Nycomed Imaging AS Research Articles

The Cobweb Sign: Percutaneous Silastic Long Line Tip Placement in Tributaries of Superficial Veins

We report a method for preventing misplacement of percutaneous silastic catheters in superficial vein tributary or venous plexus. Catheters inserted less than the length calculated by surface anatomy measurement due to resistance were studied in three patients. Contrast X-rays (Omnipaque, Nycomed Imaging AS, Oslo, Norway) of the catheters was performed to confirm the catheter tip placement position. On initial assessment, the catheter tip placement was thought to be satisfactory and infusion of TPN commenced. Following signs of extravasation, re-examination of the contrast X-rays demonstrated that multiple thin rays of omnipaque could be traced in different directions like a cobweb. In the third infant, we recognised the "cobweb" sign and prospectively withdrew the catheter tip 2 cm. Repeat contrast X-ray confirmed that the catheter tip was in a major superficial vein, infusion continued without further complication. We conclude that when the "cobweb" sign is noticed then the catheter should be removed or withdrawn 2 to 3 cm and repeat contrast X-ray performed..

Dynamic MRI Enhanced with Albumin–(Gd-DTPA)30 or Ultrasmall Superparamagnetic Iron Oxide Particles (NC100150 Injection) for the Measurement of Microvessel Permeability in Experimental Breast Tumors

Characteristics of the cell nuclei within human breast tumors, as assayed and scored by the Scarff-Bloom-Richardson (SBR) histopathologic method, correlate with patient prognosis and long-term survival rates (1,2). We have shown previously in rodent mammary tumors that the histopathologic tumor grade correlates with quantitative magnetic resonance imaging (MRI)–derived estimates of tumor microvascular permeability obtained using a prototypic macromolecular contrast medium, albumin–(GdDTPA)30 (3). Microvessel permeability depends on functional and morphologic characteristics of cancer vessels and on physicochemical properties of the injected solute/ contrast medium molecule (4–7). In this study, we focus on specific characteristics of two contrast media and their influence on MRI-derived estimates of microvessel characteristics. The increased permeability of tumor vessels to macromolecular solutes has been demonstrated repeatedly using albumin–(Gd-DTPA)30, which is used in this study as a reference standard (8–10). Although not previously tested as probes of endothelial hyperpermeability, ultrasmall superparamagnetic iron oxide (USPIO) particles, having a mean diameter of approximately 20 nm, were compared in this study to albumin–(Gd-DTPA)30, which is approximately 20% the size of USPIO. Unlike albumin–(Gd-DTPA)30, which is incompletely eliminated and potentially immunogenic, USPIO particles have a favorable pharmacologic and tolerance profile and are now being tested clinically (11). Thus, the purpose of this study was to define the potential of USPIO (represented by NC100150 Injection [Nycomed Imaging AS, Oslo, Norway]) for the quantitative characterization of tumor microvasculature, specifically for measures of the microvessel permeability and the plasma volume. Results were compared to estimates derived with the established macromolecular contrast medium, albumin–(Gd-DTPA)30, and to the histologic tumor grade.

Use of the intravascular contrast agent NC100150 injection in spin-echo and gradient-echo imaging of the heart.

This is the first study of the intravascular iron oxide particle contrast agent, NC100150 Injection (Nycomed Imaging AS, Oslo, Norway, a part of Nycomed Amersham) in magnetic resonance imaging of the human heart. Eighteen healthy male volunteers were studied at both 0.5 and 1.5 T before and after the administration of NC100150 Injection. Transaxial spin-echo images were acquired at both field strengths, conventional gradient-echo cine images at 0.5 T, and breathhold Turbo-FLASH cine images at 1.5 T. Optimized cine imaging sequences were used postcontrast, with a high flip angle of 60-70 degrees. In the spin-echo images there was a significant reduction in the blood pool flow artifact at the level of the right atrium (0.5 T, 57%, p < 0.01; 1.5 T, 41%, p = 0.01) and the left ventricle (LV) (0.5 T, 45%, p = 0.01; 1.5 T, 45%, p < 0.01). In the conventional gradient-echo cines at 0.5 T, there was a significant increase in the LV blood pool and myocardial signal difference-to-noise ratio (SDNR) in the diastolic (56%, p = 0.01) and systolic (141%, p < 0.001) frames. There was also a significant increase in the signal intensity (SI) gradient at the LV blood pool-myocardial border in the diastolic and systolic frames (both p < 0.001). At higher doses of NC100150 Injection (3 and 4 mg/kg), a rim of signal void around the LV blood pool was observed, perfectly defining the LV blood pool-myocardial border. In the Turbo-FLASH breathhold cines at 1.5 T, there was a significant increase in the LV blood pool-myocardial SDNR in the diastolic (221%, p < 0.001) and systolic (916%, p < 0.001) frames. Again, there was also a significant increase in the SI gradient at the LV blood pool-myocardial border in the diastolic and systolic frames (both p = 0.003). In conclusion, NC100150 Injection was given safely to 18 healthy subjects. Image quality and LV blood pool-myocardial definition were improved after the administration of NC100150 Injection. These improvements enable better spin-echo anatomical definition, better definition of myocardial wall motion, and should improve the capability of automated edge detection algorithms.

Iopentol (Imagopaque® 350) compared with iohexol (Omnipaque® 350) in pediatric cardioangiography A clinical trial assessing adverse events, ECG, blood pressure and diagnostic information

A non-ionic, monomeric, low-osmolar contrast medium, iopentol (Imagopaque, Nycomed Imaging AS, Oslo, Norway) has been compared with iohexol (Omnipaque, Nycomed Imaging AS, Oslo, Norway) in a double-blind, randomized, parallel-group trial in children. The aims of the study were to compare the safety and radiographic efficacy of iopentol 350 mg I/ml versus those of iohexol 350 mg I/ ml in pediatric cardioangiography. Seventy-three children, of whom 35 received iopentol and 38 iohexol, were included in the evaluation. The quality of overall diagnostic information was excellent or adequate in all patients. There were no statistically significant differences between numbers of patients reporting adverse events nor number of patients reporting discomfort in the two groups. Three patients in the iopentol group and two patients in the iohexol group reported adverse events. Heat sensation was reported by 4 patients in the iopentol group and 5 patients in the iohexol group. Following injection of contrast medium, there were no differences between the groups regarding ECG, heart rate and systolic blood pressure at the site of injection. Iopentol was demonstrated to be as effective, safe and well tolerated as iohexol in pediatric cardioangiography.

Size fractionation of gas-filled microspheres by flotation

A dynamic model has been developed for the size fractionation process of gas-filled microspheres by flotation. The aim of this dynamic model is to control the fractionation process in an Nycomed Imaging AS Infoson ™ production plant. A general population balance is established for the dispersed phase that is later simplified for the specific particle suspension and process equipment used. This dynamic model has been tested against experimental data and shows a good correlation between the predicted and measured values. This paper describes both the physical phenomena and the modeling method.

In vivo stability and excretion of gadodiamide (GdDTPA-BMA), a hydrophilic gadolinium complex used as a contrast enhancing agent for magnetic resonance imaging

The stability and excretion of [14C]-gadodiamide (GdDTPA-BMA) was studied in male rats after i.v. injection of 0.3 mmol/kg [14C]-GdDTPA-BMA (Gd-diethylenetriaminepentaacetic-acid-bis-methylamide) formulated as gadodiamide injection (OMNISCAN, Nycomed Imaging AS, Oslo, Norway). Samples of blood and urine obtained within 60 min and 6 h postdosing, respectively, were analyzed for radiolabeled compounds. Analysis of GdDTPA-BMA in high and low molecular weight fractions of serum indicated no protein binding. HPLC analyses of urine samples obtained 0-2 h, 2-4 h and 4-6 h after injection revealed no detectable amounts of biotransformation products of GdDTPA-BMA. Serum samples obtained 30 min and 60 min after injection contained 9-13 microM of an unidentified compound which had a retention time different from all conceivable metabolites of gadodiamide. A similar concentration of this unknown compound was found in spiked predose serum samples. The total amount of the unknown compound in serum was less than 1% of the injected dose of [14C]-gadodiamide injection. It is concluded that gadodiamide, when administered i.v. as gadodiamide injection at a dosage of 0.3 mmol/kg, is stable in vivo and that the very major part of the dose (> 99%) is excreted in urine as an unchanged complex.

Iodixanol in intravenous urography: A comparison of iodixanol 270 mgI/ml, iodixanol 320 mgI/ml and iopamidol 300 mgI/ml (NIOPAM ™)

The first European trial of iodixanol (Nycomed Imaging AS) in adult intravenous urography is reported. Iodixanol is a new non-ionic, dimeric contrast medium of low osmolality. A double-blind, randomized, three group parallel study comparing iodixanol 270 mgI/ml, iodixanol 320 mgI/ml and iopamidol 300 mgI/ml (Niopam) was undertaken. A total of 173 of 180 patients entered completed the trial. Efficacy was evaluated with regard to overall diagnostic information and pyelographic density 5 min after contrast medium administration. Efficacy was found to increase with increasing iodine concentration, with no significant difference between the three contrast media. The incidence of adverse events was low, with no significant difference between the groups. Discomfort occurred less frequently with iodixanol than with iopamidol. We conclude that iodixanol is a safe and efficacious contrast medium for use in intravenous urography.

Human albumin base echocontrast agents—repeated use in animals may induce anaphylactic reactions

Our attention was drawn to an abstract in the Proceedings of the BMUS meeting in the British Journal of Radiology by J S Boyd at the Department of Veterinary Anatomy, University of Glasgow Veterinary School [1]. It was suggested that recently developed echocontrast agents may be of potential value for use in domestic animals. Albunex™, one of these contrast agents which has been developed by Nycomed Imaging AS in cooperation wityh Molecular Biosystems Inc., San Diego, consists of small air-filled albumin microspheres suspended in human albumin solution (5%).

Repeated intracoronary injections of contrast media. Additive hemodynamic and electrophysiologic effects in a dog model.

Coronary arteriography in patients implies several selective injections into the coronary arteries. The authors investigate whether repeated injections cause additive cardiac hemodynamic and electrophysiologic effects in dogs. Five repeated injections of 5 mL iohexol (Omnipaque 350 mgI/mL, Nycomed Imaging AS, Oslo, Norway), ioxaglate (Hexabrix 320 mgI/mL, Laboratory Guerbet, Cedex, France), and sodium meglumine-diatrizoate (Renografin-76 370 mgI/mL, Squibb Diagnostics, Princeton, NJ) were given into the left coronary artery in 7 anesthetized dogs and were compared with the effects after a 5 mL single injection of the same medium. Left ventricular (LV) pressures, LV dP/dtmax (inotropy) and epicardial monophasic action potential were recorded, from which monophasic action potential duration (MAPD) was measured. Repeated injections of ioxaglate and sodium meglumine-diatrizoate did not potentiate initial decrease in LV pressures and inotropy, but the secondary increase in LV inotropy increased more after repeated injections than after a single injection. Repeated injections of iohexol increased LV inotropy more than a single injection. All contrast media prolonged MAPD more after repeated injections than after single injections. MAPD was prolonged 30 sec after the last injection. Repeated injections of contrast media cause greater cardiac hemodynamic and electrophysiologic effects than a single injection during selective coronary arteriography.

Biodistribution and toxicity of MR imaging contrast media

Journal of Magnetic Resonance ImagingVolume 3, Issue 1 p. 157-165 Review Biodistribution and toxicity of MR imaging contrast media Audun N. Oksendal PhD, Corresponding Author Audun N. Oksendal PhD Nycomed Imaging AS, PO Box 4220 Torshov, Nycoveien 2, N-0401, Oslo, NorwayNycomed Imaging AS, PO Box 4220 Torshov, Nycoveien 2, N-0401. Oslo, NorwaySearch for more papers by this authorPetter-Arnt Hals MSc, Petter-Arnt Hals MSc Nycomed Imaging AS, PO Box 4220 Torshov, Nycoveien 2, N-0401, Oslo, NorwaySearch for more papers by this author Audun N. Oksendal PhD, Corresponding Author Audun N. Oksendal PhD Nycomed Imaging AS, PO Box 4220 Torshov, Nycoveien 2, N-0401, Oslo, NorwayNycomed Imaging AS, PO Box 4220 Torshov, Nycoveien 2, N-0401. Oslo, NorwaySearch for more papers by this authorPetter-Arnt Hals MSc, Petter-Arnt Hals MSc Nycomed Imaging AS, PO Box 4220 Torshov, Nycoveien 2, N-0401, Oslo, NorwaySearch for more papers by this author First published: January/February 1993 https://doi.org/10.1002/jmri.1880030128Citations: 123AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume3, Issue1Special Issue: Contrast AgentsJanuary/February 1993Pages 157-165 RelatedInformation

Iron oxides as MR imaging contrast agents.

Journal of Magnetic Resonance ImagingVolume 3, Issue 1 p. 187-194 Review Iron oxides as MR imaging contrast agents Anne K. Fahlvik PhD, Corresponding Author Anne K. Fahlvik PhD Nycomed Imaging AS, R&D Division, Nycoveien 2, P,O, Box 4220, Tor-shov, N-0401 Oslo, NorwayNycomed Imaging AS, R&D Division, Nycoveien 2, P.O. Box 4220. Tor-shov, N-0401 Oslo, NorwaySearch for more papers by this authorJo Klaveness PhD, Jo Klaveness PhD Nycomed Imaging AS, R&D Division, Nycoveien 2, P,O, Box 4220, Tor-shov, N-0401 Oslo, NorwaySearch for more papers by this authorDavid D. Stark MD, David D. Stark MD Department of Radiology, University of Massachusetts, Worcester, MassSearch for more papers by this author Anne K. Fahlvik PhD, Corresponding Author Anne K. Fahlvik PhD Nycomed Imaging AS, R&D Division, Nycoveien 2, P,O, Box 4220, Tor-shov, N-0401 Oslo, NorwayNycomed Imaging AS, R&D Division, Nycoveien 2, P.O. Box 4220. Tor-shov, N-0401 Oslo, NorwaySearch for more papers by this authorJo Klaveness PhD, Jo Klaveness PhD Nycomed Imaging AS, R&D Division, Nycoveien 2, P,O, Box 4220, Tor-shov, N-0401 Oslo, NorwaySearch for more papers by this authorDavid D. Stark MD, David D. Stark MD Department of Radiology, University of Massachusetts, Worcester, MassSearch for more papers by this author First published: January/February 1993 https://doi.org/10.1002/jmri.1880030131Citations: 45AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume3, Issue1Special Issue: Contrast AgentsJanuary/February 1993Pages 187-194 RelatedInformation