RESUMO
Purpose To determine whether multiple doses of gadobutrol increase the T1 signal intensity in the brains of children. Materials and Methods This retrospective imaging study evaluated 91 children (median age, 5.4 years; age range, 0-17 years) with brain tumors who underwent five or more MR brain examinations at a single institution. A subgroup of 46 patients received five or more administrations of gadobutrol (0.1 mmol/kg) and underwent follow-up MRI. T1 signal intensity in the globus pallidus and dentate nucleus was measured at the first to sixth unenhanced MR brain examination in these children. Globus pallidus-to-corpus callosum and dentate nucleus-to-corpus callosum signal intensity ratios were analyzed by linear mixed-effect analysis. Subgroup analysis was performed for six children who underwent 14 or more administrations of gadobutrol. Results The globus pallidus-to-corpus callosum ratio increased with patient age (absolute change, 0.0052 per year; 95% confidence interval: 0.0033, 0.0071; P < .0001). There was no change in the dentate nucleus-to-corpus callosum ratio with age (P = .30). Among 46 children who received five or more doses of gadobutrol (median dose, 11 mL; range, 3.9-31 mL), there was no change in signal intensity ratio of the globus pallidus (P = .17) or dentate nucleus (P = .44). Among six children who underwent more than 14 administrations of gadobutrol (median dose, 64 mL; range, 40-91 mL) there was no change in signal intensity ratio of the globus pallidus (P = .15) or dentate nucleus (P = .50). Conclusion No increase in T1-weighted signal intensity ratio was observed in the globus pallidus or dentate nucleus after the administration of at least five doses of gadobutrol. © RSNA, 2018 Online supplemental material is available for this article.