Gadopiclenol Versus Gadoterate Meglumine for Pediatric Brain MRI: An Intraindividual Comparison of Contrast Enhancement.

BACKGROUND. The macrocyclic agent gadopiclenol, FDA-approved in 2022, has relatively high T1 relaxivity, allowing substantial dose reductions. OBJECTIVE. The purpose of this study was to perform an intraindividual quantitative and qualitative comparison of contrast enhancement between brain MRI examinations in pediatric patients performed using gadopiclenol (0.05 mmol/kg) and gadoterate meglumine (0.1 mmol/kg). METHODS. This retrospective study included 38 pediatric patients (mean age: 11.1 years; 25 male patients, 13 female patients) who underwent gadopiclenol-enhanced brain MRI (0.05 mmol/kg) from December 1, 2024, to March 31, 2025, and gadoterate meglumine-enhanced MRI (0.1 mmol/kg) within the prior 6 months using the same field strength and protocol. Data were separately analyzed for 3D T1-weighted (T1W) fast spin-echo (FSE), 3D T1W gradient-recalled echo (GRE), and 2D FLAIR postcontrast sequences (27, 11, and 22 patients, respectively). The contrast ratio (CR) and CNR were measured in physiologic enhancing structures (choroid plexus, pituitary, dural venous sinuses, turbinate mucosa). Two neuroradiologists identified a preferred sequence for characterizing enhancement of physiologic enhancing structures (choroid plexus, pituitary, dural venous sinuses, turbinate mucosa, dura mater) in side-by-side blinded comparisons using a Likert scale (-2 to 2). RESULTS. CR was higher for gadopiclenol than for gadoterate for the choroid plexus on 3D T1W FSE images (71.0 ± 17.8 vs 63.4 ± 37.2, p = .04) and turbinate on 3D T1W GRE images (81.7 ± 21.8 vs 58.1 ± 25.2, p = .01). The remaining comparisons of CR between the two agents were not significant (p > .05). The CNR was not significantly different between the two agents for any combination of structure and sequence (p > .05). Both readers, reader 1 (R1) and reader 2 (R2), preferred gadopiclenol on 3D T1W FSE images for the choroid plexus (R1 [mean score ± SD]: -0.4 ± 0.5, p = .005; R2: -0.5 ± 0.8, p = .02) and pituitary (R1: -0.5 ± 0.7, p < .001; R2: -0.5 ± 0.9, p = .009). R2 also preferred gadopiclenol on 3D T1W FSE images for the turbinate (mean score ± SD, -0.7 ± 0.7; p < .001). Both readers preferred gadoterate meglumine on FLAIR images for the turbinate (R1: 0.3 ± 0.5, p = .01; R2: 0.5 ± 0.8, p = .02). R2 also preferred gadoterate meglumine on FLAIR images for the choroid plexus (mean score ± SD, 0.5 ± 0.8; p = .01). Neither reader had a significant preference for either agent for the remaining combinations of structure and sequence (p > .05). CONCLUSION. The findings support use of gadopiclenol at half the standard gadolinium dose for pediatric brain MRI examinations. CLINICAL IMPACT. The use of gadopiclenol could facilitate reductions in cumulative gadolinium exposure in children requiring serial MRI examinations.