group. Dynamic contrast-enhanced magnetic resonance imaging using a macromolecular contrast agent shows changes of hepatic perfusion more clearly after administration of the VDA. Gadolinium was required at smaller doses than a low molecular contrast agent

  20. Serial magnetic resonance imaging of acute disseminated encephalomyelitis, including evaluation of the contrast-enhancing effect on lesions by Gd-DTPA

    International Nuclear Information System (INIS)

    Tanaka, Yasunori; Matsuo, Michimasa

    1996-01-01

    Many papers on the MR features of acute disseminated encephalomyelitis (ADEM) have been published, but only a few described contrast-enhanced MRI for this disease. In this study, we analyzed serial changes in MR features and the contrast-enhancing effect on lesions in five patients (5 men, 4-19 years old) discharged with the final diagnosis of ADEM. Hyperintense lesions in brain/spinal cord were demonstrated on T2-weighted MR images in all cases, but not all lesions were enhanced by Gd-DTPA. In the follow-up study many lesions disappeared, but some lesions were enlarged and some new lesions were found. These findings suggest that, although ADEM is clinically monophasic, some cases may progress with the coexistence of reducing, vanishing, and new lesions. Some clinically acute lesions were not enhanced. This might be explained by the following reasons; lesions on various phases coexist, the damage to the blood-brain barrier in the lesions is of different degrees even if it is on the same phase, and the duration of acute phase activity is short. Additionally, some hyperintense lesions remained for a long time on T2-weighted images in spite of the absence of clinical manifestation. That hyperintense area might reflect edema caused by incomplete repair of the blood-brain barrier. From our evaluation of these five cases, MRI is not useful for the diagnosis and follow-up study of ADEM. (author)

  1. 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.

  2. 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.)

  3. Evaluation of Focal Liver Reaction after Proton Beam Therapy for Hepatocellular Carcinoma Examined Using Gd-EOB-DTPA Enhanced Hepatic Magnetic Resonance Imaging.

    Directory of Open Access Journals (Sweden)

    Shigeyuki Takamatsu

    Full Text Available Proton beam therapy (PBT achieves good local control for hepatocellular carcinoma (HCC, and toxicity tends to be lower than for photon radiotherapy. Focal liver parenchymal damage in radiotherapy is described as the focal liver reaction (FLR; the threshold doses (TDs for FLR in the background liver have been analyzed in stereotactic ablative body radiotherapy and brachytherapy. To develop a safer approach for PBT, both TD and liver volume changes are considered clinically important in predicting the extent of damage before treatment, and subsequently in reducing background liver damage. We investigated appearance time, TDs and volume changes regarding FLR after PBT for HCC.Patients who were treated using PBT and were followed up using gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA MRI after PBT were enrolled. Sixty-eight lesions in 58 patients were eligible for analysis. MRI was acquired at the end of treatment, and at 1, 2, 3 and 6 months after PBT. We defined the FLR as a clearly depicted hypointense area on the hepatobiliary phase of Gd-EOB-DTPA MRI, and we monitored TDs and volume changes in the FLR area and the residual liver outside of the FLR area.FLR was depicted in all lesions at 3 months after PBT. In FLR expressed as the 2-Gy equivalent dose (α/β = 3 Gy, TDs did not differ significantly (27.0±6.4 CGE [10 fractions [Fr] vs. 30.5±7.3 CGE [20 Fr]. There were also no correlations between the TDs and clinical factors, and no significant differences between Child-Pugh A and B scores. The volume of the FLR area decreased and the residual liver volume increased, particularly during the initial 3 months.This study established the FLR dose for liver with HCC, which might be useful in the prediction of remnant liver volume for PBT.

  4. Enhanced flux pinning by BaZrO3 and (Gd,y)2O3 nano-structures in metal organic chemical vapor deposited GdYBCO high temperature superconductor tapes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y [SuperPower Incorporated, Schenectady, New York; Selvamanickam, V. [SuperPower Incorporated, Schenectady, New York; Paranthaman, Mariappan Parans [ORNL; Cantoni, Claudia [ORNL; Aytug, Tolga [ORNL; Goyal, Amit [ORNL; Lee, Dominic F [ORNL; Specht, Eliot D [ORNL; Zuev, Yuri L [ORNL; Zhang, Yifei [ORNL

    2009-01-01

    We have formed BaZrO3 nano-columns and (Gd,Y)2O3 nano-precipitates in reel-to-reel MOCVD processed (Gd,Y)Ba2Cu3O7-x coated conductors and increased the critical currents (Ic) of the conductors in applied magnetic fields to remarkable levels. A (Gd,Y)Ba2Cu3O7-x tape of 1m length with 6.5% Zr-additions and 30% composition rich in both Gd and Y showed Ic values of 813 A/cm-width at (self-field, 77K) and above 186 A/cm-width at (1T, 77K). The strongly enhanced flux pinning over a wide range of magnetic field orientations can be attributed to the bidirectionally aligned defect structures of BaZrO3 and (Gd,Y)2O3 created by optimized MOCVD conditions.

  5. 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.

  6. A comprehensive investigation of tetragonal Gd-doped BiVO{sub 4} with enhanced photocatalytic performance under sun-light

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yangyang; Tan, Guoqiang, E-mail: tan3114@163.com; Dong, Guohua; Ren, Huijun; Xia, Ao

    2016-02-28

    Graphical abstract: - Highlights: • Tetragonal Gd-BiVO{sub 4} with enhanced photocatalytic activity was synthesized. • Gd doping can induce the phase transition from monoclinic to tetragonal BiVO{sub 4}. • GdVO{sub 4} seeds as crystal nucleus dominate the formation of tetragonal Gd-BiVO{sub 4}. • Tetragonal Gd-BiVO{sub 4} exhibits the excellent separation of electrons and holes. • The contribution of high photocatalytic activity under sun-light is from UV-light. - Abstract: Tetragonal Gd-doped BiVO{sub 4} having enhanced photocatalytic activity have been synthesized by a facile microwave hydrothermal method. The structural analysis indicates that Gd doping can induce the phase transition from monoclinic to tetragonal BiVO{sub 4}. The reaction results in precursor solutions imply that tetragonal GdVO{sub 4} seeds as crystal nucleus are the original and determined incentives to force the formation of tetragonal Gd-BiVO{sub 4}. The influences of the surface defect, band structure, and BET surface area on the improved photocatalytic activities of tetragonal Gd-doped BiVO{sub 4} are investigated systematically. The results demonstrate that the more surface oxygen deficiencies as active sites and the excellent mobility and separation of photogenerated electrons and holes are beneficial to the enhancement of the photocatalytic performance of tetragonal Gd-BiVO{sub 4}. The RhB photodegradation experiments indicate that the contribution of high photocatalytic activities under simulated sun-light is mainly from UV-light region due to the tetragonal structure feature. The best photocatalytic performance is obtained for tetragonal 10 at% Gd-BiVO{sub 4}, of which the RhB degradation rate can reach to 96% after 120 min simulated sun-light irradiation. The stable tetragonal Gd-BiVO{sub 4} with efficient mineralization will be a promising photocatalytic material applied in water purification.

  7. Assessment of ameloblastomas using MRI and dynamic contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Asaumi, Jun-ichi; Hisatomi, Miki; Yanagi, Yoshinobu; Matsuzaki, Hidenobu; Choi, Yong Suk; Kawai, Noriko; Konouchi, Hironobu; Kishi, Kanji

    2005-01-01

    We retrospectively evaluated magnetic resonance images (MRI) and dynamic contrast-enhanced MRI (DCE-MRI) of ameloblastomas. MRI and DCE-MRI were performed for 10 ameloblastomas. We obtained the following results from the MRI and DCE-MRI. (a) Ameloblastomas can be divided into solid and cystic portions on the basis of MR signal intensities. (b) Ameloblastomas show a predilection for intermediate signal intensity on T1WI, high signal intensity on T2WI, and well enhancement in the solid portion; they also show a homogeneous intermediate signal intensity on T1WI and homogeneous high signal intensity on T2WI, and no enhancement in the cystic portion. (c) The mural nodule or thick wall can be detected in ameloblastomas lesions. (d) CI curves of ameloblastomas show two patterns: the first pattern increases, reaches a plateau at 100-300 s, then sustains the plateau or decreases gradually to 600-900 s, while the other increases relatively rapidly, reaches a plateau at 90-120 s, then decreases relatively rapidly to 300 s, and decreases gradually thereafter. There was no difference in the CI curve patterns among primary and recurrent cases, a case with glandular odontogenic tumor in ameloblastoma or among histopathological types such as plexiform, follicular, mixed, desmoplastic, and unicystic type

  8. Usefulness of T1 mapping on Gd-EOB-DTPA-enhanced MR imaging in assessment of non-alcoholic fatty liver disease

    International Nuclear Information System (INIS)

    Ding, Ying; Rao, Sheng-Xiang; Meng, Tao; Chen, Caizhong; Li, Renchen; Zeng, Meng-Su

    2014-01-01

    This study evaluates the value of Gd-EOB-DTPA-enhanced MRI for diagnosis and staging of non-alcoholic fatty liver disease (NAFLD) in an animal model by T 1 relaxation time measurement. Thirty-four rabbits were divided into the control group (n = 10) and NAFLD group, which was split into four groups (n = 6) with a high-fat diet for an interval of 3 weeks. A dual flip angle was performed before and at the hepatobiliary phase (HBP). T 1 relaxation times of the liver parenchyma and the decrease rate (∇%) were calculated. Histological findings according to semi-quantitative scoring of steatosis, activity and fibrosis were the standard of reference. HBP and ∇% T 1 relaxation time measurement showed significant differences between normal and NAFLD groups, between non-alcoholic steatohepatitis (NASH) and NAFLD without NASH (p = 0.000-0.049), between fibrosis groups (p = 0.000-0.019), but no difference between F1 and F2 (p = 0.834). The areas under the receiver operating characteristic curves (AUCs) of T 1 relaxation time for HBP and ∇% were 0.86-0.93 for the selection of NASH and activity score ≥2, and 0.86-0.95 for the selection of F ≥ 1, 2, 3. No significant difference was found for diagnostic performance between HBP and ∇% T 1 relaxation time. HBP T 1 relaxation time measurement of Gd-EOB-DTPA-enhanced MRI was useful to evaluate NAFLD according to the SAF score. HBP T 1 relaxation time measurement was as accurate as ∇% T 1 relaxation time. (orig.)

  9. Usefulness of T1 mapping on Gd-EOB-DTPA-enhanced MR imaging in assessment of non-alcoholic fatty liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Ying; Rao, Sheng-Xiang; Meng, Tao; Chen, Caizhong; Li, Renchen; Zeng, Meng-Su [Zhongshan/Hospital of Fudan University, Department of Radiology, Shanghai (China)

    2014-04-15

    This study evaluates the value of Gd-EOB-DTPA-enhanced MRI for diagnosis and staging of non-alcoholic fatty liver disease (NAFLD) in an animal model by T{sub 1} relaxation time measurement. Thirty-four rabbits were divided into the control group (n = 10) and NAFLD group, which was split into four groups (n = 6) with a high-fat diet for an interval of 3 weeks. A dual flip angle was performed before and at the hepatobiliary phase (HBP). T{sub 1} relaxation times of the liver parenchyma and the decrease rate (∇%) were calculated. Histological findings according to semi-quantitative scoring of steatosis, activity and fibrosis were the standard of reference. HBP and ∇% T{sub 1} relaxation time measurement showed significant differences between normal and NAFLD groups, between non-alcoholic steatohepatitis (NASH) and NAFLD without NASH (p = 0.000-0.049), between fibrosis groups (p = 0.000-0.019), but no difference between F1 and F2 (p = 0.834). The areas under the receiver operating characteristic curves (AUCs) of T{sub 1} relaxation time for HBP and ∇% were 0.86-0.93 for the selection of NASH and activity score ≥2, and 0.86-0.95 for the selection of F ≥ 1, 2, 3. No significant difference was found for diagnostic performance between HBP and ∇% T{sub 1} relaxation time. HBP T{sub 1} relaxation time measurement of Gd-EOB-DTPA-enhanced MRI was useful to evaluate NAFLD according to the SAF score. HBP T{sub 1} relaxation time measurement was as accurate as ∇% T{sub 1} relaxation time. (orig.)

  10. Assessing liver function in patients with HBV-related HCC: a comparison of T{sub 1} mapping on Gd-EOB-DTPA-enhanced MR imaging with DWI

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Ying; Rao, Sheng-Xiang; Chen, Caizhong; Li, Renchen; Zeng, Meng-Su [Zhongshan Hospital of Fudan University, Department of Radiology, 180 Fenglin Road, Xuhui District, Shanghai (China)

    2015-05-01

    To compare the potential of T{sub 1} mapping on gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) for assessing liver function in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). One hundred consecutive patients with known HBV-related HCCs were included. T{sub 1} relaxation time and apparent diffusion coefficient (ADC) of the liver were measured, and the reduction rate of T{sub 1} relaxation time (∇%) was calculated. T{sub 1} relaxation time measurements were compared with ADC values according to the Model for End-Stage Liver Disease (MELD) score. Hepatobiliary phase (HBP) and ∇% of T{sub 1} relaxation time measurements showed significant correlations with MELD score (rho = 0.571, p < 0.0001; rho = -0.573, p < 0.0001, respectively). HBP and ∇% of T{sub 1} relaxation time were significantly different between good (MELD ≤8) and poor liver function (MELD ≥9) (p < 0.0001 for both). Areas under the receiver operating characteristic curves (AUCs) of T{sub 1} relaxation time for HBP (AUC 0.84) and ∇% (AUC 0.82) were significantly better than for ADC (AUC 0.53; p < 0.0001). T{sub 1} mapping on Gd-EOB-DTPA-enhanced MRI showed promise for evaluating liver function in patients with HBV-related HCC, while DWI was not reliable. HBP T{sub 1} relaxation time measurement was equally accurate as ∇% measurement. (orig.)

  11. Composition-driven enhanced magnetic properties and magnetoelectric coupling in Gd substituted BiFeO{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Vijayasundaram, S.V., E-mail: vijayasundaramsv@gmail.com [Department of Physics, Presidency College, Chennai 600005 (India); Suresh, G. [Department of Physics, Park College of Engineering and Technology, Coimbatore 641659 (India); Department of Urology, Singapore General Hospital, Singapore 169856 (Singapore); Mondal, R.A. [Department of Physics, Hindustan University, Chennai 603103 (India); Kanagadurai, R. [Department of Physics, Presidency College, Chennai 600005 (India)

    2016-11-15

    Bi{sub 1-x}Gd{sub x}FeO{sub 3} (x=0, 0.05 and 0.1) samples were synthesized by modified sol–gel process. X-ray diffraction studies confirmed that the crystal structures of Gd substituted samples remain stable for x<0.1, while compositional-driven structural phase transition from rhombohedral to orthorhombic was observed in the case of x=0.1. The average particle sizes of pure and Gd substituted BiFeO{sub 3} nanoparticles were found to be in the range 62–46 nm. The size of the oblate spherical particles decreased with increasing Gd concentration. XPS studies revealed the trivalent oxidation states of Bi and Fe ions along with sample purity. Pure BiFeO{sub 3} exhibited linear M–H loop indicating its antiferromagnetic characteristics, whereas obvious non-linear M–H loops were observed in Gd substituted samples. In contrast to the observed room temperature magnetization (0.36 emu/g) under 40 kOe for BiFeO{sub 3}, the sample with 10% Gd exhibited appreciable enhancement of magnetization (1.88 emu/g). A leaky type P–E hysteresis loop was observed for the pure one, whereas concave-like ferroelectric loops were obtained for Gd substituted samples. The possible origins of enhanced multiferroic properties have been explained on the basis of substituent, its concentration, phase purity, particle size, structural distortion and the modified magnetic structure. The measurement of magnetoelectric studies at room temperature revealed the coupling between magnetic and ferroelectric ordering, which is desirable for multifunctional device applications of multiferroics. - Highlights: • The substitution of Gd in BiFeO{sub 3} (BFO) nanoparticles led to structural distortion. • Average sizes of the substituted samples are less than the spin period of BFO. • Gd-substitution altered the original magnetic structure of BFO (AFM – FM). • M{sub r} of a substituted sample is an order of magnitude higher than that of BFO. • All the samples show magnetoelectric coupling

  12. Pharmacokinetic analysis of Gd-DTPA enhancement in dynamic MR of breast carcinoma. Pharmakokinetische Analyse der Gd-DTPA-Anreicherung in der MRT beim Mammakarzinom

    Energy Technology Data Exchange (ETDEWEB)

    Hess, T. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Knopp, M.V. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Hoffmann, U. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Brix, G. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Junkermann, H. (Heidelberg Univ. (Germany). Abteilung fuer Gynaekologische Radiologie); Zuna, I. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Fournier, D. von (Heidelberg Univ. (Germany). Abteilung fuer Gynaekologische Radiologie); Kaick, G. van (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie)

    1994-06-01

    Dynamic Gd-DTPA enhanced MR of the breast was performed in one single slice in 27 patients with suspicious nodular lesions. The results could be histologically verified in all cases. A rapid spin-echo sequence with a time resolution of 8.75 s was used for the dynamic examination. The signal changes were analysed using a pharmacokinetic model which allowed parametrization of the contrast enhancement and transformation of the data into colour coded parameter images. The parameters allowed reliable distinction of 9 benign from 18 malignant lesions (p<0.05 for ''amplitude'', p<0.001 for ''k[sub 21]''). One fibroadenoma could not be distinguished from the carcinomas. Lymph node metastases and the pharmacokinetic parameter amplitude correlated significantly (p<0.05). (orig.)

  13. Toxicity evaluation of Gd2O3@SiO2 nanoparticles prepared by laser ablation in liquid as MRI contrast agents in vivo

    Directory of Open Access Journals (Sweden)

    Tian XM

    2014-08-01

    Full Text Available Xiumei Tian,1,* Fanwen Yang,1,* Chuan Yang,2 Ye Peng,1 Dihu Chen,3 Jixiang Zhu,1 Fupo He,1 Li Li,2 Xiaoming Chen11Department of Biomedical Engineering, Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China; 2State Key Laboratory of Oncology in South China, Imaging Diagnosis and Interventional Center, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong Province, People’s Republic of China; 3State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou, Guangdong Province, People’s Republic of China*These authors contributed equally to this workAbstract: Poor toxicity characterization is one obstacle to the clinical deployment of Gd2O3@SiO2 core-shell nanoparticles (Gd-NPs for use as magnetic resonance (MR imaging contrast agents. To date, there is no systematic toxicity data available for Gd-NPs prepared by laser ablation in liquid. In this article, we systematically studied the Gd-NPs’ cytotoxicity, apoptosis in vitro, immunotoxicity, blood circulation half-life, biodistribution and excretion in vivo, as well as pharmacodynamics. The results show the toxicity, and in vivo MR data show that these NPs are a good contrast agent for preclinical applications. No significant differences were found in cell viability, apoptosis, and immunotoxicity between our Gd-NPs and Gd in a DTPA (diethylenetriaminepentaacetic acid chelator. Biodistribution data reveal a greater accumulation of the Gd-NPs in the liver, spleen, lung, and tumor than in the kidney, heart, and brain. Approximately 50% of the Gd is excreted via the hepatobiliary system within 4 weeks. Furthermore, dynamic contrast-enhanced T1-weighted MR images of xenografted murine tumors were obtained after intravenous administration of the Gd-NPs. Collectively, the single step preparation of Gd-NPs by laser ablation in liquid produces particles with satisfactory cytotoxicity

  14. The enhanced activity of mass-selected PtxGd nanoparticles for oxygen electroreduction

    DEFF Research Database (Denmark)

    Velazquez-Palenzuela, Amado Andres; Masini, Federico; Pedersen, Anders Filsøe

    2015-01-01

    Mass-selected platinum–gadolinium alloy nanoparticles (PtxGd NPs) are synthesized for the first time as oxygen reduction reaction (ORR) electrocatalysts using the gas aggregation technique, under ultrahigh vacuum (UHV) conditions. The morphology of the PtxGd catalysts is characterized, and their ......Mass-selected platinum–gadolinium alloy nanoparticles (PtxGd NPs) are synthesized for the first time as oxygen reduction reaction (ORR) electrocatalysts using the gas aggregation technique, under ultrahigh vacuum (UHV) conditions. The morphology of the PtxGd catalysts is characterized...

  15. 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.)

  16. Optimizing signal intensity correction during evaluation of hepatic parenchymal enhancement on gadoxetate disodium-enhanced MRI: Comparison of three methods

    Energy Technology Data Exchange (ETDEWEB)

    Onoda, Minori, E-mail: onoda@radt.med.kindai.ac.jp [Department of Radiological Technology, Kinki University Hospital, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 920-0942 (Japan); Hyodo, Tomoko, E-mail: neneth@m.ehime-u.ac.jp [Department of Radiology, Kinki University Faculty of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Murakami, Takamichi, E-mail: murakami@med.kindai.ac.jp [Department of Radiology, Kinki University Faculty of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Okada, Masahiro, E-mail: okada777@med.u-ryukyu.ac.jp [Department of Radiology, Kinki University Faculty of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Uto, Tatsuro, E-mail: chuho@med.kindai.ac.jp [Department of Radiological Technology, Kinki University Hospital, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Hori, Masatoshi, E-mail: mhori@radiol.med.osaka-u.ac.jp [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Miyati, Tosiaki, E-mail: ramiyati@mhs.mp.kanazawa-u.ac.jp [Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 920-0942 (Japan)

    2015-03-15

    Highlights: •Signal intensity is often used to evaluate hepatic enhancement with Gd-EOB-DTPA in the hepatobiliary phase. •Comparison of uncorrected signal intensity with T{sub 1} value revealed signal intensity instability. •Measurement of uncorrected liver SI or SNR often yields erroneous results on late-phase gadoxetate MRI due to shimming and other optimization techniques. •Signal intensity corrected by scale and rescale slope from DICOM data gave comparable results. -- Abstract: Objective: To compare signal intensity (SI) correction using scale and rescale slopes with SI correction using SIs of spleen and muscle for quantifying multiphase hepatic contrast enhancement with Gd-EOB-DTPA by assessing their correlation with T{sub 1} values generated from Look-Locker turbo-field-echo (LL-TFE) sequence data (ER-T{sub 1}). Materials and methods: Thirty patients underwent Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) in this prospective clinical study. For each patient, breath-hold T{sub 1}-weighted fat-suppressed three-dimensional (3D) gradient echo sequences (e-THRIVE) were acquired before and 2 (first phase), 10 (second phase), and 20 min (third phase) after intravenous Gd-EOB-DTPA. Look-Locker turbo-field-echo (LL-TFE) sequences were acquired before and 1.5 (first phase), 8 (second phase), and 18 min (third phase) postcontrast. The liver parenchyma enhancement ratios (ER) of each phase were calculated using the SI from e-THRIVE sequences (ER-SI) and the T{sub 1} values generated from LL-TFE sequence data (ER-T{sub 1}) respectively. ER-SIs were calculated in three ways: (1) comparing with splenic SI (ER-SI-s), (2) comparing with muscle SI (ER-SI-m), (3) using scale and rescale slopes obtained from DICOM headers (ER-SI-c), to eliminate the effects of receiver gain and scaling. For each of the first, second and third phases, correlation and agreement were assessed between each ER-SI and ER-T{sub 1}. Results: In the first phase, all ER-SIs correlated

  17. MRI enhancing patterns of non-meningioma meningeal lesions

    International Nuclear Information System (INIS)

    Tao Xiaofeng; Ding Juan; Xiao Xiangsheng; Shi Zengru; Yu Hong; Gu Qian

    2004-01-01

    Objective: To analyze the MRI appearances of meningeal diseases and to study MRI diagnostic value of enhancing patterns in different meningeal processes. Methods: Sixty-one patients with integrated clinical data, including 27 infectious meningitis, 4 inflammatory meningitis (2 eosinophilic granuloma, 1 Wegener granuloma, and 1 unknown etiological factor), 12 meningeal metastasis, 2 meningeal lymphoma, 8 cerebrovascular disease, and 8 postoperative changes, were reviewed retrospectively. All patients were examined on MRI before and after contrast administration. Results: (1) MR plain scan: positive findings of plain scan were revealed in only 3 cases, including 1 linear meningeal thickening pattern and 2 nodular pattern. (2) MR enhancement: All cases showed 3 kinds of enhancing patterns: 19 dural-arachnoid pattern, 32 pia-arachnoid pattern, and 10 total meninges pattern, respectively. Conclusion: Different meningeal diseases have different MR imaging manifestations. Creating the enhancement patterns of various diseases can have great clinical significance. (authors)

  18. Distribution patterns of Gd-DTPA-enhanced magnetic resonance imaging after intravenous tissue plasminogen activator therapy for acute myocardial infarction

    International Nuclear Information System (INIS)

    Fukuzawa, Shigeru; Watanabe, Hiroyuki; Shimada, Kazuhiro; Katagiri, Nakoto; Ozawa, Shun

    1994-01-01

    In patients who received thrombolytic therapy for acute myocardial infarction (AMI), we observed 3 distinct patterns in gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA)-enhanced magnetic resonance (MR) imaging. To clarify the significance of these distribution patterns of Gd-DTPA, 20 consecutive patients underwent Gd-DTPA-enhanced MR imaging 7-10 days after AMI. All of the patients received intravenous recombinant tissue plasminogen activator (IVTPA) within 6 h of onset. Echocardiograms were obtained prior to and serially over 10 days, and interpreted for regional wall motion. Coronary angiograms were obtained the day before discharge. None of the 6 patients with a closed infarct-related artery, and 9 of the 14 patients with an open artery, demonstrated subendocardial enhancement (p<0.05). All of these latter 9 patients demonstrated a significant improvement in wall motion between days 1 and 10 after AMI. In contrast, only 1 of the 7 patients with transmural enhancement and none of the 4 patients with non-homogeneous enhancement demonstrated improvement of wall motion on day 10 (p<0.05). We concluded that subendocardial enhancement was a fair prognostic sign for restoration of regional cardiac function in patients who received IVTPA during AMI. (author)

  19. Chronological observation in early radiation myelopathy of the cervical spinal cord; Gadolinium-enhanced MRI findings in two cases

    Energy Technology Data Exchange (ETDEWEB)

    Hirota, Saeko; Yoshida, Shoji; Soejima, Toshinori (Hyogo Medical Center for Adults, Akashi (Japan)) (and others)

    Gd-enhanced MR images of two patients with clinically and histopathologically diagnosed chronic progressive radiation myelitis (CPRM) were observed chronologically. One of them had had nasopharyngeal cancer and received radiotherapy at a dose of 100 Gy to the C1-2 level of the spinal cord. She developed CPRM 25 months after the termination of radiotherapy. The other had had malignant lymphoma originating from the tonsil and received chemoradiotherapy. The dose delivered to her cervical spinal cord was 40 Gy, and she developed CPRM 30 months later. Gd-enhanced MRI in the early phase revealed a small crescent-shaped nidus with or without a very small central nonenhanced area in both cases. Enhancement was not great. At that time, patients noticed only the inability to perceive pain and temperature or paresthesia in the opposite side. In a few months, MRI revealed a much more strongly enhanced and larger nidus with enlargement of a central nonenhanced area accompanied by long segmental cord enlargement. The patients' neurological symptoms had also progressed, with hemiparesis developing, for example. (author).

  20. Giant cisterna chyli: MRI depiction with gadolinium-DTPA enhancement

    International Nuclear Information System (INIS)

    Lee, K.C.Y.; Cassar-Pullicino, V.N.

    2000-01-01

    AIM: To demonstrate the use of MRI with Gadolinium-DTPA enhancement in the diagnosis of giant cisterna chyli. MATERIALS AND METHODS: The study consisted of contrast enhanced MRI with ultrasound and CT correlation in three patients with a giant cisterna chyli. An analysis of the morphology, location and post-contrast MR signal characteristics in relation to time was performed. RESULTS: Cisterna chyli has a characteristic lobulated morphology and location but the unenhanced MRI appearances are not specific. The post-Gadolinium-DTPA MRI appearances are critically dependent on the time elapsed after injection of contrast medium. Within the first 5 min, there is no enhancement at all, but by 10 min there is early layering of contrast medium evident, which by 30 min produces a clear fluid-fluid level. Delayed images at 4-5 h demonstrate a uniform enhancement of the cisternal contents producing a homogeneous intermediate signal. All of these features are best visualized on T1 fast saturation sequences. CONCLUSION: MRI with Gadolinium-DTPA enhancement is valuable in confirming the nature of the lymphatic ducts in the retroperitoneal space and helps to differentiate these normal structures from alternative lesions such as lymphadenopathy and tumour recurrence. Lee, K.C.Y., Cassar-Pullicino, V.N. (2000)

  1. Serial assessment of the area at risk in myocardial infarction with Gd-DTPA-enhanced MR imaging in humans

    International Nuclear Information System (INIS)

    de Roos, A.; Doornbos, J.; Matheijssen, N.; van Dijkman, P.; van der Wall, E.; van Voorthuisen, A.E.

    1989-01-01

    Experimental studies have shown that the region of increased myocardial signal intensity with Gd-DTPA correlates with the area at risk but overestimates the infarct size. The authors have assessed the evolution of the area at risk in acute myocardial infarction in seven patients, using Gd-DTPA enhanced MR imaging at 1 and 2 weeks after the acute event. Multisection MR imaging of the total left ventricle was performed at 0.5 T after injection of 0.2 mmol/kg of Gd-DTPA. The area with a signal intensity greater than that of normal myocardium (± 2SDs) was designated as the area at risk in each section. The summation of these areas was measured by two observers at 1 and 2 weeks after infarction; intra- and interobserver variability was 3%. The area at risk ranged from 3% to 18%; at 2 weeks the size of the area at risk showed only slight changes (P = not significant). The authors discuss how Gd- DTPA enhances the area at risk and may be useful in assessing the evolution of the size of this area

  2. In vivo immunotoxicity evaluation of Gd2O3 nanoprobes prepared by laser ablation in liquid for MRI preclinical applications

    Science.gov (United States)

    Tian, Xiumei; Guan, Xiaoying; Luo, Ningqi; Yang, Fanwen; Chen, Dihu; Peng, Ye; Zhu, Jixiang; He, Fupo; Li, Li; Chen, Xiaoming

    2014-09-01

    Gd2O3 nanoprobes prepared by laser ablation in liquid can be used as magnetic resonance imaging contrast agent. However, their immunotoxicity in vivo remains unknown. In this article, the in vitro biocompatibility of the Gd2O3 nanoprobe was evaluated in terms of cell uptake, cell viability, and apoptosis. In vivo immunotoxicity was detected by monitoring the levels of the immunity mediator, cluster of differentiation (CD) markers in Balb/c mice. The results show that no in vitro cytotoxicity was observed, and no significant changes in the expression levels of CD206 and CD69 between the nanoprobe-injected group and the Gd-DTPA group in mice were observed. Importantly, the immunotoxicity data revealed significant differences in the expression levels of CD40, CD80, CD11b, and reactive oxygen species. In addition, transmission electron microscopy images showed that few Gd2O3 nanoprobes were localized in phagosomes by the endocytic pathway. In conclusion, the toxic effects of our Gd2O3 nanoprobe may be due to endocytosis during which the microstructure or ultrastructure of cells is slightly damaged and induces the generation of an oxidative stress reaction that further stimulates the innate immune response. Therefore, it is important to use a sensitive assay for the in vivo immunotoxicity measurements to evaluate the risk assessment of Gd2O3-based biomaterials at the molecular level.

  3. Contrast enhancement of the cerebrospinal fluid on MRI in two cases of spirochaetal meningitis

    International Nuclear Information System (INIS)

    Good, C.D.; Jaeger, H.R.

    2000-01-01

    We report two patients with meningitis due to spirochaetal infection, both of whom showed diffusely enhancing meninges around the brain and spinal cord. In addition, there was enhancement of the cerebrospinal fluid after intravenous administration of Gd-DTPA. (orig.)

  4. Enhanced Photocatalytic Activity of Rare Earth Metal (Nd and Gd doped ZnO Nanostructures

    Directory of Open Access Journals (Sweden)

    P. Logamani

    2017-06-01

    Full Text Available Presence of harmful organic pollutants in wastewater effluents causes serious environmental problems and therefore purification of this contaminated water by a cost effective treatment method is one of the most important issue which is in urgent need of scientific research. One such promising treatment technique uses semiconductor photocatalyst for the reduction of recalcitrant pollutants in water. In the present work, rare earth metals (Nd and Gd doped ZnO nanostructured photocatalyst have been synthesized by wet chemical method. The prepared samples were characterized by X-ray diffraction (XRD, Field Emission Scanning Electron Microscopy (FESEM and energy dispersive X-ray spectroscopy (EDS. The XRD results showed that the prepared samples were well crystalline with hexagonal Wurtzite structure. The results of EDS revealed that rare earth elements were doped into ZnO structure. The effect of rare earth dopant on morphology and photocatalytic degradation properties of the prepared samples were studied and discussed. The results revealed that the rare earth metal doped ZnO samples showed enhanced visible light photocatalytic activity for the degradation of methylene blue dye than pure nano ZnO photocatalyst.

  5. Pharmacokinetic parameters derived from dynamic contrast enhanced MRI of cervical cancers predict chemoradiotherapy outcome

    International Nuclear Information System (INIS)

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

    2013-01-01

    Purpose: To assess the prognostic value of pharmacokinetic parameters derived from pre-chemoradiotherapy dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) of cervical cancer patients. Materials and methods: Seventy-eight patients with locally advanced cervical cancer underwent DCE-MRI with Gd-DTPA before chemoradiotherapy. The pharmacokinetic Brix and Tofts models were fitted to contrast enhancement curves in all tumor voxels, providing histograms of several pharmacokinetic parameters (Brix: A Brix , k ep , k el , Tofts: K trans , ν e ). A percentile screening approach including log-rank survival tests was undertaken to identify the clinically most relevant part of the intratumoral parameter distribution. Clinical endpoints were progression-free survival (PFS) and locoregional control (LRC). Multivariate analysis including FIGO stage and tumor volume was used to assess the prognostic significance of the imaging parameters. Results: A Brix , k el , and K trans were significantly (P e was significantly positively correlated with PFS only. k ep showed no association with any endpoint. A Brix was positively correlated with K trans and ν e , and showed the strongest association with endpoint in the log-rank testing. k el and K trans were independent prognostic factors in multivariate analysis with LRC as endpoint. Conclusions: Parameters estimated by pharmacokinetic analysis of DCE-MR images obtained prior to chemoradiotherapy may be used for identifying patients at risk of treatment failure

  6. Cerebral and meningeal manifestations of AIDS: comparison of plain T2-weighted images and Gd-DTPA enhanced T1-weighted images in 105 patients

    International Nuclear Information System (INIS)

    Jochens, R.; Henkes, H.; Steinkamp, H.J.; Terstegge, K.; Hosten, N.; Ruf, B.; Schoerner, W.

    1994-01-01

    The purpose of the present study was to evaluate the potential of T1-weighted Gd-DTPA enhanced MR imaging in the diagnosis of cerebral manifestations of AIDS. 105 patients with AIDS were imaged with plain T2-weighted images as well as with Gd-DTPA enhanced T1-weighted pulse sequences. Our study revealed comparable sensitivities in the detection of morphological changes as shown on plain T2-weighted images and Gd-DTPA enhanced T1-weighted images in 55% of patients (normal and pathologic findings). Plain T2-weighted images were superior in 28.5% and provided significantly better results in 8.5% of patients. Gd-DTPA enhanced T1-weighted images were superior in only 5% cases and revealed significantly better results in 3%. As a result, T2-weighted plain images were superior in approximately 40% of patients concerning detection of morphologic changes. In almost 10% of patients with parechymal and meningeal lesions, Gd-DTPA enhanced T1-weighted images, however, were superior or even significantly better compared to T2-weighted plain images. The detection of morphologic changes in MR imaging can be further increased with Gd-DTPA. With regard to differential diagnosis and diesease activity, plain T2-weighted images and Gd-DTPA enhanced T1-weighted images revealed comparable results in 42% of patients (normal and pathologic findings). T2-weighted plain images were superior in 2% of cases whereas Gd-DTPA enhanced T1-weighted images were superior in as much as 56% of patient. MR imaging enhanced with Gd-DTPA yielded additional information on disease activity in 73% of patients with pathologic findings in the cerebral parechyma and the meninges. The surplus of information also refers to the etiology of cerebral pathology and differential diagnosis. Because of the frequency of cerebral manifestations in AIDS, early diagnosis for initiation of therapy and follow-up studies to monitor therapy are crucial. (orig./MG) [de

  7. 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

  8. 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.

  9. Sequential gadolinium-DTPA enhanced MRI studies in neuro-Behcet's disease

    International Nuclear Information System (INIS)

    Kazui, S.; Naritomi, H.; Ogawa, M.; Sawada, T.; Imakita, S.; Yamada, N.

    1991-01-01

    Sequential gadolinium-DTPA (Gd-DTPA) enhanced MR images were obtained before and after steroid therapy in a case of neuro-Behcet's disease. Multiple scattered lesions, which could not be detected on pre- and post-contrast CT, were demonstrated mainly in the white matter of the pons and/or the cerebrum with both T1- and T2-weighted images. Some of these lesions, however, were not enhanced at all by infusion of Gd-DTPA. The Gd-DTPA infusion study demonstrated marked enhancement in the white matter of the pons and cerebrum. Some lesions not seen with T2-weighted images were also strongly enhanced by Gd-DTPA infusion at the acute stage. After steroid therapy, the symptoms and abnormal laboratory findings were resolved. The pontine and cerebral lesions on plain MR images remained unchanged even after resolution of the symptoms, suggesting that they were inactive old foci. On the other hand, the lesions detected in the enhancement study before steroid therapy disappeared with the repeat Gd-DTPA enhanced MR images which were performed after resolution of the symptoms. Some active inflammatory lesions in neuro-Behcet's disease may be demonstrated only on Gd-DTPA enhanced MR images. Gd-DTPA enhanced MR imaging appears to be potentially useful for detecting active inflammatory lesions in neuro-Behcet's disease and for evaluating the efficacy of treatment. (orig.)

  10. Enhanced glass forming ability and refrigerant capacity of a Gd55Ni22Mn3Al20 bulk metallic glass

    International Nuclear Information System (INIS)

    Xia, L.; Chan, K.C.; Tang, M.B.

    2011-01-01

    Highlights: → A new Gd 55 Ni 22 Mn 3 Al 20 bulk metallic glass (BMG) was synthesized by minor Mn addition. → The BMG has enhanced glass forming ability and excellent refrigerant capacity (RC). → The RC of the BMG reaches a high value of 825 J kg -1 under a field of 3979 kA/m. → Its excellent RC is related to its large effective magnetic moment. - Abstract: In this work, a small amount of Mn was added to a Gd 55 Ni 25 Al 20 glass forming alloy, as a replacement for Ni, and a Gd 55 Ni 22 Mn 3 Al 20 bulk metallic glass (BMG) was obtained by suction casting. Its glass forming ability (GFA) was characterized by X-ray diffraction and differential scanning calorimetry, and its magnetic properties were measured using a magnetic property measurement system. It is found that the minor Mn addition can significantly improve both the GFA and the magnetocaloric effect (MCE) of the alloy. The refrigerant capacity (RC) of the BMG can reach a high value of 825 J kg -1 under a field of 3979 kA/m, which is about 29% larger than that of a Gd 55 Ni 25 Al 20 BMG. The effect of the minor Mn addition on the GFA and MCE of the BMG was investigated in the study.

  11. Pr and Gd co-doped bismuth ferrite thin films with enhanced

    Indian Academy of Sciences (India)

    Pr and Gd co-modified Bi0.95−PrGd0.05FeO3 ( = 0.00, 0.05, 0.10) (BPGFO) thin films on Pt(111)/Ti/SiO2/Si(100) substrates were prepared by a sol-gel together with spin coating technique. A detailed study of electrical and magnetic properties of these thin films is reported. X-ray diffraction analysis shows that, with an ...

  12. 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

  13. MRI

    DEFF Research Database (Denmark)

    Schroeter, Aileen; Rudin, Markus; Gianolio, Eliana

    2017-01-01

    This chapter discusses principles of nuclear magnetic resonance (NMR) and MRI followed by a survey on the major classes of MRI contrast agents (CA), their modes of action, and some of the most significative applications. The two more established classes of MRI-CA are represented by paramagnetic...... been attained that markedly increase the number and typology of systems with CEST properties. Currently much attention is also devoted to hyperpolarized molecules that display a sensitivity enhancement sufficient for their direct exploitation for the formation of the MR image. A real breakthrough...

  14. Marginal erosive discovertebral ''Romanus'' lesions in ankylosing spondylitis demonstrated by contrast enhanced Gd-DTPA magnetic resonance imaging

    International Nuclear Information System (INIS)

    Jevtic, V.; Kos-Golja, M.; Rozman, B.; McCall, I.

    2000-01-01

    Objective. To assess the value of Gd-DTPA magnetic resonance (MR) imaging in the demonstration of marginal destructive discovertebral Romanus lesions in ankylosing spondylitis.Design and patients. A prospective study of Gd-DTPA MR imaging was performed in 39 patients with a clinical diagnosis of ankylosing spondylitis and typical Romanus lesions seen on radiographs of the thoracolumbar spine. MR morphological appearances and signal intensity changes at the discovertebral junctions were analysed and compared with the radiographic findings.Results. Ninety-nine discovertebral junctions with Romanus lesions showed low signal intensity on T1-weighted and high signal on T2-weighted and T1-weighted postcontrast images at the vertebral corners consistent with oedematous hyperaemic inflammatory tissue. There were nine discovertebral junctions with similar MR findings but normal radiographs. Fifty-three discovertebral junctions showed syndesmophyte formation with increased signal intensity on both T1- and T2-weighted images with no contrast enhancement. Sixty-five discovertebral junctions showed a mixture of radiographic features and varied high and low signal changes at the vertebral rim on MR imaging with rims of enhancement in the vertebral body following contrast administration.Conclusion. Gd-DTPA MR imaging demonstrates a variable signal pattern and degree of contrast enhancement which may reflect the evolutionary stages of discovertebral enthesitis in ankylosing spondylitis. MR imaging may identify early erosive changes in radiographically normal vertebra. The role of MR imaging needs further investigation. (orig.)

  15. Is enhanced MRI helpful in brainstem infarction?

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. M.; Shin, G. H.; Choi, W. S. [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1994-12-15

    To determine the role of MR contrast enhancement in evaluating time course of brainstem infarction. MR imaging with IV administration of gadopentetate dimeglumine was retrospectively reviewed in 43 patients with clinically and radiologically documented brainstem infarctions. The pattern of infarction was classified into spotty and patchy. Presence of parenchymal enhancement in infarction was evaluated. By location, there were 34 pontine, 3 midbrain, 6 medullary infarctions. The age of the infarctions ranged from 1 day to 9 months, with 5 patients scanned within 3 days and 10 scanned within 2 weeks of clinical ictus. Abnormalities on T2-weighted images were encountered in every case, with spotty pattern in 14 cases and patchy pattern in 29 cases. Parenchymal contrast enhancement was seen in 9 cases(20%), primarily occurring between days 8 and 20. MR contrast enhancement in brainstem infarction was infrequent that it may not be useful in the estimation of the age of infarction.

  16. Evaluation of a gadolinium-based nanoparticle (AGuIX) for contrast-enhanced MRI of the liver in a rat model of hepatic colorectal cancer metastases at 9.4 tesla

    Energy Technology Data Exchange (ETDEWEB)

    Fries, P.; Morr, D.; Mueller, A.; Massmann, A.; Seidel, R.; Schneider, G.; Buecker, A. [Saarland University Medical Center, Homburg (Germany). Clinic of Diagnostic and Interventional Radiology; Lux, F.; Tillement, O. [Universite Claude Bernard, Lyon (France). Laboratoire de Physico-Chimie des Materiaux Luminescents; Schaefer, T. [Saarland University Medical Center, Homburg (Germany). Dept. of General, Visceral and Pediatric Surgery; Menger, M.D. [Saarland University Medical Center, Homburg (Germany). Inst. for Clinical and Experimental Surgery

    2015-12-15

    The aim of this study was to compare a Gd-based nanoparticle (AGuIX) with a standard extracellular Gd-based contrast agent (Gd-DOTA) for MRI at 9.4 T in rats with hepatic colorectal cancer metastases. 12 rats with hepatic metastases were subjected to MRI using a 9.4 T animal scanner. T1w self-gated FLASH sequences (TR/TE=45/2.5 ms, alpha = 45 , TA=1: 23 min, FOV=5.12 x 5.12 cm{sup 2}, matrix = 256 x 256) were acquired before and at 10 time points after contrast injection. Each animal received 0.1 mmol/kg BW Gd-DOTA i.v. 2 days later AGuIX was applied at 0.01 mmol/kg BW (representing equal Gd doses). The SNR of normal liver (SNRliver), hyper- and hypoenhancing parts of tumors (SNRtumor, hyperenh/SNRtumor, hypoenhanc), erector spinae muscle (SNRmuscle), CNR and lesion enhancement (LE) were calculated based on ROI measurements. Mean SNRliver (Gd-DOTA: 14.6 ± 0.7; AGuIX: 28.2 ± 2.6, p < 0.001), SNRtumor, hyperenhanc (Gd-DOTA: 18.6 ± 1.2; AGuIX: 29.6 ± 2.8, p < 0.001), SNRtumor, hypoenhanc (Gd-DOTA: 12.0 ± 0.7; AGuIX: 15.4 ± 0.7, p < 0.001), SNRmuscle (Gd-DOTA: 12.3 ± 0.3; AGuIX: 14.0 ± 0.7, p < 0.001), mean CNR (Gd-DOTA: -2.5 ± 0.2; AGuIX: -7.5 ± 1.0, p < 0.001) and LE (Gd-DOTA: 3.8 ± 0.7; AGuIX: 14.9 ± 2.8, p=0.001) were significantly higher using AGuIX. Regardless of the larger molecular size, AGuIX demonstrates an early peak enhancement followed by a continuous washout. AGuIX provides better enhancement at 9.4 T compared to Gd-DOTA for equal doses of applied Gd. This is based on the molecule structure and the subsequent increased interaction with protons leading to a higher relaxivity. AGuIX potentially ameliorates the conspicuity of focal liver lesions and may improve the sensitivity in diagnostic imaging of malignant hepatic tumors.

  17. Evaluation of a gadolinium-based nanoparticle (AGuIX) for contrast-enhanced MRI of the liver in a rat model of hepatic colorectal cancer metastases at 9.4 tesla

    International Nuclear Information System (INIS)

    Fries, P.; Morr, D.; Mueller, A.; Massmann, A.; Seidel, R.; Schneider, G.; Buecker, A.; Lux, F.; Tillement, O.; Schaefer, T.; Menger, M.D.

    2015-01-01

    The aim of this study was to compare a Gd-based nanoparticle (AGuIX) with a standard extracellular Gd-based contrast agent (Gd-DOTA) for MRI at 9.4 T in rats with hepatic colorectal cancer metastases. 12 rats with hepatic metastases were subjected to MRI using a 9.4 T animal scanner. T1w self-gated FLASH sequences (TR/TE=45/2.5 ms, alpha = 45 , TA=1: 23 min, FOV=5.12 x 5.12 cm 2 , matrix = 256 x 256) were acquired before and at 10 time points after contrast injection. Each animal received 0.1 mmol/kg BW Gd-DOTA i.v. 2 days later AGuIX was applied at 0.01 mmol/kg BW (representing equal Gd doses). The SNR of normal liver (SNRliver), hyper- and hypoenhancing parts of tumors (SNRtumor, hyperenh/SNRtumor, hypoenhanc), erector spinae muscle (SNRmuscle), CNR and lesion enhancement (LE) were calculated based on ROI measurements. Mean SNRliver (Gd-DOTA: 14.6 ± 0.7; AGuIX: 28.2 ± 2.6, p < 0.001), SNRtumor, hyperenhanc (Gd-DOTA: 18.6 ± 1.2; AGuIX: 29.6 ± 2.8, p < 0.001), SNRtumor, hypoenhanc (Gd-DOTA: 12.0 ± 0.7; AGuIX: 15.4 ± 0.7, p < 0.001), SNRmuscle (Gd-DOTA: 12.3 ± 0.3; AGuIX: 14.0 ± 0.7, p < 0.001), mean CNR (Gd-DOTA: -2.5 ± 0.2; AGuIX: -7.5 ± 1.0, p < 0.001) and LE (Gd-DOTA: 3.8 ± 0.7; AGuIX: 14.9 ± 2.8, p=0.001) were significantly higher using AGuIX. Regardless of the larger molecular size, AGuIX demonstrates an early peak enhancement followed by a continuous washout. AGuIX provides better enhancement at 9.4 T compared to Gd-DOTA for equal doses of applied Gd. This is based on the molecule structure and the subsequent increased interaction with protons leading to a higher relaxivity. AGuIX potentially ameliorates the conspicuity of focal liver lesions and may improve the sensitivity in diagnostic imaging of malignant hepatic tumors.

  18. Postoperative meningeal enhancement on MRI in children with brain neoplasms

    International Nuclear Information System (INIS)

    Lee, Min Hee; Han, Bokyung Kim; Yoon, Hye Kyung; Shin, Hyung Jin

    2000-01-01

    The meninges composed of the dura, the arachnoid and the pia are significant sites of blood-brain barrier. Physical disruption of the integrity of the meninges from a variety of causes including surgery results in various patterns of meningeal enhancement on contrast enhanced MR images. It is important to distinguish normal reactive or benign postoperative enhancement from more serious leptomeningeal metastasis or infection, particularly in children with intracranial neoplasms. We present various patterns of meningeal enhancement on MRI in children following surgery for brain neoplasms. (author)

  19. Rotational dynamics account for pH-dependent relaxivities of PAMAM dendrimeric, Gd-based potential MRI contrast agents.

    Science.gov (United States)

    Laus, Sabrina; Sour, Angélique; Ruloff, Robert; Tóth, Eva; Merbach, André E

    2005-05-06

    The EPTPA5) chelate, which ensures fast water exchange in GdIII complexes, has been coupled to three different generations (5, 7, and 9) of polyamidoamine (PAMAM) dendrimers through benzylthiourea linkages (H5EPTPA = ethylenepropylenetriamine-N,N,N',N'',N''-pentaacetic acid). The proton relaxivities measured at pH 7.4 for the dendrimer complexes G5-(GdEPTPA)111, G7-(GdEPTPA)253 and G9-(GdEPTPA)1157 decrease with increasing temperature, indicating that, for the first time for dendrimers, slow water exchange does not limit relaxivity. At a given field and temperature, the relaxivity increases from G5 to G7, and then slightly decreases for G9 (r1 = 20.5, 28.3 and 27.9 mM(-1) s(-1), respectively, at 37 degrees C, 30 MHz). The relaxivities show a strong and reversible pH dependency for all three dendrimer complexes. This originates from the pH-dependent rotational dynamics of the dendrimer skeleton, which was evidenced by a combined variable-temperature and multiple-field 17O NMR and 1H relaxivity study performed at pH 6.0 and 9.9 on G5-(GdEPTPA)111. The longitudinal 17O and 1H relaxation rates of the dendrimeric complex are strongly pH-dependent, whereas they are not for the [Gd(EPTPA)(H2O)]2- monomer chelate. The longitudinal 17O and 1H relaxation rates have been analysed by the Lipari-Szabo spectral density functions and correlation times have been calculated for the global motion of the entire macromolecule (tau(gO)) and the local motion of the GdIII chelates on the surface (tau(lO)), correlated by means of an order parameter S2. The dendrimer complex G5-(GdEPTPA)111 has a considerably higher tau(gO) under acidic than under basic conditions (tau(298)gO = 4040 ps and 2950 ps, respectively), while local motions are less influenced by pH (tau(298)lO = 150 and 125 ps). The order parameter, characterizing the rigidity of the macromolecule, is also higher at pH 6.0 than at pH 9.9 (S2 = 0.43 vs 0.36, respectively). The pH dependence of the global correlation time can be

  20. Elemental imaging of MRI contrast agents: benchmarking of LA-ICP-MS to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Pugh, J.A.T. [University of Sheffield, Centre for Analytical Sciences, Sheffield (United Kingdom); University of Sheffield, Department of Chemical and Biological Engineering, Sheffield (United Kingdom); Cox, A.G.; McLeod, C.W. [University of Sheffield, Centre for Analytical Sciences, Sheffield (United Kingdom); Bunch, J. [University of Birmingham, School of Chemistry, Birmingham (United Kingdom); Writer, M.J.; Hart, S.L. [UCL Institute of Child Health, Wolfson Centre for Gene Therapy of Childhood Disease, London (United Kingdom); Bienemann, A.; White, E. [University of Bristol, School of Clinical Sciences, Southmead Hospital, Bristol (United Kingdom); Bell, J. [Hammersmith Hospital, Metabolic and Molecular Imaging Group, MRC Clinical Sciences Centre, Imperial College London, London (United Kingdom)

    2012-06-15

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been used to map the spatial distribution of magnetic resonance imaging (MRI) contrast agents (Gd-based) in histological sections in order to explore synergies with in vivo MRI. Images from respective techniques are presented for two separate studies namely (1) convection enhanced delivery of a Gd nanocomplex (developmental therapeutic) into rat brain and (2) convection enhanced delivery, with co-infusion of Magnevist (commercial Gd contrast agent) and Carboplatin (chemotherapy drug), into pig brain. The LA technique was shown to be a powerful compliment to MRI not only in offering improved sensitivity, spatial resolution and signal quantitation but also in giving added value regarding the fate of administered agents (Gd and Pt agents). Furthermore simultaneous measurement of Fe enabled assignment of an anomalous contrast enhancement region in rat brain to haemorrhage at the infusion site. (orig.)

  1. Accumulation of MRI contrast agents in malignant fibrous histiocytoma for gadolinium neutron capture therapy

    International Nuclear Information System (INIS)

    Fujimoto, T.; Ichikawa, H.; Akisue, T.; Fujita, I.; Kishimoto, K.; Hara, H.; Imabori, M.; Kawamitsu, H.; Sharma, P.; Brown, S.C.; Moudgil, B.M.; Fujii, M.; Yamamoto, T.; Kurosaka, M.; Fukumori, Y.

    2009-01-01

    Neutron-capture therapy with gadolinium (Gd-NCT) has therapeutic potential, especially that gadolinium is generally used as a contrast medium in magnetic resonance imaging (MRI). The accumulation of gadolinium in a human sarcoma cell line, malignant fibrosis histiocytoma (MFH) Nara-H, was visualized by the MRI system. The commercially available MRI contrast medium Gd-DTPA (Magnevist, dimeglumine gadopentetate aqueous solution) and the biodegradable and highly gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles (Gd-nanoCPs) were prepared as MRI contrast agents. The MFH cells were cultured and collected into three falcon tubes that were set into the 3-tesra MRI system to acquire signal intensities from each pellet by the spin echo method, and the longitudinal relaxation time (T1) was calculated. The amount of Gd in the sample was measured by inductively coupled plasma atomic emission spectrography (ICP-AES). The accumulation of gadolinium in cells treated with Gd-nanoCPs was larger than that in cells treated with Gd-DTPA. In contrast, and compared with the control, Gd-DTPA was more effective than Gd-nanoCPs in reducing T1, suggesting that the larger accumulation exerted the adverse effect of lowering the enhancement of MRI. Further studies are warranted to gain insight into the therapeutic potential of Gd-NCT.

  2. 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.

  3. 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.

  4. Dynamic enhanced MRI of the subacromial bursa: correlation with arthroscopic and histological findings

    International Nuclear Information System (INIS)

    Matsuzaki, S.; Yoneda, M.; Kobayashi, Y.; Fukushima, S.; Wakitani, S.

    2003-01-01

    Objective: To assess dynamic MRI with Gd-DTPA enhancement for evaluating inflammatory changes in the subacromial bursa. Design and patients: We detected the signal intensity changes in dynamic MRI of the subacromial bursa, and confirmed these macroscopically by arthroscopy and histologically. The signal intensity was measured using built-in software, and the enhancement ratio (E ratio) was calculated from dynamic MR images. In addition, as a parameter of the rate of the increase in the signal intensity from 0 to 80 s, the mean increase per second in the E ratio was obtained as the coefficient of enhancement (CE). The correlation was studied of the E ratio and CE with the arthroscopic findings (redness, villous formation, thickening and adhesion), and of the E ratio and CE with the histological findings (capillary proliferation, papillary hyperplasia, fibrosis and inflammatory cell infiltration) of the subacromial bursa. Of patients with shoulder pain, this study included those with rotator cuff injury; patients with rheumatoid arthritis or pitching shoulder disorders were excluded. There were 27 patients (15 men, 12 women) ranging in age from 25 to 73 years (mean 49.1 years). Dynamic MRI of the shoulder was also performed on the healthy side of 10 patients and in five normal young volunteers. Results and conclusions: Changes in signal intensity on dynamic MRI were measured in the subacromial bursa. The E ratio (80 s) and CE (0-80 s) were significantly correlated with redness and villous formation as arthroscopic findings, positively correlated with capillary proliferation and papillary hyperplasia as histological findings (p < 0.05), and negatively correlated with fibrosis as a histological finding (p < 0.05) in the subacromial bursa. The patterns of dynamic curves were well correlated with the bursoscopic and histological findings of the synovium of the subacromial bursa. Dynamic MRI appears to correlate with inflammatory activity of synovium of the subacromial

  5. Intraindividual comparison of T1 relaxation times after gadobutrol and Gd-DTPA administration for cardiac late enhancement imaging

    Energy Technology Data Exchange (ETDEWEB)

    Doeblin, Patrick, E-mail: Patrick.doeblin@charite.de [Department of Cardiology, Charité – Universitätsmedizin Berlin, Charité Campus Benjamin Franklin, Berlin (Germany); Schilling, Rene, E-mail: rene.schilling@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Wagner, Moritz, E-mail: moritz.wagner@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Luhur, Reny, E-mail: renyluhur@yahoo.com [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Huppertz, Alexander, E-mail: alexander.huppertz@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Imaging Science Institute, Charité, Berlin (Germany); Hamm, Bernd, E-mail: bernd.hamm@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Taupitz, Matthias, E-mail: matthias.taupitz@harite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); and others

    2014-04-15

    Purpose: To evaluate T1-relaxation times of chronic myocardial infarction (CMI) using gadobutrol and gadopentetate dimeglumine (Gd-DTPA) over time and to determine the optimal imaging window for late enhancement imaging with both contrast agents. Material and methods: Twelve patients with CMI were prospectively included and examined on a 1.5 T magnetic resonance (MR) system using relaxivity-adjusted doses of gadobutrol (0.15 mmol/kg) and Gd-DTPA (0.2 mmol/kg) in random order. T1-relaxation times of remote myocardium (RM), infarcted myocardium (IM), and left ventricular cavity (LVC) were assessed from short-axis TI scout imaging using the Look–Locker approach and compared intraindividually using a Wilcoxon paired signed-rank test (α < 0.05). Results: Within 3 min of contrast agent administration (CA), IM showed significantly lower T1-relaxation times than RM with both contrast agents, indicating beginning cardiac late enhancement. Differences between gadobutrol and Gd-DTPA in T1-relaxation times of IM and RM were statistically not significant through all time points. However, gadobutrol led to significantly higher T1-relaxation times of LVC than Gd-DTPA from 6 to 9 min (220 ± 15 ms vs. 195 ± 30 ms p < 0.01) onwards, resulting in a significantly greater ΔT1 of IM to LVC at 9–12 min (−20 ± 35 ms vs. 0 ± 35 ms, p < 0.05) and 12–15 min (−25 ± 45 ms vs. −10 ± 60 ms, p < 0.05). Using Gd-DTPA, comparable ΔT1 values were reached only after 25–35 min. Conclusion: This study indicates good delineation of IM to RM with both contrast agents as early as 3 min after administration. However, we found significant differences in T1 relaxation times with greater ΔT1 IM–LVC using 0.15 mmol/kg gadobutrol compared to 0.20 mmol/kg Gd-DTPA after 9–15 min post-CA suggesting earlier differentiability of IM and LVC using gadobutrol.

  6. Enhanced critical currents in (Gd,Y)Ba2Cu3Ox superconducting tapes with high levels of Zr addition

    Energy Technology Data Exchange (ETDEWEB)

    Selvamanickam, V; Chen, Y; Shi, T; Liu, Y; Khatri, ND; Liu, J; Yao, Y; Xiong, X; Lei, C; Soloveichik, S; Galstyan, E; Majkic, G

    2013-01-21

    The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba2Cu3Ox film. By a modified MOCVD process,enhanced critical current densities have been achieved with high levels of Zr addition,including 3.83 MA cm(-2) in 15 at.% Zr- added 1.1 mu m thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/ 12 mm have been reached in (Gd,Y) BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape,corresponding to a pinning force value of 268 GN m(-3). The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second- phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met.

  7. Enhanced critical currents in (Gd,Y)Ba2Cu3Ox superconducting tapes with high levels of Zr addition

    International Nuclear Information System (INIS)

    Selvamanickam, V; Shi, T; Liu, Y; Khatri, N D; Liu, J; Yao, Y; Galstyan, E; Majkic, G; Chen, Y; Xiong, X; Lei, C; Soloveichik, S

    2013-01-01

    The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba 2 Cu 3 O x film. By a modified MOCVD process, enhanced critical current densities have been achieved with high levels of Zr addition, including 3.83 MA cm −2 in 15 at.% Zr-added 1.1 μm thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/12 mm have been reached in (Gd,Y)BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape, corresponding to a pinning force value of 268 GN m −3 . The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second-phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met. (paper)

  8. Hepatoblastoma imaging with gadoxetate disodium-enhanced MRI - typical, atypical, pre- and post-treatment evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, Arthur B. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Medical College of Wisconsin, Department of Radiology, Milwaukee, WI (United States); Children' s Hospital of Wisconsin, Department of Pediatric Imaging, Milwaukee, WI (United States); Towbin, Alexander J.; Podberesky, Daniel J. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Geller, James I. [Cincinnati Children' s Hospital Medical Center, Department of Hematology/Oncology, Cincinnati, OH (United States)

    2012-07-15

    Gadoxetate disodium (Gd-EOB-DTPA) is a hepatobiliary MRI contrast agent widely used in adults for characterization of liver tumors and increasingly used in children. Hepatoblastoma is the most common primary hepatic malignancy of childhood. In this review, we describe our experience with this agent both before and after initiating therapy in children with hepatoblastoma. (orig.)

  9. Pressure-enhanced light emission and its structural origin in Er:GdVO 4

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Fang; Yue, Binbin; Cheng, Zhenxiang; Shen, Hui; Yang, Ke; Hong, Xinguo; Chen, Bin; Mao, Ho-Kwang

    2017-01-09

    Rare earth phosphors have been widely studied because of their sharp emission lines and excellent optical performance. However, photoluminescence (PL) tuning by crystal field in Er3+ embedded phosphors has always been a challenge. Here, we demonstrate that pressure can help to enhance the red and green light emission simultaneously in Er:GdVO4. Synchrotron X-ray diffraction investigations revealed that a structural phase transition was responsible for the enhancement. Our work brightens the future prospects for applications of Er3+-based PL materials in various fields, such as high power lasers and (bio) medical imaging.

  10. Magnetic nanoparticles induced dielectric enhancement in (La, Gd)2O3: SiO2 composite systems

    Science.gov (United States)

    Kao, T. H.; Mukherjee, S.; Yang, H. D.

    2013-11-01

    Magnetic Gd2O3 and non-magnetic La2O3 nanoparticles (NPs) have been synthesized together with different doping concentrations in SiO2 matrix via sol-gel route calcination at 700 °C and above. Properly annealed NP-glass composite systems show enhancement of dielectric constant and magnetodielectric effect (MDE) near room temperature, depending on superparamagnetic NPs concentrations. From application point of view, the enhancement of dielectric constant along with MDE can be achieved by tuning the NPs size through varying calcination temperature and/or increasing the doping concentration of magnetic rare earth oxide.

  11. Plain and Gd-DTPA-enhanced MR imaging in sjoegren syndrome of the parotid gland

    International Nuclear Information System (INIS)

    Vogl, T.J.; Dresel, S.; Spath, M.; Schedel, H.J.; Lissner, J.

    1990-01-01

    This paper reports that up to now in the diagnostic management of myoepithelial sialoadenitis (Sjogren syndrome), sialography was considered an essential imaging method. Now, results of MR imaging in this disease may offer new possibilities in diagnostic imaging. Twenty-eight patients with immunohistologically and serologically confirmed Sjogren syndrome were examined in transverse and coronal orientations. Images were obtained before and after Gd-DTPA administration with T1-weighted sequences (TR/TE = 500/25 msec) and before Gd-DTPA with T2-weighted sequences (TR/TE = 1600/90 msec)

  12. Influence of B{sub 1}-inhomogeneity on pharmacokinetic modeling of dynamic contrast-enhanced MRI: A simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Bun Woo [Dept. of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Byung Se [Dept. of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); and others

    2017-08-01

    To simulate the B1-inhomogeneity-induced variation of pharmacokinetic parameters on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). B1-inhomogeneity-induced flip angle (FA) variation was estimated in a phantom study. Monte Carlo simulation was performed to assess the FA-deviation-induced measurement error of the pre-contrast R1, contrast-enhancement ratio, Gd-concentration, and two-compartment pharmacokinetic parameters (Ktrans, ve, and vp). B1-inhomogeneity resulted in −23–5% fluctuations (95% confidence interval [CI] of % error) of FA. The 95% CIs of FA-dependent % errors in the gray matter and blood were as follows: −16.7–61.8% and −16.7–61.8% for the pre-contrast R1, −1.0–0.3% and −5.2–1.3% for the contrast-enhancement ratio, and −14.2–58.1% and −14.1–57.8% for the Gd-concentration, respectively. These resulted in −43.1–48.4% error for Ktrans, −32.3–48.6% error for the ve, and −43.2–48.6% error for vp. The pre-contrast R1 was more vulnerable to FA error than the contrast-enhancement ratio, and was therefore a significant cause of the Gd-concentration error. For example, a −10% FA error led to a 23.6% deviation in the pre-contrast R1, −0.4% in the contrast-enhancement ratio, and 23.6% in the Gd-concentration. In a simulated condition with a 3% FA error in a target lesion and a −10% FA error in a feeding vessel, the % errors of the pharmacokinetic parameters were −23.7% for Ktrans, −23.7% for ve, and −23.7% for vp. Even a small degree of B1-inhomogeneity can cause a significant error in the measurement of pharmacokinetic parameters on DCE-MRI, while the vulnerability of the pre-contrast R1 calculations to FA deviations is a significant cause of the miscalculation.

  13. Gd-DTPA T1 relaxivity in brain tissue obtained by convection-enhanced delivery, magnetic resonance imaging and emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Haar, Peter J [Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA (United States); Broaddus, William C; Chen Zhijian; Gillies, George T [Department of Neurosurgery, Virginia Commonwealth University, Richmond, VA (United States); Fatouros, Panos P; Corwin, Frank D, E-mail: wbroaddus@mcvh-vcu.ed [Department of Radiology, Virginia Commonwealth University, Richmond, VA (United States)

    2010-06-21

    A common approach to quantify gadolinium (Gd) contrast agents involves measuring the post-contrast change in T1 rate and then using the constant T1 relaxivity R to determine the contrast agent concentration. Because this method is fast and non-invasive, it could be potentially valuable in many areas of brain research. However, to accurately measure contrast agent concentrations in the brain, the T1 relaxivity R of the specific agent must be accurately known. Furthermore, the macromolecular content and compartmentalization of the brain extracellular space (ECS) are expected to significantly alter R from values measured in aqueous solutions. In this study, the T1 relaxivity R of gadolinium-diethylene-triamine penta-acetic acid (Gd-DTPA) was measured following direct interstitial infusions of three different contrast agent concentrations to the parenchyma of rat brains. Changes in magnetic resonance (MR) T1 values were compared to brain slice concentrations determined with inductively coupled plasma atomic emission spectroscopy (ICP-AES) to determine R in 15 rats. Additionally, samples of cerebrospinal fluid, blood and urine were analyzed to evaluate possible Gd-DTPA clearance from the brain. The T1 relaxivity R of Gd-DTPA in the brain ECS was measured to be 5.35 (mM s){sup -1} in a 2.4 T field. This value is considerably higher than estimations used in studies by other groups. Measurements of brain Gd-DTPA tissue concentrations using MRI and ICP-AES demonstrated a high degree of coincidence. Clearance of Gd-DTPA was minimal at the time point immediately after infusion. These results suggest that the environment of the brain does in fact significantly affect Gd T1 relaxivity, and that MRI can accurately measure contrast agent concentrations when this relaxivity is well characterized.

  14. Gd-DTPA T1 relaxivity in brain tissue obtained by convection-enhanced delivery, magnetic resonance imaging and emission spectroscopy

    Science.gov (United States)

    Haar, Peter J.; Broaddus, William C.; Chen, Zhi-jian; Fatouros, Panos P.; Gillies, George T.; Corwin, Frank D.

    2010-06-01

    A common approach to quantify gadolinium (Gd) contrast agents involves measuring the post-contrast change in T1 rate and then using the constant T1 relaxivity R to determine the contrast agent concentration. Because this method is fast and non-invasive, it could be potentially valuable in many areas of brain research. However, to accurately measure contrast agent concentrations in the brain, the T1 relaxivity R of the specific agent must be accurately known. Furthermore, the macromolecular content and compartmentalization of the brain extracellular space (ECS) are expected to significantly alter R from values measured in aqueous solutions. In this study, the T1 relaxivity R of gadolinium-diethylene-triamine penta-acetic acid (Gd-DTPA) was measured following direct interstitial infusions of three different contrast agent concentrations to the parenchyma of rat brains. Changes in magnetic resonance (MR) T1 values were compared to brain slice concentrations determined with inductively coupled plasma atomic emission spectroscopy (ICP-AES) to determine R in 15 rats. Additionally, samples of cerebrospinal fluid, blood and urine were analyzed to evaluate possible Gd-DTPA clearance from the brain. The T1 relaxivity R of Gd-DTPA in the brain ECS was measured to be 5.35 (mM s)-1 in a 2.4 T field. This value is considerably higher than estimations used in studies by other groups. Measurements of brain Gd-DTPA tissue concentrations using MRI and ICP-AES demonstrated a high degree of coincidence. Clearance of Gd-DTPA was minimal at the time point immediately after infusion. These results suggest that the environment of the brain does in fact significantly affect Gd T1 relaxivity, and that MRI can accurately measure contrast agent concentrations when this relaxivity is well characterized.

  15. Gd-DTPA T1 relaxivity in brain tissue obtained by convection-enhanced delivery, magnetic resonance imaging and emission spectroscopy

    International Nuclear Information System (INIS)

    Haar, Peter J; Broaddus, William C; Chen Zhijian; Gillies, George T; Fatouros, Panos P; Corwin, Frank D

    2010-01-01

    A common approach to quantify gadolinium (Gd) contrast agents involves measuring the post-contrast change in T1 rate and then using the constant T1 relaxivity R to determine the contrast agent concentration. Because this method is fast and non-invasive, it could be potentially valuable in many areas of brain research. However, to accurately measure contrast agent concentrations in the brain, the T1 relaxivity R of the specific agent must be accurately known. Furthermore, the macromolecular content and compartmentalization of the brain extracellular space (ECS) are expected to significantly alter R from values measured in aqueous solutions. In this study, the T1 relaxivity R of gadolinium-diethylene-triamine penta-acetic acid (Gd-DTPA) was measured following direct interstitial infusions of three different contrast agent concentrations to the parenchyma of rat brains. Changes in magnetic resonance (MR) T1 values were compared to brain slice concentrations determined with inductively coupled plasma atomic emission spectroscopy (ICP-AES) to determine R in 15 rats. Additionally, samples of cerebrospinal fluid, blood and urine were analyzed to evaluate possible Gd-DTPA clearance from the brain. The T1 relaxivity R of Gd-DTPA in the brain ECS was measured to be 5.35 (mM s) -1 in a 2.4 T field. This value is considerably higher than estimations used in studies by other groups. Measurements of brain Gd-DTPA tissue concentrations using MRI and ICP-AES demonstrated a high degree of coincidence. Clearance of Gd-DTPA was minimal at the time point immediately after infusion. These results suggest that the environment of the brain does in fact significantly affect Gd T1 relaxivity, and that MRI can accurately measure contrast agent concentrations when this relaxivity is well characterized.

  16. Sturge-Weber syndrome with no leptomeningeal enhancement on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Fischbein, N.J.; Barkovich, A.J. [Department of Radiology, San Francisco, CA (United States); Wu, Y.; Berg, B.O. [Department Pediatric Neurology, University of California, San Francisco, California (United States)

    1998-03-01

    Sturge-Weber syndrome (SWS) is a neurocutaneous syndrome characterized by a facial nevus flammeus associated with seizures, developmental delay, and, often, with hemiparesis and hemianopia. On MRI, the most characteristic finding has been reported to be leptomeningeal enhancement, believed to represent leakage of contrast medium through the anomalous pial vessels that characterize the disease. We present a case of SWS with no evidence of leptomeningeal enhancement. This case illustrates that leptomeningeal enhancement need not be present in SWS, and the absence of this characteristic finding does not preclude the diagnosis. (orig.) With 2 figs.

  17. Dynamic oxygen-enhanced MRI of cerebrospinal fluid.

    Directory of Open Access Journals (Sweden)

    Taha M Mehemed

    Full Text Available Oxygen causes an increase in the longitudinal relaxation rate of tissues through its T1-shortening effect owing to its paramagnetic properties. Due to such effects, MRI has been used to study oxygen-related signal intensity changes in various body parts including cerebrospinal fluid (CSF space. Oxygen enhancement of CSF has been mainly studied using MRI sequences with relatively longer time resolution such as FLAIR, and T1 value calculation. In this study, fifteen healthy volunteers were scanned using fast advanced spin echo MRI sequence with and without inversion recovery pulse in order to dynamically track oxygen enhancement of CSF. We also focused on the differences of oxygen enhancement at sulcal and ventricular CSF. Our results revealed that CSF signal after administration of oxygen shows rapid signal increase in both sulcal CSF and ventricular CSF on both sequences, with statistically significant predominant increase in sulcal CSF compared with ventricular CSF. CSF is traditionally thought to mainly form from the choroid plexus in the ventricles and is absorbed at the arachnoid villi, however, it is also believed that cerebral arterioles contribute to the production and absorption of CSF, and controversy remains in terms of the precise mechanism. Our results demonstrated rapid oxygen enhancement in sulcal CSF, which may suggest inhaled oxygen may diffuse into sulcal CSF space rapidly probably due to the abundance of pial arterioles on the brain sulci.

  18. Aiming for a shorter rheumatoid arthritis MRI protocol: can contrast-enhanced MRI replace T2 for the detection of bone marrow oedema?

    Energy Technology Data Exchange (ETDEWEB)

    Stomp, Wouter; Bloem, Johan L.; Reijnierse, Monique [Leiden University Medical Center, Department of Radiology, P.O. Box 9600, Leiden (Netherlands); Krabben, Annemarie; Heijde, Desiree van der; Huizinga, Tom W.J.; Helm-van Mil, Annette H.M. van der [Leiden University Medical Center, Department of Rheumatology, P.O. Box 9600, Leiden (Netherlands)

    2014-10-15

    To determine whether T1 post-gadolinium chelate images (T1Gd) can replace T2-weighted images (T2) for evaluating bone marrow oedema (BME), thereby allowing a shorter magnetic resonance imaging (MRI) protocol in rheumatoid arthritis (RA). In 179 early arthritis patients and 43 advanced RA patients, wrist and metacarpophalangeal joints were examined on a 1.5-T extremity MRI system with a standard protocol (coronal T1, T2 fat-saturated and coronal and axial T1 fat-saturated after Gd). BME was scored according to OMERACT RAMRIS by two observers with and without T2 images available. Agreement was assessed using intraclass correlation coefficients (ICCs) for semi-quantitative scores and test characteristics with T2 images as reference. Agreement between scores based on T2 and T1Gd images was excellent ICC (0.80-0.99). At bone level, sensitivity and specificity of BME on T1Gd compared to T2 were high for both patient groups and both readers (all ≥80 %). T1Gd and T2 images are equally suitable for evaluating BME. Because contrast is usually administered to assess (teno)synovitis, a short MRI protocol of T1 and T1Gd is sufficient in RA. (orig.)

  19. Aiming for a shorter rheumatoid arthritis MRI protocol: can contrast-enhanced MRI replace T2 for the detection of bone marrow oedema?

    International Nuclear Information System (INIS)

    Stomp, Wouter; Bloem, Johan L.; Reijnierse, Monique; Krabben, Annemarie; Heijde, Desiree van der; Huizinga, Tom W.J.; Helm-van Mil, Annette H.M. van der

    2014-01-01

    To determine whether T1 post-gadolinium chelate images (T1Gd) can replace T2-weighted images (T2) for evaluating bone marrow oedema (BME), thereby allowing a shorter magnetic resonance imaging (MRI) protocol in rheumatoid arthritis (RA). In 179 early arthritis patients and 43 advanced RA patients, wrist and metacarpophalangeal joints were examined on a 1.5-T extremity MRI system with a standard protocol (coronal T1, T2 fat-saturated and coronal and axial T1 fat-saturated after Gd). BME was scored according to OMERACT RAMRIS by two observers with and without T2 images available. Agreement was assessed using intraclass correlation coefficients (ICCs) for semi-quantitative scores and test characteristics with T2 images as reference. Agreement between scores based on T2 and T1Gd images was excellent ICC (0.80-0.99). At bone level, sensitivity and specificity of BME on T1Gd compared to T2 were high for both patient groups and both readers (all ≥80 %). T1Gd and T2 images are equally suitable for evaluating BME. Because contrast is usually administered to assess (teno)synovitis, a short MRI protocol of T1 and T1Gd is sufficient in RA. (orig.)

  20. Pr and Gd co-doped bismuth ferrite thin films with enhanced ...

    Indian Academy of Sciences (India)

    in Pr content, the crystal structures of BPGFO thin films retain rhombohedral (R3c) symmetry accompanied by structure distortion. ... Pr and Gd co-modified BiFeO3 thin film; ferroelectric properties; sol-gel. 1. Introduction. In recent years, great attention has been paid to single- phase BiFeO3 (BFO) multiferroic materials ...

  1. A feasibility study evaluating the relationship between dose and focal liver reaction in stereotactic ablative radiotherapy for liver cancer based on intensity change of Gd-EOB-DTPA-enhanced magnetic resonance images

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Sang Hoon; Yu, Jeong Il; Park, Hee Chul; Lim, Do Hoon; Han, Young Yih [Dept. of Radiation Oncology, amsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2016-03-15

    In order to evaluate the relationship between the dose to the liver parenchyma and focal liver reaction (FLR) after stereotactic ablative body radiotherapy (SABR), we suggest a novel method using a three-dimensional dose distribution and change in signal intensity of gadoxetate disodium-gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) hepatobiliary phase images. In our method, change of the signal intensity between the pretreatment and follow-up hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI was calculated and then threshold dose (TD) for developing FLR was obtained from correlation of dose with the change of the signal intensity. For validation of the method, TDs for six patients, who had been treated for liver cancer with SABR with 45-60 Gy in 3 fractions, were calculated using the method, and we evaluated concordance between volume enclosed by isodose of TD by the method and volume identified as FLR by a physician. The dose to normal liver was correlated with change in signal intensity between pretreatment and follow-up MRI with a median R{sup 2} of 0.935 (range, 0.748 to 0.985). The median TD by the method was 23.5 Gy (range, 18.3 to 39.4 Gy). The median value of concordance was 84.5% (range, 44.7% to 95.9%). Our method is capable of providing a quantitative evaluation of the relationship between dose and intensity changes on follow-up MRI, as well as determining individual TD for developing FLR. We expect our method to provide better information about the individual relationship between dose and FLR in radiotherapy for liver cancer.

  2. A feasibility study evaluating the relationship between dose and focal liver reaction in stereotactic ablative radiotherapy for liver cancer based on intensity change of Gd-EOB-DTPA-enhanced magnetic resonance images

    International Nuclear Information System (INIS)

    Jung, Sang Hoon; Yu, Jeong Il; Park, Hee Chul; Lim, Do Hoon; Han, Young Yih

    2016-01-01

    In order to evaluate the relationship between the dose to the liver parenchyma and focal liver reaction (FLR) after stereotactic ablative body radiotherapy (SABR), we suggest a novel method using a three-dimensional dose distribution and change in signal intensity of gadoxetate disodium-gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) hepatobiliary phase images. In our method, change of the signal intensity between the pretreatment and follow-up hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI was calculated and then threshold dose (TD) for developing FLR was obtained from correlation of dose with the change of the signal intensity. For validation of the method, TDs for six patients, who had been treated for liver cancer with SABR with 45-60 Gy in 3 fractions, were calculated using the method, and we evaluated concordance between volume enclosed by isodose of TD by the method and volume identified as FLR by a physician. The dose to normal liver was correlated with change in signal intensity between pretreatment and follow-up MRI with a median R 2 of 0.935 (range, 0.748 to 0.985). The median TD by the method was 23.5 Gy (range, 18.3 to 39.4 Gy). The median value of concordance was 84.5% (range, 44.7% to 95.9%). Our method is capable of providing a quantitative evaluation of the relationship between dose and intensity changes on follow-up MRI, as well as determining individual TD for developing FLR. We expect our method to provide better information about the individual relationship between dose and FLR in radiotherapy for liver cancer

  3. 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.

  4. A Microfluidic Platform to design crosslinked Hyaluronic Acid Nanoparticles (cHANPs) for enhanced MRI

    Science.gov (United States)

    Russo, Maria; Bevilacqua, Paolo; Netti, Paolo Antonio; Torino, Enza

    2016-11-01

    Recent advancements in imaging diagnostics have focused on the use of nanostructures that entrap Magnetic Resonance Imaging (MRI) Contrast Agents (CAs), without the need to chemically modify the clinically approved compounds. Nevertheless, the exploitation of microfluidic platforms for their controlled and continuous production is still missing. Here, a microfluidic platform is used to synthesize crosslinked Hyaluronic Acid NanoParticles (cHANPs) in which a clinically relevant MRI-CAs, gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA), is entrapped. This microfluidic process facilitates a high degree of control over particle synthesis, enabling the production of monodisperse particles as small as 35 nm. Furthermore, the interference of Gd-DTPA during polymer precipitation is overcome by finely tuning process parameters and leveraging the use of hydrophilic-lipophilic balance (HLB) of surfactants and pH conditions. For both production strategies proposed to design Gd-loaded cHANPs, a boosting of the relaxation rate T1 is observed since a T1 of 1562 is achieved with a 10 μM of Gd-loaded cHANPs while a similar value is reached with 100 μM of the relevant clinical Gd-DTPA in solution. The advanced microfluidic platform to synthesize intravascularly-injectable and completely biocompatible hydrogel nanoparticles entrapping clinically approved CAs enables the implementation of straightforward and scalable strategies in diagnostics and therapy applications.

  5. New hallmark of hepatocellular carcinoma, early hepatocellular carcinoma and high-grade dysplastic nodules on Gd-EOB-DTPA MRI in patients with cirrhosis: a new diagnostic algorithm.

    Science.gov (United States)

    Renzulli, Matteo; Biselli, Maurizio; Brocchi, Stefano; Granito, Alessandro; Vasuri, Francesco; Tovoli, Francesco; Sessagesimi, Elisa; Piscaglia, Fabio; D'Errico, Antonietta; Bolondi, Luigi; Golfieri, Rita

    2018-02-03

    Many improvements have been made in diagnosing hepatocellular carcinoma (HCC), but the radiological hallmarks of HCC have remained the same for many years. We prospectively evaluated the imaging criteria of HCC, early HCC and high-grade dysplastic nodules (HGDNs) in patients under surveillance for chronic liver disease, using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) MRI and diffusion-weighted imaging. Our study population included 420 nodules >1 cm in 228 patients. The MRI findings of each nodule were collected in all sequences/phases. The diagnosis of HCC was made according to the American Association for the Study of Liver Diseases (AASLD) criteria; all atypical nodules were diagnosed using histology. A classification and regression tree was developed using three MRI findings which were independently significant correlated variables for early HCC/HCC, and the best sequence of their application in a new diagnostic algorithm (hepatobiliary hypointensity, arterial hyperintensity and diffusion restriction) was suggested. This algorithm demonstrated, both in the entire study population and for nodules ≤2 cm, higher sensitivity (96% [95% CI 93.5% to 97.6%] and 96.6% [95% CI 93.9% to 98.5%], P<0.001, respectively) and slightly lower specificity (91.8% [95% CI 88.6% to 94.1%], P=0.063, and 92.7% [95% CI 88.9% to 95.4%], P=0.125, respectively) than those of the AASLD criteria. Our new diagnostic algorithm also showed a very high sensitivity (94.7%; 95% CI 92% to 96.6%) and specificity (99.3%; 95% CI 97.7% to 99.8%) in classifying HGDN. Our new diagnostic algorithm demonstrated significantly higher sensitivity and comparable specificity than those of the AASLD imaging criteria for HCC in patients with cirrhosis evaluated using Gd-EOB-DTPA MRI, even for lesions ≤2 cm. Moreover, this diagnostic algorithm allowed evaluating other lesions which could arise in a cirrhotic liver, such as early HCC and HGDN. © Article author

  6. Molecular MRI of Cardiomyocyte Apoptosis with Simultaneous Delayed Enhancement MRI Distinguishes Apoptotic and Necrotic Myocytes In Vivo: Potential for Midmyocardial Salvage in Acute Ischemia

    Science.gov (United States)

    Sosnovik, David E.; Garanger, Elisabeth; Aikawa, Elena; Nahrendorf, Matthias; Figuiredo, Jose-Luiz; Dai, Guangping; Reynolds, Fred; Rosenzweig, Anthony; Weissleder, Ralph; Josephson, Lee

    2009-01-01

    Background A novel dual contrast molecular MRI technique to image both cardiomyocyte (CM) apoptosis and necrosis in-vivo within 4-6 hours of ischemia is presented. The technique utilizes the annexin-based nanoparticle AnxCLIO-Cy5.5 (apoptosis) and simultaneous delayed enhancement (DE) imaging with a novel gadolinium chelate, Gd-DTPA-NBD (necrosis). Methods and Results Mice with transient coronary ligation were injected intravenously at the onset of reperfusion with AnxCLIO-Cy5.5 (n=7) or the control probe Inact_CLIO-Cy5.5 (n=6). T2* weighted MR images (9.4 Tesla) were acquired within 4-6 hours of reperfusion. The contrast-to-noise ratio (CNR) between injured and uninjured myocardium was measured. The mice were then injected with Gd-DTPA-NBD and DE imaging was performed within 10-30 minutes. Uptake of AnxCLIO-Cy5.5 was most prominent in the midmyocardium and was significantly greater than that of Inact_CLIO-Cy5.5 (CNR 8.82 +/− 1.5 versus 3.78 +/− 1.1, p DTPA-NBD. Wall thickening was significantly reduced in segments with DE and/or transmural accumulation of AnxCLIO-Cy5.5 (p DTPA-NBD confirmed the presence of large numbers of apoptotic but potentially viable CMs (AnxCLIO-Cy5.5 positive, Gd-DTPA-NBD negative) in the midmyocardium. Conclusions A novel technique to image CM apoptosis and necrosis in-vivo within 4-6 hours of injury is presented, and reveals large areas of apoptotic but viable myocardium in the midmyocardium. Strategies to salvage the numerous apoptotic but potentially viable CMs in the midmyocardium in acute ischemia should be investigated. PMID:19920044

  7. Gd-DTPA-enhanced T{sub 1}-weighted excretory MR urography after low-dose diuretic injection; T{sub 1}-gewichtete MR-Ausscheidungsurographie mittels Gd-DTPA und vorheriger niedrigdosierter Gabe eines Diuretikums

    Energy Technology Data Exchange (ETDEWEB)

    Nolte-Ernsting, C.; Buecker, A.; Adam, G.; Neuerburg, J.; Guenther, R.W. [Universitaetsklinikum der RWTH Aachen (Germany). Klinik fuer Radiologische Diagnostik

    1997-09-01

    Purpose: Assessment of the morphology of the urinary tract by gadolinium(Gd)-enhanced T{sub 1}-weighted MR-urography (MRU) and precontrast diuretic injection. Methods: MRU was performed in 5 patients using Gd-DTPA-enhanced coronal T{sub 1}-weighted 3D-gradient-echo sequences with different spatial resolution. Prior to contrast injection, 10 mg of furosemide were administered intravenously. Results: Secondary to the precontrast furosemide injection, the increase of the renal excretion rate allows complete visualisation of the entire collecting system within 10 minutes following Gd injection. Maximum intensity projections provide a three-dimensional overview of the ureters separate from the bladder. To achieve detailed anatomic imaging of the calices, both optimal distension and high resolution sequences are prerequisites which cannot be realized by means of survey urograms only. (orig./AJ) [Deutsch] Ziel: Darstellung der Morphologie der ableitenden Harnwege mittels T{sub 1}-gewichteter MR-Urographie (MRU) nach Gabe eines nierengaengigen Gadolinium(Gd)-Chelates und vorheriger Diuretikumapplikation. Methoden: Der Harntrakt von 5 Patienten wurde nach Injektion von Gd-DTPA mit koronaren T{sub 1}-gewichteten 3D-Gradienten-Echo-Sequenzen unterschiedlicher Ortsaufloesung untersucht. Vor der Kontrastmittelgabe wurden jeweils 10 mg Furosemid intravenoes verabreicht. Ergebnisse: Nach initialer Steigerung des Harnflusses durch Furosemidgabe wurden Uebersichtsurogramme mit vollstaendig durchzeichnenden Ureteren bereits 10 min nach Gd-Injektion erzielt. Maximumintensitaetsprojektionen ermoeglichten die Beurteilung des dreidimensionalen Verlaufes der Ureteren ohne Blasenueberlagerung. Eine genauere anatomische Darstellung der Nierenkelche erforderte neben einem guten Fuellungszustand eine moeglichst hohe Sequenzaufloesung, die mit Uebersichtsurogrammen allein nicht zu erreichen war. (orig./AJ)

  8. The cerebral intravascular enhancement sign is not specific: a contrast-enhanced MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Bakshi, R.; Kinkel, W.R.; Bates, V.E.; Mechtler, L.L.; Kinkel, P.R. [Lucy Dent Imaging Center, University at Buffalo, NY (United States)

    1999-02-01

    The intravascular enhancement (IVE) sign, also known as the ``arterial enhancement sign``, is an abnormal finding in the brain on contrast-enhanced MRI studies. IVE has been described in arterial cerebrovascular disorders, most commonly in acute or subacute arterial ischemic infarcts. However, the specificity of this sign has not been established. We describe four patients with disorders other than arterial strokes in whom gadolinium-enhanced high-field (1.5 T) MRI suggested IVE. The conditions were herpes simplex viral encephalitis, idiopathic cerebellitis, pneumococcal meningitis, and superior sagittal sinus thrombosis with venous infarction. IVE in these cases may be due to multiple factors, including arterial, venous, perivascular, and leptomeningeal or sulcal contrast medium accumulation. Our observations suggest that arterial ischemia, previously described as the cardinal cause of IVE, probably does not explain all instances, and urge caution in interpreting this sign as a specific MRI manifestation of acute arterial infarction or ischemia. (orig.) With 4 figs., 1 tab., 44 refs.

  9. 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.

  10. 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.

  11. Luminescent GdVO_4:Sm"3"+ quantum dots enhance power conversion efficiency of bulk heterojunction polymer solar cells by Förster resonance energy transfer

    International Nuclear Information System (INIS)

    Bishnoi, Swati; Gupta, Vinay; Sharma, Gauri D.; Chand, Suresh; Sharma, Chhavi; Kumar, Mahesh; Haranath, D.; Naqvi, Sheerin

    2016-01-01

    In this work, we report enhanced power conversion efficiency (PCE) of bulk heterojunction polymer solar cells by Förster resonance energy transfer (FRET) from samarium-doped luminescent gadolinium orthovanadate (GdVO_4:Sm"3"+) quantum dots (QDs) to polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) polymer. The photoluminescence emission spectrum of GdVO_4:Sm"3"+ QDs overlaps with the absorption spectrum of PTB7, leading to FRET from GdVO_4:Sm"3"+ to PTB7, and significant enhancements in the charge-carrier density of excited and polaronic states of PTB7 are observed. This was confirmed by means of femtosecond transient absorption spectroscopy. The FRET from GdVO_4:Sm"3"+ QDs to PTB7 led to a remarkable increase in the power conversion efficiency (PCE) of PTB7:GdVO_4:Sm"3"+:PC_7_1BM ([6,6]-phenyl-C_7_1-butyric acid methyl ester) polymer solar cells. The PCE in optimized ternary blend PTB7:GdVO_4:Sm"3"+:PC_7_1BM (1:0.1:1.5) is increased to 8.8% from 7.2% in PTB7:PC_7_1BM. This work demonstrates the potential of rare-earth based luminescent QDs in enhancing the PCE of polymer solar cells.

  12. Whole-body MRI, dynamic contrast-enhanced MRI, and diffusion-weighted imaging for the staging of multiple myeloma

    Energy Technology Data Exchange (ETDEWEB)

    Dutoit, Julie C.; Verstraete, Koenraad L. [Ghent University Hospital, Department of Radiology, Ghent (Belgium)

    2017-06-15

    Magnetic resonance imaging (MRI) is the most sensitive imaging technique for the detection of bone marrow infiltration, and has therefore recently been included in the new diagnostic myeloma criteria, as proposed by the International Myeloma Working Group. Nevertheless, conventional MRI only provides anatomical information and is therefore only of limited use in the response assessment of patients with multiple myeloma. The additional information from functional MRI techniques, such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, can improve the detection rate of bone marrow infiltration and the assessment of response. This can further enhance the sensitivity and specificity of MRI in the staging of multiple myeloma patients. This article provides an overview of the technical aspects of conventional and functional MRI techniques with practical recommendations. It reviews the diagnostic performance, prognostic value, and role in therapy assessment in multiple myeloma and its precursor stages. (orig.)

  13. 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.

  14. 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

  15. Clinicopathological findings in symptomatic Rathke's cleft cyst. Correlation between enhancement effects on MRI and histopathology of the cyst wall

    International Nuclear Information System (INIS)

    Niwa, Jun; Tanabe, Sumiyoshi; Ibayashi, Yukihiro; Hashi, Kazuo; Satoh, Masaaki

    1996-01-01

    We have studied MR images and the histopathology of eight patients with symptomatic Rathke's cleft cysts. Six cases showed visual disturbance and two showed galactorrhea. In five, the cyst fluid had low signal intensity on T1-weighted images and high intensity on T2-weighted images; in 2, the cyst fluid had high intensity on both T1- and T2-weighted images; in 1, the cyst fluid had high intensity on T1-weighted images and low intensity on T2-weighted images. Enhancement of the cyst wall by Gd-DTPA was able to be distinguished in 6 patients: 2 showed no enhancement, 2 showed thin enhancement and the remaining 2, thick enhancement. Fluid aspiration and total resection of the cyst wall was performed in all patients (3 by the transcranial approach and 5 by the transsphenoidal approach). Normal pituitary glands were found in all cases during the operations. Histopathologically, ciliated epithelium with goblet cells was recognized in 3. Non-ciliated epithelium was recognized in the other 5. Stratified squamous component was recognized in 1 and secondary inflammation, in another. Normal pituitary tissue was recognized in 5. Immunohistochemically, ciliated and non-ciliated epithelium was successfully stained for detecting antibody against epithelial membrane antigen and/or carcinoembryonic antigen. Two cases with no enhancement of the cyst wall by Gd-DTPA showed only ciliated epithelium. Two patients with thin enhancement of the cyst wall had single layer epithelium with normal pituitary tissue. Two patients with thick enhancement of the cyst wall showed single layer epithelium with its stratified squamous component or with secondary inflammation. A close relationship was suggested between the enhancement effect on MRI and histopathology of the cyst wall. (author)

  16. Nanodiamond-enhanced MRI via in situ hyperpolarization

    Science.gov (United States)

    Waddington, David E. J.; Sarracanie, Mathieu; Zhang, Huiliang; Salameh, Najat; Glenn, David R.; Rej, Ewa; Gaebel, Torsten; Boele, Thomas; Walsworth, Ronald L.; Reilly, David J.; Rosen, Matthew S.

    2017-04-01

    Nanodiamonds are of interest as nontoxic substrates for targeted drug delivery and as highly biostable fluorescent markers for cellular tracking. Beyond optical techniques, however, options for noninvasive imaging of nanodiamonds in vivo are severely limited. Here, we demonstrate that the Overhauser effect, a proton-electron polarization transfer technique, can enable high-contrast magnetic resonance imaging (MRI) of nanodiamonds in water at room temperature and ultra-low magnetic field. The technique transfers spin polarization from paramagnetic impurities at nanodiamond surfaces to 1H spins in the surrounding water solution, creating MRI contrast on-demand. We examine the conditions required for maximum enhancement as well as the ultimate sensitivity of the technique. The ability to perform continuous in situ hyperpolarization via the Overhauser mechanism, in combination with the excellent in vivo stability of nanodiamond, raises the possibility of performing noninvasive in vivo tracking of nanodiamond over indefinitely long periods of time.

  17. Mechanism of luminescent enhancement in Ba{sub 2}GdNbO{sub 6}:Eu{sup 3+} perovskite by Li{sup +} co-doping

    Energy Technology Data Exchange (ETDEWEB)

    Rezende, Marcos Vinicius dos Santos [Departamento de Física, Universidade Federal de Sergipe, 49500-000, Itabaiana, SE (Brazil); Valério, Mario Ernesto Giroldo [Departamento de Física, Universidade Federal de Sergipe, 49100-000 São Cristóvão, SE (Brazil); Mouta, Rodolpho; Diniz, Eduardo Moraes [Departamento de Física, CCET, Universidade Federal do Maranhão, 65085-580 São Luís, MA (Brazil); Paschoal, Carlos William de Araujo, E-mail: paschoal@ufma.br [Departamento de Física, CCET, Universidade Federal do Maranhão, 65085-580 São Luís, MA (Brazil); Department of Materials Science and Engineering, University of California Berkeley, 94720-1760 Berkeley, CA (United States); Department of Physics, University of California Berkeley, 94720-7300 Berkeley, CA (United States)

    2015-02-15

    We investigated the Li{sup +} ion incorporation in Ba{sub 2}GdNbO{sub 6}:Eu{sup 3+} perovskite by atomistic simulations based on energy minimization. We predicted the most probable sites occupied by Eu{sup 3+} and Li{sup +} ions and the related charge-compensation mechanisms involved into these substitutions. The results show that the Eu{sup 3+} and Li{sup +} ions are incorporated mainly at the Gd{sup 3+} site. In the Li{sup +} ion case, there is a charge compensation by Nb{sub Gd}{sup •} {sup •} antisite. The crystal field parameters and the transition levels for the Eu{sup 3+} ion in the BGN:Eu{sup 3+} were calculated with basis on the simulated local symmetry of the Eu{sup 3+} site. The results show that the mechanism of luminescent properties enhancement is the symmetry distortion induced by the Li{sup +} co-doping. - Highlights: • We performed a full defect calculations in Ba{sub 2}GdNbO{sub 6} double perovskite. • We modeled with excellent agreement the optical transition of Ba{sub 2}GdNbO{sub 6}:Eu{sup 3+} crystal. • We explained the mechanism of luminescent enhancement in Ba{sub 2}GdNbO{sub 6}:Eu{sup 3+} perovskite by Li{sup +} co-doping.

  18. Bile duct evaluation of potential living liver donors with Gd-EOB-DTPA enhanced MR cholangiography: Single-dose, double dose or half-dose contrast enhanced imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kinner, Sonja, E-mail: Sonja.Kinner@uni-due.de [Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen (Germany); Steinweg, Verena [Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen (Germany); Maderwald, Stefan [Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen (Germany); Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); Radtke, Arnold; Sotiropoulos, Georgios [Department of General Surgery, University Hospital Essen (Germany); Forsting, Michael; Schroeder, Tobias [Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen (Germany)

    2014-05-15

    Introduction: Detailed knowledge of the biliary anatomy is essential to avoid complications in living donor liver transplantation. The aim of this study was to determine the optimal dosage of Gd-EOB-DTPA for contrast-enhanced magnetic resonance cholangiography (ce-MRC) with reference to contrast-enhanced CT cholangiography (ce-CTC). Materials and methods: 30 potential living liver donors (PLLD) underwent both ce-CTC and ce-MRC. Ten candidates each received single, double or half-dose Gd-EOB-DTPA. Ce-MRC images with and without inversion recovery pulses (T1w ± IR) were acquired 20–30 min after intravenous contrast injection. Image data was quantitatively and qualitatively reviewed by two radiologists based on a on a 5-point scale. Data sets were compared using a Mann–Whitney-U-test or Wilcoxon-rank-sum-test. Kappa values were also calculated. Results: All image series provided sufficient diagnostic information both showing normal biliary anatomy and variant bile ducts. Ce-CTC showed statistically significant better results compared to all ce-MRC data sets. T1w MRC with single dose Gd-EOB-DTPA proved to be superior to half and double dose in subjective and objective evaluation without a statistically significant difference. Conclusions: Ce-MRC is at any dosage inferior to ce-CTC. As far as preoperative planning of bile duct surgery is focused on the central biliary anatomy, ce-MRC can replace harmful ce-CTC strategies, anyway. Best results were seen with single dose GD-EOB-DTPA on T1w MRC+IR.

  19. Enhancement patterns and pseudo-washout of hepatic haemangiomas on gadoxetate disodium-enhanced liver MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bohyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Byun, Jae Ho; Kim, Hyoung Jung; Won, Hyung Jin; Kim, So Yeon; Shin, Yong Moon; Kim, Pyo Nyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of)

    2016-01-15

    To compare the enhancement patterns and prevalence of pseudo-washout between rapidly and slowly enhancing hepatic haemangiomas on gadoxetate disodium-enhanced MRI in patients with chronic liver disease (CLD) and healthy liver (HL). On gadoxetate disodium-enhanced MRI, the extent of intralesional arterial enhancement >50 % and ≤50 % of lesions was defined as rapid and slow enhancement, respectively. The enhancement patterns and presence of pseudo-washout during the portal venous phase (PVP) and transitional phase (TP) of 74 hepatic haemangiomas were retrospectively evaluated in the CLD and HL groups. Sequential changes of signal-to-noise ratio (SNR) were measured in unenhanced phase, PVP and TP. Irrespective of hepatic health status, pseudo-washout in TP was significantly more common in the rapidly enhancing haemangiomas (p ≤ 0.026). In both groups, rapidly enhancing haemangiomas showed complete or progressive incomplete enhancement in PVP, which either lasted or transformed to pseudo-washout in TP, whereas slowly enhancing haemangiomas showed progressive incomplete enhancement in PVP and TP. SNR of hepatic parenchyma continued to rise until TP, whereas that of portal vein and haemangioma falls in TP. Regardless of CLD, pseudo-washout in TP was more common in rapidly than in slowly enhancing haemangiomas, with enhancement patterns differing in the two subgroups. (orig.)

  20. Enhancement patterns and pseudo-washout of hepatic haemangiomas on gadoxetate disodium-enhanced liver MRI

    International Nuclear Information System (INIS)

    Kim, Bohyun; Byun, Jae Ho; Kim, Hyoung Jung; Won, Hyung Jin; Kim, So Yeon; Shin, Yong Moon; Kim, Pyo Nyun

    2016-01-01

    To compare the enhancement patterns and prevalence of pseudo-washout between rapidly and slowly enhancing hepatic haemangiomas on gadoxetate disodium-enhanced MRI in patients with chronic liver disease (CLD) and healthy liver (HL). On gadoxetate disodium-enhanced MRI, the extent of intralesional arterial enhancement >50 % and ≤50 % of lesions was defined as rapid and slow enhancement, respectively. The enhancement patterns and presence of pseudo-washout during the portal venous phase (PVP) and transitional phase (TP) of 74 hepatic haemangiomas were retrospectively evaluated in the CLD and HL groups. Sequential changes of signal-to-noise ratio (SNR) were measured in unenhanced phase, PVP and TP. Irrespective of hepatic health status, pseudo-washout in TP was significantly more common in the rapidly enhancing haemangiomas (p ≤ 0.026). In both groups, rapidly enhancing haemangiomas showed complete or progressive incomplete enhancement in PVP, which either lasted or transformed to pseudo-washout in TP, whereas slowly enhancing haemangiomas showed progressive incomplete enhancement in PVP and TP. SNR of hepatic parenchyma continued to rise until TP, whereas that of portal vein and haemangioma falls in TP. Regardless of CLD, pseudo-washout in TP was more common in rapidly than in slowly enhancing haemangiomas, with enhancement patterns differing in the two subgroups. (orig.)

  1. The effect of FR enhancement in reactive ion beam sputtered Bi, Gd, Al-substituted iron- garnets: Bi2O3 nanocomposite films

    OpenAIRE

    Berzhansky, V.; Shaposhnikov, A.; Karavainikov, A.; Prokopov, A.; Mikhailova, T.; Lukienko, I.; Kharchenko, Yu.; Miloslavskaya, O.; Kharchenko, N.

    2012-01-01

    The effect of considerable Faraday rotation (FR) and figure of merit (Q) enhancement in Bi, Gd, Al-substituted iron garnets: Bi2O3 nano-composite films produced by separate reactive ion beam sputtered Bi:YIG and Bi2O3 films was found. It reached threefold enhancement of the FR and twofold of the Q one on GGG substrates.

  2. Detection of active bile leak with Gd-EOB-DTPA enhanced MR cholangiography: Comparison of 20–25 min delayed and 60–180 min delayed images

    International Nuclear Information System (INIS)

    Cieszanowski, Andrzej; Stadnik, Anna; Lezak, Aleksandra; Maj, Edyta; Zieniewicz, Krzysztof; Rowinska-Berman, Katarzyna; Grudzinski, Ireneusz P.; Krawczyk, Marek; Rowiński, Olgierd

    2013-01-01

    Objectives: The purpose of this study was to assess the value of contrast-enhanced magnetic resonance cholangiography (MRC) performed in different time delays after injection of gadoxetic acid disodium (Gd-EOB-DTPA) for the diagnosis of active bile leak. Methods: This retrospective analysis included Gd-EOB-DTPA enhanced MR images of 34 patients suspected of bile leak. Images were acquired 20–25 min after Gd-EOB-DTPA injection. If there was inadequate contrast in the bile ducts then delayed images after 60–90 min and 150–180 min were obtained. Results were correlated with intraoperative findings, ERCP results, clinical data, laboratory tests, and follow-up examinations. Results: Gd-EOB-DTPA enhanced MRC yielded an overall sensitivity of 96.4%, specificity of 100% and accuracy of 97.1% for the diagnosis of an active bile leak. The sensitivity of 20–25 min delayed MR images was 42.9%, of combined 20–25 min and 60–90 min delayed images was 92.9% and of combined 20–25 min, 60–90 min and 150–180 min delayed images was 96.4%. Conclusions: Gd-EOB-DTPA enhanced MRC utilizing delayed phase images was effective for detecting the presence and location of active bile leaks. The images acquired 60–180 min post-injection enabled identification of bile leaks even in patients with a dilated biliary system or moderate liver dysfunction

  3. Breast Dynamic Contrast Enhanced MRI: Fibrocystic Changes Presenting as a Non-mass Enhancement Mimicking Malignancy.

    Science.gov (United States)

    Milosevic, Zorica C; Nadrljanski, Mirjan M; Milovanovic, Zorka M; Gusic, Nina Z; Vucicevic, Slavko S; Radulovic, Olga S

    2017-06-01

    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 (NME)in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) examination. Forty-six patients with histologically proven fibrocystic changes (FCCs) were retrospectively reviewed, according to Breast Imaging Reporting and Data System (BI-RADS) lexicon. Prior to DCE-MRI examination, a unilateral breast lesion suspicious of malignancy was detected clinically, on mammography or breast ultrasonography. The predominant features of FCCs presenting as NME in DCE-MRI examination were: unilateral regional or diffuse distribution (in 35 patients or 76.1%), heterogeneous or clumped internal pattern of enhancement (in 36 patients or 78.3%), plateau time-intensity curve (in 25 patients or 54.3%), moderate or fast wash-in (in 31 patients or 67.4%).Nonproliferative lesions were found in 11 patients (24%), proliferative lesions without atypia in 29 patients (63%) and lesions with atypia in six patients (13%), without statistically significant difference of morphokinetic features, except of the association of clustered microcysts with proliferative dysplasia without atypia. FCCs presenting as NME in DCE-MRI examination have several morphokinetic features suspicious of malignancy, therefore requiring biopsy (BI-RADS 4). Nonproliferative lesions, proliferative lesions without atypia and proliferative lesions with atypia predominantly share the same predefined DCE-MRI morphokinetic features.

  4. Unexpected Coexisting Myocardial Infarction Detected by Delayed Enhancement MRI

    Directory of Open Access Journals (Sweden)

    Edouard Gerbaud

    2009-01-01

    Full Text Available We report a case of an unexpected coexisting anterior myocardial infarction detected by delayed enhancement MRI in a 41-year-old man following a presentation with a first episode of chest pain during inferior acute myocardial infarction. This second necrotic area was not initially suspected because there were no ECG changes in the anterior leads and the left descending coronary artery did not present any significant stenoses on emergency coronary angiography. Unrecognised myocardial infarction may carry important prognostic implications. CMR is currently the best imaging technique to detect unexpected infarcts.

  5. 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.

  6. The thoracic aortography by Gd-DTPA enhanced ultrafast cine MR imaging. Assessment of thoracic aortic dilatation in aging and in patients with hypertension and aortic valve disease

    International Nuclear Information System (INIS)

    Matsumura, Kentaro; Nakase, Emiko; Kawai, Ichiyoshi; Saito, Takayuki; Kikkawa, Nobutada; Haiyama, Toru

    1995-01-01

    To assess the morphology of thoracic aorta, we had a trial of Gd-DTPA enhanced ultrafast cine MR imaging on the thoracic aorta. This method was provided with high quality thoracic aortogram during 15-20 seconds. In patients without hypertension and aortic valve disease, dimensions of ascending aorta and aortic arch were significantly correlated with aging. In patients with hypertension, dimensions of ascending aorta and aortic arch were significantly dilated. In patients with aortic valve disease, thoracic aorta was diffusely enlarged, especially in ascending aorta. Gd-DTPA enhanced ultrafact cine MR imaging was useful to assess the thoracic aortic anatomy and diseases. (author)

  7. Quantification of synovistis by MRI: correlation between dynamic and static gadolinium-enhanced magnetic resonance imaging and microscopic and macroscopic signs of synovial inflammation

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Stoltenberg, M; Løvgreen-Nielsen, P

    1998-01-01

    injection, as the highest correlation coefficients to histologic inflammation were observed in this interval. Dynamic MRI can be used to determine synovial inflammation. Evaluation of large synovial areas one-half to one minute after Gd injection best reflects joint inflammation....... as at the four biopsy sites, and compared to synovial pathology. The rate of early enhancement of the total synovial membrane of the preselected slice, determined by dynamic MRI, was highly correlated with microscopic evidence of active inflammation (Spearman p = 0.73; p ... knees with and without synovial inflammation with a high predictive value (0.81-0.90). Moderate and severe inflammation could not be differentiated. The early enhancement rate was correlated with histologic features of active inflammation, particularly vessel proliferation and mononuclear leucocyte...

  8. 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

  9. Optimising the design of paramagnetic MRI contrast agents: influence of backbone substitution on the water exchange rate of Gd-DTPA derivatives.

    Science.gov (United States)

    Laurent, S; Botteman, F; Vander Elst, L; Muller, R N

    2004-04-01

    Among other factors influencing the residence time of the coordinated water (tauM) of paramagnetic contrast agents, the steric hindrance around the gadolinium ion seems to play a beneficial role. Such a crowding can be achieved by substituting the Gd-DTPA backbone on the C4 position. Several Gd-DTPA complexes carrying diverse groups at this position have thus been synthesised and characterised: GdS-C4-Me-DTPA, GdS-C4-n-Bu-DTPA, GdS-C4-iBu-DTPA, GdS-C4-iPr-DTPA, and Gd-C4-diMe-DTPA. TauM has been measured through the evolution of the water oxygen-17 transverse relaxation rate as a function of the temperature. The data show a reduction of tauM of GdS-C4-Me-DTPA, GdS-C4-n-Bu-DTPA, GdS-C4-iBu-DTPA, GdS-C4-iPr-DTPA, and Gd-C4-diMe-DTPA (tauM310 = 91,82, 108,98, and 57 ns respectively, as compared to Gd-DTPA (tauM310 = 143 ns)). At 310 K, the nuclear magnetic dispersion relaxation profiles of water protons are very similar for the five complexes which present longitudinal relaxivities slightly higher than those of Gd-DTPA. Regarding zinc transmetallation, C4-monosubstituted derivatives are more stable than Gd-DTPA. These results confirm that a judicious substitution of the DTPA skeleton allows for an acceleration of the coordinated water exchange rate. This observation can be useful for the design of vectorised contrast agents for molecular imaging. Copyright 2004 ESMRMB

  10. Gd-DTPA: a bowel contrast agent for magnetic resonance imaging of the abdomen

    International Nuclear Information System (INIS)

    Vlahos, L.; Gouliamos, A.; Clauss, W.; Kalovidouris, A.; Hadjiioannou, A.; Athanasopoulou, A.; Trakadas, S.; Papavasiliou, C.

    1992-01-01

    Forty patients with suspected pathology in the abdomen and pelvis have been investigated with MRI before and after administration of Gd-DTPA as an oral or rectal solution. The findings are analysed with respect to: (a) filling of the GI tract; (b) contrast in the region of interest, surrounding fat and vessels; (c) diagnostic yield in comparison to non-enhanced MRI and contrast CT. At a concentration of 1 mmol/l Gd-DTPA provided consistent positive contrast in the stomach and bowel in all cases. In 57.5% of cases we achieved complete filling of the GI tract. The opacification in the region of interest was good or satisfactory in 90% of cases. The diagnostic value of contrast MRI was better in 93% of cases than the non-enhanced MRI of the abdomen. In comparison with contrast CT, the contrast MRI was better or of the same value in 92% of cases. Despite the disadvantage of poor fat-to-bowel contrast (35% of cases were classified as poor), it is concluded that Gd-DTPA-enhanced MRI provides good delineation of organs adjacent to the bowel so this contrast agent has potential for a future role in abdominal MRI. (orig.)

  11. Gd-DTPA: a bowel contrast agent for magnetic resonance imaging of the abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Vlahos, L. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece); Gouliamos, A. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece); Clauss, W. [Schering A. G., Berlin (Germany); Kalovidouris, A. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece); Hadjiioannou, A. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece); Athanasopoulou, A. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece); Trakadas, S. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece); Papavasiliou, C. [Dept. of Radiology, Univ. of Athens, Areteion Hospital (Greece)

    1992-08-01

    Forty patients with suspected pathology in the abdomen and pelvis have been investigated with MRI before and after administration of Gd-DTPA as an oral or rectal solution. The findings are analysed with respect to: (a) filling of the GI tract; (b) contrast in the region of interest, surrounding fat and vessels; (c) diagnostic yield in comparison to non-enhanced MRI and contrast CT. At a concentration of 1 mmol/l Gd-DTPA provided consistent positive contrast in the stomach and bowel in all cases. In 57.5% of cases we achieved complete filling of the GI tract. The opacification in the region of interest was good or satisfactory in 90% of cases. The diagnostic value of contrast MRI was better in 93% of cases than the non-enhanced MRI of the abdomen. In comparison with contrast CT, the contrast MRI was better or of the same value in 92% of cases. Despite the disadvantage of poor fat-to-bowel contrast (35% of cases were classified as poor), it is concluded that Gd-DTPA-enhanced MRI provides good delineation of organs adjacent to the bowel so this contrast agent has potential for a future role in abdominal MRI. (orig.)

  12. Serial gadolinium-enhanced magnetic resonance imaging in patients with multiple sclerosis treated with mitoxantrone

    International Nuclear Information System (INIS)

    Krapf, H.; Mauch, E.; Fetzer, U.; Laufen, H.; Kornhuber, H.H.

    1995-01-01

    Serial gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) was used to monitor the effect of mitoxantrone in ten patients with rapidly deteriorating multiple sclerosis (MS). MRI was performed as a baseline and thereafter at 1, 3, 6, 9, 12 and 24 months. The total number of Gd-enhancing lesions diminished from 169 at baseline to 10 after 1 year and to 5 after 2 years. This reduction and the percentage of follow-up MRI studies showing no Gd enhancement were more pronounced than in other MRI studies of the natural course of MS. Measured with quantitative neurological scales, only one patient showed deterioration after 2 years; nevertheless, the changes in MRI were much more marked than those observed clinically. Serial Gd-MRI therefore, seems necessary for documenting efficacy in future therapeutic trails. (orig.)

  13. Delayed gadolinium-enhanced MRI of the fibrocartilage disc of the temporomandibular joint--a feasibility study.

    Science.gov (United States)

    Pittschieler, Elisabeth; Szomolanyi, Pavol; Schmid-Schwap, Martina; Weber, Michael; Egerbacher, Monika; Traxler, Hannes; Trattnig, Siegfried

    2014-12-01

    To 1) test the feasibility of delayed Gadolinium-Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC) at 3 T in the temporomandibular joint (TMJ) and 2) to determine the optimal delay for measurements of the TMJ disc after i.v. contrast agent (CA) administration. MRI of the right and left TMJ of six asymptomatic volunteers was performed at 3 T using a dedicated coil. 2D inversion recovery (2D-IR) sequences were performed at 4 time points covering 120 minutes and 3D gradient-echo (3D GRE) dual flip-angle sequences were performed at 14 time points covering 130 minutes after the administration of 0.2 mmol/kg of Gd-diethylenetriamine pentaacetic acid ion (Gd-DTPA)(2-), i.e., 0.4 mL of Magnevist™ per kg body weight. Pair-wise tests were used to assess differences between pre-and post-contrast T1 values. 2D-IR sequences showed a statistically significant drop (pfibrocartilage disc of the TMJ. The recommended measurement time for dGEMRIC in the TMJ after i.v. CA administration is from 60 to 120 minutes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Delayed gadolinium-enhanced MRI of the fibrocartilage disc of the temporomandibular joint – a feasibility study

    Science.gov (United States)

    Pittschieler, Elisabeth; Szomolanyi, Pavol; Schmid-Schwap, Martina; Weber, Michael; Egerbacher, Monika; Traxler, Hannes; Trattnig, Siegfried

    2014-01-01

    Objective To 1) test the feasibility of delayed Gadolinium-Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC) at 3 T in the temporomandibular joint (TMJ) and 2) to determine the optimal delay for measurements of the TMJ disc after i.v. contrast agent (CA) administration. Design MRI of the right and left TMJ of six asymptomatic volunteers was performed at 3 T using a dedicated coil. 2D inversion recovery (2D-IR) sequences were performed at 4 time points covering 120 minutes and 3D gradient-echo (3D GRE) dual flip-angle sequences were performed at 14 time points covering 130 minutes after the administration of 0.2 mmol/kg of Gd-diethylenetriamine pentaacetic acid ion (Gd-DTPA)2-, i.e., 0.4 mL of Magnevist™ per kg body weight. Pair-wise tests were used to assess differences between pre-and post-contrast T1 values. Results 2D-IR sequences showed a statistically significant drop (p fibrocartilage disc of the TMJ. The recommended measurement time for dGEMRIC in the TMJ after i.v. CA administration is from 60 to 120 minutes. PMID:25131629

  15. EPR spectroscopy of MRI-related Gd(III) complexes: simultaneous analysis of multiple frequency and temperature spectra, including static and transient crystal field effects.

    Science.gov (United States)

    Rast, S; Borel, A; Helm, L; Belorizky, E; Fries, P H; Merbach, A E

    2001-03-21

    For the first time, a very general theoretical method is proposed to interpret the full electron paramagnetic resonance (EPR) spectra at multiple temperatures and frequencies in the important case of S-state metal ions complexed in liquid solution. This method is illustrated by a careful analysis of the measured spectra of two Gd3+ (S = 7/2) complexes. It is shown that the electronic relaxation mechanisms at the origin of the EPR line shape arise from the combined effects of the modulation of the static crystal field by the random Brownian rotation of the complex and of the transient zero-field splitting. A detailed study of the static crystal field mechanism shows that, contrarily to the usual global models involving only second-order terms, the fourth and sixth order terms can play a non-negligible role. The obtained parameters are well interpreted in the framework of the physics of the various underlying relaxation processes. A better understanding of these mechanisms is highly valuable since they partly control the efficiency of paramagnetic metal ions in contrast agents for medical magnetic resonance imaging (MRI).

  16. 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.

  17. Temperature effects on separation of Gd3+ from Gd-DTPA-folate using nanofiltration method

    Science.gov (United States)

    Rahayu, I.; Indraneli, R. P.; Yuliyati, Y. B.; Anggraeni, A.; Soedjanaatmadja, U. M. S.; Bahti, H. H.

    2018-05-01

    MRI is one of the best techniques in medical diagnostics. Contrast agents are used to improve the visual of organs that are difficult to distinguish through MRI. Gd-DTPA-folate is one of the specific contrast agents against cancer diagnosis, because it has a high affinity to folate receptors. In the complexing Gd-DTPA-folate, does not rule out the complexity step runs imperfectly, so there is still Gd3+ in the Gd-DTPA-folate complex. The separation of Gd3+ from the Gd-DTPA-folate complex is important to eliminate toxic effects on the contrast agent. This study aims to determine the effect of temperature on the separation of Gd-DTPA-folate from Gd3+ with nanofiltration. The method are preparation Gd-DTPA-folate from GdCl3.6H2O and DTPA-folate by reflux method, then separated Gd-DTPA-folate complex from Gd3+ with nanofiltration at variation temperature (40, 41, 42, 43, 44oC ). Then, the values of flux and rejection coefficients were analyzed. The results showed that the optimum temperature for the separation of Gd3+ from Gd-DTPA-folate was achieved at 42.6°C with the rejection coefficient of 24% and the permeate flux of 403 L.m-2.h-1.

  18. MRI evaluation and treatment of osteoporotic vertebral compression fracture

    International Nuclear Information System (INIS)

    Yamaguchi, Ken; Otani, Koji

    2003-01-01

    The purpose of this study was to investigate the relation between Gd-DTPA enhanced MRI findings and the prognosis of the fractured vertebral body in the patients with fresh osteoporotic compression vertebral fractures. Subjects were 8 cases, 11 vertebrae. All of the cases were treated with no bed rest and no corset. MRI and radiographs were taken within 1 week after injury. MRI signal intensity of the fractured vertebral body altered low on T1WI at acute phase. When the fractured vertebrae were enhanced at whole area with Gd-DTPA at acute phase, the vertebrae showed no progression of wedge deformity by follow up radiographs. On the other hand, when the fractured vertebrae were not enhanced at whole area, the vertebrae showed progression of wedge deformity. These findings suggests that vertebral fractures in osteoporosis should be taken MRI including GD-DTPA in acute phase after injury. When the fractured vertebrae are enhanced with Gd-DTPA in whole body at acute phase, the fracture may need no special treatment. In conclusion, Gd-DTPA enhanced MRI may be useful to determine the prognosis of the osteoporotic compression fracture. (author)

  19. MRI Background Parenchymal Enhancement Is Not Associated with Breast Cancer.

    Directory of Open Access Journals (Sweden)

    Barbara Bennani-Baiti

    Full Text Available Previously, a strong positive association between background parenchymal enhancement (BPE at magnetic resonance imaging (MRI and breast cancer was reported in high-risk populations. We sought to determine, whether this was also true for non-high-risk patients.540 consecutive patients underwent breast MRI for assessment of breast findings (BI-RADS 0-5, non-high-risk screening (no familial history of breast cancer, no known genetic mutation, no prior chest irradiation, or previous breast cancer diagnosis and subsequent histological work-up. For this IRB-approved study, BPE and fibroglandular tissue FGT were retrospectively assessed by two experienced radiologists according to the BI-RADS lexicon. Pearson correlation coefficients were calculated to explore associations between BPE, FGT, age and final diagnosis of breast cancer. Subsequently, multivariate logistic regression analysis, considering covariate colinearities, was performed, using final diagnosis as the target variable and BPE, FGT and age as covariates.Age showed a moderate negative correlation with FGT (r = -0.43, p<0.001 and a weak negative correlation with BPE (r = -0.28, p<0.001. FGT and BPE correlated moderately (r = 0.35, p<0.001. Final diagnosis of breast cancer displayed very weak negative correlations with FGT (r = -0.09, p = 0.046 and BPE (r = -0.156, p<0.001 and weak positive correlation with age (r = 0.353, p<0.001. On multivariate logistic regression analysis, the only independent covariate for prediction of breast cancer was age (OR 1.032, p<0.001.Based on our data, neither BPE nor FGT independently correlate with breast cancer risk in non-high-risk patients at MRI. Our model retained only age as an independent risk factor for breast cancer in this setting.

  20. MRI of the fingers in patients with systemic scleroderma. Early results of contrast-enhanced examinations on a dedicated MRI system

    International Nuclear Information System (INIS)

    Bonel, H.; Seemann, M.; Reiser, M.; Messer, G.; Walchner, M.; Roecken, M.

    1997-01-01

    Purpose. To estimate disease activity in patients with systemic sclerosis using contrast-enhanced MRI of the skin. Material and Methods. In a pre-study, sequences of a low-field (0.2 T) scanner (Artoscan, Esaote, Genova, Italy) were optimized for detection of intravenous contrast (0.1 mmol/l Gd-DTPA) in six patients with the autoimmune disease systemic scleroderma. Based on the results of the pre-study, 17 patients with scleroderma (7 sclerotic/10 active inflammatory disease) were scanned using gradient-spoiled 3D GRE sequences (FA 90 , TR 100 ms, TE 18 ms), which had been established as most sensitive for intravenous contrast. Contrast enhancement of the skin was determined quantitatively by contrast-to-noise ratios (CNR), comparing post- to pre-contrast and dynamic scans (for 6 min, 1 acquisition/min). Patients in the chronic state with sclerodactylia and active inflammation of the hands were considered separately and compared to a control group (n=10) matched according to age. Results. CNR increase after intravenous contrast was significantly higher in patients with active disease (86±16% increase) than sclerosing disease (29±3%, p [de

  1. 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.)

  2. MRI in predication of early hemorrhagic transformation after acute stroke

    International Nuclear Information System (INIS)

    Guo Gang; Wu Renhua; Mikulis, D.J.

    2007-01-01

    Objective: To investigate the relationship among early parenchymal enhancement, post- gadolinium (Gd) hyperintense middle cerebral artery (HMCA), and subsequent hemorrhagic transformation (HT) in patients with hyperacute ischemic stroke. Methods: Twenty-four consecutive patients with ischemic stroke who underwent MRI within 6 h [(4.3±1.4) h] of symptom onset were retrospectively reviewed. All of these patients underwent at least one follow-up MRI or non-enhanced CT study at 2 to 7 days. Post-Gd T 1 WI were analyzed for parenchymal enhancement and hyperintense MCA. Gradient echo MRI and CT were used for assessment of HT. Results: Ten patients developed HT on follow-up imaging (hemorrhagic group). Early parenchymal enhancement was found in 6 patients with HT (P 1 WI after Gd-DTPA administration are independent predictors of subsequent HT. (authors)

  3. Highly biocompatible TiO2:Gd3+ nano-contrast agent with enhanced longitudinal relaxivity for targeted cancer imaging

    Science.gov (United States)

    Chandran, Parwathy; Sasidharan, Abhilash; Ashokan, Anusha; Menon, Deepthy; Nair, Shantikumar; Koyakutty, Manzoor

    2011-10-01

    We report the development of a novel magnetic nano-contrast agent (nano-CA) based on Gd3+ doped amorphous TiO2 of size ~25 nm, exhibiting enhanced longitudinal relaxivity (r1) and magnetic resonance (MR) contrasting together with excellent biocompatibility. Quantitative T1 mapping of phantom samples using a 1.5 T clinical MR imaging system revealed that the amorphous phase of doped titania has the highest r1 relaxivity which is ~2.5 fold higher than the commercially used CA Magnevist™. The crystalline (anatase) samples formed by air annealing at 250 °C and 500 °C showed significant reduction in r1 values and MR contrast, which is attributed to the loss of proton-exchange contribution from the adsorbed water and atomic re-arrangement of Gd3+ ions in the crystalline host lattice. Nanotoxicity studies including cell viability, plasma membrane integrity, reactive oxygen stress and expression of pro-inflammatory cytokines, performed on human primary endothelial cells (HUVEC), human blood derived peripheral blood mononuclear cells (PBMC) and nasopharyngeal epidermoid carcinoma (KB) cell line showed excellent biocompatibility up to relatively higher doses of 200 μg ml-1. The potential of this nano-CA to cause hemolysis, platelet aggregation and plasma coagulation were studied using human peripheral blood samples and found no adverse effects, illustrating the possibility of the safe intravenous administration of these agents for human applications. Furthermore, the ability of these agents to specifically detect cancer cells by targeting molecular receptors on the cell membrane was demonstrated on folate receptor (FR) positive oral carcinoma (KB) cells, where the folic acid conjugated nano-CA showed receptor specific accumulation on cell membrane while leaving the normal fibroblast cells (L929) unstained. This study reveals that the Gd3+ doped amorphous TiO2 nanoparticles having enhanced magnetic resonance contrast and high biocompatibility is a promising candidate for

  4. Contrast enhanced liver MRI in patients with primary sclerosing cholangitis: inverse appearance of focal confluent fibrosis on delayed phase MR images with hepatocyte specific versus extracellular gadolinium based contrast agents.

    Science.gov (United States)

    Husarik, Daniela B; Gupta, Rajan T; Ringe, Kristina I; Boll, Daniel T; Merkle, Elmar M

    2011-12-01

    To assess the enhancement pattern of focal confluent fibrosis (FCF) on contrast-enhanced hepatic magnetic resonance imaging (MRI) using hepatocyte-specific (Gd-EOB-DTPA) and extracellular (ECA) gadolinium-based contrast agents in patients with primary sclerosing cholangitis (PSC). After institutional review board approval, 10 patients with PSC (6 male, 4 female; 33-61 years) with 13 FCF were included in this retrospective study. All patients had a Gd-EOB-DTPA-enhanced liver MRI exam, and a comparison ECA-enhanced MRI. On each T1-weighted dynamic dataset, the signal intensity (SI) of FCF and the surrounding liver as well as the paraspinal muscle (M) were measured. In the Gd-EOB-DTPA group, hepatocyte phase images were also included. SI FCF/SI M, SI liver/SI M, and [(SI liver - SI FCF)/SI liver] were compared between the different contrast agents for each dynamic phase using the paired Student's t-test. There was no significant difference in SI FCF/SI M in all imaging phases. SI liver/SI M was significantly higher for the Gd-EOB-DTPA group in the delayed phase (P DTPA group, mean [(SI liver - SI FCF)/SI liver] were as follows (values for ECA group in parentheses): unenhanced phase: 0.26 (0.26); arterial phase: 0.01 (-0.31); portal venous phase (PVP): -0.05 (-0.26); delayed phase (DP): 0.14 (-0.54); and hepatocyte phase: 0.26. Differences were significant for the DP (P DTPA-enhanced images. Copyright © 2011 AUR. Published by Elsevier Inc. All rights reserved.

  5. Construction of 0.15 Tesla Overhauser Enhanced MRI.

    Science.gov (United States)

    Tokunaga, Yuumi; Nakao, Motonao; Naganuma, Tatsuya; Ichikawa, Kazuhiro

    2017-01-01

    Overhauser enhanced MRI (OMRI) is one of the free radical imaging technologies and has been used in biomedical research such as for partial oxygen measurements in tumor, and redox status in acute oxidative diseases. The external magnetic field of OMRI is frequently in the range of 5-10 mTesla to ensure microwave penetration into small animals, and the S/N ratio is limited. In this study, a 0.15 Tesla OMRI was constructed and tested to improve the S/N ratio for a small sample, or skin measurement. Specification of the main magnet was as follows: 0.15 Tesla permanent magnet; gap size 160 mm; homogenous spherical volume of 80 mm in diameter. The OMRI resonator was designed based on TE 101 cavity mode and machined from a phosphorus deoxidized copper block for electron spin resonance (ESR) excitation and a solenoid transmission/receive resonator for NMR detection. The resonant frequencies and Q values were 6.38 MHz/150 and 4.31-4.41 GHz/120 for NMR and ESR, respectively. The Q values were comparable to those of conventional low field OMRI resonators at 15 mTesla. As expected, the MRI S/N ratio was improved by a factor of 30. Triplet dynamic nuclear polarization spectra were observed for 14 N carboxy-PROXYL, along the excitation microwave sweep. In the current setup, the enhancement factor was ca. 0.5. In conclusion, the results of this preliminary evaluation indicate that the 0.15 Tesla OMRI could be useful for free radical measurement for small samples.

  6. Blood brain barrier and brain tissue injury by Gd-DTPA in uremia-induced rabbits

    International Nuclear Information System (INIS)

    Choi, Sun Seob; Huh, Ki Yeong; Han, Jin Yeong; Lee, Yong Chul; Eun, Choong Gi; Yang, Yeong Il

    1996-01-01

    An experimental study was carried out to evaluate the morphological changes in the blood brain barrier and neighbouring brain tissue caused by Gd-DTPA in uremia-induced rabbits. Bilateral renal arteries and veins of ten rabbits were ligated. Gd-DTPA(0.2mmol/kg) was intravenously injected into seven rabbits immediately after ligation. After MRI, they were sacrificed 2 or 3 days after ligation in order to observe light and electron microscopic changes in the blood brain barrier and brain tissue. MRI findings were normal, except for enhancement of the superior and inferior sagittal sinuses on T1 weighted images in uremia-induced rabbits injected with Gd-DTPA. On light microscopic examination, these rabbits showed perivascular edema and glial fibrillary acidic protein expression: electron microscopic examination showed separation of tight junctions of endothelial cells, duplication/rarefaction of basal lamina, increased lysosomes of neurons with neuronal death, demyelination of myelin, and extravasation of red blood cells. Uremia-induced rabbits injected with Gd-DTPA showed more severe changes than those without Gd-DTPA injection. Injuries to the blood brain barrier and neighbouring brain tissue were aggravated by Gd-DTPA administration in uremia-induced rabbits. These findings appear to be associated with the neurotoxicity of Gd-DTPA

  7. Enhanced photoluminescence of Sm{sup 3+}/Bi{sup 3+} co-doped Gd{sub 2}O{sub 3} phosphors by combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guangsheng; Zhang Ying [Institute of Micro-system Physics, School of Physics and Electronics, Henan University, Kaifeng 475001 (China); Yin Jiang [Department of Physics, Nanjing University, Nanjing 210093 (China); Zhang, W.F. [Institute of Micro-system Physics, School of Physics and Electronics, Henan University, Kaifeng 475001 (China)], E-mail: wfzhang@henu.edu.cn

    2008-12-15

    Gd{sub 2}O{sub 3}:Sm{sup 3+} and Gd{sub 2}O{sub 3}:Sm{sup 3+},Bi{sup 3+} powders were prepared by a combustion method. Their structures were determined using X-ray diffraction. UV-visible absorption and photoluminescence spectra were investigated for Gd{sub 2}O{sub 3}:Sm{sup 3+} and Gd{sub 2}O{sub 3}:Sm{sup 3+},Bi{sup 3+} at different annealing temperatures and different doping concentrations. The emission spectra of all samples presented the characteristic emission narrow lines arising from the {sup 4}G{sub 5/2}{yields}{sup 6}H{sub J} transitions (J=5/2, 7/2, and 9/2) of Sm{sup 3+} ions upon excitation with UV irradiation. The emission intensity of Sm{sup 3+} ions was largely enhanced with introducing Bi{sup 3+} ions into Gd{sub 2}O{sub 3}:Sm{sup 3+} and the maximum occurred at a Bi{sup 3+} concentration of 0.5 mol%. The relevant mechanisms were discussed with the sensitization theory by Dexter and the aggregation behavior of Bi{sup 3+} ions.

  8. 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.)

  9. 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.)

  10. Remarkably enhanced photoluminescence of hexagonal GdPO4·nH2O:Eu with decreasing size

    International Nuclear Information System (INIS)

    Lu Shaozhe; Zhang Jiahua; Zhang Jishen; Zhao Haifeng; Luo Yongshi; Ren Xinguang

    2010-01-01

    The hexagonal rhabdophane-type GdPO 4 hydrate (GdPO 4 ·nH 2 O) was synthesized via a simple hydrothermal process. The size and morphology of the products can be tunable by adjusting the pH of reaction systems through the addition of aqueous NaOH. The nanorods with a width of 50-100 nm and a length of about 1 μm were obtained in the absence of NaOH (pH = 2), while a significant reduction of size (width: ∼ 10 nm, length: ∼ 50 nm) was observed for the product synthesized in the presence of NaOH (pH = 10). Surprisingly, the small-sized product exhibits a remarkably enhanced photoluminescence quantum yield and long excited state lifetime in comparison with those of the large-sized product. This abnormal luminescence phenomenon is discussed and explained. The EDS and XPS measurements revealed the presence of Na + in the small-sized samples. These Na + cations were probably bonded to the surface O 2- dangling bonds, which thus reduces the number of surface defects that usually serve as the nonradiative energy transfer center channels. A considerable reduction of surface defect centers results in the increase of the emission efficiency and excited state lifetime in a small-sized sample. Obviously, the controlled synthesis of rare-earth-doped nanoparticles with a small size, but with relatively strong luminescence, is significant for their applications in the areas of technologies including optoelectronics, sensing and bioimaging.

  11. 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

  12. Gd-DTPA-enhanced MR venography for varicose veins of the calf

    International Nuclear Information System (INIS)

    Kohata, Yoshiko; Naito, Akira; Ito, Katuhide.

    1995-01-01

    2D time-of-flight MR venography (2D TOF MRV) was performed in 16 patients (25 calves) with varicose veins and 2 volunteers (4 calves), and compared with venography. Sequential SPGR (TR/TE/FA=45 ms/7 ms/60deg) transverse images and/or GRASS (TR/TE/FA=100 ms/13 ms/60deg) transverse images were obtained for MRV. Superior presaturation pulse (S-SAT) was placed in 21 calves, and 0.05 mmol/kg Gd-DTPA was used in all calves. Projection MRVs were generated with maximum intensity projection (MIP) reconstruction. Regarding sequence parameter, S-SAT was useful to eliminate signal from artery that would obscure the signal of deep veins. The detectability of deep veins was improved with the use of S-SAT. In the comparison with venography, MRV could more clearly demonstrate varicose veins more than 5 mm in diameter and their drainage veins than venography. But it could not so clearly demonstrate deep veins as venography. It could not detect fine varicose veins less than 5 mm in diameter and connecting veins with valve insufficiency. In the examination of varicose veins, detection of deep veins, large varicose veins and their main drainage veins is clinically important, because diagnosis of patency of deep veins and dilatation of the drainage veins is necessary to choose the treatment, concluding conservative therapy, stripping and sclerotherapy. However, detection of fine varicose veins and connecting veins are not so important because those veins seldom need treatment. MRV was not so suitable for detection of deep veins, but very useful for detection of varicose veins more than 5 mm in diameter and their main drainage veins. In conclusion, MRV is non-invasive and effective method in varicose veins of calf, and it can take the place of venography with the improvement of deep vein detectability. (author)

  13. Pharmacokinetic changes induced by focused ultrasound in glioma-bearing rats as measured by dynamic contrast-enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Feng-Yi Yang

    Full Text Available Focused ultrasound (FUS combined with microbubbles has been shown to be a noninvasive and targeted drug delivery technique for brain tumor treatment. The purpose of this study was to measure the kinetics of Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA in glioma-bearing rats in the presence of FUS-induced blood-brain barrier disruption (BBB-D by magnetic resonance imaging (MRI. A total of ten glioma-bearing rats (9-12 weeks, 290-340 g were used in this study. Using dynamic contrast-enhanced (DCE-MRI, the spatial permeability of FUS-induced BBB-D was evaluated and the kinetic parameters were calculated by a general kinetic model (GKM. The results demonstrate that the mean Ktrans of the sonicated tumor (0.128±0.019 at 20 min and 0.103±0.023 at 24 h after sonication, respectively was significantly higher than (2.46-fold at 20 min and 1.78-fold at 24 h that of the contralateral (non-sonicated tumor (0.052±0.019 at 20 min and 0.058±0.012 at 24 h after sonication, respectively. In addition, the transfer constant Ktrans in the sonicated tumor correlated strongly with tissue EB extravasation (R = 0.95, which suggests that DCE-MRI may reflect drug accumulation in the brain. Histological observations showed no macroscopic damage except for a few small erythrocyte extravasations. The current study demonstrates that DCE-MRI can monitor the dynamics of the FUS-induced BBB-D process and constitutes a useful tool for quantifying BBB permeability in tumors.

  14. Studies of MRI relaxivities of gadolinium-labeled dendrons

    Science.gov (United States)

    Pan, Hongmu; Daniel, Marie-Christine

    2011-05-01

    In cancer detection, imaging techniques have a great importance in early diagnosis. The more sensitive the imaging technique and the earlier the tumor can be detected. Contrast agents have the capability to increase the sensitivity in imaging techniques such as magnetic resonance imaging (MRI). Until now, gadolinium-based contrast agents are mainly used for MRI, and show good enhancement. But improvement is needed for detection of smaller tumors at the earliest stage possible. The dendrons complexed with Gd(DOTA) were synthesized and evaluated as a new MRI contrast agent. The longitudinal and transverse relaxation effects were tested and compared with commercial drug Magnevist, Gd(DTPA).

  15. Comparison of AMI-25 enhanced MRI and helical dynamic CT in the detection of hepatic lesions

    International Nuclear Information System (INIS)

    Saitou, Kazuhiro; Matsuda, Hiromichi; Fukushima, Hiroaki; Kanzaki, Hiroshi; Hirose, Takashi; Karizaki, Dai; Abe, Kimihiko; Amino, Saburou

    1994-01-01

    We performed AMI-25 enhanced MRI and helical dynamic CT in 12 cases of hepatic lesions. Nine of these were hepatocellular carcinomas. Two cases were metastatic liver tumors (the primary lesion was gastric in one and the other was gallbladder cancer). One case was suspected to be adenomatous hyperplasia. Thirty-two lesions were detected in T2-weighted SE images before AMI-25 administration, while 46 lesions were detected in AMI-25 enhanced MRI images. In particular, AMI-25 enhanced MRI was superior to plain MRI in lesions less than 10 mm in size. A total of 48 lesions were detected in helical dynamic CT. Although AMI-25 enhanced MRI almost equaled helical dynamic CT in the detection of liver tumors, helical dynamic CT was slightly superior to AMI-25 enhanced MRI in the detection of subphrenic lesions. It was possible to know the hemodynamics in each hepatic lesion by helical dynamic CT. AMI-25 enhanced MRI was useful to know the inclusion of reticuloendothelial system, and that yielded different diagnoses in adenomatous hyperplasia and well differentiated hepatocellular carcinoma. Helical dynamic CT was useful for qualitative diagnosis. Both AMI-25 enhanced MRI and helical dynamic CT contributed to the detection of liver tumor and qualitative diagnosis. (author)

  16. Rheumatoid arthritis of the wrist; Dynamic Gd-DTPA enhanced MRT. Rheumatoide Arthritis des Handgelenkes; Dynamische Gd-DTPA-verstaerkte MRT

    Energy Technology Data Exchange (ETDEWEB)

    Naegele, M. (Radiologische Universitaetsklinik, Bonn (Germany)); Kunze, V. (Radiologische Universitaetsklinik, Bonn (Germany)); Koch, W. (Orthopaedische Universitaetsklinik, Bonn (Germany)); Bruening, R. (Radiologische Universitaetsklinik, Bonn (Germany)); Seelos, K. (Radiologische Universitaetsklinik, Bonn (Germany)); Stroehmann, I. (Radiologische Universitaetsklinik, Bonn (Germany)); Woell, B. (Radiologische Universitaetsklinik, Bonn (Germany)); Reiser, M. (Radiologische Universitaetsklinik, Bonn (Germany))

    1993-02-01

    21 patients with rheumatoid arthritis of the wrist diagnosed according to the criteria of the American Rheumatism Association were examined by dynamic MRT before and after the i.v. injection of Gd-DTPA (0.1 mmol/kg). The results were correlated with the clinical and radiological findings. The increased signal intensity of the pannus was 1.17[+-]0.45%/sec and this differed significantly (p<0.001) from bone marrow (0.16[+-]0.11%/sec) and from muscle (0.25[+-]0.16%/sec). Blood sedimentation rate correlated with the gradient of synovial proliferation (p<0.05). There were no further statistically significant correlations between the clinical, radiological and MRT findings and the change in signal intensity from synovial proliferation as shown by dynamic MRT. (orig.)

  17. The Impact of Gd-Eob-Dtpa-Enhanced MR Cholangiography in Biliary Diseases: Comparison with T2-Weighted MR Cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Evrim Özmen

    2016-06-01

    Full Text Available Background: Contrast enhanced magnetic resonance cholangiography is a novel technique and promising method in demonstrating biliary tree anatomy and evaluating biliary disorders. However, to date, there are a limited number of studies that have focused on the impact of this technique. Aims: We aimed to evaluate the additional role of contrast enhanced MR cholangiography (MRC and compare contrast enhanced MRC with T2-weighted (w magnetic resonance cholangiopancreatography (MRCP in the diagnosis of biliary disorders. Study Design: Diagnostic accuracy study. Methods: The T2w-MRCP and contrast enhanced MRC sequences of 31 patients whose gold standard test results were available were scored visually for the existence of pathological findings with regard to any of the biliary diseases. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA was used as the contrast agent. The correlation values were determined according to the statistical analysis made from those scores and the sensitivity, specificity and accuracy values of each sequence were detected as well. Results: We detected that the correlation values with gold standard methods of contrast enhanced MRC sequences were significantly higher than the ones of T2w-MRCP sequences. The correlation ratios of T2w-MRCP sequences were between 26 and 34%, while those for contrast enhanced MRC sequences were between 81 and 83% for the first reader and the correlation ratios of T2w-MRCP sequences were between 10 and 61%, whereas those of contrast enhanced MRC were between 79 and 81% for the second reader The mean sensitivity, specificity and accuracy values of T2w-MRCP sequences were 14.3-42.5%, 85-89.2% and 59.3-72.5%, respectively, while the mean sensitivity, specificity and accuracy values of contrast enhanced MRC sequences were 100%, 86.7% and 93.2-93.3%, respectively. Conclusion: We suggest that obtaining of contrast enhanced MRC sequences in addition to the T2w-MRCP can be useful in

  18. Correlation of MRI and clinical features in meningeal carcinomatosis

    International Nuclear Information System (INIS)

    Watanabe, M.; Tanaka, R.; Takeda, N.

    1993-01-01

    Ten patients with meningeal carcinomatosis associated with nonhaemoatological neoplasms were examined: Six with breast, two with gastrointestinal and one with lung cancer, plus one with a tumour of unknown origin. Cytology was positive in all but one. The patients were classified into four groups according to the gadolinium-enhanced MRI (Gd-MRI) appearances: Group 1 had pure leptomeningeal carcinomatosis, group 2 dural carcinomatosis, group 3 spinal leptomeningeal carcinomatosis, and group 4 had normal Gd-MRI except for hydrocephalus. In group 1, Gd-MRI showed diffuse enhancement of the subarachnoid space, including the cisterns around the midbrain, the sylvian fissures, or cerebellar and cerebral sulci. In group 2, Gd-MRI showed diffuse, thick, partially nodular enhancement of the dura mater. No leptomeningeal or subependymal enhancement was evident. In group 3, nodular masses were seen only in the spinal canal. In group 4, no definite evidence of meningeal carcinomatosis was demonstrated on contrast-enhanced CT (CE-CT) or Gd-MRI. The median survival time was 2.0 months in group 1, 1.0 month in group 3, and 4.5 months in group 4, but the two patients in group 2 were alive 10 and 15 months after a definite diagnosis of meningeal carcinomatosis was made. In all patients examined by both CE-CT and Gd-MRI, the latter was superior for identification of meningeal carcinomatosis. Hydrocephalus is an important indirect sign of leptomeningeal carcinomatosis, but was not seen in patients with dural carcinomatosis despite the presence of increased intracranial pressure. (orig.)

  19. Development of Bifunctional Gadolinium-Labeled Superparamagnetic Nanoparticles (Gd-MnMEIO for In Vivo MR Imaging of the Liver in an Animal Model.

    Directory of Open Access Journals (Sweden)

    Yu-Ting Kuo

    Full Text Available Liver tumors are common and imaging methods, particularly magnetic resonance imaging (MRI, play an important role in their non-invasive diagnosis. Previous studies have shown that detection of liver tumors can be improved by injection of two different MR contrast agents. Here, we developed a new contrast agent, Gd-manganese-doped magnetism-engineered iron oxide (Gd-MnMEIO, with enhancement effects on both T1- and T2-weighted MR images of the liver. A 3.0T clinical MR scanner equipped with transmit/receiver coil for mouse was used to obtain both T1-weighted spoiled gradient-echo and T2-weighted fast spin-echo axial images of the liver before and after intravenous contrast agent injection into Balb/c mice with and without tumors. After pre-contrast scanning, six mice per group were intravenously injected with 0.1 mmol/kg Gd-MnMEIO, or the control agents, i.e., Gd-DTPA or SPIO. The scanning time points for T1-weighted images were 0.5, 5, 10, 15, 20, 25, and 30 min after contrast administration. The post-enhanced T2-weighted images were then acquired immediately after T1-weighted acquisition. We found that T1-weighted images were positively enhanced by both Gd-DTPA and Gd-MnMEIO and negatively enhanced by SPIO. The enhancement by both Gd-DTPA and Gd-MnMEIO peaked at 0.5 min and gradually declined thereafter. Gd-MnMEIO (like Gd-DTPA enhanced T1-weighted images and (like SPIO T2-weighted images. Marked vascular enhancement was clearly visible on dynamic T1-weighted images with Gd-MnMEIO. In addition, the T2 signal was significantly decreased at 30 min after administration of Gd-MnMEIO. Whereas the effects of Gd-MnMEIO and SPIO on T2-weighted images were similar (p = 0.5824, those of Gd-MnMEIO and Gd-DTPA differed, with Gd-MnMEIO having a significant T2 contrast effect (p = 0.0086. Our study confirms the feasibility of synthesizing an MR contrast agent with both T1 and T2 shortening effects and using such an agent in vivo. This agent enables tumor

  20. Room temperature magnetic ordering, enhanced magnetization and exchange bias of GdMnO_3 nanoparticles in (GdMnO_3)_0_._7_0(CoFe_2O_4)_0_._3_0

    International Nuclear Information System (INIS)

    Mitra, A.; Mahapatra, A.S.; Mallick, A.; Chakrabarti, P.K.

    2017-01-01

    Nanoparticles of GdMnO_3 (GMO) are prepared by sol-gel method. To enhance the magnetic property and also to obtain the magnetic ordering at room temperature (RT), nanoparticles of GMO are incorporated in the matrix of CoFe_2O_4 (CFO). Desired crystallographic phases of CFO, GMO and GMO-CFO are confirmed by analyzing X-ray diffractrograms (XRD) using Rietveld method. The average size of nanoparticles and their distribution, crystallographic phase, nanocrystallinity etc. are studied by high-resolution transmission electron microscope (HRTEM). Magnetic hysteresis loops (M-H) of GMO-CFO under zero field cooled (ZFC) and field cooled (FC) conditions are observed at different temperatures down to 5 K. Magnetization vs. temperature (M-T) under ZFC and FC conditions are also recorded. Interestingly, exchange bias (EB) is found at low temperature which suggests the encapsulation of the ferromagnetic (FM) nanoparticles of GMO by the ferrimagnetic nanoparticles of CFO below ~100 K. Enhanced magnetization, EB effect and RT magnetic ordering of GMO-CFO would be interesting for both theoretical and experimental investigations. - Highlights: • Nanoparticles of GdMnO_3 are incorporated in the matrix of CoFe_2O_4. • RT magnetic ordering of GMO nanoparticles in GMO-CFO is observed. • Magnetic property of GMO-CFO is highly enhanced compared to GMO. • Exchange bias is found in GMO-CFO at low temperature.

  1. Dynamic glucose enhanced (DGE) MRI for combined imaging of blood-brain barrier break down and increased blood volume in brain cancer.

    Science.gov (United States)

    Xu, Xiang; Chan, Kannie W Y; Knutsson, Linda; Artemov, Dmitri; Xu, Jiadi; Liu, Guanshu; Kato, Yoshinori; Lal, Bachchu; Laterra, John; McMahon, Michael T; van Zijl, Peter C M

    2015-12-01

    Recently, natural d-glucose was suggested as a potential biodegradable contrast agent. The feasibility of using d-glucose for dynamic perfusion imaging was explored to detect malignant brain tumors based on blood brain barrier breakdown. Mice were inoculated orthotopically with human U87-EGFRvIII glioma cells. Time-resolved glucose signal changes were detected using chemical exchange saturation transfer (glucoCEST) MRI. Dynamic glucose enhanced (DGE) MRI was used to measure tissue response to an intravenous bolus of d-glucose. DGE images of mouse brains bearing human glioma showed two times higher and persistent changes in tumor compared with contralateral brain. Area-under-curve (AUC) analysis of DGE delineated blood vessels and tumor and had contrast comparable to the AUC determined using dynamic contrast enhanced (DCE) MRI with GdDTPA, both showing a significantly higher AUC in tumor than in brain (P blood volume and permeability with respect to normal brain. We expect DGE will provide a low-risk and less expensive alternative to DCE MRI for imaging cancer in vulnerable populations, such as children and patients with renal impairment. © 2015 Wiley Periodicals, Inc.

  2. Dynamic Glucose Enhanced (DGE) MRI for Combined Imaging of Blood Brain Barrier Break Down and Increased Blood Volume in Brain Cancer

    Science.gov (United States)

    Xu, Xiang; Chan, Kannie WY; Knutsson, Linda; Artemov, Dmitri; Xu, Jiadi; Liu, Guanshu; Kato, Yoshinori; Lal, Bachchu; Laterra, John; McMahon, Michael T.; van Zijl, Peter C.M.

    2015-01-01

    Purpose Recently, natural d-glucose was suggested as a potential biodegradable contrast agent. The feasibility of using d-glucose for dynamic perfusion imaging was explored to detect malignant brain tumors based on blood brain barrier breakdown. Methods Mice were inoculated orthotopically with human U87-EGFRvIII glioma cells. Time-resolved glucose signal changes were detected using chemical exchange saturation transfer (glucoCEST) MRI. Dynamic glucose enhanced (DGE) MRI was used to measure tissue response to an intravenous bolus of d-glucose. Results DGE images of mouse brains bearing human glioma showed two times higher and persistent changes in tumor compared to contralateral brain. Area-under-curve (AUC) analysis of DGE delineated blood vessels and tumor and had contrast comparable to the AUC determined using dynamic contrast enhanced (DCE) MRI with GdDTPA, both showing a significantly higher AUC in tumor than in brain (pblood volume and permeability with respect to normal brain. We expect DGE will provide a low-risk and less expensive alternative to DCE MRI for imaging cancer in vulnerable populations, such as children and patients with renal impairment. PMID:26404120

  3. In Vivo Evaluation of the Visual Pathway in Streptozotocin-Induced Diabetes by Diffusion Tensor MRI and Contrast Enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Swarupa Kancherla

    Full Text Available Visual function has been shown to deteriorate prior to the onset of retinopathy in some diabetic patients and experimental animal models. This suggests the involvement of the brain's visual system in the early stages of diabetes. In this study, we tested this hypothesis by examining the integrity of the visual pathway in a diabetic rat model using in vivo multi-modal magnetic resonance imaging (MRI. Ten-week-old Sprague-Dawley rats were divided into an experimental diabetic group by intraperitoneal injection of 65 mg/kg streptozotocin in 0.01 M citric acid, and a sham control group by intraperitoneal injection of citric acid only. One month later, diffusion tensor MRI (DTI was performed to examine the white matter integrity in the brain, followed by chromium-enhanced MRI of retinal integrity and manganese-enhanced MRI of anterograde manganese transport along the visual pathway. Prior to MRI experiments, the streptozotocin-induced diabetic rats showed significantly smaller weight gain and higher blood glucose level than the control rats. DTI revealed significantly lower fractional anisotropy and higher radial diffusivity in the prechiasmatic optic nerve of the diabetic rats compared to the control rats. No apparent difference was observed in the axial diffusivity of the optic nerve, the chromium enhancement in the retina, or the manganese enhancement in the lateral geniculate nucleus and superior colliculus between groups. Our results suggest that streptozotocin-induced diabetes leads to early injury in the optic nerve when no substantial change in retinal integrity or anterograde transport along the visual pathways was observed in MRI using contrast agent enhancement. DTI may be a useful tool for detecting and monitoring early pathophysiological changes in the visual system of experimental diabetes non-invasively.

  4. International investigation of breast MRI: results of a multicentre study (11 sites) concerning diagnostic parameters for contrast-enhanced MRI based on 519 histopathologically correlated lesions

    International Nuclear Information System (INIS)

    Heywang-Koebrunner, S.H.; Bick, U.; Bradley, W.G. Jr.; Bone, B.; Casselman, J.; Coulthard, A.; Fischer, U.; Mueller-Schimpfle, M.; Oellinger, H.; Patt, R.; Teubner, J.; Friedrich, M.; Newstead, G.; Holland, R.; Schauer, A.; Sickles, E.A.; Tabar, L.; Waisman, J.; Wernecke, K.D.

    2001-01-01

    A multicentre study was undertaken to provide fundamentals for improved standardization and optimized interpretation guidelines of dynamic contrast-enhanced MRI. Only patients scheduled for biopsy of a clinical or imaging abnormality were included. They underwent standardized dynamic MRI on Siemens 1.0 (163 valid lesions ≥ 5 mm) or 1.5 T (395 valid lesions ≥ 5 mm) using 3D fast low-angle shot (FLASH; 87 s) before and five times after standardized bolus of 0.2 mmol Gd-DTPA/kg. One-Tesla and 1.5 T data were analysed separately using a discriminant analysis. Only histologically correlated lesions entered the statistical evaluation. Histopathology and imaging were correlated in retrospect and in open. The best results were achieved by combining up to five wash-in or wash-out parameters. Different weighting of false-negative vs false-positive calls allowed formulation of a statistically based interpretation scheme yielding optimized rules for the highest possible sensitivity (specificity 30 %), for moderate (50 %) or high (64-71 %) specificity. The sensitivities obtained at the above specificity levels were better at 1.0 T (98, 97, or 96 %) than at 1.5 T (96, 93, 86 %). Using a widely available standardized MR technique definition of statistically founded interpretation rules is possible. Choice of an optimum interpretation rule may vary with the clinical question. Prospective testing remains necessary. Differences of 1.0 and 1.5 T are not statistically significant but may be due to pulse sequences (orig.)

  5. International investigation of breast MRI: results of a multicentre study (11 sites) concerning diagnostic parameters for contrast-enhanced MRI based on 519 histopathologically correlated lesions

    Energy Technology Data Exchange (ETDEWEB)

    Heywang-Koebrunner, S.H. [Dept. of Diagnostic Radiology, Univ. Hospital Halle (Germany); Bick, U. [Dept. of Diagnostic Radiology, Westphalian Wilhelms Univ., Muenster (Germany); Bradley, W.G. Jr. [Memorial Medical Center, Long Beach, CA (United States); Bone, B. [Dept. of Diagnostic Radiology, Huddinge Univ., Stockholm (Sweden); Casselman, J. [Dept. of Diagnostic Radiology, Brugge (Belgium); Coulthard, A. [Dept. of Diagnostic Radiology, Royal Victoria Infirmary, Newcastle (United Kingdom); Fischer, U. [Dept. of Diagnostic Radiology, Georg August University, Goettingen (Germany); Mueller-Schimpfle, M. [Dept. of Diagnostic Radiology, Eberhard Karls University, Tuebingen (Germany); Oellinger, H. [Dept. of Diagnostic Radiology, Rudolph Virchow Univ. Clinic, Berlin (Germany); Patt, R. [Dept. of Diagnostic Radiology, Georgetown Univ., Washington, DC (United States); Teubner, J. [Dept. of Diagnostic Radiology, Mannheim Clinic, Heidelberg Univ. (Germany); Friedrich, M. [Dept. of Diagnostic Radiology, Urban Hospital, Berlin (Germany); Newstead, G. [Faculty Practice Radiology, New York Univ., NY (United States); Holland, R. [Dept. of Pathology, Univ. Hospital Nijmegen (Netherlands); Schauer, A. [Dept. of Pathology, Georg August Univ., Goettingen (Germany); Sickles, E.A. [Dept. of Radiology, University of California, San Francisco (United States); Tabar, L. [Falun Central Hospital, Falun (Sweden); Waisman, J. [Dept. of Pathology, New York University, NY (United States); Wernecke, K.D. [Inst. of Medical Biometrics, University Charite, Berlin (Germany)

    2001-04-01

    A multicentre study was undertaken to provide fundamentals for improved standardization and optimized interpretation guidelines of dynamic contrast-enhanced MRI. Only patients scheduled for biopsy of a clinical or imaging abnormality were included. They underwent standardized dynamic MRI on Siemens 1.0 (163 valid lesions {>=} 5 mm) or 1.5 T (395 valid lesions {>=} 5 mm) using 3D fast low-angle shot (FLASH; 87 s) before and five times after standardized bolus of 0.2 mmol Gd-DTPA/kg. One-Tesla and 1.5 T data were analysed separately using a discriminant analysis. Only histologically correlated lesions entered the statistical evaluation. Histopathology and imaging were correlated in retrospect and in open. The best results were achieved by combining up to five wash-in or wash-out parameters. Different weighting of false-negative vs false-positive calls allowed formulation of a statistically based interpretation scheme yielding optimized rules for the highest possible sensitivity (specificity 30 %), for moderate (50 %) or high (64-71 %) specificity. The sensitivities obtained at the above specificity levels were better at 1.0 T (98, 97, or 96 %) than at 1.5 T (96, 93, 86 %). Using a widely available standardized MR technique definition of statistically founded interpretation rules is possible. Choice of an optimum interpretation rule may vary with the clinical question. Prospective testing remains necessary. Differences of 1.0 and 1.5 T are not statistically significant but may be due to pulse sequences (orig.)

  6. Gadolinium contrast-enhanced MRI sequence does not have an incremental value in the assessment of sacroiliitis in patients with early inflammatory back pain by using MRI in combination with pelvic radiographs: a 2-year follow-up study

    NARCIS (Netherlands)

    van Onna, M.; van Tubergen, A.; van der Heijde, D.; Jurik, A. G.; Landewé, R.

    2014-01-01

    To evaluate the potential incremental value in detecting sacroiliitis of the T1 post-gadolinium diethylenetriaminepenta-acetic acid (Gd-DTPA) MRI sequence of the sacroiliac joints (SIJ) compared with the combination of short tau inversion recovery (STIR) MRI sequence and pelvic radiographs in

  7. Early-enhancing non-neoplastic lesions on gadolinium-enhanced MRI of the liver

    Energy Technology Data Exchange (ETDEWEB)

    Kanematsu, M. E-mail: masa-gif@umin.ac.jp; Kondo, H.; Semelka, R.C.; Matsuo, M.; Goshima, S.; Hoshi, H.; Moriyama, N.; Itai, Y

    2003-10-01

    AIM: To assess the frequency, cause, and significance of early-enhancing, non-neoplastic (EN) lesions on gadolinium-enhanced magnetic resonance imaging (MRI) of the liver performed for the detection of malignant hepatic tumours. MATERIALS AND METHODS: From September 1997 to September 2000, we reviewed the images of 125 patients, suspected of having hepatic tumours, in whom (1) gadolinium-enhanced triphasic dynamic gradient-recalled-echo (GRE) imaging in addition to unenhanced T1- and T2-weighted MRI was performed, (2) conventional angiography and combination computed tomography (CT) hepatic arteriography and CT during arterial portography were performed within 2 weeks of the MRI, and (3) definitive surgery within 2 weeks of the MRI or follow-up study by means of intravenously contrast-enhanced CT or MRI in 10 months or more was performed. Angiographic studies were correlated to determine the underlying causes of the EN lesions. RESULTS: We found 78 EN lesions in 36 patients (29%), ranging in size from 4 and 50 mm (mean, 12.2 mm). From the MR reports, our radiologists had prospectively diagnosed EN lesions as probable malignant tumours in eight (10%), possible malignant tumours in 36 (46%), and probable non-neoplastic lesion in 34 (44%). EN lesions were found in 27 of 81 (33%) cirrhotic patients and in nine of 44 (20%) non-cirrhotic patients. Fifty-one EN lesions (65%) were located along the liver edge. The shape was circular in 42 (54%), oval in 14 (18%), irregular in 12 (15%), wedge-shaped in seven (9%), and fan-shaped in three (4%). Twenty EN lesions (26%) appeared slightly hyperintense on T2-weighted images. The causes were non-neoplastic arterio-portal shunting in 48 (62%), cystic venous drainage in four (5%), rib compression in four (5%), aberrant right gastric venous drainage in two (3%), and unknown in 20 (26%). CONCLUSION: Over half the number of EN lesions were caused by non-neoplastic arterio-portal shunting, occasionally showing slight hyperintensity on

  8. Quantitative MR changes in Gd-DTPA enhancement after high dose intravenous methylprednisolone in multiple sclerosis

    International Nuclear Information System (INIS)

    Barkhof, F.; Valk, J.; Hommes, O.R.; Scheltens, P.

    1991-01-01

    The purpose of this study was to investigate the effect of high dose intravenous methylprednisolone (MP) on gadolinium-DTPA enhancement in MS-lesions. By means of this the influence of MP on the permeability of the blood-brain barrier can be studied. (author). 19 refs.; 1 fig

  9. Contrast Enhancement of the Brain by Folate-Conjugated Gadolinium–Diethylenetriaminepentaacetic Acid–Human Serum Albumin Nanoparticles by Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Huedayi Korkusuz

    2012-07-01

    Full Text Available Different from regular small molecule contrast agents, nanoparticle-based contrast agents have a longer circulation time and can be modified with ligands to confer tissue-specific contrasting properties. We evaluated the tissue distribution of polymeric nanoparticles (NPs prepared from human serum albumin (HSA, loaded with gadolinium–diethylenetriaminepentaacetic acid (Gd-DTPA (Gd-HSA-NP, and coated with folic acid (FA (Gd-HSA-NP-FA in mice by magnetic resonance imaging (MRI. FA increases the affinity of the Gd-HSA-NP to FA receptor–expressing cells. Clinical 3 T MRI was used to evaluate the signal intensities in the different organs of mice injected with Gd-DTPA, Gd-HSA-NP, or Gd-HSA-NP-FA. Signal intensities were measured and standardized by calculating the signal to noise ratios. In general, the NP-based contrast agents provided stronger contrasting than Gd-DTPA. Gd-HSA-NP-FA provided a significant contrast enhancement (CE in the brain (p = .0032, whereas Gd-DTPA or Gd-HSA-NP did not. All studied MRI contrast agents showed significant CE in the blood, kidney, and liver (p < .05. Gd-HSA-NP-FA elicited significantly higher CE in the blood than Gd-HSA-NP (p = .0069; Gd-HSA-NP and Gd-HSA-NP-FA did not show CE in skeletal muscle and gallbladder; Gd-HSA-NP, but not Gd-HSA-NP-FA, showed CE in the cardiac muscle. Gd-HSA-NP-FA has potential as an MRI contrast agent in the brain.

  10. Gadolinium-enhanced dynamic magnetic resonance imaging with endorectal coil for local staging of rectal cancer

    International Nuclear Information System (INIS)

    Tamakawa, Mitsuharu; Kawaai, Yuriko; Shirase, Ryuji

    2010-01-01

    The aim of this study was to evaluate the accuracy of dynamic gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) with endorectal coil for assessing tumor invasion based on simple classification criteria. A total of 58 patients with operable primary rectal cancer underwent preoperative MRI. An enhancement pattern in Gd-enhanced dynamic MRI with regard to tumor penetration was clarified. Retrospectively, two observers independently scored T2-weighted MRI and T2-weighted MRI combined with Gd-enhanced dynamic MRI for tumor penetration using the following criteria: With Gd-enhanced dynamic MRI, T1 tumors showed an early enhanced line around the tumor as rim enhancement; T2 tumors appeared as black lines or double layers, as the muscularis propria kept its integrity; T3 tumors showed partial discontinuity of the muscularis propria as a dotted line and a perforated area as an interrupted line. A confidence level scoring system was used, and receiver operating characteristic curves were generated. There were no significant differences at the T1 stage. There were significant differences for observer 1 (P=0.001 for observer 1) at the T2 stage. There were significant differences for both observers (P=0.001 for observer 1 and P=0.005 for observer 2) at the T3 stage. Our criteria for Gd-enhanced dynamic MRI were effective for T3 stage tumors. (author)

  11. Low flip angle spin-echo MR imaging to obtain better Gd-DTPA enhanced imaging with ECG gating

    International Nuclear Information System (INIS)

    Sugimura, Kazuro; Kawamitsu, Hideaki; Yoshikawa, Kazuaki; Kasai, Toshifumi; Yuasa, Koji; Ishida, Tetsuya

    1992-01-01

    ECG-gated spin-echo imaging (ECG-SE) can reduce physiological motion artifact. However, ECG-SE does not provide strong T1-weighted images because repetition time (TR) depends on heart rate (HR). We investigated the usefulness of low flip angle spin-echo imaging (LFSE) in obtaining more T1-dependent contrast with ECG gating. In computer simulation, the predicted image contrast and single-to-noise ratio (SNR) obtained for each flip angle (0-180deg) and each TR (300 msec-1200 msec) were compared with those obtained by conventional T1-weighted spin-echo imaging (CSE: TR=500 msec, TE=20 msec). In clinical evaluation, tissue contrast [contrast index (CI): (SI of lesion-SI of muslce) 2* 100/SI of muscle] obtained by CSE and LFSE were compared in 17 patients. At a TR of 1,000 msec, T1-dependent contrast increased with decreasing flip angle and that at 38deg was identical to that with T1-weighted spin-echo. SNR increased with the flip angle until 100deg, and that at 53deg was identical to that with T1-weighted spin-echo. CI on LFSE (74.0±52.0) was significantly higher than CI on CSE (40.9±35.9). ECG-gated LFSE imaging provides better T1-dependent contrast than conventional ECG-SE. This method was especially useful for Gd-DTPA enhanced MR imaging. (author)

  12. 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

  13. Optimizing Water Exchange Rates and Rotational Mobility for High-Relaxivity of a Novel Gd-DO3A Derivative Complex Conjugated to Inulin as Macromolecular Contrast Agents for MRI.

    Science.gov (United States)

    Granato, Luigi; Vander Elst, Luce; Henoumont, Celine; Muller, Robert N; Laurent, Sophie

    2018-02-01

    Thanks to the understanding of the relationships between the residence lifetime τ M of the coordinated water molecules to macrocyclic Gd-complexes and the rotational mobility τ R of these structures, and according to the theory for paramagnetic relaxation, it is now possible to design macromolecular contrast agents with enhanced relaxivities by optimizing these two parameters through ligand structural modification. We succeeded in accelerating the water exchange rate by inducing steric compression around the water binding site, and by removing the amide function from the DOTA-AA ligand [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid mono(p-aminoanilide)] (L) previously designed. This new ligand 10[2(1-oxo-1-p-propylthioureidophenylpropyl]-1,4,7,10-tetraazacyclodecane-1,4,7-tetraacetic acid (L 1 ) was then covalently conjugated to API [O-(aminopropyl)inulin] to get the complex API-(GdL 1 )x with intent to slow down the rotational correlation time (τ R ) of the macromolecular complex. The evaluation of the longitudinal relaxivity at different magnetic fields and the study of the 17 O-NMR at variable temperature of the low-molecular-weight compound (GdL 1 ) showed a slight decrease of the τ M value (τM310 = 331 ns vs. τM310 = 450 ns for the GdL complex). Consequently to the increase of the size of the API-(GdL 1 )x complex, the rotational correlation time becomes about 360 times longer compared to the monomeric GdL 1 complex (τ R  = 33,700 ps), which results in an enhanced proton relaxivity. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  14. Gd{sub 90}Co{sub 2.5}Fe{sub 7.5} alloy displaying enhanced magnetocaloric properties

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, V., E-mail: virgil12@nist.gov [Materials Science and Engineering Division, NIST, Gaithersburg, MD 20899-8552 (United States); Shull, R.D., E-mail: robert.shull@nist.gov [Materials Science and Engineering Division, NIST, Gaithersburg, MD 20899-8552 (United States); Kletetschka, G., E-mail: kletetschka@gmail.com [Faculty of Science, Charles University, Prague 12843 (Czech Republic); Institute of Geology, Academy of Science of the Czech Republic, v.v.i., Prague 16500 (Czech Republic); Stutzman, P.E., E-mail: paul.stutzman@nist.gov [Materials and Structural Systems Division, NIST, Gaithersburg, MD 20899-861 (United States)

    2015-02-15

    Highlights: • The Gd{sub 90}Co{sub 2.5}Fe{sub 7.5} alloy displays superior magnetocaloric properties than Gd. • Alloy’s superior properties at relatively low field values: 400, 800 kA/m (0.5, 1 T). • We proposed two possible mechanisms for the Gd-based alloy enhanced properties. • We indicated a pathway for further improving the alloy magnetocaloric properties. - Abstract: We report on the discovery of a new Gd{sub 90}Co{sub 2.5}Fe{sub 7.5} alloy exhibiting superior magnetocaloric properties compared to those of gadolinium. We present magnetically-derived entropy change, ΔS{sub M}, computed from magnetic data, and thermally-derived temperature change, ΔT{sub ad}, obtained from direct thermal measurements together with their respective MCE peaks for the alloy and gadolinium. The MCE peaks of the alloy are taller and broader than the corresponding MCE peaks of gadolinium. Correspondingly, the refrigeration capacity (RC) values of the alloy computed from magnetic and thermal MCEs for field changes, ΔH, of 400 kA/m (0.5 T) and 800 kA/m (1 T) are about 20% larger than those of gadolinium. Two possible mechanisms are proposed to account for the improved magnetocaloric properties of gadolinium alloyed with small amounts of Co and Fe, thereby pointing out a different methodology to use in the search for improved low field magnetic refrigerants.

  15. Comparison of acquisition time and dose for late gadolinium enhancement imaging at 3.0 T in patients with chronic myocardial infarction using Gd-BOPTA

    International Nuclear Information System (INIS)

    Doltra, A.; Skorin, A.; Gebker, R.; Klein, C.; Fleck, E.; Kelle, S.; Hamdan, A.; Schnackenburg, B.; Nagel, E.

    2014-01-01

    To compare contrast doses and acquisition times for late gadolinium enhancement (LGE) imaging at 3.0 T using gadobenate dimeglumine (Gd-BOPTA) in patients with chronic myocardial infarction. Thirty-four patients with chronic myocardial infarction were randomised to 0.10, 0.15 and 0.20 mmol/kg of Gd-BOPTA. T1-weighted inversion recovery gradient echo sequences were performed at 5, 10, 15 and 20 min post-administration of contrast in a 3.0-T scanner. Scar-to-myocardium contrast-to-noise ratio (CNR), scar-to-blood CNR, scar size and image quality were assessed. Imaging at 5 min was associated with a lower scar-to-blood CNR in comparison to 10, 15 and 20 min at 0.10 mmol/kg, and in comparison to 15 and 20 min at 0.20 mmol/kg. At 0.10-mmol/kg, imaging at 5 min yielded smaller infarct sizes in comparison to 15 and 20 min. Finally, at 0.20-mmol/kg, imaging at 5 min was associated with poorer image quality in comparison to later times. In LGE imaging at 3.0 T, low doses of Gd-BOPTA perform equally well as higher doses. Early acquisition (5 min) is associated with lower infarct sizes and image quality. Studies with sufficient diagnostic quality can be obtained after 10 min using 0.10 mmol/kg Gd-BOPTA. (orig.)

  16. An experimental study on renal functional disturbance in rabbits after acute ureteral obstruction with dynamic Gd-DTPA enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kyoung Ja [Seoul Red Cross Hospital, Seoul (Korea, Republic of); Chung, Eun Chul; Rlee, Chung Sik [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

    1994-05-15

    To evaluate the anatomic and functional change in acutely obstructed kidneys, and probability of functional recovery after resolving the obstruction. There were 5 animal groups (6 rabbits in each group)-normal control group, 4 acute ureteral obstruction group. Each of the latter group was imaged with Gd-DTPA enhanced dynamic MR 2, 6, 24, and 48 hours after ligation of the left proximal urter, respectively. We compared the findings of dynamic MR imaging and histopathological findings. We could observe centripetal movement of dark band pattern which could be defined as 3 phases renal cortex, outer medulla, and inner medulla in normal rabbits. The appearance of the dark band pattern was delayed or absent in ureteral obstruction group with linear relationship to the duration of the obstruction. Gd-DTPA enhanced MR can be used to differentiate acute obstructive nephropathy from other causes of nephropathy and foretell the prognosis of the obstruction.

  17. An experimental study on renal functional disturbance in rabbits after acute ureteral obstruction with dynamic Gd-DTPA enhanced MR imaging

    International Nuclear Information System (INIS)

    Shin, Kyoung Ja; Chung, Eun Chul; Rlee, Chung Sik

    1994-01-01

    To evaluate the anatomic and functional change in acutely obstructed kidneys, and probability of functional recovery after resolving the obstruction. There were 5 animal groups (6 rabbits in each group)-normal control group, 4 acute ureteral obstruction group. Each of the latter group was imaged with Gd-DTPA enhanced dynamic MR 2, 6, 24, and 48 hours after ligation of the left proximal urter, respectively. We compared the findings of dynamic MR imaging and histopathological findings. We could observe centripetal movement of dark band pattern which could be defined as 3 phases renal cortex, outer medulla, and inner medulla in normal rabbits. The appearance of the dark band pattern was delayed or absent in ureteral obstruction group with linear relationship to the duration of the obstruction. Gd-DTPA enhanced MR can be used to differentiate acute obstructive nephropathy from other causes of nephropathy and foretell the prognosis of the obstruction

  18. Synthesis and evaluation of nanoglobule-cystamine-(Gd-DO3A, a biodegradable nanosized magnetic resonance contrast agent for dynamic contrast-enhanced magnetic resonance urography

    Directory of Open Access Journals (Sweden)

    Rongzuo Xu

    2010-09-01

    Full Text Available Rongzuo Xu1, Todd Lyle Kaneshiro1, Eun-Kee Jeong2, Dennis L Parker2, Zheng-Rong Lu31Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, USA; 2Department of Radiology, University of Utah, Salt Lake City, UT, USA; 3Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USAAbstract: Dynamic contrast-enhanced magnetic resonance imaging has been recently shown to be effective for diagnostic urography. High-resolution urographic images can be acquired with T1 contrast agents for the kidney and urinary tract with minimal noise in the abdomen. Currently, clinical contrast agents are low molecular weight agents and can rapidly extravasate from blood circulation, leading to slow contrast agent elimination through kidney and consequently providing limited contrast enhancement in urinary tract. In this study, a new biodegradable macromolecular contrast agent, nanoglobule-G4-cystamine-(Gd-DO3A, was prepared by conjugating Gd-DO3A chelates on the surface of a generation 4 nanoglobule, poly-l-lysine octa(3-aminopropylsilsesquioxane dendrimer, via a disulfide spacer, where the carrier had a precisely defined nanosize that is far smaller than the renal filtration threshold. The in vivo contrast enhancement and dynamic imaging of the urinary tract of the agent was evaluated in nude mice using a low molecular weight agent Gd(DTPA-BMA as a control. The agent eliminated rapidly from blood circulation and accumulated more abundantly in urinary tract than Gd(DTPA-BMA. The fast elimination kinetics is ideal for functional evaluation of the kidneys. The morphology of the kidneys and urinary tract was better visualized by the biodegradable nanoglobular contrast agent than Gd(DTPA-BMA. The agent also resulted in low liver contrast enhancement, indicating low nonspecific tissue deposition. These features render the G4 nanoglobule-cystamine-(Gd-DO3A conjugate a promising contrast agent for magnetic

  19. 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...

  20. Gd-based Contrast Enhancement of the Perivascular Spaces in the Basal Ganglia.

    Science.gov (United States)

    Naganawa, Shinji; Nakane, Toshiki; Kawai, Hisashi; Taoka, Toshiaki

    2017-01-10

    In textbooks, the perivascular space (PVS) is described as non-enhancing after the intravenous administration of gadolinium-based contrast agent (IV-GBCA). We noticed that the PVS sometimes has high signal intensity (SI) on heavily T 2 -weighted 3D-FLAIR (hT 2 -FL) images obtained 4 h after IV-GBCA. The purpose of this study was to retrospectively evaluate the contrast enhancement of the PVS. In 8 healthy subjects and 19 patients with suspected endolymphatic hydrops, magnetic resonance cisternography (MRC) and hT 2 -FL images were obtained before and 4 h after a single dose of IV-GBCA. No subjects had renal insufficiency. On axial MRC at the level of the anterior commissure (AC)-posterior commissure (PC) line, 1 cm circular regions of interest (ROIs) were drawn centering on the PVS in the bilateral basal ganglia and thalami. Three-millimeter diameter ROIs were set in the cerebrospinal fluid (CSF) of the bilateral ambient cistern. The ROIs on MRC were copied onto the hT 2 -FL images and the SI was measured. The SI ratio (SIR) was defined as SIR PVS = SI of PVS/SI of the thalami, and SIR CSF = SI of CSF/SI of the thalami. The average of the bilateral values was used for the calculation. The SIR CSF , SIR PVS , and SI of the thalami were compared between before and 4 h after IV-GBCA. The SIR was increased significantly from 1.02 ± 0.37 to 2.65 ± 0.82 in the CSF (P glymphatic system (waste clearance system) of the brain.

  1. Diagnostic usefulness of segmental and linear enhancement in dynamic breast MRI

    International Nuclear Information System (INIS)

    Morakkabati-Spitz, N.; Leutner, C.; Schild, H.; Traeber, F.; Kuhl, C.

    2005-01-01

    The aim of this study was the evaluation of the diagnostic usefulness of ductal or segmental enhancement in dynamic breast MRI. Segmental and ductal enhancement have been established as the breast MRI hallmarks of intraductal breast cancer (DCIS); however, the positive predictive value of this imaging finding is still unknown. In our study, we analysed the overall prevalence of a segmental or a linear enhancement pattern on breast MRI for an unselected cohort of patients. The aim was to evaluate the diagnostic usefulness of segmental or linear enhancement. Second, we asked whether biopsy was necessary also in the absence of mammographic findings suggestive of DCIS. Prospective, consecutive evaluation of 1,003 patients undergoing bilateral dynamic breast MRI. Studies were interpreted by two experienced breast radiologists. A diagnostic or screening two-view mammogram was available for all patients. Biopsy or short-term breast MRI follow-up was recommended for patients showing a segmental or a linear enhancement pattern on breast MRI. The patients' final diagnoses were established by imaging guided excisional or core biopsy or by clinical plus conventional imaging follow-up for a period of 2 years. The prevalence of segmental or linear enhancement was determined for patients with a final diagnosis of benign breast disease compared with those with a diagnosis of breast cancer. One hundred twenty patients had invasive breast cancer, 24 patients had DCIS and 859 patients had unsuspicious breast MRI or benign breast disease. A segmental or a linear enhancement pattern was found for 50/1,003 (5%) patients (17 DCIS, 33 benign breast diseases). Accordingly, the positive predictive value of segmental and linear enhancement is 34% (17/50); the specificity of this criterion is 96% (826/859). For 4/24 (17%) patients, DCIS was visible as segmental or linear enhancement on dynamic breast MRI, whereas no abnormalities were visible on the corresponding mammogram. The overall

  2. Enhanced MRI in lumbar disc herniation. Study on the types of herniation and histological findings

    International Nuclear Information System (INIS)

    Koh, Sadao; Okamura, Yuji; Honda, Eiichiro; Takazawa, Shunji; Ohno, Ryuichi; Yasuma, Tsuguo

    1999-01-01

    In the cases which had surgery after enhanced MRI, prolapsed form of hernia and the usefulness of enhanced MRI were examined. The patients were 13 males (14 intervertebral discs) and 5 females (6 intervertebral discs) with lumber disc herniation. The lumber disc herniation was classified into 3 types reference to Macnab's classification; SE (protrusion and subligamentous extrusion), TE (transligamentous extrusion) and SEQ (sequestration). Prolapsed forms were identified in 20 intervertebral discs. Enhanced MRI showed positive in 9 intervertebral discs (SE 1, TE 4 and SEQ 4) and showed negative in 11 discs (SE 10 and TE 1). As for the period from development to enhanced MRI, the significant difference wasn't recognized between positive group and negative group. The diagnostic rate of enhanced MRI was 88.9% (8/9) in sensitivity, 90.9% (10/11) in specificity and 90.0% (18/20) in accuracy. In enhanced MRI, engorged epidural venous plexus was also imaged, and minute change as only annular tear couldn't be detected. Looking from 2 directions crossing at right angles, the effect of contrast enhancement should be judged. (K.H.)

  3. Enhanced MRI in lumbar disc herniation. Study on the types of herniation and histological findings

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Sadao; Okamura, Yuji; Honda, Eiichiro; Takazawa, Shunji [Misato Junshin Hospital, Saitama (Japan); Ohno, Ryuichi; Yasuma, Tsuguo

    1999-06-01

    In the cases which had surgery after enhanced MRI, prolapsed form of hernia and the usefulness of enhanced MRI were examined. The patients were 13 males (14 intervertebral discs) and 5 females (6 intervertebral discs) with lumber disc herniation. The lumber disc herniation was classified into 3 types reference to Macnab's classification; SE (protrusion and subligamentous extrusion), TE (transligamentous extrusion) and SEQ (sequestration). Prolapsed forms were identified in 20 intervertebral discs. Enhanced MRI showed positive in 9 intervertebral discs (SE 1, TE 4 and SEQ 4) and showed negative in 11 discs (SE 10 and TE 1). As for the period from development to enhanced MRI, the significant difference wasn't recognized between positive group and negative group. The diagnostic rate of enhanced MRI was 88.9% (8/9) in sensitivity, 90.9% (10/11) in specificity and 90.0% (18/20) in accuracy. In enhanced MRI, engorged epidural venous plexus was also imaged, and minute change as only annular tear couldn't be detected. Looking from 2 directions crossing at right angles, the effect of contrast enhancement should be judged. (K.H.)

  4. Assessment of MRI and dynamic contrast-enhanced MRI in the differential diagnosis of adenomatoid odontogenic tumor

    International Nuclear Information System (INIS)

    Asaumi, Jun-ichi; Yanagi, Yoshinobu; Konouchi, Hironobu; Hisatomi, Miki; Matsuzaki, Hidenobu; Shigehara, Hiroshi; Kishi, Kanji

    2004-01-01

    The radiographical differentiation of adenomatoid odontogenic tumor (AOT) from dentigerous cysts, calcifying odontogenic cysts, calcifying epithelial odontogenic tumors, odontogenic keratocysts and amelobastomas is sometimes difficult. We attempted to differentiate AOT from other lesions similar to AOT in radiographic findings using MRI. The MRI features of AOT in our three cases included homogeneous low SI in the cystic portion and homogeneous intermediate SI in the solid portion on T1WI, homogeneous high SI in the cystic portion and intermediate to slightly high SI in the solid portion on T2WI and enhancement of only the solid portion on CE-T1WI although none of the sequences included SI of calcifications. The contrast index curves in the three cases of AOT showed a gradual increase to 300 s, which signified a benign tumor. These MRI features were characteristic features of AOT and might be a basis for differentiating AOT from the above possible lesions in radiographic examinations

  5. Human tumor cell proliferation evaluated using manganese-enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Rod D Braun

    Full Text Available Tumor cell proliferation can depend on calcium entry across the cell membrane. As a first step toward the development of a non-invasive test of the extent of tumor cell proliferation in vivo, we tested the hypothesis that tumor cell uptake of a calcium surrogate, Mn(2+ [measured with manganese-enhanced MRI (MEMRI], is linked to proliferation rate in vitro.Proliferation rates were determined in vitro in three different human tumor cell lines: C918 and OCM-1 human uveal melanomas and PC-3 prostate carcinoma. Cells growing at different average proliferation rates were exposed to 1 mM MnCl(2 for one hour and then thoroughly washed. MEMRI R(1 values (longitudinal relaxation rates, which have a positive linear relationship with Mn(2+ concentration, were then determined from cell pellets. Cell cycle distributions were determined using propidium iodide staining and flow cytometry. All three lines showed Mn(2+-induced increases in R(1 compared to cells not exposed to Mn(2+. C918 and PC-3 cells each showed a significant, positive correlation between MEMRI R(1 values and proliferation rate (p≤0.005, while OCM-1 cells showed no significant correlation. Preliminary, general modeling of these positive relationships suggested that pellet R(1 for the PC-3 cells, but not for the C918 cells, could be adequately described by simply accounting for changes in the distribution of the cell cycle-dependent subpopulations in the pellet.These data clearly demonstrate the tumor-cell dependent nature of the relationship between proliferation and calcium influx, and underscore the usefulness of MEMRI as a non-invasive method for investigating this link. MEMRI is applicable to study tumors in vivo, and the present results raise the possibility of evaluating proliferation parameters of some tumor types in vivo using MEMRI.

  6. Enhancement of encaged electron concentration by Sr(2+) doping and improvement of Gd(3+) emission through controlling encaged anions in conductive C12A7 phosphors.

    Science.gov (United States)

    Zhang, Meng; Liu, Yuxue; Zhu, Hancheng; Yan, Duanting; Yang, Jian; Zhang, Xinyang; Liu, Chunguang; Xu, Changshan

    2016-07-28

    Conductive C12A7:0.1%Gd(3+),y%Sr(2+) powders with different Sr(2+) doping concentrations have been prepared in a H2 atmosphere by a solid state method in combination with subsequent UV-irradiation. The encaged electron concentration could be modulated through tuning Sr(2+) doping and its maximum value reaches 2.3 × 10(19) cm(-3). This is attributed to the competition between enhanced uptake and the release of the encaged anions during their formation and diffusion processes and the suppression of encaged electrons generation due to the increased encaged OH(-) anions and the decreased encaged O(2-) anions. Although there exists encaged electrons and different encaged anions (O(2-), H(-) and OH(-)) in C12A7 conductive powders prepared through the hydrogen route, a dominant local environment around Gd(3+) could be observed using electron spin resonance (ESR) detection. It can be ascribed to the stronger coupling of the encaged OH(-) to the framework of C12A7 than those of the encaged electrons, O(2-) and H(-) anions. In addition, emission of Gd(3+) ions is enhanced under UV or low voltage electron beam excitation and a new local environment around Gd(3+) ions appears through the thermal annealing in air because of the decrease of the encaged OH(-) anions and the increase of the encaged O(2-) anions. Our results suggested that Sr(2+) doping in combination with thermal annealing in air is an effective strategy for increasing the conductive performance and enhancing the emission of rare earth ions doped into C12A7 conductive phosphors for low-voltage field emission displays (FEDs).

  7. Value of contrast-enhanced MRI of breast after silicone implant

    International Nuclear Information System (INIS)

    Heinig, A.; Heywang-Koebrunner, S.H.; Viehweg, P.; Spielmann, R.P.; Lampe, D.; Buchmann, J.

    1997-01-01

    Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing granulomas specificity could not be improved. Contrast-enhanded MRI allowed decisive additional information in our study group and improved the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI allowed decisive additional information in our study group and improved the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI is recommended in patients with diagnostic problems or high risk of recurrence after silicone implants. (orig.) [de

  8. Ex vivo assessment of polyol coated-iron oxide nanoparticles for MRI diagnosis applications: toxicological and MRI contrast enhancement effects

    Science.gov (United States)

    Bomati-Miguel, Oscar; Miguel-Sancho, Nuria; Abasolo, Ibane; Candiota, Ana Paula; Roca, Alejandro G.; Acosta, Milena; Schwartz, Simó; Arus, Carles; Marquina, Clara; Martinez, Gema; Santamaria, Jesus

    2014-03-01

    Polyol synthesis is a promising method to obtain directly pharmaceutical grade colloidal dispersion of superparamagnetic iron oxide nanoparticles (SPIONs). Here, we study the biocompatibility and performance as T2-MRI contrast agents (CAs) of high quality magnetic colloidal dispersions (average hydrodynamic aggregate diameter of 16-27 nm) consisting of polyol-synthesized SPIONs (5 nm in mean particle size) coated with triethylene glycol (TEG) chains (TEG-SPIONs), which were subsequently functionalized to carboxyl-terminated meso-2-3-dimercaptosuccinic acid (DMSA) coated-iron oxide nanoparticles (DMSA-SPIONs). Standard MTT assays on HeLa, U87MG, and HepG2 cells revealed that colloidal dispersions of TEG-coated iron oxide nanoparticles did not induce any loss of cell viability after 3 days incubation with dose concentrations below 50 μg Fe/ml. However, after these nanoparticles were functionalized with DMSA molecules, an increase on their cytotoxicity was observed, so that particles bearing free terminal carboxyl groups on their surface were not cytotoxic only at low concentrations (MRI studies in mice indicated that both types of coated-iron oxide nanoparticles produced higher negative T2-MRI contrast enhancement than that measured for a similar commercial T2-MRI CAs consisting in dextran-coated ultra-small iron oxide nanoparticles (Ferumoxtran-10). In conclusion, the above attributes make both types of as synthesized coated-iron oxide nanoparticles, but especially DMSA-SPIONs, promising candidates as T2-MRI CAs for nanoparticle-enhanced MRI diagnosis applications.

  9. Dural invasion of meningiomas adjacent to the tumor margin on Gd-DTPA-enhanced MR images: histopathologic correlation

    International Nuclear Information System (INIS)

    Hutzelmann, A.; Palmie, S.; Freund, M.; Heller, M.; Buhl, R.

    1998-01-01

    In intracranial meningiomas a flat, contrast-enhancing, dural structure adjacent to the tumor can occasionally be observed on gadolinium-DTPA-enhanced MR images. We wished to evaluate whether there is a correlation between MR images and meningeal invasion of intracranial meningiomas. The study included 54 patients with intracranial meningioma and the meningeal sign. MR studies included T2-weighted and gadolinium-DTPA-enhanced T1-weighted images in axial, coronal, and sagittal planes. Histopathologic examinations were done on the meningiomas adjacent to the dura mater. The meningeal sign on MRI was observed from 2 up to 35 mm from the main tumor mass in 31 (57 %) of the 54 patients. In 20 of these 31 the histopathologic examination showed tumor invasion, while 11 patients had no tumor invasion but tissue proliferation, hypervascularity, and vascular dilatation. Seven of the 23 meningiomas without the meningeal sign had histologically proven infiltration of the adjacent dura. MR imaging is not able to determine definitive whether or not there is dural infiltration of the meningiomas. In conclusion, resection of the tumor with a wide margin is necessary to achieve complete excision of meningioma and to avoid recurrence. (orig.)

  10. Diagnostic value of dynamic contrast-enhanced MRI for submucosal palatal tumors

    International Nuclear Information System (INIS)

    Matsuzaki, Hidenobu; Yanagi, Yoshinobu; Hara, Marina; Katase, Naoki; Hisatomi, Miki; Unetsubo, Teruhisa; Konouchi, Hironobu; Takenobu, Toshihiko

    2012-01-01

    Objectives: To evaluate the diagnostic value of dynamic contrast-enhanced MRI (DCE-MRI) for differentiating between benign and malignant tumors in the palate. Materials and methods: 26 patients with submucosal palatal tumors were preoperatively examined using DCE-MRI. Their maximum contrast index (CImax), time of CImax (Tmax), and washout ratios (WR300 and WR600) were determined from contrast index curves. The submucosal palatal tumors were divided into two groups according to their Tmax values: the early enhancement group (Tmax 2 = 0.92, P < 0.001). Conclusions: Tmax is a useful parameter for distinguishing between benign and malignant submucosal palatal tumors.

  11. Enhanced and uniform in-field performance in long (Gd, Y)-Ba-Cu-O tapes with zirconium doping fabricated by metal-organic chemical vapor deposition

    International Nuclear Information System (INIS)

    Selvamanickam, V; Guevara, A; Zhang, Y; Kesgin, I; Xie, Y; Carota, G; Chen, Y; Dackow, J; Zhang, Y; Zuev, Y; Cantoni, C; Goyal, A; Coulter, J; Civale, L

    2010-01-01

    The influence of Zr doping in (Gd, Y)-Ba-Cu-O ((Gd, Y)BCO) tapes made by metal-organic chemical vapor deposition has been studied with a specific objective of uniform and reproducible enhancement in in-field critical current (I c ) over long lengths. 50 m long tapes with 7.5 and 10 at.% Zr doping in 1 μm thick (Gd, Y)BCO films have been found to exhibit a sharply enhanced peak in I c in the orientation of field parallel to the c-axis and retain 28% of their self-field I c value at 77 K and 1 T. BaZrO 3 (BZO) nanocolumn density in the cross-sectional microstructure was found to increase with increasing Zr addition. The end segments of the 50 m long tapes were found to display nearly identical angular dependence of critical current at 77 K and 1 T, indicative of the uniformity in in-field performance over this length. A 610 m long tape was fabricated with 10% Zr doping and a 130 m segment showed a 3.2% uniformity in critical current measured every meter in the orientation of B || c-axis. A retention factor of 36% of the zero-field I c value measured at 0.52 T over the 130 m is consistent with that obtained in short samples.

  12. Enhanced and uniform in-field performance in long (Gd, Y)-Ba-Cu-O tapes with zirconium doping fabricated by metal-organic chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Selvamanickam, V; Guevara, A; Zhang, Y; Kesgin, I [Texas Center for Superconductivity and Department of Mechanical Engineering, University of Houston, Houston, TX 77059 (United States); Xie, Y; Carota, G; Chen, Y; Dackow, J [SuperPower Incorporated, 450 Duane Avenue Schenectady, NY 12304 (United States); Zhang, Y; Zuev, Y; Cantoni, C; Goyal, A [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Coulter, J; Civale, L [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2010-01-15

    The influence of Zr doping in (Gd, Y)-Ba-Cu-O ((Gd, Y)BCO) tapes made by metal-organic chemical vapor deposition has been studied with a specific objective of uniform and reproducible enhancement in in-field critical current (I{sub c}) over long lengths. 50 m long tapes with 7.5 and 10 at.% Zr doping in 1 {mu}m thick (Gd, Y)BCO films have been found to exhibit a sharply enhanced peak in I{sub c} in the orientation of field parallel to the c-axis and retain 28% of their self-field I{sub c} value at 77 K and 1 T. BaZrO{sub 3} (BZO) nanocolumn density in the cross-sectional microstructure was found to increase with increasing Zr addition. The end segments of the 50 m long tapes were found to display nearly identical angular dependence of critical current at 77 K and 1 T, indicative of the uniformity in in-field performance over this length. A 610 m long tape was fabricated with 10% Zr doping and a 130 m segment showed a 3.2% uniformity in critical current measured every meter in the orientation of B || c-axis. A retention factor of 36% of the zero-field I{sub c} value measured at 0.52 T over the 130 m is consistent with that obtained in short samples.

  13. Enhanced and Uniform in-Field Performance in Long (Gd,Y)-Ba-Cu-O Tapes with Zirconium Doping Fabricated by Metal Organic Chemical Vapor Deposition

    Energy Technology Data Exchange (ETDEWEB)

    Selvamanickam, V. [SuperPower Incorporated, Schenectady, New York; Guevara, A. [University of Houston, Houston; Zhang, Y. [University of Houston, Houston; Kesign, I. [University of Houston, Houston; Xie, Y. Y. [SuperPower Incorporated, Schenectady, New York; Carota, G. [SuperPower Incorporated, Schenectady, New York; Chen, Y. [SuperPower Incorporated, Schenectady, New York; Dackow, J. [SuperPower Incorporated, Schenectady, New York; Zhang, Yifei [ORNL; Zuev, Yuri L [ORNL; Cantoni, Claudia [ORNL; Goyal, Amit [ORNL; Coulter, J. [Los Alamos National Laboratory (LANL); Civale, L. [Los Alamos National Laboratory (LANL)

    2010-01-01

    The influence of Zr doping in (Gd, Y)-Ba-Cu-O ((Gd, Y)BCO) tapes made by metal-organic chemical vapor deposition has been studied with a specific objective of uniform and reproducible enhancement in in-field critical current (I{sub c}) over long lengths. 50 m long tapes with 7.5 and 10 at.% Zr doping in 1 {mu}m thick (Gd, Y)BCO films have been found to exhibit a sharply enhanced peak in I{sub c} in the orientation of field parallel to the c-axis and retain 28% of their self-field I{sub c} value at 77 K and 1 T. BaZrO{sub 3} (BZO) nanocolumn density in the cross-sectional microstructure was found to increase with increasing Zr addition. The end segments of the 50 m long tapes were found to display nearly identical angular dependence of critical current at 77 K and 1 T, indicative of the uniformity in in-field performance over this length. A 610 m long tape was fabricated with 10% Zr doping and a 130 m segment showed a 3.2% uniformity in critical current measured every meter in the orientation of {beta} {parallel} c-axis. A retention factor of 36% of the zero-field I{sub c} value measured at 0.52 T over the 130 m is consistent with that obtained in short samples.

  14. 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.

  15. Enhanced reducibility and electronic conductivity of Nb or W doped Ce0.9Gd0.1O1.95 - δ

    DEFF Research Database (Denmark)

    Chatzichristodoulou, Christodoulos; Ricote, Sandrine; Foghmoes, Søren Preben Vagn

    2015-01-01

    The transport and thermomechanical properties of acceptor (Gd) and donor (Nb or W) co-doped ceria were investigated. The solubility limit of Nb in Ce0.9Gd0.1O2 - δ (CGO10) exceeds 4 at.%, whereas that of W is approximately 2 at.%. Both the thermal and stoichiometric expansion coefficients...... are decreased relative to that of CGO10. Charge compensation of the donor dopants takes place primarily by annihilation of oxide ion vacancies, and a sharp decrease in ionic mobility is observed upon Nb or W doping of CGO10. On the other hand, the n-type electronic conductivity, associated with the reduction...... of Ce4+, increases upon doping with Nb or W, due to enhanced reducibility of cerium. This is beneficial for applications where electronic conductivity is also required, like oxygen permeation membranes. Modeling shows that 4 at.% Nb or W doped CGO10 will deliver higher oxygen fluxes than CGO10, due...

  16. Gadolinium-DOTA enhanced MRI of painful osseous crises in children with sickle cell anemia

    International Nuclear Information System (INIS)

    Bonnerot, V.; Sebag, G.; Montalembert, M. de; Wioland, M.; Glorion, C.; Girot, R.; Lallemand, D.

    1994-01-01

    In order to evaluate the role of gadolinium-DOTA enhanced MRI in the management of painful osseous crises in children with sickle cell anemia (SCA), nine children with SCA underwent MRI, bone scans and ultrasonographic studies during 11 osseous crises. Imaging findings were compared with the final diagnosis: three acute osteomyelitis (AO) and 16 acute infarcts (AI). MRI could not differentiate AO from AI. The appearance of severe AI was very misleading and was similar to the usual appearance of AO, including soft tissue changes, periosteal reaction and patterns of enhancement. Gadolinium-DOTA enhanced MRI was useful for determining the anatomic site and extent of AO or AI and for distinguishing between necrotic material, fluid collection and vascularized inflammatory tissue. It can also help to guide the aspiration of intraosseous, subperiosteal and soft tissue fluid collections. (orig.)

  17. Contrast-enhanced MRI features in the early diagnosis of Juvenile Idiopathic Arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Hemke, Robert; Maas, Mario [University of Amsterdam, Department of Radiology Academic Medical Center, Amsterdam (Netherlands); Kuijpers, Taco W.; Schonenberg-Meinema, Dieneke [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Nusman, Charlotte M. [University of Amsterdam, Department of Radiology Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Rossum, Marion A.J. van; Berg, J.M. van den [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Department of Pediatric Rheumatology, Reade, Amsterdam (Netherlands); Dolman, Koert M. [Department of Pediatric Rheumatology, Reade, Amsterdam (Netherlands); St. Lucas Andreas Hospital, Department of Pediatrics, Amsterdam (Netherlands)

    2015-11-15

    To determine whether clinical, laboratory or Magnetic Resonance Imaging (MRI) measures differentiate Juvenile Idiopathic Arthritis (JIA) from other forms of active childhood arthritis. We prospectively collected data of 80 treatment-naive patients clinically suspected of JIA with active non-infectious arthritis of (at least) one knee for <12 months duration. Upon presentation patients underwent clinical and laboratory assessments and contrast-enhanced MRI. MRI was not used as a diagnostic criterion. Forty-four (55 %) patients were clinically diagnosed with JIA, whereas in 36 (45 %) patients the diagnosis of JIA was discarded on clinical or laboratory findings. MRI-based synovitis was present in 27 (61.4 %) JIA patients and in 7 (19.4 %) non-JIA patients (P < 0.001). Five factors (male gender, physician's global assessment of overall disease activity, joints with limited range of motion, HLA-B27, MRI-based synovitis) were associated with the onset of JIA. In multivariate analysis MRI-based synovitis proved to be independently associated with JIA (OR 6.58, 95 % CI 2.36-18.33). In patients with MRI-based synovitis, the RR of having JIA was 3.16 (95 % CI 1.6-6.4). The presence of MRI-based synovitis is associated with the clinical onset of JIA. Physical examination could be supported by MRI, particularly to contribute in the early differentiation of different forms of non-infectious childhood arthritis. (orig.)

  18. Contrast-enhanced MRI features in the early diagnosis of Juvenile Idiopathic Arthritis

    International Nuclear Information System (INIS)

    Hemke, Robert; Maas, Mario; Kuijpers, Taco W.; Schonenberg-Meinema, Dieneke; Nusman, Charlotte M.; Rossum, Marion A.J. van; Berg, J.M. van den; Dolman, Koert M.

    2015-01-01

    To determine whether clinical, laboratory or Magnetic Resonance Imaging (MRI) measures differentiate Juvenile Idiopathic Arthritis (JIA) from other forms of active childhood arthritis. We prospectively collected data of 80 treatment-naive patients clinically suspected of JIA with active non-infectious arthritis of (at least) one knee for <12 months duration. Upon presentation patients underwent clinical and laboratory assessments and contrast-enhanced MRI. MRI was not used as a diagnostic criterion. Forty-four (55 %) patients were clinically diagnosed with JIA, whereas in 36 (45 %) patients the diagnosis of JIA was discarded on clinical or laboratory findings. MRI-based synovitis was present in 27 (61.4 %) JIA patients and in 7 (19.4 %) non-JIA patients (P < 0.001). Five factors (male gender, physician's global assessment of overall disease activity, joints with limited range of motion, HLA-B27, MRI-based synovitis) were associated with the onset of JIA. In multivariate analysis MRI-based synovitis proved to be independently associated with JIA (OR 6.58, 95 % CI 2.36-18.33). In patients with MRI-based synovitis, the RR of having JIA was 3.16 (95 % CI 1.6-6.4). The presence of MRI-based synovitis is associated with the clinical onset of JIA. Physical examination could be supported by MRI, particularly to contribute in the early differentiation of different forms of non-infectious childhood arthritis. (orig.)

  19. Cardiovascular MRI with ferumoxytol

    International Nuclear Information System (INIS)

    Finn, J.P.; Nguyen, K.-L.; Han, F.; Zhou, Z.; Salusky, I.; Ayad, I.; Hu, P.

    2016-01-01

    The practice of contrast-enhanced magnetic resonance angiography (CEMRA) has changed significantly in the span of a decade. Concerns regarding gadolinium (Gd)-associated nephrogenic systemic fibrosis in those with severely impaired renal function spurred developments in low-dose CEMRA and non-contrast MRA as well as efforts to seek alternative MR contrast agents. Originally developed for MR imaging use, ferumoxytol (an ultra-small superparamagnetic iron oxide nanoparticle), is currently approved by the US Food and Drug Administration for the treatment of iron deficiency anaemia in adults with renal disease. Since its clinical availability in 2009, there has been rising interest in the scientific and clinical use of ferumoxytol as an MR contrast agent. The unique physicochemical and pharmacokinetic properties of ferumoxytol, including its long intravascular half-life and high r 1 relaxivity, support a spectrum of MRI applications beyond the scope of Gd-based contrast agents. Moreover, whereas Gd is not found in biological systems, iron is essential for normal metabolism, and nutritional iron deficiency poses major public health challenges worldwide. Once the carbohydrate shell of ferumoxytol is degraded, the elemental iron at its core is incorporated into the reticuloendothelial system. These considerations position ferumoxytol as a potential game changer in the field of CEMRA and MRI. In this paper, we aim to summarise our experience with the cardiovascular applications of ferumoxytol and provide a brief synopsis of ongoing investigations on ferumoxytol-enhanced MR applications.

  20. Quantitative Molecular Imaging with a Single Gd-Based Contrast Agent Reveals Specific Tumor Binding and Retention in Vivo.

    Science.gov (United States)

    Johansen, Mette L; Gao, Ying; Hutnick, Melanie A; Craig, Sonya E L; Pokorski, Jonathan K; Flask, Chris A; Brady-Kalnay, Susann M

    2017-06-06

    Magnetic resonance imaging (MRI) has become an indispensable tool in the diagnosis and treatment of many diseases, especially cancer. However, the poor sensitivity of MRI relative to other imaging modalities, such as PET, has hindered the development and clinical use of molecular MRI contrast agents that could provide vital diagnostic information by specifically locating a molecular target altered in the disease process. This work describes the specific and sustained in vivo binding and retention of a protein tyrosine phosphatase mu (PTPμ)-targeted, molecular magnetic resonance (MR) contrast agent with a single gadolinium (Gd) chelate using a quantitative MRI T 1 mapping technique in glioma xenografts. Quantitative T 1 mapping is an imaging method used to measure the longitudinal relaxation time, the T 1 relaxation time, of protons in a magnetic field after excitation by a radiofrequency pulse. T 1 relaxation times can in turn be used to calculate the concentration of a gadolinium-containing contrast agent in a region of interest, thereby allowing the retention or clearance of an agent to be quantified. In this context, retention is a measure of molecular contrast agent binding. Using conventional peptide chemistry, a PTPμ-targeted peptide was linked to a chelator that had been conjugated to a lysine residue. Following complexation with Gd, this PTPμ-targeted molecular contrast agent containing a single Gd ion showed significant tumor enhancement and a sustained increase in Gd concentration in both heterotopic and orthotopic tumors using dynamic quantitative MRI. This single Gd-containing PTPμ agent was more effective than our previous version with three Gd ions. Differences between nonspecific and specific agents, due to specific tumor binding, can be determined within the first 30 min after agent administration by examining clearance rates. This more facile chemistry, when combined with quantitative MR techniques, allows for widespread adoption by academic

  1. Magnetic and transport properties of sputtered Gd-Y multilayers

    International Nuclear Information System (INIS)

    Freitas, P.P.; From, M.; Melo, L.V.

    1991-01-01

    Gd-Y-Gd multilayers were prepared that show a magnetoresistance enhancement for an Y layer separation of 30 A. This magnetoresistance enhancement is an interface effect and occurs in samples where some degree of antiferromagnetic coupling is present

  2. Three-dimensional evaluation of lumbar disc hernia and prediction of absorption by enhanced MRI

    International Nuclear Information System (INIS)

    Kawaji, Youichi; Uchiyama, Seiji; Yagi, Eiichi

    2001-01-01

    Both the spontaneous shrinkage and the disappearance of disc hernia have been confirmed through the use of computed tomography (CT) and magnetic resonance imaging (MRI). There is, however, no practical method to predict the likely absorption of the herniated mass. The objective of this study was to predict the spontaneous absorption of disc hernia by MRI, and to select the optimum treatment. The study involved 65 patients with lumbar disc hernias. Conservative treatment was carried out in 21 patients, while 44 patients underwent herniotomy. In the nonoperated patients, an MRI was taken both during the painful period, and shortly after pain remission. Hernial shrinkage was evaluated according to the decrease in the calculated volume, in addition to the decrease in hernial area, calculated by MRI. In the operated group, preoperative MRI enhancement, type of hernia, and invasion of granulation tissue in the histological specimens were studied. In the 21 nonoperated patients, the volume (mean ±SD) was 0.488±208 cm 3 (range, 0.197-0.931 cm 3 ) in the painful period and 0.214±0.181 cm 3 (range, 0.0-0.744 cm 3 ) in the remission period. This decrease in volume was statistically significant. There was also a greater decrease in hernias exhibiting positive enhancement by MRI. In the operated patients, hernias that penetrated the posterior longitudinal ligament (PLL) had high rates of preoperative enhancement, and these hernias showed invasion of granulation tissue with marked neovascularization. Positive enhancement by MRI confirms an ongoing absorption process. Enhanced MRI can be a good method for the prediction of spontaneous absorption of lumbar disc hernias. (author)

  3. Three-dimensional evaluation of lumbar disc hernia and prediction of absorption by enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kawaji, Youichi; Uchiyama, Seiji [Niigata Univ. (Japan). School of Medicine; Yagi, Eiichi

    2001-07-01

    Both the spontaneous shrinkage and the disappearance of disc hernia have been confirmed through the use of computed tomography (CT) and magnetic resonance imaging (MRI). There is, however, no practical method to predict the likely absorption of the herniated mass. The objective of this study was to predict the spontaneous absorption of disc hernia by MRI, and to select the optimum treatment. The study involved 65 patients with lumbar disc hernias. Conservative treatment was carried out in 21 patients, while 44 patients underwent herniotomy. In the nonoperated patients, an MRI was taken both during the painful period, and shortly after pain remission. Hernial shrinkage was evaluated according to the decrease in the calculated volume, in addition to the decrease in hernial area, calculated by MRI. In the operated group, preoperative MRI enhancement, type of hernia, and invasion of granulation tissue in the histological specimens were studied. In the 21 nonoperated patients, the volume (mean {+-}SD) was 0.488{+-}208 cm{sup 3} (range, 0.197-0.931 cm{sup 3}) in the painful period and 0.214{+-}0.181 cm{sup 3} (range, 0.0-0.744 cm{sup 3}) in the remission period. This decrease in volume was statistically significant. There was also a greater decrease in hernias exhibiting positive enhancement by MRI. In the operated patients, hernias that penetrated the posterior longitudinal ligament (PLL) had high rates of preoperative enhancement, and these hernias showed invasion of granulation tissue with marked neovascularization. Positive enhancement by MRI confirms an ongoing absorption process. Enhanced MRI can be a good method for the prediction of spontaneous absorption of lumbar disc hernias. (author)

  4. Enhancement pattern of small hepatic hemangioma: findings on multiphase spiral CT and dynamic MRI

    International Nuclear Information System (INIS)

    Choi, Byung In; Lee, Seung Koo; Kim, Myeong Jin; Chung, Jae Joon; Yoo, Hyung Sik; Lee, Jong Tae

    1999-01-01

    To compare the enhancement characteristics of small hemangiomas seen on multiphase spiral CT and dynamic MR imaging. Thirteen patients with 20 hepatic hemangiomas less than 25mm in diameter underwent both multiphase spiral CT and dynamic MR imaging. All lesions were assigned to one of three classified into 3 categories according to the enhancement pattern seen on multiphase spiral CT : typical delayed pooling, atypical early enhancement, or continuous low attenuation. The enhancement patterns seen on spiral CT and on dynamic MRI were correlated. On CT scans, ten lesions (50%) showed delayed pooling. Six (30%) showed early arterial enhancement and four (20%) showed continuous low attenuation. On delayed-phase MRI, all lesions showed delayed high signal intensity compared to adjacent liver parenchyma. Four of six lesions with early enhancement on CT showed peripheral globular enhancement on early arterial-phase MRI. On multiphase spiral CT scans, small hemangiomas can show variable atypical enhancement features. In this situation, contrast-enhanced dynamic MRI is helpful for the diagnosis of hemangiomas

  5. Gd-EOB-DTPA-Enhanced MR Imaging of the Liver: The Effect on T2 Relaxation Times and Apparent Diffusion Coefficient (ADC)

    International Nuclear Information System (INIS)

    Cieszanowski, Andrzej; Podgórska, Joanna; Rosiak, Grzegorz; Maj, Edyta; Grudziński, Ireneusz P.; Kaczyński, Bartosz; Szeszkowski, Wojciech; Milczarek, Krzysztof; Rowiński, Olgierd

    2016-01-01

    To investigate the effect of gadoxetic acid disodium (Gd-EOB-DTPA) on T2 relaxation times and apparent diffusion coefficient (ADC) values of the liver and focal liver lesions on a 1.5-T system. Magnetic resonance (MR) studies of 50 patients with 35 liver lesions were retrospectively analyzed. All examinations were performed at 1.5T and included T2-weighted turbo spin-echo (TSE) and diffusion-weighted (DW) images acquired before and after intravenous administration of Gd-EOB-DTPA. To assess the effect of this hepatobiliary contrast agent on T2-weighted TSE images and DW images T2 relaxation times and ADC values of the liver and FLLs were calculated and compared pre- and post-injection. The mean T2 relaxation times of the liver and focal hepatic lesions were lower on enhanced than on unenhanced T2-weighted TSE images (decrease of 2.7% and 3.6% respectively), although these differences were not statistically significant. The mean ADC values of the liver showed statistically significant decrease (of 4.6%) on contrast-enhanced DW images, compared to unenhanced images (P>0.05). The mean ADC value of liver lesions was lower on enhanced than on unenhanced DW images, but this difference (of 2.9%) did not reach statistical significance. The mean T2 relaxation times of the liver and focal liver lesions as well as the mean ADC values of liver lesions were not significantly different before and after administration of Gd-EOB-DTPA. Therefore, acquisition of T2-weighted and DW images between the dynamic contrast-enhanced examination and hepatobiliary phase is feasible and time-saving

  6. Gadolinium-enhanced MR angiography (Gd-MRA) of thoracic vasculature in an animal model using double-dose gadolinium and quiet breathing

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, R.J.; Strouse, P.J. [Section of Pediatric Radiology, University of Michigan Health System, Ann Arbor (United States); Londy, F.J. [Dept. of Radiology, University of Michigan Hospitals, Ann Arbor, MI (United States); Wakefield, T.W. [Dept. of Surgery, Section of Vascular Surgery, University of Michigan Hospitals, Ann Arbor, MI (United States)

    2001-08-01

    Objective. To evaluate a gadolinium-enhanced MR angiography (Gd-MRA) imaging protocol for the assessment of thoracic vessels using double-dose gadolinium and quiet breathing. An animal model was used to simulate imaging in infants and young children. Material and methods. Six baboons (Papio anubis), mean weight 5.7 kg, were sedated and intubated. After the injection of double-dose Gd-DTPA (0.2 mmol/kg) through a peripheral vein, a coronal spoiled 3D gradient-echo volume acquisition was obtained during quiet breathing. Two radiologists reviewed the images for visualization of aortic arch, brachiocephalic vessel origins, pulmonary arteries (central, upper lobe and descending branches), and pulmonary veins (upper and lower). Results. Visualization was excellent for the aortic arch, brachiocephalic vessel origins, and pulmonary arteries, including the hilar branches. Visualization was excellent for the lower and right upper pulmonary veins and fair for the left upper pulmonary vein. There was excellent agreement between radiologists. Conclusion. Imaging of thoracic vessels with Gd-MRA using double gadolinium during quiet breathing was effective in our animal model. The advantages of this technique include a short imaging time and depiction of vascular segments - branches of pulmonary arteries and intraparenchymal segments of pulmonary veins - not optimally visualized with other non-invasive imaging techniques. (orig.)

  7. Gadolinium-enhanced MR angiography (Gd-MRA) of thoracic vasculature in an animal model using double-dose gadolinium and quiet breathing

    International Nuclear Information System (INIS)

    Hernandez, R.J.; Strouse, P.J.; Londy, F.J.; Wakefield, T.W.

    2001-01-01

    Objective. To evaluate a gadolinium-enhanced MR angiography (Gd-MRA) imaging protocol for the assessment of thoracic vessels using double-dose gadolinium and quiet breathing. An animal model was used to simulate imaging in infants and young children. Material and methods. Six baboons (Papio anubis), mean weight 5.7 kg, were sedated and intubated. After the injection of double-dose Gd-DTPA (0.2 mmol/kg) through a peripheral vein, a coronal spoiled 3D gradient-echo volume acquisition was obtained during quiet breathing. Two radiologists reviewed the images for visualization of aortic arch, brachiocephalic vessel origins, pulmonary arteries (central, upper lobe and descending branches), and pulmonary veins (upper and lower). Results. Visualization was excellent for the aortic arch, brachiocephalic vessel origins, and pulmonary arteries, including the hilar branches. Visualization was excellent for the lower and right upper pulmonary veins and fair for the left upper pulmonary vein. There was excellent agreement between radiologists. Conclusion. Imaging of thoracic vessels with Gd-MRA using double gadolinium during quiet breathing was effective in our animal model. The advantages of this technique include a short imaging time and depiction of vascular segments - branches of pulmonary arteries and intraparenchymal segments of pulmonary veins - not optimally visualized with other non-invasive imaging techniques. (orig.)

  8. Postoperative enhancement on breast MRI: Time course and pattern of changes.

    Science.gov (United States)

    Mahoney, Mary C; Sharda, Radhika G

    2018-04-23

    Expected postoperative enhancement on breast MRI can appear similar to enhancement seen in recurrent or residual malignancy. Our aim was to assess the time course and patterns of enhancement at the surgical site, thereby helping to distinguish between benign and malignant postoperative enhancement. In 200 MRI scans performed in 153 patients after breast conservation treatment, 43 after surgical excision of atypia, and 4 patients after benign excisional biopsy were categorized by postoperative time interval. We defined 4 patterns of morphologic enhancement on MRI: cavity wall/seroma (Pattern I); thin linear (Pattern II); mass (Pattern III); and fat necrosis (Pattern IV). Of 200 MRI scans, 66 (33%) demonstrated enhancement at the surgical site. Enhancement typically decreased through the postoperative follow-up period. Enhancement was observed in 41% (28/68) of cases beyond the 18-month interval but was uncommon after 5 years. Pattern III enhancement was the morphologic pattern seen most commonly with malignancy (5/19 cases, 26%). When associated with delayed washout kinetics, it was even more strongly predictive of malignancy (4/5 cases, 80%). In patients with a history of excisional biopsy and no prior radiation treatment, the percentage of MRI scans showing enhancement was significantly lower than (21% vs 49% with P-value .0027) in patients who had undergone radiation. Enhancement at the surgical site occurred in one-third of cases up to 5 years after surgery, particularly in patients who underwent both radiation and surgery. Mass enhancement, particularly in conjunction with delayed washout kinetics, is most predictive of malignancy and should prompt biopsy or re-excision. © 2018 Wiley Periodicals, Inc.

  9. The utility of gadoteric acid in contrast-enhanced MRI: a review

    Directory of Open Access Journals (Sweden)

    Tartaro A

    2015-02-01

    Full Text Available Armando Tartaro, Marica Tina Maccarone Department of Neuroscience, Imaging and Clinical Sciences, and Institute for Advanced Biomedical Technologies (ITAB, “G d’Annunzio” University, Chieti-Pescara, Italy Abstract: Gadoteric acid (Dotarem® is a macrocyclic, paramagnetic, gadolinium-based contrast agent. It is used in the magnetic resonance imaging (MRI of the brain, spine, and associated tissues. Particularly, it is able to detect and visualize areas with disruption of the blood–brain barrier and/or abnormal vascularity. Gadoteric acid has been also approved for MR angiography of supraaortic vessels, cardiac MR (to detect myocardial infarctions, as well as whole-body MRI including abdominal, renal, pelvic, breast, and osteoarticular diseases. Cyclic chelates are more stable compared to linear chelates, and ionic chelates are more stable compared to nonionic chelates. Linear chelates have a greater likelihood of releasing free Gd3+ compared to cyclic chelates. Non-ionic chelates are more likely, compared to ionic chelates, to release Gd3+ from their chelates. Gadoteric acid is a cyclic ionic chelate and has the greatest kinetic stability among gadolinium-based contrast agents. In patients with chronic reduced kidney function, the use of gadolinium-based contrast agents leads to acute kidney injury and dialysis. The risk of acute kidney injury may increase with increasing dose of the contrast agents. Therefore, it is recommended to administer the lowest dose necessary for adequate imaging. The dose reduction allows protection the patients form potential risk of nephrogenic systemic fibrosis, a systemic reaction that is probably due to unbound Gd3+ ions deposited in body tissues. The dose of gadoteric acid should not exceed 0.1 mmol/kg body weight. More than one dose should not be used during a scan. Because of the lack of information on repeated administration, Dotarem® injections should not be repeated unless the interval between

  10. Is there an added value of T1-weighted contrast-enhanced fat-suppressed spin-echo MR sequences compared to STIR sequences in MRI of the foot and ankle?

    International Nuclear Information System (INIS)

    Zubler, Veronika; Zanetti, Marco; Dietrich, Tobias J.; Pfirrmann, Christian W.; Mamisch-Saupe, Nadja; Espinosa, Norman

    2017-01-01

    To prospectively compare T1-weighted fat-suppressed spin-echo magnetic resonance (MR) sequences after gadolinium application (T1wGdFS) to STIR sequences in patients with acute and chronic foot pain. In 51 patients referred for MRI of the foot and ankle, additional transverse and sagittal T1wGdFS sequences were obtained. Two sets of MR images (standard protocol with STIR or T1wGdFS) were analysed. Diagnosis, diagnostic confidence, and localization of the abnormality were noted. Standard of reference was established by an expert panel of two experienced MSK radiologists and one experienced foot surgeon based on MR images, clinical charts and surgical reports. Patients reported prospectively localization of pain. Descriptive statistics, McNemar test and Kappa test were used. Diagnostic accuracy with STIR protocol was 80% for reader 1, 67% for reader 2, with contrast-protocol 84%, both readers. Significance was found for reader 2. Diagnostic confidence for reader 1 was 1.7 with STIR, 1.3 with contrast-protocol; reader 2: 2.1/1.7. Significance was found for reader 1. Pain location correlated with STIR sequences in 64% and 52%, with gadolinium sequences in 70% and 71%. T1-weighted contrast material-enhanced fat-suppressed spin-echo magnetic resonance sequences improve diagnostic accuracy, diagnostic confidence and correlation of MR abnormalities with pain location in MRI of the foot and ankle. However, the additional value is small. (orig.)

  11. Is there an added value of T1-weighted contrast-enhanced fat-suppressed spin-echo MR sequences compared to STIR sequences in MRI of the foot and ankle?

    Energy Technology Data Exchange (ETDEWEB)

    Zubler, Veronika; Zanetti, Marco; Dietrich, Tobias J.; Pfirrmann, Christian W.; Mamisch-Saupe, Nadja [University of Zurich, Faculty of Medicine, Zurich (Switzerland); Orthopedic University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); Espinosa, Norman [University of Zurich, Faculty of Medicine, Zurich (Switzerland); Orthopedic University Hospital Balgrist, Orthopedic Surgery, Zurich (Switzerland)

    2017-08-15

    To prospectively compare T1-weighted fat-suppressed spin-echo magnetic resonance (MR) sequences after gadolinium application (T1wGdFS) to STIR sequences in patients with acute and chronic foot pain. In 51 patients referred for MRI of the foot and ankle, additional transverse and sagittal T1wGdFS sequences were obtained. Two sets of MR images (standard protocol with STIR or T1wGdFS) were analysed. Diagnosis, diagnostic confidence, and localization of the abnormality were noted. Standard of reference was established by an expert panel of two experienced MSK radiologists and one experienced foot surgeon based on MR images, clinical charts and surgical reports. Patients reported prospectively localization of pain. Descriptive statistics, McNemar test and Kappa test were used. Diagnostic accuracy with STIR protocol was 80% for reader 1, 67% for reader 2, with contrast-protocol 84%, both readers. Significance was found for reader 2. Diagnostic confidence for reader 1 was 1.7 with STIR, 1.3 with contrast-protocol; reader 2: 2.1/1.7. Significance was found for reader 1. Pain location correlated with STIR sequences in 64% and 52%, with gadolinium sequences in 70% and 71%. T1-weighted contrast material-enhanced fat-suppressed spin-echo magnetic resonance sequences improve diagnostic accuracy, diagnostic confidence and correlation of MR abnormalities with pain location in MRI of the foot and ankle. However, the additional value is small. (orig.)

  12. Selection of optimal pulse sequences for conventional and dynamic MR imaging with Gd-DTPA; A fundamental study

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Miho; Kita, Keisuke; Maeda, Masayuki (Wakayama Medical Coll. (Japan)) (and others)

    1989-11-01

    Gadolinium-DTPA (Gd-DTPA) enhances contrast between tissues in magnetic resonance (MR) imaging. The enhancement of tissues depends partly upon the pulse sequences, and the optimal pulse sequence is also influenced by the tissue cncentration of Gd-DTPA. We prepared phantoms of 25% albumin solutions with various concentrations of Gd-DTPA, and imaged them using various pulse sequences with 1.5-T MR system. We also performed MR imaging of 16 patients with tumors (10 brain tumors and 6 hepatic tumors) before and after intravenous administration of Gd-DTPA (0.1 mmol/kg); 6 patients with hepatic tumors underwent dynamic MR imaging during suspended respiration. We made a theoretical equation to calculate the concentration of Gd-DTPA and estimated its tissue concentration in tumors at 0{approx}0.2 mmol/kg. Within these tissue concentrations, the enhancement-to-noise (E/N) ratio was larger in FISP (flip angle of 90deg, TR pf 300 msec, minimal TE) and SE (TR of 400 msec, minimal TE) sequences than in other sequences observed. These sequences may be preferable for conventional enhanced-MRI. Among the pulse sequences with TR of less than 100 msec, FISP (flip angle of 90deg, TR of less than 100 msec, minimal TE) had the largest E/N ratio; which may be useful for dynamic MRI during suspended respiration. The importance of selecting the optimal pulse sequences according to the imaging modality used will be discussed. (author).

  13. MRI

    Science.gov (United States)

    ... the room. Pins, hairpins, metal zippers, and similar metallic items can distort the images. Removable dental work ... an MRI can cause heart pacemakers and other implants not to work as well. The magnets can ...

  14. Comparison of intraductal spread on dynamic contrast-enhanced MRI with clinicopathologic features in breast cancer

    International Nuclear Information System (INIS)

    Komatsu, Shuhei; Lee, Chol-Joo; Hosokawa, Yohei; Ichikawa, Daisuke; Hamashima, Takashi; Shirono, Koichi; Okabe, Harumi; Kurioka, Hideaki; Oka, Takahiro

    2004-01-01

    Contrast-enhanced magnetic resonance imaging (CE-MRI) has emerged as a new diagnostic technology in various breast cancer treatments. However, little is known about the correlation between intraductal spread on CE-MRI and clinicopathologic features. This study was designed to evaluate these correlations for the surgical planning of breast cancer. Twenty-six breast cancer lesions (in 26 female patients) treated by breast conserving surgery between March 2001 and March 2003 were evaluated retrospectively. CE-MRI was performed with a 1.5 T unit using a dedicated bilateral breast coil. In detecting intraductal spread of breast cancer, the sensitivity, specificity and accuracy of CE-MRI were 82.4%, 60.0% and 77.3%, respectively. On mammography (MMG), these were 21.1%, 100.0% and 42.3%, respectively. Therefore, CE-MRI has a higher sensitivity and accuracy, although with a lower specificity than MMG. Compared with breast cancer lesions without intraductal spread on CE-MRI, lesions with intraductal spread on CE-MRI were found more frequently in larger-sized tumors (P=0.0088). Preoperative evaluation for intraductal spread by CE-MRI should be more useful than by MMG for breast cancer. When making the surgical decision regarding excision range, particular attention should be paid to this consideration for patients with larger-sized cancer tumors. (author)

  15. Dynamic contrast-enhanced MRI and sonography in patients receiving primary chemotherapy for breast cancer

    International Nuclear Information System (INIS)

    Montemurro, Filippo; Aglietta, Massimo; Martincich, Laura; Rosa, Giovanni De; Cirillo, Stefano; Marra, Vincenzo; Regge, Daniele; Biglia, Nicoletta; Sismondi, Piero; Gatti, Marco

    2005-01-01

    We compared dynamic contrast-enhanced MRI (DCE-MRI) and sonography (US) for monitoring tumour size in 21 patients with breast cancer undergoing primary chemotherapy (PCT) followed by surgery. The correlation between DCE-MRI and US measurements of tumour size, defined as the product of the two major diameters, was 0.555 (P=0.009), 0.782 (P 2 , P 2 , P=0.009). After PCT, the median tumour size measured by the two techniques was similar (256 vs 289 mm 2 for DCE-MRI and US, respectively, P=0.859). The correlation with the histopathological major tumour diameter was 0.824 (P<0.001) and 0.705 (P<0.001) for post-treatment DCE-MRI and US, respectively. Measurements of the final major tumour diameter by DCE-MRI tended to be more precise, including cases achieving a pathological complete response. Randomized trials are warranted to establish the clinical impact of the initial discrepancy in tumour size estimates between DCE-MRI and US, and the trend towards a better definition of the final tumour size provided by DCE-MRI in this clinical setting. (orig.)

  16. Dynamic contrast-enhanced MRI of benign prostatic hyperplasia and prostatic carcinoma: correlation with angiogenesis

    International Nuclear Information System (INIS)

    Ren, J.; Huan, Y.; Wang, H.; Chang, Y.-J.; Zhao, H.-T.; Ge, Y.-L.; Liu, Y.; Yang, Y.

    2008-01-01

    Aim: To investigate the diagnostic and differential diagnostic values of dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) in prostatic diseases, and to investigate the correlation between the parameters of SI-T curves and angiogenesis. Materials and methods: Twenty-one patients with proven prostatic carcinoma (Pca) and 29 patients with proven benign prostatic hyperplasia (BPH) were examined using DCE MRI. Diagnostic characteristics for differentiation were examined using threshold values for maximum peak time, enhancement degree, and enhancement rate. Then, the signal intensity-time curves (SI-T curves) were analysed, and the correlations between the parameters of SI-T curves and the expression levels of vascular endothelial growth factor (VEGF) and microvascular density (MVD) were investigated. All patients underwent prostatectomy. DCE MRI and histological findings were correlated. Results: Pca showed stronger enhancement with an earlier peak time, higher enhancement, and enhancement rate (p 2 = 13.57, P < 0.005). The VEGF and MVD expression levels of Pca were higher than those of BPH. Peak time was negatively correlated with the expression levels of VEGF and MVD, whereas the enhancement degree and enhancement rate showed positive correlations (Pearson correlation, p < 0.05). Conclusion: Based on T2-weighted imaging, DCE MRI curves can help to differentiate benign from malignant prostate tissue. In the present study the type C curve was rarely seen with malignant disease, but these results need confirmation

  17. Magnetic resonance properties of Gd(III)-bound lipid-coated microbubbles and their cavitation fragments.

    Science.gov (United States)

    Feshitan, Jameel A; Boss, Michael A; Borden, Mark A

    2012-10-30

    Gas-filled microbubbles are potentially useful theranostic agents for magnetic resonance imaging-guided focused ultrasound surgery (MRIgFUS). Previously, MRI at 9.4 T was used to measure the contrast properties of lipid-coated microbubbles with gadolinium (Gd(III)) bound to lipid headgroups, which revealed that the longitudinal molar relaxivity (r(1)) increased after microbubble fragmentation. This behavior was attributed to an increase in water proton exchange with the Gd(III)-bound lipid fragments caused by an increase in the lipid headgroup area that accompanied the lipid shell monolayer-to-bilayer transition. In this article, we explore this mechanism by comparing the changes in r(1) and its transverse counterpart, r(2)*, after the fragmentation of microbubbles consisting of Gd(III) bound to two different locations on the lipid monolayer shell: the phosphatidylethanolamine (PE) lipid headgroup region or the distal region of the poly(ethylene glycol) (PEG) brush. Nuclear magnetic resonance (NMR) at 1.5 T was used to measure the contrast properties of the various microbubble constructs because this is the most common field strength used in clinical MRI. Results for the lipid-headgroup-labeled Gd(III) microbubbles revealed that r(1) increased after microbubble fragmentation, whereas r(2)* was unchanged. An analysis of PEG-labeled Gd(III) microbubbles revealed that both r(1) and r(2)* decreased after microbubble fragmentation. Further analysis revealed that the microbubble gas core enhanced the transverse MR signal (T(2)*) in a concentration-dependent manner but minimally affected the longitudinal (T(1)) signal. These results illustrate a new method for the use of NMR to measure the biomembrane packing structure and suggest that two mechanisms, proton-exchange enhancement by lipid membrane relaxation and magnetic field inhomogeneity imposed by the gas/liquid interface, may be used to detect and differentiate Gd(III)-labeled microbubbles and their cavitation

  18. Contrast-enhanced MRI of intrasellar arachnoid cysts: relationship between the pituitary gland and cyst

    International Nuclear Information System (INIS)

    Nomura, M.; Kanazawa Univ. School of Medicine; Tachibana, O.; Hasegawa, M.; Kohda, Y.; Nakada, M.; Yamashima, T.; Yamashita, J.; Suzuki, M.

    1996-01-01

    We recently encountered two large intrasellar arachnoid cysts extending to the suprasellar region. The intensity of the cyst contents was identical to that of the cerebrospinal fluid on both T1- and T2-weighted MRI. On contrast-enhanced MRI, the pituitary gland was compressed posteroinferiorly and flattened in the sella turcica. In this report of rare intrasellar arachnoid cysts the discussion is focused on dislocation of the pituitary gland. (orig.)

  19. 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....

  20. Correlation of contrast agent kinetics between iodinated contrast-enhanced spectral tomosynthesis and gadolinium-enhanced MRI of breast lesions

    International Nuclear Information System (INIS)

    Froeling, Vera; Diekmann, Felix; Renz, Diane M.; Fallenberg, Eva M.; Steffen, Ingo G.; Diekmann, Susanne; Schmitzberger, Florian F.; Lawaczeck, Ruediger

    2013-01-01

    Assessment of contrast agent kinetics in contrast-enhanced MRI (CE-MRI) with gadolinium-containing contrast agents offers the opportunity to predict breast lesion malignancy. The goal of our study was to determine if similar patterns exist for spectral contrast-enhanced digital breast tomosynthesis (CE-DBT) using an iodinated contrast agent. The protocol of our prospective study was approved by the relevant institutional review board and the German Federal Office for Radiation Protection. All patients provided written informed consent. We included 21 women with a mean age of 62.4 years. All underwent ultrasound-guided biopsy of a suspect breast lesion, spectral CE-DBT and CE-MRI. For every breast lesion, contrast agent kinetics was assessed by signal intensity-time curves for spectral CE-DBT and CE-MRI. Statistical comparison used Cohen's kappa and Spearman's rho test. Spearman's rho of 0.49 showed significant (P = 0.036) correlation regarding the contrast agent kinetics in signal intensity-time curves for spectral CE-DBT and CE-MRI. Cohen's kappa indicated moderate agreement (kappa = 0.438). There is a statistically significant correlation between contrast agent kinetics in the signal intensity-time curves for spectral CE-DBT and CE-MRI. Observing intralesional contrast agent kinetics in spectral CE-DBT may aid evaluation of malignant breast lesions. (orig.)

  1. Comparison of different magnetic resonance cholangiography techniques in living liver donors including Gd-EOB-DTPA enhanced T1-weighted sequences.

    Directory of Open Access Journals (Sweden)

    Sonja Kinner

    Full Text Available Preoperative evaluation of potential living liver donors (PLLDs includes the assessment of the biliary anatomy to avoid postoperative complications. Aim of this study was to compare T2-weighted (T2w and Gd-EOB-DTPA enhanced T1-weighted (T1w magnetic resonance cholangiography (MRC techniques in the evaluation of PLLDs.30 PLLDs underwent MRC on a 1.5 T Magnetom Avanto (Siemens, Erlangen, Germany using (A 2D T2w HASTE (Half Fourier Acquisition Single Shot Turbo Spin Echo fat saturated (fs in axial plane, (B 2D T2w HASTE fs thick slices in coronal plane, (C free breathing 3D T2w TSE (turbo spin echo RESTORE (high-resolution navigator corrected plus (D maximum intensity projections (MIPs, (E T2w SPACE (sampling perfection with application optimized contrasts using different flip angle evolutions plus (F MIPs and (G T2w TSE BLADE as well as Gd-EOB-DTPA T1w images without (G and with (H inversion recovery. Contrast enhanced CT cholangiography served as reference imaging modality. Two independent reviewers evaluated the biliary tract anatomy on a 5-point scale subjectively and objectively. Data sets were compared using a Mann-Whitney-U-test. Kappa values were also calculated.Source images and maximum intensity projections of 3D T2w TSE sequences (RESTORE and SPACE proved to be best for subjective and objective evaluation directly followed by 2D HASTE sequences. Interobserver variabilities were good to excellent (k = 0.622-0.804.3D T2w sequences are essential for preoperative biliary tract evaluation in potential living liver donors. Furthermore, our results underline the value of different MRCP sequence types for the evaluation of the biliary anatomy in PLLDs including Gd-EOB-DTPA enhanced T1w MRC.

  2. Design, synthesis, and evaluation of VEGFR-targeted macromolecular MRI contrast agent based on biotin–avidin-specific binding

    Science.gov (United States)

    Liu, Yongjun; Wu, Xiaoyun; Sun, Xiaohe; Wang, Dan; Zhong, Ying; Jiang, Dandan; Wang, Tianqi; Yu, Dexin; Zhang, Na

    2017-01-01

    Developing magnetic resonance imaging (MRI) contrast agents with high relaxivity and specificity was essential to increase MRI diagnostic sensitivity and accuracy. In this study, the MRI contrast agent, vascular endothelial growth factor receptor (VEGFR)-targeted poly (l-lysine) (PLL)-diethylene triamine pentacetate acid (DTPA)-gadolinium (Gd) (VEGFR-targeted PLL-DTPA-Gd, VPDG), was designed and prepared to enhance the MRI diagnosis capacity of tumor. Biotin-PLL-DTPA-Gd was synthesized first, then, VEGFR antibody was linked to biotin-PLL-DTPA-Gd using biotin–avidin reaction. In vitro cytotoxicity study results showed that VPDG had low toxicity to MCF-7 cells and HepG2 cells at experimental concentrations. In cell uptake experiments, VPDG could significantly increase the internalization rates (61.75%±5.22%) in VEGFR-positive HepG2 cells compared to PLL-DTPA-Gd (PDG) (25.16%±4.71%, P<0.05). In MRI studies in vitro, significantly higher T1 relaxivity (14.184 mM−1 s−1) was observed compared to Magnevist® (4.9 mM−1 s−1; P<0.01). Furthermore, in vivo MRI study results showed that VPDG could significantly enhance the tumor signal intensity and prolong the diagnostic time (from <1 h to 2.5 h). These results indicated that macromolecular VPDG was a promising MRI contrast agent and held great potential for molecular diagnosis of tumor. PMID:28765707

  3. Background parenchymal enhancement on baseline screening breast MRI: impact on biopsy rate and short-interval follow-up.

    LENUS (Irish Health Repository)

    Hambly, Niamh M

    2011-01-01

    Background parenchymal enhancement on breast MRI refers to normal enhancement of the patient\\'s fibroglandular tissue. The aim of this study was to determine the effect of background parenchymal enhancement on short-interval follow-up, biopsy, and cancer detection rate on baseline screening MRI in a high-risk group.

  4. Glucose Administration Enhances fMRI Brain Activation and Connectivity Related to Episodic Memory Encoding for Neutral and Emotional Stimuli

    Science.gov (United States)

    Parent, Marise B.; Krebs-Kraft, Desiree L.; Ryan, John P.; Wilson, Jennifer S.; Harenski, Carla; Hamann, Stephan

    2011-01-01

    Glucose enhances memory in a variety of species. In humans, glucose administration enhances episodic memory encoding, although little is known regarding the neural mechanisms underlying these effects. Here we examined whether elevating blood glucose would enhance functional MRI (fMRI) activation and connectivity in brain regions associated with…

  5. Enhanced conductivity in pulsed laser deposited Ce0.9Gd0.1O2−δ/SrTiO3 heterostructures

    DEFF Research Database (Denmark)

    Kant, K. Mohan; Esposito, Vincenzo; Pryds, Nini

    2010-01-01

    Significant enhancement in the electrical conductivity of Ce0.9Gd0.1O2−δ (CGO) thin films (250 and 500 nm) deposited on MgO(001) substrate is observed by introducing ∼ 50 nm thin SrTiO3 buffer layer film. Introduction of the buffer layer is found to form epitaxial films, leading to minimal grain...... boundary network that results in a free conduction path with near-zero blocking effects perpendicular to current flow. The in-plane conductivity measurements confirm increase in conductivity with increase in compressive strain on CGO films. © 2010 American Institute of Physics...

  6. Experimental bacterial meningitis in rabbit; evaluation with CT and MRI

    International Nuclear Information System (INIS)

    Seo, Jeong Jin; Kang, Heoung Keun; Chu, Sung Nam; Kim, Yun Hyeon; Jeong, Yong Yeon; Chung, Hyon De

    1996-01-01

    The purpose of this study was to evaluate the usefulness of computed tomography(CT) and magnetic resonance imaging(MRI) in experimental bacterial meningitis. CT and MR images of experimental bacterial meningitis were obtained after inoculation of 1ml suspension of 10-6/ml Staphylococcus aureus directly into the supratentorial arachnoid space of 18 New Zealand white rabbits. Each animal was studied with both pre-enhanced and post-enhanced CT and MRI at 12, 24, 48 hours and 1 week. Cerebrospinal fluid of all of 18 rabbits were sampled and cultured for bacterial growth. All of 18 rabbits had the clinical symptoms such as neck stiffness and anorexia within 24 hours after the inoculation. Cerebrospinal fluid cultures were positive for Staphylococcus aureus growth. Gd-enhanced MRI exhibited diffuse enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement ratio(CER) at supratentorial meninges increased to 1.93 at 12 hours and 2.99 at 24 hours from 1.06 at 0 hour. Histologic evaluation demonstrated inflammatory cell infiltration into the meninges. MRI also identified the complications of meningitis such as ependymitis and hydrocephalus more effectively than CT. These results indicated that Fd-enhanced MRI detectred earlier the abnormal findingfs of bacterial meningitis and evaluated more effectively the complications of meningitis compared with CT. MRI was more useful than CT in evaluation of the bacterial meningitis

  7. Experimental bacterial meningitis in rabbit; evaluation with CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Jin; Kang, Heoung Keun; Chu, Sung Nam; Kim, Yun Hyeon; Jeong, Yong Yeon; Chung, Hyon De [Chonnam Univ. Medical School, Kwangju (Korea, Republic of)

    1996-01-01

    The purpose of this study was to evaluate the usefulness of computed tomography(CT) and magnetic resonance imaging(MRI) in experimental bacterial meningitis. CT and MR images of experimental bacterial meningitis were obtained after inoculation of 1ml suspension of 10-6/ml Staphylococcus aureus directly into the supratentorial arachnoid space of 18 New Zealand white rabbits. Each animal was studied with both pre-enhanced and post-enhanced CT and MRI at 12, 24, 48 hours and 1 week. Cerebrospinal fluid of all of 18 rabbits were sampled and cultured for bacterial growth. All of 18 rabbits had the clinical symptoms such as neck stiffness and anorexia within 24 hours after the inoculation. Cerebrospinal fluid cultures were positive for Staphylococcus aureus growth. Gd-enhanced MRI exhibited diffuse enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement along the thickened supratentorial meninges earlier than CT. In Gd-enhanced MRI, the mean contrast enhancement ratio(CER) at supratentorial meninges increased to 1.93 at 12 hours and 2.99 at 24 hours from 1.06 at 0 hour. Histologic evaluation demonstrated inflammatory cell infiltration into the meninges. MRI also identified the complications of meningitis such as ependymitis and hydrocephalus more effectively than CT. These results indicated that Fd-enhanced MRI detectred earlier the abnormal findingfs of bacterial meningitis and evaluated more effectively the complications of meningitis compared with CT. MRI was more useful than CT in evaluation of the bacterial meningitis.

  8. Polyethylene glycol-covered ultra-small Gd2O3 nanoparticles for positive contrast at 1.5 T magnetic resonance clinical scanning

    Science.gov (United States)

    Fortin, Marc-André; Petoral, Rodrigo M., Jr.; Söderlind, Fredrik; Klasson, A.; Engström, Maria; Veres, Teodor; Käll, Per-Olof; Uvdal, Kajsa

    2007-10-01

    The size distribution and magnetic properties of ultra-small gadolinium oxide crystals (US-Gd2O3) were studied, and the impact of polyethylene glycol capping on the relaxivity constants (r1, r2) and signal intensity with this contrast agent was investigated. Size distribution and magnetic properties of US-Gd2O3 nanocrystals were measured with a TEM and PPMS magnetometer. For relaxation studies, diethylene glycol (DEG)-capped US-Gd2O3 nanocrystals were reacted with PEG-silane (MW 5000). Suspensions were adequately dialyzed in water to eliminate traces of Gd3+ and surfactants. The particle hydrodynamic radius was measured with dynamic light scattering (DLS) and the proton relaxation times were measured with a 1.5 T MRI scanner. Parallel studies were performed with DEG-Gd2O3 and PEG-silane-SPGO (Gd2O3,DTPA and the r2/r1 ratio was 1.4. PEG-silane-SPGO gave low r1 relaxivities and high r2/r1 ratios, less compatible with positive contrast agent requirements. Higher r1 were obtained with PEG-silane in comparison to DEG-