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Sample records for contrast medium administration

  1. Evaluation of changes in vertebral body density following administration of contrast medium during routine CT examination

    International Nuclear Information System (INIS)

    Janicek, M.; Bruna, J.; Stenhova, H.

    1984-01-01

    The possibility is discussed of depicting changes in the density of spongiosis of the vertebral body in normal patients after intravenous administration of a bolus of 40 ml 60% Diazetrizoate in the course of a routine CT examination. The average increase in density immediately after the administration of the contrast medium is 12 H (8%), in the course of 10 minutes is reduced to 5 H (4%) against the initial values in native examination. These average changes are statistically significant, in individual patients, however, the increase in density following the administration of a contrast medium fluctuates considerably (from 0.7% to 10%). Only systematic comparison with various pathological conditions will make it possible to assess the possibilities of the evaluation of the structure of the vertebral body in routine CT with the administration of a contrast medium into the blood flow. (author)

  2. Local blood-brain barrier penetration following systemic contrast medium administration

    International Nuclear Information System (INIS)

    Utz, R.; Ekholm, S.E.; Isaac, L.; Sands, M.; Fonte, D.

    1988-01-01

    The present study was initiated by a severe complication in a patient with renal dysfunction who developed cortical blindness and weakness of her left extremities 30 hours following renal and abdominal angiography. To evaluate the impact of prolonged high serum concentrations of contrast medium (CM) this clinical situation was simulated in a laboratory model using sheep with elevated serum levels of contrast medium maintained for 48 hours. The experimental data did not support the theory that the prolonged exposure to high circulating levels of contrast medium (4 ml/kg body weight of meglumine diatrizoate 60%) is sufficient alone to cause penetration of the blood-brain barrier. (orig.)

  3. The association between use of metformin and change in serum CO_2 level after administration of contrast medium

    International Nuclear Information System (INIS)

    Kim, S.K.; Jung, J.; Jung, J.H.; Kim, K.Y.; Baek, J.-H.; Hahm, J.R.

    2016-01-01

    Aim: To evaluate the changes in serum creatinine and total CO_2 levels in patients receiving metformin during administration of contrast medium. Materials and methods: Patient records from January 2012 to December 2012 after the administration of contrast medium were reviewed retrospectively. A total of 924 patients were included for the final analysis. Of them, 105 received metformin during contrast medium administration, 112 were taking other oral hypoglycaemic agents, and 707 patients were not diabetic (controls). Results: No significant change in total CO_2 levels was detected (p=0.678). Metabolic acidosis was present in 33 (31.4%) metformin users, 31 (28.6%) other oral hypoglycaemic agent users, and 153 (21.6%) control patients. In the present logistic regression analysis, age, baseline levels of creatinine, and total CO_2 levels were associated with metabolic acidosis after contrast medium exposure. Conclusion: These data indicate the presence of a coexisting risk factor, other than metformin use, associated with metabolic acidosis after contrast medium exposure. No relationship was found between the use of metformin and metabolic acidosis during contrast medium exposure. - Highlights: • The use of metformin was not associated with metabolic acidosis after contrast exposure. • The coexisting risk factors for metabolic acidosis were present in patient with metabolic acidosis after contrast exposure. • There is a need to consider the maintenance of metformin during a CT scan in patients with a low risk for lactic acidosis.

  4. Duplex-assisted carotid artery stenting without administration of contrast medium for patients with chronic kidney disease or allergic reaction.

    Science.gov (United States)

    Mizowaki, Takashi; Fujita, Atsushi; Imahori, Taichiro; Uyama, Atsushi; Inoue, Satoshi; Kohta, Masaaki; Hamaguchi, Hirotoshi; Sasayama, Takashi; Hosoda, Kohkichi; Kohmura, Eiji

    2016-07-01

    We aimed to investigate the safety and feasibility of duplex-assisted carotid artery stenting (CAS) without administration of contrast medium for the prevention of adverse reactions. Fifteen patients (9 % of all CASs) with severe carotid stenosis (≥70 %) associated with chronic kidney disease (CKD) (stage ≥3) or allergy to contrast medium underwent duplex-assisted CAS without administration of contrast medium over 4 years. The procedural success rate and perioperative complication rates were compared between the duplex-assisted CAS (n = 15) and conventional CAS (n = 153) groups. The technical success rate was 100 % in both groups. Combined stroke or death rates during the post-procedural period did not differ significantly between the duplex-assisted CAS group (0/15, 0 %) and conventional CAS group (4/153, 2.6 %). None of the 14 patients with CKD in the duplex-assisted CAS group experienced further deterioration of renal function. The mean surface radiation dose of participants in the duplex-assisted CAS group (n = 13, 312 ± 131 mGy) was significantly lower than that of the conventional CAS group (n = 31, 1036 ± 571 mGy) (p duplex-assisted CAS group (156 ± 39.7 min) and the conventional CAS group (156 ± 37.4 min). Duplex-assisted CAS without administration of contrast medium could be an alternative option in selected patients deemed to be at high risk for renal failure from nephrotoxic contrast medium or who have an allergy to contrast medium.

  5. In which patients should serum creatinine be measured before iodinated contrast medium administration?

    International Nuclear Information System (INIS)

    Thomsen, Henrik S.

    2005-01-01

    Routine measurement of serum creatinine before injection of intravascular iodinated contrast material in all patients would be cumbersome and have an associated cost. There is doubt about whether serum creatinine should be measured routinely in all patients or selectively. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and draw up guidelines on this important practical issue. A literature search was carried out and summarized in a report. Based on the available information and discussions amongst the members of the Committee, guidelines were produced. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain. The practice for identifying patients at risk of contrast medium induced nephropathy varies considerably from one institution to another. Patients at risk constitute only a small percentage of all cases referred for contrast enhanced imaging examination. However, it is important to identify them and take the necessary precautions. Recent serum creatinine level should be available in patients with an increased probability of a raised serum creatinine level (renal disease, renal surgery, proteinuria, diabetes mellitus, hypertension, gout, current intake of nephrotoxic drugs). A simple guideline has been produced. (orig.)

  6. In which patients should serum creatinine be measured before iodinated contrast medium administration?

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, Henrik S. [Copenhagen University Hospital, Herlev (Denmark). Department of Diagnostic Radiology; Morcos, Sameh K. [Northern General Hospital, Department of Diagnostic Imaging, Sheffield Teaching Hospitals NHS Trust, Sheffield (United Kingdom)

    2005-04-01

    Routine measurement of serum creatinine before injection of intravascular iodinated contrast material in all patients would be cumbersome and have an associated cost. There is doubt about whether serum creatinine should be measured routinely in all patients or selectively. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and draw up guidelines on this important practical issue. A literature search was carried out and summarized in a report. Based on the available information and discussions amongst the members of the Committee, guidelines were produced. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain. The practice for identifying patients at risk of contrast medium induced nephropathy varies considerably from one institution to another. Patients at risk constitute only a small percentage of all cases referred for contrast enhanced imaging examination. However, it is important to identify them and take the necessary precautions. Recent serum creatinine level should be available in patients with an increased probability of a raised serum creatinine level (renal disease, renal surgery, proteinuria, diabetes mellitus, hypertension, gout, current intake of nephrotoxic drugs). A simple guideline has been produced. (orig.)

  7. Roentgen contrast medium

    International Nuclear Information System (INIS)

    Tamborski, C.

    1989-01-01

    The patent deals with a roentgen contrast medium containing a perfluorinebrominealkylether of the formula C m F 2m+1 OC n F 2n Br dispersed in water, preferentially in the presence of a non-ionic dispersing agent such as a fluorinated amidoaminoxide. 2 tabs

  8. MRI with intrathecal MRI gadolinium contrast medium administration: a possible method to assess glymphatic function in human brain

    International Nuclear Information System (INIS)

    Eide, Per Kristian; Ringstad, Geir

    2015-01-01

    Recently, the “glymphatic system” of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol, which distributed throughout her entire brain after 1 and 4.5 h. MRI with intrathecal Gd may become a tool to study glymphatic function in the human brain

  9. MRI with intrathecal MRI gadolinium contrast medium administration: a possible method to assess glymphatic function in human brain.

    Science.gov (United States)

    Eide, Per Kristian; Ringstad, Geir

    2015-11-01

    Recently, the "glymphatic system" of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol, which distributed throughout her entire brain after 1 and 4.5 h. MRI with intrathecal Gd may become a tool to study glymphatic function in the human brain.

  10. Intravenous Contrast Medium Administration for Computed Tomography Scan in Emergency: A Possible Cause of Contrast-Induced Nephropathy

    International Nuclear Information System (INIS)

    Sonhaye, Lantam; Kolou, Bérésa; Tchaou, Mazamaesso; Amadou, Abdoulatif; Assih, Kouméabalo; N'Timon, Bidamin; Adambounou, Kokou; Agoda-Koussema, Lama; Adjenou, Komlavi; N'Dakena, Koffi

    2015-01-01

    The goal of this study was to assess risk for CIN after CT Scan during an emergency and to identify risk factors for the patient. Prospective review of all patients admitted to the emergency room (ER) of the Teaching Hospital of Lomé (Togo) during a 2-year period. CIN was defined as an increase in serum creatinine by 0.5 mg/dL from admission after undergoing CT Scan with intravenous contrast. A total of 620 patients underwent a CT Scan in the emergency room using intravenous contrast and 672 patients took the CT Scan without intravenous contrast. Out of the patients who received intravenous contrast for CT Scan, three percent of them developed CIN during their admission. Moreover, upon discharge no patient had continued renal impairment. No patient required dialysis during their admission. The multivariate analysis of all patients who had serial creatinine levels (including those who did not receive any contrast load) shows no increased risk for acute kidney injury associated intravenous contrast (odds ratio = 0.619, p value = 0.886); only diabetes remains independent risk factor of acute kidney injury (odds ratio = 6.26, p value = 0.031)

  11. Intravenous contrast medium administration at 128 multidetector row CT pulmonary angiography: Bolus tracking versus test bolus and the implications for diagnostic quality and effective dose

    International Nuclear Information System (INIS)

    Rodrigues, J.C.L.; Mathias, H.; Negus, I.S.; Manghat, N.E.; Hamilton, M.C.K.

    2012-01-01

    Aim: To investigate the effects of a test bolus protocol contrast medium administration on diagnostic image quality in computed tomography pulmonary angiography (CTPA). Materials and methods: Fifty patients referred for exclusion of pulmonary embolism underwent CTPA using a test bolus protocol CTPA at 120 kVp and were compared with 50 patients undergoing CTPA using a standard bolus-tracking protocol at 120 kVp, via assessment of attenuation, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) seen in the pulmonary arteries (PAs). An additional group of 10 non-obese patients who underwent CTPA using a test bolus protocol performed at 100 kVp were also analysed. Mean effective dose was calculated from the dose–length product, using standard conversion factors. Results: The test bolus protocol showed significantly higher attenuation, SNR, and CNR in the pulmonary vasculature down to the segmental level compared to bolus-tracking CTPA (p < 0.0001). There was no significant difference in effective dose between the test bolus and bolus tracking cohorts. The additional group of test bolus CTPA examinations performed at 100 kVp had a significantly reduced effective dose in comparison to both test bolus CTPA at 120 kVp and bolus-tracking CTPA at 120 kVp (p < 0.005) yet maintained mean PA attenuation to segmental level significantly better than bolus-tracking CTPA performed at 120 kVp and comparable to the test bolus cohort performed at 120 kVp. Conclusion: Test bolus contrast administration should be used as an optimal protocol. Performing test bolus CTPA at 100 kVp, as opposed to 120 kVp, significantly reduces dose without compromising PA attenuation in non-obese subjects.

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

    Science.gov (United States)

    Arvanitis, C. D.; Speller, R.

    2009-10-01

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

  13. Incompatibility of Contrast Medium and Trisodium Citrate

    International Nuclear Information System (INIS)

    Delcour, Christian; Bruninx, Guy

    2013-01-01

    To test the compatibility of trisodium citrate, a catheter lock solution, with iodinated contrast medium. Iohexol, iobitridol, iodixanol, ioxaglate, ioxithalamate, iomeprol, and iopromide were tested. In all tests, 2 ml of contrast medium were mixed with 2 ml of trisodium citrate solution. Iodixanol and ioxaglate provoked a highly viscous gluelike precipitation when mixed with trisodium citrate. A brief transient precipitate was observed with iohexol, iomeprol, and ioxithalamate. Permanent precipitation occurred with iobitridol and iopromide. One must be aware of the potential for precipitation when contrast medium is mixed with trisodium citrate solution. Before trisodium citrate solution is injected, the catheter should be thoroughly flushed with saline if a contrast medium has previously been injected through it.

  14. Multidetector computed tomography with triple-bolus contrast medium administration protocol for preoperative anatomical and functional assessment of potential living renal donors

    International Nuclear Information System (INIS)

    Knox, Matthew K.; Rivers-Bowerman, Michael D.; Bardgett, Harry P.; Cowan, Nigel C.

    2010-01-01

    To evaluate multidetector computed tomography (MDCT) with a triple-bolus contrast administration protocol for preoperative anatomical and functional assessment of living renal donors. Fifty-five potential living renal donors underwent MDCT of which 27 proceeded to donor nephrectomy. A triple-bolus contrast administration protocol was used for simultaneous acquisition of arterial, nephrographic, and excretory phases. MDCT images were independently reviewed in random order by two radiologists blinded to surgical anatomy findings. Diagnostic accuracy for anatomical variants was quantified by sensitivity and specificity. Differential renal function (DRF) was derived from MDCT for 54 patients and compared with technetium-99 m dimercaptosuccinic acid renography (Tc-99 m DMSA). All triple-bolus MDCT examinations were technically adequate. Accessory renal arteries and veins were identified at surgery in 33% (n = 9/27) and 22% (n = 6/27) of donor kidneys. The mean difference between MDCT-derived DRF and DMSA was 0.8% (95% CI 0.1-1.6) with 95% limits of agreement of -4.6% (95% CI -3.3 to -5.9) to 6.3% (95% CI 5.0-7.6). MDCT delivered a mean (SD, range) radiation dose of 9.5 (3.6, 3.6-17.3) mSv. MDCT with a triple-bolus contrast administration provides accurate anatomical and functional evaluation of living renal donors. (orig.)

  15. Multidetector computed tomography with triple-bolus contrast medium administration protocol for preoperative anatomical and functional assessment of potential living renal donors

    Energy Technology Data Exchange (ETDEWEB)

    Knox, Matthew K. [University of Calgary, Faculty of Medicine, UME Office, Health Sciences Centre, Calgary, Alberta (Canada); Rivers-Bowerman, Michael D. [University of British Columbia, Faculty of Medicine, MD Undergraduate Program, Diamond Health Care Centre, Vancouver, British Columbia (Canada); Bardgett, Harry P. [Bradford Teaching Hospitals, Department of Radiology, Bradford (United Kingdom); Cowan, Nigel C. [The Churchill Hospital, Department of Radiology, Oxford (United Kingdom)

    2010-11-15

    To evaluate multidetector computed tomography (MDCT) with a triple-bolus contrast administration protocol for preoperative anatomical and functional assessment of living renal donors. Fifty-five potential living renal donors underwent MDCT of which 27 proceeded to donor nephrectomy. A triple-bolus contrast administration protocol was used for simultaneous acquisition of arterial, nephrographic, and excretory phases. MDCT images were independently reviewed in random order by two radiologists blinded to surgical anatomy findings. Diagnostic accuracy for anatomical variants was quantified by sensitivity and specificity. Differential renal function (DRF) was derived from MDCT for 54 patients and compared with technetium-99 m dimercaptosuccinic acid renography (Tc-99 m DMSA). All triple-bolus MDCT examinations were technically adequate. Accessory renal arteries and veins were identified at surgery in 33% (n = 9/27) and 22% (n = 6/27) of donor kidneys. The mean difference between MDCT-derived DRF and DMSA was 0.8% (95% CI 0.1-1.6) with 95% limits of agreement of -4.6% (95% CI -3.3 to -5.9) to 6.3% (95% CI 5.0-7.6). MDCT delivered a mean (SD, range) radiation dose of 9.5 (3.6, 3.6-17.3) mSv. MDCT with a triple-bolus contrast administration provides accurate anatomical and functional evaluation of living renal donors. (orig.)

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

    International Nuclear Information System (INIS)

    Terasawa, Kazuaki; Hatcho, Atsushi; Okuda, Itsuko

    2011-01-01

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

  17. Radiculography with reduced amounts of contrast medium

    International Nuclear Information System (INIS)

    Signorini, E.; Caputo, N.; Chiurulla, C.; Ciorba, E.; Pelliccioli, G.P.; Cianciulli, E.

    1984-01-01

    Because of the frequency and seriousness of side effects observed after radiculography, due to, among the other things, the amount of contrast medium, the authors describe a method that gives diagnostically satisfactory results using a low dose of contrast and a tangent-beam technique. Among 106 patients undergoing radiculography with a tangent-beam technique and Iopamidol, only 4 developed mild side effects, namely headache in three cases and headache with nausea in one. (Author)

  18. Radiculography with water-soluble contraste medium

    International Nuclear Information System (INIS)

    Araujo Pinheiro, R.S. de

    1987-01-01

    The etiologic diagnosis of the lumbar pain is discussed. The radiculography with water-soluble contrast medium is used and 250 cases are studied. Some practical criteria of indication executation and interpretation of the examination are reported. (M.A.C.) [pt

  19. Contrast medium-induced nephropathy: the pathophysiology

    DEFF Research Database (Denmark)

    Persson, P B; Tepel, Martin

    2006-01-01

    A widespread, rather general, definition of contrast-induced nephropathy (CIN) is an impairment in renal function occurring within 3 days following the intravascular administration of contrast media (CM) and the absence of an alternative aetiology. In spite of the vast clinical importance of CIN...... haemodynamics, regional hypoxia, auto-, and paracrine factors (adenosine, endothelin, reactive oxygen species) to direct cytotoxic effects. Although these potential mediators of CIN will be discussed separately, several factors may act in concert to perturb kidney function after exposure to contrast media. From...... the current knowledge of the mechanisms causing CIN, it is not possible to recommend a certain class of contrast media, except to avoid large doses of CM of the first generation. From a pathophysiological perspective, volume expansion is effective in avoiding CIN, since water permeability of the collecting...

  20. [Observing the density increase curve after intravenous contrast medium administration using a bolus triggering system: a method for detection cardiovascular disorders?].

    Science.gov (United States)

    Stückle, C A; Kickuth, R; Kirchner, E M; Liermann, D; Kirchner, J

    2002-06-01

    Recently bolus tracking systems were developed to improve the timing of intravenous contrast media application in helical computed tomography. We investigated the benefit of this new method as a parameter of the cardiac function. Retrospective analysis of 64 patients which incidentally underwent bolus triggered contrast enhanced helical CT and invasive investigation of the heart within one week. All examinations were performed on the CT scanner Somatom Plus 4 Volume Zoom (Siemens Corp., Forchheim, Germany) using the C.A.R.E. Bolus software. This performs repetitive low-dose test scans (e.g. for the abdomen: 140 kV, 20 mA, Tl 0.5 s) and measures the Hounsfield attenuation (increase over the baseline) in a preselected region of interest. The displayed increase of vascular density over the time after peripheral contrast media injection (75 ml lopromid (300 mg/ml), 2 ml/s) was categorised to three types: (a) rapid increase, (b) deceleration before a 100 HE threshold was reached and (c) one or more peaks. The findings of the invasive investigation of the heart were correlated to the findings of the bolus-tracking measurements. The examinations were categorized as follows: 19 type A, 34 type B, 11 type C. We found a high significant correlation between the type of the Hounsfield attenuation and systolic pressure in the left ventricle. There was no correlation between the type of the Hounsfield attenuation and the diastolic pressure in the left ventricle, the pressures related to the right ventricle or the ejection fraction. The bolus-tacking system showed a sensitivity of 53, a specificity of 82, an accuracy of 70%, a positive predictive value of 70% and a negative predictive value of 70% in detection of left heart failure. The bolus tracking system C.A.R.E.-bolus often shows atypical Hounsfield attenuation in cases of cardiac failure but is not suitable as a screening method of the cardiopulmonary function.

  1. The value of fat saturation sequences and contrast medium administration in MRI of degenerative disease of the posterior/perispinal elements of the lumbosacral spine

    Energy Technology Data Exchange (ETDEWEB)

    D' Aprile, P. [San Paolo Hospital, Department of Neuroradiology, Bari (Italy); U.O. Radiologia, Sezione di Neuroradiologia, Ospedale ' ' S. Paolo' ' , Via Caposcardicchio, Bari (Italy); Tarantino, A. [San Paolo Hospital, Department of Neuroradiology, Bari (Italy); Jinkins, J.R. [State University of New York, Department of Radiology, Downstate Medical Center, Brooklyn, NY (United States); Brindicci, D. [San Paolo Hospital, Department of Radiology, Bari (Italy)

    2007-02-15

    Degenerative-inflammatory lumbar spinal pathology is one of the most common reasons why individuals seek medical care, and low back pain is the main symptom among those most commonly associated with this pathologic condition. Pain is commonly attributed to degenerative disc disease, particularly herniated discs, but many different spinal and perispinal structures may undergo degenerative-inflammatory phenomena and produce pain: discs, bone, facet joints, ligaments and muscles. In particular, in patients with non-radicular low back pain, this syndrome may arise from changes of the posterior elements/perispinal tissues of the lumbar spine (i.e., the ''posterior vertebral compartment''). They include: facet joint pathology (e.g., osteoarthritis, joint effusion, synovitis and synovial cysts), spondylolysis, spinal/perispinal ligamentous degenerative-inflammatory changes and perispinal muscular changes. It is well known that magnetic resonance is the most sensitive imaging method for the evaluation of spinal degenerative pathology, even in the initial stages of the disease. T2-weighted sequences with fat saturation, and when indicated the use of contrast-enhanced T1-weighted images with fat saturation, permit the visualization of degenerative-inflammatory changes of the posterior elements of the lumbar spine that in most cases would have been overlooked with conventional non-fat suppressed imaging. (orig.)

  2. The value of fat saturation sequences and contrast medium administration in MRI of degenerative disease of the posterior/perispinal elements of the lumbosacral spine

    International Nuclear Information System (INIS)

    D'Aprile, P.; Tarantino, A.; Jinkins, J.R.; Brindicci, D.

    2007-01-01

    Degenerative-inflammatory lumbar spinal pathology is one of the most common reasons why individuals seek medical care, and low back pain is the main symptom among those most commonly associated with this pathologic condition. Pain is commonly attributed to degenerative disc disease, particularly herniated discs, but many different spinal and perispinal structures may undergo degenerative-inflammatory phenomena and produce pain: discs, bone, facet joints, ligaments and muscles. In particular, in patients with non-radicular low back pain, this syndrome may arise from changes of the posterior elements/perispinal tissues of the lumbar spine (i.e., the ''posterior vertebral compartment''). They include: facet joint pathology (e.g., osteoarthritis, joint effusion, synovitis and synovial cysts), spondylolysis, spinal/perispinal ligamentous degenerative-inflammatory changes and perispinal muscular changes. It is well known that magnetic resonance is the most sensitive imaging method for the evaluation of spinal degenerative pathology, even in the initial stages of the disease. T2-weighted sequences with fat saturation, and when indicated the use of contrast-enhanced T1-weighted images with fat saturation, permit the visualization of degenerative-inflammatory changes of the posterior elements of the lumbar spine that in most cases would have been overlooked with conventional non-fat suppressed imaging. (orig.)

  3. Risk of application of contrast medium in computed tomography

    International Nuclear Information System (INIS)

    Wende, S.; Speck, U.; Schering A.G., Berlin

    1981-01-01

    The paper deals with the risk associated with the application of contrast medium in CT. The risk is to be seen in intolerance reactions, such as allergic or circulatory reactions and neurotoxic side-effects. In this paper the problems of renal failure caused by the injection of contrast medium are given special attention. Furthermore an iodine-induced hyperthyreosis might result. Especially the possible disturbance of the kidney function means that contrast medium should not be applied arbitrarily and that the examination should be done only by experienced staff. Furthermore the indication for the application of contrast medium in CT should be strictly qualified. (orig.) [de

  4. Risk of application of contrast medium in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wende, S.; Speck, U.

    1981-06-01

    The paper deals with the risk associated with the application of contrast medium in CT. The risk is to be seen in intolerance reactions, such as allergic or circulatory reactions and neurotoxic side-effects. In this paper the problems of renal failure caused by the injection of contrast medium are given special attention. Furthermore an iodine-induced hyperthyreosis might result. Especially the possible disturbance of the kidney function means that contrast medium should not be applied arbitrarily and that the examination should be done only by experienced staff. Furthermore the indication for the application of contrast medium in CT should be strictly qualified.

  5. Magnetic resonance tomography of the orbit: First experiences with the paramagnetic contrast medium gadolinium-DTPA

    International Nuclear Information System (INIS)

    Markl, A.; Vogl, T.; Scheidhauer, K.; Riedel, K.G.; Oeckler, R.

    1986-01-01

    In 21 patients with orbital mass lesions MRI was performed before and after administration of paramagnetic contrast medium, gadolinium-DPTA. In comparison to the plain scan the differentiation of the tumorous tissue against the surrounding structures was improved after application of contrast medium despite a partially moderate increase in signal intensity. Especially highly vascular tumors and vessel diseases show a significant contrast enhancement. With increasing experience in larger number of patients a tissue differentiation seems to be possible. (orig.) [de

  6. Death following intravascular administration of contrast media

    International Nuclear Information System (INIS)

    Shehadi, W.H.

    1985-01-01

    Adverse reactions to intravascularly administered contrast media preceding death and the autopsy findings in 44 patients are presented. There is a wide scatter of the age distribution of fatal reactions. The highest incidence is in the 50-70 year age group. Similar observations were obtained from the 405 deaths due to contrast media reported to the Food and Drug Administration of the United States. In the same age group the number of reactions is highest, likewise the autopsy findings. The predominant autopsy findings are pulmonary edema, congestion and hemorrhage; arteriosclerosis, both general and coronary. In the younger age group the autopsy findings are limited mostly to the respiratory tract. Fatal reactions to contrast media occur often without warning and most deaths occur within 15 min to 6 hours. Reactions to contrast media occur without relation to sex or age. (orig.)

  7. Contrast-medium-induced nephropathy: is there a new consensus? A review of published guidelines

    International Nuclear Information System (INIS)

    Thomsen, Henrik S.; Morcos, Sameh K.

    2006-01-01

    The interest in contrast-medium-induced nephropathy has increased considerably during the last few years. Various guidelines regarding identifying patients at risk and measures to reduce the incidence of this complication have been proposed. The aim of this review was to analyse whether there is some consistency amongst these guidelines. A Medline search for the keyword ''contrast medium induced nephropathy'' during the period from the beginning of 2003 through the end of September 2005 was carried out. Only papers in English were reviewed. Thirteen guidelines were identified. Inconsistency was observed regarding advise on the prophylactic use of drugs and the isoosmolar dimer to reduce the incidence of contrast-medium-induced nephropathy. Consistency was found in relation to the importance of hydration, cessation of intake of nephrotoxic drugs and administration of the lowest possible dose of contrast medium. No new consensus has been observed in comparison to the European Society for Urogenital Radiology (ESUR) guidelines, which were published in 1999. (orig.)

  8. Contrast medium-induced nephropathy: Aspects on incidence ...

    African Journals Online (AJOL)

    Contrast media-induced nephropathy (CIN) is a well-known complication of radiological examinations employing iodine contrast media (I-CM). The rapid development and frequent use of coronary interventions and multi-channel detector computed tomography with concomitant administration of relatively large doses of ...

  9. Extravasation of contrast medium into the gastrointestinal tract following lymphangiography

    International Nuclear Information System (INIS)

    Mihara, K.; Koga, K.; Tsurudome, H.; Nakano, T.; Hoshi, H.; Yamada, H.; Kawahira, K.; Inakura, M.; Watanabe, K.; Haraguchi, Y.

    1981-01-01

    Two cases with roentgenologic findings of extravasation of contrast medium into the stomach and colon following lymphangiography are presented. One is clinically diagnosed as primary intestinal lymphangiectasia; the other as retroperitoneal spread from uterine cancer. The significance of lymphangiography in gastrointestinal or retroperitoneal disorders is discussed. (orig.)

  10. Extravasation of contrast medium into the gastrointestinal tract following lymphangiography

    Energy Technology Data Exchange (ETDEWEB)

    Mihara, K.; Koga, K.; Tsurudome, H.; Nakano, T.; Hoshi, H.; Yamada, H.; Kawahira, K.; Inakura, M.; Watanabe, K.; Haraguchi, Y.

    1981-07-15

    Two cases with roentgenologic findings of extravasation of contrast medium into the stomach and colon following lymphangiography are presented. One is clinically diagnosed as primary intestinal lymphangiectasia; the other as retroperitoneal spread from uterine cancer. The significance of lymphangiography in gastrointestinal or retroperitoneal disorders is discussed.

  11. Extravasation of contrast medium during CT examination: An ...

    African Journals Online (AJOL)

    2013-03-31

    Extravasation of contrast medium during CT examination: An observational casecontrol study. ... Methods: every incident of extravasation which occurred between March 2012 and March 31, 2013 was recorded in an extravasation form. Ethics Committee approval was obtained and the patients gave their consent to ...

  12. Potential mechanisms behind contrast medium-induced nephropathy

    African Journals Online (AJOL)

    How contrast medium-induced nephropathy (CIN) comes about is poorly understood, although CIN is a common cause of acute renal failure. Hitherto, the various studies performed have led to different interpretations and partially contradictory conclusions. This article aimed to review the mechanisms underlying CIN and to ...

  13. Targeting cancer chemotherapeutic agents by use of lipiodol contrast medium

    International Nuclear Information System (INIS)

    Konno, T.

    1990-01-01

    Arterially administered Lipiodol Ultrafluid contrast medium selectively remained in various malignant solid tumors because of the difference in time required for the removal of Lipiodol contrast medium from normal capillaries and tumor neovasculature. Although blood flow was maintained in the tumor, even immediately after injection Lipiodol contrast medium remained in the neovasculature of the tumor. To target anti-cancer agents to tumors by using Lipiodol contrast medium as a carrier, the characteristics of the agents were examined. Anti-cancer agents had to be soluble in Lipiodol, be stable in it, and separate gradually from it so that the anti-cancer agents would selectively remain in the tumor. These conditions were found to be necessary on the basis of the measurement of radioactivity in VX2 tumors implanted in the liver of 16 rabbits that received arterial injections of 14C-labeled doxorubicin. Antitumor activities and side effects of arterial injections of two types of anti-cancer agents were compared in 76 rabbits with VX2 tumors. Oily anti-cancer agents that had characteristics essential for targeting were compared with simple mixtures of anti-cancer agents with Lipiodol contrast medium that did not have these essential characteristics. Groups of rabbits that received oily anti-cancer agents responded significantly better than groups that received simple mixtures, and side effects were observed more frequently in the groups that received the simple mixtures. These results suggest that targeting of the anti-cancer agent to the tumor is important for treatment of solid malignant tumors

  14. Optical tracking of contrast medium bolus to optimize bolus shape and timing in dynamic computed tomography

    International Nuclear Information System (INIS)

    Eisa, Fabian; Brauweiler, Robert; Peetz, Alexander; Hupfer, Martin; Nowak, Tristan; Kalender, Willi A

    2012-01-01

    One of the biggest challenges in dynamic contrast-enhanced CT is the optimal synchronization of scan start and duration with contrast medium administration in order to optimize image contrast and to reduce the amount of contrast medium. We present a new optically based approach, which was developed to investigate and optimize bolus timing and shape. The time-concentration curve of an intravenously injected test bolus of a dye is measured in peripheral vessels with an optical sensor prior to the diagnostic CT scan. The curves can be used to assess bolus shapes as a function of injection protocols and to determine contrast medium arrival times. Preliminary results for phantom and animal experiments showed the expected linear behavior between dye concentration and absorption. The kinetics of the dye was compared to iodinated contrast medium and was found to be in good agreement. The contrast enhancement curves were reliably detected in three mice with individual bolus shapes and delay times of 2.1, 3.5 and 6.1 s, respectively. The optical sensor appears to be a promising approach to optimize injection protocols and contrast enhancement timing and is applicable to all modalities without implying any additional radiation dose. Clinical tests are still necessary. (note)

  15. Comparison of neutral oral contrast versus positive oral contrast medium in abdominal multidetector CT

    International Nuclear Information System (INIS)

    Berther, Ralph; Eckhardt, Boris; Zollikofer, Christoph L.; Patak, Michael A.; Erturk, Sukru M.

    2008-01-01

    To determine whether neutral contrast agents with water-equivalent intraluminal attenuation can improve delineation of the bowel wall and increase overall image quality for a non-selected patient population, a neutral oral contrast agent (3% mannitol) was administered to 100 patients referred for abdominal multidetector row computed tomography (MDCT). Their results were compared with those of 100 patients given a positive oral contrast agent. Qualitative and quantitative measurements were done on different levels of the gastrointestinal tract by three experienced readers. Patients given the neutral oral contrast agent showed significant better qualitative results for bowel distension (P<0.001), homogeneity of the luminal content (P<0.001), delineation of the bowel-wall to the lumen (P<0.001) and to the mesentery (P<0.001) and artifacts (P<0.001), leading to a significant better overall image quality (P<0.001) than patients receiving positive oral contrast medium. The quantitative measurements revealed significant better distension (P<0.001) and wall to lumen delineation (P<0.001) for the patients receiving neutral oral contrast medium. The present results show that the neutral oral contrast agent (mannitol) produced better distension, better homogeneity and better delineation of the bowel wall leading to a higher overall image quality than the positive oral contrast medium in a non-selected patient population. (orig.)

  16. Use of iohexol as a gastrointestinal contrast medium in the dog

    International Nuclear Information System (INIS)

    Agut, A.; Sanchez-Valverde, M.A.; Lasaosa, J.M.; Murciano, J.; Molina, F.

    1993-01-01

    Iohexol was administered orally in five dogs. The dose, gastrointestinal (GI) transit time, appearance of mucosal patterns and side effects were studied. Three different doses (525, 700, 875 mgI/kg) were used in each dog at 1-week intervals. GI transit time was rapid. In each dose, gastric emptying commenced immediately after administration of the contrast medium, and was completed within 30–60 min with doses of 525–700 mgI/kg and 90–120 min with 875 mgI/kg. Large intestinal filling was observed within 60-90 min. In the majority of studies, the mucosal border appeared as a thin homogeneous halo of lucency surrounding the more opaque bowel lumen contents. The contrast intensity was not adequate with the lowest dose. The image quality did not deteriorate along the GI tract. No adverse reactions were found. Iohexol is an alternative GI contrast medium in the dog when contrast media are contraindicated

  17. Craniopharyngiomas - the utility of contrast medium enhancement for MR imaging at 1.5 T

    International Nuclear Information System (INIS)

    Hald, J.K.; Eldevik, O.P.; Brunberg, J.A.; Chandler, W.F.

    1994-01-01

    To evaluate the efficacy of i.v. contrast medium administration in MR imaging at 1.5 T in patients with craniopharyngiomas, MR studies of 10 men and 6 women with pathologically proven craniopharyngiomas were made. The MR images were obtained as 3- to 5-mm-thick coronal (n=13) or axial (n=3) T1-weighted images (T1WI) prior to an following i.v. Gd-DTPA administration. Proton density-(PD) and T2-weighted images (T2WI) were also obtained. Conspicuity of tumor margins, cystic versus solid components, size, location and effect upon adjacent structures were separately characterized in all imaging sequences. In 6 patients contrast medium-enhanced T1WI, PD and T2WI demonstrated cystic tumor components not seen on unenhanced T1WI. There were significant differences (p<0.004) on 2-tailed Student's t-test comparing tumor conspicuity on contrast medium-enhanced T1WI with unenhanced T1WI, PD and T2WI. Optimal tumor delineation on MR imaging of patients with craniopharyngiomas justifies the use of i.v. contrast medium. (orig.)

  18. Contrast-enhanced angiographic cone-beam computed tomography without pre-diluted contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Jo, K.I.; Kim, S.R.; Choi, J.H.; Kim, K.H.; Jeon, P. [Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center, Gangnam-gu, Seoul (Korea, Republic of)

    2015-11-15

    Contrast-enhanced cone-beam computed tomography (CBCT) has been introduced and accepted as a useful technique to evaluate delicate vascular anatomy and neurovascular stents. Current protocol for CBCT requires quantitative dilution of contrast medium to obtain adequate quality images. Here, we introduce simple methods to obtain contrast-enhanced CBCT without quantitative contrast dilution. A simple experiment was performed to estimate the change in flow rate in the internal carotid artery during the procedure. Transcranial doppler (TCD) was used to evaluate the velocity change before and after catheterization and fluid infusion. In addition, 0.3 cm{sup 3}/s (n = 3) and 0.2 cm{sup 3}/s (n = 7) contrast infusions were injected and followed by saline flushes using a 300 mmHg pressure bag to evaluate neurovascular stent and host arteries. Flow velocities changed -15 ± 6.8 % and +17 ± 5.5 % from baseline during catheterization and guiding catheter flushing with a 300 mmHg pressure bag, respectively. Evaluation of the stents and vascular structure was feasible using this technique in all patients. Quality assessment showed that the 0.2 cm{sup 3}/s contrast infusion protocol was better for evaluating the stent and host artery. Contrast-enhanced CBCT can be performed without quantitative contrast dilution. Adequate contrast dilution can be achieved with a small saline flush and normal blood flow. (orig.)

  19. Intravenous contrast medium application in elderly patients - evaluation of Iopentol (Imagopaque trademark 300)

    International Nuclear Information System (INIS)

    Rathsmann, P.; Jacobs, G.F.; Mueller, R.D.

    2004-01-01

    Purpose: We examined the subjective compatibility of elderly patients who received the intravenous contrast medium Iopentol (Imagopaque trademark 300). In addition, objective data were acquired to show possible interactions between contrast media and organ systems in old patients. Methods and materials: A CT scan with intravenous application of contrast media was performed on 132 patients ranging in age from 75 to 96 years. The patients were questioned about their individual sensations. In addition, blood pressure, creatinine and CT-densitometry were acquired as objective date. Results: The patients' individual sensations and clinical data show a very low rate of complications. Mild allergic reactions were noticed in two patients. No severe anaphylactic reactions were encountered. Statistically significant changes in blood pressure before and after administration of the contrast medium were not observed. The serum creatinine concentration was unchanged after application of contrast media. For CT-densitometry, the patients were divided into two groups, one group with patients 75-84 years and the other group with patients 85-96 years of age. CT-densitometry showed no age-related differences. The protocol of contrast administration resulted in excellent opacification of the examined regions, only the liver did not enhance in some cases before the opacification of the portal vein. Conclusion: It is shown that old age alone is no reason to withhold contrast media containing iodine when performing CT. For the evaluation of the liver, however, the peculiarities of old age have to be taken into account and the interval between injection of the contrast medium and beginning of the spiral-CT has to be extended. (orig.)

  20. Human pharmacokinetics of iohexol. A new nonionic contrast medium

    International Nuclear Information System (INIS)

    Olsson, B.; Aulie, A.; Sveen, K.; Andrew, E.

    1983-01-01

    The pharmacokinetics of iohexol, a new nonionic, water-soluble contrast medium, have been determined after intravenous injection in 20 healthy volunteers, at four different dose levels (125-500 mg I/kg). The apparent volume of distribution was 0.27 1/kg, indicating distribution in the extracellular water. The biologic half-life was 121 minutes, comparable with that of other intravascular contrast media. Iohexol was excreted completely unmetabolized in the urine, with a 100% recovery 24 hours after injection. A comparison of iohexol and chromium-51 ( 51 Cr)-EDTA clearances indicates that iohexol is mainly excreted by glomerular filtration. The 51 Cr-EDTA clearance was the same when injected separately and concomitantly with iohexol, indicating that glomerular filtration rate is not affected by iohexol. No dose dependency was observed in the investigated parameters t1/2 alpha, t1/2 beta, Vd, ClT or ClR. Iohexol pharmacokinetics are in correspondence with previously reported data on intravascular contrast media

  1. Effects of use of the lodine contrast medium on gamma camera imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pyo, Sung Jae; Cho, Yun Ho [Dept. of Nuclear Medicine, Inha University hospital, Incheon (Korea, Republic of); Choi, Jae Ho [Dept. of Radiological Technology, Ansan College, Ansan (Korea, Republic of)

    2016-12-15

    Effects of Gamma camera imaging on gamma ray counting rates as a function of use and density of the iodine contrast medium currently in primary use for clinics, and changes in gamma ray counting rates as a function of the contrast medium status upon attenuation correction using a CT absorption coefficientin an SPECT/CT attenuation correction will be considered herein. For experimental materials used 99mTcO4 370 MBq and Pamiray 370 mg, Iomeron 350 mg, Visipaque 320 mg, Bonorex 300 mg of iodine contrast medium. For image acquisition, planar imaging was consecutively filmed for 1, 2, 3, 4, 5 min, respectively, 30 min after administration of 99mTcO4. while 60 views were filmed per frame for 20 min at 55 min for the SPECT/CT imaging. In planar imaging, the gamma ray counting rates as a function of filming time were reduced showing a statistically significant difference when mixed according to the type of contrast medium density rather than when the radioactive isotope 99mTcO4 and the saline solution were mixed. In the tomography for mixing of the radioactive isotope 99mTcO4 and saline solution, the mean counting rate without correction by the CT absorption coefficient is 182±26 counts, while the counting rate with correction by the CT absorption coefficient is 531.3±34 counts. In the tomography for mixing of the radioactive isotope 99mTcO4 and the saline solution with the contrast medium, the mean values before attenuation correction by CT absorption coefficient were 166±29, 158.3±17, 154±36, and 150±33 counts depending on the densities of the contrast medium, while the mean values after attenuation correction were 515±03, 503±10, 496±31, and 488.7±33 counts, showing significant differences in both cases when comparatively evaluated with the imaging for no mixing of the contrast medium. Iodine contrast medium affects the rate of gamma ray. Therefore, You should always be preceded before another test on the day of diagnosis.

  2. Efficacy of high iodine concentration contrast medium with saline pushing in hepatic CT in patients with chronic liver disease. Comparison of high doses-standard contrast medium concentration

    International Nuclear Information System (INIS)

    Matoba, Munetaka; Kondo, Tamaki; Nishikawa, Takahiro; Kuginuki, Yasuaki; Yokota, Hajime; Higashi, Kotaro; Tonami, Hisao

    2006-01-01

    The aim of this study was to compare the enhancement of liver parenchyama with high iodine concentration contrast medium with saline pushing to that with high doses standard iodine concentration in hepatic CT in patients with chronic liver disease. There was no statistically significant difference regarding to the enhancement of liver parenchyama between the 370 mgI/ml of contrast medium with saline pushing and high doses standard iodine concentration contrast medium. (author)

  3. Oral contrast medium in PET/CT: should you or shouldn't you?

    International Nuclear Information System (INIS)

    Groves, Ashley M.; Kayani, Irfan; Dickson, John C.; Townsend, Caroline; Croasdale, Ian; Syed, Rizwan; Nagabushan, Nagesh; Hain, Sharon F.; Ell, Peter J.; Bomanji, Jamshed B.

    2005-01-01

    It has been suggested that the use of computed tomography (CT) positive contrast agents has led to attenuation-induced artefacts on 18 F-fluorodeoxyglucose positron emission tomography ( 18 F-FDG PET/CT) systems. Consequently, centres may withhold the use of such agents. Whilst there is theoretical evidence to support the aforementioned claim, the clinical relevance of the induced artefacts has not been widely established. Moreover, the potential benefits of bowel enhancement on PET/CT have yet to be formally evaluated. We therefore prospectively examined PET/CT studies to assess whether the use of oral contrast medium induces clinically relevant artefacts and whether the use of these agents is diagnostically helpful. Over a 2-month period, 18 F-FDG PET/CT images were prospectively reviewed from 200 patients following Gastrografin administration 2 h prior to examination. Both a radiologist and a nuclear medicine physician reviewed the images for contrast medium-mediated clinically relevant artefacts. Artefacts were sought on the CT attenuation-corrected images and were compared with the appearance on non-attenuated-corrected images. The number of examinations in which the oral contrast aided image interpretation was also noted. There were no oral contrast medium-induced clinically significant artefacts. In 38 of the 200 patients, oral contrast aided image interpretation (owing to differentiation of mass/node from bowel, discrimination of intestinal wall from lumen or definition of the anatomy of a relevant site). In 33 of these 38 patients, the anatomical site of interest was the abdomen/pelvis. The use of oral contrast medium in 18 F-FDG PET studies should not be withheld as it improves image interpretation and does not produce clinically significant artefacts. (orig.)

  4. A method to evaluate the dose increase in CT with iodinated contrast medium

    International Nuclear Information System (INIS)

    Amato, Ernesto; Lizio, Domenico; Settineri, Nicola; Di Pasquale, Andrea; Salamone, Ignazio; Pandolfo, Ignazio

    2010-01-01

    Purpose: The objective of this study is to develop a method to calculate the relative dose increase when a computerized tomography scan (CT) is carried out after administration of iodinated contrast medium, with respect to the same CT scan in absence of contrast medium. Methods: A Monte Carlo simulation in GEANT4 of anthropomorphic neck and abdomen phantoms exposed to a simplified model of CT scanner was set up in order to calculate the increase of dose to thyroid, liver, spleen, kidneys, and pancreas as a function of the quantity of iodine accumulated; a series of experimental measurements of Hounsfield unit (HU) increment for known concentrations of iodinated contrast medium was carried out on a Siemens Sensation 16 CT scanner in order to obtain a relationship between the increment in HU and the relative dose increase in the organs studied. The authors applied such a method to calculate the average dose increase in three patients who underwent standard CT protocols consisting of one native scan in absence of contrast, followed by a contrast-enhanced scan in venous phase. Results: The authors validated their GEANT4 Monte Carlo simulation by comparing the resulting dose increases for iodine solutions in water with the ones presented in literature and with their experimental data obtained through a Roentgen therapy unit. The relative dose increases as a function of the iodine mass fraction accumulated and as a function of the Hounsfield unit increment between the contrast-enhanced scan and the native scan are presented. The data shown for the three patients exhibit an average relative dose increase between 22% for liver and 74% for kidneys; also, spleen (34%), pancreas (28%), and thyroid (48%) show a remarkable average increase. Conclusions: The method developed allows a simple evaluation of the dose increase when iodinated contrast medium is used in CT scans, basing on the increment in Hounsfield units observed on the patients' organs. Since many clinical protocols

  5. A method to evaluate the dose increase in CT with iodinated contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Amato, Ernesto; Lizio, Domenico; Settineri, Nicola; Di Pasquale, Andrea; Salamone, Ignazio; Pandolfo, Ignazio [Department of Radiological Sciences, University of Messina, Messina 98125 (Italy); Department of Physics, University of Messina, Messina 98166 (Italy); University Hospital ' ' G. Martino' ' , Messina 98125 (Italy); Department of Radiological Sciences, University of Messina, Messina 98125 (Italy) and University Hospital ' ' G. Martino' ' , Messina 98125 (Italy)

    2010-08-15

    Purpose: The objective of this study is to develop a method to calculate the relative dose increase when a computerized tomography scan (CT) is carried out after administration of iodinated contrast medium, with respect to the same CT scan in absence of contrast medium. Methods: A Monte Carlo simulation in GEANT4 of anthropomorphic neck and abdomen phantoms exposed to a simplified model of CT scanner was set up in order to calculate the increase of dose to thyroid, liver, spleen, kidneys, and pancreas as a function of the quantity of iodine accumulated; a series of experimental measurements of Hounsfield unit (HU) increment for known concentrations of iodinated contrast medium was carried out on a Siemens Sensation 16 CT scanner in order to obtain a relationship between the increment in HU and the relative dose increase in the organs studied. The authors applied such a method to calculate the average dose increase in three patients who underwent standard CT protocols consisting of one native scan in absence of contrast, followed by a contrast-enhanced scan in venous phase. Results: The authors validated their GEANT4 Monte Carlo simulation by comparing the resulting dose increases for iodine solutions in water with the ones presented in literature and with their experimental data obtained through a Roentgen therapy unit. The relative dose increases as a function of the iodine mass fraction accumulated and as a function of the Hounsfield unit increment between the contrast-enhanced scan and the native scan are presented. The data shown for the three patients exhibit an average relative dose increase between 22% for liver and 74% for kidneys; also, spleen (34%), pancreas (28%), and thyroid (48%) show a remarkable average increase. Conclusions: The method developed allows a simple evaluation of the dose increase when iodinated contrast medium is used in CT scans, basing on the increment in Hounsfield units observed on the patients' organs. Since many clinical

  6. Peripheral blood eosinophilia associated with gastrointestinal administration of iodinated contrast media.

    Science.gov (United States)

    Plavsic, Branko M; Newman, Alan C; Reuther, Warren L; Terry, James A; Drnovsek, Valerie H

    2003-03-01

    This study was designed to assess whether gastrointestinal administration of iodinated contrast media results in peripheral blood eosinophilia. We studied 110 patients in a retrospective review. Diatrizoate meglumine and diatrizoate sodium for abdominal CT were administered to 98 of these patients; 22 of the 98 had also been given the same contrast medium administered by enema. The remaining 12 patients were given diatrizoate sodium for gastrointestinal fluoroscopy. A control group of 65 patients underwent single-contrast barium upper gastrointestinal or enema examinations. WBC and eosinophil counts were determined approximately 24 hr before the examination and every 24 hr thereafter, through the ninth day. Eosinophilia was detected in 17 (15.5%) of 110 patients after gastrointestinal administration of iodinated contrast media. The prevalence of eosinophilia after administration of iodinated contrast media was statistically significantly different compared with that in the control group, in which none of the 65 patients had eosinophilia (p contrast agents and lasted through the sixth day, with a peak on the fifth day. The prevalence of eosinophilia was independent of route of application, dose, or type of iodinated contrast medium. Eosinophilia in all cases was clinically asymptomatic. Eosinophilia that is caused by gastrointestinal administration of iodinated contrast media is a transient, clinically silent phenomenon. It may lead to unnecessary workup for known conditions associated with eosinophilia.

  7. Patient radiation dose during fluoroscopy testes with contrast medium

    International Nuclear Information System (INIS)

    Darsalih, Abir Abdelrady El noor

    2016-09-01

    The purpose of this study was to assess the patient radiation dose received in fluoroscopy examinations during contrast medium. The cumulative air kerma (Ck), kerma area product (KAP) and fluoroscopy time were measured for sixty ( male and female ) patients undergoing five fluoroscopy examinations KAP metre which was installed for the purpose of this study. The mean kerma area product were found to be 2.681, 5.1561, 9.85529. 5.7974 and 13.09 Gy.cm"2 for HSG, A.S and D.S, GI Track and sonogram tests, respectively. The obtained mean cumulative dose was were 6.31, 13.88, 24.61, 22.56 and 32.14 mGy for HSG, A.S, A.S and D.S , GI Track, respectively, the mean fluoroscopy time were. 0.18, 0.51,0.89,1.57 and 1.75 min, for HSG, A.S, A.S, and D.S, G1 Track and sonogram test respectively. Patient dose is mainly dependent on the patient size, procedure, equipment used exposure factor and user experience. As KV and mA were controlled by the AEC and it was found to be well calibrated, possible optimization could be achieved by radiologist by decreasing the exposure time if possible. (Author)

  8. Role of hemolysis in potassium release by iodinated contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, K.; Nakamura, T.; Shimizu, Y. [Department of Radiology, Kyoto City Hospital (Japan)

    1999-09-01

    It has been demonstrated that an iodinated contrast medium (CM) causes release of potassium into blood vessel lumina, resulting in an increase in serum potassium. The purpose of the present study was to assess whether this potassium release is due to hemolysis. Fresh human blood was mixed in vitro with CM at a ratio of 10:2. Potassium release rates were determined, and serum haptoglobin and free hemoglobin were measured after 30 min of exposure to CM. To compare the potassium release curve between CM exposure and true hemolysis induced by distilled water, fresh human blood was also mixed with distilled water. The level of serum haptoglobin decreased due to hemodilution. Changes in haptoglobin were not correlated with potassium release rates. The serum free hemoglobin level did not increase significantly, and there was no correlation between changes in the free hemoglobin level and the rate of potassium release. Hemolysis caused by water occurred instantaneously, whereas potassium release caused by CM was a slow response, which was linearly correlated with exposure time. Potassium release from blood cannot be explained by hemolysis. (orig.) With 4 figs., 4 tabs., 3 refs.

  9. Improve identification of details in double-contrast examination of the stomach by means of a new contrast medium mixture

    International Nuclear Information System (INIS)

    Tenner, R.

    1984-01-01

    In a contrast medium study, 100 patients were employed for a comparison between the contrast medium Mikropaque liquid and a mixture of Mikropaque HD and Mikropaque liquid in double-contrast examination of the stomach. The special feature of this method was that one and the same stomach was examined in each case with both contrast media. The new contrast media mixture with Mikropaque HD represents a step forward; the contrast could be enhanced in 80% of the cases, and the finely contoured relief became visible in two-thirds of the cases, compared with one-third of the examined patients before this method was introduced. (orig.) [de

  10. Clinical experience with a non-ionic contrast medium (ultravist) in left ventriculography

    International Nuclear Information System (INIS)

    Lee, Ghi Jai; Park, Jae Hyung; Soe, Gwy Suk; Hong, Ju Hee; Han, Man Chung

    1988-01-01

    Non-ionic contrast medium, iopromide (Ultravist), was compared with ionic contrast medium, ioxitalamate (Telebrix), for efficacy and safety in 63 patients undergoing left ventriculography. In all patients, adverse symptoms and signs including pain, heat sense, nausea, vomiting, etc., were checked during and shortly after the injection. Blood pressure, heart rate, EKG and left ventricular pressure were also monitored during the study, and CBC, UA, BUN and creatinine were checked before and 24 hours after the study. The cineangiographic films were analysed and compared by 2 radiologists for the quality. Serious adverse effect did not occur in any case. Minor effects, especially nausea, were lee frequently caused by non-ionic contrast medium than by ionic contrast medium, and heat sense to non-ionic contrast medium was less severe than to ionic contrast medium. Except slightly elevated LVEDP at 1,5 minutes after the study in patients given ionic contrast medium, there was no significant change of electrophysiologic parameters and laboratory findings in both groups. In regard to image quality, there was no significant difference between ionic and non-ionic contrast medium. Thus non-ionic contrast medium, iopromide, appears to be safer for use in left ventriculography than the conventional ionic contrast medium, particularly in those patients at high risk of adverse effects.

  11. Magnetic Resonance Imaging in degenerative disease of the lumbar spine: Fat Saturation technique and contrast medium.

    Science.gov (United States)

    D'Aprile, Paola; Nasuto, Michelangelo; Tarantino, Alfredo; Cornacchia, Samantha; Guglielmi, Giuseppe; Jinkins, J Randy

    2018-01-19

    To examine both anterior and posterior elements of the lumbar spine in patients with low back pain using MRI T2-weighted sequences with Fat Saturation (FS) and contrast enhanced T1-weighted sequences with FS. Two thousand eight hundred and twenty (2820) patients (1628 male, 1192 female, mean age 54) presenting low back pain underwent MRI standard examination (Sagittal T1w TSE and T2w TSE, axial T1 SE) with the addition of sagittal and axial T2w Fat Sat (FS) sequences. Among all the patients, 987 (35%) have been studied adding Contrast Enhanced (CE) T1w FS sequences after administration of contrast medium. Among 987 patients studied with contrast medium, we found: active-inflammatory intervertebral osteochondrosis in 646 (65%) patients; degenerative-inflammatory changes in facet joints (facet joint effusion, synovitis, synovial cysts) in 462 (47%); spondylolysis in 69 (7%); degenerative-inflammatory changes of the flava, interspinous and supraspinous ligaments in 245 (25%); inflammatory changes of posterior perispinal muscles in 84 (8%) patients. In patients with suspected no-disc-related low back pain, the implementation of T2w FS and CE T1w FS sequences to the standard MR protocol could allow a better identification of degenerative-inflammatory changes more likely associated to the pain.

  12. Patient safety and adverse events in contrast medium examinations

    International Nuclear Information System (INIS)

    Enge, I.; Edgren, J.

    1989-01-01

    This volume contains six contributions dealing with the properties, safety and economic aspects (lower risks but higher costs of new low-osmonality contrast media compared to the older high-osmonality, ionic ones) of contrast media used in radiology, and risks involved in procedures for administering of radiologic contrast media. (H.W.). refs.; figs.; tabs

  13. Contrast medium enhancement of soft tissues and brain in CT examinations of dogs

    International Nuclear Information System (INIS)

    Pavlicek, M.

    2000-11-01

    CT is an x-ray based method which shows less contrast for soft tissue as has been known from radiography. Therefore, it is necessary to use intravenously administered iodine contrast media to detect and localize tumors, fistulas or other pathologic lesions. Usually contrast medium is administered manually which yields random patterns of media distribution due to varying application pressure during varying administration time, therefore enhancement of parenchymous organs could not be used to the optimum extent. The use of an automatic injection pump guarantees the necessary constancy during the examination procedure to undoubtedly detect pathologic enhancement of organs in the CT-image as known from human medicine. The standards which are expected of the injection pump and the contrast media are: a good contrast enhancement, a good accumulation in the examined organs, an accumulation, which lasts long enough during the diagnostic phase, and a rapid excretion without side effects. Because of the short scan time of the modern CT-scanner, the best contrast enhancement can be administered by a short bolus injection, which can be applied by the automatic injection pump with a defined flow and a defined quantity of contrast media. This guarantees a good enhancement in the chosen region for the duration of the scan. The main aim of this study is to find a standardized flow and quantity of contrast media for defined regions and organs considering the speed of the scanner. In a subsequent step, the existing scan-protocols are then updated using the newly found information. This study showed, that CT examination of the head and brain in middle-sized dogs can be administered with a flow of 0.5 ml/s and a dose of 2 ml of contrast medium per kg weight. The contrast enhancement of the brain is caused by the enhancement of the vessels, the parenchym is free of contrast media - brain shows a low increase of density. Only if the blood-brain-barrier is destroyed, it is possible that

  14. Contrast medium enhancement of soft tissues and brain in CT examinations of dogs

    International Nuclear Information System (INIS)

    Pavlicek, M.

    2000-11-01

    CT is a x-ray based method which shows less contrast for soft tissue as has been known from radiography. Therefore, it is necessary to use intravenously administered iodine contrast media to detect and localize tumors, fistulas or other pathologic lesions. Usually contrast medium is administered manually which yields random patterns of media distribution due to varying application pressure during varying administration time, therefore enhancement of parenchymous organs could not be used to the optimum extent. The use of an automatic injection pump guarantees the necessary constancy during the examination procedure to undoubtedly detect pathologic enhancement of organs in the CT-image as known from human medicine. The standards which are expected of the injection pump and the contrast media are: a good contrast enhancement, a good accumulation in the examined organs, an accumulation, which lasts long enough during the diagnostic phase, and a rapid excretion without side effects. Because of the short scan time of the modern CT-scanner, the best contrast enhancement can be administered by a short bolus injection, which can be applied by the automatic injection pump with a defined flow and a defined quantity of contrast media. This guarantees a good enhancement in the chosen region for the duration of the scan. The main aim of this study is to find a standardized flow and quantity of contrast media for defined regions and organs considering the speed of the scanner. In a subsequent step, the existing scan-protocols are then updated using the newly found information. This study showed, that CT examination of the head and brain in middle-sized dogs can be administered with a flow of 0.5 ml/s and a dose of 2 ml of contrast medium per kg weight. The contrast enhancement of the brain is caused by the enhancement of the vessels, the parenchym is free of contrast media - brain shows a low increase of density. Only if the blood-brain-barrier is destroyed, it is possible that

  15. Training requirements for the administration of intravenous contrast ...

    African Journals Online (AJOL)

    Background. The administration of intravenous contrast media (IVCM) is one of the key areas currently under investigation for inclusion in the South African (SA) radiographers' scope of practice. However, for the radiographers to legally administer IVCM, training guidelines must first be identified, developed and accredited ...

  16. Speckle contrast diffuse correlation tomography of complex turbid medium flow

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Chong; Irwin, Daniel; Lin, Yu; Shang, Yu; He, Lian; Kong, Weikai; Yu, Guoqiang [Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506 (United States); Luo, Jia [Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky 40506 (United States)

    2015-07-15

    Purpose: Developed herein is a three-dimensional (3D) flow contrast imaging system leveraging advancements in the extension of laser speckle contrast imaging theories to deep tissues along with our recently developed finite-element diffuse correlation tomography (DCT) reconstruction scheme. This technique, termed speckle contrast diffuse correlation tomography (scDCT), enables incorporation of complex optical property heterogeneities and sample boundaries. When combined with a reflectance-based design, this system facilitates a rapid segue into flow contrast imaging of larger, in vivo applications such as humans. Methods: A highly sensitive CCD camera was integrated into a reflectance-based optical system. Four long-coherence laser source positions were coupled to an optical switch for sequencing of tomographic data acquisition providing multiple projections through the sample. This system was investigated through incorporation of liquid and solid tissue-like phantoms exhibiting optical properties and flow characteristics typical of human tissues. Computer simulations were also performed for comparisons. A uniquely encountered smear correction algorithm was employed to correct point-source illumination contributions during image capture with the frame-transfer CCD and reflectance setup. Results: Measurements with scDCT on a homogeneous liquid phantom showed that speckle contrast-based deep flow indices were within 12% of those from standard DCT. Inclusion of a solid phantom submerged below the liquid phantom surface allowed for heterogeneity detection and validation. The heterogeneity was identified successfully by reconstructed 3D flow contrast tomography with scDCT. The heterogeneity center and dimensions and averaged relative flow (within 3%) and localization were in agreement with actuality and computer simulations, respectively. Conclusions: A custom cost-effective CCD-based reflectance 3D flow imaging system demonstrated rapid acquisition of dense boundary

  17. Valuation of using saline flush technique of contrast medium on abdominal multidetector row CT scanning

    International Nuclear Information System (INIS)

    Zhao Hong; Wang Ying; He Yanli; Liu Xiaobing; Bao Shiliang; Han Mingjun

    2006-01-01

    Objective: The purpose of this study was to compare the enhancement degree of abdomen organs and vessels after different amount of contrast medium using saline flush in abdomen MDCT scanning, which aimed to not affect contrast enhancement, decreased the amount of contrast medium, and reduced the side-effect. Methods: This study group consisted of 75 patients who were referred for contrast enhanced abdominal MDCT for various reasons. Patients were allocated into three groups: injection of 100ml of contrast medium only (A group), injection of 80ml pushed with 20ml of saline solution (B group), and injection of 70ml pushed with 30ml of saline solution (C group). Attenuation values were measured from the liver, spleen, pancreas, kidney, aorta, portal vein, and inferior vena cava in 33 second and 80 second of imaging after injection contrast medium. Results: The portal venous phases of the spleen, pancreas, kidney, aorta, portal vein had statistically significant difference among groups A, B and C. Post hoc test showed statistically significant difference between A group and C group, But no statistically significant difference during the portal venous phases of the pancreas and the kidney between A group and B group. Conclusion: Using a saline flush technique after the injection contrast medium in abdominal MDCT reduced waste of contrast medium and decrease in nephrotoxicity, at the same time, it would not lose important diagnostic information and saved patients cost for the contrast medium. (authors)

  18. Comparison of renal toxicity after injection of CT contrast medium and MR contrast medium: change of renal function in acute renal failure rat models

    International Nuclear Information System (INIS)

    Han, Young min; Lee, Young Hwan; Kim, Sang Won; Jin, Kong Young; Kim, Won; Chung, Gyung Ho

    2002-01-01

    To determine renal toxicity through changes in renal function after the injection of CT and MRI contrast media into rats in which acute renal failure (ARF) was induced. To cause acute renal failure, the abdominal cavity of 110 male rats each weighing 250-300 gm was opened via a midline incision under anesthesia. Microvascular clamps were placed on both renal arteries and veins to completely block renal blood flow for 45 minutes, and were then removed, allowing blood flow to return to the kidneys. ARF, defined as a two-fold difference in the creatinine level before ARF and 48 hours after, was successfully induced in 60 of the rats. These were divided into two groups: one was injected with CT contrast medium and the other with MRI contrast medium. Each CT and MRI group was divided into a low dose (0.5 cc/kg, 0.2 ml/kg), standard dose (2 cc/kg, 0.8 ml/kg), and high dose (8 cc/kg, 3.2 ml/kg) sub-group; thus, there was a total of six groups with ten rats in each. Blood samples were obtained before ARF, 48 hours after, and 48 hours after contrast injection, and CT scanning and MRI were performed after blood sampling at 48 hours. In each group, creatinine levels 48 hours after contrast injection were compared by means of the ANOVA test. There were no significant differences in creatinine levels between the CT and MRI contrast medium groups (p=0.116), nor between the animals to which different doses of CT and MRI contrast medium, were administered. After both standard and high doses, CT and MRI provided good images. In rats in which acute renal failure was induced, renal function did not change according to whether CT or MRI contrast medium was injected. Thus, the two media induce similar levels of toxicity

  19. Nuclear magnetic resonance diagnosis of cerebral tumours with the use of the contrast medium gadolinium-DTPA

    International Nuclear Information System (INIS)

    Schoerner, W.; Felix, R.; Claussen, C.; Fiegler, W.; Kazner, E.; Speck, U.; Niendorf, H.P.

    1984-01-01

    This study examines the effect of the NMR contrast medium gadolinium-DTPA on image contrast in cerebral tumours. Sixteen patients with space-occupying cerebral lesions were examined on a 0.35 Tesla superconducting scanner, using a T1-weighted spinecho sequence prior to and after the intravenous application of gadolinium-DTPA. In 8 patients T2-weighted spinecho-sequences were obtained before the administration of contrast. The tomograms were evaluated visually and according to quantitative criteria. The use of gadolinium-DTPA helps to evaluate the blood-brain barrier and improves diagnosis by differentiating tumour tissue from edema and from normal brain tissue. (orig.) [de

  20. Synergism of X irradiation and radiographic contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Carr, D; Walker, A; Tannahill, A J; White, R G [Glasgow Western Infirmary (UK)

    1981-10-01

    The results indicate that rabbits which had received abdominal x irradiation (750 rad) two hours before RCM (/sup 125/I-labelled meglumine ioglycamate) administration retained a significantly larger amount of RCM in the kidney, liver, spleen and plasma compared with animals which had received RCM with no prior x irradiation. There was no significant difference between the group receiving RCM alone and the group receiving RCM 24 h post-irradiation. With two insignificant exceptions, endotoxin assays were negative.

  1. Power port contrast medium flushing and trapping: impact of temperature, an in vitro experimental study

    Directory of Open Access Journals (Sweden)

    Guiffant G

    2013-09-01

    Full Text Available Gérard Guiffant,1 Jean Jacques Durussel,1 Patrice Flaud,1 Laurent Royon,1 Pierre Yves Marcy,2 Jacques Merckx1,31University Paris Diderot, Paris, France; 2Radiodiagnosis and Interventional Radiology Department, Caen, France; 3University Teaching Hospital Necker-Enfants Malades, Paris, FrancePurpose: The use of totally implantable venous access devices (TIVADs certified as "high pressure resistant" or "power port" has begun to spread worldwide as a safe procedure for power contrast injection. Owing to the thermo-rheological properties of the contrast media, the primary aim of this work is to present an in vitro experimental impact study concerning the impact of the temperature level on flushing efficiency after contrast medium injection. Moreover, we report experimental data that confirms the role of needle bevel orientation. The secondary aim is to answer the following questions: Is there significant device contrast medium trapping after contrast medium injection? Is saline flushing efficient? And, finally, is it safe to inject contrast medium through an indwelled port catheter?Results: The experimental results show that in addition to hydrodynamics, temperature is a key parameter for the efficiency of device flushing after contrast medium injection. It appears that this is the case when the cavity is incompletely rinsed after three calibrated flushing volumes of 10 mL saline solution, even by using the Huber needle bevel opposite to the port exit. This leads to a potentially important trapped volume of contrast medium in the port, and consequently to the possibility of subsequent salt precipitates and long term trisubstituted benzene nuclei delivery that might impair the solute properties, which may be further injected via the power port later on.Conclusion: We thus suggest, in TIVADS patients, the use of a temporary supplementary intravenous line rather than the port to perform contrast medium injections in daily radiology routine practice

  2. Enhancement effects of test injection with a small amount of MR contrast medium in the oral and maxillofacial region

    International Nuclear Information System (INIS)

    Yanagi, Yoshinobu; Asaumi, Jun-ichi; Konouchi, Hironobu; Hisatomi, Miki; Matsuzaki, Hidenobu; Murakami, Jun; Maki, Yuu; Unetsubo, Teruhisa; Kishi, Kanji

    2006-01-01

    Purpose: To examine whether the signal intensity of dynamic contrast-enhanced MRI (DCE-MRI) is altered by test injection of 1 ml of contrast medium, and if so, whether this change affects the DCE-MRI analysis. Materials and methods: Six healthy volunteers were examined by DCE-MRI using a Magnevist syringe and/or an Omniscan syringe for the injection of contrast medium. Each scan was performed 10 times using steady-state free precession (3D-FISP), a sequence for DCE-MRI, before and after intravenous injection of 1 ml of the contrast medium. The internal pterygoid muscle, masseter muscle, tongue, parotid gland, submandibular gland, bone marrow of the mandible, subcutaneous adipose tissue, and common carotid artery were determined to be regions of interest (ROI), and the ROI internal average signal intensity was measured. The 10 data sets obtained before or after contrast medium administration for each ROI were evaluated using the paired t-test. Results: The test injection increased the signal intensities of six of eight ROIs, with all 20 experiments in the submandibular gland showing significant differences. There was no significant difference in the two ROIs corresponding to the carotid artery and subcutaneous adipose tissue of the cheek. Conclusions: The enhanced signal intensity in the tissue might have been caused by the small amount of contrast medium in the test injection. To eliminate this discrepancy caused by the test injection, a pre-contrast scan should be performed when the average signal intensity of an ROI is measured. We therefore believe that the data obtained before a test injection may be important in the analysis of DCE-MRI

  3. Dual Energy CT Angiography of Peripheral Arterial Disease: Feasibility of Using Lower Contrast Medium Volume.

    Directory of Open Access Journals (Sweden)

    Abdulrahman Almutairi

    Full Text Available One of the main drawbacks associated with Dual Energy Computed Tomography Angiography (DECTA is the risk of developing contrast medium-induced nephropathy (CIN. The aim of the present study was firstly, to design an optimal CT imaging protocol by determining the feasibility of using a reduced contrast medium volume in peripheral arterial DECTA, and secondly, to compare the results with those obtained from using routine contrast medium volume.Thirty four patients underwent DECTA for the diagnosis of peripheral arterial disease. They were randomly divided into two groups: Group 1 (routine contrast volume group with n = 17, injection rate 4-5 ml/s, and 1.5 ml/kg of contrast medium, and Group 2 ((low contrast volume group, with n = 17, injection rate 4-5ml/s, and contrast medium volume 0.75 ml/kg. A fast kilovoltage-switching 64-slice CT scanner in the dual-energy mode was employed for the study. A total of 6 datasets of monochromatic images at 50, 55, 60, 65, 70 and 75 keV levels were reconstructed with adaptive statistical iterative reconstruction (ASIR at 50%. A 4-point scale was the tool for qualitative analysis of results. The two groups were compared and assessed quantitatively for image quality on the basis of signal-to-noise ratio (SNR and contrast-to-noise-ratio (CNR. Radiation and contrast medium doses were also compared.The overall mean CT attenuation and mean noise for all lower extremity body parts was significantly lower for the low volume contrast group (p<0.001, and varied significantly between groups (p = 0.001, body parts (p<0.001 and keVs (p<0.001. The interaction between group body parts was significant with CT attenuation and CNR (p = 0.002 and 0.003 respectively, and marginally significant with SNR (p = 0.047, with minimal changes noticed between the two groups. Group 2 (low contrast volume group displayed the lowest image noise between 65 and 70 keV, recorded the highest SNR and CNR at 65 keV, and produced significantly lower

  4. Renal clearance of an ionic high-osmolar and a nonionic low-osmolar contrast medium

    International Nuclear Information System (INIS)

    Thomsen, H.S.; Vestergaard, A.; Nielsen, S.L.; Fogh-Andersen, N.; Golman, K.; Dorph, S.

    1991-01-01

    One hundred patients with normal serum creatinine concentration underwent intravenous urography with either an ionic high-osmolar (diatrizoate) or a nonionic low-osmolar (iopamidol) contrast medium after randomization. Before injection of the contrast medium, a blood sample was drawn for determinating serum creatinine concentration, and a urine sample for measurement of urine osmolality. Using x-ray fluorescence, the plasma concentration of iodine (contrast medium) was determined on blood samples drawn approximately 3 and 4 hours after injection of the contrast medium. The glomerular filtration rate was calculated by two different formulas: one requiring only a single sample and one requiring at least two samples (standard). There were poor correlations between the standard contrast medium clearance and the serum creatinine concentration, the estimated creatinine clearance (calculated from a nomogram), as well as the urine osmolality. The 3-hour and the 4-hour single-sample values correlated well with the two-sample values for both contrast media. In patients with normal serum creatinine, the glomerular filtration rate determined by measuring the contrast medium concentration in a single plasma sample obtained at 3 hours, is almost identical to the value determined from two samples. Consequently, two samples are unnecessary

  5. Magnetic resonance tomography for focal lesions in the liver using the para-magnetic contrast medium gadolinium DTPA

    International Nuclear Information System (INIS)

    Hamm, B.; Roemer, T.; Felix, R.; Wolf, K.J.; Klinikum Charlottenburg, Berlin

    1986-01-01

    The use of the para-magnetic contrast medium gadolinium DTPA for magnetic resonance tomography of focal lesions in the liver was investigated in 31 patients. Two dosage schedules of the contrast medium (0.1 and 0.2 mmol/kg body weight) were used with field strengths of 0.35 and 0.5 Tesla. Using T 1 sequences, gadolinium DTPA showed increased signal intensity in the liver and in tumours, but this was significantly more marked in the tumour. On T 1 spin-echo sequences, previously iso-intense lesions became visible after administration of contrast. On the other hand, contrast-enhanced lesions were less well seen on inversion recovery sequences because of a reduction in the contrast between tumour and liver tissue. The contrast between tumour and liver tissue was not improved by gadolinium DTPA in comparison with precontrast inversion recovery sequences and T 2 spin-echo sequences. The perfusion of intra-hepatic tumours could be elucidated by magnetic resonance tomography after the administration of gadolinium DTPA. (orig.) [de

  6. The affects of contrast medium on renal function in selective coronary angiography and intervention

    International Nuclear Information System (INIS)

    Chen Yueguang; Lv Baojing

    2006-01-01

    Selective coronary angiography and intervention with injection of contrast medium into the coronary arteries has become very common in dealing with coronary cardiac diseases. The excretion of contrast medium through kidneys may lead to acute renal functional insufficiency, especially for those suffering from chronic nephropathy, diabetes and cardiac functional disorder to form the so called 'contrast medium nephropathy' which is considered as the number second drug induced acute renal functional failure. Although routine preventive measure including low osmotic contrast medium and fine hydrotherapy have been taken, 14% incidences still occur with renal functional damage. The majority could be reversible but the minority needs emergent hemodialysis or even with persistent renal functional damage in a few ones. (authors)

  7. Computed tomography using contrast medium in disorders of the patello-femoral joint

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kenji; Chiba, Mitsuho; Morita, Hiromi; Kikuchi, Toshihiko; Shimada, Yoichi; Yamamoto, Masahiro; Tozawa, Kazuma

    1985-01-01

    The morphology and alignment of the articular cartilage of the patello-femoral joint were examined by computed tomography (CT) using a contrast medium in 15 patients with a chief complaint of patellar pain. CT was undertaken immediately after injecting a contrast medium and air into the knee joint. Retention and irregularity of the contrast medium in the joint estimated the expansion and depth of lesions in patients with osteomalacia of the auricular joint or osteoarthritis of the knee, and the thickness of the auricular cartilage. Considering the individual differences of the patella itself and specificity of the form of the auricular cartilage, the auricular joint should also be examined in terms of alignment of the cartilage surface. CT using a contrast medium is a simple, less invasive method for evaluating disorders of the patello-femoral joint.

  8. Power port contrast medium flushing and trapping: impact of temperature, an in vitro experimental study.

    Science.gov (United States)

    Guiffant, Gérard; Durussel, Jean Jacques; Flaud, Patrice; Royon, Laurent; Marcy, Pierre Yves; Merckx, Jacques

    2013-01-01

    The use of totally implantable venous access devices (TIVADs) certified as "high pressure resistant" or "power port" has begun to spread worldwide as a safe procedure for power contrast injection. Owing to the thermo-rheological properties of the contrast media, the primary aim of this work is to present an in vitro experimental impact study concerning the impact of the temperature level on flushing efficiency after contrast medium injection. Moreover, we report experimental data that confirms the role of needle bevel orientation. The secondary aim is to answer the following questions: Is there significant device contrast medium trapping after contrast medium injection? Is saline flushing efficient? And, finally, is it safe to inject contrast medium through an indwelled port catheter? The experimental results show that in addition to hydrodynamics, temperature is a key parameter for the efficiency of device flushing after contrast medium injection. It appears that this is the case when the cavity is incompletely rinsed after three calibrated flushing volumes of 10 mL saline solution, even by using the Huber needle bevel opposite to the port exit. This leads to a potentially important trapped volume of contrast medium in the port, and consequently to the possibility of subsequent salt precipitates and long term trisubstituted benzene nuclei delivery that might impair the solute properties, which may be further injected via the power port later on. We thus suggest, in TIVADS patients, the use of a temporary supplementary intravenous line rather than the port to perform contrast medium injections in daily radiology routine practice.

  9. Adverse effects in coronary angiography: a comparative study of different temperature contrast medium

    International Nuclear Information System (INIS)

    Zhou Peng; Wang Qiulin; Cai Guocai; Li Lu; Jiang Licheng; Yang Zhen; Huang Xiuping

    2011-01-01

    Objective: To investigate the correlation between different temperature contrast medium and the occurrence of adverse effects, including the chest discomfort, the changes of heart rate, ST segment and T wave, the operating time and the used dosage of contrast medium, in performing coronary angiography. Methods: According to the contrast medium temperature used in coronary angiography, the patients were randomly divided into two groups: room temperature group (n=521) and warm temperature group (n=522). The contrast medium used in warm temperature group was bathed in 37 ℃ water for 60 minutes when the coronary angiography was carried out. The T Wave amplitude changes ≥ 0.01 mv, ST segment depression ≥ 0.05 mv, changes in heart rate ≥ 10 times/min were brought into the positive accounting. The occurrence of adverse effects, such as palpitation, chest distress and pectoralgia, the operative time and the used dosage of contrast medium were recorded. The results were analyzed and compared between the two groups. Results: Statistically significant differences in the changes of heart rate, ST segment deviation, T wave change and operating time existed between the two groups (P<0.05). And the difference in the occurrence of adverse effects between the two groups was also statistically significant (P<0.05). Conclusion: When performing coronary angiography, warming of the contrast medium with water bath is greatly conducive to the prevention of cardiac adverse effects. (authors)

  10. Aspiration of barium contrast medium in an elderly man with disordered swallowing

    OpenAIRE

    Bağcı Ceyhan, B.; Çelikel, T.; Koç, M.; Ahıskalı, R.; Biren, T.; Ataizi Çelikel, Ç.

    1995-01-01

    The aspiration of contrast medium during the investigation of gastrointestinal diseases is a well recognized hazard, particularly in patients with swallowing disorders. A case is reported in which accidental aspiration of contrast barium occurred owing to disordered swallowing in an elderly man. The infiltration on chest x-ray persisted 2 years after barium contrast aspiration. Inflammatory reaction and retractile, granular material observed in lung biopsy specimens suggested barium-induced p...

  11. Recommendation to use iso-osmotic contrast medium in interventional treatment

    International Nuclear Information System (INIS)

    Zhou Bing; Cheng Yongde

    2012-01-01

    With the rapid development of imaging diagnostic and interventional therapeutic techniques, the contrast medium (CM) has been used more and more common in clinical practice, and meanwhile more and more attention has been paid to the CM-related adverse events. Contrast induced nephropathy (CN) is the most common CM-related adverse event, and CM-related neurotoxicity has already attracted the physicians' attention. The osmotic pressure of the iso-osmotic contrast medium (IOCM) is quite the same as that of the plasma, and therefore its safety is higher than that of low-osmotic contrast medium (LOCM), the patient's tolerance to IOCM is better than that to LOCM. For this reason, the use of IOCM should be strongly recommended in interventional procedures, which is of great significance to the reduction of the occurrence of CM-related adverse events. (authors)

  12. Risk of contrast-medium-induced nephropathy in high-risk patients undergoing MDCT--a pooled analysis of two randomized trials

    DEFF Research Database (Denmark)

    Thomsen, Henrik S; Morcos, Sameh K

    2009-01-01

    of the LOCM were also observed in patients with GFR contrast agents in patients with moderate-to-severe renal insufficiency, the risk of significant CIN seems to be low. The IOCM iodixanol caused a higher rate of CIN than the LOCM......The incidence of contrast-medium-induced nephropathy (CIN) following intravenous (IV) CM administration of contrast media to renally impaired patients undergoing multidetector computed tomography (MDCT) is not well characterized. Our objective was to investigate the incidence of CIN in patients...... with glomerular filtration rate (GFR) contrast-enhanced MDCT examinations and to compare the rates of CIN following the IV administration of low-osmolar contrast media (LOCM, iopamidol and iomeprol) and an iso-osmolar contrast medium (IOCM, iodixanol). A total of 301 adult patients...

  13. CT contrasting theory. Effects of the concentration, volume and infusion rate of iodine contrast medium on TDC

    International Nuclear Information System (INIS)

    Yamachi, Jun

    2007-01-01

    This study was performed to evaluate the effects in the title on TDC (time-density curve) using a phantom. CT machine used was Toshiba Aquilion Multi 64, TDC phantom was the product of Nemoto-Kyorindo Co., and the contrast medium was Eisai iomeprol, in syringe-sealed formulations of 300 and 350 mg I/mL. The medium was infused at 1-5 mL/sec in the phantom equivalent to body weight of 78 kg (total water volume=1 min circulation=6,000 mL, 800 mL/heart) to obtain 30 TDCs. Evaluated were the relationships of the infusion rate (mL/sec), volume (mL) or time (sec) with TDC parameters of the detection time of the medium, slope, time to reach the maximum CT value, the maximum CT value, time to keep the CT concentration and its actual concentration. Results revealed that, regardless to the difference of formulations of the contrast medium, TDC with high reproducibility can be obtainable by making the infusion rate of I per unit time and body weight (mgI/sec/kg) constant when the infusion time is made identical for CT of the same diagnostic purpose. (R.T.)

  14. The predictive value of the product of contrast medium volume and urinary albumin/creatinine ratio in contrast-induced acute kidney injury.

    Science.gov (United States)

    Wang, Chunrui; Ma, Shuai; Deng, Bo; Lu, Jianxin; Shen, Wei; Jin, Bo; Shi, Haiming; Ding, Feng

    2017-11-01

    Preexisting renal impairment and the amount of contrast media are the most important risk factors for contrast-induced acute kidney injury (CI-AKI). We aimed to investigate whether the product of contrast medium volume and urinary albumin/creatinine ratio (CMV × UACR) would be a better predictor of CI-AKI in patients undergoing nonemergency coronary interventions. This was a prospective single-center observational study, and 912 consecutive patients who were exposed to contrast media during coronary interventions were investigated prospectively. CI-AKI is defined as a 44.2 μmol/L rise in serum creatinine or a 25% increase, assessed within 48 h after administration of contrast media in the absence of other causes. Fifty patients (5.48%) developed CI-AKI. The urinary albumin/creatinine ratio (UACR) (OR = 1.002, 95% CI = 1.000-1.003, p = .012) and contrast medium volume (CMV) (OR = 1.008, 95% CI = 1.001-1.014, p = .017) were independent risk factors for the development of CI-AKI. The area under the ROC curve of CMV, UACR and CMV × UACR were 0.662 (95% CI = 0.584-0.741, p < .001), 0.761 (95% CI = 0.674-0.847, p < .001) and 0.808 (95% CI = 0.747-0.896, p < .001), respectively. The cutoff value of CMV × UACR to predict CI-AKI was 1186.2, with 80.0% sensitivity and 62.2% specificity. The product of CMV and UACR (CMV × UACR) might be a predictor of CI-AKI in patients undergoing nonemergency coronary interventions, which was superior to CMV or UACR alone.

  15. 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

  16. Contrast enhancement technique in brain 3D-CTA studies. Optimizing the amount of contrast medium according to scan time based on TDC

    International Nuclear Information System (INIS)

    Terasawa, Kazuaki; Hatcho, Atsushi

    2008-01-01

    In three-dimensional CT angiography (3D-CTA), good reproducibility can be obtained by maintaining the maximum CT numbers (HU) at a specified level. However, the correlation between the scan time and the injection time showed that the maximum CT numbers increased and varied due to the additional contrast enhancement effect from recirculation of the injected contrast medium for longer injection times when the dose of iodinated contrast medium per unit time (mgI/s) was maintained at a specified level based on the time-density curve (TDC) of the phantom. The amount of contrast medium employed at our hospital has been optimized based on an iodinated contrast medium dose per unit time providing a contrast enhancement effect of 300 HU in the middle cerebral artery. Using this standard, a TDC phantom was employed to obtain an iodinated contrast medium dose per unit time, permitting equivalent maximum CT values (used as standard values) to be obtained by changing the injection time. A contrast-enhancement technique that accounts for the variation in the scan time was evaluated. Strong correlations were observed between the scan time and the injection time (R 2 =0.969) and between the injection time and the dose of iodinated contrast medium per unit body weight (R 2 =0.994). We conclude that adjusting the dose of iodinated contrast medium per unit body weight per unit time according to the scan time permits optimization of the contrast-enhancement technique. (author)

  17. Pure and diluted contrast medium in the evaluation of portal venous system with digital subtraction angiography

    International Nuclear Information System (INIS)

    Gattoni, F.; Baldini, V.; Pozzato, C.; Nessi, R.; Raiteri, R.; Uscenghi, C.; Opocher, E.; Santambrogio, R.

    1990-01-01

    We report the results of intra-arterial digital subtraction angiography (DSA) in 100 patients with portal hypertension. The portal venous system was evaluated; all patients underwent angiography of the celiac and superior mesenteric arteries before surgery. Forty-four of them were also examined after Warren splenorenal shunts. Therefore, a total of 144 exams was evaluated. The authors always employed low-osmolality ionic and non-ionic contrast media (iodine concentration: 300-350 mg/ml). In 70 cases pure contrast medium was injected (20/25 ml): in the extant 74 cases it was diluted with an equal volume of saline solution (osmolality and iodine concentration reduced by 50%). Intra-arterial DSA always visualized portal venous system, collateral circulation, shunt location and postoperative changes. The mayor advantage of intra-arterial DSA is the smaller amount of contrast medium injected, so that local and systemic side effects are rare. According to our experience, it is best to dilute the contrast medium and inject the same amount as in conventional angiography, at the same rate. Other well-known advantages of intra-arterial DSA are quicker execution, less injury to arteries using smaller caliber catheters, and low cost. The major disadvantage of intra-arterial DSA, as it appeared also in our study, is the field size of the intensifier, which in our case was limited to 6-9 inches. This is an insufficient coverage for the whole portal system to be studied, and some contrast medium injections become therefore necessary. An average of 3 injections were given to each patient. This problem reduces the advantage of less contrast medium per injection. At any rate, even though intra-arterial DSA exhibits this limitation, it can nevertheless yield important information in the pre- and postoperative evaluation of patients with portal hypertension

  18. Lecithine as an adjuvant in resorption of contrast medium in oral cholecystography

    International Nuclear Information System (INIS)

    Lindgren, I.

    1978-01-01

    No or poor filling of the gallbladder was obtained in 21 patients at cholecystography. They were re-examined after 10 days or later with the addition of lecithine to the contrast medium. The filling of the gallbladder, which was without abnormality, was improved in all cases. The mechanism of this effect is discussed. (Auth.)

  19. Digital subtraction angiography and intraarterial contrast medium injection for coronary examinations

    Energy Technology Data Exchange (ETDEWEB)

    Tobio, R; Kallmeyer, C; Castello, J

    1985-01-01

    Digital subtraction angiography (DSA) is an established method of vasography, most extensively used as i.v. DSA. Intraarterial injection, however, applying selective or non-selective contrast medium injection, seems to be at least as important a technique although it has not yet met with corresponding interest. The article explains advantages of the technique for angiographic examinations, in particular of coronary angiography.

  20. Comparison between two positive and one negative oral contrast medium for abdominal CT diagnosis

    International Nuclear Information System (INIS)

    Zwaan, M.; Gmelin, E.

    1989-01-01

    In a prospective randomised study three groups of 30 patients each were subjected to CT of the entire abdomen. The oral intestinal contrast media used were iodine solution (2%), barium suspension (1.5%) and paraffin emulsion (25%). The results were evaluated according to imaging, artifacts, assessability of the intestinal wall, taste and side effects. All three contrast media are suitable for marking the gastrointestinal tract; paraffin shows advantages in the upper part of the tract and is the only medium that enables assessment of the wall, while causing the lowest rate of artifacts. Barium has a high acceptance and the best tolerance of all contrast agents. (orig.) [de

  1. Transient partial amnesia complicating cardiac and peripheral arteriography with nonionic contrast medium

    International Nuclear Information System (INIS)

    Yildiz, A.; Yencilek, E.; Apaydin, F.D.; Duce, M.N.; Oezer, C.; Atalay, A.

    2003-01-01

    The aim of this study was to present a case of disruption of the blood-brain barrier during the coronary and lower extremity angiographies with radiological and clinical findings. This condition was secondary to intraarterial use of a nonionic, monomeric contrast medium. A total of 450 cc contrast media was used. Computed tomography examination showed contrast enhancement of the right occipital and frontoparietal cortical regions, which returned to normal one day after. The patient also fully recovered from the neurological symptoms within 24 h. We discussed the possible mechanism for blood-brain barrier disruption in this case. (orig.)

  2. Transient partial amnesia complicating cardiac and peripheral arteriography with nonionic contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Yildiz, A.; Yencilek, E.; Apaydin, F.D.; Duce, M.N.; Oezer, C. [Dept. of Radiology, Mersin Ueniv. Tip Fakueltesi Sokak Mersin (Turkey); Atalay, A. [Dept. of Cardiology, Mersin Ueniv. Tip Fakueltesi Sokak Mersin (Turkey)

    2003-12-01

    The aim of this study was to present a case of disruption of the blood-brain barrier during the coronary and lower extremity angiographies with radiological and clinical findings. This condition was secondary to intraarterial use of a nonionic, monomeric contrast medium. A total of 450 cc contrast media was used. Computed tomography examination showed contrast enhancement of the right occipital and frontoparietal cortical regions, which returned to normal one day after. The patient also fully recovered from the neurological symptoms within 24 h. We discussed the possible mechanism for blood-brain barrier disruption in this case. (orig.)

  3. Clinical experience with a commercially available negative oral contrast medium in PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Hausegger, K.; Reinprecht, P. [Roentgendiagnostisches Zentralinstitut, LKH Klagenfurt (Austria); Kau, T. [Roentgendiagnostisches Zentral Inst., Klagenfurt (Austria); Igerc, I.; Lind, P. [Abt. fuer Nuklearmedizin und Spezielle Endokrinologie, LKH Klagenfurt (Austria)

    2005-06-01

    Purpose: to evaluate a commercially available negative oral contrast material for PET/CT. Material and methods: in a prospective series of 49 patients, Mukofalk {sup registered}, which is a vegetarian-based substance, was used as a negative oral contrast medium in whole body PET/CT studies. Mukofalk was administered during a time period of 1.5 hours before the examination. Quality of small bowl distension and eventual pathological tracer uptake in the intestine were evaluated. Results: distension of the small bowel was excellent or good in 41 (85%) and poor in 8 (15%) patients. Mild tracer uptake in the small bowel was observed in 5 patients (10.2%) and moderate uptake in another 2 patients (4%). In none of these patients did the F-18 FDG uptake interfere with image interpretation. Conclusion: Mukofalk {sup registered} can be used as a negative oral contrast medium in PET/CT studies. (orig.)

  4. Clinical experience with a commercially available negative oral contrast medium in PET/CT

    International Nuclear Information System (INIS)

    Hausegger, K.; Reinprecht, P.; Kau, T.; Igerc, I.; Lind, P.

    2005-01-01

    Purpose: to evaluate a commercially available negative oral contrast material for PET/CT. Material and methods: in a prospective series of 49 patients, Mukofalk registered , which is a vegetarian-based substance, was used as a negative oral contrast medium in whole body PET/CT studies. Mukofalk was administered during a time period of 1.5 hours before the examination. Quality of small bowl distension and eventual pathological tracer uptake in the intestine were evaluated. Results: distension of the small bowel was excellent or good in 41 (85%) and poor in 8 (15%) patients. Mild tracer uptake in the small bowel was observed in 5 patients (10.2%) and moderate uptake in another 2 patients (4%). In none of these patients did the F-18 FDG uptake interfere with image interpretation. Conclusion: Mukofalk registered can be used as a negative oral contrast medium in PET/CT studies. (orig.)

  5. Effect of barium sulfate contrast medium on rheology and sensory texture attributes in a model food.

    Science.gov (United States)

    Ekberg, O; Bulow, M; Ekman, S; Hall, G; Stading, M; Wendin, K

    2009-03-01

    The swallowing process can be visualized using videoradiography, by mixing food with contrast medium, e.g., barium sulfate (BaSO(4)), making it radiopaque. The sensory properties of foods may be affected by adding this medium. To evaluate if and to what extent sensory and rheological characteristics of mango purée were altered by adding barium sulfate to the food. This study evaluated four food samples based on mango purée, with no or added barium sulfate contrast medium (0%, 12.5%, 25.0%, and 37.5%), by a radiographic method, and measured sensory texture properties and rheological characteristics. The sensory evaluation was performed by an external trained panel using quantitative descriptive analysis. The ease of swallowing the foods was also evaluated. The sensory texture properties of mango purée were significantly affected by the added barium in all evaluated attributes, as was the perception of particles. Moreover, ease of swallowing was significantly higher in the sample without added contrast medium. All samples decreased in extensional viscosity with increasing extension rate, i.e., all samples were tension thinning. Shear viscosity was not as dependent on the concentration of BaSO(4) as extensional viscosity. Addition of barium sulfate to a model food of mango purée has a major impact on perceived sensory texture attributes as well as on rheological parameters.

  6. Radiologic diagnosis of gastro-oesophageal reflux. Comparison of barium and low-density contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Fransson, S.G.; Soekjer, H.; Johansson, K.E.; Tibbling, L.

    It has been proposed that the high density of ordinary barium suspension may complicate the radiologic diagnosis of gastro-oesophageal reflux. For this reason P-contrast was developed (Ferring AB); a contrast medium with the same density as water (1 g/cm/sup 3/). A comparison of P-contrast and barium (Mixobar Ventrikel 400 mg/ml) was performed in 82 patients. All patients were examined with both contrast media and the findings were compared with those at reflux test at manometry, endoscopy and 24-hour pH monitoring. Another 40 patients and 15 symptom-free controls were examined with two different amounts of barium, 100 ml and 200 ml, to study if the radiologic diagnosis of reflux varied with the volume of contrast medium administered. P-contrast was found to have no advantages over barium for the diagnosis of gastro-oesophageal reflux. The outcome of the radiologic examination was not influenced by the different volumes of barium used.

  7. Gadolinium-DTPA as an oral contrast medium for MR tomography of the abdomen

    International Nuclear Information System (INIS)

    Krahe, T.; Doelken, W.; Lackner, K.; Houselog, M.

    1990-01-01

    150 MR examinations of the upper abdomen were carried out after the oral administration of 5 ml/kg body weight of a gadolinium DTPA formulation (1.0 mmol/l, 15 g/l manitol), with reference to the delineation of the pancreas, the liver and intra-abdominal fat. For comparison, 100 MR examinations without oral opacification of the G.I. tract were evaluated. Contrast administration resulted in a signal-intensive demonstration of the G.I tract for all measurement sequences. The intraluminal contrast improved the distinction between normal and abnormal structures, T 1 and T 2 sequences and the demonstration of fat on T 2 -weighted series. T 1 -weighted series showed the best diagnostic results. In 25% there was meteorism and diarrhoea within 24 hours of the administration of the oral contrast. (orig.) [de

  8. Studies on the usefulness of negative contrast medium for CT-fatty emulsion-in diseases of the gastrointestinal tract

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Tsuneo; Kameda, Kyoko; Tanaka, Koji; Nishimura, Shigeru; Higashide, Toshiaki [Osaka Police Hospital (Japan)

    1983-09-01

    Investigation was made on the usefulness of negative contrast medium for CT-fatty emulsion-, which is applicable to the whole area of the gastrointestinal tract, in diagnoses of diseases of the stomach, pancreas, colon and the organs adjacent to the three. After the administration of the drug, CT was performed and the thickness of the walls were measured for the normal upper gastrointestinal tract in 50 patients and for the normal colon in 25. The normal gastric walls did not exceed 5 mm and the walls of the colon measured about 2.1 mm. Gastric tumors were projected at 80.4%. Especially, the drug was useful for the early diagnosis of schirrus. The pancreas was more clearly projected in 88.4% of the patients. The reconstruction method using the present drug was useful for the investigation of the relationship between the two organs, the stomach and the duodenum, and the pancreas. When CT was performed on a patient laying this right side on the bed, invasion of pancreatic cancer and gastric antrum cancer into the circumferntial organs could be diagnosed. The drug was useful for the identification of tumors in the colon and intrapelvic lesions. The medium was also given to four patients with colitis ulcerosa and the obtained findings on the wall features were same as those obtained by barium enema. The present drug was little associated with side effects and is considered to be an excellent negative contrast medium for all the gastrointestinal tracts.

  9. Gadolinium-DTPA (Magnevist) as a contrast medium for arterial DSA

    International Nuclear Information System (INIS)

    Schild, H.H.; Weber, W.; Boeck, E.; Mildenberger, P.; Strunk, H.; Dueber, C.; Grebe, P.; Schadmand-Fischer, S.; Thelen, M.

    1994-01-01

    16 DSA investigations using intra-arterial Gd-DTPA were performed on 12 patients. The contrast medium was administered either as a 0.5 molar gadolinium solution (commercially available) or diluted with distilled water to a 0.2 -0.4 molar gadolinium solution. The injection was made either by pressure injector or by hand. The aortic arch, abdominal aorta and pelvic and lower limb arteries were examined. 14 of the 16 procedures were diagnostically adequate, but compared with iodinated contrast materials, contrast was less marked. There were no cardiovascular, neurological or allergic side effects. Three patients suffered a feeling of heat and one patient had mild pain during the injection. Even large volumes rapidly injected (up to 20 ml/s of the commercially available solution) were well tolerated. DSA with intra-arterial Gd-DTPA seems to be a suitable alternative for vascular imaging if iodine-containing contrast materials are contraindicated. (orig.) [de

  10. Water as a contrast medium: a re-evaluation using the multidetector-row computed tomography.

    Science.gov (United States)

    Makarawo, Tafadzwa P; Negussie, Edsa; Malde, Sachit; Tilak, Jacqueline; Gayagoy, Jennifer; Watson, Jenna; Francis, Faiz; Lincoln, Denis; Jacobs, Michael J

    2013-07-01

    Water as an intraluminal negative contrast medium produces improved image quality with reduced artefact. However, rapid absorption of oral water in the bowel relative to speed and timing of image capturing has limited its clinical application. These findings predate advances in multidetector-row computed tomography (CT). To re-evaluate differences in image quality, we studied image clarity and luminal distention between the same group of patients who received both a pancreas protocol CT (PPCT) that uses oral water and a conventional positive oral contrast scan. We reviewed 66 patients who had previously undergone both a PPCT and an oral contrast abdominal CT. CT images were independently reviewed by two board-certified radiologists who scored degree of hollow viscus distention and visualization of mural detail using a Likert 5-point scale. Results were evaluated by using the Wilcoxon-signed rank test. Student's t test was applied to evaluate the differences in radiation dosage and Spearman's correlational test was used to evaluate interrater correlation between the radiologists. In comparing the mean radiation dosage, there was no statistical difference between the two protocols, and there was good interrater association with ratios of 0.595 and 0.51 achieved for the PPCT and conventional oral scan, respectively. The Wilcoxon signed-rank test showed statistical differences in the stomach (P contrast medium causing better or equal distention in the bowel and better or equal clarity than routine barium contrast. This calls for a need to reconsider the use of water as a contrast medium in clinical practice.

  11. Computed tomography of the cervical spine with iv injection of contrast medium

    International Nuclear Information System (INIS)

    Magnaldi, S.; Pozzi-Mucelli, R.S.; Cova, M.A.; De Morpurgo, P.

    1989-01-01

    Computed Tomography (CT) without contrast medium is largely applied to the study of intervertebral disk pathology in the lumbar spine, but has not been widely accepted in cervical spine, due to technical and anatomical limitations. For these reasons many neuroradiologists still prefer myelography or myelo-CT. CT may yield better results if combined with iv contrast medium injection, which allows a better visualization of disk herniation. This technique is aimed at enhancing the density of the venous plexus which is located close to the intervertebral disk the vertebral bodies and the neural foramina. A better contrast enhancement is thus obtained between the disk and the spinal cord. The authors' experience is based on 61 patients who underwent contrast enhanced CT; in 22 cases myelography and myelo-CT were also performed. The authors describe their technique and the most frequent CT findings of disk hernation: the typical finding includes a focal hypodensity surrounded by a linear blush, due to a posteriorly dislocated epidural vein. The posterior linear blush alone may be present in few cases. Contrast enhanced CT is very useful in the study of disk pathology of the cervical spine, even when compared with myelography and myelo-CT, due the increase in the density of epidural plexus it allows. However, the technique must be very accurate if the same results as those of myelo-CT are to be obtained

  12. Diagnostic capabilities of the contrast medium verografin in liposomes (animal experiments)

    International Nuclear Information System (INIS)

    Rozenberg, O.A.; Khason, K.P.; Aliyakparov, M.T.; Davidenkova, E.F.; Zherbin, E.A.; Akademiya Meditsinskikh Nauk SSSR, Leningrad. Inst. Ehksperimental'noj Meditsiny)

    1985-01-01

    Some examples for the diagnosis of various diseases of liver and spleen after intravenous (cats, dogs) or intraportal (rodents) injection of lecithin-cholesterol liposomes containing the water soluble contrast medium verografin are described. Tumors of 1 mm were found in the spleen of mice with lymphogranulomatosis, hepatomas of 3-5 mm in rats and lesions of 10 mm in cats with turpentine abscesses. The application of liposomes containing radiographic contrast media offers good possibilities for the diagnosis of liver and spleen. (author)

  13. GE-145, a new low-osmolar dimeric radiographic contrast medium

    International Nuclear Information System (INIS)

    Wistrand, Lars-G.; Rogstad, Astri; Hagelin, Gunnar

    2010-01-01

    Background: Contrast-induced nephrotoxicity is a significant risk when using radiographic contrast media clinically, especially in high risk patients. Consequently, there is a need for a new contrast agent with improved clinical safety with regards to nephrotoxicity. Purpose: To evaluate the physicochemical properties as well as the preclinical safety and biodistribution parameters of the newly developed radiographic contrast medium GE-145. Material and Methods: Standard methods for radiographic contrast media were used for evaluation of physicochemical properties. The acute toxicity in rats was studied at 8, 10, and 12.5 gI/kg, the clinical chemistry parameters were determined, and histology of the kidneys was performed. Biodistribution was studied in rats using 123 I-labeled GE-145. Results: GE-145 is more hydrophilic than iodixanol and has a considerably lower osmolality. The viscosity is similar to that of iodixanol and the protein binding is low. The acute toxicity is similar to that of iodixanol and the biodistribution is similar to that of other radiographic contrast media, showing mainly renal excretion. Kidney histology showed a moderate reversible vacuolization, similar to that of iodixanol. Conclusion: GE-145 exhibits similar preclinical properties to other dimeric radiographic contrast media. In addition, the low osmolality enables an iso-osmolar formulation containing a significantly higher concentration of electrolytes than Visipaque

  14. Administration of biliary contrast media in computed tomography

    International Nuclear Information System (INIS)

    Huebener, K.-H.; Treugut, H.

    1981-01-01

    Biliary contrast media have 2 main uses in computed tomography (CT) of the liver and bile ducts: 1. Labelling of extrahepatic bile ducts in order to aid in the identification of the common bile ducts and the papilla of Vater, particularly in cases of complex, mostly postoperative situs. 2. Differentiation between normal and abnormal liver tissue in cases of focal nodular hyperplasia with proliferation of tumorous bile ducts. The applicability of biliary contrast media is rather limited as far as the improvement of spatial resolution by an increase of contrast is concerned, because the attainable enhancement today remains small. The possibility of interpretation of the liver function is likewise insufficient, because the standard deviation of the time-dependent enhancement is too great in the normal collective in order to register deviations reliably. In cases of liver cirrhosis, a rise of density of at least 40-60 Hounsfield Units (HU) would be desirable. (Auth.)

  15. Gadolinium-DTPA and gadodiamide as an alternative contrast medium for CT

    International Nuclear Information System (INIS)

    Engelbrecht, V.; Koch, J.A.; Rassek, M.; Moedder, U.

    1996-01-01

    To evaluate the effect of intravenously applied gadolinium-based contrast medium in computed tomographic (CT) studies. Serial dilutions of iohexol 300, Gd-DTPA and gadodiamide were scanned with CT in a phantom study using water filled tubes. For quantification of X-ray attenuation, the mean Hounsfield units (HU) were calculated from the CT scans. Five patients with contraindications against iodine contrast agents were examined with abdominal or thoracic CT before and after application of 0.2 mmol/kg body weight of a gadolinium-based contrast agent. In these patients attenuation values were obtained in ROI from unenhanced and enhanced CT scans. The phantom study revealed a 38,4% enhancement for Gd-DTPA and a 35.7% enhancement for gadodiamide scaled on the reference measurements with iohexol 300. Thus, 130.2 ml Gd-DTPA or 140.1 ml gadodiamide are needed to achieve the same attenuation as an i.v. injection of 50 ml iohexol 300. Consequently the corresponding dose of 1 mmol/kg body weight would exceed the manufacturer's recommended dose. In four patients with complete thoracic or abdominal CT, i.v. applied gadolinium-based contrast medium (0.2 mmol/kg) yielded no visible advantage. In these patients parenchymal enhancement did not exceed 25%. Dynamic CT of a patient with focal liver lesion revealed an arterial enhancement peak of 75%. Sufficient parenchymal enhancement in CT studies cannot be achieved with the available gadolinium-based contrast mediums. They might be helpful if only short time vascular enhancement is required. (orig.) [de

  16. The Multi-center Evaluation of the Accuracy of the Contrast MEdium INduced Pd/Pa RaTiO in Predicting FFR (MEMENTO-FFR) Study.

    Science.gov (United States)

    Leone, Antonio Maria; Martin-Reyes, Roberto; Baptista, Sergio B; Amabile, Nicolas; Raposo, Luis; Franco Pelaez, Juan Antonio; Trani, Carlo; Cialdella, Pio; Basile, Eloisa; Zimbardo, Giuseppe; Burzotta, Francesco; Porto, Italo; Aurigemma, Cristina; Rebuzzi, Antonio G; Faustino, Mariana; Niccoli, Giampaolo; Abreu, Pedro F; Slama, Michel S; Spagnoli, Vincent; Telleria Arrieta, Miren; Amat Santos, Ignacio J; de la Torre Hernandez, Jose M; Lopez Palop, Ramon; Crea, Filippo

    2016-08-20

    Adenosine administration is needed for the achievement of maximal hyperaemia fractional flow reserve (FFR) assessment. The objective was to test the accuracy of Pd/Pa ratio registered during submaximal hyperaemia induced by non-ionic contrast medium (contrast FFR [cFFR]) in predicting FFR and comparing it to the performance of resting Pd/Pa in a collaborative registry of 926 patients enrolled in 10 hospitals from four European countries (Italy, Spain, France and Portugal). Resting Pd/Pa, cFFR and FFR were measured in 1,026 coronary stenoses functionally evaluated using commercially available pressure wires. cFFR was obtained after intracoronary injection of contrast medium, while FFR was measured after administration of adenosine. Resting Pd/Pa and cFFR were significantly higher than FFR (0.93±0.05 vs. 0.87±0.08 vs. 0.84±0.08, ptime and costs.

  17. Long-term results with a nonionic contrast medium - a clinical experience report

    International Nuclear Information System (INIS)

    Hruby, W.; Stellamor, K.

    1987-01-01

    Between January 1982 and May 1986 more than 50 000 patients were examined radioligically with water-soluble (ionic and nonionic) contrast media at the Department of Radiology Rudolfstiftung, Vienna. 1983 only 2,2% of the contrast agents used were nonionic, in 1985 the share had increased to 53,3%. During this period the rate of drug-related side effects (DRSE) decreased from 6,9% (1983) to 3,3% (1985). From 1983 to 1985 DRSE were observed with 1952 patients after administration of ionic agents, whereas after application of nonionic media adverse reactions occurred in only 6 cases, so that DRSE rates of 6,98% respectively 0,07% resulted for ionic respectively nonionic contrast media. These results are discussed with regard to the physicochemical properties and physiological actions of ionic and nonionic contrast agents. (orig.) [de

  18. Transient angioedema of small bowel secondary to intravenous iodinated contrast medium

    Directory of Open Access Journals (Sweden)

    Kirankumar N Kulkarni

    2014-01-01

    Full Text Available We report the clinical details and imaging findings of a case of transient angioedema of the small bowel following intravenous administration of non-ionic iodinated contrast material in a 17 year old female with no predisposing risk factors. Findings included long segment, symmetric, circumferential, low-density, bowel wall thickening involving the duodenum, jejunum, and most of the ileum on computed tomography scan obtained at 7 min following intravenous contrast material injection. This entity is self-limiting with a favourable clinical outcome and requires no specific treatment but only aggressive clinical monitoring.

  19. Automated contrast medium monitoring system for computed tomography--Intra-institutional audit.

    Science.gov (United States)

    Lauretti, Dario Luca; Neri, Emanuele; Faggioni, Lorenzo; Paolicchi, Fabio; Caramella, Davide; Bartolozzi, Carlo

    2015-12-01

    The aim of this study was to analyze the usage and the data recorded by a RIS-PACS-connected contrast medium (CM) monitoring system (Certegra(®), Bayer Healthcare, Leverkusen, Germany) over 19 months of CT activity. The system used was connected to two dual syringe power injectors (each associated with a 16-row and a high definition 64-row multidetector CT scanner, respectively), allowing to manage contrast medium injection parameters and to send and retrieve CT study-related information via RIS/PACS for any scheduled contrast-enhanced CT examination. The system can handle up to 64 variables and can be accessed via touchscreen by CT operators as well as via a web interface by registered users with three different hierarchy levels. Data related to CM injection parameters (i.e. iodine concentration, volume and flow rate of CM, iodine delivery rate and iodine dose, CM injection pressure, and volume and flow rate of saline), patient weight and height, and type of CT study over a testing period spanning from 1 June 2013 to 10 January 2015 were retrieved from the system. Technical alerts occurred for each injection event (such as system disarm due to technical failure, disarm due to operator's stop, incomplete filling of patient data fields, or excessively high injection pressure), as well as interoperability issues related to data sending and receiving to/from the RIS/PACS were also recorded. During the testing period, the CM monitoring system generated a total of 8609 reports, of which 7629 relative to successful injection events (88.6%). 331 alerts were generated, of which 40 resulted in injection interruption and 291 in CM flow rate limitation due to excessively high injection pressure (>325 psi). Average CM volume and flow rate were 93.73 ± 17.58 mL and 3.53 ± 0.89 mL/s, and contrast injection pressure ranged between 5 and 167 psi. A statistically significant correlation was found between iodine concentration and peak IDR (rs=0.2744, psystems can provide a full

  20. In vitro experiments for the development of a high density (HD) barium sulfate contrast medium

    International Nuclear Information System (INIS)

    Klein, J.

    1986-01-01

    In vitro experiments with the high-density (HD) barium meal Falibaryt HD are described. Several charges of BaSO 4 were tested together with certain additives influencing dispersion, stability of the suspension, flowability, surface tension etc. Particle size spectra were measured by the manufacturer, VEB Fahlberg-List. With a simple PVC test plate containing several grooves simulating small details (areae gastricae) the diagnostic capabilities of the HD contrast medium were evaluated in an in vitro test. The developed barium meal Falibaryt HD is in its physical and chemical parameters comparable with Prontobario-HD, one of the best HD barium meals. (author)

  1. Studies on the consistency of internally taken contrast medium for pancreas CT

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, Kishio; Mimura, Seiichi; Tahara, Seiji; Kitayama, Takuichi; Inamura, Keiji; Mikami, Yasutaka; Hashimoto, Keiji; Hiraki, Yoshio; Aono, Kaname

    1985-02-01

    A problem of Pancreatic CT scanning is the discrimination between the pancreas and the adjacent gastrointestinal tract. Generally we administer a dilution of gastrografin internally to make the discrimination. The degree of dilution has been decided by experience at each hospital. When the consistency of the contrast medium is low in density, an enhancement effect cannot be expected, but when the consistency is high, artifacts appear. We have experimented on the degree of the dilution and CT-No to decide the optimum consistency of gastrografin for the diagnosis of pancreatic disease. Statistical analysis of the results show the optimum dilution of gastrografin to be 1.5%.

  2. A case of pulmonary edema developed after intraarterial injection of iodinated contrast medium

    International Nuclear Information System (INIS)

    Min, Byoung Chol; Chun, Kang Woo; Koh, Jae Hyu; Yoon, Jong Sup

    1982-01-01

    Pulmonary edema is a rare adverse reaction to the iodinated contrast medium. Complaining of huge abdominal mass, a 52 years old female was admitted to the Hangang Sungsim Hospital. On physical examination, the patient appeared to be healthy. She had stable vital signs, i.e. BP: 120/80 mmHg, pulse rate: 80/min.etc. An adult head sized mass was palpated in the left mid and lower abdomen. Otherwise nonspecific. On laboratory studies the positive findings were 8-10 WBC/HPF in urine, 25.6 mg/dl for BUN and PVC in EKG. It was negative for urine protein, serum creatinline and liver function test. We injected 100 ml and 30 ml of Urografin 60 through the abdominal aorta dividing 3 times and major branches of the abdominal aorta, respectively. Immediately after complicating angiography, interstitial pulmonary edema was found, showing blurring of the vascular margins, perivascular haziness and thickening of the interlobular septal lines in the both lower lung fields. The blood pressure was dropped to 80/60 mmHg, but pulse rate was normal. She did not complain of dyspnea, and cyanosis was not developed. The urine volume was normally maintained. She was treated for pulmonary edema, which was completely absorbed after 20 hours. And the blood pressure was also normalized. We have experienced a case of pulmonary edema developed after intraarterial injection of the iodinated contrast medium without underlying cardiac, renal and hepatic problems, and reviewed the literatures on mechanisms of pulmonary edema caused by intravascular injection of the iodinated contrast materials

  3. Intravenous contrast medium application in elderly patients - evaluation of Iopentol (Imagopaque trademark 300); Intravenoese Kontrastmittel-Applikation bei aelteren Patienten - Anwendungsbeobachtung von Iopentol (Imagopaque trademark 300)

    Energy Technology Data Exchange (ETDEWEB)

    Rathsmann, P.; Jacobs, G.F.; Mueller, R.D. [Zentrum fuer Klinische Radiologie, Kliniken Essen-Sued (Germany)

    2004-12-01

    Purpose: We examined the subjective compatibility of elderly patients who received the intravenous contrast medium Iopentol (Imagopaque trademark 300). In addition, objective data were acquired to show possible interactions between contrast media and organ systems in old patients. Methods and materials: A CT scan with intravenous application of contrast media was performed on 132 patients ranging in age from 75 to 96 years. The patients were questioned about their individual sensations. In addition, blood pressure, creatinine and CT-densitometry were acquired as objective date. Results: The patients' individual sensations and clinical data show a very low rate of complications. Mild allergic reactions were noticed in two patients. No severe anaphylactic reactions were encountered. Statistically significant changes in blood pressure before and after administration of the contrast medium were not observed. The serum creatinine concentration was unchanged after application of contrast media. For CT-densitometry, the patients were divided into two groups, one group with patients 75-84 years and the other group with patients 85-96 years of age. CT-densitometry showed no age-related differences. The protocol of contrast administration resulted in excellent opacification of the examined regions, only the liver did not enhance in some cases before the opacification of the portal vein. Conclusion: It is shown that old age alone is no reason to withhold contrast media containing iodine when performing CT. For the evaluation of the liver, however, the peculiarities of old age have to be taken into account and the interval between injection of the contrast medium and beginning of the spiral-CT has to be extended. (orig.)

  4. Analytical optimization of digital subtraction mammography with contrast medium using a commercial unit.

    Science.gov (United States)

    Rosado-Méndez, I; Palma, B A; Brandan, M E

    2008-12-01

    Contrast-medium-enhanced digital mammography (CEDM) is an image subtraction technique which might help unmasking lesions embedded in very dense breasts. Previous works have stated the feasibility of CEDM and the imperative need of radiological optimization. This work presents an extension of a former analytical formalism to predict contrast-to-noise ratio (CNR) in subtracted mammograms. The goal is to optimize radiological parameters available in a clinical mammographic unit (x-ray tube anode/filter combination, voltage, and loading) by maximizing CNR and minimizing total mean glandular dose (D(gT)), simulating the experimental application of an iodine-based contrast medium and the image subtraction under dual-energy nontemporal, and single- or dual-energy temporal modalities. Total breast-entrance air kerma is limited to a fixed 8.76 mGy (1 R, similar to screening studies). Mathematical expressions obtained from the formalism are evaluated using computed mammographic x-ray spectra attenuated by an adipose/glandular breast containing an elongated structure filled with an iodinated solution in various concentrations. A systematic study of contrast, its associated variance, and CNR for different spectral combinations is performed, concluding in the proposal of optimum x-ray spectra. The linearity between contrast in subtracted images and iodine mass thickness is proven, including the determination of iodine visualization limits based on Rose's detection criterion. Finally, total breast-entrance air kerma is distributed between both images in various proportions in order to maximize the figure of merit CNR2/D(gT). Predicted results indicate the advantage of temporal subtraction (either single- or dual-energy modalities) with optimum parameters corresponding to high-voltage, strongly hardened Rh/Rh spectra. For temporal techniques, CNR was found to depend mostly on the energy of the iodinated image, and thus reduction in D(gT) could be achieved if the spectral energy

  5. MO-E-17A-02: Incorporation of Contrast Medium Dynamics in Anthropomorphic Phantoms: The Advent of 5D XCAT Models

    Energy Technology Data Exchange (ETDEWEB)

    Sahbaee, P [NC State University, Raleigh, NC (United States); Samei, E [Duke University Medical Center, Durham, NC (United States); Segars, W [Duke University, Durham, NC (United States)

    2014-06-15

    Purpose: To develop a unique method to incorporate the dynamics of contrast-medium propagation into the anthropomorphic phantom, to generate a five-dimensional (5D) patient model for multimodality imaging studies. Methods: A compartmental model of blood circulation network within the body was embodied into an extended cardiac-torso (4D-XCAT) patient model. To do so, a computational physiologic model of the human cardiovascular system was developed which includes a series of compartments representing heart, vessels, and organs. Patient-specific cardiac output and blood volume were used as inputs influenced by the weight, height, age, and gender of the patient's model. For a given injection protocol and given XCAT model, the contrast-medium transmission within the body was described by a series of mass balance differential equations, the solutions to which provided the contrast enhancement-time curves for each organ; thereby defining the tissue materials including the contrastmedium within the XCAT model. A library of time-dependent organ materials was then defined. Each organ in each voxelized 4D-XCAT phantom was assigned to a corresponding time-varying material to create the 5D-XCAT phantom in which the fifth dimension is blood/contrast-medium within the temporal domain. Results: The model effectively predicts the time-varying concentration behavior of various contrast-medium administration in each organ for different patient models as function of patient size (weight/height) and different injection protocol factors (injection rate and pattern, iodine concentration or volume). The contrast enhanced XCAT patient models was developed based on the concentration of iodine as a function of time after injection. Conclusion: Majority of medical imaging systems take advantage of contrast-medium administration in terms of better image quality, the effect of which was ignored in previous optimization studies. The study enables a comprehensive optimization of contrast

  6. Magnesium sulfate as an oral contrast medium in magnetic resonance imaging of the small intestine.

    Science.gov (United States)

    Shi, Hao; Liu, Cun; Ding, Hong Yu; Li, Chun Wei

    2012-03-01

    To explore the use of magnesium sulfate (MgSO4) as an oral contrast medium (CM) in MRI of the small intestine. By comparing MgSO4 SNRs at different concentrations, we determined that 2.5% MgSO4 is the ideal concentration for small bowel MRI. Twenty volunteers underwent MRI after drinking 2.5% MgSO4. Thirty-one patients with clinical suspicion of small intestinal pathology underwent both MRI and the air-barium contrast examination. The patient's tolerance, side effects and complications were noted. 2.5% MgSO4 can decrease the absorption of water and fully fill the enteric cavity, thereby increasing the contrast between the intestinal wall and lumen and facilitating radiographic examination of the small bowel. The mean diameter of the small intestine was 19.8±1.21 mm in the 20 volunteers consuming 2.5% MgSO4 and 12.7±0.84 mm in the 20 volunteers given water. There was a significant difference (P0.05) in side effects between MgSO4 and water groups. Small intestinal MRI was successfully performed in all 31 patients, who were also examined by the double contrast barium, which gave almost identical diagnoses to MRI in all cases except for 1 patient with small intestinal hemorrhage. MRI with 2.5% MgSO4 can demonstrate intestinal abnormalities. Therefore, 2.5% MgSO4 solution is an ideal oral CM for small bowel MRI. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Utility of gadolinium as a contrast medium in endovascular therapeutic procedures; Utilidad del gadolinio como medio de contraste en procedimientos terapeuticos endovasculares

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, R.; Pardo, M. D.; Gorriz, E.; Gallardo, L. (Hospital de Gran Canaria Dr. Negrin); Carreira, J. M. (Universidad de Santiago de Compostela)

    2001-07-01

    To assess the utility of gadolinium associated with CO{sub 2}, as a contrast medium in angiographic studies related to endovascular therapeutic procedures in patients with suboptimal renal function. Between January 2000 and June 2001, endovascular treatments using CO{sub 2} and gadolinium as contrast medium were performed in 10 patients presenting renal function deterioration (creatinine>1.5 mg/ml). A mean dose of 42 ml of gadolinium was administered. The images acquired in diagnostic and therapeutic studied were satisfactory in every case. There was no evidence of significant increases in the previous urea and creatine levels when measured 24, 48 and 72 hours after the procedure. In combination with CO{sub 2} gadolinium is a useful contrast medium for endovascular therapeutic procedures in patients with suboptimal renal function. (Author) 21 refs.

  8. MDCT urography: retrospective determination of optimal delay time after intravenous contrast administration

    International Nuclear Information System (INIS)

    Meindl, Thomas; Coppenrath, Eva; Kahlil, Rami; Reiser, Maximilian F.; Mueller-Lisse, U.G.; Mueller-Lisse, Ulrike L.

    2006-01-01

    The optimal delay time after intravenous (i.v.) administration of contrast medium (CM) for opacifcation of the upper urinary tract (UUT) for multidetector computed tomography urography (MDCTU) was investigated. UUT opacification was retrospectively evaluated in 36 four-row MDCTU examinations. Single- (n=10) or dual-phase (n=26) MDCTU was performed with at least 5-min delay after i.v. CM. UUT was divided into four sections: intrarenal collecting system (IRCS), proximal, middle and distal ureter. Two independent readers rated UUT opacification: 1, none; 2, partial; 3, complete. Numbers and percentages of scores, and the 5%, 25%, 50%, 75% and 95% percentiles of delay time were calculated for each UUT section. After removing diseased segments, 344 segments were analysed. IRCS, proximal and middle ureter were completely opacified in 94% (81/86), 93% (80/86) and 77% (66/86) of cases, respectively. Median delay time was 15 min for complete opacification. The distal ureter was completely opacified in 37% (32/86) of cases and not opacified in 26% (22/86). Median delay time for complete opacification was 11 min with 25% and 75% percentiles of 10 and 16 min, respectively. At MDCTU, opacification of the IRCS, proximal and middle ureter was hardly sensitive to delay time. Delay times between 10 and 16 min were favourable in the distal ureter. (orig.)

  9. Nanoparticles generated by laser in liquids as contrast medium and radiotherapy intensifiers

    Science.gov (United States)

    Restuccia, Nancy; Torrisi, Lorenzo

    2018-01-01

    The synthesis of Au and Ag nanoparticles (NP) though laser ablation in liquids as a function the laser parameters is presented. Spherical NPs with diameter distribution within 1 and 100 nm were prepared by laser ablation in water. The nanoparticles characterization was performed using optical spectroscopy and electronic microscopy (SEM and TEM) measurements. Studies of the possible use of metallic nanoparticles as intensifier of diagnostics imaging contrast medium and absorbing dose from ionizing radiations in traditional radiotherapy and protontherapy are presented. Examples of in vitro (in tissue equivalent materials) and in vivo (in mice), were conducted thank to simulation programs permitting to evaluate the enhancement of efficiency in imaging and therapy as a function of the NPs concentrations and irradiation conditions.

  10. Nanoparticles generated by laser in liquids as contrast medium and radiotherapy intensifiers

    Directory of Open Access Journals (Sweden)

    Restuccia Nancy

    2018-01-01

    Full Text Available The synthesis of Au and Ag nanoparticles (NP though laser ablation in liquids as a function the laser parameters is presented. Spherical NPs with diameter distribution within 1 and 100 nm were prepared by laser ablation in water. The nanoparticles characterization was performed using optical spectroscopy and electronic microscopy (SEM and TEM measurements. Studies of the possible use of metallic nanoparticles as intensifier of diagnostics imaging contrast medium and absorbing dose from ionizing radiations in traditional radiotherapy and protontherapy are presented. Examples of in vitro (in tissue equivalent materials and in vivo (in mice, were conducted thank to simulation programs permitting to evaluate the enhancement of efficiency in imaging and therapy as a function of the NPs concentrations and irradiation conditions.

  11. Effects of barium sulfate as a contrast medium to enterocutaneous fistulas

    International Nuclear Information System (INIS)

    Pelster, F.W.; Reichelt, S.; Arndt, M.; Eising, E.G.

    1989-01-01

    Fistulation following thoracic and epigastric interventions are conservatively treated, as a rule, because of the high rate of complications expected from reoperation. With properly functioning anastomotic transit, insufficiencies usually undergo spontaneous healing, within four to six weeks. Enterocutaneous fistulae developed in 29 of 271 patients with intrathoracic oesophagastric or oesophagojejunal anastomosis. Syringeal ramification into pleural or abdominal cavities were eliminated by means of an absorbable contrast medium, before barium sulphate was orally administered to all patients. Thoracic fistulae were closed after 21.8 days on average, while 20.3 days was the average period required for closure of epigastric fistulae. Barium sulphate was found to stimulate fistular tissue granulation, so that obliteration of the fistular system occurred much sooner, as compared to conservative treatment. The patient's quality of life can thus be improved, and hospitalisation can be shortened. Neither locally delimited nor systemic complications were observed in any of the cases described. (author)

  12. Iomeprol: results of clinical trials in children with a new nonionic contrast medium

    International Nuclear Information System (INIS)

    Gessel, R. van; Moeller, A.; Schmiedel, E.

    1994-01-01

    A total of 438 patients (1 day - 17 years) were enrolled in open-label phase III studies with Iomeprol in the most important radiologic, urologic, and cardiologic indications. Iomeprol was tested in five concentrations ranging from isotonic solutions of 150 mg iodine/ml up to 400 mg iodine/ml. Half of the patients were younger than 3 years. Apart from the mostly slight sensations of heat, pain, and taste, the following adverse events were observed independently of a causal relationship to the test compound: vomiting (1.8%), rise in blood pressure (1.8%), and restlessness (1.1%). The respective incidence of all other adverse events was below 1%. Iomeprol is a suitable and well-tolerated nonionic contrast medium for use in pediatric examinations. (orig./MG) [de

  13. Renal effects of the non-ionic contrast medium iopentol after intravenous injection in healthy volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Jakobsen, J.A.; Berg, K.J.; Waaler, A.; Andrew, E. (Rikshospitalet, Oslo (Norway). Dept. of Radiology Rikshospitalet, Oslo (Norway). Renal Section Nycomed A/S, Oslo (Norway). Dept. of Clinical Research and Development)

    1990-01-01

    Renal effects of the new non-ionic contrast medium iopentol in increasing doses were assessed and compared with the effects of physiologic saline. Twenty-four healthy male volunteers, allocated to three dose groups, were given iopentol intravenously in doses of 0.3, 0.6, and 1.2 g I/kg body weight, respectively. The highest dose group was also given physiologic saline separately as a control. The diuresis increased in all groups, most in the highest dose group, and with a concomitant fall of urine osmolality and increase in osmolar clearance. A slight decrease of serum osmolality, creatinine and urea occurred at 3 hours due to hemodilution. The glomerular filtration rate was unaffected by iopentol. The urinary excretion of albumin and {beta}{sub 2}-microglobulin was unchanged. However, urinary N-acetyl-{beta}-glucosaminidase and alkaline phosphatase increased significantly, most in the highest dose group. All changes were reversible. (orig.).

  14. Contrast medium at the site of the anastomosis is crucial in detecting anastomotic leakage with CT imaging after colorectal surgery.

    Science.gov (United States)

    Huiberts, Astrid A M; Dijksman, Lea M; Boer, Simone A; Krul, Eveline J T; Peringa, Jan; Donkervoort, Sandra C

    2015-06-01

    The use of computed tomography (CT) to detect anastomotic leakage (AL) is becoming the standard of care. Accurate detection of AL is crucial. The aim of this study was to define CT criteria that are most predictive for AL. From January 2006 to December 2012, all consecutive patients who had undergone CT imaging because of clinical suspicion of anastomotic leakage after colorectal surgery were analysed. All CT scans were re-evaluated by two independent abdominal radiologists blinded for clinical outcome. The images were scored with a set of criteria and a conclusion whether or not AL was present was drawn. Each separate criterion was analysed for its value in predicting AL by uni- and multivariable logistic regression Of 668 patients with colorectal surgery, 108 had undergone CT imaging within 16 days postoperatively. According to our standard of reference, 34 (31%) of the patients had AL. Univariable analysis showed that "fluid near anastomosis" (radiologist 1 (rad 1), p leakage" (rad 1, p leakage was the only independent predictor for AL in multivariable analysis for both radiologists (rad 1, OR 5.43 (95% CI 1.18-25.02); rad 2, OR 8.51 (95% CI 2.21-32.83)). The only independent variable predicting AL is leakage of contrast medium. To improve the accuracy of CT imaging, optimal contrast administration near the anastomosis appears to be crucial.

  15. Clinical cardiovascular experiences with iopamidol: a new non-ionic contrast medium

    International Nuclear Information System (INIS)

    Partridge, J.B.; Robinson, P.J.; Turnbull, C.M.; Stoker, J.B.; Morrison, G.W.; Boyle, R.M.

    1981-01-01

    Iopamidol, a new non-ionic water-soluble contrast medium, has been compared with standard ionic media in a number of cardiovascular applications. It is stable in aqueous solution, is much less viscous and only slightly more osmolar than metrizamide. Compared to sodium meglumine diatrizoate in a series of 40 coronary arteriograms, it produced a consistent and highly significant decrease in the incidence and severity of hypotension and bradycardia following intracoronary injection. In the same group and in 62 children undergoing ventricular or great vessel angiocardiography, a subjective assessment of patient reaction showed that iopamidol was better tolerated than the ionic medium. There was a very strong patient preference for iopamidol in a group of 10 of the adult patients who had also consented to femoral artery injections of both media. Throughout these series there was no detectable difference in arterial image quality between the media. Venous phase opacification during arterioportography was assessed in 11 cases comparing iopamidol with sodium meglumine iothalamate. No significant difference was found. We conclude that iopamidol is clearly preferable to ionic media for routine cardiovascular applications. (author)

  16. Contrast medium-enhanced MRI findings and changes over time in stage I tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Oztoprak, I. [Department of Radiology Cumhuriyet University Faculty of Medicine, 58140 Sivas (Turkey)], E-mail: oztoprak@cumhuriyet.edu.tr; Guemues, C.; Oztoprak, B. [Department of Radiology Cumhuriyet University Faculty of Medicine, 58140 Sivas (Turkey); Engin, A. [Department of Infectious Diseases, Cumhuriyet University Faculty of Medicine, Sivas (Turkey)

    2007-12-15

    Aim: To demonstrate the detailed imaging characteristics of early tuberculous meningitis (TBM) and changes over time on standard gadolinium-enhanced, T1-weighted magnetic resonance imaging (MRI) images. Materials and methods: Contrast-enhanced, T1-weighted, spin-echo MRI images of 26 patients with early TBM were evaluated retrospectively. Meningeal enhancement characteristics were categorized according to distribution and pattern as diffuse, focal, linear, nodular, and mixed. Results: We found that 35% of patients had diffuse meningeal enhancement and 65% of cases had focal meningeal enhancement. There was a predilection for focal meningeal enhancement in basal pial areas, the interpeduncular fossa being the most common. In six patients with diffuse meningeal enhancement admitted to hospital relatively early after the onset of symptoms, the type of meningeal enhancement later changed to the focal form. Conclusion: Reactive diffuse meningeal enhancement occurs in the early period of TBM on contrast medium-enhanced T1-weighted MR images, but later becomes limited to basal areas.

  17. Iopamidol, a new non-ionic X-ray contrast medium

    International Nuclear Information System (INIS)

    Hagen, B.

    1982-01-01

    Iopamidol, a new non-ionic, monomeric contrast medium with low osmolality has been well established in our angiographic routine procedures according to the favourable results obtained in more than 300 controlled trials. The general tolerance (demonstrated by the rate of systemic adverse reactions) of the lower concentrated solution (300 mg iodine/ml is a little bit better than that of the higher concentrated one (370 mg iodine/ml). We could demonstrate a significant difference between the two preparations related to local side effects such as pain and heat sensations. The results of 100 intraindividual double blind studies (only peripheral angiography) specially referred to local side effects showed the high significant decrease of pain and heat sensations after application of Iopamidol compared to the results gained by the ionic Ioxitalamate and Ioglicinate. There was no remarkable difference between Iopamidol and Ioxaglate which is a dimeric but likewise low osmolar substance. The role of osmolality in the generation of side effects is pointed out. In consequence the advantages of using contrast media of reducted osmolality particularly in peripheral angiography must be emphasized. (orig.)

  18. Experimental and clinical studies of non-ionic isoosmolality contrast medium (iohexol 140), 2

    International Nuclear Information System (INIS)

    Tajima, Natsuki

    1986-01-01

    Based upon the results of fundamental investigation by the author, that non-ionic isoosmolality contrast medium, iohexol 140 mgI/ml, has almost no adverse effect on the shape of erythrocyte. Intraarterial digital subtraction angiography (IADSA) was performed with this agent in clinical practice. A total number of 344 injections was performed in 100 cases, and angiographic opacifications, subjective reactions and hemodynamic alterations were analysed. The contrast opacifications were excellent or good except five injections on which angiographies were afflicted by misregistration artifact. As for adverse reactions there were only 14 cases who complained mild heat sensations, whereas no pain was experienced. The intensity of local heat sensation at peripheral arteriographies was statistically milder than that caused by diatrizoate 292 mgI/ml (p < 0.001) and iohexol 300 mgI/ml (p < 0.001). The continuous monitorings of femoral blood pressure and electrocardiogram following 16 cases of thoracic aortography, 17 abdominal aortographies and 80 peripheral arteriographies revealed that iohexol 140 mgI/ml caused significantly less effects on decrease of both systolic and diastolic blood pressure and increase of heart rate. Thus it was concluded that iohexol 140 mgI/ml was well suited for IADSA as it caused no pain, good opacification quality and minimum hemodynamic effects. (author)

  19. Contrast medium-enhanced MRI findings and changes over time in stage I tuberculous meningitis

    International Nuclear Information System (INIS)

    Oztoprak, I.; Guemues, C.; Oztoprak, B.; Engin, A.

    2007-01-01

    Aim: To demonstrate the detailed imaging characteristics of early tuberculous meningitis (TBM) and changes over time on standard gadolinium-enhanced, T1-weighted magnetic resonance imaging (MRI) images. Materials and methods: Contrast-enhanced, T1-weighted, spin-echo MRI images of 26 patients with early TBM were evaluated retrospectively. Meningeal enhancement characteristics were categorized according to distribution and pattern as diffuse, focal, linear, nodular, and mixed. Results: We found that 35% of patients had diffuse meningeal enhancement and 65% of cases had focal meningeal enhancement. There was a predilection for focal meningeal enhancement in basal pial areas, the interpeduncular fossa being the most common. In six patients with diffuse meningeal enhancement admitted to hospital relatively early after the onset of symptoms, the type of meningeal enhancement later changed to the focal form. Conclusion: Reactive diffuse meningeal enhancement occurs in the early period of TBM on contrast medium-enhanced T1-weighted MR images, but later becomes limited to basal areas

  20. Risk of contrast-medium-induced nephropathy in high-risk patients undergoing MDCT - A pooled analysis of two randomized trials

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, Henrik S. [University of Copenhagen, Department of Diagnostic Radiology, Copenhagen University Hospital Herlev, and Department of Diagnostic Sciences, Faculty of Health Sciences, Herlev (Denmark); Morcos, Sameh K. [University of Sheffield, Department of Diagnostic Imaging, Northern General Hospital, Sheffield (United Kingdom)

    2009-04-15

    The incidence of contrast-medium-induced nephropathy (CIN) following intravenous (IV) CM administration of contrast media to renally impaired patients undergoing multidetector computed tomography (MDCT) is not well characterized. Our objective was to investigate the incidence of CIN in patients with glomerular filtration rate (GFR) <60 ml/min undergoing contrast-enhanced MDCT examinations and to compare the rates of CIN following the IV administration of low-osmolar contrast media (LOCM, iopamidol and iomeprol) and an iso-osmolar contrast medium (IOCM, iodixanol). A total of 301 adult patients with moderate-to-severe renal failure received a similar IV contrast dose (40 gI). Serum creatinine (SCr) was measured at screening, baseline and 48-72 {+-} 6 h after the MDCT examination. Primary CIN outcome was an increase in SCr {>=}0.5 mg/dl ({>=}44.2 {mu}mol/l) from baseline. The CIN rates were 2.3% in the total population, 0.6% when GFR >40 ml/min, 4.6% when GFR <40 ml/min and 7.8% in patients with GFR <30 ml/min. The incidence of CIN was significantly higher after iodixanol than after LOCM (seven patients, 4.7% following IOCM, no CIN cases following the LOCM; p = 0.007). Significant differences in favor of the LOCM were also observed in patients with GFR <40 ml/min and GFR <30 ml/min. Following the IV administration of nonionic contrast agents in patients with moderate-to-severe renal insufficiency, the risk of significant CIN seems to be low. The IOCM iodixanol caused a higher rate of CIN than the LOCM iopamidol and iomeprol, especially in high-risk patients. Differences in osmolality between these LOCM and iodixanol do not play a role in the genesis of CIN. (orig.)

  1. [Complications due to contrast agent administration: what has been confirmed in prevention?].

    Science.gov (United States)

    Schönenberger, E; Mühler, M; Dewey, M

    2010-12-01

    Computed tomography (CT) and magnetic resonance imaging (MRI) have been evaluated by internists to be the most important medical innovations. Often, intravenous contrast agent administration is required for answering the clinical questions to CT and MRI. In this review we present an overview of the most common and most important aspects that need to be considered prior to intravenous contrast agent administration. We discuss aspects of renal impairment (contrast-induced nephropathy, nephrogenic systemic fibrosis), allergy-like reactions, hyperthyroidism, and pregnancy and breast-feeding.

  2. Arterial and venous blood pressure and blood flow following femoral angiography with a new non-ionic contrast medium

    International Nuclear Information System (INIS)

    Nyman, U.; Almen, T.

    1978-01-01

    At femoral angiography in dogs the effects of a new non-ionic contrast medium (C29) were compared with those of one non-ionic medium (metrizamide) and one ionic medium (meglumine/sodium diatrizoate) in current use. In the leg subjected to angiography the pressure gradient over the peripheral vessels decreased and the femoral blood flow increased. The changes induced by the ionic medium were significantly greater than those induced by metrizamide and C29, whereas no significant difference between the two non-ionic media was recorded. (Auth.)

  3. Analysis on the entrance surface dose and contrast medium dose at computed tomography and angiography in cardiovascular examination

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Hyun [Dept. of Cardiovascular Center, Yeocheon Jeonnam Hospital, Yeosu (Korea, Republic of); Han, Jae Bok; Choi, Nam Gil; Song, Jong Nam [Dept. of Radiological Science, Dongshin University, Naju (Korea, Republic of)

    2016-12-15

    This study aimed to identify dose reduction measures by retrospectively analyzing the entrance surface dose at computed tomography and angiography in cardiovascular examination and to contribute the patients with renal impairmend and a high probability of side effects to determine the inspection's direction by measuring the contrast usages actually to active actions for the dose by actually measuring the contrast medium dose. The CTDIvol value and air kerma value, which are the entrance surface doses of the two examinations, and the contrast medium dose depending on the number of slides were compared and analyzed. This study was conducted in 21 subjects (11 males; 10 females) who underwent Cardiac Computed Tomographic Angiography (CCTA) and Coronary Angiography (CAG) in this hospital during the period from May 2014 to May 2016. The subject's age was 48-85 years old (mean 65±10 years old), and the weight was 37.6~83.3 kg (mean 63±6 kg). Dose reduction could be expected in the cardiovascular examination using CCTA rather than in the examination using CAG. In terms of contrast medium dose, CAG used a smaller dose than CCTA. In particular, as the number of slides increases at CAG, the contrast medium dose increases. Therefore, in order to reduce the contrast medium dose, the number of slides suitable for the scan range must be selected.

  4. Effect of contrast agent administration on consequences of dosimetry and biology in radiotherapy planning

    International Nuclear Information System (INIS)

    Lo, Ching-Jung; Yang, Pei-Ying; Chao, Tsi-Chian; Tu, Shu-Ju

    2015-01-01

    In the treatment planning of radiation therapy, patients may be administrated with contrast media in CT scanning to assist physicians for accurate delineation of the target or organs. However, contrast media are not used in patients during the treatment delivery. In particular, contrast media contain materials with high atomic numbers and dosimetric variations may occur between scenarios where contrast media are present in treatment planning and absent in treatment delivery. In this study we evaluate the effect of contrast media on the dosimetry and biological consequence. An analytical phantom based on AAPM TG 119 and five sets of CT images from clinical patients are included. Different techniques of treatment planning are considered, including 1-field AP, 2-field AP+PA, 4-field box, 7-field IMRT, and RapidArc. RapidArc is a recent technique of volumetric modulated arc therapy and is used in our study of contrast media in clinical scenarios. The effect of RapidArc on dosimetry and biological consequence for administration of contrast media in radiotherapy is not discussed previously in literature. It is shown that dose difference is reduced as the number of external beams is increased, suggesting RapidArc may be favored to be used in the treatment planning enhanced by contrast media. Linear trend lines are fitted for assessment of percent dose differences in the planning target volume versus concentrations of contrast media between plans where contrast media are present and absent, respectively

  5. Gadolinium DTPA as oral contrast medium for MRT of the pancreas

    International Nuclear Information System (INIS)

    Neumann, K.; Kaminsky, S.; Gogoll, M.; Langer, M.; Felix, R.

    1991-01-01

    52 patients with normal pancreas, pancreatitis and pancreatic tumors were examined by magnetic resonance imaging (Magnetom 0,5 T). Using T 1 -, proton density- and T 2 -weighted spin-echo sequences images were obtained before and after oral administration of Gadolinium-DTPA (Gd-DTPA, 1 mM, 15 g/l Mannit, 5-13 ml/kg). Gd-DTPA resulted in hyperintense labeling of small bowel in all sequences and improved visualization of pancreatic head, body and tail in 15, 14 and 7 of 27 patients with normal pancreas and in 17, 8 and 6 of 25 patients with diseased pancreas. Better delineation of pseudocysts and tumorous gut wall invasion were diagnostically profitable. With regard to motion artifact reduced MRI of the intestine using fast sequences Gd-DTPA may be a suitable oral contrast agent to improve the imaging of the pancreas. (orig.) [de

  6. Quantitative evaluation of contrast-enhanced ultrasound after intravenous administration of a microbubble contrast agent for differentiation of benign and malignant thyroid nodules: assessment of diagnostic accuracy.

    Science.gov (United States)

    Nemec, Ursula; Nemec, Stefan F; Novotny, Clemens; Weber, Michael; Czerny, Christian; Krestan, Christian R

    2012-06-01

    To investigate the diagnostic accuracy, through quantitative analysis, of contrast-enhanced ultrasound (CEUS), using a microbubble contrast agent, in the differentiation of thyroid nodules. This prospective study enrolled 46 patients with solitary, scintigraphically non-functional thyroid nodules. These patients were scheduled for surgery and underwent preoperative CEUS with pulse-inversion harmonic imaging after intravenous microbubble contrast medium administration. Using histology as a standard of reference, time-intensity curves of benign and malignant nodules were compared by means of peak enhancement and wash-out enhancement relative to the baseline intensity using a mixed model ANOVA. ROC analysis was performed to assess the diagnostic accuracy in the differentiation of benign and malignant nodules on CEUS. The complete CEUS data of 42 patients (31/42 [73.8%] benign and 11/42 [26.2%] malignant nodules) revealed a significant difference (P benign and malignant nodules. Furthermore, based on ROC analysis, CEUS demonstrated sensitivity of 76.9%, specificity of 84.8% and accuracy of 82.6%. Quantitative analysis of CEUS using a microbubble contrast agent allows the differentiation of benign and malignant thyroid nodules and may potentially serve, in addition to grey-scale and Doppler ultrasound, as an adjunctive tool in the assessment of patients with thyroid nodules. • Contrast-enhanced ultrasound (CEUS) helps differentiate between benign and malignant thyroid nodules. • Quantitative CEUS analysis yields sensitivity of 76.9% and specificity of 84.8%. • CEUS may be a potentially useful adjunct in assessing thyroid nodules.

  7. High-pitch dual-source CT coronary angiography with low volumes of contrast medium

    International Nuclear Information System (INIS)

    Lembcke, Alexander; Hein, Patrick A.; Knobloch, Gesine; Durmus, Tahir; Hamm, Bernd; Schwenke, Carsten; Huppertz, Alexander

    2014-01-01

    To assess the effect of lower volumes of contrast medium (CM) on image quality in high-pitch dual-source computed tomography coronary angiography (CTCA). One-hundred consecutive patients (body weight 65-85 kg, stable heart rate ≤65 bpm, cardiac index ≥2.5 L/min/m 2 ) referred for CTCA were prospectively enrolled. Patients were randomly assigned to one of five groups of different CM volumes (G 30 , 30 mL; G 40 , 40 mL; G 50 , 50 mL; G 60 , 60 mL; G 70 , 70 mL; flow rate 5 mL/s each, iodine content 370 mg/mL). Attenuation within the proximal and distal coronary artery segments was analysed. Mean attenuation for men and women ranged from 345.0 and 399.1 HU in G 30 to 478.2 and 571.8 HU in G 70 . Mean attenuation values were higher in groups with higher CM volumes (P 30 , G 40 , G 50 , G 60 and G 70 were 89 %, 95 %, 98 %, 98 % and 99 %. CM volume of 30 mL in women and 40 mL in men proved to be sufficient to guarantee attenuation of at least 300 HU. In selected patients high-pitch dual-source CTCA can be performed with CM volumes of 40 mL in men or 30 mL in women. (orig.)

  8. Computed tomography of kidney with diuretics. A method for avoiding artifact due to nonionic contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Hiromura, Tadao; Terae, Satoshi; Takamura, Akio; Mizoe, Junetsu (Obihiro Kosei Hospital, Hokkaido (Japan)); Morita, Yutaka; Irie, Goro

    1989-07-01

    We devised a method for avoiding beam-hardening artifacts, which interfere with enhanced CT images of kidney due to nonionic contrast medium. The radiographic effect and the frequency of beam-hardening artifacts on enhanced CT of kidney were studied by prospective comparison among three groups: a group of 20 patients examined with furosemide (f-d.CT), a group of 20 patients examined without diuretics (non-d.CT) and a group of 20 patients examined after water intake (w-d.CT). In all patients of f-d.CT group, the renal parenchyma from the cortex to the papilla was almost evently enhanced, free from artifacts. The density of the renal papilla and pelvis in non-d.CT and w-d.CT groups was significantly higher than that in f-d.CT group, and artifacts were also observed in 14 (70%) of non-d.CT group and 12 (60%) of w.d.CT group, respectively. Satisfactory CT of kidney free from artifacts was obtained by f-d.CT, providing easy evaluation of renal pelvic or peripelvic lesions. In conclusion, this technique can be used in those pathologic cases of renal pelvis or peripelvic region, that are not clear on routine CT because of artifacts. (author).

  9. Hydration for the prevention of contrast medium-induced nephropathy. An update

    International Nuclear Information System (INIS)

    Heinrich, M.; Uder, M.

    2006-01-01

    Contrast medium-induced nephropathy (CIN) continues to be one of the most common causes of hospital-acquired acute renal failure. Since most of the clinical studies on the prophylactic use of different drugs to prevent CIN produced disappointing results, hydration remains the mainstay of prophylaxis. A number of recent prospective randomized trials provided further evidence of the effectiveness of hydration and relevant information regarding the optimization of hydration protocols. It was shown that a bolus hydration solely during examination is not sufficient to prevent CIN. In addition, isotonic 0.9% saline was superior to the commonly used halfisotonic 0.45% saline in another trial. An outpatient hydration protocol including oral hydration before the examination followed by forced intravenous hydration over 6 hrs. beginning 30 to 60 min. prior to examination seems to be comparable to the usual hydration over 24 hrs. Another hydration protocol, which could also be very attractive especially for outpatients, included the infusion of sodium bicarbonate. In a recent trial, hydration with sodium bicarbonate, given as a bolus for 1 hr. prior to examination followed by an infusion for 6 hrs. after examination, was more effective than hydration with sodium chloride for the prophylaxis of CIN. However, there is still a lack of large-scale, multi-center trials comparing different hydration protocols and investigating their influence on clinically relevant endpoints such as mortality or the need for dialysis. (orig.)

  10. Adverse reactions following administration of contrast media for diagnostic imaging in anaesthetized dogs and cats: a retrospective study.

    Science.gov (United States)

    Scarabelli, Stefania; Cripps, Peter; Rioja, Eva; Alderson, Briony

    2016-09-01

    To evaluate incidences of adverse reaction after the administration of contrast media. Retrospective observational study. Animals included 356 dogs and 58 cats receiving non-ionic iodinated contrast agents, and 425 dogs and 49 cats receiving gadolinium-based contrast agents. Anaesthesia records of dogs and cats receiving intravenous (IV) gadobutrol for magnetic resonance imaging (MRI) or IV iohexol for computed tomography (CT) were reviewed. Changes in pulse rate, respiratory rate and mean arterial pressure at 5 minutes after administration of the contrast medium were evaluated. Changes of 10-20% were considered mild, those of >20% moderate, and reactions that required immediate treatment were considered severe. Associations of sex, age and weight with contrast reaction were investigated using logistic regression. Differences in the incidences of reactions to CT and MRI contrast media were examined with chi-squared tests. A p-value of  0.2). Of dogs receiving iohexol, 64 (18.0%) had mild, 65 (18.3%) had moderate and three (0.8%) had severe reactions. Of dogs receiving gadobutrol, 42 (9.9%) had mild, 87 (20.5%) had moderate and one (0.2%) had a severe reaction. When dogs receiving iohexol were compared with those receiving gadobutrol, the odds ratio of a moderate reaction was 2.0 (95% confidence interval 1.34-3.10; p = 0.001). These estimates did not change substantially after adjustment for age, weight and sex. Severe reactions to iohexol and gadobutrol are rare in dogs and cats; moderate reactions are more likely with iohexol than with gadobutrol. © 2015 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

  11. Cytogenetic effects of cardioangiography on blood lymphocytes in children and in vitro effects of contrast medium and low dose radiation

    International Nuclear Information System (INIS)

    Nikula, E.; Kiviniitty, K.

    1987-01-01

    Structural chromosome aberrations were analysed in the peripheral blood lymphocytes of 15 children, aged 1 to 13 years, before, immediately after, 24 hours after and 6 to 8 months after cardioangiographic examination. Statistically significant increases were only demonstrated in the frequency of gaps and, consequently, in the frequency of aberrant cells immediately after cardioangiography. Most of the chromosome damage clearly disappeared within 24 hours. In addition, whole blood cultures were exposed in vitro to low dose radiation, a contrast medium, and radiation together with the contrast medium. No statistically significant differences could be observed in the chromosome aberration frequencies. It was concluded that the modern radiographic procedure, which uses very low radiation doses and less contrast medium, does not cause a consistent, permanent increase of chromosomal damage in the lymphocytes of children. However, the situation may be different if the child undergoes many radiography examinations or the radiation doses are high. (orig./MG)

  12. Quality of abdominal computed tomography angiography: hand versus mechanical intravenous contrast administration in children

    Energy Technology Data Exchange (ETDEWEB)

    Ayyala, Rama S.; Lee, Edward Y. [Boston Children' s Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Zurakowski, David [Boston Children' s Hospital and Harvard Medical School, Departments of Anesthesiology and Surgery, Boston, MA (United States)

    2015-11-15

    Abdominal CT angiography has been increasingly used for evaluation of various conditions related to abdominal vasculature in the pediatric population. However, no direct comparison has evaluated the quality of abdominal CT angiography in children using hand versus mechanical administration of intravenous (IV) contrast agent. To compare hand versus mechanical administration of IV contrast agent in the quality of abdominal CT angiography in the pediatric population. We retrospectively reviewed the electronic medical record to identify pediatric patients (≤18 years) who had abdominal CT angiography between August 2012 and August 2013. The information obtained includes: (1) type of administration of IV contrast agent (hand [group 1] versus mechanical [group 2]), (2) size (gauge) of IV catheter, (3) amount of contrast agent administered and (4) rate of contrast agent administration (ml/s). Two reviewers independently performed qualitative and quantitative evaluation of abdominal CT angiography image quality. Qualitative evaluation of abdominal CT angiography image quality was performed by visual assessment of the degree of contrast enhancement in the region of interest (ROI) based on a 4-point scale. Quantitative evaluation of each CT angiography examination was performed by measuring the Hounsfield unit (HU) using an ROI within the abdominal aorta at two levels (celiac axis and the inferior mesenteric artery) for each child. Analysis of variance (ANOVA) using the F-test was applied to compare contrast enhancement within the abdominal aorta at two levels (celiac axis and inferior mesenteric artery) between hand administration and mechanical administration of IV contrast methods with adjustment for age. We identified 46 pediatric patients (24 male, 22 female; mean age 7.3 ± 5.5 years; range 5 weeks to 18 years) with abdominal CT angiography performed during the study period. Of these patients, 16 (35%; 1.7 ± 2.2 years; range 5 weeks to 5 years) had hand

  13. Quality of abdominal computed tomography angiography: hand versus mechanical intravenous contrast administration in children

    International Nuclear Information System (INIS)

    Ayyala, Rama S.; Lee, Edward Y.; Zurakowski, David

    2015-01-01

    Abdominal CT angiography has been increasingly used for evaluation of various conditions related to abdominal vasculature in the pediatric population. However, no direct comparison has evaluated the quality of abdominal CT angiography in children using hand versus mechanical administration of intravenous (IV) contrast agent. To compare hand versus mechanical administration of IV contrast agent in the quality of abdominal CT angiography in the pediatric population. We retrospectively reviewed the electronic medical record to identify pediatric patients (≤18 years) who had abdominal CT angiography between August 2012 and August 2013. The information obtained includes: (1) type of administration of IV contrast agent (hand [group 1] versus mechanical [group 2]), (2) size (gauge) of IV catheter, (3) amount of contrast agent administered and (4) rate of contrast agent administration (ml/s). Two reviewers independently performed qualitative and quantitative evaluation of abdominal CT angiography image quality. Qualitative evaluation of abdominal CT angiography image quality was performed by visual assessment of the degree of contrast enhancement in the region of interest (ROI) based on a 4-point scale. Quantitative evaluation of each CT angiography examination was performed by measuring the Hounsfield unit (HU) using an ROI within the abdominal aorta at two levels (celiac axis and the inferior mesenteric artery) for each child. Analysis of variance (ANOVA) using the F-test was applied to compare contrast enhancement within the abdominal aorta at two levels (celiac axis and inferior mesenteric artery) between hand administration and mechanical administration of IV contrast methods with adjustment for age. We identified 46 pediatric patients (24 male, 22 female; mean age 7.3 ± 5.5 years; range 5 weeks to 18 years) with abdominal CT angiography performed during the study period. Of these patients, 16 (35%; 1.7 ± 2.2 years; range 5 weeks to 5 years) had hand

  14. Quality of abdominal computed tomography angiography: hand versus mechanical intravenous contrast administration in children.

    Science.gov (United States)

    Ayyala, Rama S; Zurakowski, David; Lee, Edward Y

    2015-11-01

    Abdominal CT angiography has been increasingly used for evaluation of various conditions related to abdominal vasculature in the pediatric population. However, no direct comparison has evaluated the quality of abdominal CT angiography in children using hand versus mechanical administration of intravenous (IV) contrast agent. To compare hand versus mechanical administration of IV contrast agent in the quality of abdominal CT angiography in the pediatric population. We retrospectively reviewed the electronic medical record to identify pediatric patients (≤18 years) who had abdominal CT angiography between August 2012 and August 2013. The information obtained includes: (1) type of administration of IV contrast agent (hand [group 1] versus mechanical [group 2]), (2) size (gauge) of IV catheter, (3) amount of contrast agent administered and (4) rate of contrast agent administration (ml/s). Two reviewers independently performed qualitative and quantitative evaluation of abdominal CT angiography image quality. Qualitative evaluation of abdominal CT angiography image quality was performed by visual assessment of the degree of contrast enhancement in the region of interest (ROI) based on a 4-point scale. Quantitative evaluation of each CT angiography examination was performed by measuring the Hounsfield unit (HU) using an ROI within the abdominal aorta at two levels (celiac axis and the inferior mesenteric artery) for each child. Analysis of variance (ANOVA) using the F-test was applied to compare contrast enhancement within the abdominal aorta at two levels (celiac axis and inferior mesenteric artery) between hand administration and mechanical administration of IV contrast methods with adjustment for age. We identified 46 pediatric patients (24 male, 22 female; mean age 7.3 ± 5.5 years; range 5 weeks to 18 years) with abdominal CT angiography performed during the study period. Of these patients, 16 (35%; 1.7 ± 2.2 years; range 5 weeks to 5 years) had hand

  15. Whole tissue AC susceptibility after superparamagnetic iron oxide contrast agent administration in a rat model

    International Nuclear Information System (INIS)

    Lazaro, Francisco Jose; Gutierrez, Lucia; Rosa Abadia, Ana; Soledad Romero, Maria; Lopez, Antonio; Jesus Munoz, Maria

    2007-01-01

    A magnetic AC susceptibility characterisation of rat tissues after intravenous administration of superparamagnetic iron oxide (Endorem ( R)), at the same dose as established for Magnetic Resonance Imaging (MRI) contrast enhancement in humans, has been carried out. The measurements reveal the presence of the contrast agent as well as that of physiological ferritin in liver and spleen while no traces have been magnetically detected in heart and kidney. This preliminary work opens suggestive possibilities for future biodistribution studies of any type of magnetic carriers

  16. 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.)

  17. 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.)

  18. High incidence of nephropathy in neurosurgical patients after intra-arterial administration of low-osmolar and iso-osmolar contrast media.

    Science.gov (United States)

    Serafin, Zbigniew; Karolkiewicz, Maciej; Gruszka, Marzena; Strózecki, Pawel; Lasek, Wladyslaw; Odrowaz-Sypniewska, Grazyna; Manitius, Jacek; Beuth, Wojciech

    2011-05-01

    Percutaneous endovascular examinations and interventions require significant amounts of iodinated contrast media (CM) and have been reported to be complicated by an increased incidence of post-contrast nephropathy. To evaluate renal function, the incidence of post-contrast nephropathy, and risk factors after interventional procedures in neurosurgical patients after intra-arterial administration of a low-osmolar contrast medium (LOCM) versus an iso-osmolar contrast medium (IOCM). This single-center, prospective, randomized, double-blinded study included 92 patients in its final analysis (mean age 49.6 ± 12.6 years, 29.3% men, mean eGFR 97.8 ± 26.3 mL/min/1.73 m(2)). LOCM was used in 48 patients (52.2%) and IOCM in 44 patients (47.8%). The patients were given an average of 151.2 ± 52.1 mL of contrast medium intra-arterially. Serum creatinine (SCr), urinary N-acetyl-β-glucosaminidase (NAG) excretion, and creatinine clearance (CCr) were measured at baseline, and on days 1 and 3 after the procedure. Baseline risk factors, renal functional parameters, and average CM doses were not statistically different between the two groups. SCr, NAG, and CCr values did not differ significantly between the LOCM and IOCM groups on days 1 and 3 after CM administration. Nephropathy developed in 21 cases (22.8%): 13 (27.1%) after LOCM use and 8 (18.2%) after IOCM; (P = NS). The only significant risk factors of CIN were the diabetes (P = 0.0466) and atherosclerosis (P = 0.0498). We found a high incidence of nephropathy in neurosurgical patients after intra-arterial CM administration. The renal function values and incidence of nephropathy following LOCM administration were not statistically different from those following IOCM administration.

  19. Visualization of endolymphatic hydrops in meniere's disease after single-dose intravenous gadolinium-based contrast medium. Timing of optimal enhancement

    International Nuclear Information System (INIS)

    Naganawa, Shinji; Yamazaki, Masahiro; Kawai, Hisashi; Bokura, Kiminori; Sone, Michihiko; Nakashima, Tsutomu

    2012-01-01

    Visualization of endolymphatic hydrops (EH) in patients with Meniere's disease (MD) is now possible by heavily T 2 -weighted 3-dimensional fluid-attenuated inversion recovery (h T 2 W-3D-FLAIR) obtained 4 hours after intravenous (IV) administration of single dose gadolinium-based contrast medium (GBCM). Although maximum enhancement has been reported 4 hours after contrast administration in healthy volunteers, the timing of optimal enhancement in patients with MD is not reported. We investigated if that optimal timing is earlier or later than 4 hours. We evaluated 10 consecutive patients with suspected MD whom we randomly divided into 2 groups. We obtained h T 2 W-3D-FLAIR before GBCM administration and 10 min, 3.5 hours, and 4 hours after GBCM administration in Group A and before and 10 min, 4 hours, and 4.5 hours after GBCM administration in Group B. We compared signal intensity ratio (SIR) values of the perilymph and pons between 3.5 and 4 hours in Group A and between 4 and 4.5 hours in Group B and evaluated grades of EH at 3.5 and 4 hours in Group A and at 4 and 4.5 hours in Group B. SIR values did not differ significantly between 3.5 and 4 hours in Group A and between 4 and 4.5 hours in Group B. However, SIR values at 4 hours were significantly higher in Group A than Group B. Grades of EH agreed between 3.5 and 4 hours in Group A and between 4 and 4.5 hours in Group B. The optimal timing of contrast enhancement in patients with suspected MD remains unclear, but evaluation of EH may be possible from 3.5 to 4.5 hours after contrast administration. (author)

  20. Nephropathy after administration of iso-osmolar and low-osmolar contrast media

    DEFF Research Database (Denmark)

    Biondi-Zoccai, Giuseppe; Lotrionte, Marzia; Thomsen, Henrik S

    2014-01-01

    BACKGROUND/OBJECTIVES: Contrast-induced nephropathy (CIN) may be a severe complication to the administration of iodine-based contrast media for diagnostic or interventional procedure using radiation exposure. Whether there is a difference in nephrotoxic potential between the various agents...... is uncertain. We aimed to perform a systematic review and network meta-analysis of randomized trials on iodine-based contrast agents. METHODS: Randomized trials of low-osmolar or iso-osmolar contrast media were searched in CENTRAL, Google Scholar, MEDLINE/PubMed, and Scopus. Risk of CIN was appraised within...... a hierarchical Bayesian model computing absolute rates (AR) and odds ratios (OR) with 95% credibility intervals, and probability of being best (Pbest) for each agent. RESULTS: A total of 42 trials (10048 patients) were included focusing on 7 different iodine-based contrast media. Risk of CIN was similarly low...

  1. Introduction of an individually optimized protocol for the injection of contrast medium for coronary CT angiography

    International Nuclear Information System (INIS)

    Seifarth, Harald; Puesken, Michael; Wienbeck, Susanne; Wessling, Johannes; Maintz, David; Heindel, Walter; Juergens, Kai-Uwe; Kalafut, John F.

    2009-01-01

    The aim of this study was to determine whether individually tailored protocols for the injection of contrast medium (CM) result in higher and more homogeneous vascular attenuation throughout the coronary arteries at coronary CT angiography compared with conventional injection protocols using fixed injection parameters. Of 120 patients included in the study, 80 patients were randomized into two groups. Group 1 received 80 mL of CM at 6 mL/s. For group 2 injection parameters were individually adjusted to patient weight, the duration of CT data acquisition, and attenuation parameters following a test bolus. In the control group (group 3) the volume of CM was adjusted to the duration of CT data acquisition and injected at 5 mL/s. Attenuation was measured in the proximal, middle, and distal right coronary artery (RCA), in the proximal and middle left anterior descending artery (LAD), and in cranial and caudal sections of both ventricles. Patient parameters, scan delay, and scan duration did not differ significantly between the groups. Mean CM volume was 82.5 mL (flow rate 5.1 mL/s) in group 2 and 73.5 mL in group 3. Attenuation in both RCA and LAD was significantly higher for group 2 vs. group 3 (RCA: 414.9(±49.9)-396.1(±52.1) HU vs. 366.0(±64.3)-341.6(±72.5) HU; LAD: 398.9(±48.6)-364.6(±44.6) HU vs. 356.3(±69.5)-323.0(±67.2) HU). For group 1 vs. group 2 only attenuation in the distal RCA differed significantly: 396.1(±52.1) vs. 370.7(±70.5) HU. Individually tailored CM injection protocols yield higher attenuation, especially in the distal segments of the coronary vessels, compared with injection protocols using fixed injection parameters. (orig.)

  2. Hepatic contrast medium enhancement at computed tomography and its correlation with various body size measures

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Anders; Nouhad, Jallo; Cederlund, Kerstin; Aspelin, Peter; Torkel, Brismar B., E-mail: anders.svensson@karolinska.se [Dept. of Clinical Science, Intervention and Technology at Karolinska Inst., Div. of Medical Imaging and Technology, Stockholm (Sweden); (Dept. of Radiology, Karolinska Univ. Hospital, Huddinge, Stockholm (Sweden)); Nyman, Ulf (Dept. of Diagnostic Radiology, Lasarettet Trelleborg, Univ. of Lund, Trelleborg (Sweden)); Bjoerk, Jonas (Competence Centre for Clinical Research, Skaane Univ. Hospital, Lund (Sweden)

    2012-07-15

    Background. When the same dose of iodine is given to all patients when performing abdominal computed tomography (CT) there may be a wide inter-individual variation in contrast medium (CM) enhancement of the liver. Purpose. To evaluate if any of the measures body height (BH), body mass index (BMI), lean body mass (LBM), ideal body weight (IBW), and body surface area (BSA) correlated better than body weight (BW) with hepatic enhancement, and to compare the enhancement when using iodixanol and iomeprol. Material and Methods. One hundred patients referred for standard three-phase CT examination of abdomen were enrolled. Body weight and height were measured at the time of the CT examination. Forty grams of iodine (iodixanol 320 mg I/mL or iomeprol 400 mg I/mL) was injected at a rate of 1.6 g-I/s, followed by a 50 mL saline flush. The late arterial phase was determined by using a semi-automatic smart prep technique with a scan delay of 20 s. The hepatic parenchymal phase started automatically 25 s after the late arterial phase. CM concentration was estimated by placement of regions of interest in aorta (native and late arterial phase) and in liver (native and parenchymal phase). Results. BW (r -0.51 and -0.64), LBM (r = -0.54 and -0.59), and BSA (r -0.54 and -0.65) showed the best correlation coefficients with aortic and hepatic parenchymal enhancement, respectively, without any significant differences between the measures. Comparing iodixanol and iomeprol there was no significant difference in aortic enhancement. The liver enhancement was significantly higher (P < 0.05) using iodixanol than iomeprol. Conclusion. To achieve a consistent hepatic enhancement, CM dose may simply be adjusted to body weight instead of using more complicated calculated parameters based on both weight and height.

  3. Morphometric analysis of stab wounds by MSCT and MRI after the instillation of contrast medium.

    Science.gov (United States)

    Fais, Paolo; Cecchetto, Giovanni; Boscolo-Berto, Rafael; Toniolo, Matteo; Viel, Guido; Miotto, Diego; Montisci, Massimo; Tagliaro, Franco; Giraudo, Chiara

    2016-06-01

    To analyze the morphology and depth of stab wounds experimentally produced on human legs amputated for medical reasons using multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) after the instillation of a single contrast medium solution (CMS). For morphological analysis, MSCT and MRI scans were performed before and after the instillation of CMS into the wound cavity. Depth measurements were performed on the sagittal view only after CMS instillation. Subsequently, each wound was dissected using the layer-by-layer technique and the depth was measured by a ruler. One-way between-groups pairwise analysis of variance (ANOVA) and Bland-Altman plot analysis were used for comparing radiological and anatomical measurements. Unenhanced MSCT images did not identify the wound channels, whereas unenhanced MRI evidenced the wound cavity in 50 % of cases. After the instillation of CMS, both MSCT and MRI depicted the wound channel in all the investigated stabbings, although the morphology of the cavity was irregular and did not resemble the shape of the blade. The radiological measurements of the wounds' depth, after the application of CMS, exhibited a high level of agreement (about 95 % at Bland-Altman plot analysis) with the anatomical measurements at dissection. A similar systematic underestimation, however, has been evidenced for MSCT (average 11.4 %; 95 % CI 7-17) and MRI (average 9.6 %; 95 % CI 6-13) data after the instillation of CMS with respect to wound dissection measurements. MSCT and MRI after the instillation of CMS can be used for depicting the morphometric features of stab wounds, although depth measurements are affected by a slight systematic underestimation compared to layer-by-layer dissection.

  4. High-pitch dual-source CT coronary angiography with low volumes of contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Lembcke, Alexander; Hein, Patrick A.; Knobloch, Gesine; Durmus, Tahir; Hamm, Bernd [Charite - University Medicine Berlin, Department of Radiology, Berlin (Germany); Schwenke, Carsten [SCO:SSiS - Schwenke Consulting, Berlin (Germany); Huppertz, Alexander [Charite - University Medicine Berlin, Department of Radiology, Berlin (Germany); ISI - Imaging Science Institute Charite, Berlin (Germany)

    2014-01-15

    To assess the effect of lower volumes of contrast medium (CM) on image quality in high-pitch dual-source computed tomography coronary angiography (CTCA). One-hundred consecutive patients (body weight 65-85 kg, stable heart rate ≤65 bpm, cardiac index ≥2.5 L/min/m{sup 2}) referred for CTCA were prospectively enrolled. Patients were randomly assigned to one of five groups of different CM volumes (G{sub 30}, 30 mL; G{sub 40}, 40 mL; G{sub 50}, 50 mL; G{sub 60}, 60 mL; G{sub 70}, 70 mL; flow rate 5 mL/s each, iodine content 370 mg/mL). Attenuation within the proximal and distal coronary artery segments was analysed. Mean attenuation for men and women ranged from 345.0 and 399.1 HU in G{sub 30} to 478.2 and 571.8 HU in G{sub 70}. Mean attenuation values were higher in groups with higher CM volumes (P < 0.0001) and higher in women than in men (P < 0.0001). The proportions of segments with attenuation of at least 300 HU in G{sub 30}, G{sub 40}, G{sub 50}, G{sub 60} and G{sub 70} were 89 %, 95 %, 98 %, 98 % and 99 %. CM volume of 30 mL in women and 40 mL in men proved to be sufficient to guarantee attenuation of at least 300 HU. In selected patients high-pitch dual-source CTCA can be performed with CM volumes of 40 mL in men or 30 mL in women. (orig.)

  5. Anaphylactoid reactions to the nonvascular administration of water-soluble iodinated contrast media.

    Science.gov (United States)

    Davis, Peter L

    2015-06-01

    Anaphylactoidlike reactions occur during the nonvascular administration of iodinated contrast media. Many of these reactions have been severe. These reactions have occurred with many procedures, including gastrointestinal imaging, cystography, sialography, and hysterosalpingography. This article reviews reports of these reactions. It also reviews what the literature recommends concerning how to deal with individuals undergoing these procedures who are at a higher risk for anaphylactoidlike reactions.

  6. Study of the safety of a new non-ionic contrast medium, iopromide 370 in patients with chronic renal failure

    International Nuclear Information System (INIS)

    Meyrier, A.; Fernet, M.; Rainfray, M.

    1989-01-01

    Intravenous injection of iodinated contrast media usually induces modifications of renal function. Adverse effects of contrast media on renal function may affect diuresis, blood flow or glomerular filtration rate. These modifications are mainly related to osmolality but also chemotoxicity. This open study showed that after i.v. injection of a bolus of iopromide 370, a new non-ionic contrast medium, there was no untoward effect on renal function in patients with renal insufficiency. This justifies comparative studies in patients with renal impairment including elderly subjects, to confirm the tolerance of this product in high risk groups [fr

  7. Soft-tissue tumor differentiation using 3D power Doppler ultrasonography with echo-contrast medium injection.

    Science.gov (United States)

    Chiou, Hong-Jen; Chou, Yi-Hong; Chen, Wei-Ming; Chen, Winby; Wang, Hsin-Kai; Chang, Cheng-Yen

    2010-12-01

    We aimed to evaluate the ability of 3-dimensional power Doppler ultrasonography to differentiate soft-tissue masses from blood flow and vascularization with contrast medium. Twenty-five patients (mean age, 44.1 years; range, 12-77 years) with a palpable mass were enrolled in this study. Volume data were acquired using linear and convex 3-dimensional probes and contrast medium injected manually by bolus. Data were stored and traced slice by slice for 12 slices. All patients were scanned by the same senior sonologist. The vascular index (VI), flow index (FI), and vascular-flow index (VFI) were automatically calculated after the tumor was completely traced. All tumors were later confirmed by pathology. The study included 8 benign (mean, 36.5 mL; range, 2.4-124 mL) and 17 malignant (mean, 319.4 mL; range, 9.9-1,179.6 mL) tumors. Before contrast medium injection, mean VI, FI and VFI were, respectively, 3.22, 32.26 and 1.07 in benign tumors, and 1.97, 29.33 and 0.67 in malignant tumors. After contrast medium injection, they were, respectively, 20.85, 37.33 and 8.52 in benign tumors, and 40.12, 41.21 and 17.77 in malignant tumors. The mean differences between with and without contrast injection for VI, FI and VFI were, respectively, 17.63, 5.07 and 7.45 in benign tumors, and 38.15, 11.88 and 16.55 in malignant tumors. Tumor volume, VI, FI and VFI were not significantly different between benign and malignant tumors before and after echo-contrast medium injection. However, VI, FI and VFI under self-differentiation (differences between with and without contrast injection) were significantly different between malignant and benign tumors. Three-dimensional power Doppler ultrasound is a valuable tool for differential diagnosis of soft-tissue tumors, especially with the injection of an echo-contrast medium. Copyright © 2010 Elsevier. Published by Elsevier B.V. All rights reserved.

  8. [Protective effect of sodium bicarbonate on radiological contrast medium-induced nephropathy in rats].

    Science.gov (United States)

    Vattimo, Maria deFátima Fernandes; dos Santos, Juliana Guareschi

    2013-06-01

    Radiological iodinated contrasts (IC) agents cause acute kidney injury (AKI). To evaluate the renoprotective effect of sodium bicarbonate (Bic) on renal function (creatinine clearance [Clcr], Jaffé, and Clcr mLmin -1 x100 g-1) and the oxidative profile (peroxide excretion, urinary peroxides, urinary malondialdehyde, FOX-2 expression, and thiobarbituric acid reactive substance [TBARS; nmol/mg Cr]) in rats treated with an IC agent. Adult male Wistar rats weighing 250-300 g were treated once daily for 5 days with one of the following treatments: saline (0.9%, 3 mL.kg-1xday-1 intraperitoneally [i.p.]), IC agent (sodium and meglumine ioxitalamate, 3 mL/kg, i.p.), Bic + Saline (3-mL/kg Bic, i.p., 1 h before and after saline treatment), and Bic + IC (3-ml/kg Bic, i.p., 1 h before and after the IC treatment). The IC agent induced AKI, and the antioxidant renoprotective effect of Bic was confirmed (Clcr/TBARS/urinary peroxide: saline group, 0.59+/- 0.03/0.11 +/-0.02/1.29+/- 0.24; Bic+Saline group, 0.58 +/-0.03/0.13+/- 0.02/1.32+/- 0.64; IC group, 0.22 +/- 0.02/0.19 +/- 0.02/4.77 +/- 0.24; Bic +Clgroup, 0.51+/- 0.04/0.13+/- 0.3/1.80+/- 0.04; p<0.05). The protective effect of Bic in the IC-induced AKI was confirmed; hence, Bic administration may be considered as a therapeutic option for patients undergoing IC-enhanced radiography.

  9. Evaluation of the acute adverse reaction of contrast medium with high and moderate iodine concentration in patients undergoing computed tomography

    International Nuclear Information System (INIS)

    Nagamoto, Masashi; Gomi, Tatsuya; Terada, Hitoshi; Terada, Shigehiko; Kohda, Eiichi

    2006-01-01

    The aim of this prospective study was to evaluate and compare acute adverse reactions between contrast medium containing moderate and high concentrations of iodine in patients undergoing computed tomography (CT). A total of 945 patients undergoing enhanced CT were randomly assigned to receive one of two doses of contrast medium. We then prospectively investigated the incidence of adverse reactions. Iopamidol was used as the contrast medium, with a high concentration of 370 mgI/ml and a moderate concentration of 300 mgI/ml. The frequency of adverse reactions, such as pain at the injection site and heat sensation, were determined. Acute adverse reactions were observed in 2.4% (11/458) of the moderate-concentration group compared to 3.11% (15/482) of the high-concentration group; there was no significant difference in incidence between the two groups. Most adverse reactions were mild, and there was no significant difference in severity. One patient in the high-concentration group was seen to have a moderate adverse reaction. No correlation existed between the incidence of adverse reactions and patient characteristics such as sex, age, weight, flow amount, and flow rate. The incidence of pain was not significantly different between the two groups. In contrast, the incidence of heat sensation was significantly higher in the high-concentration group. The incidence and severity of acute adverse reactions were not significantly different between the two groups, and there were no severe adverse reactions in either group. (author)

  10. Urinary Iodine Clearance following Iodinated Contrast Administration: A Comparison of Euthyroid and Postthyroidectomy Subjects

    Directory of Open Access Journals (Sweden)

    Janice D. Ho

    2014-01-01

    Full Text Available Purpose. To compare iodine clearance following iodinated contrast administration in thyroidectomised thyroid cancer patients and euthyroid individuals. Methods. A convenience population (6 thyroidectomised thyroid cancer patients and 7 euthyroid controls was drawn from patients referred for iodinated contrast-enhanced computed tomography (CT studies. Subjects had sequential urine samples collected up to 6 months (50 samples from the thyroidectomised and 63 samples from the euthyroid groups. t-tests and generalised estimating equations (GEE were used to test for group differences in urinary iodine creatinine ratios. Results. Groups had similar urinary iodine creatinine ratios at baseline, with a large increase 2 weeks following iodinated contrast (P=0.005. Both groups had a return of urinary iodine creatinine ratios to baseline by 4 weeks, with no significant group differences overall or at any time point. Conclusions. Thyroidectomised patients did not have a significantly different urinary iodine clearance than euthyroid individuals following administration of iodinated contrast. Both had a return of urinary iodine creatinine ratios to baseline within 4 weeks.

  11. Effects of high iodine doses given parenterally as contrast medium on parameter of the pro/antioxidative balance

    International Nuclear Information System (INIS)

    Winkler, R.; Griebenow, S.; Scheidleder, B.; Bailer, H.

    2002-01-01

    The aim of this study was to investigate effects of high iodine doses given parenterally as contrast medium on parameters of lipid status and thyroid hormone status as well as on parameters of the pro/antioxidative balance of spa patients. 29 patients with a comparable indication who had to undergo an angiography were chosen. The blood parameters of these patients were determined before and after the angiographic treatment. No provable changes of the thyroid parameters f-T 3 , f-T 4 and TSH were found after the angiography. In case of enzyme activities, the protective enzymes SOD and GSHPX showed no changes, while the concentrations of peroxides and MDA were increased significantly. Corresponding to this, the total antioxidative status and the vitamin E level decreased significantly. Altogether these results stand for a moderate deterioration of the antioxidative protective potential by the highly iodine containing contrast medium. (author)

  12. Case with high cervical intramedullary hemangioblastoma associated with arteriovenous fistula. CT with simultaneous intravenous and intrathecal injection of contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Takao; Shoji, Shin-ichi; Yanagisawa, Nobuo; Tada, Tsuyoshi; Kobayashi, Naoki

    1988-02-01

    A 34-year-old woman complained of right hemiparesis and pain in the right hand. Routine X-ray of the cervical portion failed to reveal abnormal findings. CT with intravenous contrast medium showed a large high-density mass in the spinal canal at the level of C2. Right vertebral angiography showed a hypervascular mass. With simultaneous intravenous and intrathecal injections of contrast medium, the tumor was shown as a moderately high-density area and the parenchyma of cord as a thin low-density area surrounding the tumor stain on CT. These CT appearances led to the final diagnosis of high cervical intramedullary hemangioblastoma associated with arteriovenous fistulae. Pathological findings are typical of hemangioblastoma. The usefulness of CT in detecting the localization of hypervascular spinal cord lesions is stressed. (Namekawa, K.).

  13. Estimation of shear velocity contrast for dipping or anisotropic medium from transmitted Ps amplitude variation with ray-parameter

    Science.gov (United States)

    Kumar, Prakash

    2015-12-01

    Amplitude versus offset analysis of P to P reflection is often used in exploration seismology for hydrocarbon exploration. In the present work, the feasibility to estimate crustal velocity structure from transmitted P to S wave amplitude variation with ray-parameter has been investigated separately for dipping layer and anisotropy medium. First, for horizontal and isotropic medium, the approximation of P-to-s conversion is used that is expressed as a linear form in terms of slowness. Next, the intercept of the linear regression has been used to estimate the shear wave velocity contrast (δβ) across an interface. The formulation holds good for isotropic and horizontal layer medium. Application of such formula to anisotropic medium or dipping layer data may lead to erroneous estimation of δβ. In order to overcome this problem, a method has been proposed to compensate the SV-amplitude using shifted version of SH-amplitude, and subsequently transforming SV amplitudes equivalent to that from isotropic or horizontal layer medium as the case may be. Once this transformation has been done, δβ can be estimated using isotropic horizontal layer formula. The shifts required in SH for the compensation are π/2 and π/4 for dipping layer and anisotropic medium, respectively. The effectiveness of the approach has been reported using various synthetic data sets. The methodology is also tested on real data from HI-CLIMB network in Himalaya, where the presence of dipping Moho has already been reported. The result reveals that the average shear wave velocity contrast across the Moho is larger towards the Indian side compared to the higher Himalayan and Tibetan regions.

  14. Transient global amnesia following cerebral angiography with non-ionic contrast medium

    International Nuclear Information System (INIS)

    Schamschula, R.G.; Soo, M.Y.S.

    1994-01-01

    Transit global amnesia (TGA) is an uncommon syndrome of recent memory deficit and inability to learn new data, usually resolving within 24 hours. Two cases following use of non-ionic contrast media in cerebral angiography are presented. The neuroanatomy of memory is reviewed. Possible aetiologies of TGA in relation to cerebral angiography include ischemia (embolic, arterial spasm), epilepsy that may be primary or tumour-related and direct toxic effects of contrast media. 19 refs., 1 fig

  15. Abdominal multi-detector row CT: Effectiveness of determining contrast medium dose on basis of body surface area

    International Nuclear Information System (INIS)

    Onishi, Hiromitsu; Murakami, Takamichi; Kim, Tonsok; Hori, Masatoshi; Osuga, Keigo; Tatsumi, Mitsuaki; Higashihara, Hiroki; Maeda, Noboru; Tsuboyama, Takahiro; Nakamoto, Atsushi; Tomoda, Kaname; Tomiyama, Noriyuki

    2011-01-01

    Purpose: To investigate the validity of determining the contrast medium dose based on body surface area (BSA) for the abdominal contrast-enhanced multi-detector row CT comparing with determining based on body weight (BW). Materials and methods: Institutional review committee approval was obtained. In this retrospective study, 191 patients those underwent abdominal contrast-enhanced multi-detector row CT were enrolled. All patients received 96 mL of 320 mg I/mL contrast medium at the rate of 3.2 mL. The iodine dose required to enhance 1 HU of the aorta at the arterial phase and that of liver parenchyma at portal venous phase per BSA were calculated (EU BSA ) and evaluated the relationship with BSA. Those per BW were also calculated (EU BW ) and evaluated. Estimated enhancement values (EEVs) of the aorta and liver parenchyma with two protocols for dose decision based on BSA and BW were calculated and patient-to-patient variability was compared between two protocols using the Levene test. Results: The mean of EU BSA and EU BW were 0.0621 g I/m 2 /HU and 0.00178 g I/kg/HU for the aorta, and 0.342 g I/m 2 /HU and 0.00978 g I/kg/HU for the liver parenchyma, respectively. In the aortic enhancement, EU BSA was almost constant regardless of BSA, and the mean absolute deviation of the EEV with the BSA protocol was significantly lower than that with the BW protocol (P < .001), although there was no significant difference between two protocols in the hepatic parenchymal enhancement (P = .92). Conclusion: For the aortic enhancement, determining the contrast medium dose based on BSA was considered to improve patient-to-patient enhancement variability.

  16. Changes in Renal Function in Elderly Patients Following Intravenous Iodinated Contrast Administration: A Retrospective Study

    International Nuclear Information System (INIS)

    Alsafi, A.; Alsafi, Z.; Lakhani, A.; Strickland, N.H.

    2014-01-01

    Contrast-induced nephropathy (CIN) is a recognised complication of intravascular administration of iodinated contrast media (ICM). Previous studies suggest a higher incidence in the elderly, but no large study has assessed this to date. We set out to assess changes in creatinine in elderly inpatients following computed tomography (CT) examination and compare those who received intravenous contrast to those who did not. Methods. Using the Radiology Information System in two teaching hospitals, inpatients over the age of seventy who had a CT examination and a baseline creatinine were identified and their follow-up creatinine levels were analysed. Elderly inpatients who underwent a non contrast CT over the same period were used as controls. Results. 677 elderly inpatients who received ICM were compared with 487 controls. 9.2% of patients who received ICM developed acute kidney injury (AKI) compared to 3.5% of inpatient controls (Ρ<0.0001). Patients with higher baseline eGFR had a higher incidence of post-CT AKI. Conclusions. The incidence of post-CT AKI is higher in patients who received IV ICM compared to those who did not; the difference may be partly attributable to contrast-induced nephropathy. This suggests that the incidence of CIN in the elderly may not be as high as previously thought.

  17. Risk of contrast-medium-induced nephropathy in high-risk patients undergoing MDCT - A pooled analysis of two randomized trials

    International Nuclear Information System (INIS)

    Thomsen, Henrik S.; Morcos, Sameh K.

    2009-01-01

    The incidence of contrast-medium-induced nephropathy (CIN) following intravenous (IV) CM administration of contrast media to renally impaired patients undergoing multidetector computed tomography (MDCT) is not well characterized. Our objective was to investigate the incidence of CIN in patients with glomerular filtration rate (GFR) 40 ml/min, 4.6% when GFR <40 ml/min and 7.8% in patients with GFR <30 ml/min. The incidence of CIN was significantly higher after iodixanol than after LOCM (seven patients, 4.7% following IOCM, no CIN cases following the LOCM; p = 0.007). Significant differences in favor of the LOCM were also observed in patients with GFR <40 ml/min and GFR <30 ml/min. Following the IV administration of nonionic contrast agents in patients with moderate-to-severe renal insufficiency, the risk of significant CIN seems to be low. The IOCM iodixanol caused a higher rate of CIN than the LOCM iopamidol and iomeprol, especially in high-risk patients. Differences in osmolality between these LOCM and iodixanol do not play a role in the genesis of CIN. (orig.)

  18. In vivo dentate nucleus MRI relaxometry correlates with previous administration of Gadolinium-based contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Tedeschi, Enrico; Canna, Antonietta; Cocozza, Sirio; Russo, Carmela; Angelini, Valentina; Brunetti, Arturo [University ' ' Federico II' ' , Neuroradiology, Department of Advanced Biomedical Sciences, Naples (Italy); Palma, Giuseppe; Quarantelli, Mario [National Research Council, Institute of Biostructure and Bioimaging, Naples (Italy); Borrelli, Pasquale; Salvatore, Marco [IRCCS SDN, Naples (Italy); Lanzillo, Roberta; Postiglione, Emanuela; Morra, Vincenzo Brescia [University ' ' Federico II' ' , Department of Neurosciences, Reproductive and Odontostomatological Sciences, Naples (Italy)

    2016-12-15

    To evaluate changes in T1 and T2* relaxometry of dentate nuclei (DN) with respect to the number of previous administrations of Gadolinium-based contrast agents (GBCA). In 74 relapsing-remitting multiple sclerosis (RR-MS) patients with variable disease duration (9.8±6.8 years) and severity (Expanded Disability Status Scale scores:3.1±0.9), the DN R1 (1/T1) and R2* (1/T2*) relaxation rates were measured using two unenhanced 3D Dual-Echo spoiled Gradient-Echo sequences with different flip angles. Correlations of the number of previous GBCA administrations with DN R1 and R2* relaxation rates were tested, including gender and age effect, in a multivariate regression analysis. The DN R1 (normalized by brainstem) significantly correlated with the number of GBCA administrations (p<0.001), maintaining the same significance even when including MS-related factors. Instead, the DN R2* values correlated only with age (p=0.003), and not with GBCA administrations (p=0.67). In a subgroup of 35 patients for whom the administered GBCA subtype was known, the effect of GBCA on DN R1 appeared mainly related to linear GBCA. In RR-MS patients, the number of previous GBCA administrations correlates with R1 relaxation rates of DN, while R2* values remain unaffected, suggesting that T1-shortening in these patients is related to the amount of Gadolinium given. (orig.)

  19. Informed consent for the administration of an intravenous contrast agent: importance and determinants of patient refusal

    International Nuclear Information System (INIS)

    Martel, J.; Garcia-Diaz, J. D.

    1999-01-01

    We proposed to determine the proportion of patients who refuse to undergo intravenous contrast administration and the factors that influence their refusal. Our series consisted of 442 patients who were supposed to undergo imaging studies involving the intravenous injection of an iodine contrast. In a personal interview, the patients were issued a questionnaire specifically designed for this study. The following parameters were recorded: sex, age, inpatient or outpatient status, medical history available, person who informed them about the procedure, person signing the informed consent (patient or other) , highest academic degree, attitude toward receiving the information and degree of concern after reading and signing the consent form. In our series 8.6% of the patients (95% confidence interval: 6-11.2) refused to sign the informed consent form. In addition, there were a number of patients who delayed the procedure or hindered the daily work schedule by some other means. When the relationship between each of the variables studied and refusal to sign the consent form was assessed, significant associations were observed between the latter and the academic level of the patient, his or her degree of concern and having received the information from a trained person. There was also a nearly significant trend toward the association between refusal and the patient's background. Relatively few patients refuse to sign the informed consent to receive intravenous contrast administration but this negative decision interferes with the health care practice. It is possible to identify certain correctable factors that influence the patient in this respect. (Author) 13 refs

  20. An evaluation of ultravist - a contrast medium by Schering in angiography

    International Nuclear Information System (INIS)

    Twarkowski, P.; Woynarowski, M.

    1993-01-01

    An angiography with ''uropolina'' (Polfa), ''hexabrix'' (Byk) and ''ultravist'' (Schering) was performed in 30 patients with various vascular disorders. It has appeared, that low-osmolality contrast media (''hexabrix'') and nonionic ones (''ultravist'') less frequently caused the complications than ''uropolina'', widely used by us. (author)

  1. Contrasting medium and genre on Wikipedia to open up the dominating definition and classification of geoengineering

    OpenAIRE

    Markusson , Nils; Venturini , Tommaso; Laniado , David; Kaltenbrunner , Andreas

    2016-01-01

    International audience; Geoengineering is typically defined as a techno-scientific response to climate change that differs from mitigation and adaptation, and that includes diverse individual technologies, which can be classified as either solar radiation management or carbon dioxide removal. We analyse the representation of geoengineering on Wikipedia as a way of opening up this dominating, if contested, model for further debate. We achieve this by contrasting the dominating model as present...

  2. Indirect MR venography: contrast medium protocols, postprocessing and combination in diagnosing pulmonary emboli with MRI

    International Nuclear Information System (INIS)

    Kluge, A.; Bachmann, G.; Rominger, M.; Schoenburg, M.

    2004-01-01

    Purpose: Integration of MR venography in a comprehensive MR imaging protocol in patients with suspected pulmonary embolism (PE) and evaluation of contrast media dosage, timing and postprocessing for diagnostic accuracy. Materials and Methods: Fortyeight consecutive inpatients with suspected PE or deep vein thrombosis were examined by MR venography according to one of the following protocols: protocol I: MR venography only, 0.25 mmol/kg bodyweight (BW) Gadopentate dimeglumine(Gd-DTPA) as single dose, bolus timing; protocol II: MR angiography of pulmonary arteries with a cumulative dosage of 0.25 mmol/kg contrast media, modification of coil setting for MR venography without further contrast media application; protocol III: as protocol II but with 0.125 mmol/kg BW, followed by MR venography. Signal-to-noise ratio, contrast-to-noise ratio, number of definable vascular segments and image quality were evaluated. The results were compared to conventional bilateral venography. Results: All MR venography examinations were of diagnostic quality and the examination time was below 10 min. MR venography could be performed in all 48 patients comparted to 43 of 48 patients for conventional venography. Significantly more superficial and deep veins of the leg could be visualized by MR venography (94% compared to 83% for conventional venography). Sensitivity and specificity were 100% and 92%, respectively. Quality differed significantly between 0.125 mmol/kg (protocol III) and 0.25 mmol/kg Gd-DTPA (protocols I and II) while timing did not influence quality (protocol I vs. II). (orig.) [de

  3. Effect of Intravenous Administration of Contrast Media on Serum Creatinine Levels in Neonates.

    Science.gov (United States)

    Bedoya, Maria A; White, Ammie M; Edgar, J Christopher; Pradhan, Madhura; Raab, Elisabeth L; Meyer, James S

    2017-08-01

    Purpose To assess the effect of intravenous contrast media on renal function in neonates. Materials and Methods Institutional review board approval was obtained with waiver of consent. Electronic health records from January 2011 to April 2013 were reviewed retrospectively. Measures of renal function were obtained in inpatient neonates who underwent magnetic resonance (MR) imaging or computed tomography (CT) and for whom serum creatinine (Cr) levels were obtained within 72 hours before imaging and at least one time after imaging (>1 day after administration of contrast material). A total of 140 neonates who received contrast material (59 who underwent CT with iohexol or iodixanol and 81 who underwent MR imaging with gadopentetate dimeglumine) were identified. These neonates were frequency matched according to sex, gestational and postnatal age, and preimaging serum Cr levels with neonates who underwent unenhanced MR imaging or CT. Cr levels and glomerular filtration rates (GFRs) were grouped according to when they were obtained (before imaging, 1-2 days after imaging, 3-5 days after imaging, 6-9 days after imaging, 10-45 days after imaging, and more than 45 days after imaging). Serum Cr levels and GFRs for each time period were compared between groups by using hierarchic regressions or χ 2 or Fisher exact tests and with repeated-measures analysis of variance to compare groups on the rate of change in serum Cr levels and GFRs from before to after imaging. Results Cr levels decreased and GFRs increased in both groups from before to after imaging (CT group, P ≤ .01; MR imaging group, P ≤ .01). The neonates who underwent contrast material-enhanced imaging and the neonates who underwent unenhanced imaging showed similar serum Cr levels at all examined time periods. Groups also did not differ in the proportion of neonates with serum Cr levels higher than the reference range (>0.4 mg/dL) at any time point (iodine- [P > .12] or gadolinium-based [P > .13] contrast

  4. Rapid MR measurements of contrast medium dilution kinetics (gadolinium-DTPA) in a flow phantom

    International Nuclear Information System (INIS)

    Boeck, J.C.; Sander, B.; Frank, J.; Schoerner, W.

    1991-01-01

    We studied first-pass MRI-contrast dilution to compute flow and volume of distribution in a realistic flow phantom. Pulsatile flow was provided by a one-chamber artificial heart. Physiological stroke volume, rate, pressure, and flow were adjustable. An elastic tube with dimensions similar to that of the human aorta was imaged at a rate of 2.4 Hz. After contrast injection, an initial increase in signal intensity was followed by a decrease. Signal-intensity-time plots demonstrated slightly skewed curves as expected from dispersion theory. After calibration at different gadolinium-DTPA concentrations, signal intensities were converted into true gadolinium concentrations, and flow was calculated from the concentration-time curves. Flow was varied between 2.5 and 10.0 l/min and a significant correlation was found between the MRI-estimate and true flow. Volume of distribution between injection and detection site was reliably estimated. This study demonstrates rapid 2-D imaging of a paramagnetic contrast bolus in a realistic flow phantom. Reliable estimates of flow and volume are obtained. (orig.) [de

  5. Nanotoxic Profiling of Novel Iron Oxide Nanoparticles Functionalized with Perchloric Acid and SiPEG as a Radiographic Contrast Medium

    Directory of Open Access Journals (Sweden)

    Muhamad Idham Mohamed

    2015-01-01

    Full Text Available Emerging syntheses and findings of new metallic nanoparticles (MNPs have become an important aspect in various fields including diagnostic imaging. To date, iodine has been utilized as a radiographic contrast medium. However, the raise concern of iodine threats on iodine-intolerance patient has led to search of new contrast media with lower toxic level. In this animal modeling study, 14 nm iron oxide nanoparticles (IONPs with silane-polyethylene glycol (SiPEG and perchloric acid have been assessed for toxicity level as compared to conventional iodine. The nanotoxicity of IONPs was evaluated in liver biochemistry, reactive oxygen species production (ROS, lipid peroxidation mechanism, and ultrastructural evaluation using transmission electron microscope (TEM. The hematological analysis and liver function test (LFT revealed that most of the liver enzymes were significantly higher in iodine-administered group as compared to those in normal and IONPs groups P<0.05. ROS production assay and lipid peroxidation indicator, malondialdehyde (MDA, also showed significant reductions in comparison with iodine group P<0.05. TEM evaluation yielded the aberration of nucleus structure of iodine-administered group as compared to those in control and IONPs groups. This study has demonstrated the less toxic properties of IONPs and it may postulate that IONPs are safe to be applied as radiographic contrast medium.

  6. Characterisation of urinary stones in the presence of iodinated contrast medium using dual-energy CT: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jia; Qu, Mingliang; Duan, Xinhui; Takahashi, Naoki; Kawashima, Akira; Leng, Shuai; McCollough, Cynthia H. [Mayo Clinic, Department of Radiology, Rochester, MN (United States)

    2012-12-15

    To develop a dual-energy CT (DECT) method for differentiating uric acid (UA) from non-UA stones in the presence of iodinated contrast medium. Thirty UA and 45 non-UA stones were selected after infra-red spectroscopic analysis and independently placed in a 1.5-ml vial, which was filled first with saline and then with increasing concentrations of iodine. For each condition, tubes were put in a 35-cm water phantom and examined using a dual-source CT system at 100 and 140 kV. Virtual unenhanced images created from CT data sets of the stones in iodine-containing solutions provided position and volume information. This map was used to calculate a CT number ratio to differentiate stone type. A region-growing method was developed to improve the ability to differentiate between UA and non-UA stones with iodinated contrast medium. The sensitivity for detecting UA stones was 100 % for unenhanced images but fell to 18 % with 20 mgI/ml iodine solution and 0 % for higher concentrations. With region growing, the sensitivity for detecting UA stones was increased to 100 %, 82 %, 57 %, 50 % and 21 % for iodine solutions of 20, 40, 60, 80 and 100 mgI/ml. The region-growing method improves differentiation of UA from non-UA stones on contrast-enhanced DECT urograms. (orig.)

  7. Attenuation changes of the normal and ischemic canine kidney. Dynamic CT scanning after intravenous contrast medium bolus

    Energy Technology Data Exchange (ETDEWEB)

    Jaschke, W.; Lipton, M.J.; Boyd, D.P.; Cann, C.; Strauss, L.; Sievers, R.S.

    The potential of CT scanning to explore total and regional renal blood flow was evaluated in a dog model with unilateral renal artery stenosis (n=7, reduction of renal blood flow: 32-75% of base line flow). Attenuation versus time curves were generated for the renal cortex and medulla, as well as for the aorta and renal vein. A fast CT scanner was used which allowed for up to 24 scans/minute at the same level (slice thickness: 10 mm). A total of 10 ml contrast medim was injected into a peripheral vein for each scan series taken. During baseline conditions, the curve of the renal cortex and medulla demonstrated 2 peaks. The first peak was mainly related to early vascular enhancement, whereas the second peak corresponded mainly to the appearance of contrast medium in the distal convolutes and collecting ducts. Ischemia of the kidney resulted in a reduction of the first peak and a flattening of the leading edge slope. Transport of contrast medium through the extravascular compartments of the kidney was delayed during ischemia. Relative renal blood flow was obtained from the CT data by dividing peak enhancement by rise-time as assessed from the cortical curve. All measurements were related to baseline flow and validated by flow measurements using radioactive labeled microspheres (n=5). Correlation was found to be r=0.97. (orig.).

  8. Orotracheal administration of contrast agents: a new protocol for brain tumor targeting.

    Science.gov (United States)

    Bianchi, Andrea; Moncelet, Damien; Lux, François; Plissonneau, Marie; Rizzitelli, Silvia; Ribot, Emeline Julie; Tassali, Nawal; Bouchaud, Véronique; Tillement, Olivier; Voisin, Pierre; Crémillieux, Yannick

    2015-06-01

    The development of new non-invasive diagnostic and therapeutic approaches is of paramount importance in order to improve the outcome of patients with glioblastoma (GBM). In this work we investigated a completely non-invasive pre-clinical protocol to effectively target and detect brain tumors through the orotracheal route, using ultra-small nanoparticles (USRPs) and MRI. A mouse model of GBM was developed. In vivo MRI acquisitions were performed before and after intravenous or orotracheal administration of the nanoparticles to identify and segment the tumor. The accumulation of the nanoparticles in neoplastic lesions was assessed ex vivo through fluorescence microscopy. Before the administration of contrast agents, MR images allowed the identification of the presence of abnormal brain tissue in 73% of animals. After orotracheal or intravenous administration of USRPs, in all the mice an excellent co-localization of the position of the tumor with MRI and histology was observed. The elimination time of the USRPs from the tumor after the orotracheal administration was approximately 70% longer compared with intravenous injection. MRI and USRPs were shown to be powerful imaging tools able to detect, quantify and longitudinally monitor the development of GBMs. The absence of ionizing radiation and high resolution of MRI, along with the complete non-invasiveness and good reproducibility of the proposed protocol, make this technique potentially translatable to humans. To our knowledge, this is the first time that the advantages of a needle-free orotracheal administration route have been demonstrated for the investigation of the pathomorphological changes due to GBMs. Copyright © 2015 John Wiley & Sons, Ltd.

  9. Cytogenetic analysis in peripheral blood lymphocytes after arteriography (exposure to X-rays and contrast medium)

    International Nuclear Information System (INIS)

    Hadjidekova, V.; Popova, L.; Hristova, R.; Hadjidekov, V.

    2006-01-01

    Full text: The purpose of our study is to investigate the cytogenetic effects in peripheral blood lymphocytes of 29 patients who had undergone diagnostic angiography. Peripheral blood samples were taken from 22 patients submitted to renal arteriography and 7 patients submitted to cerebral arteriography (17 male and 12 female, aged between 13 and 68 years). Cytogenetic analysis was performed in peripheral lymphocytes before the procedure, immediately after and 24 hours later. The entrance skin dose obtained during the whole diagnostic X-ray exposure was measured by thermoluminescent dosimeters and varied between 0.03 - 0.30 Gy. Both low and high osmolarity contrast media were used. Chromosomal aberrations and micronuclei frequency was used as biomarkers of genotoxicity. The estimated frequency of chromosomal aberrations and micronuclei in peripheral blood lymphocytes of patients after arteriography examination is significantly higher than the level before the diagnostic exposure. The mean frequency of cells with chromosomal aberrations nearly double after examination and remained constant at 24h analysis. Radiological diagnostic procedures involving iodinated contrast media as arteriography may cause a significant increase of the cytogenetic injury in peripheral blood lymphocytes

  10. Cytogenetic analysis of peripheral blood lymphocytes after arteriography (exposure to x-rays and contrast medium)

    International Nuclear Information System (INIS)

    Popova, L.; Hadjidekova, V.; Karadjov, G.; Agova, S.; Traskov, D.; Hadjidekov, V.

    2005-01-01

    Backgrounds. The purpose of our study is to investigate the cytogenetic analysis findings in peripheral blood lymphocytes of 29 patients who had undergone diagnostic radiography. Methods. Peripheral blood samples were taken from 22 patients submitted to renal arteriography and 7 patients submitted to cerebral arteriography (17 male and 12 female, aged between 13-68 years). Cytogenetic analyses of peripheral lymphocytes were performed before the procedure, immediately after and 24 hours later. The entrance skin dose obtained during the whole diagnostic X-ray exposure was measured by thermoluminescent dosimeters and varied between 0.03-0.30 Gy. Both low and high osmolarity contrast media were used. Chromosomal aberrations and micronuclei frequency were used as biomarkers of genotoxicity. Results. The estimated frequency of chromosomal aberrations and micronuclei in the peripheral blood lymphocytes of patients after arteriography examination was significantly higher than the level before the diagnostic exposure. The mean frequency of cells with chromosomal aberrations was nearly double after examination and proved to be constant in the analysis after 24 hours. Conclusions. Radiological diagnostic procedures involving iodinated contrast media as arteriography may cause a significant increase in cytogenetic damage in peripheral blood lymphocytes. (author)

  11. [Dynamic MR mammography. Multidimensional visualization of contrast medium enhancement in virtual reality].

    Science.gov (United States)

    Englmeier, K H; Griebel, J; Lucht, R; Knopp, M; Siebert, M; Brix, G

    2000-03-01

    The purpose of this study was the development of a method for fast and efficient analysis of dynamic MR images of the female breast. The image data sets were acquired with a saturation-recovery turbo-FLASH sequence which enables the detection of the kinetics of the contrast agent concentration in the whole breast with a high temporal and spatial resolution. In addition, a morphologic 3D-FLASH data set was acquired. The dynamic image datasets were analyzed by a pharmacokinetic model which enables the representation of the relevant functional tissue information by two parameters. In order to display simultaneously morphologic and functional tissue information, we developed a multidimensional visualization system, which enables a practical and intuitive human-computer interface in virtual reality. The developed system allows the fast and efficient analysis of dynamic MR data sets. An important clinical application is the localization and definition of multiple lesions of the female breast.

  12. In vivo magnetic resonance imaging of atherosclerotic lesions with a newly developed Evans blue-DTPA-gadolinium contrast medium in apolipoprotein-E-deficient mice.

    Science.gov (United States)

    Yasuda, Satoshi; Ikuta, Kenjiro; Uwatoku, Toyokazu; Oi, Keiji; Abe, Kohtaro; Hyodo, Fuminori; Yoshimitsu, Kengo; Sugimura, Kohtaro; Utsumi, Hideo; Katayama, Yoshiki; Shimokawa, Hiroaki

    2008-01-01

    Magnetic resonance imaging (MRI) contrast agents that specifically detect atherosclerotic plaque may be useful for the noninvasive detection of the plaque. We have recently developed a new contrast agent, Evans blue-DTPA-gadolinium (EB-DTPA-Gd), which selectively accumulates vascular lesions with endothelial removal. In this study, we examined whether EB-DTPA-Gd is also useful for in vivo imaging of atherosclerotic plaques. We used male apolipoprotein-E-deficient (ApoE-/-) mice of different ages (3, 6 and 12 months old) and age-matched male wild-type mice. After a single intravenous administration of EB-DTPA-Gd (160 microM/kg body weight), MRI T(1) signal was obtained in vivo. Increased signal intensity in the aortic wall was noted within 10-20 min after intravenous injection of EB-DTPA-Gd and was maintained for 30 min. The MRI enhancement in the aorta of ApoE-/- mice was increased in accordance with age, whereas no such enhancement was noted in wild-type mice. Histological examination demonstrated that there was a topological correlation between the site of MRI enhancement and that of atherosclerotic plaque. These results indicate that EB-DTPA-Gd is a useful MRI contrast medium for the in vivo detection of atherosclerotic plaques. Copyright (c) 2007 S. Karger AG, Basel.

  13. Different ways to organize the processes of financial administration : a field study of medium-sized Finnish companies

    OpenAIRE

    Nummela, Maria

    2011-01-01

    This research concentrates on exploring the ways how financial administration is currently organized in medium-sized companies in Finland. Decentralization, centralization and outsourcing are options that are available to different-sized companies. The study was executed as a field study in seven medium-sized Finnish companies that represent different branches. Furthermore, the research method was qualitative theme interview. As large companies have already established their financial service...

  14. Does MRI with oral contrast medium allow single-study depiction of inflammatory bowel disease enteritis and colitis?

    International Nuclear Information System (INIS)

    Cronin, Carmel G.; Lohan, Derek G.; Browne, Ann Michelle; Roche, Clare; Murphy, Joseph M.

    2010-01-01

    To assess the feasibility and utility of magnetic resonance (MR) imaging of the bowel in concurrent small- and large-bowel evaluation for the presence of inflammatory bowel disease (IBD). Over a 5-year period, 62 MR examinations performed on 53 patients demonstrated evidence of IBD. Sixteen of these 53 (30.1%) patients had imaging findings of colonic disease and underwent 19 formal MR small bowel examinations. These were further evaluated for bowel distention and image quality. The sensitivity and specificity of the technique compared with colonoscopy as the 'gold standard' was evaluated. Simultaneous imaging of the colon is feasible at MR small bowel follow-through with moderate-to-excellent colonic visibility and colon distention obtained when the contrast medium is present in the colon at the time of image acquisition. MR imaging had a sensitivity of 80% (0.56-0.93), specificity of 100% (0.77-1.00), positive predictive value (PPV) of 1 and a negative predictive value (NPV) of 0.8 for the identification of colitis (based on available concurrent correlation of 38/62 examinations with colonoscopy). Small and large bowel MR imaging with orally consumed contrast medium represents a promising, feasible, non-invasive, non-radiating single mode of assessment of the entire gastrointestinal tract, performed at a single sitting. (orig.)

  15. Utility of vaginal and rectal contrast medium in MRI for the detection of deep pelvic endometriosis

    International Nuclear Information System (INIS)

    Chassang, M.; Novellas, S.; Bloch-Marcotte, C.; Chevallier, P.; Delotte, J.; Bongain, A.; Toullalan, O.

    2010-01-01

    To study the sensitivity of MRI performed utilising vaginal and rectal opacification with ultrasound gel in the detection of deep pelvic endometriosis. This was a prospective monocentric study. All patients evaluated by the gynaecologist for pelvic pain, endometriosis or infertility were included. Axial and sagittal T2-weighted images were performed both with and without vaginal and rectal opacification with ultrasound gel. Three radiologists, all blinded, interpreted the images with a minimum of 15 days between the two readings. MRI performance with and without vaginal and rectal opacification was evaluated by calculating sensitivity, specificity and both positive and negative predictive values. Seventy-eight patients were included. Among these, 31 patients had deep pelvic endometriosis of which 24 were confirmed by laparoscopy. Seventy-six locations of deep pelvic endometriosis were discovered on MRI. For the three reviewers there was a significant improvement in sensitivity between pre- and post-contrast MRI (p < 0.0002). Opacification of the vagina and rectum significantly improved the sensitivity of MRI for the detection of deep pelvic endometriosis by expanding the vagina and rectum, thus allowing better delineation of the pelvic organs. This was especially apparent for lesions localised to the vagina and rectovaginal septum. (orig.)

  16. Contrasting medium and genre on Wikipedia to open up the dominating definition and classification of geoengineering

    Directory of Open Access Journals (Sweden)

    Nils Markusson

    2016-08-01

    Full Text Available Geoengineering is typically defined as a techno-scientific response to climate change that differs from mitigation and adaptation, and that includes diverse individual technologies, which can be classified as either solar radiation management or carbon dioxide removal. We analyse the representation of geoengineering on Wikipedia as a way of opening up this dominating, if contested, model for further debate. We achieve this by contrasting the dominating model as presented in the encyclopaedic article texts with the patterns of hyper-link associations between the articles. Two datasets were created tracing the geoengineering construct on Wikipedia, shedding light on its boundary with its context, as well as on its internal structure. The analysis shows that the geoengineering category tends to be associated on Wikipedia primarily with atmospheric solar radiation management rather than land-based carbon dioxide removal type technologies. The results support the notion that the dominant model of defining and classifying geoengineering technology has been beneficial for solar radiation management type technologies more than for land-based carbon dioxide removal ones. The article also demonstrates that controversy mapping with Wikipedia data affords analysis that can open up dominating definitions and classifications of technologies, and offer resistance to their frequent naturalising and decontextualising tendencies. This work is in line with recent work on digital sociology, but the article contributes a new methodology and reports on the first empirical application of controversy mapping using Wikipedia data to a technology.

  17. Utility of vaginal and rectal contrast medium in MRI for the detection of deep pelvic endometriosis

    Energy Technology Data Exchange (ETDEWEB)

    Chassang, M.; Novellas, S.; Bloch-Marcotte, C.; Chevallier, P. [Hopital Archet 2, Service d' Imagerie Diagnostique et Interventionnelle, Centre Hospitalier Regional et Universitaire de Nice, 151 route de Saint Antoine de Ginestiere, B.P. 3079, Nice Cedex 3 (France); Delotte, J.; Bongain, A. [Hopital Archet 2, Service de Gynecologie-Obstetrique, Centre Hospitalier Regional et Universitaire de Nice, 151 route de Saint Antoine de Ginestiere, B.P. 3079, Nice Cedex 3 (France); Toullalan, O. [Hopital de Cannes, Service de Gynecologie, 15 avenue des Broussailles, B.P. 264, Cannes Cedex (France)

    2010-04-15

    To study the sensitivity of MRI performed utilising vaginal and rectal opacification with ultrasound gel in the detection of deep pelvic endometriosis. This was a prospective monocentric study. All patients evaluated by the gynaecologist for pelvic pain, endometriosis or infertility were included. Axial and sagittal T2-weighted images were performed both with and without vaginal and rectal opacification with ultrasound gel. Three radiologists, all blinded, interpreted the images with a minimum of 15 days between the two readings. MRI performance with and without vaginal and rectal opacification was evaluated by calculating sensitivity, specificity and both positive and negative predictive values. Seventy-eight patients were included. Among these, 31 patients had deep pelvic endometriosis of which 24 were confirmed by laparoscopy. Seventy-six locations of deep pelvic endometriosis were discovered on MRI. For the three reviewers there was a significant improvement in sensitivity between pre- and post-contrast MRI (p < 0.0002). Opacification of the vagina and rectum significantly improved the sensitivity of MRI for the detection of deep pelvic endometriosis by expanding the vagina and rectum, thus allowing better delineation of the pelvic organs. This was especially apparent for lesions localised to the vagina and rectovaginal septum. (orig.)

  18. Technical innovation: digital tomosynthesis of the hip following intra-articular administration of contrast

    International Nuclear Information System (INIS)

    Gazaille, Roland E.; Flynn, Michael J.; Page, Walter; Finley, Sonia; Holsbeeck, Marnix van

    2011-01-01

    To demonstrate the clinical use of digital tomosynthesis in the depiction of labral and chondral pathology in the setting of post-operative CAM-type impingement of the hip following intra-articular administration of dilute iodinated contrast. We present images from a 46 year-old African American female with suspected CAM-type femoroacetabular impingement (FAI) following percutaneous pinning of the right hip for slipped capital femoral epiphysis (SCFE). A partial tear of the labrum and clinically significant acetabular chondral abnormalities were demonstrated with the use of digital tomosynthesis with superb anatomic detail. Digital tomosynthesis can be of great clinical utility and can depict pathology in superb anatomic detail, particularly in situations in which MRI is not available as well as under circumstances in which artifact due to orthopedic hardware is of concern as shown in this case. (orig.)

  19. Dry preparation for virtual CT colonography with fecal tagging using water-soluble contrast medium: initial results

    International Nuclear Information System (INIS)

    Bielen, Didier; Thomeer, Maarten; Vanbeckevoort, Dirk; Marchal, Guy; Kiss, Gabriel; Maes, Frederik; Rutgeerts, Paul

    2003-01-01

    The purpose of this study was to evaluate the feasibility of a dry bowel preparation, i.e. without laxative fluids, for virtual CT colonography (VCTC), and its impact on patient acceptance compared with conventional colonoscopy (CC). A randomly chosen patient population scheduled for CC (n=11) was first submitted to VCTC after a dry preparation, consisting of low-residue meals combined with a small amount of a iodinated water-soluble contrast medium during each meal 3 days before VCTC. In different colon segments and between different persons, the degree of tagging in VCTC was evaluated and graded. Patient acceptance and future preference were assessed for both preparations as well as for both investigations. The mixing of the contrast with the intestinal content results in contrast impregnated stool, the tagged feces. The degree of fecal tagging was good in the majority of the patients and the colonic segments, especially in the descending colon and sigmoid. Furthermore, patient acceptance and preference were clearly in favour of VCTC compared with CC merely because of the non-invasiveness of the dry preparation. Dry bowel preparation and VCTC is a promising approach towards a patient-friendly colon cancer-screening setup. (orig.)

  20. Contrast Medium Induced Nephropathy after Endovascular Stent Graft Placement: An Examination of Its Prevalence and Risk Factors

    International Nuclear Information System (INIS)

    Kawatani, Yohei; Nakamura, Yoshitsugu; Mochida, Yoshihiko; Yamauchi, Naoya; Hayashi, Yujiro; Taneichi, Tetsuyoshi; Ito, Yujiro; Kurobe, Hirotsugu; Suda, Yuji; Hori, Takaki

    2016-01-01

    Endovascular stent graft placement has become a major treatment for thoracic and abdominal aneurysms. While endovascular therapy is less invasive than open surgery, it involves the use of a contrast medium. Contrast media can cause renal impairment, a condition termed as contrast-induced nephropathy (CIN). This study sought to evaluate the incidence and risk factors of CIN following endovascular stent graft placement for aortic aneurysm repair. The study included 167 consecutive patients who underwent endovascular stent graft placement in our hospital from October 2013 to June 2014. CIN was diagnosed using the European Society of Urogenital Radiology criteria. Patients with and without CIN were compared. Chi-squared tests, t-tests, and multivariate logistic regression analyses were performed. Thirteen patients (7.8%) developed CIN. Left ventricular dysfunction and intraoperative blood transfusion were significantly more frequent in the CIN group (P = 0.017 and P = 0.032, resp.). Multivariate analysis showed that left ventricular dysfunction had the strongest influence on CIN development (odds ratio 9.34, P = 0.018, and 95% CI = 1.46–59.7). Patients with CIN also experienced longer ICU and hospital stays. Measures to improve renal perfusion flow should be considered for patients with left ventricular dysfunction who are undergoing endovascular stent graft placement

  1. Effects of acetylcysteine and probucol on contrast medium-induced depression of intrinsic renal glutathione peroxidase activity in diabetic rats.

    Science.gov (United States)

    Yen, Hsueh-Wei; Lee, Hsiang-Chun; Lai, Wen-Te; Sheu, Sheng-Hsiung

    2007-04-01

    Antioxidants such as N-acetylcysteine and probucol have been used to protect patients from contrast media-induced nephrotoxicity. The mechanisms underlying these protective effects are not well understood. We hypothesized that acetylcysteine and probucol alter the activity of endogenous antioxidant enzyme activity. Four weeks after induction of diabetes with streptozotocin, diabetic and nondiabetic rats were divided into three groups. Group 1 rats did not receive any antioxidant agents. Group 2 rats were treated with acetylcysteine and group 3 rats with probucol for 1 week before injection of the contrast medium diatrizoate (DTZ). We found that diabetic rats had higher renal glutathione peroxidase (GPx) activity than normal rats. DTZ suppressed renal GPx activity significantly in both group 1 diabetic and normal rats. Interestingly, renal GPx activity in both diabetic and normal rats pretreated with acetylcysteine or probucol was not inhibited by DTZ. Renal superoxide dismutase (SOD) increased significantly in normal rats after DTZ injection, but not in diabetic rats. Finally, acetylcysteine or probucol did not significantly influence renal SOD. These findings suggest that the renal protective effects of acetylcysteine and probucol against contrast-induced oxidative stress and nephrotoxicity may be mediated by altering endogenous GPx activity.

  2. Weight-adapted iodinated contrast media administration in abdomino-pelvic CT: Can image quality be maintained?

    Science.gov (United States)

    Perrin, E; Jackson, M; Grant, R; Lloyd, C; Chinaka, F; Goh, V

    2018-02-01

    In many centres, a fixed method of contrast-media administration is used for CT regardless of patient body habitus. The aim of this trial was to assess contrast enhancement of the aorta, portal vein, liver and spleen during abdomino-pelvic CT imaging using a weight-adapted contrast media protocol compared to the current fixed dose method. Thirty-nine oncology patients, who had previously undergone CT abdomino-pelvic imaging at the institution using a fixed contrast media dose, were prospectively imaged using a weight-adapted contrast media dose (1.4 ml/kg). The two sets of images were assessed for contrast enhancement levels (HU) at locations in the liver, aorta, portal vein and spleen during portal-venous enhancement phase. The t-test was used to compare the difference in results using a non-inferiority margin of 10 HU. When the contrast dose was tailored to patient weight, contrast enhancement levels were shown to be non-inferior to the fixed dose method (liver p contrast dose reduction of 165 ml using the weight-adapted method compared to the fixed dose method, with a mean cost per patient of £6.81 and £7.19 respectively. Using a weight-adapted method of contrast media administration was shown to be non-inferior to a fixed dose method of contrast media administration. Patients weighing 76 kg, or less, received a lower contrast dose which may have associated cost savings. A weight-adapted contrast media protocol should be implemented for portal-venous phase abdomino-pelvic CT for oncology patients with adequate renal function (>70 ml/min/1.73 m 2 ). Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  3. Digital subtraction angiography (DSA) of aortocoronary bypass grafts in the early postoperative phase with peripheral-venous contrast medium injection

    International Nuclear Information System (INIS)

    Tuengerthal, S.; Lang, J.; Donhoeffner, A.

    1985-01-01

    Using a fully digitalised subtraction unit, aortocoronary bypass grafts can be visualised in the early postoperative phase by means of peripheral venous contrast medium injection (57 out of a total of 60 cases). In more than one-half of the cases (31 out of a total of 60), it is possible to outline sharply the bypass grafts from the beginning to their entry into the bridged-over coronary artery, in such a manner that any loops, kinks, stenoses or reduced flow rates can be recognised. This examination is not considered to be an invasive one by the patient, and the cardiosurgeon can welcome it as a valuable additional means of controlling and assessing the results of surgery. (orig.) [de

  4. 2D and 3D parameter images for analysis of contrast medium enhancement based on dynamic CT and MR

    International Nuclear Information System (INIS)

    Beier, J.; Stroszczynski, C.; Oellinger, H.; Felix, R.; Buege, T.; Fleck, E.

    1998-01-01

    Aim: For dynamic contrast medium (CM) studies, parameter images exploit specific features of the time/intensity curve (TIC) of each pixel and represent these values in a new image. Existing concepts of two-dimensional CM analysis are extended for three-dimensional applications using adequate computer graphic visualization. Results: In first-pass analyses, TMIP and TG allowed the simultaneous or separted presentation of different temporal phases of the CM bolus. Correlation images emphasized regions with similarities to given TIC patterns. Three-dimensional computer graphic techniques enabled (1) anatomical/function mapping of original image and CM accumulation and (2) fused display of both spatial CM enhancement and color-encoded time of TIC peak in one common image. Conclusions: The quantifiction of presence, magnitude, and time-of-peak of CM accumulation in local image regions supports the assessment of vascularization and of ischemic or necrotic areas. (orig./AJ) [de

  5. The Impact of Injector-Based Contrast Agent Administration on Bolus Shape and Magnetic Resonance Angiography Image Quality.

    Science.gov (United States)

    Jost, Gregor; Endrikat, Jan; Pietsch, Hubertus

    2017-01-01

    To compare injector-based contrast agent (CA) administration with hand injection in magnetic resonance angiography (MRA). Gadobutrol was administered in 6 minipigs with 3 protocols: (a) hand injection (one senior technician), (b) hand injection (6 less-experienced technicians), and (c) power injector administration. The arterial bolus shape was quantified by test bolus measurements. A head and neck MRA was performed for quantitative and qualitative comparison of signal enhancement. A significantly shorter time to peak was observed for protocol C, whereas no significant differences between protocols were found for peak height and bolus width. However, for protocol C, these parameters showed a much lower variation. The MRA revealed a significantly higher signal-to-noise ratio for injector-based administration. A superimposed strong contrast of the jugular vein was found in 50% of the hand injections. Injector-based CA administration results in a more standardized bolus shape, a higher vascular contrast, and a more robust visualization of target vessels.

  6. The strategy of performing non-prophylactic hemodialysis therapy after administration of contrast media in renal insufficiency patients

    International Nuclear Information System (INIS)

    Hokama, Sanehiro; Oda, Masami; Kadekawa, Katsumi

    2007-01-01

    Acute renal failure induced by contrast media is an important problem in renal insufficiency patients. Prophylactic hemodialysis is usually undertaken after the administration of radiocontrast media. However, we decided to cease giving prophylactic hemodialysis from February, 2002 in line with the guidelines regarding dialysis and contrast media administration provided by the European Society of Urogenital Radiology. We reported our policy at the doctor's meeting of hemodialysis therapy and at the meeting of clinical engineering technologists which were held in Okinawa. After the presentation, a questionnaire survey in 28 hospitals was undertaken by telephone. In all the hospitals, prophylactic hemodialysis after the administration of radiocontrast media was still being continued, with the exception of one hospital. We need to enlighten medical staff that the strategy of performing hemodialysis immediately after the administration of contrast media in patients with reduced renal function does not diminish the rate of radiocontrast media-induced nephropathy. (author)

  7. Diagnostic accuracy of surface coil MRI in assessing cartilaginous invasion in laryngeal tumours. Do we need contrast-agent administration?

    International Nuclear Information System (INIS)

    Preda, Lorenzo; Conte, Giorgio; Bonello, Luke; Giannitto, Caterina; Tagliabue, Elena; Raimondi, Sara; Ansarin, Mohssen; De Benedetto, Luigi; Cattaneo, Augusto; Maffini, Fausto; Bellomi, Massimo

    2017-01-01

    To assess the diagnostic accuracy of MRI performed using surface coils, with and without contrast medium, in predicting thyroid and cricoid cartilage infiltration in laryngeal tumours, and to investigate whether the radiologist's experience influences diagnostic accuracy. We retrospectively enrolled patients with biopsy-proven laryngeal cancer who had undergone preoperative staging MRI and open surgery. Two radiologists with different experience (senior vs. junior) reviewed the MR images without (session A1) and with contrast medium (session A2) separately. We calculated the accuracy of MRI with and without contrast medium in detecting infiltration of the thyroid and cricoid cartilages. Interobserver agreement was calculated by Cohen's Kappa (k). Forty-two patients were enrolled, for a total of 62 cartilages. In session A1 the senior and junior radiologists showed an accuracy of 85% and 71%, respectively, with k = 0.53 (0.33-0.72). In session A2 the senior and junior radiologists showed an accuracy of 84% and 77%, respectively, with k = 0.68 (0.49-0.86). Staging of laryngeal tumours with surface coil MRI showed good diagnostic accuracy in assessing cartilaginous infiltration. We observed similar values of diagnostic accuracy for the analysis performed with and without contrast medium for the senior radiologist. (orig.)

  8. Diagnostic accuracy of surface coil MRI in assessing cartilaginous invasion in laryngeal tumours. Do we need contrast-agent administration?

    Energy Technology Data Exchange (ETDEWEB)

    Preda, Lorenzo [Universita degli Studi di Pavia, Department of Clinical-Surgical Diagnostic and Pediatric Sciences, Pavia (Italy); Division of Radiology, National Center of Oncological Hadrontherapy (CNAO Foundation), Pavia (Italy); Conte, Giorgio [Universita degli Studi di Milano, Postgraduation School in Radiodiagnostics, Milan (Italy); Bonello, Luke [Division of Radiology, Poliambulanza Hospital, Brescia (Italy); Giannitto, Caterina [European Institute of Oncology, Division of Radiology, Milan (Italy); Tagliabue, Elena; Raimondi, Sara [European Institute of Oncology, Division of Epidemiology and Biostatistics, Milan (Italy); Ansarin, Mohssen; De Benedetto, Luigi; Cattaneo, Augusto [European Institute of Oncology, Division of Head and Neck Surgery, Milan (Italy); Maffini, Fausto [European Institute of Oncology, Division of Pathology, Milan (Italy); Bellomi, Massimo [European Institute of Oncology, Division of Radiology, Milan (Italy); Universita degli Studi di Milano, Oncology and Haematology/Oncology Department, Milan (Italy)

    2017-11-15

    To assess the diagnostic accuracy of MRI performed using surface coils, with and without contrast medium, in predicting thyroid and cricoid cartilage infiltration in laryngeal tumours, and to investigate whether the radiologist's experience influences diagnostic accuracy. We retrospectively enrolled patients with biopsy-proven laryngeal cancer who had undergone preoperative staging MRI and open surgery. Two radiologists with different experience (senior vs. junior) reviewed the MR images without (session A1) and with contrast medium (session A2) separately. We calculated the accuracy of MRI with and without contrast medium in detecting infiltration of the thyroid and cricoid cartilages. Interobserver agreement was calculated by Cohen's Kappa (k). Forty-two patients were enrolled, for a total of 62 cartilages. In session A1 the senior and junior radiologists showed an accuracy of 85% and 71%, respectively, with k = 0.53 (0.33-0.72). In session A2 the senior and junior radiologists showed an accuracy of 84% and 77%, respectively, with k = 0.68 (0.49-0.86). Staging of laryngeal tumours with surface coil MRI showed good diagnostic accuracy in assessing cartilaginous infiltration. We observed similar values of diagnostic accuracy for the analysis performed with and without contrast medium for the senior radiologist. (orig.)

  9. Kinetics of intravenous radiographic contrast medium injections as used on CT: simulation with time delay differential equations in a basic human cardiovascular multicompartment model.

    Science.gov (United States)

    Violon, D

    2012-12-01

    To develop a multicompartment model of only essential human body components that predicts the contrast medium concentration vs time curve in a chosen compartment after an intravenous injection. Also to show that the model can be used to time adequately contrast-enhanced CT series. A system of linked time delay instead of ordinary differential equations described the model and was solved with a Matlab program (Matlab v. 6.5; The Mathworks, Inc., Natick, MA). All the injection and physiological parameters were modified to cope with normal or pathological situations. In vivo time-concentration curves from the literature were recalculated to validate the model. The recalculated contrast medium time-concentration curves and parameters are given. The results of the statistical analysis of the study findings are expressed as the median prediction error and the median absolute prediction error values for both the time delay and ordinary differential equation systems; these are situated well below the generally accepted maximum 20% limit. The presented program correctly predicts the time-concentration curve of an intravenous contrast medium injection and, consequently, allows an individually tailored approach of CT examinations with optimised use of the injected contrast medium volume, as long as time delay instead of ordinary differential equations are used. The presented program offers good preliminary knowledge of the time-contrast medium concentration curve after any intravenous injection, allowing adequate timing of a CT examination, required by the short scan time of present-day scanners. The injected volume of contrast medium can be tailored to the individual patient with no more contrast medium than is strictly needed.

  10. Investigation of the gastrointestinal tract by means of the first dimerous nonionic x-ray contrast medium (Iotrolan)

    International Nuclear Information System (INIS)

    Troger, J.; Wenzel-Hora, B.I.

    1987-01-01

    The risks with an ionic, water solvent highly osmotic contrast medium (CM) have now led to a monomerous, nonionic CM being used, particularly in the field of gastrointestinal investigation in newborn babies and infants. Thus side effects could be reduced and the quality of the x-rays improved. However, since the monomerous nonionic CM is still hyperosmotic with respect to blood, there is a water shift into the intestinal lumen. This can upset hydration and impair the quality of radiographs. Iotrolan is the first CM isoosmotic to the blood to be used clinically. It has proved to be superior to a monomerous nonionic CM as far as radiographic quality (density and sharpness) is concerned. Fifty-one children, aged 2 days to 19 years, were give Iotrolan. Some of these patients were compared in a double-blind study with a group of children who had been given monomerous nonionic CM. If Iotrolan was given, the good quality of the radiographs remained constant throughout the gastrointestinal tract and details were clearly discernible, even in the rectum. In addition, Iotrolan in the aboral intestinal sections leads to double-contrast pictures and thereby further increases the identifiability of details. The monomerous nonionic CM, however, showed a loss in density and above all in sharpness during its passage. Since Iotrolan is isotonic to blood, its is superior to all other water-solvent CM as far as possible side effects and radiographic quality are concerned

  11. Potentials and limitations of low-concentration contrast medium (150 mg iodine/ml) in CT pulmonary angiography

    International Nuclear Information System (INIS)

    Radon, M.R.; Kaduthodil, M.J.; Jagdish, J.; Matthews, S.; Hill, C.; Bull, M.J.; Morcos, S.K.

    2011-01-01

    Aim: To assess the feasibility of producing diagnostic multidetector computed tomography (MDCT) pulmonary angiography with low iodine concentration contrast media (150 mg iodine/ml) in patients with suspected acute pulmonary embolism. Materials and methods: Ninety-five randomized patients underwent MDCT (64 row) pulmonary angiography with 100 ml iopromide either at low concentration (LC) of 150 mg iodine/ml (n = 45) or high concentration (HC) of 300 mg iodine/ml (n = 50), delivered at the rate of 5 ml/s via a power injector. Two experienced radiologists, blinded to the concentration used, subjectively assessed the diagnostic quality and confidence using a four-point scale [1 = poor (not diagnostic), 2 = satisfactory, 3 = good, 4 = excellent]. Attenuation values (in HU) were measured in the main proximal branches of the pulmonary arteries. Results: The median diagnostic quality score for both observers was 3.5 (interquartile range 3-4) in the HC group and 2.5 (interquartile range 1.5-3) in the LC group (p < 0.01). The median diagnostic confidence score for both observers was 4 (interquartile range 3-4) in the HC group and 3 (interquartile range 1.5-4) in the LC group (p < 0.01). Both observers rated examinations as diagnostic in 69% of cases in the LC group, compared with 96% of cases in the HC group. Good interobserver agreement was found in both groups (K value 0.72 in the LC group and 0.73 in the HC). Obesity, poor scan timing, and dilution by venous return of non-opacified blood were the main reasons for a reduction in diagnostic quality of examinations in the LC group. Conclusion: Despite a 50% reduction of contrast medium dose in comparison to the standard technique, 150 mg iodine/ml can produce diagnostic MDCT pulmonary angiogram studies in the absence of obesity or high cardiac output and hyper-dynamic pulmonary circulation. Reducing the dose of contrast media would minimize the risk of contrast nephropathy in patients at risk of this complication

  12. Submillisievert standard-pitch CT pulmonary angiography with ultra-low dose contrast media administration: A comparison to standard CT imaging.

    Science.gov (United States)

    Suntharalingam, Saravanabavaan; Mikat, Christian; Stenzel, Elena; Erfanian, Youssef; Wetter, Axel; Schlosser, Thomas; Forsting, Michael; Nassenstein, Kai

    2017-01-01

    To evaluate the image quality and radiation dose of submillisievert standard-pitch CT pulmonary angiography (CTPA) with ultra-low dose contrast media administration in comparison to standard CTPA. Hundred patients (56 females, 44 males, mean age 69.6±15.4 years; median BMI: 26.6, IQR: 5.9) with suspected pulmonary embolism were examined with two different protocols (n = 50 each, group A: 80 kVp, ref. mAs 115, 25 ml of contrast medium; group B: 100 kVp, ref. mAs 150, 60 ml of contrast medium) using a dual-source CT equipped with automated exposure control. Objective and subjective image qualities, radiation exposure as well as the frequency of pulmonary embolism were evaluated. There was no significant difference in subjective image quality scores between two groups regarding pulmonary arteries (p = 0.776), whereby the interobserver agreement was excellent (group A: k = 0.9; group B k = 1.0). Objective image analysis revealed that signal intensities (SI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the pulmonary arteries were equal or significantly higher in group B. There was no significant difference in the frequency of pulmonary embolism (p = 0.65). Using the low dose and low contrast media protocol resulted in a radiation dose reduction by 71.8% (2.4 vs. 0.7 mSv; pcontrast agent volume can obtain sufficient image quality to exclude or diagnose pulmonary emboli while reducing radiation dose by approximately 71%.

  13. The influence of different contrast medium concentrations and injection protocols on quantitative and clinical assessment of FDG–PET/CT in lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Verburg, Frederik A., E-mail: fverburg@ukaachen.de [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany); Maastricht University Medical Center, Department of Nuclear Medicine, P. Debyelaan 25, 6229 HX Maastricht (Netherlands); Kuhl, Christiane K. [RWTH Aachen University Hospital, Department of Diagnostic and Interventional Radiology, Pauwelsstraße 30, 52074 Aachen (Germany); Pietsch, Hubertus [Bayer Pharma AG, Berlin, Müllerstrasse 178, 13353 Berlin (Germany); Palmowski, Moritz [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany); Mottaghy, Felix M. [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany); Maastricht University Medical Center, Department of Nuclear Medicine, P. Debyelaan 25, 6229 HX Maastricht (Netherlands); Behrendt, Florian F. [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany)

    2013-10-01

    Objectives: To compare the effects of two different contrast medium concentrations for use in computed X-ray tomography (CT) employing two different injection protocols on positron emission tomography (PET) reconstruction in combined 2-{sup 18}F-desoxyglucose (FDG) PET/CT in patients with a suspicion of lung cancer. Methods: 120 patients with a suspicion of lung cancer were enrolled prospectively. PET images were reconstructed with the non-enhanced and venous phase contrast CT obtained after injection of iopromide 300 mg/ml or 370 mg/ml using either a fixed-dose or a body surface area adapted injection protocol. Maximum and mean standardized uptake values (SUVmax and SUVmean) and contrast enhancement (HU) were determined in the subclavian vein, ascending aorta, abdominal aorta, inferior vena cava, portal vein, liver and kidney and in the suspicious lung lesion. PET data were evaluated visually for the presence of malignancy and image quality. Results: At none of the sites a significant difference in the extent of the contrast enhancement between the four different protocols was found. However, the variability of the contrast enhancement at several anatomical sites was significantly greater in the fixed dose groups than in the BSA groups for both contrast medium concentrations. At none of the sites a significant difference was found in the extent of the SUVmax and SUVmean increase as a result of the use of the venous phase contrast enhanced CT for attenuation. Visual clinical evaluation of lesions showed no differences between contrast and non-contrast PET/CT (P = 0.32). Conclusions: Contrast enhanced CT for attenuation correction in combined PET/CT in lung cancer affects neither the clinical assessment nor image quality of the PET-images. A body surface adapted contrast medium protocol reduces the interpatient variability in contrast enhancement.

  14. MRI cisternography with gadolinium-containing contrast medium: its role, advantages and limitations in the investigation of rhinorrhoea.

    Science.gov (United States)

    Aydin, K; Guven, K; Sencer, S; Jinkins, J R; Minareci, O

    2004-01-01

    Our purpose was to evaluate the utility of intrathecal gadopentetate dimeglumine -enhanced magnetic resonance cisternography (GdMRC). We injected 0.5 ml contrast medium into the subarachnoid space via lumbar puncture in 20 patients with suspected cerebrospinal fluid (CSF) rhinorrhoea. MRC showed CSF leakage in 14 patients with rhinorrhoea at the time of the examination, into the ethmoid air cells in nine, the sphenoid sinus in three and the frontal sinus in two cases. In 12 of these the site leakage was confirmed during surgical repair of the fistula. No leakage was observed in four patients with intermittent rhinorrhoea, not present at the time of the examination. GdMRC showed leakage in two patients with negative CT cisternography. GdMRC may prove better than CT cisternography, especially with slow CSF flow. We also showed low-dose GdMRC to be a feasible and relative safe way of confirming the presence of and localising active CSF leaks prior to surgical repair.

  15. MRI cisternography with gadolinium-containing contrast medium: its role, advantages and limitations in the investigation of rhinorrhoea

    International Nuclear Information System (INIS)

    Aydin, K.; Guven, K.; Sencer, S.; Minareci, O.; Jinkins, J.R.

    2004-01-01

    Our purpose was to evaluate the utility of intrathecal gadopentetate dimeglumine -enhanced magnetic resonance cisternography (GdMRC). We injected 0.5 ml contrast medium into the subarachnoid space via lumbar puncture in 20 patients with suspected cerebrospinal fluid (CSF) rhinorrhoea. MRC showed CSF leakage in 14 patients with rhinorrhoea at the time of the examination, into the ethmoid air cells in nine, the sphenoid sinus in three and the frontal sinus in two cases. In 12 of these the site leakage was confirmed during surgical repair of the fistula. No leakage was observed in four patients with intermittent rhinorrhoea, not present at the time of the examination. GdMRC showed leakage in two patients with negative CT cisternography. GdMRC may prove better than CT cisternography, especially with slow CSF flow. We also showed low-dose GdMRC to be a feasible and relative safe way of confirming the presence of and localising active CSF leaks prior to surgical repair. (orig.)

  16. The experimental study of the effect of dexamethasone, lidocaine and contrast medium on the activity of collagenase

    International Nuclear Information System (INIS)

    Wu Zhiqun; Liu Weimin; Li Zhonghua; Yang Peng

    2007-01-01

    Objective: To study the effects of hormone, anesthetic and contrast medium on the activities of collagenase lysis. Methods: Nuclear tissues were divided into equal amount for different groups and same units of collagenase were used for the lysis. The only difference in the control group from experimental groups was that there were no dexamethasone, lidocaine or omnipaque but existing in experimental groups. Twenty four hours later, the concentrations of the hydroxyproline were determined in different groups and the data were analyzed by statistical software with computer. Results: 1. The concentrations of hydroxyproline in the dexamethasone group, lidocaine group and omnipaque group were significantly lower than that of control group, especially that of lidocaine group, P value was <0.05 or 0.01. 2. The concentrations of hydroxyproline in the dexamethasone + lidocaine group, dexamethasone + omnipaque group, lidocaine+omnipaque group and dexamethasone + lidocaine + omnipaque group were significantly lower than that of control group; and simultaneously lower in dexamethasone group, lidocaine group, omnipaque group respectively; P value was also <0.05 or 0.01. Conclusion: Dexamethasone, lidocaine and omnipaque can individually inhibit the activity of collagenase at different degrees, so they shouldn't be used together with collagenase in treating the lumber disc herniation. (authors)

  17. Intra-arterial digital subtraction portography with a blood-isotonic, non-ionic, dimeric contrast medium

    International Nuclear Information System (INIS)

    Minakuchi, Kazuo; Tamaoka, Koichi; Nishio, Hiroshi; Matsuo, Ryoichi; Takada, Keiji; Morimoto, Atsuko; Toyoshima, Masami; Murata, Katsuko; Onoyama, Yasuto

    1993-01-01

    Intra-arterial digital subtraction portography (IA-DSP) with a blood-isotonic, non-ionic, dimeric contrast medium was carried out in 27 patients with hepatocellular carcinoma. It was possible to obtain images of excellent or good quality of the portal vein and its bilateral main branches in all patients. The third-order branches of the portal vein in the right lobe could be identified in all patients, and images of excellent or good quality were obtained in a mean of 80.2% of patients. Images of third-order branches in the left lobe were of lower quality than those of third-order branches in the right lobe; in particular, images obtained were of poor quality for 27.3% of the medial branches of the left lobe. It was impossible to identify the caudal branches in almost all patients. The side effects of IA-DSP, pain and sensations of heat were very mild; only one patient complained of mild pain, while 18 patients (69.2%) complained of no sensations of heat whatsoever. (author)

  18. Experimental investigations on the influence of the contrast medium Iopamiro 300 mixed with vegetal mucus on the nasolacrimal system and external eye tissues

    International Nuclear Information System (INIS)

    Rubaj, B.; Koper, S.; Wolski, T.; Toczowski, J.; Wolski, J.; Langwinska-Wosko, E.

    1994-01-01

    Using low osmolality, nonionized contrast medium Iopamiro-300, Bracco mixed with the mucus prepared from the seed flax (''Linum usitatissimum, L.''), a dacryocistorhinography was performed experimentally on 8 healthy mongrel dogs. Assessing the occurrence of local and general complications was the aim of the investigation. On the basis of a radiographic examination it has been shown that the mixture of the contrast medium and seed flax mucus appeared to be a very useful compound for dacryocistorhinography, especially for the evaluation of nasolacrimal duct system course and its patency. Clinical observations and a histological examination proved that this compound of the contrast medium was well tolerated by the mucous membrane of the nasolacrimal system and the external eye tissues. (author). 21 refs, 4 figs

  19. Effects of changes in analytic variables and contrast medium on estimation of glomerular filtration rates by computed tomography in healthy dogs.

    Science.gov (United States)

    Matsuda, Yuri; Kishimoto, Miori; Kushida, Kazuya; Yamada, Kazutaka; Shimizu, Miki; Itoh, Hiroshi

    2017-09-01

    OBJECTIVE To investigate effects of changes in analytic variables and contrast medium osmolality on glomerular filtration rate estimated by CT (CT-GFR) in dogs. ANIMALS 4 healthy anesthetized Beagles. PROCEDURES GFR was estimated by inulin clearance, and dogs underwent CT-GFR with iodinated contrast medium (iohexol or iodixanol) in a crossover-design study. Dynamic renal CT scanning was performed. Patlak plot analysis was used to calculate GFR with the renal cortex or whole kidney selected as the region of interest. The renal cortex was analyzed just prior to time of the second cortical attenuation peak. The whole kidney was analyzed 60, 80, 100, and 120 seconds after the appearance of contrast medium. Automated GFR calculations were performed with preinstalled perfusion software including 2 noise reduction levels (medium and strong). The CT-GFRs were compared with GFR estimated by inulin clearance. RESULTS There was no significant difference in CT-GFR with iohexol versus iodixanol in any analyses. The CT-GFR at the renal cortex, CT-GFR for the whole kidney 60 seconds after appearance of contrast medium, and CT-GFR calculated by perfusion software with medium noise reduction did not differ significantly from GFR estimated by inulin clearance. The CT-GFR was underestimated at ≥ 80 seconds after contrast medium appearance (whole kidney) and when strong noise reduction was used with perfusion CT software. CONCLUSIONS AND CLINICAL RELEVANCE Selection of the renal cortex as region of interest or use of the 60-second time point for whole-kidney evaluation yielded the best CT-GFR results. The perfusion software used produced good results with appropriate noise reduction. IMPACT FOR HUMAN MEDICINE The finding that excessive noise reduction caused underestimation of CT-GFR suggests that this factor should also be considered in CT-GFR examination of human patients.

  20. Fixed drug eruption induced by an iodinated non-ionic X-ray contrast medium: a practical approach to identify the causative agent and to prevent its recurrence

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Ingrid; Block, Wolfgang; Schild, Hans H. [University of Bonn, Department of Radiology, Bonn (Germany); Medina, Jesus; Prieto, Pilar [JUSTESA IMAGEN SA, Biological R and D Department, Madrid (Spain)

    2007-02-15

    We describe the case of a 61-year-old physician who developed a fixed drug eruption (FDE) after i.v. administration of a non-ionic monomeric iodinated X-ray contrast medium (CM) (iopromide). During CM injection, a sensation of heat occurred, which was most intense in the right inguinal region. Four hours later, the FDE arose with a red macule of approximately 2 cm in diameter covering a dermal infiltration in the right inguinal region, and enlarged up to a final size of 15 x 8 cm, accompanied by a burning sensation. The patient's history revealed a similar reaction in the same localization and of the same clinical appearance after CM injection 1 year before. Patch testing 4 months later revealed positive reactions to iomeprol and iohexol. Iopamidol injection for another CT examination 23 months later was well tolerated. Based on these results, we suggest patch testing after CM-induced FDE, which could help to select a CM for future CT examinations. Late onset of adverse CM reactions may manifest as FDE. Patch testing within the previous skin reaction area is the diagnostic tool that should be used to confirm the suspected agent, possible cross-reacting agents and well-tolerated agents. (orig.)

  1. Fixed drug eruption induced by an iodinated non-ionic X-ray contrast medium: a practical approach to identify the causative agent and to prevent its recurrence

    International Nuclear Information System (INIS)

    Boehm, Ingrid; Block, Wolfgang; Schild, Hans H.; Medina, Jesus; Prieto, Pilar

    2007-01-01

    We describe the case of a 61-year-old physician who developed a fixed drug eruption (FDE) after i.v. administration of a non-ionic monomeric iodinated X-ray contrast medium (CM) (iopromide). During CM injection, a sensation of heat occurred, which was most intense in the right inguinal region. Four hours later, the FDE arose with a red macule of approximately 2 cm in diameter covering a dermal infiltration in the right inguinal region, and enlarged up to a final size of 15 x 8 cm, accompanied by a burning sensation. The patient's history revealed a similar reaction in the same localization and of the same clinical appearance after CM injection 1 year before. Patch testing 4 months later revealed positive reactions to iomeprol and iohexol. Iopamidol injection for another CT examination 23 months later was well tolerated. Based on these results, we suggest patch testing after CM-induced FDE, which could help to select a CM for future CT examinations. Late onset of adverse CM reactions may manifest as FDE. Patch testing within the previous skin reaction area is the diagnostic tool that should be used to confirm the suspected agent, possible cross-reacting agents and well-tolerated agents. (orig.)

  2. Polysorbate 80 and low-osmolality water-soluble contrast medium enema in diagnosis and treatment of faecal obstruction in malignant phaeochromocytoma

    International Nuclear Information System (INIS)

    Ratcliffe, J.F.

    1986-01-01

    Stercoral obstruction in a young woman with disseminated phaeochromocytoma was diagnosed and treated successfully using an enema of isosmolar iohexol (Omnipaque) and 1% polysorbate 80 (Tween 80) without complication. Surgical intervention was thus avoided. A low osmolality water-soluble contrast medium (iohexol 150 mg I/ml) with a wetting agent (1% Tween 80) was used because a barium suspension would have inspissated, exacerbating the constipation and a hyperosmolar contrast medium might have precipitated a hypertensive crisis and destablished her critical salt and water balance. (orig.)

  3. Multi-detector CT urography: effect of oral hydration and contrast medium volume on renal parenchymal enhancement and urinary tract opacification - a quantitative and qualitative analysis

    International Nuclear Information System (INIS)

    Szolar, Dieter H.; Tillich, Manfred; Preidler, Klaus W.

    2010-01-01

    To assess the effect of oral hydration and contrast-medium volume on renal enhancement and urinary tract opacification in multi-detector CT urography. A total of 192 patients were assigned to different protocols with varying doses of contrast agent with and without oral hydration. The attenuation was measured in the renal parenchyma in the unenhanced, nephrographic and excretory phase, and in the urinary tract in excretory phase imaging, respectively. Opacification of the urinary tract was graded on volume rendered images. Oral hydration did not significantly alter renal parenchymal enhancement in both the nephrographic and the excretory phase (p > 0.001), but significantly decreased mean attenuation of the urinary tract in the excretory phase (p ≤ 0.001), and improved continuous opacification of all ureter segments (p < 0.01). Higher volumes of contrast medium improved renal parenchymal enhancement (p ≤ 0.001) and continuous opacification of the urinary tract (p ≤ 0.01). Oral hydration leads to lower attenuation values in the urinary tract but improves the continuous opacification of the tract. Increase in contrast medium volume leads to higher renal parenchymal enhancement as well as to an increased continuous opacification of the urinary tract. Decrease in contrast medium volume cannot be compensated for by oral hydration in terms of parenchymal enhancement. (orig.)

  4. High-pitch coronary CT angiography at 70 kVp adopting a protocol of low injection speed and low volume of contrast medium

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Ruiqi; Liu, Xiao Fei; Zhao, Yu; Zhang, Liang [Dept. of Radiology, The First Affiliated Hospital of China Medical University, Shenyang (China); Tong, Jia Jie [Dept. of Radiology, Hebei General Hospital, Shijiazhuang(China)

    2017-09-15

    To evaluate the feasibility and image quality (IQ) of prospectively high-pitch coronary CT angiography (CCTA) with low contrast medium injection rate at 70 kVp. One hundred and four patients with suspected coronary artery disease (body mass index < 26 kg/m{sup 2}, sinus rhythm and heart rate < 70 beats/min) were prospectively enrolled and randomly divided into two groups. In group A and group B, 28 mL and 40 mL of 370 mgI/mL iodinated contrast media was administrated at a flow rate of 3.5 and 5 mL/s, respectively. CT values, noise, signal-to-noise ratio, contrast-to-noise ratio (CNR) of the proximal segments of coronary arteries and subjective IQ were evaluated. The CT values and noise in group A were significantly lower than those in group B (434–485 Hounsfield units [HU] vs. 772–851 HU, all p < 0.001; 17.8–22.3 vs. 23.3–26.4, all p < 0.005). The CNRs of the right coronary artery and left main artery showed no statistical difference between the two groups (42.1 ± 13.8 vs. 36.8 ± 16.0, p = 0.074; 38.7 ± 10.6 vs. 38.1 ± 17.0, p = 0.819). No statistical difference was observed between the two groups in IQ scores (3.04 ± 0.75 vs. 3.0 ± 0.79, p = 0.526) and diagnostic ratio (96.1% [50/52] vs. 94.2% [49/52], p = 0.647). Prospective high-pitch CCTA at 70 kVp with 28 mL of contrast media and injection rate of 3.5 mL/s could provide diagnostic IQ for normal-weight patients with heart rate of < 70 beats/min.

  5. Oral gadopentetate dimeglumine administration as a negative gastrointestinal contrast agent to improve image quality of MR cholangiopancreatography

    International Nuclear Information System (INIS)

    Chen Yi; Xu Yikai; Zhao Yuhui; Wang Guisheng

    2008-01-01

    Objective: To choose optimal concentration and volume of Gd-DTPA solution as a oral gastrointestinal negative contrast agent for MRCP. To evaluate the role of Gd-DTPA solution in improving image quality of MRCP. Methods: In vitro experiment: Gd-DTPA solution was made with different concentrations. T 1 WI, T 2 WI, two-dimensional single slice fast spin echo sequence and three-dimensional half-fourier acquisition single-shot fast spin echo sequence were performed to measure the signal intensity of these contrast agents respectively, so Gd-DTPA solution with the optimal concentration can be decided as oral negative gastrointestinal contrast agent on MRCP. Clinical study: The Gd-DTPA solution with optimal concentration and volume was regarded as an oral negative gastrointestinal contrast agent of MRCP. Twenty- four' patients were performed with MRCP before and after (5-10 minutes and 10-15 minutes) administration of oral negative gastrointestinal contrast agent and image quality was analyzed. Statistical analysis was performed using analysis of variance with SPSS 10.0. Results: When the concentration of Gd-DTPA solution was ≤0.01 mol/L, the contrast agent was hyperintense on T 1 WI. On T 2 WI, when the concentration was ≥0.015 mol/L, it was as hypointense as basic ground; On 2D FSE MRCP images, controls were hyperintense and the contrast agent with concentration ranging from 0.0025 mol/L to 0.03 mol/L was hypointense. On 3D HEAST MRCP image, controls were hyperintense and when the concentration of Gd-DTPA was ≥0.01 mol, the contrast agent was hypointense. The Gd-DTPA solution with the concentration of 0.01 mol/L and the volume of 100 ml was chosen as MRCP oral negative gastrointestinal contrast agent. On MRCP images after oral administration of the contrast agent, in 10-15 minutes, the average grade scores within 24 patients of the intrahepatic bile duct, the common hepatic bile duct, the gall bladder, the common bile duct and pancreatic duct (the average grade

  6. Vascular air embolism after contrast administration on 64 row multiple detector computed tomography: A prospective analysis

    Directory of Open Access Journals (Sweden)

    Kushaljit S Sodhi

    2015-01-01

    Full Text Available Background: Vascular air embolism is being progressively reported as a nonfatal event with increase in use of computed tomography (CT as a diagnostic modality. This study was undertaken to study the frequency and site of vascular air embolism in patients undergoing contrast-enhanced CT (CECT and analyze CT parameters that influence its prevalence and final outcome. Materials and Methods: This was a prospective study approved by departmental ethics committee. Presence and location of air emboli in 200 patients who underwent CT scan of chest on a 64 detector scanner was recorded. We analyzed the role of various factors that could influence the prevalence of air embolism after injection of contrast in CECT scans. These factors included the amount of contrast injected, rate of flow of injection of contrast, site of injection of contrast, and size of intravenous access line. Results: Iatrogenic vascular air emboli were seen in 14 patients (7% of total. The locations of air emboli were main pulmonary artery in 12 (6% of total, left brachiocephalic vein in 3 (1.5% of total, right atrial appendage in 4 (2% of total, and superior vena cava (SVC in 1 (0.5% patient. There was no association between volume of contrast, flow rate, site and size of intravenous access, and presence of air emboli. Conclusion: Radiologists as well as referring physicians should be aware of vascular air embolism, which can occur after contrast injection in patients undergoing CT scan. Age, volume of contrast, flow rate of pressure injector, and site and size of venous cannula do not influence the likelihood or incidence of detection of venous air emboli on CT scans.

  7. The Impact of Injector-Based Contrast Agent Administration on Bolus Shape and Magnetic Resonance Angiography Image Quality

    Directory of Open Access Journals (Sweden)

    Gregor Jost

    2017-04-01

    Full Text Available Objective: To compare injector-based contrast agent (CA administration with hand injection in magnetic resonance angiography (MRA. Methods: Gadobutrol was administered in 6 minipigs with 3 protocols: (a hand injection (one senior technician, (b hand injection (6 less-experienced technicians, and (c power injector administration. The arterial bolus shape was quantified by test bolus measurements. A head and neck MRA was performed for quantitative and qualitative comparison of signal enhancement. Results: A significantly shorter time to peak was observed for protocol C, whereas no significant differences between protocols were found for peak height and bolus width. However, for protocol C, these parameters showed a much lower variation. The MRA revealed a significantly higher signal-to-noise ratio for injector-based administration. A superimposed strong contrast of the jugular vein was found in 50% of the hand injections. Conclusions: Injector-based CA administration results in a more standardized bolus shape, a higher vascular contrast, and a more robust visualization of target vessels.

  8. The use of dilute calogen[reg] as a fat density oral contrast medium in upper abdominal computed tomography, compared with the use of water and positive oral contrast media

    International Nuclear Information System (INIS)

    Ramsay, Duncan W.; Markham, Derrian H.; Morgan, Bruno; Rodgers, Peter M.; Liddicoat, Amanda J.

    2001-01-01

    AIM: Oral contrast media are commonly given prior to computed tomography (CT) examination of the upper abdomen. Although positive oral contrast media are normally used, there is increasing interest in using negative agents such as water and less commonly fat density products. The aim of this study was to compare a positive oral contrast medium, water, and a diluted emulsion of arachis oil (Calogen[reg], a fat density food supplement) for assessment of the upper abdomen. MATERIALS AND METHODS: Seventy-one patients referred for upper abdominal CT were randomized to receive either 500 ml water, 2% sodium diatrizoate or a dilute suspension of Calogen[reg]. The CT images were scored independently by three radiologists. Distension and anatomical identification was assessed for the stomach, duodenum and jejunum; with anatomical identification recorded for the pancreas, retroperitoneum, liver, gallbladder and spleen. RESULTS: Dilute Calogen[reg] produced a significant improvement (P < 0.01) in distension and anatomical visualization of the stomach and proximal duodenum. Only minimal differences were demonstrated between the three contrast media for visualization of more distal small bowel or identification of the other upper abdominal viscera. Significantly more artifacts were caused by positive contrast media than with the Calogen[reg] mixture. CONCLUSION: A dilute suspension of Calogen[reg] as an oral contrast medium is recommended when disease is suspected within the stomach or proximal duodenum. Ramsay, D.W. et al. (2001)

  9. The impact of injector-based contrast agent administration in time-resolved MRA.

    Science.gov (United States)

    Budjan, Johannes; Attenberger, Ulrike I; Schoenberg, Stefan O; Pietsch, Hubertus; Jost, Gregor

    2018-05-01

    Time-resolved contrast-enhanced MR angiography (4D-MRA), which allows the simultaneous visualization of the vasculature and blood-flow dynamics, is widely used in clinical routine. In this study, the impact of two different contrast agent injection methods on 4D-MRA was examined in a controlled, standardized setting in an animal model. Six anesthetized Goettingen minipigs underwent two identical 4D-MRA examinations at 1.5 T in a single session. The contrast agent (0.1 mmol/kg body weight gadobutrol, followed by 20 ml saline) was injected using either manual injection or an automated injection system. A quantitative comparison of vascular signal enhancement and quantitative renal perfusion analyses were performed. Analysis of signal enhancement revealed higher peak enhancements and shorter time to peak intervals for the automated injection. Significantly different bolus shapes were found: automated injection resulted in a compact first-pass bolus shape clearly separated from the recirculation while manual injection resulted in a disrupted first-pass bolus with two peaks. In the quantitative perfusion analyses, statistically significant differences in plasma flow values were found between the injection methods. The results of both qualitative and quantitative 4D-MRA depend on the contrast agent injection method, with automated injection providing more defined bolus shapes and more standardized examination protocols. • Automated and manual contrast agent injection result in different bolus shapes in 4D-MRA. • Manual injection results in an undefined and interrupted bolus with two peaks. • Automated injection provides more defined bolus shapes. • Automated injection can lead to more standardized examination protocols.

  10. Longitudinal study of iodine in toenails following IV administration of an iodine-containing contrast agent

    International Nuclear Information System (INIS)

    Spate, V.L.; Morris, J.S.; Nichols, T.A.; Baskett, C.K.; Mason, M.M.; Horsman, T.L.; McDougall, I.R.

    1998-01-01

    The literature on the relationship between diet and thyroid cancer (TC) risk and the higher incidence of TC among Asian immigrants to the US compared to second and third generation subgroups has prompted epidemiologists to hypothesize that increased levels of iodine consumption may be associated with TC risk, particularly among persons with a history of clinical or subclinical thyroid dysfunction. At the University of Missouri Research Reactor (MURR), we have applied epiboron neutron activation analysis to investigate human nails as a dietary monitor for iodine. Preliminary studies have indicated a positive correlation between dietary iodine intake and the concentration of iodine in toenails. However, these studies are confounded by high iodine levels (up to 30 ppm) in approximately 5% of the nails studied. We hypothesize that, in the subjects we have studied, the high iodine levels may be due to iodine-containing medications, in particular contrast-agents containing iopamidol. This paper will report on longitudinal studies using contrast agent subjects who where followed-up for almost two years compared to a longitudinal control and a population mean. Based on this study, we suggest that iodine-containing contrast agents contaminate nail samples via non-specific binding in the short term followed by incorporation in the nail as a result of absorption. (author)

  11. Low-tube-voltage (80 kVp) CT aortography using 320-row volume CT with adaptive iterative reconstruction: lower contrast medium and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chien-Ming; Chu, Sung-Yu; Hsu, Ming-Yi [Chang Gung University, Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital Linkou, College of Medicine, Taoyuan (China); Liao, Ying-Lan [National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Tsai, Hui-Yu [Chang Gung University, Department of Medical Imaging and Radiological Sciences, College of Medicine, Taoyuan (China); Chang Gung University, Healthy Aging Research Center, Taoyuan (China); Chang Gung University, Department of Medical Imaging and Radiological Sciences, Taoyuan (China)

    2014-02-15

    To evaluate CT aortography at reduced tube voltage and contrast medium dose while maintaining image quality through iterative reconstruction (IR). The Institutional Review Board approved a prospective study of 48 patients who underwent follow-up CT aortography. We performed intra-individual comparisons of arterial phase images using 120 kVp (standard tube voltage) and 80 kVp (low tube voltage). Low-tube-voltage imaging was performed on a 320-detector CT with IR following injection of 40 ml of contrast medium. We assessed aortic attenuation, aortic attenuation gradient, image noise, contrast-to-noise ratio (CNR), volume CT dose index (CTDI{sub vol}), and figure of merit (FOM) of image noise and CNR. Two readers assessed images for diagnostic quality, image noise, and artefacts. The low-tube-voltage protocol showed 23-31 % higher mean aortic attenuation and image noise (both P < 0.01) than the standard-tube-voltage protocol, but no significant difference in the CNR and aortic attenuation gradients. The low-tube-voltage protocol showed a 48 % reduction in CTDI{sub vol} and an 80 % increase in FOM of CNR. Subjective diagnostic quality was similar for both protocols, but low-tube-voltage images showed greater image noise (P = 0.01). Application of IR to an 80-kVp CT aortography protocol allows radiation dose and contrast medium reduction without affecting image quality. (orig.)

  12. Contrast-enhanced voiding urosonography (ceVUS) with the intravesical administration of the ultrasound contrast agent Optison™ for vesicoureteral reflux detection in children: a prospective clinical trial.

    Science.gov (United States)

    Ntoulia, Aikaterini; Back, Susan J; Shellikeri, Sphoorti; Poznick, Laura; Morgan, Trudy; Kerwood, Joanne; Christopher Edgar, J; Bellah, Richard D; Reid, Janet R; Jaramillo, Diego; Canning, Douglas A; Darge, Kassa

    2018-02-01

    Contrast-enhanced voiding urosonography (ceVUS) is widely used outside the United States to diagnose vesicoureteral reflux (VUR) in children and is highly sensitive while avoiding exposure to ionizing radiation. At the onset of this study, two ultrasound (US) contrast agents were available in the United States. Pediatric safety data for intravenous administration was published for one, Optison™. This study aimed to evaluate the diagnostic performance and safety of ceVUS using Optison™ and compare its diagnostic efficacy with voiding cystourethrogram (VCUG) for VUR detection and grading in children. The United States Food and Drug Administration and institutional Investigational New Drug authorizations were obtained to conduct a prospective comparative study of ceVUS with Optison™ and VCUG. CeVUS was performed with intravesical administration of 0.2% Optison™/normal saline solution. A standard VCUG followed. Safety assessment included physical examination, and heart rate, pulse oximetry and adverse reactions monitoring before, during and immediately after the examinations. A follow-up questionnaire was completed by telephone 48-h after the studies. Sixty-two pelviureteric units were studied in 30 patients with a mean age of 3.5 years (range: 0.1-17 years) including 21 girls and 9 boys. No severe adverse events occurred. All patients had normal heart rate and blood oxygenation saturation prior to, during and after the studies. At the 48-h follow-up, one patient (3.3%) reported transient dysuria. Taking the VCUG as the reference standard, ceVUS had a sensitivity of 91.7% (95%; confidence interval [CI]: 61.5%-99.8%) and specificity of 98% (95%; CI: 89.4%-99.9%). The concordance between ceVUS and VCUG for VUR detection and grading was 84.3% and 81.8%, respectively. VUR grades were discrepant in 4/11 refluxing pelviureteric units, with VCUG upgrading VUR in 2. Detection of VUR with Optison™ ceVUS was comparable to VCUG without exposure to ionizing radiation

  13. Contrasting Nephropathic Responses to Oral Administration of Extract of Cultured Penicillium polonicum in Rat and Primate

    Directory of Open Access Journals (Sweden)

    John E. Fincham

    2010-08-01

    Full Text Available Liquid- or solid substrate-cultured Penicillium polonicum administered in feed to rats over several days evokes a histopathological response in kidney involving apoptosis and abnormal mitosis in proximal tubules. The amphoteric toxin is yet only partly characterized, but can be isolated from cultured sporulating biomass in a fraction that is soluble in water and ethanol, and exchangeable on either anion- or cation-exchange resins. After several weeks of treatment renal proximal tubule distortion became striking on account of karyocytomegaly, but even treatment for nearly two years remained asymptomatic. Extract from a batch of solid substrate fermentation of P. polonicum on shredded wheat was incorporated into feed for rats during four consecutive days, and also given as an aqueous solution by oral gavage to a vervet monkey daily for 10 days. Treatment was asymptomatic for both types of animal. Rat response was evident as the typical renal apoptosis and karyomegaly. In contrast there was no such response in the primate; and neither creatinine clearance nor any haematological characteristic or serum component concentration deviated from a control or from historical data for this primate. The contrast is discussed concerning other negative findings for P. polonicum in pigs and hamsters. Renal karyomegaly, as a common rat response to persistent exposure to ochratoxin A, is not known in humans suspected as being exposed to more than the usual trace amounts of dietary ochratoxin A. Therefore the present findings question assumptions that human response to ochratoxin A conforms to that in the rat.

  14. Vascularization of liver tumors - preliminary results with Coded Harmonic Angio (CHA), phase inversion imaging, 3D power Doppler and contrast medium-enhanced B-flow with second generation contrast agent (Optison).

    Science.gov (United States)

    Jung, E M; Kubale, R; Jungius, K-P; Jung, W; Lenhart, M; Clevert, D-A

    2006-01-01

    To investigate the dynamic value of contrast medium-enhanced ultrasonography with Optison for appraisal of the vascularization of hepatic tumors using harmonic imaging, 3D-/power Doppler and B-flow. 60 patients with a mean age of 56 years (range 35-76 years) with 93 liver tumors, including histopathologically proven hepatocellular carcinoma (HCC) [15 cases with 20 lesions], liver metastases of colorectal tumors [17 cases with 33 lesions], metastases of breast cancer [10 cases with 21 lesions] and hemangiomas [10 cases with 19 lesions] were prospectively investigated by means of multislice CT as well as native and contrast medium-enhanced ultrasound using a multifrequency transducer (2.5-4 MHz, Logig 9, GE). B scan was performed with additional color and power Doppler, followed by a bolus injection of 0.5 ml Optison. Tumor vascularization was evaluated with coded harmonic angio (CHA), pulse inversion imaging with power Doppler, 3D power Doppler and in the late phase (>5 min) with B-flow. In 15 cases with HCC, i.a. DSA was performed in addition. The results were also correlated with MRT and histological findings. Compared to spiral-CT/MRT, only 72/93 (77%) of the lesions could be detected in the B scan, 75/93 (81%) with CHA and 93/93 (100%) in the pulse inversion mode. Tumor vascularization was detectable in 43/93 (46%) of lesions with native power Doppler, in 75/93 (81%) of lesions after administering contrast medium in the CHA mode, in 81/93 (87%) of lesions in the pulse inversion mode with power Doppler and in 77/93 (83%) of lesions with contrast-enhanced B-flow. Early arterial and capillary perfusion was best detected with CHA, particularly in 20/20 (100%) of the HCC lesions, allowing a 3D reconstruction. 3D power Doppler was especially useful in investigating the tumor margins. Up to 20 min after contrast medium injection, B-flow was capable of detecting increased metastatic tumor vascularization in 42/54 (78%) of cases and intratumoral perfusion in 17/20 (85

  15. Gadolinium deposition within the dentate nucleus and globus pallidus after repeated administrations of gadolinium-based contrast agents - current status

    Energy Technology Data Exchange (ETDEWEB)

    Stojanov, Dragan [University of Nis, Faculty of Medicine, Nis (Serbia); Center for Radiology, Nis (Serbia); Aracki-Trenkic, Aleksandra [Center for Radiology, Nis (Serbia); Benedeto-Stojanov, Daniela [University of Nis, Faculty of Medicine, Nis (Serbia)

    2016-05-15

    Gadolinium-based contrast agents (GBCAs) have been used clinically since 1988 for contrast-enhanced magnetic resonance imaging (CE-MRI). Generally, GBCAs are considered to have an excellent safety profile. However, GBCA administration has been associated with increased occurrence of nephrogenic systemic fibrosis (NSF) in patients with severely compromised renal function, and several studies have shown evidence of gadolinium deposition in specific brain structures, the globus pallidus and dentate nucleus, in patients with normal renal function. Gadolinium deposition in the brain following repeated CE-MRI scans has been demonstrated in patients using T1-weighted unenhanced MRI and inductively coupled plasma mass spectroscopy. Additionally, rodent studies with controlled GBCA administration also resulted in neural gadolinium deposits. Repeated GBCA use is associated with gadolinium deposition in the brain. This is especially true with the use of less-stable, linear GBCAs. In spite of increasing evidence of gadolinium deposits in the brains of patients after multiple GBCA administrations, the clinical significance of these deposits continues to be unclear. Here, we discuss the current state of scientific evidence surrounding gadolinium deposition in the brain following GBCA use, and the potential clinical significance of gadolinium deposition. There is considerable need for further research, both to understand the mechanism by which gadolinium deposition in the brain occurs and how it affects the patients in which it occurs. (orig.)

  16. Intracavitary application of contrast medium in the follow-up of complicated tube-drained pleural empyema: Conventional radiography vs CT

    International Nuclear Information System (INIS)

    Duex, M.; Bischoff, H.; Schmaehl, A.; Tuengerthal, S.

    1997-01-01

    Purpose: To define the value of conventional radiography compared with CT in the follow-up of complicated, long-term tube drained pleural empyema after intracavitary application of contrast medium. Methods: 28 patients with complicated pleural empyema (stage III) and longterm tube drainage were submitted to fluoroscopy of the pleural cavity and a CT of the thorax after contrast medium had been instilled into the pleural space. Both examinations were judged by the following criteria: Number and morphology of pleural cavities, quality of drainage and accompanying thoracic disease. Results: 49 pleural cavities were diagnosed. Judgement of drainage corresponded in 79% of cases and differed 21% with proof of further not drained cavities only on CT. 4 bronchopleural fistulas were diagnosed by fluoroscopy, of which only 2 were evident on CT. Accompanying thoracic disease was reliably detected by CT only. Conclusions: Diagnosis of bronchopleural fistulas and judgement of the pleural drainage is best possible using fluoroscopy after application of contrast medium into the pleural space. CT is most accurate to detect further cavities that have not been drained, to look for concomitant thoracic disease, and to judge the morphology of the pleural cavity. Conventional radiography of the pleural space is effective and recommended to be used as a first line investigation for the follow-up of stage III empyemas. Patients in poor general condition (fever, elevated blood markers indicating inflammation) should be examined by both fluoroscopy and CT. (orig.) [de

  17. Nonlinear image blending for dual-energy MDCT of the abdomen: can image quality be preserved if the contrast medium dose is reduced?

    Science.gov (United States)

    Mileto, Achille; Ramirez-Giraldo, Juan Carlos; Marin, Daniele; Alfaro-Cordoba, Marcela; Eusemann, Christian D; Scribano, Emanuele; Blandino, Alfredo; Mazziotti, Silvio; Ascenti, Giorgio

    2014-10-01

    The objective of this study was to compare the image quality of a dual-energy nonlinear image blending technique at reduced load of contrast medium with a simulated 120-kVp linear blending technique at a full dose during portal venous phase MDCT of the abdomen. Forty-five patients (25 men, 20 women; mean age, 65.6 ± 9.7 [SD] years; mean body weight, 74.9 ± 12.4 kg) underwent contrast-enhanced single-phase dual-energy CT of the abdomen by a random assignment to one of three different contrast medium (iomeprol 400) dose injection protocols: 1.3, 1.0, or 0.65 mL/kg of body weight. The contrast-to-noise ratio (CNR) and noise at the portal vein, liver, aorta, and kidney were compared among the different datasets using the ANOVA. Three readers qualitatively assessed all datasets in a blinded and independent fashion. Nonlinear blended images at a 25% reduced dose allowed a significant improvement in CNR (p < 0.05 for all comparisons), compared with simulated 120-kVp linear blended images at a full dose. No statistically significant difference existed in CNR and noise between the nonlinear blended images at a 50% reduced dose and the simulated 120-kVp linear blended images at a full dose. Nonlinear blended images at a 50% reduced dose were considered in all cases to have acceptable image quality. The dual-energy nonlinear image blending technique allows reducing the dose of contrast medium up to 50% during portal venous phase imaging of the abdomen while preserving image quality.

  18. Influence of osmolarity of contrast medium and saline flush on computed tomography angiography: Comparison of monomeric and dimeric iodinated contrast media with different iodine concentrations at an identical iodine delivery rate

    International Nuclear Information System (INIS)

    Kishimoto, Miori; Doi, Shoko; Shimizu, Junichiro; Lee, Ki-Ja; Iwasaki, Toshiroh; Miyake, Yoh-Ichi; Yamada, Kazutaka

    2010-01-01

    Purpose: To evaluate the influence of osmolarity of iodinated contrast media and saline flush on the contrast effect in thoracic computed tomography angiography (CTA) at an identical iodine delivery rate (IDR). Materials and methods: Seven beagles were used in a cross-over experiment. The contrast media used were iohexol 350 mgI/ml (IOH350; osmolarity 844 mmol/kg) and iodixanol 320 mgI/ml (IDX320; osmolarity 290 mmol/kg). Each contrast medium was administered to groups with and without saline flush at 40.0 mgI/kg/s for all experiments. Dynamic CT scanning was performed at the ninth thoracic vertebra level. The peak value, area under the curve (AUC), and time to peak (TTP) were calculated from the time attenuation curves of the pulmonary artery and aorta. Results: There was no significant difference between IOH350 and IDX320 with or without saline flush in the peak values for the pulmonary artery and aorta. AUC was significantly higher in groups with saline flush for both contrast media and arteries (p < 0.05) with no significant difference between contrast media. TTP was significantly longer in groups with saline flush than without saline flush for both contrast media and arteries (p < 0.05), with no significant difference between contrast media. Conclusions: There were no significant differences in the contrast effects of monomeric IOH350 and dimeric IDX320 in thoracic CTA when used at an identical IDR. Moreover, saline flush prolonged the peak duration at 600 mgI/kg.

  19. Contrast media administration in coronary computed tomography angiography. A systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Mihl, Casper; Kok, Madeleine; Wildberger, Joachim E.; Das, Marco [Maastricht Univ. Medical Center (Netherlands). CARIM School for Cardiovascular Diseases; Maastricht Univ. Medical Center (Netherlands). Radiology; Maas, Monique; Lobbes, Marc B.I. [Maastricht Univ. Medical Center (Netherlands). Radiology; Turek, Jakub; Seehofnerova, Anna [Maastricht Univ. Medical Center (Netherlands). CARIM School for Cardiovascular Diseases; Leijenaar, Ralph T.H. [GROW School for Oncology and Developmental Biology, Maastricht (Netherlands). Radiation Oncology (MAASTRO)

    2017-04-15

    Various different injection parameters influence enhancement of the coronary arteries. There is no consensus in the literature regarding the optimal contrast media (CM) injection protocol. The aim of this study is to provide an update on the effect of different CM injection parameters on the coronary attenuation in coronary computed tomographic angiography (CCTA). Studies published between January 2001 and May 2014 identified by Pubmed, Embase and MEDLINE were evaluated. Using predefined inclusion criteria and a data extraction form, the content of each eligible study was assessed. Initially, 2551 potential studies were identified. After applying our criteria, 36 studies were found to be eligible. Studies were systematically assessed for quality based on the validated Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-II checklist. Extracted data proved to be heterogeneous and often incomplete. The injection protocol and outcome of the included publications were very diverse and results are difficult to compare. Based on the extracted data, it remains unclear which of the injection parameters is the most important determinant for adequate attenuation. It is likely that one parameter which combines multiple parameters (e.g. IDR) will be the most suitable determinant of coronary attenuation in CCTA protocols. Research should be directed towards determining the influence of different injection parameters and defining individualized optimal IDRs tailored to patient-related factors (ideally in large randomized trials). Key points: This systematic review provides insight into decisive factors on coronary attenuation. Different and contradicting outcomes are reported on coronary attenuation in CCTA. One parameter combining multiple parameters (IDR) is likely decisive in coronary attenuation. Research should aim at defining individualized optimal IDRs tailored to individual factors. Future directions should be tailored towards the influence of different injection

  20. Contrast media administration in coronary computed tomography angiography. A systematic review

    International Nuclear Information System (INIS)

    Mihl, Casper; Kok, Madeleine; Wildberger, Joachim E.; Das, Marco

    2017-01-01

    Various different injection parameters influence enhancement of the coronary arteries. There is no consensus in the literature regarding the optimal contrast media (CM) injection protocol. The aim of this study is to provide an update on the effect of different CM injection parameters on the coronary attenuation in coronary computed tomographic angiography (CCTA). Studies published between January 2001 and May 2014 identified by Pubmed, Embase and MEDLINE were evaluated. Using predefined inclusion criteria and a data extraction form, the content of each eligible study was assessed. Initially, 2551 potential studies were identified. After applying our criteria, 36 studies were found to be eligible. Studies were systematically assessed for quality based on the validated Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-II checklist. Extracted data proved to be heterogeneous and often incomplete. The injection protocol and outcome of the included publications were very diverse and results are difficult to compare. Based on the extracted data, it remains unclear which of the injection parameters is the most important determinant for adequate attenuation. It is likely that one parameter which combines multiple parameters (e.g. IDR) will be the most suitable determinant of coronary attenuation in CCTA protocols. Research should be directed towards determining the influence of different injection parameters and defining individualized optimal IDRs tailored to patient-related factors (ideally in large randomized trials). Key points: This systematic review provides insight into decisive factors on coronary attenuation. Different and contradicting outcomes are reported on coronary attenuation in CCTA. One parameter combining multiple parameters (IDR) is likely decisive in coronary attenuation. Research should aim at defining individualized optimal IDRs tailored to individual factors. Future directions should be tailored towards the influence of different injection

  1. Nephropathy after administration of iso-osmolar and low-osmolar contrast media: evidence from a network meta-analysis.

    Science.gov (United States)

    Biondi-Zoccai, Giuseppe; Lotrionte, Marzia; Thomsen, Henrik S; Romagnoli, Enrico; D'Ascenzo, Fabrizio; Giordano, Arturo; Frati, Giacomo

    2014-03-15

    Contrast-induced nephropathy (CIN) may be a severe complication to the administration of iodine-based contrast media for diagnostic or interventional procedure using radiation exposure. Whether there is a difference in nephrotoxic potential between the various agents is uncertain. We aimed to perform a systematic review and network meta-analysis of randomized trials on iodine-based contrast agents. Randomized trials of low-osmolar or iso-osmolar contrast media were searched in CENTRAL, Google Scholar, MEDLINE/PubMed, and Scopus. Risk of CIN was appraised within a hierarchical Bayesian model computing absolute rates (AR) and odds ratios (OR) with 95% credibility intervals, and probability of being best (Pbest) for each agent. A total of 42 trials (10048 patients) were included focusing on 7 different iodine-based contrast media. Risk of CIN was similarly low with iodixanol (AR=5.7% [2.2%-13.9%], Pbest=18.8%), iomeprol (AR=6.0% [2.2%-15.4%], Pbest=24.8%), iopamidol (AR=6.1% [2.2%-15.5%], Pbest=21.5%), and ioversol (AR=6.0% [2.1%-16.4%], Pbest=31.3%). Conversely, CIN was twice as common with iohexol (AR=11.2% [4.1%-29.5%], Pbest=0.1%) and ioxaglate (AR=11.0% [4.0%-26.9%], Pbestcontrast media with a similar renal safety profile. Iohexol and ioxaglate have a poorer renal safety profile, whereas further data may be required on iopromide. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. Can low-dose CT with iterative reconstruction reduce both the radiation dose and the amount of iodine contrast medium in a dynamic CT study of the liver?

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroto; Okada, Masahiro; Hyodo, Tomoko; Hidaka, Syojiro; Kagawa, Yuki; Matsuki, Mitsuru; Tsurusaki, Masakatsu; Murakami, Takamichi, E-mail: murakami@med.kindai.ac.jp

    2014-04-15

    Purpose: To investigate whether low-dose dynamic CT of the liver with iterative reconstruction can reduce both the radiation dose and the amount of contrast medium. Materials and methods: This study was approved by our institutional review board. 113 patients were randomly assigned to one of two groups. Group A/group B (fifty-eight/fifty-five patients) underwent liver dynamic CT at 120/100 kV, with 0/40% adaptive statistical iterative reconstruction (ASIR), with a contrast dose of 600/480 mg I/kg, respectively. Radiation exposure was estimated based on the manufacturer's phantom data. The enhancement value of the hepatic parenchyma, vessels and the tumor-to-liver contrast of hepatocellular carcinomas (HCCs) were compared between two groups. Two readers independently assessed the CT images of the hepatic parenchyma and HCCs. Results: The mean CT dose indices: 6.38/4.04 mGy, the dose-length products: 194.54/124.57 mGy cm, for group A/group B. The mean enhancement value of the hepatic parenchyma and the tumor-to-liver contrast of HCCs with diameters greater than 1 cm in the post-contrast all phases did not differ significantly between two groups (P > 0.05). The enhancement values of vessels in group B were significantly higher than that in group A in the delayed phases (P < 0.05). Two reader's confidence levels for the hepatic parenchyma in the delayed phases and HCCs did not differ significantly between the groups (P > 0.05). Conclusions: Low-dose dynamic CT with ASIR can reduce both the radiation dose and the amount of contrast medium without image quality degradation, compared to conventional dynamic CT without ASIR.

  3. Role of medium heterogeneity and viscosity contrast in miscible flow regimes and mixing zone growth: A computational pore-scale approach

    Science.gov (United States)

    Afshari, Saied; Hejazi, S. Hossein; Kantzas, Apostolos

    2018-05-01

    Miscible displacement of fluids in porous media is often characterized by the scaling of the mixing zone length with displacement time. Depending on the viscosity contrast of fluids, the scaling law varies between the square root relationship, a sign for dispersive transport regime during stable displacement, and the linear relationship, which represents the viscous fingering regime during an unstable displacement. The presence of heterogeneities in a porous medium significantly affects the scaling behavior of the mixing length as it interacts with the viscosity contrast to control the mixing of fluids in the pore space. In this study, the dynamics of the flow and transport during both unit and adverse viscosity ratio miscible displacements are investigated in heterogeneous packings of circular grains using pore-scale numerical simulations. The pore-scale heterogeneity level is characterized by the variations of the grain diameter and velocity field. The growth of mixing length is employed to identify the nature of the miscible transport regime at different viscosity ratios and heterogeneity levels. It is shown that as the viscosity ratio increases to higher adverse values, the scaling law of mixing length gradually shifts from dispersive to fingering nature up to a certain viscosity ratio and remains almost the same afterwards. In heterogeneous media, the mixing length scaling law is observed to be generally governed by the variations of the velocity field rather than the grain size. Furthermore, the normalization of mixing length temporal plots with respect to the governing parameters of viscosity ratio, heterogeneity, medium length, and medium aspect ratio is performed. The results indicate that mixing length scales exponentially with log-viscosity ratio and grain size standard deviation while the impact of aspect ratio is insignificant. For stable flows, mixing length scales with the square root of medium length, whereas it changes linearly with length during

  4. Haemodynamic-guided fluid administration for the prevention of contrast-induced acute kidney injury: the POSEIDON randomised controlled trial.

    Science.gov (United States)

    Brar, Somjot S; Aharonian, Vicken; Mansukhani, Prakash; Moore, Naing; Shen, Albert Y-J; Jorgensen, Michael; Dua, Aman; Short, Lindsay; Kane, Kevin

    2014-05-24

    The administration of intravenous fluid remains the cornerstone treatment for the prevention of contrast-induced acute kidney injury. However, no well-defined protocols exist to guide fluid administration in this treatment. We aimed to establish the efficacy of a new fluid protocol to prevent contrast-induced acute kidney injury. In this randomised, parallel-group, comparator-controlled, single-blind phase 3 trial, we assessed the efficacy of a new fluid protocol based on the left ventricular end-diastolic pressure for the prevention of contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. The primary outcome was the occurrence of contrast-induced acute kidney injury, which was defined as a greater than 25% or greater than 0·5 mg/dL increase in serum creatinine concentration. Between Oct 10, 2010, and July 17, 2012, 396 patients aged 18 years or older undergoing cardiac catheterisation with an estimated glomerular filtration rate of 60 mL/min per 1·73 m(2) or less and one or more of several risk factors (diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years) were randomly allocated in a 1:1 ratio to left ventricular end-diastolic pressure-guided volume expansion (n=196) or the control group (n=200) who received a standard fluid administration protocol. Four computer-generated concealed randomisation schedules, each with permuted block sizes of 4, were used for randomisation, and participants were allocated to the next sequential randomisation number by sealed opaque envelopes. Patients and laboratory personnel were masked to treatment assignment, but the physicians who did the procedures were not masked. Both groups received intravenous 0·9% sodium chloride at 3 mL/kg for 1 h before cardiac catheterisation. Analyses were by intention to treat. Adverse events were assessed at 30 days and 6 months and all such events were classified by staff who were masked to treatment assignment. This

  5. Evaluation of Tumor Angiogenesis with a Second-Generation US Contrast Medium in a Rat Breast Tumor Model

    International Nuclear Information System (INIS)

    Ko, Eun Young; Lee, Sang Hoon; Kim, Hak Hee; Kim, Sung Moon; Shin, Myung Jin; Kim, Nam Kug; Gong, Gyung Yub

    2008-01-01

    Tumor angiogenesis is an important factor for tumor growth, treatment response and prognosis. Noninvasive imaging methods for the evaluation of tumor angiogenesis have been studied, but a method for the quantification of tumor angiogenesis has not been established. This study was designed to evaluate tumor angiogenesis in a rat breast tumor model by the use of a contrast enhanced ultrasound (US) examination with a second-generation US contrast agent. The alkylating agent 19N-ethyl-N-nitrosourea (ENU) was injected into the intraperitoneal cavity of 30-day-old female Sprague-Dawley rats. Three to four months later, breast tumors were detected along the mammary lines of the rats. A total of 17 breast tumors larger than 1 cm in nine rats were evaluated by gray-scale US, color Doppler US and contrast-enhanced US using SonoVue. The results were recorded as digital video images; time-intensity curves and hemodynamic parameters were analyzed. Pathological breast tumor specimens were obtained just after the US examinations. The tumor specimens were stained with hematoxylin and eosin (H and E) and the expression of CD31, an endothelial cell marker, was determined by immunohistochemical staining. We also evaluated the pathological diagnosis of the tumors and the microvessel density (MVD). Spearman's correlation and the Kruskal-Wallis test were used for the analysis. The pathological diagnoses were 11 invasive ductal carcinomas and six benign intraductal epithelial proliferations. The MVD did not correlate with the pathological diagnosis. However, blood volume (BV) showed a statistically significant correlation with MVD (Spearman's correlation, p < 0.05). Contrast-enhanced US using a second-generation US contrast material was useful for the evaluation of tumor angiogenesis of breast tumors in the rat

  6. Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning

    Energy Technology Data Exchange (ETDEWEB)

    Felmly, Lloyd M. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiothoracic Surgery, Department of Surgery, Charleston, SC (United States); De Cecco, Carlo N.; Varga-Szemes, Akos; McQuiston, Andrew D. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U.J.; Litwin, Sheldon E.; Bayer, Richard R. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Vogl, Thomas J. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany)

    2017-05-15

    To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR). Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured. Besides a higher body-mass-index in group B (24.8±3.8 kg/m{sup 2} vs. 28.1±5.4 kg/m{sup 2}, P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302). TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition. (orig.)

  7. Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning

    International Nuclear Information System (INIS)

    Felmly, Lloyd M.; De Cecco, Carlo N.; Varga-Szemes, Akos; McQuiston, Andrew D.; Schoepf, U.J.; Litwin, Sheldon E.; Bayer, Richard R.; Mangold, Stefanie; Vogl, Thomas J.; Wichmann, Julian L.

    2017-01-01

    To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR). Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured. Besides a higher body-mass-index in group B (24.8±3.8 kg/m 2 vs. 28.1±5.4 kg/m 2 , P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302). TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition. (orig.)

  8. Oral administration of a medium containing both D-aspartate-producing live bacteria and D-aspartate reduces rectal temperature in chicks.

    Science.gov (United States)

    Do, P H; Tran, P V; Bahry, M A; Yang, H; Han, G; Tsuchiya, A; Asami, Y; Furuse, M; Chowdhury, V S

    2017-10-01

    1. The aim of this study was to investigate the effects on the rectal temperature of young chicks of the oral administration of a medium that contained both live bacteria that produce D-aspartate (D-Asp) and D-Asp. 2. In Experiment 1, chicks were subjected to chronic oral administration of either the medium (containing live bacteria and 2.46 μmol D-Asp) or water from 7 to 14 d of age. Plasma-free amino acids as well as mitochondrial biogenic gene expression in the breast muscle were analysed. In Experiment 2, 7-d-old chicks were subjected to acute oral administration of the above medium or of an equimolar amount of D-Asp to examine their effect on changes in rectal temperature. In Experiment 3, after 1 week of chronic oral administration of the medium, 14-d-old chicks were exposed to either high ambient temperature (HT; 40 ± 1°C, 3 h) or control thermoneutral temperature (CT; 30 ± 1°C, 3 h) to monitor the changes in rectal temperature. 3. Chronic, but not acute, oral administration of the medium significantly reduced rectal temperature in chicks, and a chronic effect also appeared under HT conditions. 4. Chronic oral administration of the medium significantly reduced the mRNA abundance of the avian uncoupling protein (avUCP) in the breast muscle, but led to a significant increase in avian adenine nucleotide translocator (avANT) mRNA in the same muscle. 5. (a) These results indicate that the medium can reduce body temperature through the decline in avUCP mRNA expression in the breast muscle that may be involved in reduced mitochondrial proton leaks and heat production. (b) The increase in avANT further suggests a possible enhancement of adenosine triphosphate (ATP) synthesis.

  9. Barium sulfate aspiration: Severe chemical pneumonia induced by a massive reflux of contrast medium during small bowel barium enema.

    Science.gov (United States)

    Zhang, Lin; Yang, Yi; Zhang, Ji; Zhou, Xiaowei; Dong, Hongmei; Zhou, Yiwu

    2015-08-01

    Barium contrast radiography is a conventional procedure aimed at revealing lesions of the alimentary tract using barium sulfate on X-ray irradiation. Although it is widely used in clinics, adverse effects and complications are observed, such as anaphylaxis, granuloma, fecalithes, abdomen-leaking, embolism, bacterial contamination, and aspiration. We report a case of death due to a massive barium sulfate aspiration resulted from an air-barium double contrast enema radiography. A 25-year-old female patient was hospitalized with symptoms of abdominal distention, nausea, vomiting and diarrhea for three days. A progressive respiratory distress presented only 1h after a small bowel air-barium double contrast enema. The patient died 11h later. The result of autopsy revealed the cause of death to be severe chemical pneumonitis induced by gastric fluid which was aspirated into her lungs. Barium sulfate is generally recognized to be chemically inert for the respiratory system, but a mixture of barium sulfate with gastric contents is fatal. Here we intend to suggest that, when determining the potential cause of death, medical examiners should consider a patient's status quo as well as the possible adverse effects and complications caused by the barium sulfate preparation during gastrointestinal radiography. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. The role of dual energy CT in differentiating between brain haemorrhage and contrast medium after mechanical revascularisation in acute ischaemic stroke

    International Nuclear Information System (INIS)

    Tijssen, M.P.M.; Stadler, A.A.R.; Zwam, W. van; Graaf, R. de; Postma, A.A.; Hofman, P.A.M.; Oostenbrugge, R.J. van; Klotz, E.; Wildberger, J.E.

    2014-01-01

    To assess the feasibility of dual energy computed tomography (DE-CT) in intra-arterially treated acute ischaemic stroke patients to discriminate between contrast extravasation and intracerebral haemorrhage. Thirty consecutive acute ischaemic stroke patients following intra-arterial treatment were examined with DE-CT. Simultaneous imaging at 80 kV and 140 kV was employed with calculation of mixed images. Virtual unenhanced non-contrast (VNC) images and iodine overlay maps (IOM) were calculated using a dedicated brain haemorrhage algorithm. Mixed images alone, as ''conventional CT'', and DE-CT interpretations were evaluated and compared with follow-up CT. Eight patients were excluded owing to a lack of follow-up or loss of data. Mixed images showed intracerebral hyperdense areas in 19/22 patients. Both haemorrhage and residual contrast material were present in 1/22. IOM suggested contrast extravasation in 18/22 patients; in 16/18 patients this was confirmed at follow-up. The positive predictive value (PPV) of mixed imaging alone was 25 %, with a negative predictive value (NPV) of 91 % and accuracy of 63 %. The PPV for detection of haemorrhage with DE-CT was 100 %, with an NPV of 89 % and accuracy improved to 89 %. Dual energy computed tomography improves accuracy and diagnostic confidence in early differentiation between intracranial haemorrhage and contrast medium extravasation in acute stroke patients following intra-arterial revascularisation. (orig.)

  11. The role of dual energy CT in differentiating between brain haemorrhage and contrast medium after mechanical revascularisation in acute ischaemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Tijssen, M.P.M.; Stadler, A.A.R.; Zwam, W. van; Graaf, R. de; Postma, A.A. [Maastricht University Medical Centre, Department of Radiology, P.O. Box 5800, Maastricht (Netherlands); Hofman, P.A.M. [Maastricht University Medical Centre, Department of Radiology, P.O. Box 5800, Maastricht (Netherlands); Maastricht University, MhENS School for Mental Health and Neuroscience, Maastricht (Netherlands); Oostenbrugge, R.J. van [Maastricht University Medical Centre, Department of Neurology, P.O. Box 5800, Maastricht (Netherlands); Maastricht University, CARIM School for Cardiovascular Diseases, P.O. Box 616, Maastricht (Netherlands); Klotz, E. [Siemens Healthcare Sector, Computed Tomography, Forchheim (Germany); Wildberger, J.E. [Maastricht University Medical Centre, Department of Radiology, P.O. Box 5800, Maastricht (Netherlands); Maastricht University, CARIM School for Cardiovascular Diseases, P.O. Box 616, Maastricht (Netherlands)

    2014-04-15

    To assess the feasibility of dual energy computed tomography (DE-CT) in intra-arterially treated acute ischaemic stroke patients to discriminate between contrast extravasation and intracerebral haemorrhage. Thirty consecutive acute ischaemic stroke patients following intra-arterial treatment were examined with DE-CT. Simultaneous imaging at 80 kV and 140 kV was employed with calculation of mixed images. Virtual unenhanced non-contrast (VNC) images and iodine overlay maps (IOM) were calculated using a dedicated brain haemorrhage algorithm. Mixed images alone, as ''conventional CT'', and DE-CT interpretations were evaluated and compared with follow-up CT. Eight patients were excluded owing to a lack of follow-up or loss of data. Mixed images showed intracerebral hyperdense areas in 19/22 patients. Both haemorrhage and residual contrast material were present in 1/22. IOM suggested contrast extravasation in 18/22 patients; in 16/18 patients this was confirmed at follow-up. The positive predictive value (PPV) of mixed imaging alone was 25 %, with a negative predictive value (NPV) of 91 % and accuracy of 63 %. The PPV for detection of haemorrhage with DE-CT was 100 %, with an NPV of 89 % and accuracy improved to 89 %. Dual energy computed tomography improves accuracy and diagnostic confidence in early differentiation between intracranial haemorrhage and contrast medium extravasation in acute stroke patients following intra-arterial revascularisation. (orig.)

  12. Ultrastructural study on the effects of retrograde infusion of water-soluble contrast medium the rabbit submandibular gland

    International Nuclear Information System (INIS)

    Kim, Eun Kyung; Park, Tae Won

    1987-01-01

    The author observed the effects of retrograde infusion of water soluble contrast media (Telebrix 30) on the rabbit submandibular glands and compared the effects of different degrees of filling. 26 rabbit were divided into 2 group of 1 2 each as experimental and 1 group of 2 as normal controls. One experimental group was filed with 0.2 ml and the other with 0.4 ml. Right submandibular gland of each rabbit was infused with contrast media and left one with physiologic saline as a ex perimental control, at a constant rate of 0.12 ml/min. Using an infusion pump via the main excretory duct. Immediately after the inclusion of contrast media, oblique lateral radiographs of the glands were made with occlusal film in order to confirm the glandular filling. The rabbit were sacrificed after varying periods (1, 8, 24 hours and 3, 6, 10 days) and the tissues were prepared for light and electron microscopic examination. The results were as follows: 1. In glands filled with 0.2 ml contrast media, the initial changes were a few vacuole formation in the acini and slight dilation of the intralobular duct. The moderately severe changes such as vacuole formation in the acini, the abnormal substructure within the secretory granule, dilation of acinar and intercalated duct lumen, scalloping of striated duct lumen and inflammatory cell infiltrate were observed at 3 days. The general appearance was successively recovered, so the tissue had a normal appearance at 10 days. 2. In glands filled with 0.4 ml contrast media, the most prominent alterations such as severe acinar atrophy, decreased number of secretory granules, proliferation of connective tissue stroma and pronounced inflammatory cell infiltrates appeared at 6 days. Although the general appearance returned to be almost normal at 10 days, acinar cells showed some atrophy and decreased secretory granules. 3. In glands subjected to 0.4 ml infusion, the alterations were more severe and recovery was slower than those seen in the glands

  13. 3D CT cerebral angiography technique using a 320-detector machine with a time–density curve and low contrast medium volume: Comparison with fixed time delay technique

    International Nuclear Information System (INIS)

    Das, K.; Biswas, S.; Roughley, S.; Bhojak, M.; Niven, S.

    2014-01-01

    Aim: To describe a cerebral computed tomography angiography (CTA) technique using a 320-detector CT machine and a small contrast medium volume (35 ml, 15 ml for test bolus). Also, to compare the quality of these images with that of the images acquired using a larger contrast medium volume (90 or 120 ml) and a fixed time delay (FTD) of 18 s using a 16-detector CT machine. Materials and methods: Cerebral CTA images were acquired using a 320-detector machine by synchronizing the scanning time with the time of peak enhancement as determined from the time–density curve (TDC) using a test bolus dose. The quality of CTA images acquired using this technique was compared with that obtained using a FTD of 18 s (by 16-detector CT), retrospectively. Average densities in four different intracranial arteries, overall opacification of arteries, and the degree of venous contamination were graded and compared. Results: Thirty-eight patients were scanned using the TDC technique and 40 patients using the FTD technique. The arterial densities achieved by the TDC technique were higher (significant for supraclinoid and basilar arteries, p < 0.05). The proportion of images deemed as having “good” arterial opacification was 95% for TDC and 90% for FTD. The degree of venous contamination was significantly higher in images produced by the FTD technique (p < 0.001%). Conclusion: Good diagnostic quality CTA images with significant reduction of venous contamination can be achieved with a low contrast medium dose using a 320-detector machine by coupling the time of data acquisition with the time of peak enhancement

  14. Does the MRI or MRI contrast medium gadopentetate dimeglumine change the oxidant and antioxidant status in humans?

    Energy Technology Data Exchange (ETDEWEB)

    Olmaz, Refik; Oguz, Ebru Gok; Kiykim, Ahmet; Turgutalp, Kenan [Dept. of Internal Medicine, Div. of Nephrology, School of Medicine, Mersin Univ., Mersin (Turkey)], e-mail: k.turgutalp@hotmail.com; Horoz, M. [Dept. of Internal Medicine, Div. of Nephrology, School of Medicine, Harran Univ., Sanliurfa (Turkey); Ozhan, Onur [Dept. of Internal Medicine, Div. of Endocrinology and Metabolism, School of Medicine, Mersin Univ., Mersin (Turkey); Muslu, Necati [Dept. of Biochemistry, School of Medicine, Mersin Univ., Mersin (Turkey); Sungur, Mehmet [Dept. of Biostatistics, School of Medicine, Mersin Univ., Mersin (Turkey)

    2013-02-15

    Background: It has become evident that gadolinium-based contrast agents (GBCA) may have nephrotoxic potential. Oxidative stress is one of the most important pathways in the pathogenesis of iodinated contrast-induced nephropathy. Purpose: To investigate the effects of static magnetic fields and gadopentetate dimeglumine (Magnevist) on oxidant/antioxidant status via measurement of total antioxidant capacity (TAC), total oxidant status (TOS), and serum malondialdehide (MDA). Material and Methods: Two age- and sex-matched groups of patients not under oxidative stress conditions that underwent magnetic resonance imaging (MRI) were recruited to this study. While contrast-enhanced (Magnevist, 0.2 mmol/kg) MRI was performed in group 1, MRI without GBCA was performed in group 2. Fasting blood glucose, C-reactive protein, serum creatinine, liver enzymes, uric acid, and lipid parameters were examined in all patients. Peripheral venous blood samples in order to determine TAC, TOS, and MDA were collected before and 6, 24, and 72 h after the MRI procedures. The TOS:TAC ratio was used as the oxidative stress index (OSI). Patients were followed up to 72 h. Results: There were no significant changes in serum TAC, TOS, and MDA levels ({Delta}{sub s}erum{sub T}AC, {Delta}{sub s}erum{sub T}OS, and {Delta}{sub M}DA) in either group 6, 24, or 72 h after the procedures (P > 0.05). Furthermore, OSI did not change after the procedures in either group (P > 0.05). Conclusion: Magnetic field and gadopentetate dimeglumine (Magnevist) do not change the oxidant or antioxidant status at a dose of 0.2 mmol/kg.

  15. Pre-Interventional Kynurenine Predicts Medium-Term Outcome after Contrast Media Exposure Due to Coronary Angiography.

    Science.gov (United States)

    Reichetzeder, Christoph; Heunisch, Fabian; Einem, Gina von; Tsuprykov, Oleg; Kellner, Karl-Heinz; Dschietzig, Thomas; Kretschmer, Axel; Hocher, Berthold

    2017-01-01

    Contrast induced acute kidney injury (CI-AKI) remains a serious complication of contrast media enhanced procedures like coronary angiography. There is still a lack of established biomarkers that help to identify patients at high risk for short and long-term complications. The aim of the current study was to evaluate plasma kynurenine as a predictive biomarker for CI-AKI and long-term complications, measured by the combined endpoint "major adverse kidney events" (MAKE) up to 120 days after CM application. In this prospective cohort study 245 patients undergoing coronary angiography were analyzed. Blood samples were obtained at baseline, 24h and 48h after contrast media (CM) application to diagnose CI-AKI. Patients were followed for 120 days for adverse clinical events including death, the need for dialysis, and a doubling of plasma creatinine. Occurrence of any of these events was summarized in the combined endpoint MAKE. Preinterventional plasma kynurenine was not associated with CI-AKI. Patients who later developed MAKE displayed significantly increased preinterventional plasma kynurenine levels (p<0.0001). ROC analysis revealed that preinterventional kynurenine is highly predictive for MAKE (AUC=0.838; p<0.0001). The optimal cutoff was found at ≥3.5 µmol/L Using this cutoff, the Kaplan-Meier estimator demonstrated that concentrations of plasma kynurenine ≥3.5 µmol/L were significantly associated with a higher prevalence of MAKE until follow up (p<0.0001). This association remained significant in multivariate Cox regression models adjusted for relevant factors of long-term renal outcome. Preinterventional plasma kynurenine might serve as a highly predictive biomarker for MAKE up to 120 days after coronary angiography. © 2017 The Author(s). Published by S. Karger AG, Basel.

  16. Does the MRI or MRI contrast medium gadopentetate dimeglumine change the oxidant and antioxidant status in humans?

    International Nuclear Information System (INIS)

    Olmaz, Refik; Oguz, Ebru Gok; Kiykim, Ahmet; Turgutalp, Kenan; Horoz, M.; Ozhan, Onur; Muslu, Necati; Sungur, Mehmet

    2013-01-01

    Background: It has become evident that gadolinium-based contrast agents (GBCA) may have nephrotoxic potential. Oxidative stress is one of the most important pathways in the pathogenesis of iodinated contrast-induced nephropathy. Purpose: To investigate the effects of static magnetic fields and gadopentetate dimeglumine (Magnevist) on oxidant/antioxidant status via measurement of total antioxidant capacity (TAC), total oxidant status (TOS), and serum malondialdehide (MDA). Material and Methods: Two age- and sex-matched groups of patients not under oxidative stress conditions that underwent magnetic resonance imaging (MRI) were recruited to this study. While contrast-enhanced (Magnevist, 0.2 mmol/kg) MRI was performed in group 1, MRI without GBCA was performed in group 2. Fasting blood glucose, C-reactive protein, serum creatinine, liver enzymes, uric acid, and lipid parameters were examined in all patients. Peripheral venous blood samples in order to determine TAC, TOS, and MDA were collected before and 6, 24, and 72 h after the MRI procedures. The TOS:TAC ratio was used as the oxidative stress index (OSI). Patients were followed up to 72 h. Results: There were no significant changes in serum TAC, TOS, and MDA levels (Δ s erum T AC, Δ s erum T OS, and Δ M DA) in either group 6, 24, or 72 h after the procedures (P > 0.05). Furthermore, OSI did not change after the procedures in either group (P > 0.05). Conclusion: Magnetic field and gadopentetate dimeglumine (Magnevist) do not change the oxidant or antioxidant status at a dose of 0.2 mmol/kg

  17. Pre-Interventional Kynurenine Predicts Medium-Term Outcome after Contrast Media Exposure Due to Coronary Angiography

    Directory of Open Access Journals (Sweden)

    Christoph Reichetzeder

    2017-05-01

    Full Text Available Background/Aims: Contrast induced acute kidney injury (CI-AKI remains a serious complication of contrast media enhanced procedures like coronary angiography. There is still a lack of established biomarkers that help to identify patients at high risk for short and long-term complications. The aim of the current study was to evaluate plasma kynurenine as a predictive biomarker for CI-AKI and long-term complications, measured by the combined endpoint "major adverse kidney events" (MAKE up to 120 days after CM application. Methods: In this prospective cohort study 245 patients undergoing coronary angiography were analyzed. Blood samples were obtained at baseline, 24h and 48h after contrast media (CM application to diagnose CI-AKI. Patients were followed for 120 days for adverse clinical events including death, the need for dialysis, and a doubling of plasma creatinine. Occurrence of any of these events was summarized in the combined endpoint MAKE. Results: Preinterventional plasma kynurenine was not associated with CI-AKI. Patients who later developed MAKE displayed significantly increased preinterventional plasma kynurenine levels (p<0.0001. ROC analysis revealed that preinterventional kynurenine is highly predictive for MAKE (AUC=0.838; p<0.0001. The optimal cutoff was found at ≥3.5 µmol/L Using this cutoff, the Kaplan-Meier estimator demonstrated that concentrations of plasma kynurenine ≥3.5 µmol/L were significantly associated with a higher prevalence of MAKE until follow up (p<0.0001. This association remained significant in multivariate Cox regression models adjusted for relevant factors of long-term renal outcome. Conclusion: Preinterventional plasma kynurenine might serve as a highly predictive biomarker for MAKE up to 120 days after coronary angiography.

  18. Minimizing Contrast Medium Doses to Diagnose Pulmonary Embolism with 80-kVp Multidetector Computed Tomography in Azotemic Patients

    Energy Technology Data Exchange (ETDEWEB)

    Holmquist, F. (Dept. of Diagnostic Radiology, Malmoe Univ. Hospital, Univ. of Lund, Malmoe (Sweden)); Hansson, K.; Pasquariello, F. (Dept. of Internal Medicine, Lasarettet Trelleborg, Univ. of Lund, Trelleborg (Sweden)); Bjoerk, J. (Competence Center for Clinical Research, Univ. Hospital, Univ. of Lund, Lund (Sweden)); Nyman, U. (Dept. of Radiology, Lasarettet Trelleborg, Univ. of Lund, Trelleborg (Sweden))

    2009-02-15

    Background: In diagnosing acute pulmonary embolism (PE) in azotemic patients, scintigraphy and magnetic resonance imaging are frequently inconclusive or not available in many hospitals. Computed tomography is readily available, but relatively high doses (30-50 g I) of potentially nephrotoxic iodine contrast media (CM) are used. Purpose: To report on the diagnostic quality and possible contrast-induced nephropathy (CIN) after substantially reduced CM doses to diagnose PE in azotemic patients using 80-peak kilovoltage (kVp) 16-row multidetector computed tomography (MDCT) combined with CM doses tailored to body weight, fixed injection duration adapted to scan time, automatic bolus tracking, and saline chaser. Material and Methods: Patients with estimated glomerular filtration rate (eGFR) <50 ml/min were scheduled to undergo 80-kVp MDCT using 200 mg I/kg, and those with eGFR =50 ml/min, 120-kVp MDCT with 320 mg I/kg. Both protocols used an 80-kg maximum dose weight and a fixed 15-s injection time. Pulmonary artery density and contrast-to-noise ratio were measured assuming 70 Hounsfield units (HU) for a fresh clot. CIN was defined as a plasma creatinine rise >44.2 mumol/l from baseline. Results: 89/148 patients (63/68 females) underwent 80-/120-kVp protocols, respectively, with 95% of the examinations being subjectively excellent or adequate. Mean values in the 80-/120-kVp cohorts regarding age were 82/65 years, body weight 66/78 kg, effective mAs 277/117, CM dose 13/23 g I, pulmonary artery density 359/345 HU, image noise (1 standard deviation) 24/21 HU, contrast-to-noise ratio 13/13, and dose-length product 173/258 mGycm. Only 1/65 and 2/119 patients in the 80- and 120-kVp cohorts, respectively, with negative CT and no anticoagulation suffered non-fatal thromboembolism during 3-month follow-up. No patient developed CIN. Conclusion: 80-kVp 16-row MDCT with optimization of injection parameters may be performed with preserved diagnostic quality, using markedly reduced CM

  19. Myelography in achondroplasia: value of a lateral C1-2 puncture and non-ionic, water-soluble contrast medium

    International Nuclear Information System (INIS)

    Suss, R.A.; Udvarhelyi, G.B.; Wang, H.; Kumar, A.J.; Zinreich, S.J.; Rosenbaum, A.E.

    1983-01-01

    Because of technical difficulties and diagnostic limitations encountered with other myelographic techniques in patients with achondroplasia, the authors employed a lateral C1-2 puncture and non-ionic, water-soluble contrast medium in 18 achondroplastic patients with spinal compression (21 procedures). This technique proved most appropriate for identifying the upper limit of degenerative osteophytes causing exacerbation of congenital spinal stenosis, which is crucial in planning decompressive surgery. A potentially important additional finding was the presence of degenerative lower cervical spine disease in the majority of patients. There were no serious complications. The authors recommend this technique as safe and effective in achondroplastic patients with severe congenital spinal stenosis

  20. Nephrogenic systemic fibrosis and class labeling of gadolinium-based contrast agents by the Food and Drug Administration.

    Science.gov (United States)

    Yang, Lucie; Krefting, Ira; Gorovets, Alex; Marzella, Louis; Kaiser, James; Boucher, Robert; Rieves, Dwaine

    2012-10-01

    In 2007, the Food and Drug Administration requested that manufacturers of all approved gadolinium-based contrast agents (GBCAs), drugs widely used in magnetic resonance imaging, use nearly identical text in their product labeling to describe the risk of nephrogenic systemic fibrosis (NSF). Accumulating information about NSF risks led to revision of the labeling text for all of these drugs in 2010. The present report summarizes the basis and purpose of this class-labeling approach and describes some of the related challenges, given the evolutionary nature of the NSF risk evidence. The class-labeling approach for presentation of product risk is designed to decrease the occurrence of NSF and to enhance the safe use of GBCAs in radiologic practice. © RSNA, 2012.

  1. Experimental irradiation of the rat ureter: The effects of field size and the presence of contrast medium on incidence and latency of hydronephrosis

    International Nuclear Information System (INIS)

    Knowles, J.F.; Trott, K.R.

    1987-01-01

    Following X-irradiation of a 1.5 cm length of rat ureter, hydronephrosis developed after doses down to 10 Gy. The estimated ED 50 was 11.8 Gy. In the dose range 37.4 Gy to 17.5 Gy there was a significant increase in latency with decreasing dose, but at lower doses the latency did not increase further. Reducing the length of ureter irradiated to 0.5 cm or 0.8 cm caused a decrease in incidence of hydronephrosis and longer latency periods. The ED 50 for rats iradiated to 0.5 cm of ureter was 29.6 Gy. The possibility that secondary radiation produced as a result of interaction between X-radiation and iodinated contrast medium might affect the radiation induction of hydronephrosis was investigated. No difference was found between groups of rats irradiated with or without injection of contrast media. 39 refs.; 4 figs

  2. Long-term retention of gadolinium in the skin of rodents following the administration of gadolinium-based contrast agents

    International Nuclear Information System (INIS)

    Pietsch, Hubertus; Jost, Gregor; Frenzel, Thomas; Huetter, Joachim; Sieber, Martin A.; Lengsfeld, Philipp

    2009-01-01

    Several publications suggest a potential association between the administration of Gadolinium-based contrast agents (GBCAs) and the onset of a rare but serious disease, Nephrogenic Systemic Fibrosis (NSF). The aim of this study was to determine the elimination time-course of Gadolinium (Gd) from skin tissue after application of GBCAs in rats. Seven different marketed GBCAs were injected on five consecutive days at a dose of 2.5 mmol/kg bodyweight into the tail vein of Han-Wistar rats and the Gd concentrations were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) in skin biopsies taken at various time-points up to a year after the last injection. Most of the administered Gd was eliminated from the skin within a time-period of about 2 months. However, the repeated administration of linear GBCAs resulted in long-term retention of a small portion of the administered Gd in the skin tissue of rats, with substantially higher values observed in animals treated with non-ionic linear agents than in those that received ionic linear GBCAs. Following treatment with macrocyclic GBCAs, Gd values in the skin were in the same range as observed in the controls from day 24 post-injection onwards. In summary, we observed a correlation between the complex stability of GBCAs and the amount of residual Gd in the skin up to a year after application of GBCAs. (orig.)

  3. Long-term retention of gadolinium in the skin of rodents following the administration of gadolinium-based contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Pietsch, Hubertus; Jost, Gregor; Frenzel, Thomas; Huetter, Joachim; Sieber, Martin A. [Media Research, Bayer Schering Pharma AG Contrast, Berlin (Germany); Lengsfeld, Philipp [Bayer Schering Pharma AG, Global Medical Affairs Diagnostic Imaging, Berlin (Germany)

    2009-06-15

    Several publications suggest a potential association between the administration of Gadolinium-based contrast agents (GBCAs) and the onset of a rare but serious disease, Nephrogenic Systemic Fibrosis (NSF). The aim of this study was to determine the elimination time-course of Gadolinium (Gd) from skin tissue after application of GBCAs in rats. Seven different marketed GBCAs were injected on five consecutive days at a dose of 2.5 mmol/kg bodyweight into the tail vein of Han-Wistar rats and the Gd concentrations were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) in skin biopsies taken at various time-points up to a year after the last injection. Most of the administered Gd was eliminated from the skin within a time-period of about 2 months. However, the repeated administration of linear GBCAs resulted in long-term retention of a small portion of the administered Gd in the skin tissue of rats, with substantially higher values observed in animals treated with non-ionic linear agents than in those that received ionic linear GBCAs. Following treatment with macrocyclic GBCAs, Gd values in the skin were in the same range as observed in the controls from day 24 post-injection onwards. In summary, we observed a correlation between the complex stability of GBCAs and the amount of residual Gd in the skin up to a year after application of GBCAs. (orig.)

  4. Reducing the risk of iodine-based and MRI contrast media administration: Recommendation for a questionnaire at the time of booking

    International Nuclear Information System (INIS)

    Morcos, Sameh K.; Bellin, Marie-France; Thomsen, Henrik S.; Almen, Torsten; Aspelin, Peter; Heinz-Peer, Gertraud; Jakobsen, Jarl A.; Liss, Per; Oyen, Raymond; Stacul, Fulvio; Molen, Aart J. van der; Webb, Judith A.W.

    2008-01-01

    This paper presents a practical questionnaire to be used when a contrast medium examination is requested. The questionnaire is based on the guidelines from the European Society of Urogenital Radiology. Its aim is to identify patients at increased risk of clinically relevant renal and non-renal adverse reactions to iodine-based and MRI contrast agents. The questionnaire should be completed by the referring physician when the examination is requested

  5. Reducing the risk of iodine-based and MRI contrast media administration: Recommendation for a questionnaire at the time of booking

    Energy Technology Data Exchange (ETDEWEB)

    Morcos, Sameh K. [Department of Diagn. Imaging, Northern General Hospital, Herries Road, Sheffield S5 7AU (United Kingdom)], E-mail: sameh.morcos@sth.nhs.uk; Bellin, Marie-France [Service de Radiologie, Hopital Paul Brousse, 14 Av. Paul Vaillant Couturier, F-94800 Villejuif (France)], E-mail: marie-france.bellin@pbr.ap-hop-paris.fr; Thomsen, Henrik S. [Department of Diagnostic Radiology 54E2, Copenhagen University Hospital Herlev, Herlev Ringvej 75, DK-2730 Herlev (Denmark)], E-mail: hentho01@heh.regionh.dk; Almen, Torsten [Lybska Vaegen 10, S-239 40 Falsterbo (Sweden)], E-mail: torsten.almen@ta-contrast.se; Aspelin, Peter [Diagnostic Radiology, Huddinge University Hospital, S-141 86 Huddinge (Sweden)], E-mail: peter.aspelin@ki.se; Heinz-Peer, Gertraud [Department of Radiology, University Hospital Vienna, AKH, Wahringer Gurtel 18-20, A-1090 Vienna (Austria)], E-mail: gertraud.heinz@meduniwien.ac.at; Jakobsen, Jarl A. [Department of Radiology, Rikshospitalet, N-0027 Oslo (Norway)], E-mail: jarl.jakobsen@rikshospitalet.no; Liss, Per [Department of Radiology, Akademiska sjukhuset, SE-751 85 Uppsala (Sweden)], E-mail: per.liss@akademiska.se; Oyen, Raymond [Department of Radiology, University Hospital Gasthuisberg, Herestraat 46, B-3000 Leuven (Belgium)], E-mail: raymond.oyen@uzleuven.be; Stacul, Fulvio [Institute of Radiology, Ospedale di Cattinara, I-34149 Trieste (Italy)], E-mail: fulvio.stacul@aots.sanita.fvg.it; Molen, Aart J. van der [Department of Radiology, C2-S, Leiden University Medical center, P.O. Box 9600, NL-2300 RC Leiden (Netherlands)], E-mail: aart.vdmolen@planet.nl; Webb, Judith A.W. [3 Sellars Hall Close, Finchley, London N3 1JL (United Kingdom)], E-mail: jawwebb@btopenworld.com

    2008-05-15

    This paper presents a practical questionnaire to be used when a contrast medium examination is requested. The questionnaire is based on the guidelines from the European Society of Urogenital Radiology. Its aim is to identify patients at increased risk of clinically relevant renal and non-renal adverse reactions to iodine-based and MRI contrast agents. The questionnaire should be completed by the referring physician when the examination is requested.

  6. Use of postmortem coronary computed tomography angiography with water-insoluble contrast medium to detect stenosis of the left anterior descending artery in a case of sudden death.

    Science.gov (United States)

    Takahashi, Yoichiro; Sano, Rie; Takahashi, Keiko; Kominato, Yoshihiko; Takei, Hiroyuki; Kobayashi, Susumu; Shimada, Takehiro; Tokue, Hiroyuki; Awata, Sachiko; Hirasawa, Satoshi

    2016-03-01

    A 40-year-old man was found dead on a sidewalk in an expressway parking area one hour after he had entered the area on a motorcycle. A medicolegal autopsy was performed to reveal the cause of this sudden and unexpected death. Postmortem coronary CT angiography after introduction of 5% gelatin-barium emulsion as a radiopaque contrast medium into the heart demonstrated a significant arterial luminal filling defect in the left anterior descending (LAD) coronary artery. Macroscopic and microscopic examinations revealed that a thrombus had become deposited on ruptured plaque within the LAD artery, and that a small amount of the contrast medium was present between the thrombus and the vessel endothelium. These histological findings were consistent with incomplete occlusion of the LAD artery in the 3D reconstructed image. The cause of death in this case was definitively determined to be ischemic heart disease. Postmortem angiography played a role in screening of a vascular lesion that was subsequently verified by histology to have been responsible for sudden and unexpected death. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Automatic individualized contrast medium dosage during hepatic computed tomography by using computed tomography dose index volume (CTDI{sub vol})

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Anders; Cederlund, Kerstin; Aspelin, Peter; Brismar, Torkel B. [Intervention and Technology at Karolinska Institutet, Department of Clinical Science, Division of Medical Imaging and Technology, Stockholm (Sweden); Karolinska University Hospital in Huddinge, Department of Radiology, Stockholm (Sweden); Bjoerk, Jonas [FoU-centrum Skaane Skaanes Universitetssjukhus i Lund, Lund (Sweden); Nyman, Ulf [University of Lund, Department of Diagnostic Radiology, Lasarettet Trelleborg, Trelleborg (Sweden)

    2014-08-15

    To compare hepatic parenchymal contrast media (CM) enhancement during multi-detector row computed tomography (MDCT) and its correlation with volume pitch-corrected computed tomography dose index (CTDI{sub vol}) and body weight (BW). One hundred patients referred for standard three-phase thoraco-abdominal MDCT examination were enrolled. BW was measured in the CT suite. Forty grams of iodine was administered intravenously (iodixanol 320 mg I/ml at 5 ml/s or iomeprol 400 mg I/ml at 4 ml/s) followed by a 50-ml saline flush. CTDI{sub vol} presented by the CT equipment during the parenchymal examination was recorded. The CM enhancement of the liver was defined as the attenuation HU of the liver parenchyma during the hepatic parenchymal phase minus the attenuation in the native phase. Liver parenchymal enhancement was negatively correlated to both CTDI{sub vol} (r = -0.60) and BW (r = -0.64), but the difference in correlation between those two was not significant. CTDI{sub vol} may replace BW when adjusting CM doses to body size. This makes it potentially feasible to automatically individualize CM dosage by CT. (orig.)

  8. Contrast Materials

    Science.gov (United States)

    ... is mixed with water before administration liquid paste tablet When iodine-based and barium-sulfate contrast materials ... for patients with kidney failure or allergies to MRI and/or computed tomography (CT) contrast material. Microbubble ...

  9. Low concentration contrast medium for dual-source computed tomography coronary angiography by a combination of iterative reconstruction and low-tube-voltage technique: Feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Minwen, E-mail: zhengmw2007@163.com; Liu, Ying, E-mail: yingyinglyly@126.com; Wei, Mengqi, E-mail: weimengqi2008@163.com; Wu, Yongjie, E-mail: wu18291988526@163.com; Zhao, Hongliang, E-mail: zhaohl1980@163.com; Li, Jian, E-mail: xjyylj@yeah.net

    2014-02-15

    Objectives: To assess the impact of low-concentration contrast medium on vascular enhancement, image quality and radiation dose of coronary CT angiography (cCTA) by using a combination of iterative reconstruction (IR) and low-tube-voltage technique. Materials and methods: One hundred patients were prospectively randomized to two types of contrast medium and underwent prospective electrocardiogram-triggering cCTA (Definition Flash, Siemens Healthcare; collimation: 128 mm × 0.6 mm; tube current: 300 mA s). Fifty patients received Iopromide 370 were scanned using the conventional tube setting (100 kVp or 120 kVp if BMI ≥ 25 kg/m{sup 2}) and reconstructed with filtered back projection (FBP). Fifty patients received Iodixanol 270 were scanned using the low-tube-voltage (80 kVp or 100 kVp if BMI ≥ 25 kg/m{sup 2}) technique and reconstructed with IR. CT attenuation was measured in coronary artery and other anatomical regions. Noise, image quality and radiation dose were compared. Results: Compared with two Iopromide 370 subgroups, Iomeprol 270 subgroups showed no significant difference in CT attenuation (576.63 ± 95.50 vs. 569.51 ± 118.93 for BMI < 25 kg/m{sup 2}, p = 0.647 and 394.19 ± 68.09 vs. 383.72 ± 63.11 for BMI ≥ 25 kg/m{sup 2}, p = 0.212), noise (in various anatomical regions of interest) and image quality (3.5 vs. 4.0, p = 0.13), but significantly (0.41 ± 0.17 vs. 0.94 ± 0.45 for BMI < 25 kg/m{sup 2}, p < 0.001 and 1.14 ± 0.24 vs. 2.37 ± 0.69 for BMI ≥ 25 kg/m{sup 2}, p < 0.001) lower radiation dose, which reflects dose saving of 56.4% and 51.9%, respectively. Conclusions: Combined IR with low-tube-voltage technique, a low-concentration contrast medium of 270 mg I/ml can still maintain the contrast enhancement without impairing image quality, as well as significantly lower the radiation dose.

  10. Impact of Impaired Renal Function on Gadolinium Retention After Administration of Gadolinium-Based Contrast Agents in a Mouse Model.

    Science.gov (United States)

    Kartamihardja, A Adhipatria P; Nakajima, Takahito; Kameo, Satomi; Koyama, Hiroshi; Tsushima, Yoshito

    2016-10-01

    The aim of this study was to investigate the impact of impaired renal function on gadolinium (Gd) retention in various organs after Gd-based contrast agent injection. After local animal care and review committee approval, 23 normal mice and 26 with renal failure were divided into 4 treatment groups (Gd-DTPA-BMA, 5 mmol/kg; Gd-DOTA, 5 mmol/kg; GdCl3, 0.02 mmol/kg; and saline, 250 μL). Each agent was intravenously administered on weekdays for 4 weeks. Samples were collected on days 3 (short-term) and 45 (long-term) after the last injection. Gadolinium concentrations were quantified by inductively coupled plasma-mass spectrometry. Three mice with renal failure and 2 normal mice in the GdCl3 group and 1 mouse with renal failure in the Gd-DTPA-BMA group died. In the Gd-DTPA-BMA group, impaired renal function increased short-term Gd retention in the liver, bone, spleen, skin, and kidney (P DTPA-BMA showed higher Gd retention than Gd-DOTA. Although Gd retention in the Gd-DOTA group was generally low, impaired renal function increased only long-term hepatic Gd retention. Hepatic and splenic Gd retentions were significantly higher than other organs' Gd retention in the GdCl3 group (P DTPA-BMA administration, long-term Gd retention for Gd-based contrast agents was almost unaffected by renal function, suggesting that the chemical structures of retained Gd may not be consistent and some Gd is slowly eliminated after initially being retained.

  11. Administration

    DEFF Research Database (Denmark)

    Bogen handler om den praksis, vi kalder administration. Vi er i den offentlige sektor i Danmark hos kontorfolkene med deres sagsmapper, computere, telefoner,, lovsamlinger,, retningslinier og regneark. I bogen udfoldes en mangfoldighed af konkrete historier om det administrative arbejde fra...... forskellige områder i den offentlige sektor. Hensigten er at forstå den praksis og faglighed der knytter sig til det administrative arbejde...

  12. Reducing the risk of iodine-based and MRI contrast media administration: Recommendation for a questionnaire at the time of booking

    DEFF Research Database (Denmark)

    Morcos, S.K.; Bellin, M.F.; Almen, T.

    2008-01-01

    This paper presents a practical questionnaire to be used when a contrast medium examination is requested. The questionnaire is based on the guidelines from the European Society of Urogenital Radiology. Its aim is to identify patients at increased risk of clinically relevant renal and non-renal ad......-renal adverse reactions to iodine-based and MRI contrast agents. The questionnaire should be completed by the referring physician when the examination is requested. (C) 2008 Elsevier Ireland Ltd. All rights reserved Udgivelsesdato: 2008/5......This paper presents a practical questionnaire to be used when a contrast medium examination is requested. The questionnaire is based on the guidelines from the European Society of Urogenital Radiology. Its aim is to identify patients at increased risk of clinically relevant renal and non...

  13. Prevalence of NSF following intravenous gadolinium-contrast media administration in dialysis patients with endstage renal disease

    Energy Technology Data Exchange (ETDEWEB)

    Heinz-Peer, Gertraud, E-mail: gertraud.heinz@meduniwien.ac.a [Department of Radiology, Medical University of Vienna (Austria); Neruda, Anita [Department of Radiology, Medical University of Vienna (Austria); Watschinger, Bruno; Vychytil, Andreas [Department of Nephrology, Medical University of Vienna (Austria); Geusau, Alexandra [Department of Dermatology, Medical University of Vienna (Austria); Haumer, Markus [Department of Internal Medicine II, Medical University of Vienna (Austria); Weber, Michael [Department of Radiology, Medical University of Vienna (Austria)

    2010-10-15

    Purpose: To evaluate the prevalence of nephrogenic systemic fibrosis (NSF) in a patient population being at highest risk for developing this disease and to evaluate possible risk factors. Materials and methods: The radiological records of 552 patients with ESRD being on hemodialysis (HD) or peritoneal dialysis (PD) were retrospectively reviewed to identify whether the patients underwent MR-examinations with or without intravenous administration of GBCA. In case of exposure to GBCA, the number of contrast injections, the benchmark and the cumulative doses of GBCA, and possible cofactors regarding pathogenesis of NSF were recorded. Diagnosis of NSF was confirmed either by deep skin biopsy or by review of medical and histopathological records. Data of NSF patients were compared with data of dialysis patients who did not develop NSF after MR-examinations. Results: 146 dialysis patients underwent MRI without i.v.-administration of GBCA. No case of NSF was observed in this patient population. 195/552 patients proved to have a total number of 325 well-documented exposures to GBCA. Seven different types of GBCA were used during these MR-examinations. NSF prevalence rate was 1.6%. One patient died of NSF. Three different types of GBCA were involved in 6 NSF cases. 4/6 proved to be confounded cases. The cumulative dose of GBCA, history of thrombosis, recent surgery, and the combination of HD and PD proved to be significant cofactors for the development of NSF (p < .05). No significant difference regarding residual renal clearance (p = .898) and residual urine volume (p = .083) was found between NSF and non-NSF patients. Conclusion: The prevalence of NSF proved to be much lower in this high risk patient group being exposed to GBCA compared to the literature. NSF was not observed in ESRD patients undergoing MRI without administration of GBCA. Our data support a positive association between cumulative dose of GBCA and development of NSF. No positive association was found

  14. Use of spiral CT and the contrast medium iohexol to determine in one session aortorenal morphology and the relative glomerular filtration rate of each kidney

    International Nuclear Information System (INIS)

    Frennby, B.; Almen, T.

    2001-01-01

    The aim of this study was to determine the relative glomerular filtration rate (GFR), i.e. the GFR of each kidney in percent of total GFR, by spiral CT. In 41 patients, who were part of a follow-up program after endoluminal stent grafting of aortic aneurysm, spiral CT with the contrast medium iohexol was used to evaluate the morphology of the aorta and kidneys. The opportunity was taken to utilize the already injected iohexol to determine the relative GFR with an extra CT sequence. In each patient two determinations were made, 6 or 12 months apart. The amount of a GFR marker accumulating in Bowman's space, tubuli, and renal pelvis within 2-3 min after i.v. injection, before any marker had left the kidney via the ureter, was defined as proportional to the GFR of that kidney. The renal accumulation of iohexol was obtained by spiral CT using 10-mm collimation and a table speed of 10 mm/s (pitch ratio 1:1) from the upper to the lower poles. The correlation coefficient between the relative GFR of each kidney determined at the first and second examination was excellent (r=0.99) with a median (range) difference of 1% (0-6%) of total GFR. The radiation dose calculated as the mean absorbed dose to the kidneys was 50 mGy and the effective dose 5 mSv. The morphology of aorta and kidneys and the relative GFR of each kidney can be determined in one session with spiral CT using iohexol as both angiographic contrast medium and as a GFR marker. It is also possible to take some plasma samples in the same session to determine iohexol concentration to calculate the body clearance of iohexol (or take plasma and urine samples to calculate the renal clearance of iohexol). (orig.)

  15. Optimizing dose and administration regimen of a high-relaxivity contrast agent for myocardial MRI late gadolinium enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Secchi, Francesco; Di Leo, Giovanni; Papini, Giacomo D.E. [Universita degli Studi di Milano, Dipartimento di Scienze Medico-Chirurgiche, Milan (Italy); IRCCS Policlinico San Donato, Radiology Unit, Via Morandi 30, 20097 San Donato Milanese, Milan (Italy); Giacomazzi, Francesca [IRCCS Policlinico San Donato, Unit of Cardiac Surgery, Via Morandi 30, 20097 San Donato Milanese, Milan (Italy); Di Donato, Marisa [University of Florence, Department of Critical Care Medicine, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese, Milan (Italy); Sardanelli, Francesco, E-mail: francesco.sardanelli@unimi.it [Universita degli Studi di Milano, Dipartimento di Scienze Medico-Chirurgiche, Milan (Italy); IRCCS Policlinico San Donato, Radiology Unit, Via Morandi 30, 20097 San Donato Milanese, Milan (Italy)

    2011-10-15

    Objectives: To investigate the time-course of late gadolinium enhancement of infarcted myocardium using gadobenate dimeglumine at different dosages and administration regimens. Materials and methods: After institutional review board approval and informed consent, we studied 13 patients (aged 63 {+-} 11 years) with chronic myocardial infarction. They underwent two gadobenate dimeglumine-enhanced MR examinations (interval 24-48 h) using short-axis inversion-recovery gradient-echo sequences, with the following two different protocols, in randomized order: 0.05 mmol/kg and imaging at the 2.5th, 5th, 7.5th and 10th minute plus 0.05 mmol/kg and imaging at the 12.5th, 15th, 17.5th and 20th minute; the same as before but using 0.1 mmol/kg for both contrast injections. Contrast-to-noise ratios (CNRs) between infarcted myocardium, non-infarcted myocardium and left ventricle cavity were calculated for each time-point (2.5-min steps). Friedman ANOVA was used for comparing the CNR time-course; Wilcoxon test for comparing CNR at the 10th and the 20th minute. Results: The CNR between infarcted and non-infarcted myocardium obtained at the 20th minute with 0.05 plus 0.05 mmol/kg resulted significantly higher than that obtained at the 10th minute with 0.05 mmol/kg (P = 0.033) while not significantly different from that obtained at the 10th (0.1 mm/kg) or at the 20th minute with 0.1 plus 0.1 mmol/kg. The CNR between infarcted myocardium and the left ventricle cavity obtained at the 20th minute with 0.05 plus 0.05 mmol/kg resulted significantly higher than all other measured values (P {<=} 0.017). Conclusion: Using gadobenate dimeglumine, 0.05 plus 0.05 mmol/kg allows for a higher CNR between infarcted myocardium and the left ventricle cavity allowing for reliable assessment of the sub-endocardial infarctions.

  16. The Preinterventional Cystatin-Creatinine-Ratio: A Prognostic Marker for Contrast Medium-Induced Acute Kidney Injury and Long-Term All-Cause Mortality.

    Science.gov (United States)

    Lüders, Florian; Meyborg, Matthias; Malyar, Nasser; Reinecke, Holger

    2015-01-01

    Contrast medium-induced acute kidney injury (CI-AKI) is an important iatrogenic complication following the injection of iodinated contrast media. The level of serum creatinine (SCr) is the currently accepted 'gold standard' to diagnose CI-AKI. Cystatin C (CyC) has been detected as a more sensitive marker for renal dysfunction. Both have their limitations. The role of the preinterventional CyC-SCr ratio for evaluating the risk for CI-AKI and long-term all-cause mortality was retrospectively analyzed in the prospective single-center 'Dialysis-versus-Diuresis trial'. CI-AKI was defined and staged according to the Acute Kidney Injury Network classification. Three hundred and seventy-three patients were included (average age 67.4 ± 10.2 years, 16.4% women, 29.2% with diabetes mellitus, mean baseline glomerular filtration rate 56.3 ± 20.2 ml/min/1.73 m(2) [as estimated by Chronic Kidney Disease Epidemiology Collaboration Serum Creatinine Cystatin C equation], 5.1% ejection fraction high significant association between preinterventional CyC-SCr ratio and long-term all-cause mortality (mean follow-up 649 days, hazards ratio 4.096, 95% CI 1.625-10.329, p = 0.003). The preinterventional CyC-SCr ratio is independently associated with CI-AKI and highly significant associated with long-term mortality after heart catheterization. © 2015 S. Karger AG, Basel.

  17. Determining the Sensitivity of CAT-ASVAB (Computerized Adaptive Testing- Armed Services Vocational Aptitude Battery) Scores to Changes in Item Response Curves with the Medium of Administration

    Science.gov (United States)

    1986-08-01

    most examinees. Therefore it appears psychometrically ac - ceptable for the CAT -ASVAB project to proceed without item recalibration based on...MEMORANDUM DETERMINING THE SENSITIVITY OF CAT -ASVAB SCORES TO CHANGES IN ITEM RESPONSE CURVES WITH THE MEDIUM OF ADMINISTRATION D. R. Divgi...Subj: Center for Naval Analyses Research Memorandum 86-189 End: (1) CNA Research Memorandum 86-189, "Determining the Sensitivity of CAT -ASVAB

  18. Monochromatic Spectral Computed Tomography with Low Iodine Concentration Contrast Medium in a Rabbit VX2 Liver Model:: Investigation of Image Quality and Detection Rate.

    Science.gov (United States)

    Zhou, Yue; Xu, Han; Hou, Ping; Dong, Jun Q; Wang, Ming Y; Gao, Jian B

    2016-04-01

    This study aimed to validate the feasibility of using virtual monochromatic spectral computed tomography (CT) with isotonic low iodine concentration contrast medium for VX2 hepatic tumors. Sixty New Zealand white rabbits with implanted VX2 hepatic tumors underwent two-phase contrast-enhanced spectral CT imaging on the 14th day after tumor implantation. They were randomly divided into groups A, B, and C, with 20 rabbits each (group A: 270 mg I/mL, monochromatic spectral images; group B: 370 mg I/mL, conventional 120 kVp images, 100% filtered back projection [FBP]; group C: 270 mg I/mL, conventional 120 kVp images, 100% FBP). Group A was further divided into two subgroups (subgroup A1: 100% FBP; subgroup A2: 50% FBP + 50% adaptive statistical iterative reconstruction). Objective evaluation (signal-to-noise ratio [SNR], contrast-to-noise ratio [CNR], and image noise), subjective rating score (image noise score, anatomical details score, overall image quality score, and lesion conspicuity score), CT dose index volume, and dose length product were compared between groups during two-phase contrast enhancement. The detection rates of the four groups were calculated as percentages. Image noise (SNR and CNR) among the four groups was statistically significant (P noise in group A2 was lower than in group A1, but higher than that in groups B and C (P noise score of group A2 was higher than that of the other three groups. In terms of the anatomic details score, the overall image quality score, and the lesion conspicuity score, the images of group A2 were superior to that of groups A1 and C. For hepatic tumor diameters more than or equal to 1.0 cm and less than 3.0 cm, group A achieved a higher detection rate than groups B and C. The CT dose index volume, dose length product, and effective dose in group A were significantly lower than that in groups B and C (P noise, increase detection rate for small tumors, and decrease radiation dose and iodine load in

  19. Intravenous administration of iodinated, non-ionic, low or isoosmolar contrast media: safety aspects; Intravenoese Anwendung von jodiertem, nichtionischem, nieder- bis isoosmolarem Kontrastmittel: Sicherheitsaspekte

    Energy Technology Data Exchange (ETDEWEB)

    Metz-Schimmerl, S.; Metz, V.; Schima, W.; Herold, C. [Universitaetsklinik fuer Radiodiagnostik und Ludwig Boltzmann-Institut fuer Klinische und Experimentelle Radiologie, Wien (Austria); Domanovits, H. [Universitaetsklinik fuer Notfallmedizin Wien, Wien (Austria)

    2002-01-01

    It iss the purpose of this review to provide information about the safe use of intravenously administered, iodinated, non-ionic, low or isoosmolar contrast media for radiological examinations, how to avoid adverse events, and how to react professionally in case of an anaphylactic reaction. Methods of prophylaxis and therapy for anaphylactic and chemotoxic effects of contrast media administration as well as absolute and relative contraindications are discussed. Medico-legal considerations of contrast agent administration, informed consent of patients, and methods of risk management for undesired contrast media reactions are considered in this article. Establishment of administration standards for contrast media is of tremendous importance to standardize radiological procedures. This basic radiological documentation is part of the institutional and individual legal safety management. (orig.) [German] Ziel dieses Artikels ist es, Kenntnisse zur sicheren Anwendung von intravenoes applizierten, jodierten, nichtionischen, nieder- bis isoosmolaren Roentgen-Kontrastmitteln zu vermitteln, um bei deren Verwendung unerwuenschte Wirkungen zu vermeiden oder im Falle eines anaphylaktischen Kontrastmittelzwischenfalls rasch und effektiv zu handeln. Neben Methoden der Verhuetung und Behandlung anaphylaktischer und chemotoxischer Wirkungen der Kontrastmittelgabe werden Einschraenkungen der Anwendung bei unterschiedlichen klinischen Bildern eroertert. Rechtliche Ueberlegungen zur Kontrastmittelanwendung, das Aufklaerungsgespraech und Praeventivmassnahmen zum Risiko-Management unerwuenschter Kontrastmittelwirkungen sind beruecksichtigt. Die Festlegung von Anwendungstandards fuer Kontrastmittel dient der Normierung medizinischen Vorgehens. Eine solche radiologische Basisdokumentation ist teil der institutionellen und individuellen rechtlichen Absicherung. (orig.)

  20. Sequential gadolinium-enhanced magnetic resonance angiography of the aortoiliac and the femoropopliteal arteries with repetitive administration of low-dose contrast agent

    International Nuclear Information System (INIS)

    Ito, Koichiro; Kumazaki, Tatsuo

    2000-01-01

    To obtain a wide-range contrast MR angiography in a single examination, we performed two sequential administrations of low-dose (0.08 mmol/kg) gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) with three dimensional inversion recovery prepared fast spoiled gradient recalled acquisition in the steady-state (3D IR-fast SPGR) sequence. Signal characteristics of the sequence were estimated by computed simulations and an in vitro study. A clinical study of 19 examinations was done with sequential MR angiography of the aortoiliac and femoropopliteal arteries. Great signal differences were observed between the high and low Gd concentrations. Higher Gd concentrations generated significantly stronger signals. Greater signals were produced at TIs of longer than 150 msec than at shorter than 100 msec. In the clinical study, the arteries were visualized with sufficient signals even with a small amount of contrast agent. Contrast-to-noise ratios between the arteries and surrounding skeletal muscles or fat tissues ranged from 10.5±9.6 to 4.7±2.2 and 6.6±2.8 to -3.1±11.2, respectively. No venous enhancement was found with diluted contrast agent on the second MR angiography. Two consecutive contrast MR angiographies can be obtained with repetitive administration of low-dose contrast agent. (author)

  1. Sequential gadolinium-enhanced magnetic resonance angiography of the aortoiliac and the femoropopliteal arteries with repetitive administration of low-dose contrast agent

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Koichiro [Nippon Medical School, Inba, Chiba (Japan). Chiba Hokusoh Hospital; Kumazaki, Tatsuo

    2000-12-01

    To obtain a wide-range contrast MR angiography in a single examination, we performed two sequential administrations of low-dose (0.08 mmol/kg) gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) with three dimensional inversion recovery prepared fast spoiled gradient recalled acquisition in the steady-state (3D IR-fast SPGR) sequence. Signal characteristics of the sequence were estimated by computed simulations and an in vitro study. A clinical study of 19 examinations was done with sequential MR angiography of the aortoiliac and femoropopliteal arteries. Great signal differences were observed between the high and low Gd concentrations. Higher Gd concentrations generated significantly stronger signals. Greater signals were produced at TIs of longer than 150 msec than at shorter than 100 msec. In the clinical study, the arteries were visualized with sufficient signals even with a small amount of contrast agent. Contrast-to-noise ratios between the arteries and surrounding skeletal muscles or fat tissues ranged from 10.5{+-}9.6 to 4.7{+-}2.2 and 6.6{+-}2.8 to -3.1{+-}11.2, respectively. No venous enhancement was found with diluted contrast agent on the second MR angiography. Two consecutive contrast MR angiographies can be obtained with repetitive administration of low-dose contrast agent. (author)

  2. Cerebral bone subtraction CT angiography using 80 kVp and sinogram-affirmed iterative reconstruction: contrast medium and radiation dose reduction with improvement of image quality

    Energy Technology Data Exchange (ETDEWEB)

    Nagayama, Yasunori [Kumamoto City Hospital, Department of Radiology, Kumamoto (Japan); Kumamoto University, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Nakaura, Takeshi; Oda, Seitaro; Kidoh, Masafumi; Utsunomiya, Daisuke; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Tsuji, Akinori; Urata, Joji; Furusawa, Mitsuhiro; Yuki, Hideaki; Hirarta, Kenichiro [Kumamoto City Hospital, Department of Radiology, Kumamoto (Japan)

    2017-02-15

    The purpose of this study was to evaluate the feasibility of a contrast medium (CM), radiation dose reduction protocol for cerebral bone-subtraction CT angiography (BSCTA) using 80-kVp and sinogram-affirmed iterative reconstruction (SAFIRE). Seventy-five patients who had undergone BSCTA under the 120- (n = 37) or the 80-kVp protocol (n = 38) were included. CM was 370 mgI/kg for the 120-kVp and 296 mgI/kg for the 80-kVp protocol; the 120- and the 80-kVp images were reconstructed with filtered back-projection (FBP) and SAFIRE, respectively. We compared effective dose (ED), CT attenuation, image noise, and contrast-to-noise ratio (CNR) of two protocols. We also scored arterial contrast, sharpness, depiction of small arteries, visibility near skull base/clip, and overall image quality on a four-point scale. ED was 62% lower at 80- than 120-kVp (0.59 ± 0.06 vs 1.56 ± 0.13 mSv, p < 0.01). CT attenuation of the internal carotid artery (ICA) and middle cerebral artery (MCA) was significantly higher on 80- than 120-kVp (ICA: 557.4 ± 105.7 vs 370.0 ± 59.3 Hounsfield units (HU), p < 0.01; MCA: 551.9 ± 107.9 vs 364.6 ± 62.2 HU, p < 0.01). The CNR was also significantly higher on 80- than 120-kVp (ICA: 46.2 ± 10.2 vs 36.9 ± 7.6, p < 0.01; MCA: 45.7 ± 10.0 vs 35.7 ± 9.0, p < 0.01). Visibility near skull base and clip was not significantly different (p = 0.45). The other subjective scores were higher with the 80- than the 120-kVp protocol (p < 0.05). The 80-kVp acquisition with SAFIRE yields better image quality for BSCTA and substantial reduction in the radiation and CM dose compared to the 120-kVp with FBP protocol. (orig.)

  3. The administration and the environmental behavior of the small and medium industrial companies: The case of a city of Argentina

    International Nuclear Information System (INIS)

    Guzman Ramos, Aldo; Fernandez, Guillermina

    2001-01-01

    The present article approaches the subject of the management and the environmental behavior in the industrial activity, especially in the small and medium companies, a city of Argentina. It is considers that the environmentalist strategies can be a possible exit to the socioeconomic and environmental crisis, but single for the great companies; since the rest of the companies presents/displays serious difficulties (economic, social, psychological, etc.) in order to initiate a sustainable industrial development

  4. Clinical application of intravascular administration of non-ionic, low osmolar contrast agent, Ioversol (Optiray 320) and its side effects comparison with Meglumine Iothalamate (Conray 60)

    International Nuclear Information System (INIS)

    Hong, Hyun Sook; Kim, Dae Ho; Lee, Hae Kyung; Chung, Moo Chan; Choi, Deuk Lin; Kwon, Kuy Hyang; Kim, Ki Jung

    1990-01-01

    Ioversol, the non-ionic, low osmolar contrast agent has been well characterized chemically and in terms of basic toxicity testing. Ioversol has a fomula similar to that of other nonionic agent. We review the results of intravascular use of this contrast agent, compared ionic contrast media(Meglumine Iothalamate (Conray 60)). Each study was assessed for imaging quality,and patients were monitored vital signs, changes of hematology and blood chemistry and urinalysis before and after contrast administration and were observed for occurrence of side effects. A small number of side effects were reported but no clinically significant sequelae in Ioversol group and much less vital sign changes compared with Conray group. There were no significant changes in vital signs related to the use of Ioversol, and no significant alterations in the renal function parameter or other blood chemistry and hematology measurement were encountered in both contrast media. In most cases, the image qualities were good. In conclusion, Ioversol is safe, well tolerated and efficious for use in intravascular contrast agent, and less vital sign changes and side effect than ionic Meglumine Iothalamte, and Ioversol is likely to provide a useful and acceptable alternative to other low osmolar and nonionic contrast agents

  5. Distribution of medium-chain FA in different lipid classes after administration of specific structured TAG in rats

    DEFF Research Database (Denmark)

    Mu, Huiling; Høy, Carl-Erik

    2002-01-01

    Structured TAG (STAG) containing medium-chain FA (MCFA) in the sn-1,3 positions and essential FA in the sn-2 position were synthesized by lipase-catalyzed acidolysis. In our previous studies we found that part of the MCFA from STAG could be absorbed in the small intestine; however, it was unclear...... how they were absorbed. In order to get a better understanding of the metabolism of STAG to improve future design and application of STAG, in the present study lymph lipids collected after feeding STAG were fractionated into different classes and the FA composition of each lipid class was studied...

  6. Choice of intravenous contrast material for CT

    International Nuclear Information System (INIS)

    Cohen, M.D.; Herman, E.; Herron, D.; White, S.T.; Smith, J.A.; Cory, D.A.

    1989-01-01

    For CT, minor side effects (e.g., nausea, vomiting, pain) following intravenous administration of contrast medium may degrade image quality by causing patient motion or by delaying scanning. The objective of this study was to see if nonionic contrast agents offer advantages in reducing the incidence of such side effects. One hundred five pediatric patients randomly received iohexol (Omnipaque), Iopamidol (Isovue), or diatrizoate sodium (Hypaque). Contrast medium was given in doses of 2 mL/kg body weight (300 mg of iodine per milliliter). The results are presented in the paper

  7. Changes in risk of immediate adverse reactions to iodinated contrast media by repeated administrations in patients with hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Naoto Fujiwara

    Full Text Available BACKGROUND: To elucidate whether repeated exposures to iodinated contrast media increase the risk of adverse reaction. MATERIALS AND METHODS: We retrospectively reviewed 1,861 patients with hepatocellular carcinoma who visited authors' institution, a tertiary referral center, between 2004 and 2008. We analyzed cumulative probability of adverse reactions and risk factors. We categorized all symptoms into hypersensitivity reactions, physiologic reactions, and other reactions, according to the American College of Radiology guidelines, and evaluated each category as an event. We estimated the association between hazard for adverse reactions and the number of cumulative exposures to contrast media. We also evaluated subsequent contrast media injections and adverse reactions. RESULTS: There were 23,684 contrast media injections in 1,729 patients. One hundred and thirty-two patients were excluded because they were given no contrast media during the study period. Adverse reactions occurred in 196 (0.83% patients. The cumulative incidence at 10(th, 20(th, and 30(th examination was 7.9%, 15.2%, and 24.1%, respectively. Presence of renal impairment was found to be one of risk factors for adverse reactions. The estimated hazard of overall adverse reaction gradually decreased until around 10(th exposure and rose with subsequent exposures. The estimated hazard of hypersensitivity showed V-shaped change with cumulative number of exposures. The estimated hazard of physiologic reaction had a tendency toward decreasing and that of other reaction had a tendency toward increasing. Second adverse reaction was more severe than the initial in only one among 130 patients receiving subsequent injections. CONCLUSION: Repeated exposures to iodinated contrast media increase the risk of adverse reaction.

  8. Changes in risk of immediate adverse reactions to iodinated contrast media by repeated administrations in patients with hepatocellular carcinoma.

    Science.gov (United States)

    Fujiwara, Naoto; Tateishi, Ryosuke; Akahane, Masaaki; Taguri, Masataka; Minami, Tatsuya; Mikami, Shintaro; Sato, Masaya; Uchino, Koji; Uchino, Kouji; Enooku, Kenichiro; Kondo, Yuji; Asaoka, Yoshinari; Yamashiki, Noriyo; Goto, Tadashi; Shiina, Shuichiro; Yoshida, Haruhiko; Ohtomo, Kuni; Koike, Kazuhiko

    2013-01-01

    To elucidate whether repeated exposures to iodinated contrast media increase the risk of adverse reaction. We retrospectively reviewed 1,861 patients with hepatocellular carcinoma who visited authors' institution, a tertiary referral center, between 2004 and 2008. We analyzed cumulative probability of adverse reactions and risk factors. We categorized all symptoms into hypersensitivity reactions, physiologic reactions, and other reactions, according to the American College of Radiology guidelines, and evaluated each category as an event. We estimated the association between hazard for adverse reactions and the number of cumulative exposures to contrast media. We also evaluated subsequent contrast media injections and adverse reactions. There were 23,684 contrast media injections in 1,729 patients. One hundred and thirty-two patients were excluded because they were given no contrast media during the study period. Adverse reactions occurred in 196 (0.83%) patients. The cumulative incidence at 10(th), 20(th), and 30(th) examination was 7.9%, 15.2%, and 24.1%, respectively. Presence of renal impairment was found to be one of risk factors for adverse reactions. The estimated hazard of overall adverse reaction gradually decreased until around 10(th) exposure and rose with subsequent exposures. The estimated hazard of hypersensitivity showed V-shaped change with cumulative number of exposures. The estimated hazard of physiologic reaction had a tendency toward decreasing and that of other reaction had a tendency toward increasing. Second adverse reaction was more severe than the initial in only one among 130 patients receiving subsequent injections. Repeated exposures to iodinated contrast media increase the risk of adverse reaction.

  9. Delayed allergy-like reactions to X-ray contrast media administration focusing on clinical aspects. First expert meeting

    International Nuclear Information System (INIS)

    Sviridov, N.K.

    1998-01-01

    Materials presented at the first expert meeting of leading specialists in medical radiology are briefly described. The include 14 reports of the scientists of Germany, England, Japan, USA, Finland, Austria. The reports concert delayed allergy-like response to X-ray contrast media accepting on clinical aspects and analysis of nonionic dimeric isotonic media application

  10. Body surface area adapted iopromide 300 mg/ml versus 370 mg/ml contrast medium injection protocol: Influence on quantitative and clinical assessment in combined PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Verburg, Frederik A., E-mail: fverburg@ukaachen.de [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany); Maastricht University Medical Center, Department of Nuclear Medicine, P. Debyelaan 25, 6229 HX Maastricht (Netherlands); Apitzsch, Jonas [RWTH Aachen University Hospital, Department of Diagnostic and Interventional Radiology, Pauwelsstraße 30, 52074 Aachen (Germany); Lensing, Carina [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany); Kuhl, Christiane K. [RWTH Aachen University Hospital, Department of Diagnostic and Interventional Radiology, Pauwelsstraße 30, 52074 Aachen (Germany); Pietsch, Hubertus [Bayer Pharma AG, Müllerstrasse 178, 13353 Berlin (Germany); Mottaghy, Felix M. [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany); Maastricht University Medical Center, Department of Nuclear Medicine, P. Debyelaan 25, 6229 HX Maastricht (Netherlands); Behrendt, Florian F. [RWTH Aachen University Hospital, Department of Nuclear Medicine, Pauwelsstraße 30, 52074 Aachen (Germany)

    2013-12-01

    Purpose: To investigate the quantitative and qualitative differences between combined positron emission tomography and computed X-ray tomography (PET/CT) enhanced with contrast medium with either an iodine concentration 300 mg/ml or 370 mg/ml. Materials and methods: 120 consecutive patients scheduled for F-18-Fluorodeoxyglucose (FDG) PET/CT were included. The first (second) 60 patients received contrast medium with 300 (370) mg iodine/ml. Intravenous injection protocols were adapted for an identical iodine delivery rate (1.3 mg/s) and body surface area (BSA) adapted iodine dose (22.26 g I/m{sup 2}). Maximum and mean standardized uptake values (SUV{sub max}; SUV{sub mean}) and contrast enhancement (HU) were determined in the ascending aorta, the abdominal aorta, the inferior vena cava, the portal vein, the liver and the right kidney in the venous contrast medium phase. PET data were evaluated visually for the presence of malignancy and image quality. Results: Both media caused significantly higher values for HU, SUV{sub mean} and SUV{sub max} for the enhanced PET/CT than the non-enhanced one (all p < 0.01). There were no significant differences in the degree of increase of HU, SUV{sub mean} and SUV{sub max} between the two contrast media at any anatomic site (all p > 0.05). Visual evaluation of lesions showed no differences between contrast and non-contrast PET/CT or between the two different contrast media (p = 0.77). Conclusion: When using a constant iodine delivery rate and total iodine dose in a BSA adapted injection protocol, there are no quantitative or qualitative differences in either CT or PET between contrast media with an iodine concentration of 300 mg/ml and 370 mg/ml, respectively.

  11. Perforations during contrast enema

    International Nuclear Information System (INIS)

    Vogel, H.; Steinkamp, U.; Grabbe, E.; Allgemeines Krankenhaus Ochsenzoll, Hamburg

    1983-01-01

    During contrast enema, perforation into the retroperitoneal space can be differentiated from perforation into the peritoneum and perforation into the intestinal wall associated with formation of barium granulomas or submucosal spreading of the contrast medium. Other special forms are perforation with contrast medium embolism of diverticula; of the processus vermiformis; penetration of contrast medium into fistulous systems and from the operated areas. Risk factors are: balloon catheter, intestinal tubes with a hard tip, preternatural anus, excessive enema pressure, contrast medium additions, preceding manipulations, intestinal diseases, advanced age and delegation of manipulations to assistants and unskilled staff. Children are particularly at risk. (orig.) [de

  12. Contrast induced nephropathy

    DEFF Research Database (Denmark)

    Stacul, Fulvio; van der Molen, Aart J; Reimer, Peter

    2011-01-01

    PURPOSE: The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 1999 guidelines on contrast medium-induced nephropathy (CIN). AREAS COVERED: Topics reviewed include the definition of CIN, the choice of contrast medium, the prophylactic me....../min/1.73 m (2) is CIN risk threshold for intravenous contrast medium. • Hydration with either saline or sodium bicarbonate reduces CIN incidence. • Patients with eGFR = 60 ml/min/1.73 m (2) receiving contrast medium can continue metformin normally....

  13. Gadolinium retention after administration of contrast agents based on linear chelators and the recommendations of the European Medicines Agency

    International Nuclear Information System (INIS)

    Dekkers, Ilona A.; Roos, Rick; Molen, Aart J. van der

    2018-01-01

    The Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) earlier this year recommended to suspend some marketing authorisations for Gadolinium Containing Contrast Agents (GCCAs) based on linear chelators due to the potential risk of gadolinium retention in the human body. These recommendations have recently been re-evaluated by EMA's Committee for Medicinal Products for Human Use (CHMP), and confirmed the final opinion of the European Medicines Agency. This editorial provides an overview of the available GCCAs and summarises the recent evidence of gadolinium retention. Moreover, a critical appraisal of the strengths and limitations of the scientific evidence currently available on gadolinium retention is given. (orig.)

  14. Contrast induced nephropathy

    DEFF Research Database (Denmark)

    Stacul, Fulvio; van der Molen, Aart J; Reimer, Peter

    2011-01-01

    PURPOSE: The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 1999 guidelines on contrast medium-induced nephropathy (CIN). AREAS COVERED: Topics reviewed include the definition of CIN, the choice of contrast medium, the prophylactic me...

  15. Evaluation of renal quantitative T2* changes on MRI following administration of ferumoxytol as a T2* contrast agent.

    Science.gov (United States)

    Hedgire, Sandeep S; McDermott, Shaunagh; Wojtkiewicz, Gregory R; Abtahi, Seyed Mahdi; Harisinghani, Mukesh; Gaglia, Jason L

    2014-01-01

    To evaluate the time-dependent changes in regional quantitative T2* maps of the kidney following intravenous administration of ferumoxytol. Twenty-four individuals with normal kidney function underwent T2*-weighted MRI of the kidney before, immediately after, and 48 hours after intravenous administration of ferumoxytol at a dose of 4 mg/kg (group A, n=12) or 6 mg/kg (group B, n=12). T2* values were statistically analyzed using two-tailed paired t-tests. In group A, the percentage changes from baseline to immediate post and baseline to 48 hours were 85.3% and 64.2% for the cortex and 90.8% and 64.6% for the medulla, respectively. In group B, the percentage changes from baseline to immediate post and baseline to 48 hours were 85.2% and 73.4% for the cortex and 94.5% and 74% for the medulla, respectively. This difference was significant for both groups (P<0.0001). There is significant and differential uptake of ferumoxytol in the cortex and medulla of physiologically normal kidneys. This differential uptake may offer the ability to interrogate renal cortex and medulla with possible clinical applications in medical renal disease and transplant organ assessment. We propose an organ of interest based dose titration of ferumoxytol to better differentiate circulating from intracellular ferumoxytol particles.

  16. Informed consent for the administration of an intravenous contrast agent: importance and determinants of patient refusal; Consentimiento informado para la administracion de contraste intravenoso. Importancia y factores determinantes del rechazo por los pacientes

    Energy Technology Data Exchange (ETDEWEB)

    Martel, J. [Fundacion Hospital Alcorcon. Madrid (Spain); Garcia-Diaz, J. D. [Hospital Universitario Principe de Asturias. Alcala de Henares. Madrid (Spain)

    1999-07-01

    We proposed to determine the proportion of patients who refuse to undergo intravenous contrast administration and the factors that influence their refusal. Our series consisted of 442 patients who were supposed to undergo imaging studies involving the intravenous injection of an iodine contrast. In a personal interview, the patients were issued a questionnaire specifically designed for this study. The following parameters were recorded: sex, age, inpatient or outpatient status, medical history available, person who informed them about the procedure, person signing the informed consent (patient or other) , highest academic degree, attitude toward receiving the information and degree of concern after reading and signing the consent form. In our series 8.6% of the patients (95% confidence interval: 6-11.2) refused to sign the informed consent form. In addition, there were a number of patients who delayed the procedure or hindered the daily work schedule by some other means. When the relationship between each of the variables studied and refusal to sign the consent form was assessed, significant associations were observed between the latter and the academic level of the patient, his or her degree of concern and having received the information from a trained person. There was also a nearly significant trend toward the association between refusal and the patient's background. Relatively few patients refuse to sign the informed consent to receive intravenous contrast administration but this negative decision interferes with the health care practice. It is possible to identify certain correctable factors that influence the patient in this respect. (Author) 13 refs.

  17. Evaluation of bowel distension and bowel wall visualization according to patient positions during administration of oral contrast media for CT enterography.

    Science.gov (United States)

    Lee, Seul Bi; Kim, Seung Ho; Son, Jung Hee; Baik, Ji Yeon

    2017-12-01

    To compare small bowel distension and bowel wall visualization among three different patients' positions (supine, sitting and right decubitus) during administration of oral contrast media in preparation for CT enterography (CTE). A total of 150 consecutive patients (104 males and 46 females; mean age 34.6 years, range 15-78 years) who were scheduled to undergo CTE were recruited. Patients were randomly allocated into the three position groups during oral contrast media administration, and there were 50 patients in each group. Two blinded radiologists independently scored the luminal distension and visualization of the bowel wall using a continuous 5-point scale (1: worst and 5: best) at the jejunum and ileum. The Mann-Whitney U test was used to evaluate differences between any two groups among the three positions for bowel distension and wall visualization. For ileal distension, the supine and sitting positions performed better than the right decubitus position [for reader 1, mean: 3.4/3.2/2.9 (hereafter, supine/sitting/right decubitus in order), p = 0.002/0.033; for reader 2, 3.3/3.0/2.6, p 0.05, respectively). For bowel wall visualization, the supine and sitting positions were superior to the right decubitus position for the ileum when scored by one reader (4.0/3.8/3.4, p = 0.001/0.015). Supine and sitting positions during the administration of oral contrast media provided better ileal distension than the right decubitus position in obtaining CTE. Advances in knowledge: The performance of CTE largely depends on adequate luminal distension and wall visualization. As the terminal ileum is the predominant site of small bowel pathology for inflammatory bowel disease, the supine or sitting position would be preferable for patients who are suspected of having small bowel pathology.

  18. [Treatment with metformin in type 2 diabetes mellitus - new routines when renal function is reduced and in connection with administration of iodine contrast media].

    Science.gov (United States)

    Sterner, Gunnar; Frid, Anders

    2018-04-03

    Metformin is eliminated through glomerular filtration and tubular secretion in the kidneys. New guidelines recommend use of metformin down to a GFR of 30 mL/min under the condition that the dose is adjusted. As the risk of inducing lactic acidosis is very low in connection with administration of iodine contrast media, new recommendations in Sweden say that metformin must be stopped only when GFR is below 45 mL/min. Determination of metformin levels in serum is useful to guide therapeutic dose when GFR is low but also to confirm that lactic acidosis is caused by metformin.

  19. Control of asthma for reducing the risk of bronchospasm in asthmatics undergoing general anesthesia and/or intravascular administration of radiographic contrast media.

    Science.gov (United States)

    Liccardi, Gennaro; Salzillo, Antonello; De Blasio, Francesco; D'Amato, Gennaro

    2009-07-01

    It is well known that patients suffering from bronchial asthma undergoing surgical procedures requiring general anesthesia (GA) or the administration of water soluble radiographic contrast media (RCM) have an increased risk of potentially severe bronchospasm. Nevertheless, little attention has been devoted to the possible preventive measures to reduce the occurrence of this potentially life-threatening event. It has been shown that the most important risk factor for bronchospasm during GA induction and/or the use of RCM is represented by a high degree of bronchial hyperreactivity with airway instability not adequately controlled by long-term anti-inflammatory treatment. The aim of this commentary is to underline the need for an accurate clinical and functional evaluation of asthmatics undergoing surgical procedures requiring GA or radiological procedures requiring the administration of RCM, as well as to suggest a stepwise preventive pharmacological approach for reducing the risk of bronchospasm. The authors' suggestions represent clinical experience of the respiratory section of an internal hospital-based working group whose aim is the prevention of asthmatic/anaphylactic/anaphylactoid reactions during the administration of anesthetics and/or RCM. The MEDLINE database was searched with a combination of keywords: general anesthesia, radio contrast media [and] bronchial asthma. The main limitation of this commentary is the scarcity of available literature on this topic. The authors suggest a therapeutic approach before surgical procedures requiring GA and/or RCM administration based on the degree of asthma control as assessed by clinical/functional criteria. In this setting, in addition to the necessity of obtaining the best control of airway reactivity, the authors suggest that an optimal control of asthma symptoms in 'real life' conditions might likely constitute a safety issue in asthmatic patients in the case of emergency procedures.

  20. Contrasting effects of systemic and central sibutramine administration on the intake of a palatable diet in the rat.

    Science.gov (United States)

    Pratt, Wayne E; Connolly, Megan E

    2010-10-22

    Sibutramine hydrochloride monohydrate is the only centrally active weight-modifying agent currently approved by the FDA for long-term use in the treatment of obesity. Systemic sibutramine treatment has been shown to reduce food intake in humans and rodent models in a manner that is consistent with the enhancement of satiety mechanisms. Although it is generally assumed that the hypophagic effects of the drug are mediated by actions within the brain, the locus or loci of these effects remains unclear. These experiments compared the effects of systemic and intracranial injections of sibutramine on the intake of a palatable diet in non-deprived animals. Consistent with prior reports, systemic injections of sibutramine hydrochloride (at 0, 0.5, 1.0, or 3.0mg/kg sibutramine i.p.) dose-dependently reduced feeding on a high fat/high sucrose diet across a 2-h feeding session, but did not alter water intake or locomotor activity. In contrast, bilateral injections of sibutramine (at 0.0, 2.0, 4.0 and 10.0μg/0.5μl/side) into either the paraventricular nucleus of the hypothalamus (PVN) or the medial nucleus accumbens shell (ACb) significantly and dose-dependently increased food intake of the sweetened fat diet. ACb treatment also modestly inhibited locomotor behavior; intracranial injections had no effect on water consumption. These experiments are the first to suggest that sibutramine treatment may have distinct actions upon separate neural circuits that modulate food intake behavior in the rat. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  1. Comparison of MR imaging after administration of dysprosium-based magnetic-susceptibility contrast media with diffusion-weighted MR imaging in evaluation of regional cerebral ischemia

    International Nuclear Information System (INIS)

    Moseley, M.E.; Kucharczyk, J.; Kurhanewicz, J.; Mintorovitch, J.; Cohen, Y.; Rocklage, S.; Quay, S.C.; Norman, D.

    1989-01-01

    This paper reports on a study to establish whether a nonionic T2-shortening contrast agent, Dy-DTPA-bis(methylamide) (Dy-DTPA-BMA), would facilitate early detection of stroke-induced cerebral perfusion deficits. The sensitivity of susceptibility-enhanced MR imaging was compared with that of diffusion-weighted MR imaging in the same cats subjected to unilateral occlusion of the middle cerebral artery (MCA). A 2-T unit, equipped with self-shielded gradient coils (± 20 G/cm, 15-cm bore size), was used in conjunction with an 8.5-cm inner diameter low-pass bird cage proton imaging coil. Diffusion-weighted images displayed increased signal intensity in the ischemic MCA territory less than 1 hour after occlusion, whereas T2-weighted MR images without contrast enhancement usually failed to depict injury for 2--3 hours after toke. With contrast administration (0.5 mmoles/kg of Dy-DTPA-BMA), however, T2-weighted images revealed perfusion deficits (hyperintensity) within 1 hour after MCA occlusion, and these corresponded to the anatomic regions of ischemic injury shown on diffusion-weighted MR images

  2. Diffusion weighted imaging of liver lesions suspect for metastases: Apparent diffusion coefficient (ADC) values and lesion contrast are independent from Gd-EOB-DTPA administration

    International Nuclear Information System (INIS)

    Benndorf, Matthias; Schelhorn, Juliane; Dietzel, Matthias; Kaiser, Werner A.; Baltzer, Pascal A.T.

    2012-01-01

    Purpose: Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced liver MRI is widely used for detection and differentiation of focal liver lesions. Diffusion weighted imaging (DWI) including apparent diffusion coefficient (ADC) measurements is increasingly utilised as a fast and, with limitations, quantitative method for liver lesion detection and characterisation. Herein we investigate whether the administration of Gd-EOB-DTPA affects DWI. Materials and methods: 31 consecutive patients referred to standardised liver MRI (1.5 T, Gd-EOB-DTPA, 0.025 mmol/kg) were retrospectively reviewed. All underwent a breathhold DWI sequence before and after contrast agent administration (EPI-DWI, TR/TE (effective): 2100/62 ms, b-values: 0 and 800 s/mm 2 ). Patients with previously treated liver lesions were excluded. Signal intensity of lesion, parenchyma and noise on DWI images as well as the ADC value were measured after identification by two observers in consensus using manually placed regions of interest. The reference standard was imaging follow-up determined separately by two radiologists. Data analysis included signal-to-noise (SNR) ratio and contrast-to-noise ratio (CNR) calculations, comparisons were drawn by employing multiple Bonferroni corrected Wilcoxon signed-rank tests. Results: 50 malignant and 39 benign lesions were identified. Neither SNR, CNR nor ADC values showed significant differences between pre- and postcontrast DWI. Both pre- and postcontrast ADC values differed significantly between benign and malignant lesions (P < 0.001). Conclusion: We did not identify a significant influence of Gd-EOB-DTPA on DWI of liver lesions. This allows for individual tailoring of imaging protocols according to clinical needs.

  3. Effect of the Administration of Alpha-Lipoic Acid on Contrast Sensitivity in Patients with Type 1 and Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Anna Gębka

    2014-01-01

    Full Text Available The aim of this study was to estimate the effects of oral supplementation of alpha-lipoic acid (ALA on contrast sensitivity (CS in patients with type 1 diabetes mellitus (T1DM and type 2 diabetes mellitus (T2DM. The study included 12 patients with T1DM aged 43±12 years, 48 patients with T2DM aged 59±10 years, and 20 control subjects aged 33±8 years. Patients from each studied group, including the control group, were randomly assigned to receive 300 mg of ALA orally once daily for 3 months. CS was evaluated with the Functional Acuity Contrast Test (FACT, Stereo Optical. In the group of patients with T1DM receiving ALA for 3 months CS remained stable and improved in those with T2DM. Reduction of CS in both T1DM and T2DM patients without alpha-lipoic acid supplementation was observed. In the control group on alpha-lipoic acid supplementation, CS improvement was noticed at one spatial frequency. Changes in the CS were observed, despite stable visual acuity and eye fundus image in all studied subjects. Our study demonstrated that oral administration of alpha-lipoic acid had influence on CS in both T1DM and T2DM patients.

  4. Effect of duration of contrast material injection on peak enhancement times and values of the aorta, main portal vein, and liver at dynamic MDCT with the dose of contrast medium tailored to patient weight

    International Nuclear Information System (INIS)

    Erturk, S.M.; Ichikawa, T.; Sou, H.; Tsukamoto, T.; Motosugi, U.; Araki, T.

    2008-01-01

    Aim: To investigate the effects of contrast material injection duration on peak enhancement times and attenuation values of the aorta, main portal vein, and liver at MDCT when the dose of contrast material is adjusted to patient weight. Material and methods: Seventy-five patients were randomly assigned to one of five groups, with durations of injection of 25, 30, 35, 40, or 45 s. All patients were injected with 2 ml/kg iodine (300 mg/ml). Attenuation values and peak enhancement times for the aorta, main portal vein, and liver were determined. The relationship between patient weight and enhancement times and values, the differences regarding peak enhancement times, and the relationship between injection duration and enhancement values were investigated using Pearson correlation, analysis of variance (ANOVA), and Spearman rank correlation, respectively. Results: No significant correlations were seen between patient weight and peak enhancement times or values. Mean peak enhancement times for the aorta, main portal vein, and liver were 9-11 s, 18-22 s, and 30-34 s, respectively (p > 0.05). The correlations between injection duration and peak enhancement values were significant and negative. Conclusions: Regardless of patient weight and injection duration, peak enhancement times of aorta, main portal vein and liver were approximately 10, 20, and 30 s, respectively. The enhancement values tended to be higher for shorter injection durations

  5. Dominance hierarchies, diversity and species richness of vascular plants in an alpine meadow: contrasting short and medium term responses to simulated global change

    Directory of Open Access Journals (Sweden)

    Juha M. Alatalo

    2014-05-01

    Full Text Available We studied the impact of simulated global change on a high alpine meadow plant community. Specifically, we examined whether short-term (5 years responses are good predictors for medium-term (7 years changes in the system by applying a factorial warming and nutrient manipulation to 20 plots in Latnjajaure, subarctic Sweden. Seven years of experimental warming and nutrient enhancement caused dramatic shifts in dominance hierarchies in response to the nutrient and the combined warming and nutrient enhancement treatments. Dominance hierarchies in the meadow moved from a community being dominated by cushion plants, deciduous, and evergreen shrubs to a community being dominated by grasses, sedges, and forbs. Short-term responses were shown to be inconsistent in their ability to predict medium-term responses for most functional groups, however, grasses showed a consistent and very substantial increase in response to nutrient addition over the seven years. The non-linear responses over time point out the importance of longer-term studies with repeated measurements to be able to better predict future changes. Forecasted changes to temperature and nutrient availability have implications for trophic interactions, and may ultimately influence the access to and palatability of the forage for grazers. Depending on what anthropogenic change will be most pronounced in the future (increase in nutrient deposits, warming, or a combination of them both, different shifts in community dominance hierarchies may occur. Generally, this study supports the productivity–diversity relationship found across arctic habitats, with community diversity peaking in mid-productivity systems and degrading as nutrient availability increases further. This is likely due the increasing competition in plant–plant interactions and the shifting dominance structure with grasses taking over the experimental plots, suggesting that global change could have high costs to biodiversity in the

  6. Efficient optical Kerr gate of Bi2O3–B2O3–SiO2 glass for acquiring high contrast ballistic imaging in turbid medium

    International Nuclear Information System (INIS)

    Zhan, Pingping; Tan, Wenjiang; Wu, Bin; Si, Jinhai; Chen, Feng; Hou, Xun; Liu, Xin

    2013-01-01

    We investigated the ballistic imaging of a 1.41 line pair mm −1 section of a resolution test chart hidden behind a solution of polystyrene spheres with a femtosecond optical Kerr gate (OKG). A better transillumination image contrast could be acquired with an OKG of Bi 2 O 3 –B 2 O 3 –SiO 2 (BI) glass than that with an OKG of fused silica in a highly scattering media, which indicated that the BI glass was a better OKG medium due to its large nonlinear refractive index. (paper)

  7. Histology and Gadolinium Distribution in the Rodent Brain After the Administration of Cumulative High Doses of Linear and Macrocyclic Gadolinium-Based Contrast Agents

    Science.gov (United States)

    Lohrke, Jessica; Frisk, Anna-Lena; Frenzel, Thomas; Schöckel, Laura; Rosenbruch, Martin; Jost, Gregor; Lenhard, Diana Constanze; Sieber, Martin A.; Nischwitz, Volker; Küppers, Astrid; Pietsch, Hubertus

    2017-01-01

    Objectives Retrospective studies in patients with primary brain tumors or other central nervous system pathologies as well as postmortem studies have suggested that gadolinium (Gd) deposition occurs in the dentate nucleus (DN) and globus pallidus (GP) after multiple administrations of primarily linear Gd-based contrast agents (GBCAs). However, this deposition has not been associated with any adverse effects or histopathological alterations. The aim of this preclinical study was to systematically examine differences between linear and macrocyclic GBCAs in their potential to induce changes in brain and skin histology including Gd distribution in high spatial resolution. Materials and Methods Fifty male Wistar-Han rats were randomly allocated into control (saline, n = 10 rats) and 4 GBCA groups (linear GBCAs: gadodiamide and gadopentetate dimeglumine, macrocyclic GBCAs: gadobutrol and gadoteridol; n = 10 rats per group). The animals received 20 daily intravenous injections at a dose of 2.5 mmol Gd/kg body weight. Eight weeks after the last GBCA administration, the animals were killed, and the brain and skin samples were histopathologically assessed (hematoxylin and eosin; cresyl violet [Nissl]) and by immunohistochemistry. The Gd concentration in the skin, bone, brain, and skeletal muscle samples were analyzed using inductively coupled plasma mass spectroscopy (ICP-MS, n = 4). The spatial Gd distribution in the brain and skin samples was analyzed in cryosections using laser ablation coupled with ICP-MS (LA-ICP-MS, n = 3). For the ultra-high resolution of Gd distribution, brain sections of rats injected with gadodiamide or saline (n = 1) were assessed by scanning electron microscopy coupled to energy dispersive x-ray spectroscopy and transmission electron microscopy, respectively. Results No histological changes were observed in the brain. In contrast, 4 of 10 animals in the gadodiamide group but none of the animals in other groups showed macroscopic and histological

  8. Histology and Gadolinium Distribution in the Rodent Brain After the Administration of Cumulative High Doses of Linear and Macrocyclic Gadolinium-Based Contrast Agents.

    Science.gov (United States)

    Lohrke, Jessica; Frisk, Anna-Lena; Frenzel, Thomas; Schöckel, Laura; Rosenbruch, Martin; Jost, Gregor; Lenhard, Diana Constanze; Sieber, Martin A; Nischwitz, Volker; Küppers, Astrid; Pietsch, Hubertus

    2017-06-01

    Retrospective studies in patients with primary brain tumors or other central nervous system pathologies as well as postmortem studies have suggested that gadolinium (Gd) deposition occurs in the dentate nucleus (DN) and globus pallidus (GP) after multiple administrations of primarily linear Gd-based contrast agents (GBCAs). However, this deposition has not been associated with any adverse effects or histopathological alterations. The aim of this preclinical study was to systematically examine differences between linear and macrocyclic GBCAs in their potential to induce changes in brain and skin histology including Gd distribution in high spatial resolution. Fifty male Wistar-Han rats were randomly allocated into control (saline, n = 10 rats) and 4 GBCA groups (linear GBCAs: gadodiamide and gadopentetate dimeglumine, macrocyclic GBCAs: gadobutrol and gadoteridol; n = 10 rats per group). The animals received 20 daily intravenous injections at a dose of 2.5 mmol Gd/kg body weight. Eight weeks after the last GBCA administration, the animals were killed, and the brain and skin samples were histopathologically assessed (hematoxylin and eosin; cresyl violet [Nissl]) and by immunohistochemistry. The Gd concentration in the skin, bone, brain, and skeletal muscle samples were analyzed using inductively coupled plasma mass spectroscopy (ICP-MS, n = 4). The spatial Gd distribution in the brain and skin samples was analyzed in cryosections using laser ablation coupled with ICP-MS (LA-ICP-MS, n = 3). For the ultra-high resolution of Gd distribution, brain sections of rats injected with gadodiamide or saline (n = 1) were assessed by scanning electron microscopy coupled to energy dispersive x-ray spectroscopy and transmission electron microscopy, respectively. No histological changes were observed in the brain. In contrast, 4 of 10 animals in the gadodiamide group but none of the animals in other groups showed macroscopic and histological nephrogenic systemic fibrosis-like skin

  9. Iodine-based contrast media, multiple myeloma and monoclonal gammopathies: literature review and ESUR Contrast Media Safety Committee guidelines.

    Science.gov (United States)

    Stacul, Fulvio; Bertolotto, Michele; Thomsen, Henrik S; Pozzato, Gabriele; Ugolini, Donatella; Bellin, Marie-France; Bongartz, Georg; Clement, Olivier; Heinz-Peer, Gertraud; van der Molen, Aart; Reimer, Peter; Webb, Judith A W

    2018-02-01

    Many radiologists and clinicians still consider multiple myeloma (MM) and monoclonal gammopathies (MG) a contraindication for using iodine-based contrast media. The ESUR Contrast Media Safety Committee performed a systematic review of the incidence of post-contrast acute kidney injury (PC-AKI) in these patients. A systematic search in Medline and Scopus databases was performed for renal function deterioration studies in patients with MM or MG following administration of iodine-based contrast media. Data collection and analysis were performed according to the PRISMA statement 2009. Eligibility criteria and methods of analysis were specified in advance. Cohort and case-control studies reporting changes in renal function were included. Thirteen studies were selected that reported 824 iodine-based contrast medium administrations in 642 patients with MM or MG, in which 12 unconfounded cases of PC-AKI were found (1.6 %). The majority of patients had intravenous urography with high osmolality ionic contrast media after preparatory dehydration and purgation. MM and MG alone are not risk factors for PC-AKI. However, the risk of PC-AKI may become significant in dehydrated patients with impaired renal function. Hypercalcaemia may increase the risk of kidney damage, and should be corrected before contrast medium administration. Assessment for Bence-Jones proteinuria is not necessary. • Monoclonal gammopathies including multiple myeloma are a large spectrum of disorders. • In monoclonal gammopathy with normal renal function, PC-AKI risk is not increased. • Renal function is often reduced in myeloma, increasing the risk of PC-AKI. • Correction of hypercalcaemia is necessary in myeloma before iodine-based contrast medium administration. • Bence-Jones proteinuria assessment in myeloma is unnecessary before iodine-based contrast medium administration.

  10. Influence of tri-iodinated water soluble X-ray contrast medium for uro, angio and cholangiography on the plasmic coagulation system

    International Nuclear Information System (INIS)

    Kaps, H.P.

    1982-01-01

    In-vitro coagulation studies comprising overall and individual factor determinations were carried out with the aim of clarifying the nature of unforeseen incidents arising from the use of contrast media in X-ray diagnosis. In all tests a reproducible, dose-dependent, exponential coagulation inhibition was obtained, and resulted in complete inhibition at higher dose levels. This effect occurred by a factor of ten earlier, on average, with iodine ipamide, representative of liver passage bile CM, compared to uro, and angiographic CM diatrozoate and iodine thalamate used for kidney passage. Hepatotrophic CM act initially hypercoagulative at low dises through activation of the thrombin coagulase complex; later inhibition of coagulation sets in through direct fixation on functional proteins and their subsequent denaturation. A discussion is given of the importance of direct physico-chemical toxicity, histamine liberation reactions and cellular reactions, and the controversial role of the complement system is presented. (orig./MG) [de

  11. Indirect MR venography: contrast medium protocols, postprocessing and combination in diagnosing pulmonary emboli with MRI; Indirekte MR-Phlebografie: Kontrastmittelprotokolle, Nachverarbeitung und Kombination mit Lungenemboliediagnostik in der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Kluge, A.; Bachmann, G. [Diagnostische Radiologie, Kerckhoff-Klinik, Bad Nauheim (Germany); Rominger, M. [Diagnostische Radiologie, Phillips-Univ. Marburg (Germany); Schoenburg, M. [Herzchirurgie, Kerckhoff-Klinik, Bad Nauheim (Germany)

    2004-07-01

    Purpose: Integration of MR venography in a comprehensive MR imaging protocol in patients with suspected pulmonary embolism (PE) and evaluation of contrast media dosage, timing and postprocessing for diagnostic accuracy. Materials and Methods: Fortyeight consecutive inpatients with suspected PE or deep vein thrombosis were examined by MR venography according to one of the following protocols: protocol I: MR venography only, 0.25 mmol/kg bodyweight (BW) Gadopentate dimeglumine(Gd-DTPA) as single dose, bolus timing; protocol II: MR angiography of pulmonary arteries with a cumulative dosage of 0.25 mmol/kg contrast media, modification of coil setting for MR venography without further contrast media application; protocol III: as protocol II but with 0.125 mmol/kg BW, followed by MR venography. Signal-to-noise ratio, contrast-to-noise ratio, number of definable vascular segments and image quality were evaluated. The results were compared to conventional bilateral venography. Results: All MR venography examinations were of diagnostic quality and the examination time was below 10 min. MR venography could be performed in all 48 patients comparted to 43 of 48 patients for conventional venography. Significantly more superficial and deep veins of the leg could be visualized by MR venography (94% compared to 83% for conventional venography). Sensitivity and specificity were 100% and 92%, respectively. Quality differed significantly between 0.125 mmol/kg (protocol III) and 0.25 mmol/kg Gd-DTPA (protocols I and II) while timing did not influence quality (protocol I vs. II). (orig.) [German] Ziel: Integration der MR-Phlebografie in ein umfassendes Konzept der MRT-Diagnostik bei Verdacht auf Lungenembolie (LE). Untersuchung des Einflusses von Kontrastmittelmenge, -bolusform und Verzoegerungszeit sowie der Nachverarbeitung auf die diagnostische Qualitaet von MR-Phlebografien. Material und Methode: Bei 48 konsekutiven stationaeren Patienten mit Verdacht auf Beinvenenthrombose (TVT

  12. Preoperative mapping of arterial spinal supply using 3.0-T MR angiography with an intravasal contrast medium and high-spatial-resolution steady-state

    International Nuclear Information System (INIS)

    Mordasini, Pasquale; El-Koussy, Marwan; Schmidli, Jürg; Bonel, Harald Marcel; Ith, Michael; Gralla, Jan; Schroth, Gerhard; Hoppe, Hanno

    2012-01-01

    Introduction: Preoperative mapping of the arterial spinal supply prior to thoracoabdominal aortic aneurysm repair is highly relevant because of high risk for postoperative ischemic spinal cord injuries such as paraparesis or paraplegia. Methods: Twenty-four consecutive patients prior to surgical thoracoabdominal aortic aneurysm repair were investigated. All patients underwent steady-state MR angiography (MRA) of the spinal vasculature with 3-T MRI. The sequence used was a steady-state coronary 3D FLASH with 0.7-mm isotropic voxels. MRA was performed using an intravasal contrast agent. Studies were evaluated by three readers including delineation of arterial spinal supply including both aortic origin and spinal canal entry by three readers. Results: Identification and localization of the Adamkiewicz artery and its spinal canal entry was successful in all patients. Overall depiction of the vascular anatomy was graded as very good in 3 (12.5%), good in 14 (58.4%), sufficient in 5 (20.8%), and poor in 2 (8.3%) patients. Depiction of segmental artery aortic exit level was graded as good in 6 (25.0%), sufficient in 10 (41.7%), poor in 4 (16.7%) and not identifiable in 4 (16.7%) patients. Delineation of segmental artery entry level into the spinal canal was graded as very good in 4 (16.7%), good in 11 (45.8%), sufficient in 6 (25.0%), and poor in 3 (12.5%) patients. Conclusions: The use of 3-T MRA with an intravascular contrast agent and steady-state enables AKA localization including its segmental arteries with regard to the level of aortic origin and spinal canal entry in most patients.

  13. Automated tube voltage selection for radiation dose and contrast medium reduction at coronary CT angiography using 3{sup rd} generation dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Schoepf, U.J. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Poole, Zachary B.; Varga-Szemes, Akos; De Cecco, Carlo N. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Canstein, Christian [Siemens Medical Solutions, Malvern, PA (United States); Caruso, Damiano [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Radiological Sciences, Oncology and Pathology, Rome (Italy); Bamberg, Fabian; Nikolaou, Konstantin [Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany)

    2016-10-15

    To investigate the relationship between automated tube voltage selection (ATVS) and body mass index (BMI) and its effect on image quality and radiation dose of coronary CT angiography (CCTA). We evaluated 272 patients who underwent CCTA with 3{sup rd} generation dual-source CT (DSCT). Prospectively ECG-triggered spiral acquisition was performed with automated tube current selection and advanced iterative reconstruction. Tube voltages were selected by ATVS (70-120 kV). BMI, effective dose (ED), and vascular attenuation in the coronary arteries were recorded. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Five-point scales were used for subjective image quality analysis. Image quality was rated good to excellent in 98.9 % of examinations without significant differences for proximal and distal attenuation (all p ≥.0516), whereas image noise was rated significantly higher at 70 kV compared to ≥100 kV (all p <.0266). However, no significant differences were observed in SNR or CNR at 70-120 kV (all p ≥.0829). Mean ED at 70-120 kV was 1.5 ± 1.2 mSv, 2.4 ± 1.5 mSv, 3.6 ± 2.7 mSv, 5.9 ± 4.0 mSv, 7.9 ± 4.2 mSv, and 10.7 ± 4.1 mSv, respectively (all p ≤.0414). Correlation analysis showed a moderate association between tube voltage and BMI (r =.639). ATVS allows individual tube voltage adaptation for CCTA performed with 3{sup rd} generation DSCT, resulting in significantly decreased radiation exposure while maintaining image quality. (orig.)

  14. Feasibility of low-dose contrast medium high pitch CT angiography for the combined evaluation of coronary, head and neck arteries.

    Directory of Open Access Journals (Sweden)

    Zhiwei Wang

    Full Text Available PURPOSE: To evaluate the image quality and radiation dose of combined heart, head, and neck CT angiography (CTA using prospectively electrocardiography (ECG-triggered high-pitch spiral scan protocol, compared with single coronary CTA. MATERIALS AND METHODS: 151 consecutive patients were prospectively included and randomly divided into three groups. Group 1 (n = 47 underwent combined heart, neck, and head CTA using prospectively ECG-triggered high-pitch spiral (Flash scan protocol with a single-phase intravenous injection of iodinated contrast and saline flush; Group 2 (n = 51 underwent single coronary CTA with Flash scan protocol; and Group 3 (n = 53 underwent single coronary CTA with prospective sequence scan protocol. All patients were examined on a dual source CT (Definition FLASH. The image quality was determined for each CT study. RESULTS: Patients of scanning protocol Group 1, 2, and 3 showed no significant differences in age, sex, heart rates, and BMI. Evaluation of coronary artery image quality showed comparable results in the three scanning protocol groups on a per patient-based analysis. In group 1, image quality was found to be sufficient to be diagnostic in all arterial segments of carotid arteries. The mean dose-length product (DLP for group 1 was 256.3±24.5 mGy×cm and was significantly higher in comparison with group 2 (93.4±19.9 mGy×cm; p < 0.001. However, there was no significant difference of DLP between group 1 and group 3 (254.1±69.9 mGy×cm. CONCLUSIONS: The combined heart, neck, and head arteries scan using prospectively electrocardiography (ECG-triggered high-pitch spiral scan protocol in 1 single examination resulted in an excellent opacification of the aorta, the carotid arteries, and the coronary arteries and provided a good image quality with low radiation dose.

  15. Dialysis and contrast media

    International Nuclear Information System (INIS)

    Morcos, Sameh K.; Thomsen, Henrik S.; Webb, Judith A.W.

    2002-01-01

    In a previous survey we revealed uncertainty among responders about (a) whether or not to perform hemodialysis in patients with severely reduced renal function who had received contrast medium; and (b) when to perform hemodialysis in patients on regular treatment with hemodialysis or continuous ambulatory dialysis who received contrast medium. Therefore, the Contrast Media Safety Committee of The European Society of Urogenital Radiology decided to review the literature and to issue guidelines. The committee performed a Medline search. Based on this, a report and guidelines were prepared. The report was discussed at the Ninth European Symposium on Urogenital Radiology in Genoa, Italy. Hemodialysis and peritoneal dialysis safely remove both iodinated and gadolinium-based contrast media. The effectiveness of hemodialysis depends on many factors including blood and dialysate flow rate, permeability of dialysis membrane, duration of hemodialysis and molecular size, protein binding, hydrophilicity, and electrical charge of the contrast medium. Generally, several hemodialysis sessions are needed to removal all contrast medium, whereas it takes 3 weeks for continuous ambulatory dialysis to remove the agent completely. There is no need to schedule the dialysis in relation to the injection of iodinated or MR contrast media or the injection of contrast agent in relation to the dialysis program. Hemodialysis does not protect poorly functioning kidneys against contrast-medium-induced nephrotoxicity. Simple guidelines are given. (orig.)

  16. Preliminary study of the scan-delay-time during the combined examation of CT perfusion and CT angiography after contrast media administration in cerebral and cervical CT angiography

    International Nuclear Information System (INIS)

    Cai Wu; Gong Jianping; Zhu Jiangtao; Qiao Fang; Chen Guangqiang; Zhang Bo; Yi Bixing; Qian Minghui

    2010-01-01

    Objective: To discuss the feasibility of the time to peak of cerebral CT perfusion (CTP) in predicting the scan-delay-time after contrast media administration in cerebral and cervical CT angiography (CTA). Methods: Retrospective Analysis was performed in eighty patients who had been examined with cerebral and cervical CTA, they were divided randomly into two groups. Group A:40 patients were performed by the method of experience of 20 seconds as scan-delay-time. Group B:the other 40 patients were examined with the combination scanning technology of CTP-CTA. They were all measured with enhancement value of CT in the M1 segment of left middle cerebral artery, superior sagittal sinus , left common carotid artery adjacent to the fourth cervical vertebrace and internal jugular vein, and then calculate the difference between the arterys and the veins in the same layer. Statistical significance was determined with t test. Results: (1)The enhancement value of CT in the cerebral and cervical artery vessels and the resolving power between the arterys and the veins in the same layer of group B were higher than that in group A. (2) Group B whose cerebral and cervical artery vessels rescontructed from the raw CT data set showed clearly; There were an advance in 3 cases (7.5%), a delay in 5 cases (12.5%) in group A whose cerebral and cervical artery vessels rescontructed from the raw CT data set didn't show clearly.Conclusion It's a satisfactory method based on successful cerebral and cervical CTA study to take the time to peak in CT perfusion as the scan-delay-time during the combined examination of CTP and CTA with 64-detector spiral CT. (authors)

  17. Quantification and Assessment of the Chemical Form of Residual Gadolinium in the Brain After Repeated Administration of Gadolinium-Based Contrast Agents

    Science.gov (United States)

    Frenzel, Thomas; Apte, Chirag; Jost, Gregor; Schöckel, Laura; Lohrke, Jessica; Pietsch, Hubertus

    2017-01-01

    Objective Multiple clinical and preclinical studies have reported a signal intensity increase and the presence of gadolinium (Gd) in the brain after repeated administration of Gd-based contrast agents (GBCAs). This bioanalytical study in rat brain tissue was initiated to investigate whether the residual Gd is present as intact GBCA or in other chemical forms by using tissue fractionation and chromatography. Materials and Methods Rats were divided randomly in 6 groups of 10 animals each. They received 10 daily injections of 2.5 mmol/kg bodyweight of 1 of 5 different GBCAs: linear GBCAs such as gadodiamide (Omniscan; GE Healthcare), gadopentetate dimeglumine (Gd-DTPA, Magnevist; Bayer), or gadobenate dimeglumine (Multihance; Bracco) and macrocyclic GBCAs such as gadobutrol (Gadovist; Bayer) and gadoterate meglumine (Gd-DOTA, Dotarem; Guerbet) or saline. On days 3 and 24 after the last injection (p.i.), 5 randomly chosen animals of each group were killed by exsanguination, and their brains were excised and divided into cerebrum, pons, and cerebellum. The brain sections were homogenized by sonication in ice-cold buffer at pH 7.4. Soluble and insoluble fractions were separated by centrifugation, and the soluble fractions were further separated by gel permeation chromatography (GPC). The Gd concentration in all tissue fractions and in the GPC eluate was measured by inductively coupled plasma–mass spectrometry. In a recovery control experiment, all GBCAs were spiked to blank brain tissue and more than 94% recovery of Gd in the tissue fractions was demonstrated. Results Only traces of the administered Gd were found in the rat brain tissue on day 3 and day 24 p.i. In the animals treated with macrocyclic GBCAs, Gd was found only in the soluble brain fraction and was present solely as low molecular weight molecules, most likely the intact GBCA. In the animals treated with linear GBCAs Gd was found to a large extent in the insoluble tissue fraction. The Gd concentration in

  18. Quantification and Assessment of the Chemical Form of Residual Gadolinium in the Brain After Repeated Administration of Gadolinium-Based Contrast Agents: Comparative Study in Rats.

    Science.gov (United States)

    Frenzel, Thomas; Apte, Chirag; Jost, Gregor; Schöckel, Laura; Lohrke, Jessica; Pietsch, Hubertus

    2017-07-01

    Multiple clinical and preclinical studies have reported a signal intensity increase and the presence of gadolinium (Gd) in the brain after repeated administration of Gd-based contrast agents (GBCAs). This bioanalytical study in rat brain tissue was initiated to investigate whether the residual Gd is present as intact GBCA or in other chemical forms by using tissue fractionation and chromatography. Rats were divided randomly in 6 groups of 10 animals each. They received 10 daily injections of 2.5 mmol/kg bodyweight of 1 of 5 different GBCAs: linear GBCAs such as gadodiamide (Omniscan; GE Healthcare), gadopentetate dimeglumine (Gd-DTPA, Magnevist; Bayer), or gadobenate dimeglumine (Multihance; Bracco) and macrocyclic GBCAs such as gadobutrol (Gadovist; Bayer) and gadoterate meglumine (Gd-DOTA, Dotarem; Guerbet) or saline. On days 3 and 24 after the last injection (p.i.), 5 randomly chosen animals of each group were killed by exsanguination, and their brains were excised and divided into cerebrum, pons, and cerebellum. The brain sections were homogenized by sonication in ice-cold buffer at pH 7.4. Soluble and insoluble fractions were separated by centrifugation, and the soluble fractions were further separated by gel permeation chromatography (GPC). The Gd concentration in all tissue fractions and in the GPC eluate was measured by inductively coupled plasma-mass spectrometry. In a recovery control experiment, all GBCAs were spiked to blank brain tissue and more than 94% recovery of Gd in the tissue fractions was demonstrated. Only traces of the administered Gd were found in the rat brain tissue on day 3 and day 24 p.i. In the animals treated with macrocyclic GBCAs, Gd was found only in the soluble brain fraction and was present solely as low molecular weight molecules, most likely the intact GBCA. In the animals treated with linear GBCAs Gd was found to a large extent in the insoluble tissue fraction. The Gd concentration in the soluble fraction was comparable to the

  19. A method for the investigation of cholegraphic contrast media

    International Nuclear Information System (INIS)

    Otto, H.

    1982-01-01

    Isolated perfused rat livers were used for investigating possible interactions between two simultaneously injected contrast media, and which technique, using parenteral application of cholegraphic media, is optimal. The results show that excretion of a parenteral contrast medium is reduced by giving an oral contrast medium at the same time. Simultaneous administration of two different contrast media therefore does not result in improved diagnostic information. The effect depends on the dose, and a sufficiently long interval should be observed between giving an oral and a parenteral contrast medium. A comparison of excretion values following injection of a bolus and prolonged infusion shows higher biliary contrast concentration and increased excretion after a single injection. Comparing only the period after the infusion, no difference was found between these two methods of administration. The single injection offers pharmacokinetic advantages, but an infusion is better tolerated and has fewer side effects. A rapid infusion of 10 to 15 minutes is therefore recommended as the optimal means of administration. (orig.) [de

  20. Value of 100 kVp scan with sinogram-affirmed iterative reconstruction algorithm on a single-source CT system during whole-body CT for radiation and contrast medium dose reduction: an intra-individual feasibility study.

    Science.gov (United States)

    Nagayama, Y; Nakaura, T; Oda, S; Tsuji, A; Urata, J; Furusawa, M; Tanoue, S; Utsunomiya, D; Yamashita, Y

    2018-02-01

    To perform an intra-individual investigation of the usefulness of a contrast medium (CM) and radiation dose-reduction protocol using single-source computed tomography (CT) combined with 100 kVp and sinogram-affirmed iterative reconstruction (SAFIRE) for whole-body CT (WBCT; chest-abdomen-pelvis CT) in oncology patients. Forty-three oncology patients who had undergone WBCT under both 120 and 100 kVp protocols at different time points (mean interscan intervals: 98 days) were included retrospectively. The CM doses for the 120 and 100 kVp protocols were 600 and 480 mg iodine/kg, respectively; 120 kVp images were reconstructed with filtered back-projection (FBP), whereas 100 kVp images were reconstructed with FBP (100 kVp-F) and the SAFIRE (100 kVp-S). The size-specific dose estimate (SSDE), iodine load and image quality of each protocol were compared. The SSDE and iodine load of 100 kVp protocol were 34% and 21%, respectively, lower than of 120 kVp protocol (SSDE: 10.6±1.1 versus 16.1±1.8 mGy; iodine load: 24.8±4versus 31.5±5.5 g iodine, p<0.01). Contrast enhancement, objective image noise, contrast-to-noise-ratio, and visual score of 100 kVp-S were similar to or better than of 120 kVp protocol. Compared with the 120 kVp protocol, the combined use of 100 kVp and SAFIRE in WBCT for oncology assessment with an SSCT facilitated substantial reduction in the CM and radiation dose while maintaining image quality. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  1. Augmented Quadruple-Phase Contrast Media Administration and Triphasic Scan Protocol Increases Image Quality at Reduced Radiation Dose During Computed Tomography Urography.

    Science.gov (United States)

    Saade, Charbel; Mohamad, May; Kerek, Racha; Hamieh, Nadine; Alsheikh Deeb, Ibrahim; El-Achkar, Bassam; Tamim, Hani; Abdul Razzak, Farah; Haddad, Maurice; Abi-Ghanem, Alain S; El-Merhi, Fadi

    The aim of this article was to investigate the opacification of the renal vasculature and the urogenital system during computed tomography urography by using a quadruple-phase contrast media in a triphasic scan protocol. A total of 200 patients with possible urinary tract abnormalities were equally divided between 2 protocols. Protocol A used the conventional single bolus and quadruple-phase scan protocol (pre, arterial, venous, and delayed), retrospectively. Protocol B included a quadruple-phase contrast media injection with a triphasic scan protocol (pre, arterial and combined venous, and delayed), prospectively. Each protocol used 100 mL contrast and saline at a flow rate of 4.5 mL. Attenuation profiles and contrast-to-noise ratio of the renal arteries, veins, and urogenital tract were measured. Effective radiation dose calculation, data analysis by independent sample t test, receiver operating characteristic, and visual grading characteristic analyses were performed. In arterial circulation, only the inferior interlobular arteries in both protocols showed a statistical significance (P contrast-to-noise ratio than protocol A (protocol B: 22.68 ± 13.72; protocol A: 14.75 ± 5.76; P contrast media and triphasic scan protocol usage increases the image quality at a reduced radiation dose.

  2. Computer-based image analysis in radiological diagnostics and image-guided therapy: 3D-Reconstruction, contrast medium dynamics, surface analysis, radiation therapy and multi-modal image fusion

    International Nuclear Information System (INIS)

    Beier, J.

    2001-01-01

    This book deals with substantial subjects of postprocessing and analysis of radiological image data, a particular emphasis was put on pulmonary themes. For a multitude of purposes the developed methods and procedures can directly be transferred to other non-pulmonary applications. The work presented here is structured in 14 chapters, each describing a selected complex of research. The chapter order reflects the sequence of the processing steps starting from artefact reduction, segmentation, visualization, analysis, therapy planning and image fusion up to multimedia archiving. In particular, this includes virtual endoscopy with three different scene viewers (Chap. 6), visualizations of the lung disease bronchiectasis (Chap. 7), surface structure analysis of pulmonary tumors (Chap. 8), quantification of contrast medium dynamics from temporal 2D and 3D image sequences (Chap. 9) as well as multimodality image fusion of arbitrary tomographical data using several visualization techniques (Chap. 12). Thus, the software systems presented cover the majority of image processing applications necessary in radiology and were entirely developed, implemented and validated in the clinical routine of a university medical school. (orig.) [de

  3. Evaluation of the hemodynamic effects of intravenous administration of ionic and nonionic contrast materials: implications for deriving physiologic measurements from computed tomography and digital cardiovascular imaging

    International Nuclear Information System (INIS)

    Higgins, C.B.; Berber, K.H.; Mattrey, R.F.; Slutsky, R.A.

    1982-01-01

    The effects of intravenous injection of an ionic contrast material (Renografin-76 [meglumine sodium diatrizoate]) on left ventricular pressure, internal diameter, and wall thickness, and on coronary and femoral hemodynamics were compared with those of a hydrolytically stable nonionic contrast material (iohexol). Renografin-76 caused drastic biphasic changes in left ventricular pressure and dp/dt (rate of change of left ventricular pressure), and moderate changes in end systolic dimension. Iohexol caused little or no change in left ventricular pressure and dimensions. In addition, Renografin-76 caused marked arterial hypotension and large increases in coronary and femoral blood lows, while iohexol caused no significant change in arterial pressure and coronary blood flow, and a mild increase in femoral blood flow. Based on these findings, it is concluded that iohexol is preferable to standard ionic contrast material for deriving basal physiologic information from computed tomographic and digital vascular studies

  4. Experimental investigations on the influence of the contrast medium Iopamiro 300 mixed with vegetal mucus on the nasolacrimal system and external eye tissues; Badania doswiadczalne nad wplywem srodka cieniujacego Iopamiro 300 ze sluzem roslinnym na drogi lzowe i przedni odcinek oka

    Energy Technology Data Exchange (ETDEWEB)

    Rubaj, B.; Koper, S. [Akademia Rolnicza, Lublin (Poland); Wolski, T.; Toczowski, J.; Wolski, J.; Langwinska-Wosko, E. [Akademia Medyczna, Lublin (Poland)

    1994-12-31

    Using low osmolality, nonionized contrast medium Iopamiro-300, Bracco mixed with the mucus prepared from the seed flax (``Linum usitatissimum, L.``), a dacryocistorhinography was performed experimentally on 8 healthy mongrel dogs. Assessing the occurrence of local and general complications was the aim of the investigation. On the basis of a radiographic examination it has been shown that the mixture of the contrast medium and seed flax mucus appeared to be a very useful compound for dacryocistorhinography, especially for the evaluation of nasolacrimal duct system course and its patency. Clinical observations and a histological examination proved that this compound of the contrast medium was well tolerated by the mucous membrane of the nasolacrimal system and the external eye tissues. (author). 21 refs, 4 figs.

  5. Contrast-induced encephalopathy following cardiac catheterization.

    Science.gov (United States)

    Spina, Roberto; Simon, Neil; Markus, Romesh; Muller, David Wm; Kathir, Krishna

    2017-08-01

    To describe the epidemiology, pathophysiology, clinical presentation, and management of contrast-induced encephalopathy (CIE) following cardiac catheterization. CIE is an acute, reversible neurological disturbance directly attributable to the intra-arterial administration of iodinated contrast medium. The PubMed database was searched and all cases in the literature were retrieved and reviewed. 52 reports of CIE following cardiac catheterization were found. Encephalopathy, motor and sensory disturbances, vision disturbance, opthalmoplegia, aphasia, and seizures have been reported. Transient cortical blindness is the most commonly reported neurological syndrome, occurring in approximately 50% of cases. The putative mechanism involves disruption of the blood brain barrier and direct neuronal injury. Contrast-induced transient vasoconstriction has also been implicated. Symptoms typically appear within minutes to hours of contrast administration and resolve entirely within 24-48 hr. Risk factors may include hypertension, diabetes mellitus, renal impairment, the administration of large volumes of iodinated contrast, percutaneous coronary intervention or selective angiography of internal mammary grafts, and previous adverse reaction to iodinated contrast. Characteristic findings on cerebral imaging include cortical and sub-cortical contrast enhancement on computed tomography (CT). Imaging findings in CIE may mimic subarachnoid hemorrhage or cerebral ischemia; the Hounsfield scale on CT and the apparent diffusion coefficient on magnetic resonance imaging (MRI) are useful imaging tools in distinguishing these entities. In some cases, brain imaging is normal. Prognosis is excellent with supportive management alone. CIE tends to recur, although re-challenge with iodinated contrast without adverse effects has been documented. CIE is an important clinical entity to consider in the differential diagnosis of stroke following cardiac catheterization. Given that prognosis is

  6. A randomized controlled trial comparing hydration therapy to additional hemodialysis or N-acetylcysteine for the prevention of contrast medium-induced nephropathy: the Dialysis-versus-Diuresis (DVD) Trial.

    Science.gov (United States)

    Reinecke, H; Fobker, M; Wellmann, J; Becke, B; Fleiter, J; Heitmeyer, C; Breithardt, G; Hense, H-W; Schaefer, R M

    2007-03-01

    Contrast medium-induced nephropathy (CIN) is a serious complication with increasing frequency and an unfavorable prognosis. Previous analyses of surrogate parameters have suggested beneficial effects of hemodialysis that are assessed in this randomized clinical trial. We performed a prospective single-center trial in 424 consecutive patients with serum creatinine concentrations between 1.3- 3.5 mg/dl who underwent elective coronary angiography. Patients were randomized to one of three treatment strategies with all patients receiving pre- and postprocedural hydration: One group received no additional therapy, patients in the second group were hemodialyzed once, and the third group received oral N-acetylcysteine. The frequency of CIN (defined as an increase in serum creatinine>or=0.5 mg/dl) from 48 to 72 h after catheterization was 6.1% in the hydration-only group, 15.9% with hemodialysis treatment, and 5.3% in the N-ACC group (intention-to-treat analysis; P=0.008). There were no differences between the treatment groups with regard to increased (>or=0.5 mg/dl) serum creatinine concentrations after 30-60 days (4.8%, 5.1%, and 3.1%, respectively; P=0.700). Analyses of long-term follow-up (range 63 to 1316 days) by Cox regressions models of the study groups found quite similar survival rates (P=0.500). In contrast to other (retrospective) studies, long-term survival of patients with vs those without CIN within 72 h was not different, but patients who still had elevated creatinine concentrations at 30-60 days suffered from a markedly higher 2-year mortality (46% vs 17%, P=0.002). In conclusion, hemodialysis in addition to hydration therapy for the prevention of CIN provided no evidence for any outcome benefit but evidence for probable harm. Increased creatinine concentrations at 30-60 days, but not within 72 h, were associated with markedly reduced long-term survival.

  7. Short-Term High-Dose Vitamin E to Prevent Contrast Medium-Induced Acute Kidney Injury in Patients With Chronic Kidney Disease Undergoing Elective Coronary Angiography: A Randomized Placebo-Controlled Trial.

    Science.gov (United States)

    Rezaei, Yousef; Khademvatani, Kamal; Rahimi, Behzad; Khoshfetrat, Mehran; Arjmand, Nasim; Seyyed-Mohammadzad, Mir-Hossein

    2016-03-15

    Contrast medium-induced acute kidney injury (CIAKI) is a leading cause of acquired renal impairment. The effects of antioxidants have been conflicting regarding the prevention of CIAKI. We performed a study of vitamin E use to decrease CIAKI in patients undergoing elective coronary angiography. In a placebo-controlled randomized trial at 2 centers in Iran, 300 patients with chronic kidney disease-defined as estimated glomerular filtration rate vitamin E 12 hours before plus 400 mg vitamin E 2 hours before coronary angiography or to receive placebo. The primary end point was the development of CIAKI, defined as an increase ≥0.5 mg/dL or ≥25% in serum creatinine that peaked within 72 hours. Based on an intention-to-treat analysis, CIAKI developed in 10 (6.7%) and 21 (14.1%) patients in the vitamin E and placebo groups, respectively (P=0.037). Change in white blood cell count from baseline to peak value was greater in the vitamin E group compared with the placebo group (-500 [-1500 to 200] versus 100 [-900 to 600]×10(3)/mL, P=0.001). In multivariate analysis, vitamin E (odds ratio 0.408, 95% CI 0.170-0.982, P=0.045) and baseline Mehran score (odds ratio 1.257, 95% CI 1.007-1.569; P=0.043) predicted CIAKI. Prophylactic short-term high-dose vitamin E combined with 0.9% saline infusion is superior to placebo for prevention of CIAKI in patients undergoing elective coronary angiography. URL: https://www.clinicaltrials.gov/. Unique identifier: NCT02070679. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  8. Aspiration of Barium Contrast

    OpenAIRE

    Fuentes Santos, Cristina; Steen, Bárbara

    2014-01-01

    The aspiration of barium contrast is a rare complication that may occur during studies of the digestive tract. Barium is an inert material that can cause anywhere from an asymptomatic mechanical obstruction to serious symptoms of respiratory distress that can result in patient death. We present the case of a 79-year-old male patient in whom we observed the presence of contrast medium residue in the lung parenchyma as an incidental finding during hospitalization. When the patient’s medical fil...

  9. Signal intensity at unenhanced T1-weighted magnetic resonance in the globus pallidus and dentate nucleus after serial administrations of a macrocyclic gadolinium-based contrast agent in children

    Energy Technology Data Exchange (ETDEWEB)

    Rossi Espagnet, Maria Camilla; Bernardi, Bruno; Figa-Talamanca, Lorenzo [Ospedale Pediatrico Bambino Gesu, IRCCS, Neuroradiology Unit, Imaging Department, Rome (Italy); Pasquini, Luca [Ospedale Pediatrico Bambino Gesu, IRCCS, Neuroradiology Unit, Imaging Department, Rome (Italy); University Sapienza, Neuroradiology Unit, Azienda Ospedaliera Sant' Andrea, Rome (Italy); Toma, Paolo [Ospedale Pediatrico Bambino Gesu, IRCCS, Department of Imaging, Rome (Italy); Napolitano, Antonio [Ospedale Pediatrico Bambino Gesu, IRCCS, Enterprise Risk Management, Medical Physics Department, Rome (Italy)

    2017-09-15

    Few studies have been conducted on the relations between T1-weighted signal intensity changes in the pediatric brain following gadolinium-based contrast agent (GBCA) exposure. The purpose of this study is to investigate the effect of multiple administrations of a macrocyclic GBCA on signal intensity in the globus pallidus and dentate nucleus of the pediatric brain on unenhanced T1-weighted MR images. This retrospective study included 50 patients, mean age: 8 years (standard deviation: 4.8 years), with normal renal function exposed to ≥6 administrations of the same macrocyclic GBCA (gadoterate meglumine) and a control group of 59 age-matched GBCA-naive patients. The globus pallidus-to-thalamus signal intensity ratio and dentate nucleus-to-pons signal intensity ratio were calculated from unenhanced T1-weighted images for both patients and controls. A mixed linear model was used to evaluate the effects on signal intensity ratios of the number of GBCA administrations, the time interval between administrations, age, radiotherapy and chemotherapy. T-test analyses were performed to compare signal intensity ratio differences between successive administrations and baseline MR signal intensity ratios in patients compared to controls. P-values were considered significant if <0.05. A significant effect of the number of GBCA administrations on relative signal intensities globus pallidus-to-thalamus (F[8]=3.09; P=0.002) and dentate nucleus-to-pons (F[8]=2.36; P=0.021) was found. The relative signal intensities were higher at last MR examination than at baseline (P<0.001). Quantitative analysis evaluation of globus pallidus:thalamus and dentate nucleus:pons of the pediatric brain demonstrated an increase after serial administrations of macrocyclic GBCA. Further research is necessary to fully understand GBCA pharmacokinetic in children. (orig.)

  10. Diagnostic value of three-dimensional fluid-attenuated inversion recovery MR imaging after intratympanic administration of contrast media in Meniere's disease

    International Nuclear Information System (INIS)

    Shi Honglu; Zhang Daogong; Wang Guangbin; Fan Zhaomin; Bai Xue; Guo Lijun; Man Xiaoni

    2012-01-01

    Objective: After intratympanic gadolinium administration through the tympanic membrane, three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI) was performed to evaluate endolymphatic visualization and its diagnostic value in Meniere's disease. Methods: Twenty-four hours after intratympanic gadolinium administration through the tympanic membrane, 19 patients with unilateral Meniere's disease diagnosed clinically underwent 3D-FLAIR and 3D-Balance-FFE imaging at 3.0 T MR scanner. The enhanced imaging of perilymphatic space in bilateral cochlea, vestibular and (or) canal were observed. Scala tympani and scala vestibule of bilateral cochlear basal turn were scored respectively. The enhanced range of bilateral vestibule and the signal intensity ratio (SIR) between the vestibule and the brain stem were measured. Wilcoxon tests and paired t tests were used. Results: The gadolinium appeared in almost all parts of the perilymph in cochlea,vestibular and (or) canal, so the endolymphatic space was clearly visualized on 3D-FLAIR imaging. The score of scala vestibuli between the affected side (3 cases scored 2, 9 cases scored 1, 7 cases scored 0) and the healthy side (15 cases scored 2, 2 cases scored 1, 2 cases scored 0) were significantly different (U=3.090, P<0.05). The area of enhanced vestibular were (5.77 ± 2.33) mm 2 and (8.11 ± 3.32) mm 2 for the affected side and the healthy side, which were significantly different (U=3.090, P<0.05 and t=2.638, P<0.05). Conclusions: According to 3D-Balance-FFE MRI and the enhancement of perilymphatic space, 3D-FLAIR MRI with intratympanic gadolinium injection through the tympanic membrane can be used to show the border between the perilymph and the endolymph and confirm endolymphatic hydrops, thus providing radiographic evidence for the diagnosis of Meniere's disease. (authors)

  11. Contrast media induced acute renal failure in diabetics

    International Nuclear Information System (INIS)

    Rambausek, M.

    1985-01-01

    Dehydration, preexisting renal insufficiency, multiple myeloma and insulin-dependent diabetes mellitus are known risk factors for a radiocontrast medium induced acute renal failure. In 90% of patients with insulin-dependent diabetes mellitus, renal insufficiency and proteinuria, a further detoriation of renal function can be expected after i.v. administration of radiocontrast medium. Recent concepts on the genesis of acute renal failure after radiocontrast medium in multiple myeloma emphasize the role of tubular blocade (tubular precipitation of myeloma protein with contrast medium). In insulin-dependent diabetic patients we found altered carbohydrate composition of urinary Tamm Horsfall Protein (THP), with increased glucose and diminished N-acetyl-neuraminicacid content. This was paralleled by a difference in an in-vitro system of coprecipitation where THP of diabetes triggered more pronounced calcium dependent coprecipitation of contrast medium and albumin. These in-vitro findings might be important for the explanation of the genesis of radiocontrast medium-induced acute renal failure in insulin-dependent diabetes mellitus. (orig.) [de

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

    International Nuclear Information System (INIS)

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

    1985-01-01

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

  13. The use of iodinated and gadolinium contrast media during pregnancy and lactation

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Judith A.W. [St. Bartholomew' s Hospital, Department of Diagnostic Imaging, London (United Kingdom); Thomsen, Henrik S. [Copenhagen University Hospital at Herlev, Department of Diagnostic Radiology 54E2, Herlev (Denmark); Morcos, Sameh K. [Northern General Hospital, Department of Diagnostic Imaging, Sheffield (United Kingdom)

    2005-06-01

    The use of iodinated or gadolinium-based contrast media in pregnant or lactating women often causes concerns in the radiology department because of the principle of not exposing a fetus or neonate to any drugs. Because of the uncertainty about the use of contrast media during pregnancy and lactation, the Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and draw up guidelines. An extensive literature search was carried out and summarized in a report. Based on the limited information available, simple guidelines have been drawn up. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain. Mutagenic and teratogenic effects have not been described after administration of gadolinium or iodinated contrast media. Free iodide in radiographic contrast medium given to the mother has the potential to depress fetal/neonatal thyroid function. Neonatal thyroid function should be checked during the 1st week if iodinated contrast media have been given during pregnancy. No effect on the fetus has been seen after gadolinium contrast media. Only tiny amounts of iodinated or gadolinium-based contrast medium given to a lactating mother reach the milk, and only a minute proportion entering the baby's gut is absorbed. The very small potential risk associated with absorption of contrast medium may be considered insufficient to warrant stopping breast-feeding for 24 h following either iodinated or gadolinium contrast agents. (orig.)

  14. The use of iodinated and gadolinium contrast media during pregnancy and lactation

    International Nuclear Information System (INIS)

    Webb, Judith A.W.; Thomsen, Henrik S.; Morcos, Sameh K.

    2005-01-01

    The use of iodinated or gadolinium-based contrast media in pregnant or lactating women often causes concerns in the radiology department because of the principle of not exposing a fetus or neonate to any drugs. Because of the uncertainty about the use of contrast media during pregnancy and lactation, the Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and draw up guidelines. An extensive literature search was carried out and summarized in a report. Based on the limited information available, simple guidelines have been drawn up. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain. Mutagenic and teratogenic effects have not been described after administration of gadolinium or iodinated contrast media. Free iodide in radiographic contrast medium given to the mother has the potential to depress fetal/neonatal thyroid function. Neonatal thyroid function should be checked during the 1st week if iodinated contrast media have been given during pregnancy. No effect on the fetus has been seen after gadolinium contrast media. Only tiny amounts of iodinated or gadolinium-based contrast medium given to a lactating mother reach the milk, and only a minute proportion entering the baby's gut is absorbed. The very small potential risk associated with absorption of contrast medium may be considered insufficient to warrant stopping breast-feeding for 24 h following either iodinated or gadolinium contrast agents. (orig.)

  15. Adhesive small bowel obstruction: predictive value of oral contrast administration on the need for surgery Obstrucción intestinal adherencial: valor predictivo de la administración precoz de contraste radiológico sobre la necesidad de cirugía

    Directory of Open Access Journals (Sweden)

    J Perea García

    2004-03-01

    Full Text Available Introduction: adhesive small bowel obstruction (SBO is a common cause of hospital admission. Nonoperative management is initially recommended unless there is suspicion of strangulation, but its optimal duration is controversial. The aims of our study was to evaluate the usefulness of radiographic small bowel examination with contrast medium to predict the need for surgery in SBO. Material and methods: this prospective study carried out from January 1999 to December 2001, included 100 patients with clinical and radiological criteria of adhesive SBO. We described the past medical history, as well as clinical picture, blood tests and radiological findings in these patients. Fifty cubic centimeters of 5% barium suspension were given orally, and plain abdominal radiographs were taken at 4, 8, 16, and 24 hours afterwards. A liquid diet was given as soon as the contrast medium appeared in the right colon. Otherwise, surgical intervention was considered based on the outcome of the patient and the criteria of the emergency surgical team. Results: in 70 patients, barium contrast appeared in the right colon, and a liquid diet was tolerated by 69 of them (98.6%. Mean hospitalization time for this group was 43 ± 17 hours. In the remaining 30 patients, no evidence of barium contrast in the right colon was seen, and 25 of them underwent surgery (75%, while the other 5 tolerated a liquid diet. Mean hospitalization time for this second group of patients was 13.8 ± 11 days. Sensitivity, specificity, positive predictive value, and negative predictive value for the absence of contrast medium in the right colon within 24 hours as a predictor of surgery were 93, 96, 98 and 83%, respectively. There was a statistical significant relationship (p Introducción: la obstrucción intestinal adherencial (OIA es una importante causa de ingreso hospitalario. Salvo que exista sospecha de estrangulación, está indicado inicialmente el manejo conservador. No obstante, el

  16. Interactions of ionic and nonionic contrast agents with thrombolytic agents

    International Nuclear Information System (INIS)

    Fareed, J.; Moncada, R.; Scanlon, P.; Hoppensteadt, D.; Huan, X.; Walenga, J.M.

    1987-01-01

    Both the ionic and nonionic intravascular contrast media have been used before and after the administration of thrombolytic agents to evaluate clot lysis during angioplasty and the treatment of myocardial infarction. In experimental animal models, the authors found that the clot lytic efficacy of streptokinase, streptokinase-plasminogen complex, and tissue plasminogen activator (t-PA) is markedly augmented if these agents are administered within 1 hour after the angiographic producers. Furthermore, contrast agents injected after the administration of t-Pa exhibit a synergistic action. In stimulated models administration of one ionic contrast medium (Angiovist, Berlex, Wayne, NJ) and two nonionic contrast agents (Isovue-370, Squibb Diagnostics, New Brunswick, NJ; Omnipaque-350, Winthrop, NY) 15 minutes before the administration of t-PA resulted in marked enhancement of the lytic activity. Although the mechanism of this interaction is unknown at this time, it should be taken into consideration in the treatment of patients with myocardial infarction, in whom contrast agents are continually used to evaluate the therapeutic lysis. Furthermore, this interaction may be partly related to the therapeutic efficacy and/or hemorrhagic actions observed

  17. Iodinated contrast media and patients with high-risk kidneys. Aiming at rational prevention

    International Nuclear Information System (INIS)

    Fontaine, B.; Frouge, C.; Gagey, N.

    1994-01-01

    Acute renal failure induced by iodinated contrast media (CM) accounts for about 10% of all hospital cases of renal failure, especially in azotemic patients. The specific anatomy and physiology of the inner medulla renalis render it particularly sensitive to even a moderate reduction in blood supply. Renal function will be estimated by measuring serum creatinine levels, before and within 72 hours after administration of the iodinated contrast medium. Hypovolaemia, diabetes mellitus-induced microangiopathy, nephrotoxic drugs and especially dehydratation may provoke renal accidents. Proper hydration, choosing a low osmolality medium and adequately spacing exposures to CM are elementary measures to be adopted to prevent renal failure. (authors)

  18. Use of cystatin C and serum creatinine for the diagnosis of contrast-induced nephropathy in patients undergoing contrast-enhanced computed tomography at an oncology centre.

    Directory of Open Access Journals (Sweden)

    Joao Italo Fortalesa Melo

    Full Text Available Our aim was to assess renal function using as laboratory measurements serum creatinine and cystatin C concentrations before and after administration of low-osmolarity (nonionic iodinated contrast medium in patients with cancer undergoing computed tomography (CT.This prospective study included 400 oncologic outpatients. Serum creatinine and cystatin C concentrations were measured before and 72 h after contrast administration. Glomerular filtration rates (GFRs were estimated using serum creatinine-based [Modification of Diet in Renal Disease (MDRD and Cockroft-Gault and cystatin C based (Larsson equations. Exploratory data analysis was performed. The nonparametric Wilcoxon test was used to compare pre and post contrast of test results and estimated clearance. The confidence interval used in the analysis was 95%.Compared with the pre-contrast values, the mean serum creatinine concentration was significantly higher and average GFRs estimated using MDRD and Cockcroft-Gault equations were significantly lower after the administration of contrast (p <0.001. It was also observed a significant increase after contrast in the concentration of Cystatin C (p = 0.015. In addition, a decrease in GFR estimated using the average Larsson (p = 0.021 was observed between time points. However, none of the patients presented clinically significant nephropathy.Assessment using serum creatinine and cystatin C concentrations showed changes in renal function among patients with cancer undergoing contrast-enhanced CT examination in this study. No significant renal damage related to the use of low-osmolarity iodinated contrast medium of the type and dosage employed in this study was observed. This contrast medium is thus safe for use in patients with cancer.

  19. In Vivo Differentiation of Complementary Contrast Media at Dual-Energy CT

    Science.gov (United States)

    Mongan, John; Rathnayake, Samira; Fu, Yanjun; Wang, Runtang; Jones, Ella F.; Gao, Dong-Wei

    2012-01-01

    Purpose: To evaluate the feasibility of using a commercially available clinical dual-energy computed tomographic (CT) scanner to differentiate the in vivo enhancement due to two simultaneously administered contrast media with complementary x-ray attenuation ratios. Materials and Methods: Approval from the institutional animal care and use committee was obtained, and National Institutes of Health guidelines for the care and use of laboratory animals were observed. Dual-energy CT was performed in a set of iodine and tungsten solution phantoms and in a rabbit in which iodinated intravenous and bismuth subsalicylate oral contrast media were administered. In addition, a second rabbit was studied after intravenous administration of iodinated and tungsten cluster contrast media. Images were processed to produce virtual monochromatic images that simulated the appearance of conventional single-energy scans, as well as material decomposition images that separate the attenuation due to each contrast medium. Results: Clear separation of each of the contrast media pairs was seen in the phantom and in both in vivo animal models. Separation of bowel lumen from vascular contrast medium allowed visualization of bowel wall enhancement that was obscured by intraluminal bowel contrast medium on conventional CT scans. Separation of two vascular contrast media in different vascular phases enabled acquisition of a perfectly coregistered CT angiogram and venous phase–enhanced CT scan simultaneously in a single examination. Conclusion: Commercially available clinical dual-energy CT scanners can help differentiate the enhancement of selected pairs of complementary contrast media in vivo. © RSNA, 2012 PMID:22778447

  20. Radiographic, MR or ultrasound contrast media in pregnant or breast-feeding women. What are the key issues?

    International Nuclear Information System (INIS)

    Froehlich, J.M.; Kubik-Huch, Rahel A.

    2013-01-01

    The use and the safety of radiographic, MR- or ultrasound contrast media in the diagnostic work-up of pregnant or lactating patients is a frequently discussed question. As only sparse clinical data is available, a careful benefit-risk assessment must contain physico-chemical properties, preclinical data including teratogeneity and embryotoxicity, as well as maternal and foetal exposure. With consideration to the individual risks, iodinated contrast media, macrocyclic MR contrast media with increased stability or sulphur hexafluoride ultrasound contrast media may, if clinically justified, be administered in the smallest possible doses throughout pregnancy. After parental administration of an iodinated contrast medium after the 12th week of pregnancy, the neonate's thyroidal function should be checked during the first week after birth. After parental administration of iodinated, stable macrocyclic, gadolinium or ultrasound contrast media, lactation can be continued normally. In any case, contrast media should be used with caution and only if the benefits outweigh the risk. (orig.)

  1. Aspiration of Barium Contrast

    Directory of Open Access Journals (Sweden)

    Cristina Fuentes Santos

    2014-01-01

    Full Text Available The aspiration of barium contrast is a rare complication that may occur during studies of the digestive tract. Barium is an inert material that can cause anywhere from an asymptomatic mechanical obstruction to serious symptoms of respiratory distress that can result in patient death. We present the case of a 79-year-old male patient in whom we observed the presence of contrast medium residue in the lung parenchyma as an incidental finding during hospitalization. When the patient’s medical file was reviewed, images were found of a barium swallow study that the patient had undergone months earlier, and we were able to observe the exact moment of the aspiration of the contrast material. The patient had been asymptomatic since the test.

  2. Local recurrence of rectal cancer: MR imaging before and after oral superparamagnetic particles vs contrast-enhanced computed tomography

    International Nuclear Information System (INIS)

    Blomqvist, L.; Ohlsen, H.; Holm, T.

    2000-01-01

    The aim of this study was to compare three imaging strategies for the diagnosis of local recurrence of rectal cancer: (a) MR imaging; (b) MR imaging after administration of enteral superparamagnetic particles (Ferristene); and (c) contrast-enhanced CT. Seventeen patients with previous surgery for rectal cancer were examined, 12 patients with local tumour recurrence in the pelvis and 5 patients with postoperative changes. Pelvic multi-coil MR imaging before and after oral administration of superparamagnetic contrast medium [Abdoscan (Ferristene USAN), Nycomed-Amersham, Lidingoe, Sweden] as well as abdominal and pelvic CT was performed in all patients. The examinations were independently evaluated by three different radiologists. The general effect of the oral MR contrast medium, the delineation of normal and pathological structures as well as confidence in the diagnosis were registered on a visual analog scale (VAS). The diagnosis according to MR before and after oral contrast medium, and CT, was compared, in 16 patients, with the final diagnosis which was verified by biopsy (n = 3), surgery (n = 6), clinical follow-up (n = 4) and by follow-up with MR or CT (n = 3). No significant improvement in MR image quality was found after enteral contrast medium. The post-contrast MR diagnosis was not changed in any of the patients. The diagnosis on MR correlated with the final diagnosis in 12 of 16 patients (sensitivity 91 %, accuracy 62 %) and the diagnosis on CT in 11 of 16 patients (sensitivity 82 %, accuracy 56 %). The radiologists' ''confidence'' in the diagnosis and the degree of accordance with the final diagnosis did not score higher on MR after than before oral contrast administration; however, the accordance with the final diagnosis scored better on MR than on CT. No advantages of orally administered superparamagnetic contrast medium were observed in the examined patient group. Magnetic resonance is preferable to CT in diagnosing local tumour recurrence. (orig.)

  3. Contrast-enhanced magnetic resonance imaging of tumours of the central nervous systems: a clinical review

    International Nuclear Information System (INIS)

    Graif, M.; Steiner, R.E.

    1986-01-01

    The clinical application of the intravascular paramagnetic contrast agent gadolinium-DTPA for magnetic resonance imaging (MRI) imaging of tumours of the central nervous system (CNS) has been assessed over the past 3 years. Various patterns of contrast enhancement were observed, and situations in MRI where the administration of contrast medium may be useful have been defined. These include lesions which are isointense with normal brain matter, the separation of tumour from surrounding oedema, evaluation of the degree of blood-brain barrier breakdown, delineation of tumours obscured by overlying calcification on computed tomography (CT) and in the investigation of lesions in anatomical areas where CT has known limitations (brain, stem, cervical spine). Changes in relaxation times in normal and abnormal tissues following contrast medium, toxicity and dosage of gadolinium-DTPA, and MRI pulse sequence techniques are reviewed. (author)

  4. Contrast media

    International Nuclear Information System (INIS)

    Decazes, Ph.

    2004-01-01

    The Guerbet firm, which holds 69% of the capital on the contrast media for medical imagery, could sale about 20% of this capital in order to accelerate its development in the United States, one of its next market with the Japan. (O.M.)

  5. Technique of application of contrast media in computed tomography of the heart

    International Nuclear Information System (INIS)

    Heuser, L.; Friedmann, G.

    1982-01-01

    Cardiac imaging by means of CT requires administration of intravenous contrast medium which can be applied by infusion or by rapid bolus injection. Contrast infusion is easier in performance and yields opacification of all cardiac cavities. Using bolus technique selective enhancement of cardiac chambers can be obtained which provides increased image quality and better resolution of cardiac structures. Both techniques are described and the results of 221 examinations are analysed with special respect to image quality, technical amount and contrast media side effects. (orig.) [de

  6. Contrast bolus technique with rapid CT scanning

    International Nuclear Information System (INIS)

    Arnold, H.; Kuehne, D.; Rohr, W.; Heller, M.

    1981-01-01

    Twenty-three patients complying with the clinical criteria for brain death were studied by contrast-enhanced CT. In all but one, the great intracranial vessels escaped visualization; accordingly, angiography demonstrated cerebral circulatory arrest. In the remaining case, faint enhancement of the circle of Willis corresponded to angiographic demonstration of the proximal segments of cerebral arteris. Neither in normal brain nor in dead brain did slow CT scanning disclose any postcontrast increase in parenchymal attenuation. An improved technique is proposed to demonstrate the transit of the contrast bolus by rapid CT with image splitting. If cerebral blood flow is preserved, the grey and white matter will enhance significantly following administration of contrast medium. Vice versa, the absence of enhancement confirms brain death, even in instances in which the great cerebral vessels are obscured by hemorrhage or other extensive lesions. Two additional cases of brain death were evaluated by rapid CT scanning. As to brain death, the technique obviates the need for angiography or radionuclide angiography, usually applied in prospective organ donors, because its informative content is superior to that of either method. The CT technique described affords a reliable and safe diagnosis of brain death, and can be interpreted easily. (orig.)

  7. Nephrotoxicity of cyclosporin A and contrast media

    International Nuclear Information System (INIS)

    Thomsen, H.S.; Larsen, S.; Skaarup, P.; Hemmingsen, L.; Dieperink, H.; Golman, K.; Herlev Hospital; Herlev Hospital; Centralsygehuset, Nykoebing Falster; Odense Sygehus; Malmoe Allmaenna Sjukhus

    1989-01-01

    Urine profiles (albumin, glucose, NAG, LDH, GGT and sodium) were followed for 22 h or 8 days after intravenous injection of diatrizoate, iohexol or saline in 30 adult Wistar rats in which nephrotoxicity was induced by daily peroral administration of 25 mg/kg body weight cyclosporin A over a 14-day period. Another 10 rats which had the vehicle of the cyclosporin A solution (placebo) and saline injected intravenously served as controls. The effect of iohexol and saline on the albumin excretion was similar, whereas diatrizoate increased it significantly. Both contrast media caused significantly increased excretion of all three enzymes. The contrast media had no effect on the excretion of glucose and sodium. Except for the fact that the excretion of NAG was significantly higher following iohexol than following diatrizoate 24 to 46 h after injection no significant differences between the two media were found from 24 h after injection among the rats given cyclosporin A. No contrast medium related changes were found by light microscopy of the kidneys. Neither iohexol nor diatrizoate potentiate acute cyclosporin A nephrotoxicity. (orig.)

  8. Indirect caudal lymphography using a new water-soluble contrast agent - animal experimental studies in pigs

    International Nuclear Information System (INIS)

    Apitzsch, D.E.; Kroll, H.U.; Zuehlke, H.V.

    1981-01-01

    Animal experiments on caudal lymphography in pigs are presented, using a new water-soluble contrast medium which is renally excreted. Indirect cutaneous administration renders possible the radiological visualization of the entire lymphatic drainage system of the lower limb, the retro-peritoneal space and the thoracic duct. Visualization of the lymphatic system is rapid, homogeneous and can be repeated as often as desired. The quality of the lymphogram is as good as that obtained by the current methods in common use. (orig.)

  9. Depiction of normal gastrointestinal anatomy with MDCT: comparison of low- and high-attenuation oral contrast media.

    Science.gov (United States)

    Erturk, Sukru Mehmet; Mortelé, Koenraad J; Oliva, Maria-Raquel; Ichikawa, Tomoaki; Silverman, Stuart G; Cantisani, Vito; Pagliara, Elisa; Ros, Pablo R

    2008-04-01

    To compare low- and high-attenuation oral contrast media for depiction of normal gastrointestinal anatomy with multidetector-row computed tomography (MDCT). A prospective, randomized study of 90 consecutive patients without known or suspected gastrointestinal disease was conducted after the approval of our Institutional Review Board. All patients underwent IV contrast-enhanced abdominal and pelvic CT scans after oral administration of 900 ml of either low- or high-attenuation barium sulphate suspension. Using a five-point scale, two radiologists independently graded distention and wall visualization of stomach, duodenum, jejunum, and ileum. The degree of distention and wall visualization was compared using Mann-Whitney U-test. Duodenal, jejunal and ileal distention (pcontrast medium were significantly higher than those with high-attenuation barium sulphate preparation, for reader 1. Duodenal and jejunal wall visualization scores with low-attenuation contrast medium (pcontrast medium, for reader 2. Interobserver agreement was fair to good for both distention (kappa-range: 0.41-0.74) and wall visualization (kappa-range: 0.48-0.71). MDCT with low-attenuation contrast medium provides distention and wall visualization of the GI tract that is equal or better than high-attenuation contrast medium.

  10. Contrast media on abdominal computed tomography

    International Nuclear Information System (INIS)

    Skalpe, I.O.; Oestensen, H.M.

    1984-01-01

    Abdominal computed tomography was performed in 55 patients before and after intravenous injection of 60 ml of a non-ionic (iohexol) or an ionic (metrizoate) contrast medium. The adverse effects were recorded and a series of measurements of attenuation values before and after the contrast medium injection was performed in the aorta and in hepatic and renal parenchyma. Only minor adverse effects were seen with both contrast media, but iohexol was clearly better tolerated than metrizoate. No difference in the enhancement properties was found between the two contrast media. (orig.)

  11. Intravenous contrast media application using cone-beam computed tomography in a rabbit model

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Sung; Kim, Bok Yeol; Choi, Hwa Young [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Kyung Hee University, Seoul (Korea, Republic of); and others

    2015-03-15

    This study was performed to evaluate the feasibility of visualizing soft tissue lesions and vascular structures using contrast-enhanced cone-beam computed tomography (CE-CBCT) after the intravenous administration of a contrast medium in an animal model. CBCT was performed on six rabbits after a contrast medium was administered using an injection dose of 2 mL/kg body weight and an injection rate of 1 mL/s via the ear vein or femoral vein under general anesthesia. Artificial soft tissue lesions were created through the transplantation of autologous fatty tissue into the salivary gland. Volume rendering reconstruction, maximum intensity projection, and multiplanar reconstruction images were reconstructed and evaluated in order to visualize soft tissue contrast and vascular structures. The contrast enhancement of soft tissue was possible using all contrast medium injection parameters. An adequate contrast medium injection parameter for facilitating effective CE-CBCT was a 5-mL injection before exposure combined with a continuous 5-mL injection during scanning. Artificial soft tissue lesions were successfully created in the animals. The CE-CBCT images demonstrated adequate opacification of the soft tissues and vascular structures. Despite limited soft tissue resolution, the opacification of vascular structures was observed and artificial soft tissue lesions were visualized with sufficient contrast to the surrounding structures. The vascular structures and soft tissue lesions appeared well delineated in the CE-CBCT images, which was probably due to the superior spatial resolution of CE-CBCT compared to other techniques, such as multislice computed tomography.

  12. Intravenous contrast media application using cone-beam computed tomography in a rabbit model

    International Nuclear Information System (INIS)

    Kim, Min Sung; Kim, Bok Yeol; Choi, Hwa Young

    2015-01-01

    This study was performed to evaluate the feasibility of visualizing soft tissue lesions and vascular structures using contrast-enhanced cone-beam computed tomography (CE-CBCT) after the intravenous administration of a contrast medium in an animal model. CBCT was performed on six rabbits after a contrast medium was administered using an injection dose of 2 mL/kg body weight and an injection rate of 1 mL/s via the ear vein or femoral vein under general anesthesia. Artificial soft tissue lesions were created through the transplantation of autologous fatty tissue into the salivary gland. Volume rendering reconstruction, maximum intensity projection, and multiplanar reconstruction images were reconstructed and evaluated in order to visualize soft tissue contrast and vascular structures. The contrast enhancement of soft tissue was possible using all contrast medium injection parameters. An adequate contrast medium injection parameter for facilitating effective CE-CBCT was a 5-mL injection before exposure combined with a continuous 5-mL injection during scanning. Artificial soft tissue lesions were successfully created in the animals. The CE-CBCT images demonstrated adequate opacification of the soft tissues and vascular structures. Despite limited soft tissue resolution, the opacification of vascular structures was observed and artificial soft tissue lesions were visualized with sufficient contrast to the surrounding structures. The vascular structures and soft tissue lesions appeared well delineated in the CE-CBCT images, which was probably due to the superior spatial resolution of CE-CBCT compared to other techniques, such as multislice computed tomography.

  13. Sharing perspectives on English-medium instruction

    CERN Document Server

    Ackerley, Katherine; Helm, Francesca

    2017-01-01

    This volume gives voice to the views and experiences of researchers, lecturers, administrative staff, teacher trainers and students with regard to the implementation of English-medium instruction in a public university based in the north-east of Italy.

  14. Comparison of Gastrografin to barium sulfate as a gastrointestinal contrast agent in red-eared slider turtles (Trachemys scripta elegans).

    Science.gov (United States)

    Long, Charles Tyler; Page, Richard B; Howard, Antwain M; McKeon, Gabriel P; Felt, Stephen A

    2010-01-01

    Red-eared slider turtles (Trachemys scripta elegans) commonly develop intestinal obstruction. The gastrointestinal transit time in turtles tends to be longer than in other animals, making a rapid diagnosis of obstruction difficult. Fifteen red-eared sliders were given either Gastrografin or 30% w/v barium sulfate orally to compare ease of administration, transit time, and image quality. Each contrast medium was easy to administer but barium sulfate had to be administered more slowly (mean = 40s) than Gastrografin (mean = 20s) to prevent regurgitation. The mean transit and emptying time of Gastrografin was at least 9 h faster than barium sulfate at all time points except gastric transit. Both contrast media had a smooth, uniform appearance that outlined the mucosa with well-defined margins within the stomach and proximal small intestine. Dilution of Gastrografin occurred as it progressed through the intestines, resulting in decreased opacity in the distal small intestine and colon. Pre-administration packed cell volume and total serum protein levels of four turtles receiving Gastrografin were compared with levels at 24-, 96-, and 168-hours postadministration as well as to four control turtles not receiving contrast medium. Packed cell volume and total serum protein levels did not significantly differ among the Gastrografin and control group. From a clinical perspective, administration of Gastrografin allows for quicker results with only minor hematologic changes in red-eared sliders, but visualization of this contrast medium in the lower gastrointestinal tract may be insufficient for an accurate diagnosis.

  15. Iodinated contrast media nephrotoxicity

    International Nuclear Information System (INIS)

    Meyrier, A.

    1994-01-01

    In the late seventies, iodinated contrast agents (ICA) were considered to be a major cause of acute iatrogenic renal failure. Over the last decade new contrast agents have been synthesized, nonionic and less hyperosmolar. The incidence of acute renal failure due to ICAs, varies from 3.7 to 70% of cases according to the series, with an average figure of 10.2%. The pathophysiology of ICA nephrotoxicity was mainly studied in laboratory animal models. Three main factors are involved in an inducing ICA-mediated decrease in glomerular filtration rate: reduction of the renal plasma flow, a direct cytotoxic effect on renal tubular cells and erythrocyte alteration leading to intra-renal sludge. Excluding dysglobulinemias with urinary excretion of immunoglobulin light chains, which represent a special case of maximum nephrotoxicity, 4 main risk factors of renal toxicity have been identified in nondiabetic subjects: previous renal failure with serum creatinine levels greater than 140 μmol per liter, extracellular dehydration, age over 60 and use of high doses of ICA and/or repeated ICA injections before serum creatinine levels return to baseline. Preventive measures for avoiding ICA nephrotoxicity are threefold: maintain or restore adequate hydration with saline infusion, stop NSAID treatment several days before ICA administration, and allow a 5 day interval before repeating contrast media injections. New, nonionic and moderately hyperosmolar contrast agents appear to be much less nephrotoxic than conventional ICAs in laboratory animals and in high-risk patients. It is advisable to select such contrast media for investigating high-risk patients. This approach was recently substantiated in well designed, randomized clinical studies which included more than 2 000 patients. (author)

  16. Quantitative analysis of contrast enhancement of transplanted kidneys under computed tomography

    International Nuclear Information System (INIS)

    Fujita, Tamio; Asano, Haruyoshi; Yanaoka, Masanori; Moriguchi, Ryuichiro; Okishio, Norihiko

    1981-01-01

    Using Hitachi CT-3, the changes in CT numbers of the kidney were calculated in 10 normal and 12 transplanted kidneys. Two mililiters per kg of meglumine diatrizoate (Angiografin) was given intravenously in bolus fashion. Kidneys were scanned before injection, at termination of injection and correctly 10 minutes after injection. In control group, the CT numbers of the cortex, the medulla and the aorta showed rapid increase after contrast administration. Ten minutes after administration of medium, the CT numbers of the medulla remained a little higher than the cortex, though that of the aorta showed rapid decrease. In contrast to control group, in transplanted kidneys the CT numbers of the cortex and medulla showed less increase than the control group just after contrast administration. Moreover, in the recipients who have had good graft function the CT numbers of the cortex and medulla showed gradual increase, in the recipients who have had poor graft function the CT numbers showed gradual decrease 10 minutes after injection. Enhancing indices calculated from the formula: CT numbers 10 minutes after contrast enhancement CT numbers before contrast enhancement were inversely proportional to the serum creatinine. These results lead to the conclusion that the CT scans employing contrast enhancement method after kidney transplantation has the diagnostic value of graft function in addition to diagnostic usefulness for post-transplantation complications such as hematoma, urinoma or lymphocele. (author)

  17. Radiation absorption, water content and contrast medium impregnation of gallstones

    International Nuclear Information System (INIS)

    Schmitt, W.G.H.

    1982-01-01

    Gallstones extracted by surgery were examined for CT density, which was compared with the X-ray film, floating performance and chemical analysis of the stones. So far, the water content of the biliary concrements - 14% on the average - has not been given much attention. Drying will considerably reduce the density; examination of the dried gallstones yields a false picture of direct ray absorption. Pure cholesterol stones do not float in water, and they show positive values on Hounsfield's scale (+30 - +60). The article discusses the question whether CT is suitable for effecting a better selection of gallstone patients who can be treated by drug therapy. (orig.) [de

  18. Adriamycin nephrosis and contrast media

    International Nuclear Information System (INIS)

    Thomsen, H.S.; Golman, K.; Hemmingsen, L.; Larsen, S.; Skaarup, P.; Koebenhavns Amts Sygehus, Herlev; Koebenhavns Amts Sygehus, Herlev; Centralsygehuset, Nykoebing Falster; Malmoe Allmaenna Sjukhus

    1990-01-01

    Urine profiles (albumin, glucose, NAG, LDH, GGT and sodium) were followed for 9 days after intravenous injection of either diatrizoate, iohexol, or saline in 27 Wistar rats with nephrosis induced by Adriamycin 42 days before. Another 9 rats exposed to neither Adriamycin nor contrast media served as controls. None of the contrast media caused further increased albuminuria of significance, whereas both induced significantly increased excretion of all 5 tubular components. The excretion of NAG and sodium was significantly higher following diatrizoate than following iohexol. From 24 h post injection there was no significantly greater excretion of any of the components after either diatrizoate or iohexol than after saline among the rats given Adriamycin. At the end of day 9 after contrast medium injection neither serum sodium, potassium, glucose, urea, creatinine, nor albumin revealed any contrast media related changes. Kidney histology showed quantitatively larger lesions in kidneys exposed to Adriamycin and contrast media than in kidneys exposed to Adriamycin and saline. There were no differences between the two contrast media groups. It is thus concluded, that both high osmolar ionic and low osmolar non-ionic contrast media cause temporary tubular dysfunction but no further glomerular dysfunction in rats with nephrosis induced by Adriamycin. The histologic findings indicate that both media may worsen non-reversible renal lesions. (orig.)

  19. Safe Use of Contrast Media: What the Radiologist Needs to Know.

    Science.gov (United States)

    Beckett, Katrina R; Moriarity, Andrew K; Langer, Jessica M

    2015-10-01

    Iodinated and gadolinium-based contrast media are used on a daily basis in most radiology practices. These agents often are essential to providing accurate diagnoses, and are nearly always safe and effective when administered correctly. However, reactions to contrast media do occur and can be life threatening. Therefore, it is critical for faculty and staff to know how reactions to contrast agents manifest and how to treat them promptly. The decline in renal function seen occasionally after intravenous administration of iodinated contrast agents is poorly understood and likely multifactorial, and its association with the contrast medium may be overemphasized. However, it is important that radiologists be aware of current understanding and strategies to decrease the incidence of renal dysfunction. Nephrogenic systemic fibrosis, a skin disease, is an adverse reaction related to use of some gadolinium-based contrast agents in patients with chronic renal failure. The types of gadolinium most often associated with this condition and the indications for withholding gadolinium are important and are discussed in this article. The use of enteric contrast agents and contrast agents during pregnancy and nursing are reviewed briefly. Current knowledge for safe use of contrast media and key concepts that all radiologists should know are summarized in this review. © RSNA, 2015.

  20. Pro Linux System Administration

    CERN Document Server

    Turnbull, James

    2009-01-01

    We can all be Linux experts, provided we invest the time in learning the craft of Linux administration. Pro Linux System Administration makes it easy for small to medium--sized businesses to enter the world of zero--cost software running on Linux and covers all the distros you might want to use, including Red Hat, Ubuntu, Debian, and CentOS. Authors, and systems infrastructure experts James Turnbull, Peter Lieverdink, and Dennis Matotek take a layered, component--based approach to open source business systems, while training system administrators as the builders of business infrastructure. If

  1. Depiction of normal gastrointestinal anatomy with MDCT: Comparison of low- and high-attenuation oral contrast media

    International Nuclear Information System (INIS)

    Erturk, Sukru Mehmet; Mortele, Koenraad J.; Oliva, Maria-Raquel; Ichikawa, Tomoaki; Silverman, Stuart G.; Cantisani, Vito; Pagliara, Elisa; Ros, Pablo R.

    2008-01-01

    Purpose: To compare low- and high-attenuation oral contrast media for depiction of normal gastrointestinal anatomy with multidetector-row computed tomography (MDCT). Materials and methods: A prospective, randomized study of 90 consecutive patients without known or suspected gastrointestinal disease was conducted after the approval of our Institutional Review Board. All patients underwent IV contrast-enhanced abdominal and pelvic CT scans after oral administration of 900 ml of either low- or high-attenuation barium sulphate suspension. Using a five-point scale, two radiologists independently graded distention and wall visualization of stomach, duodenum, jejunum, and ileum. The degree of distention and wall visualization was compared using Mann-Whitney U-test. Results: Duodenal, jejunal and ileal distention (p < 0.05, <0.001, <0.001, respectively) and wall visualization (p < 0.05, <0.01, <0.05, respectively) scores with low-attenuation contrast medium were significantly higher than those with high-attenuation barium sulphate preparation, for reader 1. Duodenal and jejunal wall visualization scores with low-attenuation contrast medium (p < 0.05, <0.01, respectively) were significantly higher than those with high-attenuation contrast medium, for reader 2. Interobserver agreement was fair to good for both distention (κ-range: 0.41-0.74) and wall visualization (κ-range: 0.48-0.71). Conclusion: MDCT with low-attenuation contrast medium provides distention and wall visualization of the GI tract that is equal or better than high-attenuation contrast medium

  2. Internationalization of Small and Medium Enterprises in High Impact Factor Administration Journals: 2000-2008Http://Dx.Doi.Org/10.5585/Riae.V9i3.1692

    Directory of Open Access Journals (Sweden)

    Giancarlo Gomes

    2011-01-01

    Full Text Available The article analyzed the scientific output of the Internationalization of Small and Medium Enterprises (SME within four international journals between 2000-2008, through: exploratory research; qualitative methods; documentary analysis; and purposeful sampling. 26 articles were analyzed, considering their research objectives, theoretical frameworks, adopted methodologies and their principal contributions to the subject. It was acknowledged that these papers aspired to understand, analyze, interpret and identify the reasons and importance of the internationalization of SME. The Uppsala model was referenced in a number of polls, and principally presented the quantitative method. The main topics discussed were: the importance of social capital and networks in their internationalization and global alliances; management skills and personal skills of managers; distribution channels; the relationship between performance and size of the international organization; in addition to the role of experience abroad.

  3. Effect of contrast media iodine concentration on bolus tracking

    International Nuclear Information System (INIS)

    Ishihara, Toshihiro; Hayashi, Takayuki; Nakaya, Yoshihiro; Naoi, Kuniji; Ikeno, Naoya; Kobayashi, Tatsushi; Satake, Mitsuo

    2006-01-01

    Computer-assisted bolus tracking has been confirmed to be a useful technique in computed tomography (CT) imaging and allows images to be captured with automated timing. The inflow of the contrast medium is monitored, and when the contrast medium reaches a predetermined level, CT image capture starts automatically. However, it has been shown that the preset threshold value of contrast medium is affected by its iodine concentration, which causes variations in image capture times. Greater speed in current multislice CT imaging requires that medical technicians pay more attention to setting the timing of image capture during venous examinations by taking into account the iodine concentration in contrast media. (author)

  4. Development of low-dose photon-counting contrast-enhanced tomosynthesis with spectral imaging.

    Science.gov (United States)

    Schmitzberger, Florian F; Fallenberg, Eva Maria; Lawaczeck, Rüdiger; Hemmendorff, Magnus; Moa, Elin; Danielsson, Mats; Bick, Ulrich; Diekmann, Susanne; Pöllinger, Alexander; Engelken, Florian J; Diekmann, Felix

    2011-05-01

    To demonstrate the feasibility of low-dose photon-counting tomosynthesis in combination with a contrast agent (contrast material-enhanced tomographic mammography) for the differentiation of breast cancer. All studies were approved by the institutional review board, and all patients provided written informed consent. A phantom model with wells of iodinated contrast material (3 mg of iodine per milliliter) 1, 2, 5, 10, and 15 mm in diameter was assessed. Nine patients with malignant lesions and one with a high-risk lesion (atypical papilloma) were included (all women; mean age, 60.7 years). A multislit photon-counting tomosynthesis system was utilized (spectral imaging) to produce both low- and high-energy tomographic data (below and above the k edge of iodine, respectively) in a single scan, which allowed for dual-energy visualization of iodine. Images were obtained prior to contrast material administration and 120 and 480 seconds after contrast material administration. Four readers independently assessed the images along with conventional mammograms, ultrasonographic images, and magnetic resonance images. Glandular dose was estimated. Contrast agent was visible in the phantom model with simulated spherical tumor diameters as small as 5 mm. The average glandular dose was measured as 0.42 mGy per complete spectral imaging tomosynthesis scan of one breast. Because there were three time points (prior to contrast medium administration and 120 and 480 seconds after contrast medium administration), this resulted in a total dose of 1.26 mGy for the whole procedure in the breast with the abnormality. Seven of 10 cases were categorized as Breast Imaging Reporting and Data System score of 4 or higher by all four readers when reviewing spectral images in combination with mammograms. One lesion near the chest wall was not captured on the spectral image because of a positioning problem. The use of contrast-enhanced tomographic mammography has been demonstrated successfully in

  5. Contrast detail phantom for SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Cabrejas, M.L. de; Arashiro, J G; Giannone, C. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Camuyrano, M; Nohara, G [Universidad de Buenos Aires, Buenos Aires (Argentina). Facultad Ciencias Exactas

    1996-06-01

    A new low variable contrast phantom for single photon emission computed tomography (SPECT) was constructed, tested and compared with other existing phantoms. It contains simulated cylindrical lesions of four different diameters (D{sub i}), embedded in a cylindrical scattering medium and a uniform section to evaluate tomographic uniformity. The concentration of tracer in the simulated lesions and the scattering medium (background) can be varied to simulate hot and cold lesions. Different applications of the phantom were tested, including determination of the minimum object contrast (OCm) necessary to detect lesions as a function of lesion size, lesion type (hot or cold) and acquisition and processing protocols by visual inspection. This parameter allows categorization of instruments comparing an `image quality index` (IQI). Preliminary comparison with the Britten contrast processing method showed that the detectable OCm was of the same order of magnitude, but the presented device seems more suitable for training and intercomparison purposes. The constructed phantom, of simple design, has proved to be useful for acquisition and processing condition evaluation, OCm estimation and external quality control. (author). 11 refs, 4 figs.

  6. Development of contrast media

    International Nuclear Information System (INIS)

    Krause, W.

    1993-01-01

    Description of all contrast media (ionic and nonionic monomers, ionic and nonionic dimers) was presented. Chemotoxicity, osmolality and viscosity of some contrast agents were analyzed. The main adverse reactions to ionic and nonionic contrast media were described

  7. Hypersensitivity to contrast media and dyes.

    Science.gov (United States)

    Brockow, Knut; Sánchez-Borges, Mario

    2014-08-01

    This article updates current knowledge on hypersensitivity reactions to diagnostic contrast media and dyes. After application of a single iodinated radiocontrast medium (RCM), gadolinium-based contrast medium, fluorescein, or a blue dye, a hypersensitivity reaction is not a common finding; however, because of the high and still increasing frequency of those procedures, patients who have experienced severe reactions are nevertheless frequently encountered in allergy departments. Evidence on allergologic testing and management is best for iodinated RCM, limited for blue dyes, and insufficient for fluorescein. Skin tests can be helpful in the diagnosis of patients with hypersensitivity reactions to these compounds. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Contrast media in computed tomography of the mediastinum and the lung

    International Nuclear Information System (INIS)

    Wegener, O.-H.; Claussen, C.D.

    1981-01-01

    An administration of contrast medium is frequently indicated for problems of mediastinal diagnosis. The reason for this is that previous diagnosis or a clear set of clinical symptoms justifies the suspicion of a space-occupying process. Moreover, CT should lead to diagnoses which are as definite and differentiated as possible. In the majority of examinations, contrast media should be applied to evaluate the mediastinum. Infusion technique is suitable for extensive or disseminated processes, whereby the dose depends on the duration of the examination. An intravasal enhancement exceeding 60 Hounsfield Units (HU) should be achieved for the entire period. For focal lesions bolus injections should be used to clarify the degree of vascularization of the expected process. Besides site and radiodensity, it is the degree of vascularization that narrows down the differential diagnosis in mediastinal disease. At present an indication for application of contrast media in lung diseases does not exist. (Auth.)

  9. Addition of lacal anesthetics to contrast media. Pt. 2

    International Nuclear Information System (INIS)

    Nilsson, P.; Almen, T.; Golman, K.; Jonsson, K.; Nyman, U.; Malmoe Allmaenna Sjukhus

    1988-01-01

    The acute intravenous toxicity (i.v. LD 50 ) of solutions of the ratio 1.5 contrast media metrizoate or diatrizoate and the ratio 3.0 contrast medium metrizamide was determined in mice with and without the addition of local anesthetics to the solutions. The two local anesthetics mepivacaine or lidocaine were added to final concentrations up to 2.0 mg/ml of the contrast medium solutions. This corresponds to clinically used concentrations. All additions of local anesthetics to the solutions increased the mortalities caused by the contrast medium solutions. Addition of local anesthetics to a final concentration of 2 mg/ml approximately doubled the acute intravenous toxicity of the contrast media. The ratio 3 contrast media produce less hypertonic solutions than the ratio 1.5 contrast media and should be preferred for angiography because they cause less pain and do not require the addition of local anesthetics which increase the acute toxicity of the solutions. (orig.)

  10. Radiographic contrast media

    International Nuclear Information System (INIS)

    Golman, K.; Holtz, E.; Almen, T.

    1987-01-01

    Contrast media are used in diagnostic radiology to enhance the X-ray attenuation between a body structure of interest and the surrounding tissue. A detail becomes perceptible on a roentgenogram only when its contrast exceeds a minimum value in relation to the background. Small areas of interest must have higher contrast than the background. The contrast effect depends on concentration of the contrast media with the body. A high contrast media concentration difference thus gives rise to more morphological details in the radiographs. Contrast media can be divided into negative contrast media such as air and gas which attenuate X-rays less than the body tissues, and positive contrast materials which attenuate X-rays more than the body tissues. The positive contrast media all contain either iodine (atomic number 53) or barium (atomic number 56) and can be divided into water-insoluble and water-soluble contrast media

  11. The diagnostic effectiveness of contrast media in the excretory urography in dogs

    International Nuclear Information System (INIS)

    Velesova, M.; Ledecky, V.

    2005-01-01

    A clinical study was conducted to investigate the use of four different positive contrast media, Omnipaque (Nycomed Imaging As.), Optiray (Maliincrodt Medical GmbH), Ultravist (Schering AG), and Urografin (Schering AG) in normograde excretory urography. Investigations were carried out on thirteen dogs. Each group of dogs was administered a different contrast medium. Radiographs were obtained immediately after the administration of contrast media and after a lapse of 5, 10 and 15 minutes. The effectiveness of the application was evaluated by assessing the radiographs of abdominal cavities in ventro-dorsal and latero-lateral positions. None of the dogs showed pronounced side effect after the application of contrast media. Ectopic ureter was diagnosed in three and a prostate cyst in one of the patients. Our results showed that Omnipaque and Ultravist were the contrast agents most suitable for the examination of the urinary apparatus by intravenous contrast excretory urography. Their advantage is that visualisation of the kidneys and ureters achieved by these media are sufficiently long and contrastive

  12. Administrating Solr

    CERN Document Server

    Mohan, Surendra

    2013-01-01

    A fast-paced, example-based guide to learning how to administrate, monitor, and optimize Apache Solr.""Administrating Solr"" is for developers and Solr administrators who have a basic knowledge of Solr and who are looking for ways to keep their Solr server healthy and well maintained. A basic working knowledge of Apache Lucene is recommended, but this is not mandatory.

  13. Administrative Synergy

    Science.gov (United States)

    Hewitt, Kimberly Kappler; Weckstein, Daniel K.

    2012-01-01

    One of the biggest obstacles to overcome in creating and sustaining an administrative professional learning community (PLC) is time. Administrators are constantly deluged by the tyranny of the urgent. It is a Herculean task to carve out time for PLCs, but it is imperative to do so. In this article, the authors describe how an administrative PLC…

  14. Contrast radiography of the lower urinary tract in the management of obstructive urolithiasis in small ruminants and swine

    International Nuclear Information System (INIS)

    Palmer, J.L.; Dykes, N.L.; Love, K.; Fubini, S.L.

    1998-01-01

    Contrast radiographic visualization of the small ruminant and porcine lower urinary tract is an infrequently used modality for the evaluation and management of obstructive urolithiasis. The administration of contrast medium through a tube cystostomy catheter used to divert urine flow until the resolution of the obstruction may provide an easy method to evaluate the status of the urethral obstruction. Contrast fluoroscopy is utilized to monitor and visualize therapeutic flushing of the urethra. A review of 26 patients seen at the Veterinary Medical Teaching Hospital suggested that among the radiographic techniques used, positive contrast normograde cystourethrography through the tube cystostomy catheter allowed the best visualization of the lower urinary tract structures and enabled assessment of the resolution of the obstructive lesion

  15. [Radiographic, MR or ultrasound contrast media in pregnant or breast-feeding women: what are the key issues?].

    Science.gov (United States)

    Fröhlich, J M; Kubik-Huch, R A

    2013-01-01

    The use and the safety of radiographic, MR- or ultrasound contrast media in the diagnostic work-up of pregnant or lactating patients is a frequently discussed question. As only sparse clinical data is available, a careful benefit-risk assessment must contain physico-chemical properties, preclinical data including teratogeneity and embryotoxicity, as well as maternal and foetal exposure. With consideration to the individual risks, iodinated contrast media, macrocyclic MR contrast media with increased stability or sulphur hexafluoride ultrasound contrast media may, if clinically justified, be administered in the smallest possible doses throughout pregnancy. After parental administration of an iodinated contrast medium after the 12th week of pregnancy, the neonate's thyroidal function should be checked during the first week after birth. After parental administration of iodinated, stable macrocyclic, gadolinium or ultrasound contrast media, lactation can be continued normally. In any case, contrast media should be used with caution and only if the benefits outweigh the risk. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Administrative Circulars

    CERN Document Server

    Département des Ressources humaines

    2004-01-01

    Administrative Circular N° 2 (Rev. 2) - May 2004 Guidelines and procedures concerning recruitment and probation period of staff members This circular has been revised. It cancels and replaces Administrative Circular N° 2 (Rev. 1) - March 2000. Administrative Circular N° 9 (Rev. 3) - May 2004 Staff members contracts This circular has been revised. It cancels and replaces Administrative Circular N° 9 (Rev. 2) - March 2000. Administrative Circular N° 26 (Rev. 4) - May 2004 Procedure governing the career evolution of staff members This circular has also been revised. It Administrative Circulars Administrative Circular N° 26 (Rev. 3) - December 2001 and brings up to date the French version (Rev. 4) published on the HR Department Web site in January 2004. Operational Circular N° 7 - May 2004 Work from home This circular has been drawn up. Operational Circular N° 8 - May 2004 Dealing with alcohol-related problems...

  17. Comparative evaluation of positive contrast and double contrast gastrography in dogs

    International Nuclear Information System (INIS)

    Dileepkumar, K.M.; Rajankutty, K.; Sarada, Amma T.; Devanand, C.B.; Vijayan, N.

    2012-01-01

    A contrast radiography of stomach with oral barium sulphate suspension 25% (5 mL/kg b.wt positive contrast) and double contrast with oral barium sulphate 25% (3 mL/kg b.wt) followed by air (2 to 10 mL/kg b.wt, negative contrast) was done on six dogs to study the affections of stomach. Contrast radiography using barium sulphate alone was found satisfactory to identify most of the lesions of the stomach. Double contrast radiography using barium sulphate and air, required sedation to control the animals for proper administration. For the diagnosis of mucosal lesions, double contrast radiography was better than barium sulphate alone. Key words: Barium, Contrast radiography, Dog, Double contrast, Stomach

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

    Science.gov (United States)

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

    2014-05-13

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

  19. Administrative Reform

    DEFF Research Database (Denmark)

    Plum, Maja

    Through the example of a Danish reform of educational plans in early childhood education, the paper critically addresses administrative educational reforms promoting accountability, visibility and documentation. Drawing on Foucaultian perspectives, the relation between knowledge and governing...... of administrative technology, tracing how the humanistic values of education embed and are embedded within ‘the professional nursery teacher' as an object and subject of administrative practice. Rather than undermining the humanistic potential of education, it is argued that the technology of accounting...

  20. The effect of timing of intravenous muscle relaxant on the quality of double-contrast barium enema

    International Nuclear Information System (INIS)

    Elson, E.M.; Elson, E.M.; Campbell, D.M.; Halligan, S.; Shaikh, I.; Davitt, S.; Bartram, C.I.

    2000-01-01

    AIM: To determine whether the timing of buscopan administration during double-contrast barium enema examination (DCBE) affects diagnostic quality. MATERIALS AND METHODS: In a prospective setting, 100 consecutive adult out-patients referred for DCBE received 20 mg buscopan (hyoscine-N-butylbromide) intravenously, either before infusion of barium suspension (Group A) or after barium infusion and gas insufflation (Group B). A subjective assessment of ease of contrast medium infusion was made at the time of examination and the films subsequently analysed by two radiologists unaware of the mode of relaxant administration, who noted the quality of mucosal coating and made subjective and objective measurements of segmental distension. RESULTS: There was no significant difference in screening times, infusion difficulty or colonic contrast medium coating between the two groups. Subjective assessment of distension of the caecum, ascending colon, transverse colon and rectum were not significantly different. Patients receiving intravenous relaxant after barium and gas infusion had less subjective descending (P = 0.05) and sigmoid (P = 0.04) colon distension, but there was no significant difference with respect to maximal bowel diameter in any of the segments measured. CONCLUSION: The timing of intravenous administration during DCBE is likely to have no significant effect on the diagnostic quality of the study. Elson, E.M. (2000)

  1. Administration in an operating plant

    International Nuclear Information System (INIS)

    Staebler, K.

    1977-01-01

    The importance of strict administrative procedures in the daily work is being demonstrated by commenting on events that occured in the operation of German nuclear power plants. The procedure for working in an area of the plant (pressurized medium, high-radioactive level, explosive of flammable mediums), where special measures for safe working have to be taken, is discussed in detail. The administrative problems during refuelling time are further on mentioned, especially the problems connected with administering more than 1,000 people with respect to health protection and sabotage protection. Some general comments on the influences from external causes (authorities, courts, etc.) are given. (orig./ORU) [de

  2. Variable effects of radiological contrast media on thrombus growth in a rabbit jugular vein thrombosis model

    NARCIS (Netherlands)

    Levi, M. [=Marcel M.; Biemond, B. J.; Sturk, A.; Hoek, J.; ten Cate, J. W.

    1991-01-01

    We studied the effect of an ionic high osmolar contrast medium (Ioxitalamate), an ionic low osmolar contrast medium (Ioxaglate) and various nonionic low osmolar contrast media (Iopamidol, Iopromide and Iohexol) on thrombus growth in a rabbit jugular vein thrombosis model. Thrombus growth was

  3. Contrast Agent in Magnetic Resonance Imaging

    DEFF Research Database (Denmark)

    Vu-Quang, Hieu

    2015-01-01

    Nanoparticles have been employed as contrast agent in magnetic resonance imaging (MRI) in order to improve sensitivity and accuracy in diagnosis. In addition, these contrast agents are potentially combined with other therapeutic compounds or near infrared bio-imaging (NIR) fluorophores to obtain...... theranostic or dual imaging purposes, respectively. There were two main types of MRI contrast agent that were synthesized during this PhD project including fluorine containing nanoparticles and magnetic nanoparticles. In regard of fluorine containing nanoparticles, there were two types contrast agent...... cancer cells for cancer diagnosis in MRI. F127-Folate coated SPION were stable in various types of suspension medium for over six months. They could specifically target folate receptor of cancer cells in vitro and in vivo thus enhancing the contrast in MRI T2/T2* weighted images. These are preliminary...

  4. Concept medium programme

    DEFF Research Database (Denmark)

    Bjerrum, Peter

    2005-01-01

    The present essay is an attempt to determine the architectural project of the 21st century in relation to a modern conception of space as the medium of architecture, and of sociality as its program......The present essay is an attempt to determine the architectural project of the 21st century in relation to a modern conception of space as the medium of architecture, and of sociality as its program...

  5. Generalized phase contrast:

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Palima, Darwin

    Generalized Phase Contrast elevates the phase contrast technique not only to improve phase imaging but also to cross over and interface with diverse and seemingly disparate fields of contemporary optics and photonics. This book presents a comprehensive introduction to the Generalized Phase Contrast...

  6. Na+/Ca2+ exchange inhibitor, KB-R7943, attenuates contrast-induced acute 
kidney injury.

    Science.gov (United States)

    Yang, Dingwei; Yang, Dingping; Jia, Ruhan; Tan, Jin

    2013-01-01

    Intracellular Ca2+ overload is considered to be a key factor in contrast-induced acute kidney injury (CI-AKI). The Na+/Ca2+ exchanger (NCX) system is one of the main pathways of intracellular Ca2+ overload. We investigated the effects of KB-R7943, an inhibitor of the reverse mode of NCX, on CI-AKI in a rat model. Rats were divided into control group, CI-AKI group and pretreatment groups (with KB-R7943 dose of 5 or 10 mg/kg). CI-AKI was induced by diatrizoate administration in rats with cholesterol-supplemented diet for 8 weeks. Renal function and renal hemodynamics were determined 1 day following contrast medium administration. Renal histopathology was observed by light microscope. Renal tubular apoptosis was examined by TUNEL. Renal endothelin-1 (ET-1) was measured by radioimmunoassay. Renal malondialdehyde (MDA) and catalase (CAT) were measured as oxidative markers. Levels of serum creatinine (Scr), renal ET-1, MDA and CAT, and resistance index (RI) of renal blood vessels increased significantly in CI-AKI rats. The 
increases in Scr and RI of renal blood vessels induced by diatrizoate were suppressed significantly and 
dose-dependently by pretreatment with KB-R7943. Histopathological and TUNEL results showed that 
the contrast medium-induced severe renal tubular 
necrosis and apoptosis were significantly and dose-dependently attenuated by KB-R7943. KB-R7943 significantly suppressed the increment of renal ET-1 content and MDA and CAT level induced by contrast medium administration. Activation of the reverse mode of NCX, followed by ET-1 overproduction and increased oxidative stress, seems to play an important role in the pathogenesis of CI-AKI. The inhibitor of the reverse mode of NCX, KB-R7943, has renoprotective effects on CI-AKI.

  7. BRAZILIAN ADMINISTRATION, ADMINISTRATIVE REFORM AND THE NEW STATE: THE ROLE OF ADMINISTRATIVE APPARATUS IN VARGAS ADMINISTRATION

    Directory of Open Access Journals (Sweden)

    Emerson Moura

    2016-07-01

    Full Text Available The role played by the administrative apparatus through the Department of Administrative Services in the Government policy Vargas is the object put in debate. Analyzes the theme from the the investigation of patrimonial, authoritarian and inefficient context which marks the formation and development of administrative bureaucracy, the tenders of professionalization and efficiency brought by the administrative reforms of the 1930s and 1940s with the contrast of the limitations of the import of the Weberian model in the Brazilian context and analysis of the establishment of the New State DASP and their assignments. Search the work demonstrate the control position he held directly and through the State Departments in the Brazilian Public Administration ensuring centralized and developmental policy of the government. For this is adopted as the research method of approach structuralism in order to identify the deconstruction of the phenomenon - of administrative reforms - in the superficial perception - the proposed impersonality and efficiency as the best way of achieving the public interest - its invariant structure - the search for the adequacy of the administrative apparatus and bureaucracy for pursuit of political ends pursued by the Government.

  8. Iohexol for contrast enhancement of bowel in pediatric abdominal CT

    International Nuclear Information System (INIS)

    Smevik, B.; Westvik, J.

    1990-01-01

    Abdominal CT scans from 160 examinations performed on pediatric patients using iohexol 2 percent as contrast medium for bowel enhancement were evaluated retrospectively. When diluted with a beverage of the child's choice, iohexol has a neutral taste and cannot be detected, and 139 out of 142 patients drank the full amount of dilute contrast offered to them. The enhancement of bowel in the area of interest was graded as good (58%), reasonable (23%), or poor (19%). The contrast medium was prepared from leftovers from our angiocardiography studies. We conclude that the use of water-soluble contrast medium in a low concentration is a safe and cost-effective way of facilitating ingesion of sufficient amounts of the medium in oncologic pediatric patients undergoing cytotoxic and/or radiation treatment. (orig.)

  9. Late adverse reactions to intravascular iodinated contrast media

    International Nuclear Information System (INIS)

    Webb, Judith A.W.; Stacul, Fulvio; Thomsen, Henrik S.; Morcos, Sameh K.

    2003-01-01

    Late adverse reactions to intravascular iodinated contrast media are defined as reactions occurring 1 h to 1 week after contrast medium injection. They have received increasing interest over the past decade, but their prevalence remains uncertain and their pathophysiology is not fully understood. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and to issue guidelines. An extensive literature search was carried out and summarized in a report. Based on the available information, simple guidelines have been drawn up. The report and guidelines were discussed at the 8th European Symposium on Urogenital Radiology in Genoa. Late adverse reactions after intravascular iodinated contrast medium include symptoms such as nausea, vomiting, headache, itching, skin rash, musculoskeletal pain, and fever. A significant proportion of these reactions is unrelated to the contrast medium; however, allergy-like skin reactions are well-documented side effects of contrast media with an incidence of approximately 2%. Late reactions appear to be commoner after non-ionic dimers. The majority of late skin reactions after contrast medium exposure are probably T-cell-mediated allergic reactions. Patients at increased risk of late skin reactions are those with a history of previous contrast medium reaction and those on interleukin-2 treatment. Most skin reactions are self-limiting and resolve within a week. Management is symptomatic and similar to the management of other drug-induced skin reactions. (orig.)

  10. Medium Range Forecast (MRF) and Nested Grid Model (NGM)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Nested Grid Model (NGM) and Medium Range Forecast (MRF) Archive is historical digital data set DSI-6140, archived at the NOAA National Centers for Environmental...

  11. Contrast Enhanced US in the Abdomen

    International Nuclear Information System (INIS)

    Chung, Yong Eun; Kim, Ki Whang

    2012-01-01

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

  12. Safety of contrast media. Focus on contrast-induced nephropathy (CIN)

    International Nuclear Information System (INIS)

    Kuwatsuru, Ryohei

    2011-01-01

    Despite advances in imaging diagnosis, contrast media still play an important role in diagnosing the existence of the disease, demonstrating the extent of disease, and determining the perfusion of the disease, which is important to make a differential diagnosis. However, the administration of contrast media may cause contrast-induced nephropathy (CIN), especially in patients with renal impairment. It is estimated that 20-30% of patients with renal impairment who received contrast media develop CIN. Though the precise cause of CIN currently remains unknown, almost all injected contrast media are excreted through the kidney and the effects of contrast media on the kidney are easily understood. As CIN is the most common cause of death due to complications after receiving contrast media, prevention of CIN is important. There are several known risk factors for CIN. Patients with renal impairment, diabetes mellitus, and dehydration are at high risk for CIN. Furthermore, a high osmolar contrast media, excessive amount of contrast media, and ionic contrast media are also risk factors for CIN. CIN can be prevented in several ways. Certain drugs seem to be useful to prevent CIN, while others are harmful. Hydration is useful to prevent CIN, although there is no widely acceptable hydration method to prevent CIN. Both sodium bicarbonate and N-acetylcysteine are promising candidates for prevention of CIN. There are few reports to study CIN after intravenous administration, although reports of CIN after percutaneous cardiac intervention (PCI) and angiography are well recognized. In clinical situations, intravenous administration of contrast media is common. Therefore, a study of CIN after intravenous administration of contrast media should be performed. (author)

  13. Contrast-enhanced near-infrared laser mammography with a prototype breast scanner: feasibility study with tissue phantoms and preliminary results of imaging experimental tumors.

    Science.gov (United States)

    Boehm, T; Hochmuth, A; Malich, A; Reichenbach, J R; Fleck, M; Kaiser, W A

    2001-10-01

    Near-infrared (NIR) optical mammography without contrast has a low specificity. The application of optical contrast medium may improve the performance. The concentration-dependent detectability of a new NIR contrast medium was determined with a prototype optical breast scanner. In vivo imaging of experimental tumors was performed. The NIR contrast agent NIR96010 is a newly synthesized, hydrophilic contrast agent for NIR mammography. A concentration-dependent contrast resolution was determined for tissue phantoms consisting of whole milk powder and gelatin. A central part of the phantoms measuring 2 x 2 cm2 without contrast was replaced with phantom material containing 1 micromol/L to 25 nmol/L NIR96010. The composite phantoms were measured with a prototype NIR breast scanner with lasers of lambda1 = 785 nm and lambda2 = 850 nm wavelength. Intensity profiles and standard deviations of the transmission signal in areas with and without contrast were determined by linear fit procedures. Signal-to-noise ratios and spatial resolution as a function of contrast concentration were determined. Near-infrared imaging of five tumor-bearing SCID mice (MX1 breast adenocarcinoma, tumor diameter 5-10 mm) was performed before and after intravenous application of 2 micromol/kg NIR96010. Spectrometry showed an absorption maximum of the contrast agent at 755 nm. No spectral shifts occurred in protein-containing solution. Signal-to-noise ratio in the transmission intensity profiles ranged from 1.1 at 25 nmol/L contrast to 28 at 1 micromol/L. At concentrations contrast-enhanced images, with better delineation after contrast administration. In postcontrast absorption profiles, a 44.1% +/- 11.3% greater absorption increase was seen in tumor tissue compared with normal tissue. The laser wavelength lambda1 of the prototype laser mammography device was not situated at maximum absorption of the contrast agent NIR96010 but on the descending shoulder of the absorption spectrum. This implies a 20

  14. Iodinated contrast media nephrotoxicity. Nephrotoxicite des produits de contraste iodes

    Energy Technology Data Exchange (ETDEWEB)

    Meyrier, A. (Hopital Avicenne, 93 - Bobigny (France))

    1994-01-01

    In the late seventies, iodinated contrast agents (ICA) were considered to be a major cause of acute iatrogenic renal failure. Over the last decade new contrast agents have been synthesized, nonionic and less hyperosmolar. The incidence of acute renal failure due to ICAs, varies from 3.7 to 70% of cases according to the series, with an average figure of 10.2%. The pathophysiology of ICA nephrotoxicity was mainly studied in laboratory animal models. Three main factors are involved in an inducing ICA-mediated decrease in glomerular filtration rate: reduction of the renal plasma flow, a direct cytotoxic effect on renal tubular cells and erythrocyte alteration leading to intra-renal sludge. Excluding dysglobulinemias with urinary excretion of immunoglobulin light chains, which represent a special case of maximum nephrotoxicity, 4 main risk factors of renal toxicity have been identified in nondiabetic subjects: previous renal failure with serum creatinine levels greater than 140 [mu]mol per liter, extracellular dehydration, age over 60 and use of high doses of ICA and/or repeated ICA injections before serum creatinine levels return to baseline. Preventive measures for avoiding ICA nephrotoxicity are threefold: maintain or restore adequate hydration with saline infusion, stop NSAID treatment several days before ICA administration, and allow a 5 day interval before repeating contrast media injections. New, nonionic and moderately hyperosmolar contrast agents appear to be much less nephrotoxic than conventional ICAs in laboratory animals and in high-risk patients. It is advisable to select such contrast media for investigating high-risk patients. This approach was recently substantiated in well designed, randomized clinical studies which included more than 2 000 patients. (author).

  15. Offentlig administration

    DEFF Research Database (Denmark)

    Nielsen, Elof Nellemann; Rehr, Preben René

    En undervisningsbog der henvender sig til administrationsbacheloruddannelsen. Kapitlerne er inddelt efter modulerne på uddannelsen og indeholder derfor elementer af administration, forvaltning, økonomistyring, innovation, samfundsvidenskabelige metoder og politisk styrede organisationer.......En undervisningsbog der henvender sig til administrationsbacheloruddannelsen. Kapitlerne er inddelt efter modulerne på uddannelsen og indeholder derfor elementer af administration, forvaltning, økonomistyring, innovation, samfundsvidenskabelige metoder og politisk styrede organisationer....

  16. SAT administrator

    International Nuclear Information System (INIS)

    Havas, A.

    1998-01-01

    SAT Administrator is the Information System for Nuclear Power Plant Personnel Training Program Design. It supports the design of training programs in the following phases: job analysis; task analysis; competency analysis; task competency association; definition of learning objectives to competencies; training program design; definition of test items. The general structure of the database and management software supports application of the SAT Administrator in any nuclear power installation

  17. The Interstellar Medium

    CERN Document Server

    Lequeux, James

    2005-01-01

    Describing interstellar matter in our galaxy in all of its various forms, this book also considers the physical and chemical processes that are occurring within this matter. The first seven chapters present the various components making up the interstellar matter and detail the ways that we are able to study them. The following seven chapters are devoted to the physical, chemical and dynamical processes that control the behaviour of interstellar matter. These include the instabilities and cloud collapse processes that lead to the formation of stars. The last chapter summarizes the transformations that can occur between the different phases of the interstellar medium. Emphasizing methods over results, "The Interstellar Medium" is written for graduate students, for young astronomers, and also for any researchers who have developed an interest in the interstellar medium.

  18. Optical recording medium

    International Nuclear Information System (INIS)

    Andriech, A.; Bivol, V.; Tridukh, G.; Tsiuleanu, D.

    2002-01-01

    The invention relates of the micro- and optoelectronics, computer engineering ,in particular, to tjhe optical information media and may be used in hilography. Summary of the invention consists in that the optical image recording medium, containing a dielectric substrates, onto one surface of which there are placed in series a transparent electricity conducting layer, a photo sensitive recording layer of chalcogenic glass and a thin film electrode of aluminium, is provided with an optically transparent protective layer, applied into the thin film electrode. The result of the invention consists in excluding the dependence of chemical processes course into the medium upon environmental conditions

  19. Phase contrast image synthesis

    DEFF Research Database (Denmark)

    Glückstad, J.

    1996-01-01

    A new method is presented for synthesizing arbitrary intensity patterns based on phase contrast imaging. The concept is grounded on an extension of the Zernike phase contrast method into the domain of full range [0; 2 pi] phase modulation. By controlling the average value of the input phase funct...... function and by choosing appropriate phase retardation at the phase contrast filter, a pure phase to intensity imaging is accomplished. The method presented is also directly applicable in dark field image synthesis....

  20. Positive contrast shoulder arthrography in dogs with uropolin

    International Nuclear Information System (INIS)

    Goranov, N.; Philipov, J.; Stamoulis, Y.

    2002-01-01

    Positive contrast radiography of both shoulder joints with different concentrations of Uropolin (containing 1.6 g sodium amidotrizoate and 10.4 g meglumine amidotrizoate in 20 ml ampules; Polfa, Poland) has been performed in six dogs, divided into 3 groups. The first group was injected with 20% Uropolin, the second - with 30% Uropolin and the third - with 30% Uropolin and 0.2 ml 0.1% adrenaline hydrochloride. Shoulder radiographs were performed 2, 5 and 10 min after the injection of the contrast medium in mediolateral and craniocaudal views. The quality of radiographs was assessed visually using a four score system for five independent parameters in both views. The results showed a better quality of mediolateral radiographs 5 minutes after injection of 30% Uropolin (average score 12.5) compared to 20% Uropolin (average score 8.5), at p<0.05. The addition of 0.1% adrenaline hydrochloride to 30% Uropolin resulted in a better quality of arthrographs up to 10 minutes following the administration (average score 10 compared to 8.5 in the group with independent application, p<0.01)

  1. Radon in geological medium

    Energy Technology Data Exchange (ETDEWEB)

    Hricko, J [GEOCOMPLEX, a.s., Bratislava (Slovakia)

    1996-12-31

    The paper presented deals with behavior of the radon in geological medium and with some results of the radon survey in Bratislava and Kosice regions. 1) The a{sub v} has been detected in the holes 0.80 m deep. The density of observations - 3 reference areas (one represents 20 stations) per 1 km{sup 2}. The radon risk maps in 1:25000 and 1:50000 scales have been compiled. The 56.8% of the project area lies in low radon risk, 37.6% in medium radon risk and 5.6% in high radon risk. Follow-up monitoring of the equivalent volume radon activity (EVRA) at the flats, located in the areas with high radon risk of the surface layer, has showed values several times higher than Slovak limits (Marianka, Raca, Vajnory). The evidence that neotectonic is excellent medium for rising up emanation to the subsurface layer, is shown on the map. The tectonic zone of Liscie udolie in Bratislava-Karlova Ves area has been clearly detected by profile radon survey (a{sub v} > 50 kBq/m{sup 3}). 2) At present, northern half of the area of Kosice in question was covered by radon survey. The low and medium radon risks have been observed here, while localities with high radon risk are small in extent. The part of radon risk and soil permeability map from northern Kosice area is shown. (J.K.) 3 figs., 2 refs.

  2. Radon in geological medium

    International Nuclear Information System (INIS)

    Hricko, J.

    1995-01-01

    The paper presented deals with behavior of the radon in geological medium and with some results of the radon survey in Bratislava and Kosice regions. 1) The a v has been detected in the holes 0.80 m deep. The density of observations - 3 reference areas (one represents 20 stations) per 1 km 2 . The radon risk maps in 1:25000 and 1:50000 scales have been compiled. The 56.8% of the project area lies in low radon risk, 37.6% in medium radon risk and 5.6% in high radon risk. Follow-up monitoring of the equivalent volume radon activity (EVRA) at the flats, located in the areas with high radon risk of the surface layer, has showed values several times higher than Slovak limits (Marianka, Raca, Vajnory). The evidence that neotectonic is excellent medium for rising up emanation to the subsurface layer, is shown on the map. The tectonic zone of Liscie udolie in Bratislava-Karlova Ves area has been clearly detected by profile radon survey (a v > 50 kBq/m 3 ). 2) At present, northern half of the area of Kosice in question was covered by radon survey. The low and medium radon risks have been observed here, while localities with high radon risk are small in extent. The part of radon risk and soil permeability map from northern Kosice area is shown. (J.K.) 3 figs., 2 refs

  3. Automatic Time Sequence Alignment in Contrast Enhanced MRI by Maximization of Mutual Information

    National Research Council Canada - National Science Library

    Positano, Vicenzo

    2001-01-01

    The use of contrast medium allows joining the high-resolution anatomical information provided by standard magnetic resonance with functional information obtained by means of the diffusion of contrast...

  4. Dense Medium Plasma Water Purification Reactor (DMP WaPR), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Dense Medium Plasma Water Purification Reactor offers significant improvements over existing water purification technologies used in Advanced Life Support...

  5. Contrast-enhanced dynamic MR imaging of parasellar tumor using fast spin-echo sequence

    International Nuclear Information System (INIS)

    Kusunoki, Katsusuke; Ohue, Shiro; Ichikawa, Haruhisa; Saito, Masahiro; Sadamoto, Kazuhiko; Sakaki, Saburo; Miki, Hitoshi.

    1995-01-01

    We have applied a new dynamic MRI technique that uses a fast spin-echo sequence to parasellar tumors. This sequence has less susceptible effect and better spatial resolution than a gradient echo sequence, providing faster images than a short spin-echo sequence does. Image was obtained in the coronal or sagittal plane using a 1.5T clinical MRI system, and then, dynamic MR images were acquired every 10 to 20 sec after administration of Gd-DTPA (0.1 mmol/kg). The subjects were 12 patients (5 microadenomas, 5 macroadenomas and 2 Rathke's cleft cysts) and 5 normal volunteers. As for volunteers, the cavernous sinus, pituitary stalk and posterior pituitary gland were contrasted on the first image, followed by visualization of the proximal portion adjacent to the junction of the infundibulum and the anterior pituitary gland, and finally by contrasting the distal portion of the anterior pituitary gland. There was a difference with respect to tumor contrast between microadenomas and macroadenomas. In the case of the macroadenomas, the tumor was contrasted at the same time as, or faster than the anterior pituitary gland, while with the microadenomas the tumor was enhanced later than the anterior pituitary gland. No enhancement with contrast medium was seen in Rathke's cleft cysts. In addition, it was possible to differentiate a recurrent tumor from a piece of muscle placed at surgery since the images obtained by the fast spin-echo sequence were clearer than those obtained by gradient echo sequence. (author)

  6. Late adverse reactions to intravascular iodine based contrast media

    DEFF Research Database (Denmark)

    Bellin, Marie-France; Stacul, Fulvio; Webb, Judith A W

    2011-01-01

    DEFINITION: Late adverse reactions (LAR) to contrast media (CM) are defined as reactions occurring 1 h to 1 week after exposure. NEED FOR REVIEW: In view of more prospective studies of LAR and new data about their pathophysiology, the Contrast Medium Safety Committee (CMSC) of the European Societ...

  7. Contrast analysis : A tutorial

    NARCIS (Netherlands)

    Haans, A.

    2018-01-01

    Contrast analysis is a relatively simple but effective statistical method for testing theoretical predictions about differences between group means against the empirical data. Despite its advantages, contrast analysis is hardly used to date, perhaps because it is not implemented in a convenient

  8. Process for preparation of MR contrast agents

    DEFF Research Database (Denmark)

    2002-01-01

    The present invention provides a process for the preparation of an MR contrast agent, said process comprising: i) obtaining a solution in a solvent of a hydrogenatable, unsaturated substrate compound and a catalyst for the hydrogenation of said substrate compound; ii) introducing said solution...... in droplet form into a chamber containing hydrogen gas (H2) enriched in para-hydrogen (p-1H2) and/or ortho-deuterium (o-2H2) whereby to hydrogenate said substrate to form a hydrogenated imaging agent; iii) optionally subjecting said hydrogenated imaging agent to a magnetic field having a field strength below...... earth's ambient field strength; iv) optionally dissolving said imaging agent in an aqueous medium; v) optionally separating said catalyst from the solution of said imaging agent in said aqueous medium; vi) optionally separating said solvent from the solution of said imaging agent in said aqueous medium...

  9. Administrative circular

    CERN Multimedia

    2003-01-01

    • N° 21 - August 2003 Special leave This circular has been amended. Copies of this circular are available in the Divisional Secretariats. In addition, administrative and operational circulars, as well as the lists of those in force, are available for consultation on the Web at: http://cern.ch/hr-div/internal/admin_services/admincirc/listadmincirc.asp Human Resources Division Tel. 74128

  10. Database Administrator

    Science.gov (United States)

    Moore, Pam

    2010-01-01

    The Internet and electronic commerce (e-commerce) generate lots of data. Data must be stored, organized, and managed. Database administrators, or DBAs, work with database software to find ways to do this. They identify user needs, set up computer databases, and test systems. They ensure that systems perform as they should and add people to the…

  11. Administrative IT

    Science.gov (United States)

    Grayson, Katherine, Ed.

    2006-01-01

    When it comes to Administrative IT solutions and processes, best practices range across the spectrum. Enterprise resource planning (ERP), student information systems (SIS), and tech support are prominent and continuing areas of focus. But widespread change can also be accomplished via the implementation of campuswide document imaging and sharing,…

  12. MR mammography: influence of menstrual cycle on the dynamic contrast enhancement of fibrocystic disease

    International Nuclear Information System (INIS)

    Rieber, A.; Nuessle, K.; Merkle, E.; Tomczak, R.; Brambs, H.J.; Kreienberg, R.

    1999-01-01

    Magnetic resonance mammography (MRM) provides data regarding the nature of tumours based on contrast medium dynamics; fibrocystic changes in the breast, however, may lead to false-positive results. This study investigated whether the contrast medium dynamics of fibrocystic changes are dependent on the menstrual cycle. Twenty-four patients with palpable lumps but normal mammographies and ultrasound studies were examined. The MRM technique was performed during the first and second part of the menstrual cycle using a FLASH 3D sequence, both native and at 1, 2, 3 and 8 min after intravenous application of 0.15 mmol/kg body weight of gadodiamide. The calculated time-intensity curves were evaluated based on the following criteria: early percentage of contrast medium uptake in relation to the native value; formation of a plateau phenomenon after the second minute; the point of maximal contrast medium uptake; and calculation of the contrast enhancing index. During the second half of the menstrual cycle, a generally greater contrast medium uptake was observed. Nevertheless, when further diagnostic criteria, such as continuous contrast medium increase as a function of time, were considered, there was no increased rate of false-positive findings. The phase of the menstrual cycle may affect the specificity of the examination, if only the quantitative contrast medium uptake and the percentage of contrast medium uptake in the first 2 min are considered. A control MRM during the other half of the cycle may then be indicated and additional diagnostic criteria may improve specificity. (orig.)

  13. Prolonged retainment of contrast media in renal tumours by oily X-ray contrast media

    International Nuclear Information System (INIS)

    Ryzkov, V.K.; Anisimov, V.N.

    1990-01-01

    In 194 patients with renal tumours an angiographic investigation with the oily X-ray contrast medium Iodolipol was carried out. A selective tropism of oily X-ray contrast media was found in the malignant zones only. The application of the preparation caused no complications. The oily X-ray contrast medium persisted in the tumours over several weeks or months. After embolization of the renal arteria a moderate size reduction of malign tumours in the first 10-14 d was seen. The ability of Iodolipol for a lasting retainment in malign tumour tissue allows a follow-up of the involution of the pathologic focus after arterial embolization of the tumour vessels. (author)

  14. Contrast media in urography, angiography and computerized tomography

    International Nuclear Information System (INIS)

    Taenzer, V.; Zeitler, E.

    1983-01-01

    The fact that new contrast media have been introduced in Germany or are currently undergoing clinical trials prompted the authors to assemble available experiences in a special edition of ''Roentgen-Fortschritte''. Particular prominence is given in the publication to preclinical and clinical experiences with another new non-ionic contrast medium, Iopromide. Experimental and clinical studies both indicate changes in certain clinically pertinent properties of the new contrast media. (orig./MG) [de

  15. Contrast enhancement of the gyri in herpes simplex encephalitis

    International Nuclear Information System (INIS)

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

    1982-01-01

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

  16. Contrast agents for MRI

    International Nuclear Information System (INIS)

    Bonnemain, B.

    1994-01-01

    Contrast agents MRI (Magnetic Resonance Imaging) have been developed to improve the diagnostic information obtained by this technic. They mainly interact on T1 and T2 parameters and increase consequently normal to abnormal tissues contrast. The paramagnetic agents which mainly act on longitudinal relaxation rate (T1) are gadolinium complexes for which stability is the main parameter to avoid any release of free gadolinium. The superparamagnetic agents that decrease signal intensity by an effect on transversal relaxation rate (T2) are developed for liver, digestive and lymph node imaging. Many area of research are now opened for optimal use of present and future contrast agents in MRI. (author). 28 refs., 4 tabs

  17. Compressive Phase Contrast Tomography

    International Nuclear Information System (INIS)

    Maia, Filipe; MacDowell, Alastair; Marchesini, Stefano; Padmore, Howard A.; Parkinson, Dula Y.; Pien, Jack; Schirotzek, Andre; Yang, Chao

    2010-01-01

    When x-rays penetrate soft matter, their phase changes more rapidly than their amplitude. Interference effects visible with high brightness sources creates higher contrast, edge enhanced images. When the object is piecewise smooth (made of big blocks of a few components), such higher contrast datasets have a sparse solution. We apply basis pursuit solvers to improve SNR, remove ring artifacts, reduce the number of views and radiation dose from phase contrast datasets collected at the Hard X-Ray Micro Tomography Beamline at the Advanced Light Source. We report a GPU code for the most computationally intensive task, the gridding and inverse gridding algorithm (non uniform sampled Fourier transform).

  18. Concept medium program

    DEFF Research Database (Denmark)

    Bjerrum, Peter

    2003-01-01

    The present essays is an attempt to dertermine the architecural project of the 21st century in realation to a modern conception of space as the medium of architecture, and of society as its program. This attempt adopts the internal point of view of an architect in describing a modern architectural...... project within the framework: concept - program, these notions being concieved as spatial representations primarily and immediately "given" to architecture....

  19. Contrast media in computed tomography of the pelvic organs

    International Nuclear Information System (INIS)

    Husband, J.E.

    1981-01-01

    The use of various contrast media is essential for examination of the pelvis with computed tomography (CT) because there is little fat between the organs and structures and because bowel may be misinterpreted as mass. Routine opacification of the distal small bowel and colon is achieved using dilute oral and rectal contrast medium, and all patients are scanned with a full bladder. A tampon is used to outline the vaginal vault. Intravenous contrast medium may be required to opacify the urinary tract or to distinguish vessels from a suspected space-occupying lesion. Pelvic masses may show tissue enhancement following injection of intravenous contrast medium but further studies are required to determine the diagnostic value of the information obtained. (Auth.)

  20. Generalized Phase Contrast

    CERN Document Server

    Glückstad, Jesper

    2009-01-01

    Generalized Phase Contrast elevates the phase contrast technique not only to improve phase imaging but also to cross over and interface with diverse and seemingly disparate fields of contemporary optics and photonics. This book presents a comprehensive introduction to the Generalized Phase Contrast (GPC) method including an overview of the range of current and potential applications of GPC in wavefront sensing and phase imaging, structured laser illumination and image projection, optical trapping and manipulation, and optical encryption and decryption. The GPC method goes further than the restrictive assumptions of conventional Zernike phase contrast analysis and achieves an expanded range of validity beyond weak phase perturbations. The generalized analysis yields design criteria for tuning experimental parameters to achieve optimal performance in terms of accuracy, fidelity and light efficiency. Optimization can address practical issues, such as finding an optimal spatial filter for the chosen application, ...

  1. Mamografia Espectral de Contraste

    OpenAIRE

    Martins, Inês Santiago; Pereira, Inês; Pacheco, Hugo Pisco; Moutinho, Leonor

    2014-01-01

    A mamografia de contraste é uma aplicação recente possível com a mamografia digital directa, que utiliza contraste iodado endovenoso tendo como princípio a neovascularização induzida no cancro da mama, permitindo obter informação morfológica e funcional. Na mamografia espectral de contraste realiza-se uma aquisição simultânea com alta e baixa energia para cada incidência após administração de contraste iodado endovenoso. É depois feita uma imagem recombinada em que são realçadas as áreas que ...

  2. Ionic and non-ionic contrast media used for contrast-enhanced computed tomography in experimental pancreatitis

    International Nuclear Information System (INIS)

    Kivisaari, L.; Nuutinen, P.; Lehtola, A.; Saari, A.; Pitkaeranta, P.; Standertskjoeld-Nordenstam, C.G.; Lempinen, M.; Schroeder, T.; Helsinki Univ. Central Hospital

    1988-01-01

    Contrast enhancement of the pancreas was studied in pigs using dynamic computed tomography in experimental oedematous and haemorrhagic/necrotizing pancreatitis during the first two minutes after injection of an intravenous bolus of non-ionic contrast medium (iohexol). The prospects of separating the two forms of the disease, known to be possible with ionic contrast media, were tested with a non-ionic contrast medium. In the oedematous form, contrast enhancement after 5 hours of the disease was significantly higher than in the haemorrhagic/necrotizing form. Contrast enhancement after 30 hours of disease tended to vary with the severity of the disease, showing that the course of oedematous pancreatitis is dynamic. Intermediate forms occur and follow-up studies are needed during the disease. A non-ionic contrast medium proved as good for separating the two forms of the disease in the early phase as were ionic contrast media. In severely ill patients, non-ionic contrast media should therefore be used. (orig.)

  3. A survey of contrast media used in coronary angiograph

    International Nuclear Information System (INIS)

    Weikl, A.; Hubmann, M.

    1982-01-01

    In recent years, various contrast media have been developed for use in coronary angiography. These contrast media may be divided into ionic contrast media of high osmolality, those of low osmolality, and nonionic contrast materials. We conducted our own clinical studies with 40 patients. In random succession a standard contrast medium (ionic, of high osmolality) and a new-generation contrast medium (either nonionic or ionic with low osmolality) were injected into the right and left coronary arteries. After each injection we measured the systolic and diastolic blood pressure using a liquid-filled coronary catheter. In addition, the change in the length of the cardiac cycle was registered in terms of the R-R interval (in ms) and at the same time, leads I, II, and III of the ECG were recorded. We studied the influence of the various contrast media on the activity of ATPase in in vitro experiments, using Lasser and Lang's. When ionic contrast media of low osmolality and nonionic contrast media were utilized the heart rate showed no change. Disturbances of rhythm such as ventricular tachycardia or fibrillation were not observed. All of the contrast media used produced the same ECG changes. These changes can be ascribed to the inhibition of ATPase. The arterial blood pressure was lowered significantly only by ionic contrast media of high osmolality only. (orig.)

  4. Comparison of contrast media for visualization of the colon of healthy dogs during computed tomography and ultrasonography.

    Science.gov (United States)

    Cheon, Byunggyu; Moon, Sohyeon; Park, Seungjo; Lee, Sang-Kwon; Hong, Sunghwa; Cho, Hyun; Choi, Jihye

    2016-11-01

    OBJECTIVE To evaluate contrast agents for their ability to improve visualization of the colon wall and lumen during CT and ultrasonography. ANIMALS 10 healthy adult Beagles. PROCEDURES Food was withheld from dogs for 36 hours, after which dogs consumed 250 mL of polyethylene glycol solution. Dogs were then anesthetized, a contrast agent (tap water, diluted barium, or air; order randomly assigned) was administered rectally, iodine contrast medium (880 mg of I/kg) was administered IV, and CT and ultrasonography of the colon were performed. After a 1-week washout period, this process was repeated with a different contrast agent until all agents had been evaluated. Two investigators reviewed the CT and ultrasonographic images for colon wall thickness, conspicuity, artifacts, wall layering, and degree of lumen dilation at 4 sites. RESULTS Thickness of the colon wall was greatest in CT and ultrasonographic images with water used as contrast agent, followed by barium and then air. The CT images obtained after water administration had a smooth appearance that outlined the colonic mucosa and had the highest score of the 3 contrast agents for wall conspicuity. Although no substantial artifacts related to any of the contrast agents were identified on CT images, barium- and gas-induced shadowing and reverberation artifacts hindered wall evaluation during ultrasonography. For ultrasonography, the degree of conspicuity was highest with barium in the near-field wall and with water in the far-field wall. In contrast to CT, ultrasonography could be used to distinguish wall layering, and the mucosal and muscular layers were distinct with all contrast agents. CONCLUSIONS AND CLINICAL RELEVANCE Use of water as a contrast agent for both CT and ultrasonography of the colon in dogs compensated for each imaging modality's disadvantages and could be beneficial in the diagnosis of colon disease.

  5. Consideration of Adverse Reaction to MDCT Contrast Media

    International Nuclear Information System (INIS)

    Yang, Won Seok; Shin, Seong Gyu

    2012-01-01

    In this experiment, we investigated 82 patients who suffered adverse reactions due to contrast medium. We selected the subjects out of 21,178 people who had an intravenous injection of contrast medium to undergo MDCT examination at one university hospital in Busan in 2007. As a result, the largest groups of the patients were as follows. 52.4% of the patients were male when classify by gender; 28.0% of the patients were 50's by age; 45% of the patients got when it was spring(April and March); 75.6% of the patients had a side effects when the speed of injection is 2.5 mL/sec; 58.5% of the patients were suffered when the volume of injected contrast medium is over 130 mL. Urticaria was the main symptom of side effect as 26.8%. And the main treatment for the effect was alleviating the symptoms before making patients to return home. Thus, practical preventive measures are needed as follows: use the OCS system to observe warning signs at risky patients, secure warming spaces for patients to cope with season changing, prepare enough emergency kits for the patients in danger, and establish CPR call systems, explain the risk of contrast medium and get agree about using contrast medium.

  6. Effects of age and brightness contrast on perception of the Wundt-Hering illusion.

    Science.gov (United States)

    Astor-Stetson, E; Purnell, T G

    1990-10-01

    Susceptibility to the Wundt-Hering illusion was studied as a function of age and contrast. Preschoolers, third-graders and college students were shown light-grey, medium-grey, and black Wundt-Hering figures on white ground. Pre-schoolers were most susceptible to the illusion, differing from third graders in the medium and high contrast conditions and from college students in all contrast conditions. Low contrast figures resulted in significantly less distortion than did high contrast figures for the preschoolers. The significant interaction of age and contrast effects highlights the importance of a developmental approach to the study of illusions.

  7. Administrative contracts

    Directory of Open Access Journals (Sweden)

    Vukićević-Petković Milica

    2015-01-01

    Full Text Available Administrative contracts are a special type of contract where usually one of the contracting parties is a public law body and which is concluded for the performance of public service and the realization of a public interest. They go a long way since its inception to its eventual final acceptance of all the legal systems. One of the enduring characteristics of this type of contract is their disquised or unnoticed existence. This is why only monitoring their development may lead to a complete understanding of the importance and essence of this institution as well as the need for its complete legal regulation.

  8. Administrative contracts

    OpenAIRE

    Vukićević-Petković Milica

    2015-01-01

    Administrative contracts are a special type of contract where usually one of the contracting parties is a public law body and which is concluded for the performance of public service and the realization of a public interest. They go a long way since its inception to its eventual final acceptance of all the legal systems. One of the enduring characteristics of this type of contract is their disquised or unnoticed existence. This is why only monitoring their development may lead to a complete u...

  9. Safe use of iodinated and gadolinium-based contrast media in current practice in Japan: a questionnaire survey.

    Science.gov (United States)

    Tsushima, Yoshito; Ishiguchi, Tsuneo; Murakami, Takamichi; Hayashi, Hiromitsu; Hayakawa, Katsumi; Fukuda, Kunihiko; Korogi, Yukunori; Sugimoto, Hideharu; Takehara, Yasuo; Narumi, Yoshifumi; Arai, Yasuaki; Kuwatsuru, Ryohei; Yoshimitsu, Kengo; Awai, Kazuo; Kanematsu, Masayuki; Takagi, Ryo

    2016-02-01

    To help establish consensus on the safe use of contrast media in Japan. Questionnaires were sent to accredited teaching hospitals with radiology residency programs. The reply rate was 45.4% (329/724). For contrast-induced nephropathy (CIN), chronic and acute kidney diseases were considered a risk factor in 96.7 and 93.6%, respectively, and dehydration in 73.9%. As preventive actions, intravenous hydration (89.1%) and reduction of iodinated contrast media dose (86.9%) were commonly performed. For nephrogenic systemic fibrosis (NSF), chronic and acute kidney diseases were considered risk factors in 98.5 and 90.6%, respectively, but use of unstable gadolinium-based contrast media was considered a risk factor in only 55.6%. A renal function test was always (63.5% in iodinated; 65.7% in gadolinium) or almost always (23.1; 19.8%) performed, and estimated glomerular filtration rate (eGFR) was the parameter most frequently used (80.8; 82.6%). For the patients with risk factors for acute adverse reaction (AAR), steroid premedication or/and change of contrast medium were frequent preventive actions, but intravenous steroid administration immediately before contrast media use was still performed. Our questionnaire survey revealed that preventive actions against CIN were properly performed based on patients' eGFR. Preventive actions against NSF and AAR still lacked consensus.

  10. DENSE MEDIUM CYCLONE OPTIMIZATON

    Energy Technology Data Exchange (ETDEWEB)

    Gerald H. Luttrell; Chris J. Barbee; Peter J. Bethell; Chris J. Wood

    2005-06-30

    Dense medium cyclones (DMCs) are known to be efficient, high-tonnage devices suitable for upgrading particles in the 50 to 0.5 mm size range. This versatile separator, which uses centrifugal forces to enhance the separation of fine particles that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash and lead-zinc ores. Due to the high tonnage, a small increase in DMC efficiency can have a large impact on plant profitability. Unfortunately, the knowledge base required to properly design and operate DMCs has been seriously eroded during the past several decades. In an attempt to correct this problem, a set of engineering tools have been developed to allow producers to improve the efficiency of their DMC circuits. These tools include (1) low-cost density tracers that can be used by plant operators to rapidly assess DMC performance, (2) mathematical process models that can be used to predict the influence of changes in operating and design variables on DMC performance, and (3) an expert advisor system that provides plant operators with a user-friendly interface for evaluating, optimizing and trouble-shooting DMC circuits. The field data required to develop these tools was collected by conducting detailed sampling and evaluation programs at several industrial plant sites. These data were used to demonstrate the technical, economic and environmental benefits that can be realized through the application of these engineering tools.

  11. Use of high concentration contrast media: principles and rationale--vascular district

    International Nuclear Information System (INIS)

    Fleischmann, Dominik.

    2003-01-01

    Optimal contrast medium delivery remains a crucial issue in CT angiography and it will become even more critical with continuously evolving, faster CT scanner technology. This review article first explains the fundamentals of arterial enhancement using mathematical models of early contrast medium dynamics. The relationship of contrast medium volume, injection flow rates and injection duration are explicitly illustrated. Next, current techniques of contrast medium application are reviewed, with particular attention to methods of accurate timing of the scanning delay (test-bolus and automated bolus triggering), tools for automated saline-flushing of the veins (double-syringe power injectors) and the use of high-concentration contrast medium. From there, rational CT angiographic injection protocols for a wide range of selectable acquisition times for 4-, 8- and 16-channel MDCT are proposed

  12. Contrast induced nephropathy in patients undergoing intravenous (IV) contrast enhanced computed tomography (CECT) and the relationship with risk factors: a meta-analysis

    NARCIS (Netherlands)

    Moos, Shira I.; van Vemde, David N. H.; Stoker, Jaap; Bipat, Shandra

    2013-01-01

    To summarize the incidence of contrast-induced nephropathy (CIN) and associations between CIN incidence and risk factors in patients undergoing intravenous contrast-enhanced computed tomography (CECT) with low- or iso-osmolar iodinated contrast medium. This review is performed in accordance with the

  13. Contrast media: future aspects

    International Nuclear Information System (INIS)

    Weinmann, H.J.; Platzek, J.; Schirmer, H.; Pietsch, H.; Carretero, J.; Harto, J.; Medina, J.; Riefke, B.; Martin, J.

    2005-01-01

    In spite of the dramatic development in CT, there was no major breakthrough in the iodinated contrast media development. New agents based on hybrid between MRI and CT compounds may be a new innovative alternative. This new approach may also open new indications such as radiotherapy. (orig.)

  14. ADMINISTRATIVE CIRCULARS

    CERN Multimedia

    Division des ressources humaines

    2000-01-01

    N° 2 (Rev. 1) - March 2000Guidelines and procedures concerning recruitment and probation period of staff membersN° 9 (Rev. 2) - March 2000Staff members contractsN° 16 (Rev. 2) - January 2000TrainingN° 30 (Rev. 1) - January 2000Indemnities and reimbursements upon taking up appointment and termination of contractN° 32 - February 2000Principles and procedures governing complaints of harassmentThese circular have been amended (No 2, N° 9, N° 16 and N° 30) or drawn up (N° 32).Copies are available in the Divisional Secretariats.Note:\tAdministrative and operational circulars, as well as the lists of those in force, are available for consultation in the server SRV4_Home in the Appletalk zone NOVELL (as GUEST or using your Novell username and password), volume PE Division Data Disk.The Word files are available in the folder COM, folder Public, folder ADM.CIRC.docHuman Resources DivisionTel. 74128

  15. Computation as Medium

    DEFF Research Database (Denmark)

    Jochum, Elizabeth Ann; Putnam, Lance

    2017-01-01

    Artists increasingly utilize computational tools to generate art works. Computational approaches to art making open up new ways of thinking about agency in interactive art because they invite participation and allow for unpredictable outcomes. Computational art is closely linked...... to the participatory turn in visual art, wherein spectators physically participate in visual art works. Unlike purely physical methods of interaction, computer assisted interactivity affords artists and spectators more nuanced control of artistic outcomes. Interactive art brings together human bodies, computer code......, and nonliving objects to create emergent art works. Computation is more than just a tool for artists, it is a medium for investigating new aesthetic possibilities for choreography and composition. We illustrate this potential through two artistic projects: an improvisational dance performance between a human...

  16. Spiegel. Medium. Kunst

    DEFF Research Database (Denmark)

    Kacunko, Slavko

    of this kind as the marks of a meta-complex of method out of which new models of the image continually arise. The waxing intangibility of proliferating images be they of the mind, in dreams, through gestures, and the equally rampant growth of microstructuring in allocations of knowledge lay a challenge before...... to research. As a void in the apprehension of the world, the mirror obtained a scholarly perspective and the more so in areas beyond its own qualities as a medium, i.e. in images and metaphor, the paradigms of all research looking to image and text. This investigation sets out to comprehend paradoxes......, and space (albeit no expanse) is there to consider the methodological pros and cons of such a selective approach. Even in this synopsis, it has to be and can be stated that what makes for the affinities between psychological, literary and image-research approaches in research on the mirror is the shared...

  17. The diffuse interstellar medium

    Science.gov (United States)

    Cox, Donald P.

    1990-01-01

    The last 20 years of the efforts to understand the diffuse ISM are reviewed, with recent changes of fundamental aspects being highlighted. Attention is given to the interstellar pressure and its components, the weight of the ISM, the midplane pressure contributions, and pressure contributions at 1 kpc. What velocity dispersions, cosmic ray pressure, and magnetic field pressure that can be expected for a gas in a high magnetic field environment is addressed. The intercloud medium is described, with reference to the work of Cox and Slavin (1989). Various caveats are discussed and a number of areas for future investigation are identified. Steps that could be taken toward a successful phase segregation model are discussed.

  18. Prevention of adverse reactions to intravascular contrast media

    International Nuclear Information System (INIS)

    Soyer, P.; Levesque, M.

    1990-01-01

    The exact mechanisms of adverse reactions to contrast media are still imperfectly known. However, these reactions may be classified as idiosyncratic. Non-idiosyncratic reactions can be prevented by using new, non-ionic contrast agents. Idiosyncratic reactions can be prevented by specific premedication. Patients with a history of idiosyncratic reaction may benefit from corticosteroids and antihistamines administered prophylactically. Patients who seem to be more likely than others to react to contrast media must be premedicated, the risk of reaction being identified and evaluated by questioning. It has recently been suggested that all patients about to receive an intravascular injection of contrast medium should also be premedicated [fr

  19. T1 Shortening in the Globus Pallidus after Multiple Administrations of Gadobutrol: Assessment with a Multidynamic Multiecho Sequence.

    Science.gov (United States)

    Kang, Koung Mi; Choi, Seung Hong; Hwang, Moonjung; Yun, Tae Jin; Kim, Ji-Hoon; Sohn, Chul-Ho

    2018-04-01

    Purpose To determine the association between the administration of the macrocyclic contrast medium gadobutrol and T1 relaxation time in the brains of patients with normal renal function by using multidynamic multiecho (MDME) magnetic resonance (MR) imaging sequences. Materials and Methods The institutional review board approved this retrospective study, and the need to obtain written informed consent was waived. This study included 46 patients (revealed by an electronic medical record search) who had received one or more gadobutrol injections and a maximum of one MR imaging contrast medium injection other than gadobutrol before MDME sequence acquisition. One radiologist performed quantitative analyses of regions of interest on quantitative T1 maps twice to cover the normal-appearing globus pallidus (GP), frontal white matter, frontal cortex, and thalamus. The number of administrations and the cumulative dose of gadobutrol, age, intervals between administrations, sex, and treatment were investigated. Univariable and multivariable linear regression analyses of the T1 values in four brain regions and the GP-to-thalamus signal intensity (SI) ratio were performed. P values of less than the Bonferroni-corrected value of .01 were considered to indicate significant differences. Results Intraobserver reproducibility was good to excellent (intraclass correlation coefficients, 0.62-0.81). Because of high multicollinearity between the number of gadobutrol administrations and accumulated dose (r = 0.96, P .01). Conclusion Multiple exposures to gadobutrol are associated with T1 shortening in the GP. © RSNA, 2017 Online supplemental material is available for this article.

  20. Current concepts of contrast-induced nephropathy: A brief review

    Directory of Open Access Journals (Sweden)

    Chao-Fu Chang

    2013-12-01

    Full Text Available Contrast-induced nephropathy (CIN is a common hospital-acquired acute kidney injury. Published studies on this condition have dramatically increased in recent years. This article aims to provide a brief literature review. English articles published from 1983 to 2012 were retrieved from PubMed by searching using the term “contrast-induced nephropathy.” Patients with CIN were associated with increased resource utilization, prolonged hospital stay, and increased long-term mortality. CIN is defined as a ≥0.5 mg/dL rise in serum creatinine or a 25% increase, assessed within 48–72 hours after administration of contrast medium (CM. All patients receiving CM should be evaluated for their CIN risk, especially preexisting kidney disease. The CM should be prewarmed to 37 °C and injected at the lowest possible dose. Repeat injection within 72 hours should be avoided. Either iso-osmolar CM or low-osmolar CM, except ioxaglate or iohexol, can be used in all patients. Iso-osmolar CM iodixanol may be a better choice for high-risk patients with chronic kidney disease requiring intra-arterial administration. Nephrotoxic drugs should be stopped 2 days prior to when the patient undergoes a procedure. All patients receiving CM should be at an optimal volume status. Parenteral isotonic saline without any diuretic should be started 12 hours prior to CM at a rate of 1 mL/kg/h and continued for 24 hours if there is no contraindication. In patients who require shorter volume supplement periods or are at a higher risk, bicarbonate infusion (154 mEq/L, 3 mL/kg/h for 1 hour bolus prior to CM, followed by 1 mL/kg/h for 6 hours may be used as an alternative to isotonic saline. Oral N-acetylcysteine (600 mg bid, starting on the day prior to the procedure together with parenteral hydration is suggested for patients at risk. Hemodialysis/hemofiltration is only considered in chronic kidney disease stage 4/5 patients when an access is available. The other medications

  1. Transport phenomena in sharply contrasting media with a diffusion barrier

    International Nuclear Information System (INIS)

    Dvoretskaya, O A; Kondratenko, P S

    2011-01-01

    Using the advection–diffusion equation, we analytically study contaminant transport in a sharply contrasting medium with a diffusion barrier due to localization of a contaminant source in a low-permeability medium. Anomalous diffusion behavior and a crossover between different transport regimes are observed. The diffusion barrier results in exponential attenuation of the source power, retardation of the contaminant plume growth and modification of the concentration distribution at large distances. (paper)

  2. Mamografia com contraste

    OpenAIRE

    Baptista, Rita; Silva, Carina; Reis, Cláudia

    2016-01-01

    O estudo pretendeu apresentar as indicações clínicas, vantagens e princípios da mamografia com contraste, identificar as evoluyções tecnológicas para a mamografia com contraste e caracterizar as práticas e os desafios dos técnicos de radiologia do Hospital de Santarém (único no país a utilizar esta técnica). O cancro da mama é uma das principais causas de morte nas mulheres, em todo o mundo, mas principalmente nos Estados Unidos da América, Canadá, Europa Ocidental e Austrália. Em Portugal, e...

  3. Current iodinated contrast media

    International Nuclear Information System (INIS)

    Stacul, F.

    2001-01-01

    The number of scientific papers on iodinated contrast media is declining. Indeed, comparative trials between high-osmolality and low-osmolality agents largely showed the higher safety and tolerability of the latter, and this is no longer a matter of discussion. Only financial constraints could prevent a total conversion to low-osmolality agents. Research comparing low-osmolality (nonionic monomers, ionic dimer) and iso-osmolality contrast media (nonionic dimers) are still ongoing. Both classes of nonionic compounds proved safer than the ionic dimer. The relative merits of nonionic monomers and nonionic dimers are a matter for debate, and criteria for a selective use of different agents for different procedures could be discussed. (orig.)

  4. Abdominal vascular and visceral parenchymal contrast enhancement in MDCT: Effects of injection duration

    Energy Technology Data Exchange (ETDEWEB)

    Tsuge, Yusuke, E-mail: tsugeu@cup.ocn.ne.jp [Department of Radiology, Kizawa Memorial Hospital, 590 Kobityo Shimokobi, Minokamo City, Gifu 505-8503 (Japan); Kanematsu, Masayuki [Department of Radiology, Gifu University Hospital, Gifu (Japan); Department of Radiology Services, Gifu University Hospital, Gifu (Japan); Goshima, Satoshi; Kondo, Hiroshi [Department of Radiology, Gifu University Hospital, Gifu (Japan); Yokoyama, Ryujiro; Miyoshi, Toshiharu [Department of Radiology Services, Gifu University Hospital, Gifu (Japan); Onozuka, Minoru [Department of Physiology and Neuroscience, Kanagawa Dental College, Yokosuka (Japan); Moriyama, Noriyuki [Research Center for Cancer Prevention and Screening, National Cancer Center Hospital, Tsukiji (Japan); Bae, Kyongtae T. [Radiology and Biomedical Engineering, University of Pittsburgh, Pittsburgh, PA (United States)

    2011-11-15

    Purpose: To evaluate and compare the effect of short and long injection durations on aortic, pancreatic and hepatic enhancement in abdominal MDCT. Methods and materials: Triphasic contrast-enhanced CT images (16-MDCT, 1.25-mm collimation, 5-mm thickness, 6.1-s acquisition time for each phase) were obtained with 2 mL/kg injection of 300 mgI/mL iodine contrast material in 116 patients. Patients were prospectively randomized into two groups: one receiving contrast medium for 25-s injection duration and the other for 35-s injection duration. In both groups, triphasic scans were initiated 5, 15, and 40 s after the completion of contrast injection for the first, second and third phases, respectively. CT values (HU) in the abdominal aorta, liver, spleen, pancreas, splenic and superior mesenteric arteries, and veins (splenic, superior mesenteric, portal, and hepatic) were measured. Quantitative and qualitative analysis for the degree of contrast enhancement between the two groups in various organs was compared at each scan phase. Results: The aortic and arterial enhancements in the first-phase scan were higher for the 25-s group than those of the 35-s group (P < .001). Hepatic enhancement was higher for the 35-s group in the first (P < .001) and second (P < .01) phases, but no difference in the third-phase. No difference was found between the groups for the pancreatic enhancement at any phases. Qualitative results were in good agreement with quantitative results. Conclusion: Contrast administration with shorter injection duration increased peak aortic and arterial enhancement and contributed to improvement in the quality of CT angiograms, but for the solid abdominal organs 35-s protocol is recommended.

  5. Gadolinium-based contrast agents in pediatric magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gale, Eric M.; Caravan, Peter [Massachusetts General Hospital, Harvard Medical School, Department of Radiology, The Martinos Center for Biomedical Imaging, Boston, MA (United States); Rao, Anil G. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); McDonald, Robert J. [College of Medicine, Mayo Clinic, Department of Radiology, Rochester, MN (United States); Winfeld, Matthew [University of Pennsylvania Perelman School of Medicine, Philadelphia, PA (United States); Fleck, Robert J. [Cincinnati Children' s Hospital Medical Center, Department of Pediatric Radiology, Cincinnati, OH (United States); Gee, Michael S. [MassGeneral Hospital for Children, Harvard Medical School, Division of Pediatric Imaging, Department of Radiology, Boston, MA (United States)

    2017-05-15

    Gadolinium-based contrast agents can increase the accuracy and expediency of an MRI examination. However the benefits of a contrast-enhanced scan must be carefully weighed against the well-documented risks associated with administration of exogenous contrast media. The purpose of this review is to discuss commercially available gadolinium-based contrast agents (GBCAs) in the context of pediatric radiology. We discuss the chemistry, regulatory status, safety and clinical applications, with particular emphasis on imaging of the blood vessels, heart, hepatobiliary tree and central nervous system. We also discuss non-GBCA MRI contrast agents that are less frequently used or not commercially available. (orig.)

  6. Saphenous Venous Ablation with Hot Contrast in a Canine Model

    International Nuclear Information System (INIS)

    Prasad, Amit; Qian Zhong; Kirsch, David; Eissa, Marna; Narra, Pavan; Lopera, Jorge; Espinoza, Carmen G.; Castaneda, Wifrido

    2008-01-01

    Purpose. To determine the feasibility, efficacy, and safety of thermal ablation of the saphenous vein with hot contrast medium. Methods. Twelve saphenous veins of 6 dogs were percutaneously ablated with hot contrast medium. In all animals, ablation was performed in the vein of one leg, followed by ablation in the contralateral side 1 month later. An occlusion balloon catheter was placed in the infragenicular segment of the saphenous vein via a jugular access to prevent unwanted thermal effects on the non-target segment of the saphenous vein. After inflation of the balloon, 10 ml of hot contrast medium was injected under fluoroscopic control through a sheath placed in the saphenous vein above the ankle. A second 10 ml injection of hot contrast medium was made after 5 min in each vessel. Venographic follow-up of the ablated veins was performed at 1 month (n = 12) and 2 months (n = 6). Results. Follow-up venograms showed that all ablated venous segments were occluded at 1 month. In 6 veins which were followed up to 2 months, 4 (66%) remained occluded, 1 (16%) was partially patent, and the remaining vein (16%) was completely patent. In these latter 2 cases, an inadequate amount of hot contrast was delivered to the lumen due to a closed balloon catheter downstream which did not allow contrast to displace blood within the vessel. Discussion. Hot contrast medium thermal ablation of the saphenous vein appears feasible, safe, and effective in the canine model, provided an adequate amount of embolization agent is used

  7. Anisotropic contrast optical microscope.

    Science.gov (United States)

    Peev, D; Hofmann, T; Kananizadeh, N; Beeram, S; Rodriguez, E; Wimer, S; Rodenhausen, K B; Herzinger, C M; Kasputis, T; Pfaunmiller, E; Nguyen, A; Korlacki, R; Pannier, A; Li, Y; Schubert, E; Hage, D; Schubert, M

    2016-11-01

    An optical microscope is described that reveals contrast in the Mueller matrix images of a thin, transparent, or semi-transparent specimen located within an anisotropic object plane (anisotropic filter). The specimen changes the anisotropy of the filter and thereby produces contrast within the Mueller matrix images. Here we use an anisotropic filter composed of a semi-transparent, nanostructured thin film with sub-wavelength thickness placed within the object plane. The sample is illuminated as in common optical microscopy but the light is modulated in its polarization using combinations of linear polarizers and phase plate (compensator) to control and analyze the state of polarization. Direct generalized ellipsometry data analysis approaches permit extraction of fundamental Mueller matrix object plane images dispensing with the need of Fourier expansion methods. Generalized ellipsometry model approaches are used for quantitative image analyses. These images are obtained from sets of multiple images obtained under various polarizer, analyzer, and compensator settings. Up to 16 independent Mueller matrix images can be obtained, while our current setup is limited to 11 images normalized by the unpolarized intensity. We demonstrate the anisotropic contrast optical microscope by measuring lithographically defined micro-patterned anisotropic filters, and we quantify the adsorption of an organic self-assembled monolayer film onto the anisotropic filter. Comparison with an isotropic glass slide demonstrates the image enhancement obtained by our method over microscopy without the use of an anisotropic filter. In our current instrument, we estimate the limit of detection for organic volumetric mass within the object plane of ≈49 fg within ≈7 × 7 μm 2 object surface area. Compared to a quartz crystal microbalance with dissipation instrumentation, where contemporary limits require a total load of ≈500 pg for detection, the instrumentation demonstrated here improves

  8. Systems and methods for separating particles utilizing engineered acoustic contrast capture particles

    Science.gov (United States)

    Kaduchak, Gregory; Ward, Michael D.

    2018-03-06

    An apparatus for separating particles from a medium includes a capillary defining a flow path therein that is in fluid communication with a medium source. The medium source includes engineered acoustic contrast capture particle having a predetermined acoustic contrast. The apparatus includes a vibration generator that is operable to produce at least one acoustic field within the flow path. The acoustic field produces a force potential minima for positive acoustic contrast particles and a force potential minima for negative acoustic contrast particles in the flow path and drives the engineered acoustic contrast capture particles to either the force potential minima for positive acoustic contrast particles or the force potential minima for negative acoustic contrast particles.

  9. Practical issues in the prevention and treatment of contrast ...

    African Journals Online (AJOL)

    Kidney dysfunction is a serious complication that can occur following the administration of contrast media (CM). Although the incidence of contrast nephropathy (CN) is low in the general population (1 - 2%) it poses a serious risk to those with impaired kidney function. Other risks include diabetes, old age and dehydration.

  10. Alterations of serum potassium, serum magnesium and adenosine diphosphate due to various contrast media containing iodine

    International Nuclear Information System (INIS)

    Lehrberger, G.

    1979-01-01

    As an introduction of the chemical structure of contrast media is explained. Then follows a survey about the complication rates in examinations with intravascularly applicable iodine-containing contrast media. In the next part clinical symptoms and signs of general and localized contrast media incompatibility reactions, the contrast medium protein reaction and the relationship between allergic reaction and contrast medium are explained. It was tried to attribute the large amount of side-effects to one primary reaction. In this connection the three above-mentioned components were investigated. (orig./MG) [de

  11. Improvements in gastric diagnosis by using high density contrast media with low viscosity

    International Nuclear Information System (INIS)

    Toischer, H.P.

    1983-01-01

    In a retrospective clinical study, 150 unselected double contrast examinations of the stomach using conventional contrast media (100 g/100 ml barium sulphate) were compared with a similar number of examinations using a high density contrast medium of flow viscosity (250 g/100 ml barium sulphate). The high density contrast medium was distinctly better for demonstrating detail of the gastric mucosa. The uneveness of coating and instability of the older high density contrast media was observed in 15.5% of cases and, in no instance, did this make it impossible to reach a diagnosis. (orig.) [de

  12. Contrast Invariant SNR

    DEFF Research Database (Denmark)

    Weiss, Pierre; Escande, Paul; Dong, Yiqiu

    We design an image quality measure independent of local contrast changes, which constitute simple models of illumination changes. Given two images, the algorithm provides the image closest to the first one with the component tree of the second. This problem can be cast as a specific convex progra...... algorithms based on interior point methods. The algorithm has potential applications in change detection, color image processing or image fusion. A Matlab implementation is available at http://www.math.univ-toulouse.fr/_weiss/PageCodes.html....

  13. Contrast media safety-an update

    DEFF Research Database (Denmark)

    Thomsen, Henrik S

    2011-01-01

    The value of contrast agents has for long been documented by their common daily use in imaging departments worldwide. In principle, they should be injected and leave the body immediately after use in the same condition or undergo natural metabolism without making any harm to the patient. However......, this is not the case. It is of utmost importance to reduce the prevalence to as close as possible to zero. This can be done by identifying the patients at risk before administration of contrast agents. For acute non-renal adverse reactions, it is also important to be prepared for treating them instantly. The current...... review is a short state of the art regarding adverse reactions to contrast agents....

  14. Pharmacodynamics and tolerance of X-ray contrast media

    International Nuclear Information System (INIS)

    Schmiedel, E.

    1987-01-01

    The improved tolerance of nonionic contrast media compared with conventional contrast media is mainly due to their lower osmolality and reduced allergoid potential. Tolerance advantages that have been definitely proven are, for example, low-pain contrast medium injection and superior systemic tolerance; side effects of an allergic pattern occur less often. Animals experiments have established that nonionic contrast media exercise a comparatively lower influence on the cardiovascular system. The haemodynamics of pulmonary circulation are less adversely affected on intravenous bolus injection. Reduced potential risk is to be expected especially in cardiac and bronchopulmonary high-risk patients. The reduced nephrotoxicity of nonionic contrast media was definitely established by clinical studies. Further systematic studies will however be required to provide an answer to the question whether this also entails a reduction in the incidence of renal failures induced by contrast media. (orig.) [de

  15. Effects of radiographic contrast media on the serum complement system

    International Nuclear Information System (INIS)

    Tirone, P.; Boldrini, E.

    1983-01-01

    The authors explored the activation of the complement system produced by a nonionic organic iodine compound, namely iopamidol, which is proposed as a contrast medium for radiographic examination by intravenous and intra-arterial injection. The study was conducted in vitro versus established ionic contrasts (diatrizoate, iothalamate, acetrizoate) and a nonionic compound (metrizamide). The adopted experimental model was the immunohemolytic detector system, in which the immune complex consisted of goat erythrocytes sensitized with the corresponding antibody (hemolysin), and complement (C') was supplied by guinea pig serum. All the products caused complement activation. The results show that nonionic contrast media produce less activation of the complement system than the traditional ionic contrast. Thus the use of nonionic contrast for radiological procedures necessitating the introduction of contrast material into the blood compartment would imply a reduced risk of anaphylactoid reactions. (orig.)

  16. Contrast-enhanced MR imaging monitoring of acute tumor response to chemotherapy

    International Nuclear Information System (INIS)

    Ranney, D.F.; Cohen, J.M.; Antich, P.P.; Endman, W.A.; Kulkarni, P.; Weinreb, J.C.; Giovanella, B.

    1987-01-01

    Treatment responses of human malignant melanomas were monitored at millimeter resolution in athymic mice by injecting a new polymeric contrast agent, Gd-DTPA-dextran (0.1 mmol Gd/kg, intravenously). Proton MR imaging (0.35 T, spin-echo, repetition time = 0.5 second, echo time = 50 msec) was performed 30 hours after administering diphtheria toxin. Pre-contrast medium images revealed only homogeneous intermediate-intensity tumor masses. Post-contrast medium images of untreated (viable) tumors demonstrated 32% enhancement throughout the entire mass. Post-contrast medium images of toxin-treated tumors revealed marked enhancement (65%) of the histologically viable outer rims, lesser enhancement (38%) of heavily damaged subregions, and no enhancement of dead tumor. These acute, contrast medium-enhanced MR images accurately identified tumor subregions that survived for longer than one week

  17. Is the routine use of intravenous contrast justified in the workup of ...

    African Journals Online (AJOL)

    The indications for the administration of intravenous contrast media to adult patients presenting with firsttime seizures and a normal pre-contrast study are not clear. A retrospective audit of such patients was done and compared with the post-contrast study. In our study sample of 205 patients all the post-contrast scans were ...

  18. Interactive neonatal gastrointestinal magnetic resonance imaging using fruit juice as an oral contrast media

    International Nuclear Information System (INIS)

    Arthurs, Owen J; Graves, Martin J; Edwards, Andrea D; Joubert, Ilse; Set, Pat AK; Lomas, David J

    2014-01-01

    The objective was to evaluate the use of fruit juice with an interactive inversion recovery (IR) MR pulse sequence to visualise the gastrointestinal tract. We investigated the relaxation properties of 12 different natural fruit juices in vitro, to identify which could be used as oral contrast. We then describe our initial experience using an interactive MR pulse sequence to allow optimal visualisation after administering pineapple juice orally, and suppressing pre-existing bowel fluid contents, with variable TI in three adult and one child volunteer. Pineapple juice (PJ) had both the shortest T 1 (243 ms) and shortest T 2 (48 ms) of the fruit juices tested. Optimal signal differentiation between pre-existing bowel contents and oral PJ administration was obtained with TIs of between 900 and 1100 ms. The use of an inversion recovery preparation allowed long T 1 pre-existing bowel contents to be suppressed whilst the short T 1 of fruit juice acts as a positive contrast medium. Pineapple juice could be used as oral contrast agent for neonatal gastrointestinal magnetic resonance imaging

  19. Contrast enhancement of mail piece images

    Science.gov (United States)

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

    1992-08-01

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

  20. Mesons in the nuclear Medium

    CERN Document Server

    Kotulla, M

    2006-01-01

    We discuss recent experimental results on the modification of hadron properties in a nuclear medium. Particular emphasis is placed on an $\\omega$ production experiment performed by the CBELSA/TAPS collaboration at the ELSA accelerator. The data shows a smaller $\\omega$ meson mass together with a significant increase of its width in the nuclear medium.

  1. Phase Contrast Imaging

    DEFF Research Database (Denmark)

    1996-01-01

    The invention relates to a method and a system for synthesizing a prescribed intensity pattern based on phase contrast imaging that is not based on the assumption of prior art methods that the pahase shift phi is less than 1 radian. An improved method based on a simple imaging operation...... phasors attain predetermined values for predetermined spatial frequencies, and the phasor value of the specific resolution element of the spatial phase mask corresponds to a distinct intensity level of the image of the resolution element in the intensity pattern, and a spatial phase filter for phase...... shifting of a part of the electromagntic radiation, in combination with an imaging system for generation of the intensity pattern by interference in the image plane of the imaging system between the part of the electromagnetic raidation that has been phase shifted by the phase filter and the remaining part...

  2. Paramagnetic contrast material

    International Nuclear Information System (INIS)

    McNamara, M.T.

    1987-01-01

    Paramagnetic contrast materials have certainly demonstrated clinical utility in a variety of organ systems for improved detection of various neoplastic, inflammatory, infectious, and physiologic abnormalities. Although the more commonly employed extracellular agents, such as Gd-DTPA, have been quite safe and useful, particularly in the CNS, it is almost certain that other substances will achieve more success in various other organs, such as iron oxides in the reticuloendothelial system and persisting extracellular agents in the cardiovascular system. Finally, as MRI technology continues to evolve, producing such exciting new sequences as gradient-echo fast scans, the roles of currently existing and newly discovered paramagnetic pharmaceuticals must be continuously reevaluated both to obtain maximum clinical benefit and to guide the search for newer agents that may further optimize the diagnostic efficacy of MRI

  3. New MR contrast agent

    International Nuclear Information System (INIS)

    Grossman, C.D.; Subramanian, G.; Schneider, R.; Szeverenyi, N.E.; Rosenbaum, A.M.; Gagne, G.; Tillapaugh-Fay, G.; Berlin, R.; Ritter-Hrncirik, C.; Yu, S.

    1990-01-01

    This paper evaluates an MR contrast agent-meglumine tris-(2,6-dicarboxypyridine) gadolinium (III) or gadolinium dipicolinate (Gd-DPC)-produced in-house. Rats were anesthetized with pentobarbital. For renal imaging, bowel motion artifact was minimized with glucagon (0.014 mg/kg, intravenous (IV)). Enhanced images were generated on a 2-T chemical shift imaging system with a 31-cm horizontal bore magnet after IV injection of Gd-DPC (100 μM/kg). Coronal sections of the kidneys and sagittal sections of the brain, 2 mm thick, were made. Six to eight excitations and 128 or 356 phase-encoding steps were used for each image. Control animals were injected with equivalent doses of gadopentetate dimeglumine

  4. Gadolinium as a CT contrast agent: an experimental study for the effects of injection parameters in the rabbit brain model

    International Nuclear Information System (INIS)

    Kim, Hyun Jin; Choi, Hye Young; Lee, Sun Wha; Hwang, Ji Young

    2005-01-01

    We wanted to investigate the use of gadolinium based contrast agent (Gd-DTPA) for computed tomography (CT), and we also wanted to assess the effects of valuable injection parameters on enhancement in an experimental rabbit brain model. In vitro, attenuation measurements of serial dilutions of Gd-DTPA and iopromide were compared. In five rabbits, single level dynamic gadolinium-enhanced brain CT studies were obtained using different injection parameters. A comparision CT scan after iopromide administration was performed. The time-attenuation curves of the brain vessel and parenchyma were obtained and the magnitude of enhancement (Hmax) and the time to peak enhancement (Tmax) were analyzed. In vitro, the attenuation coefficient of undiluted Gd-DTPA (2,578 HU) was higher than that of iopromide (1,761 HU) at equimolar concentrations. In 5 rabbits, the time-attenuation curve demonstrated a distinct pattern with peak enhancement only in the brain vessel, but not in the brain parenchyma. There was increasing linear relationship between the injection rate of Gd-DTPA and Hmax, and a declining linear relationship with Tmax. The higher the concentration of Gd-DTPA, the higher Hmax was, but no significant difference was found for the Tmax. Higher volumes of Gd-DTPA revealed a higher Hmax and a delayed Tmax. Enhancement of the brain parenchyma on gadolinium-enhanced CT is minimal, while enhancement of the brain vessels is distinctive. The most important factor affecting Hmax of the vessel is the concentration of the contrast medium and the most important factor affecting Tmax of the vessel is volume of the contrast medium. The gadolinium-based contrast agent may be an reasonable alternative contrast agent for brain CT, and especially in cerebral vessels, and it may also be advantageous for brain parenchyma of those patients with BBB dysfunction

  5. Contrast media for radiological examination in gastrointestinal tract leakage

    NARCIS (Netherlands)

    A.Z. Ginai (Abida)

    1987-01-01

    textabstractThe aim of this investigation has been to find a safe and suitable contrast medium for radiological evaluation of the gastrointestinal tract in cases where leakage outside the GIT can be suspected. Leakage outside the gastro-intestinal tract lumen can occur in many ways eg.,

  6. 21 CFR 866.2390 - Transport culture medium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Transport culture medium. 866.2390 Section 866.2390 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2390 Transport culture...

  7. 21 CFR 864.8500 - Lymphocyte separation medium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8500 Lymphocyte separation...

  8. The interaction of radiographic contrast media with immune globulins

    International Nuclear Information System (INIS)

    Bauer, K.

    1983-01-01

    As a special form of contrast medium incidents, various reaction modes between iodinated contrast media and immunoglobulins are described. Theoretical explanations and typical examples are given for each of the four different possible action mechanisms. Diagnostic precautions are proposed in order to avoid unfavourable reactions especially with paraproteins. Special attention is drawn to the antigen-antibody like reaction between iodinated contrast media and IgM paraproteins. Some immunological criteria are recalled to attention, this type of reaction has to meet stringently. Only by this, misinterpretations of inevident conclusions from analogy can be prevented in future similar cases. (orig.) [de

  9. Comparative study of pneumocystography, positive contrast cystography and double contrast cystography in dogs

    International Nuclear Information System (INIS)

    Thibaut, J.; Parada, E.; Vargas, L.; Deppe, R.; Born, R.

    1997-01-01

    In order to compare three radiographic techniques: pneumocystography, positive contrast cystography and double contrast cystography, three series of 24 radiographs each in lateral and ventrodorsal projections were made. Six healthy adult male dogs with weight ranging between 7 and 16 kg were used. Food was withheld for 24 hours and two enemas were made before the series of radiographs were taken. Dogs were anaesthetized with sodium thiopental (20 mg/kg i.v.). The contrast medium was introduced through a urethral catheter. Pneumocystography was performed in the first series introducing air (10 ml/kg) in the bladder. Positive contrast cystography was performed in the second series introducing Hypaque M-60% diluted, contributing 100 mg of iodine per ml (10 ml/kg). In the double contrast cystography Hypaque M-60% diluted (10 ml) was introduced, in concentration of 150 mg of iodine per ml. Then air was introduced (10 ml/kg) through a catheter. Plates were taken in both projections at 1 and 10 minutes for each technique. The radiographic plates of each series were analized comparing the characteristics of radiographic density, outline and size. In neumocystography, positive contrast and double contrast cystography, the radiographic density was predominantly low, high and intermediate, respectively. The radiographic outline was mainly regular for the three techniques. With respect to bladder size, there was a decrease of height and an increase of length and width at 10 minutes. Comparing these three radiographic techniques, it can be concluded that the one that best outlines the bladder mucosa is double contrast. Pneumocystography provides the best image for opaque structures and cystography best shows the position of the urinary bladder [es

  10. Administrative Appeals and ADR in Danish Administrative Law

    DEFF Research Database (Denmark)

    Conradsen, Inger Marie; Gøtze, Michael

    2014-01-01

    Administrative Appeals, review, administrative tribunals, ombudsman, alternative dispute resolution......Administrative Appeals, review, administrative tribunals, ombudsman, alternative dispute resolution...

  11. Dual Contrast - Magnetic Resonance Fingerprinting (DC-MRF): A Platform for Simultaneous Quantification of Multiple MRI Contrast Agents.

    Science.gov (United States)

    Anderson, Christian E; Donnola, Shannon B; Jiang, Yun; Batesole, Joshua; Darrah, Rebecca; Drumm, Mitchell L; Brady-Kalnay, Susann M; Steinmetz, Nicole F; Yu, Xin; Griswold, Mark A; Flask, Chris A

    2017-08-16

    Injectable Magnetic Resonance Imaging (MRI) contrast agents have been widely used to provide critical assessments of disease for both clinical and basic science imaging research studies. The scope of available MRI contrast agents has expanded over the years with the emergence of molecular imaging contrast agents specifically targeted to biological markers. Unfortunately, synergistic application of more than a single molecular contrast agent has been limited by MRI's ability to only dynamically measure a single agent at a time. In this study, a new Dual Contrast - Magnetic Resonance Fingerprinting (DC - MRF) methodology is described that can detect and independently quantify the local concentration of multiple MRI contrast agents following simultaneous administration. This "multi-color" MRI methodology provides the opportunity to monitor multiple molecular species simultaneously and provides a practical, quantitative imaging framework for the eventual clinical translation of molecular imaging contrast agents.

  12. MR mammography: influence of menstrual cycle on the dynamic contrast enhancement of fibrocystic disease

    Energy Technology Data Exchange (ETDEWEB)

    Rieber, A.; Nuessle, K.; Merkle, E.; Tomczak, R.; Brambs, H.J. [Ulm Univ. (Germany). Abt. Radiologie 1 (Roentgendiagnostik); Kreienberg, R. [Ulm Univ. (Germany). Dept. of Gynecology

    1999-08-01

    Magnetic resonance mammography (MRM) provides data regarding the nature of tumours based on contrast medium dynamics; fibrocystic changes in the breast, however, may lead to false-positive results. This study investigated whether the contrast medium dynamics of fibrocystic changes are dependent on the menstrual cycle. Twenty-four patients with palpable lumps but normal mammographies and ultrasound studies were examined. The MRM technique was performed during the first and second part of the menstrual cycle using a FLASH 3D sequence, both native and at 1, 2, 3 and 8 min after intravenous application of 0.15 mmol/kg body weight of gadodiamide. The calculated time-intensity curves were evaluated based on the following criteria: early percentage of contrast medium uptake in relation to the native value; formation of a plateau phenomenon after the second minute; the point of maximal contrast medium uptake; and calculation of the contrast enhancing index. During the second half of the menstrual cycle, a generally greater contrast medium uptake was observed. Nevertheless, when further diagnostic criteria, such as continuous contrast medium increase as a function of time, were considered, there was no increased rate of false-positive findings. The phase of the menstrual cycle may affect the specificity of the examination, if only the quantitative contrast medium uptake and the percentage of contrast medium uptake in the first 2 min are considered. A control MRM during the other half of the cycle may then be indicated and additional diagnostic criteria may improve specificity. (orig.) With 2 figs., 2 tabs., 24 refs.

  13. Pions in the nuclear medium

    International Nuclear Information System (INIS)

    Chanfray, G.

    1996-07-01

    We discuss various aspects of pion physics in the nuclear medium. We first study s-wave pion-nucleus interaction in connection with chiral symmetry restoration and quark condensate in the nuclear medium. We then address the question of p-wave pion-nucleus interaction and collective pionic modes in nuclei and draw the consequences for in medium ππ correlations especially in the scalar-isoscalar channel. We finally discuss the modification of the rho meson mass spectrum at finite density and/or temperature in connection with relativistic heavy ion collisions

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

    International Nuclear Information System (INIS)

    Moriyama, Takashi; Suzuki, Shigeharu; Nakaoka, Tsutomu

    1981-01-01

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

  15. Is hepatotropic contrast enhanced MR a more effective method in differential diagnosis of hemangioma than multi-phase CT and unenhanced MR?

    Directory of Open Access Journals (Sweden)

    Markiet Karolina

    2011-04-01

    Full Text Available Abstract Background Cavernous hemangiomas are the most frequent neoplasms of the liver and in routine clinical practice they often need to be differentiated from malignant tumors and other benign focal lesions. The purpose of this study is to evaluate whether diagnostic accuracy of magnetic resonance imaging (MRI of hepatic hemangiomas, showing atypical pattern on US, improves with the use of Gd-BOPTA in comparison with contrast-enhanced multi-phase computed tomography (CT. Methods 178 consecutive patients with ambiguous hepatic masses showing atypical hyperechoic pattern on grey-scale US, underwent unenhanced and contrast-enhanced multi-phase multi-detector CT and MR (1.5T with the use of liver-specific contrast medium gadobenate dimeglumine (Gd-BOPTA. After intravenous contrast administration arterial (HAP, venous-portal (PVP, equilibrium phases (EP both in CT and MR and additionally hepatobiliary phase (HBP in MR were obtained. 398 lesions have been detected including 99 hemangiomas and 299 other lesions. Results In non-enhanced MDCT examination detection of hemangiomas was characterized by sensitivity of 76%, specificity of 90%, PPV of 71%, NPV of 92% and accuracy of 86%. Non-enhanced MR examination showed sensitivity of 98%, specificity of 99%, PPV of 99%, NPV of 99% and accuracy of 99%. After intravenous administration of contrast medium in MR the mentioned above parameters did not increase significantly. Conclusion Gd-BOPTA-enhanced MR in comparison with unenhanced MRI does not improve diagnostic accuracy in discriminating hemangiomas that show non-specific appearance in ultrasound examination. Unenhanced MR as a method of choice should directly follow US in course of diagnostic algorithm in differentiation of hemangiomas from other liver tumors.

  16. Late adverse reactions to intravascular iodine based contrast media

    DEFF Research Database (Denmark)

    Bellin, Marie-France; Stacul, Fulvio; Webb, Judith A W

    2011-01-01

    DEFINITION: Late adverse reactions (LAR) to contrast media (CM) are defined as reactions occurring 1 h to 1 week after exposure. NEED FOR REVIEW: In view of more prospective studies of LAR and new data about their pathophysiology, the Contrast Medium Safety Committee (CMSC) of the European Society...... or delayed reading intradermal). The main risk factors for LAR are a previous reaction to contrast medium, a history of allergy, and interleukin-2 treatment. Most skin reactions are mild or moderate and self-limiting. MANAGEMENT: Management is symptomatic and similar to the management of other drug......-induced skin reactions. To reduce the risk of repeat reactions avoidance of the relevant CM and any cross-reacting agents identified by skin testing is recommended....

  17. Liberation of plasma histamine after application of non-ionic contrast media

    International Nuclear Information System (INIS)

    Weiss, H.D.; Jansen, O.; Schallock, J.

    1989-01-01

    In 94 patients the levels of plasmahistamine have been measured after application of three non-ionic contrast media (Iopromid, Iopamidol, Iohexol) and after application of blood-isotonic saline solution. A significant liberation of histamine could be observed after administration of contrast media and also after administration of saline solution. Neither between the three nonionic contrast media nor between the contrast media and the saline solution significant differences could be measured. Administering contrast media after subsequently saline solution the levels of histamine were lower than in case of pure contrast media application. A psychogen induced histamine liberation is discussed. (orig.) [de

  18. Contrast enhancement of cerebral infarcts. Incidence and clinical value in different states of cerebral infarction

    International Nuclear Information System (INIS)

    Skriver, E.B.; Olsen, T.S.

    1982-01-01

    Information obtained from CT scan after contrast administration was evaluated in 59 consecutive stroke patients. CT scans before and after contrast administration were performed 3 days and 2 1/2 weeks after stroke. A plain CT scan was repeated 6 months later. Contrast enhancement was practically not seen on the first examination, but was seen in 46% on the second examination. There was a close relationship between the occurrence of contrast enhancement and the so called fogging effect. Contrast scanning gave additional information only when this effect was present. Plain CT scans 3 days after stroke were superior to contrast scans taken at any time for detecting and visualizing cerebral infarcts. (orig.)

  19. MRI contrast agent concentration and tumor interstitial fluid pressure.

    Science.gov (United States)

    Liu, L J; Schlesinger, M

    2016-10-07

    The present work describes the relationship between tumor interstitial fluid pressure (TIFP) and the concentration of contrast agent for dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). We predict the spatial distribution of TIFP based on that of contrast agent concentration. We also discuss the cases for estimating tumor interstitial volume fraction (void fraction or porosity of porous medium), ve, and contrast volume transfer constant, K(trans), by measuring the ratio of contrast agent concentration in tissue to that in plasma. A linear fluid velocity distribution may reflect a quadratic function of TIFP distribution and lead to a practical method for TIFP estimation. To calculate TIFP, the parameters or variables should preferably be measured along the direction of the linear fluid velocity (this is in the same direction as the gray value distribution of the image, which is also linear). This method may simplify the calculation for estimating TIFP. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  20. Are intravenous injections of contrast media really less nephrotoxic than intra-arterial injections?

    Energy Technology Data Exchange (ETDEWEB)

    Nyman, Ulf [University of Lund, Department of Diagnostic Radiology, Trelleborg (Sweden); Almen, Torsten [Skaane University Hospital, Department of Clinical Sciences/Medical Radiology, University of Lund, Malmoe (Sweden); Jacobsson, Bo [University of Gothenburg and the Sahlgrenska Academy, Department of Diagnostic Radiology, The Queen Silvia Children' s Hospital, Goeteborg (Sweden); Aspelin, Peter [Karolinska Institute and University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden)

    2012-06-15

    We oppose the opinion that the intra-arterial administration of iodine-based contrast media (CM) appears to pose a greater risk of contrast medium-induced nephropathy (CIN) than intravenous administration since (1) in intra-arterial coronary procedures and most other intra-arterial angiographic examinations, CM injections are also intravenous relative to the kidneys, (2) there is a lack of comparative trials studying the risk of CIN between intra-arterial and intravenous procedures with matched risk factors and CM doses, (3) a bias selection of patients with fewer risk factors may explain the seemingly lower rate of CIN after CT in comparison with coronary interventions, (4) the rate of CIN following intra-arterial coronary procedures may also be exaggerated owing to other causes of acute kidney failure, such as haemodynamic instability and microembolisation, (5) roughly the same gram-iodine/GFR ratio ({approx}1:1) as a limit of relatively safe CM doses has preliminarily been found for both intravenous CT and intra-arterial coronary procedures and (6) the substantially higher injected intravenous CM dose rate during CT relative to an intra-arterial coronary procedure might actually pose a higher risk of CIN following CT. Key Points circle Most intra-arterial injections of contrast media are intravenous relative to the kidneys. circle No evidence that intravenous CM injections should be less nephrotoxic than intra-arterial. circle Considerably higher dose rates of CM are used for CT relative to intra-arterial procedures. circle Higher dose rates may pose higher nephrotoxic risk for intravenous based CT studies. (orig.)

  1. Physical experiments on the utility of non-iodine-containing contrast media

    International Nuclear Information System (INIS)

    Kirschner, H.; Burmester, U.; Stringaris, K.; Jentsch, F.

    1979-01-01

    Because of the excellent ability of the CT scanner in analyzing absorption, the use of non-iodine-containing contrast media will be discussed. Experimental studies of the chemical elements with the atomic number Z = 1-83 with a scan tension of 120 kV were made to determine how many atoms of a given element are necessary to replace one iodine atom in an iodine-containing contrast medium, whereby the same contrast enhancement in the scan picture as with the iodine-containing contrast medium is produced. (orig.) 891 ORU/orig. 892 MB [de

  2. Comparison of in vitro histamine release by ionic and nonionic radiographyic contrast media

    International Nuclear Information System (INIS)

    Faraj, B.A.; Martin, L.G.

    1989-01-01

    This paper discusses a study whose results showed that in 53 hospitalized patients undergoing cardiovascular catheterization, incubation of their blood samples with varying concentrations of an ionic contrast medium (Angiovist-370, 60--631 mM) induced a significant (P < .005) amount of histamine release from whole blood (3.5%--10%), as compared with the histamine release following incubation with a nonionic contrast medium. Data suggest that the use of nonionic contrast media may induce minimal histamine release and thereby involve less patient risk from the histamine-mediated allergic and hemodynamic side effects associated with radiographic contrast media procedures

  3. Phase Contrast Imaging

    International Nuclear Information System (INIS)

    Menk, Ralf Hendrik

    2008-01-01

    All standard (medical) x-ray imaging technologies, rely primarily on the amplitude properties of the incident radiation, and do not depend on its phase. This is unchanged since the discovery by Roentgen that the intensity of an x-ray beam, as measured by the exposure on a film, was related to the relative transmission properties of an object. However, recently various imaging techniques have emerged which depend on the phase of the x-rays as well as the amplitude. Phase becomes important when the beam is coherent and the imaging system is sensitive to interference phenomena. Significant new advances have been made in coherent optic theory and techniques, which now promise phase information in medical imaging. The development of perfect crystal optics and the increasing availability of synchrotron radiation facilities have contributed to a significant increase in the application of phase based imaging in materials and life sciences. Unique source characteristics such as high intensity, monochromaticity, coherence and high collimating provide an ideal source for advanced imaging. Phase contrast imaging has been applied in both projection and computed tomography modes, and recent applications have been made in the field of medical imaging. Due to the underlying principle of X-ray detection conventional image receptors register only intensities of wave fields and not their phases. During the last decade basically five different methods were developed that translate the phase information into intensity variations. These methods are based on measuring the phase shift φ directly (using interference phenomena), the gradient ∇ φ , or the Laplacian ∇ 2 φ. All three methods can be applied to polychromatic X-ray sources keeping in mind that the native source is synchrotron radiation, featuring monochromatic and reasonable coherent X-ray beams. Due to the vast difference in the coefficients that are driven absorption and phase effects (factor 1,000-10,000 in the energy

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

  5. Organizational liability for adverse reactions to the contrast media

    International Nuclear Information System (INIS)

    Lim, Chang Seon

    2007-01-01

    Contrast medium is a very useful tool for X-ray examinations. But contrast medium has some unavoidable adverse reactions. For those patients who have never received contrast medium before, it is impossible to predict whether they will suffer from certain kinds of adverse reactions. Thus, radiologists should use strategies to minimize adverse events and be prepared to promptly recognize and manage any reactions to the contrast media. If a radiologist commits medical malpractice, he will face civil responsibility. Medical malpractice means a tort or breach of contrast that occurs in a medical setting. Medical malpractices happen, despite the efforts of hospital staff. Many courts have applied the traditional doctrine of respondeat superior in actions against organizations for injuries caused by their employees. It is a legal doctrine, which states that an employer is responsible for employee actions performed within the course of the employment. A hospital is an organization for health purposes. An organization may be convicted of an offense committed by an employee of the organization acting in its behalf and within the scope of this office or employment. Organizational liability involves a wide variety of legal issues, including tort liability, wrongful employment practices, personal injury, breach of fiduciary duty, and so on. Many executive directors of organizations are aware of their personal and organizational risks of exposure to legal liabilities. The employer must have the right to control the physical conduct of the employee and must consent to receive the employee's services, while expecting some benefits from the services offered. Therefore, legal liability can be imposed for improper selection, assignment, training, and supervision of employees. In conclusion, the hospital itself has organizational liability for adverse reactions to the contrast medium

  6. Medium modifications of vector mesons

    International Nuclear Information System (INIS)

    Pant, L.M.

    2004-01-01

    The omega photoproduction in nuclear medium with the ELSA facility at Bonn and the present status of the HADES collaboration to investigate the in-medium hadron properties in proton, heavy ions and hadron induced reactions at GSI, Darmstadt are presented. Efforts are under way to utilise the electron beam at Indore for experimental hadron physics in order to step into the intermediate energy nuclear physics regime. The skeletal outline of the high energy electron beam now available at CAT, Indore is discussed

  7. Medium effects in direct reactions

    International Nuclear Information System (INIS)

    Karakoc, M; Bertulani, C

    2013-01-01

    We discuss medium corrections of the nucleon-nucleon (NN) cross sections and their influence on direct reactions at intermediate energies ≳50 MeV/nucleon. The results obtained with free NN cross sections are compared with those obtained with a geometrical treatment of Pauli-blocking and Dirac-Bruecker methods. We show that medium corrections may lead to sizable modifications for collisions at intermediate energies and that they are more pronounced in reactions involving weakly bound nuclei.

  8. Post double-contrast sigmoid flush: An adjuvant technique in imaging diverticular disease

    International Nuclear Information System (INIS)

    Lappas, J.C.; Maglinte, D.D.T.; Kopecky, K.K.; Cockerill, E.M.; Lehman, G.A.

    1987-01-01

    In a prospective study, the effect of a low-density contrast medium infusion was evaluated as an adjunct to high-density double-contrast medium sigmoid imaging. Following a double-contrast medium barium enema (DCBE), 52 consecutive patients with sigmoid diverticulosis received an additional 500-700-mL enema with either water or a 1.5%CT barium suspension. Rectosigmoid films were evaluated for luminal distention, visualization of the interhaustral space, definition of diverticula, and interpretation of polypoid defects. While double-contrast medium views were excellent in 21%, improvement in multiple factors by water or 1.5% barium flush resulted in improved sigmoid images in 65% and 73% of patients, respectively. Polyps may be confirmed and artifactual defects confidently excluded. Sigmoid flush, particularly with low-density barium, is a simple adjunct to DCBE that improves visualization of the diverticular sigmoid

  9. The Value of Contrast Echocardiography

    Directory of Open Access Journals (Sweden)

    Shannon C. Treiber

    2016-01-01

    Full Text Available Purpose: There is much evidence-based research proving the effectiveness of contrast echocardiography, but there are still questions and concerns about its specific uses. This study tested the effectiveness of contrast echocardiography in defining the left ventricular endocardial border. Methods: From 30 patients, a total of 60 echocardiograms –– 30 with and 30 without use of contrast –– were retrospectively reviewed by four blinded cardiologists with advanced training in echocardiography. No single cardiologist reviewed contrast and noncontrast images of the same patient. Each set of 30 echocardiograms was then studied for wall-motion scoring. Visualization of left ventricular wall segments and a global visualization confidence level of interpretation were recorded. Results: Of all wall segments (N = 510, 91% were visualized in echocardiograms with use of contrast, whereas 75% of the walls were visualized in echocardiograms without contrast (P < 0.001. Of 30 examinations, 17 contrast echocardiograms were read with high confidence compared to 6 without contrast use (P = 0.004. The number of walls visualized with contrast was increased in 18 patients (60%, whereas noncontrast echocardiograms yielded more visualized walls in 6 patients (20%, P = 0.002. Conclusions: This study demonstrates that contrast is valuable to echocardiographic imaging. Its use should be supported throughout echocardiography clinics and encouraged in certain patients for whom resting and stress echocardiography results without contrast often prove uninterpretable.

  10. Refinement of the AdEPT Medium-Energy Gamma-Ray Science

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to explore the theoretical framework for the relatively unexplored field of medium energy (5--200 MeV) gamma-ray astronomy for a mission concept...

  11. Automated Extraction of Crop Area Statistics from Medium-Resolution Imagery, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will focus on the strategic, routine incorporation of medium-resolution satellite imagery into operational agricultural assessments for the global crop...

  12. Nimbus-2 Level 2 Medium Resolution Infrared Radiometer (MRIR) V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nimbus II Medium Resolution Infrared Radiometer (MRIR) was designed to measure electromagnetic radiation emitted and reflected from the earth and its atmosphere...

  13. Contrast-enhanced MRI of the lung

    International Nuclear Information System (INIS)

    Kauczor, Hans-Ulrich; Kreitner, Karl-Friedrich

    2000-01-01

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

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  15. Homogenization of High-Contrast Brinkman Flows

    KAUST Repository

    Brown, Donald L.

    2015-04-16

    Modeling porous flow in complex media is a challenging problem. Not only is the problem inherently multiscale but, due to high contrast in permeability values, flow velocities may differ greatly throughout the medium. To avoid complicated interface conditions, the Brinkman model is often used for such flows [O. Iliev, R. Lazarov, and J. Willems, Multiscale Model. Simul., 9 (2011), pp. 1350--1372]. Instead of permeability variations and contrast being contained in the geometric media structure, this information is contained in a hi