Accumulation of gadolinium in human cerebrospinal fluid after gadobutrol-enhanced MR imaging: A prospective observational cohort study

Purpose: To determine whether gadolinium accumulates within cerebrospinal fluid (CSF) in patients recently exposed to the macrocyclic agent gadobutrol and identify factors that may affect this accumulation. Materials and Methods: In this prospective observational cohort study, gadolinium was quantified by using inductively coupled plasma mass spectrometry of CSF samples from patients who underwent gadobutrol-enhanced magnetic resonance (MR) imaging followed by lumbar puncture within 30 days (gadobutrol group) or patients who underwent lumbar puncture without history of gadolinium-enhanced MR imaging (control group). CSF total protein level of 35 mg/dL or lower was used as a surrogate marker of an intact blood-brain barrier (BBB). Associations between gadolinium CSF concentration and patient characteristics were examined by using log (e)–linear regression models. Results: A total of 82 patients (68 in gadobutrol group, 14 in control group; 42 male and 40 female patients; median age, 47 years [interquartile range, 25–65 years]) were included in this study. Gadolinium was detected in the CSF of all 68 patients in the gadobutrol group (100% [95% confidence interval: 94.7, 100]; range, 0.2–1494 ng/mL). CSF total protein level higher than 35 mg/dL and patient age of at least 18 years were associated with higher gadolinium concentrations (estimate: 1.1, with standard error [SE] of 0.26 [P , .001] and 0.91, with SE of 0.37 [P = .02], respectively). Conclusion: Intravenous administration of the macrocyclic agent gadobutrol results in gadolinium accumulation within the CSF, even in the setting of normal renal function and no BBB dysfunction.