Pharmacokinetics of the MRI contrast agent gadobutrol in common marmoset monkeys (Callithrix jacchus)

Abstract

This study determined the pharmacokinetics of the contrast agent gadobutrol in marmosets by quantitative MRI to derive guidelines for neuroimaging protocols. Local concentrations of gadobutrol were determined from consecutive gradient echo-based mapping of the relaxation rate R1 on a clinical 3T MRI scanner. Half-time of renal elimination was measured after injection of a triple dose of gadobutrol (0.3mmol/kg) into the saphenous vein. A first-order single-compartment model was fitted to the measured R1 values and verified by blood analysis. Slow injection (1.5minutes) resulted in an elimination half-time of 26±4minutes. After bolus injection (15seconds), elimination was much slower (62±8minutes) with 45% larger distribution volumes. Importantly, more gadobutrol entered the cerebrospinal fluid. Slow injection and a latency of about 20minutes are recommended to avoid extravasation. Application of a triple dose of gadobutrol compensates for the fast elimination in healthy marmosets.