Effect of Superparamagnetic Particles as Oral Contrast Medium at Magnetic Resonance Imaging a Phase I Clinical Study

Abstract

Non-biodegradable superparamagnetic particles were used as an oral contrast medium in different concentrations, and evaluated in 25 human volunteers. The aim of the study was to determine the most appropriate concentration of the contrast medium, and to evaluate the effect, distribution, safety and tolerance. With the concentration of 1.0 g/l a substantial reduction of the signal intensity in the bowel was achieved in both T1 and T2 weighted images. The intraabdominal structures were well differentiated from the bowels containing contrast medium. 'Metal' artifacts and bluning of adjacent structures, probably due to an increased local concentration, were observed at higher dosages. The distribution of the preparation in the gastrointestinal tract varied between individuals. As a rule a good contrast effect was achieved in the small bowel with the exception of the duodenum. The contrast medium was well accepted and did not cause any side effects of clinical importance. The results suggest that the preparation is well tolerated by humans and may be a useful contrast medium for abdominal MR imaging.

The value of hyoscine butylbromide in abdominal MR imaging with and without oral magnetic particles

“…On the basis of data from animal studies and clinical trials [4,5,11], the present investigation was approved by the Institutional Ethical Committee.…”

Contrast enhancement of the gastrointestinal tract on MR images using intravenous gadolinium-DTPA

“…Positive contrast agents leading to increased intraluminal signal intensity include ferric ammonium chloride and other paramagnetic metals [4,5], fats and oils, and orally administered gadopentetate dimeglumine [6,7]. Negative contrast agents which result in reduced intraluminal signal intensity include air and carbon dioxide effervescent granules [8], perflourooctylbromide [9,10], clays [11], and superparamagnetic iron oxide particles [12][13][14].…”

Superparamagnetische Eisenoxidpartikel: Aktueller Stand und zukünftige Entwicklungen

“…Die Transferrinrezeptor-vermittelte Aufnahme des Kontrastmittels in Tumorzellen führt zu einer starken Kontrastierung des Tumors in der Postkontrast-Aufnahme (Pfeil) (aus[97]). Magen-Darm KontrastierungIm Gegensatz zu den vorgenannten Präparationen von SPIO, die mit bioabbaubaren Materialien umhüllt sind, weisen SPIO zur Kontrastierung des Magen-Darm-Traktes eine nicht abbaubare Umhüllung auf[119]. Dies soll eine Resorption von Bestandteilen der Kontrastmittel verhindern.…”