EFFECT OF MAGNETIC-RESONANCE EXPOSURE COMBINED WITH GADOPENTETATE DIMEGLUMINE ON CHROMOSOMES IN ANIMAL SPECIMENS

Rationale and Objectives. We tested for the presence of a form of unst able chromosomal damage-anaphase bridges-that might result from the co mbined exposure to gadopentetate dimeglumine and magnetic resonance (M R) imaging in rats. Methods. Fifty-four male Sprague-Dawley rats, alon g with appropriate controls, were exposed either to MR imaging alone, gadopentetate dimeglumine alone, or a combination of the two. After ex posure, partial hepatectomies were performed to induce a vigorous mito tic response in the regenerating liver stump. Twenty-eight to 30 hr af ter partial hepatectomy, tissue specimens from regenerating liver were removed and analyzed microscopically for the presence of anaphase bri dges. Results. No anaphase bridges were detected in any of the animals , including those exposed to gadopentetate dimeglumine and MR imaging. Conclusion. Using anaphase bridge formation as an indicator. exposure to MR imaging alone, gadopentetate dimeglumine alone, or a combinatio n of the two under the conditions used in this experiment did not caus e detectable unstable chromosomal damage.