Quantitative assessment of gadolinium deposition in dentate nucleus using quantitative susceptibility mapping

Purpose Gadolinium deposition in dentate nucleus (DN) has been reported after serial administration of gadolinium‐based contrast agents (GBCAs). Gadolinium complexes have paramagnetic properties; therefore, we evaluated susceptibility changes of gadolinium deposition in DN using quantitative susceptibility mapping (QSM) for patients after serial administration of GBCAs. Materials and Methods In all, 48 patients with brain tumors, who had had serial GBCA administrations (GBCA group), and 48 healthy volunteers without any history of GBCA administrations (non‐GBCA group) were enrolled in this study. Susceptibility values in DN on QSM and DN‐to‐cerebellum signal intensity ratios on unenhanced T 1 ‐weighted images ( T 1 ratios) on 3T were analyzed. The relationship between the number of times of GBCA administrations and susceptibility values or T 1 ratios were evaluated in the GBCA group. Results Susceptibility values at DN in the GBCA group were 0.107 ± 0.029 ppm, and significantly higher than those of the non‐GBCA group (0.079 ± 0.025 ppm) ( P < 0.0001). T 1 ratios in DN of the GBCA group were 1.059 ± 0.070, and also significantly higher than that of the non‐GBCA group (0.993 ± 0.016) ( P < 0.0001). Spearman rank correlation coefficients between susceptibility values and the number of times of linear GBCA administration showed a modest significant correlation (ρ = 0.45, P = 0.0015). There was good correlation between T 1 ratios and the number of times of linear GBCA administration, as reported previously (ρ = 0.76, P < 0.0001). Conclusion Susceptibility values on QSM in DN of the GBCA group, after serial administration of GBCAs, were significantly higher than those of the non‐GBCA group. Evidence Level: 3 J. MAGN. RESON. IMAGING 2017;45:1352–1358