Intrathecal Contrast-Enhanced Magnetic Resonance Imaging-Related Brain Signal Changes: Residual Gadolinium Deposition?

Abstract

There have been recent studies evaluating brain magnetic resonance imaging changes in patients with normal renal function, after intravenous administration of gadolinium-based contrast agents (GBCAs). Their findings were supported by histological evidence as well and brought a new vision concerning what needs to be learned to provide better patient care. In this report, we aim to present brain magnetic resonance imaging changes after intrathecal administration of a linear ionic agent (gadopentetate dimeglumine). We evaluated hyperintensities in the deep nuclei of the brain in 6 patients with normal renal function after intrathecal administration of a linear ionic GBCA, without other confounding intravenous GBCA administrations. For visual analysis, T1 signal hyperintensity of the globus pallidus (GP), putamen, pons, and dentate nucleus (DN) were scored on a 4-point scale. For quantitative analysis, using the unenhanced T1-weighted images oval regions of interests were placed within the DN, central pons, GP, and thalamus on different image slice positions. On visual analysis, 5 patients had T1 signal hyperintensity of the DN and GP, whereas the DN/pons signal intensity and the GP/thalamus signal intensity were found to be increased in all 6. This observation not only adds to our fund of knowledge concerning biodistribution and pharmacokinetics of those agents, but also raises the question of a possible association with the glymphatic pathway.