Intraindividual comparison between gadopentetate dimeglumine and gadobutrol for magnetic resonance perfusion in normal brain and intracranial tumors at 3 tesla

Abstract

Background: In vitro studies have shown that the 3-Tesla (T) magnetic resonance (MR) characteristics of high- and standard-molar gadolinium-based contrast agents differ. Such differences may indicate that high-molar (1.0 M) agents offer advantages for perfusion-weighted imaging (PWI) at 3T, as has been previously reported at 1.5T.

Purpose: To investigate possible intraindividual differences of high- versus low-molar contrast agents on PWI at 3T in patients with intracranial space-occupying lesions.

Material and Methods: Six patients with intraaxial and five patients with extraaxial tumors underwent two MR examinations at 3T, separated by at least 48 hours. On each occasion, an exogenous contrast-based, T2*-weighted, gradient-recalled echo-planar imaging (EPI) technique was used to determine the intracranial perfusion characteristics using one of two intravenous contrast agents: either 5 ml of 1.0 M gadobutrol or 10 ml of 0.5 M gadopentetate dimeglumine. The primary PWI outcome measure was region-of-interest maximal signal change (C_max).

Results: The difference in C_max for gray and white matter (ΔC_max) was significantly higher for gadobutrol compared to gadopentetate dimeglumine (P<0.01). The ratio of C_max between gray and white matter (rC_max = C_maxGray/C_maxWhite) was also significantly higher (median 24.6%, range 13.7–36.5%) for gadobutrol (P<0.01). The ratio of C_max between the whole tumor and whole normal side hemisphere was higher in five out of the six intraaxial tumor cases. A significantly higher ratio (ΔC_max/C_max) in the difference between C_max of gray and white matter (from hemisphere without brain lesion) compared to C_max for the hemisphere containing the neoplasm (hemisphere with brain lesion) was demonstrated for gadobutrol in intraaxial tumors (P<0.05).

Conclusion: Higher-concentration 1.0 M gadobutrol can offer advantages over standard 0.5 M gadopentetate dimeglumine, particularly with respect to delineation between gray and white matter and for the demarcation of highly vascularized tumor tissue on brain PWI performed at 3T.