Gadolinium deposition in the brain: association with various GBCAs using a generalized additive model

Objectives To determine the relationship between the number of administrations of various gadolinium-based contrast agents (GBCAs) and increased T1 signal intensity in the globus pallidus (GP) and dentate nucleus (DN). Methods This retrospective study included 122 patients who underwent double-dose GBCA-enhanced magnetic resonance imaging. Two radiologists calculated GP-to-thalamus (TH) signal intensity ratio, DN-to-pons signal intensity ratio and relative change (R change ) between the baseline and final examinations. Interobserver agreement was evaluated. The relationships between R change and several factors, including number of each GBCA administrations, were analysed using a generalized additive model. Results Six patients (4.9%) received linear GBCAs (mean 20.8 number of administration; range 15–30), 44 patients (36.1%) received macrocyclic GBCAs (mean 26.1; range 14–51) and 72 patients (59.0%) received both types of GBCAs (mean 31.5; range 12–65). Interobserver agreement was almost perfect (0.99; 95% CI: 0.99–0.99). R change (DN:pons) was associated with gadodiamide (p = 0.006) and gadopentetate dimeglumine (p