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 -weighted images (T ratios) on 3T were analyzed. The relationship between the number of times of GBCA administrations and susceptibility values or T 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 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 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.