Gadopiclenol Maintains Image Quality at a Reduced Gadolinium Dose for Intracranial Vessel and Aneurysm Wall MRI

Abstract Background Intracranial vessel wall MRI (VW-MRI) relies on gadolinium-based contrast agents (GBCAs) to assess cerebrovascular pathologies. Gadopiclenol is a high-relaxivity GBCA that may provide comparable diagnostic performance at half the gadolinium dose of conventional agents. This study compares the contrast enhancement performance of gadopiclenol with standard-dose gadobutrol for intracranial VW-MRI. Methods In this retrospective single-center study, patients with cerebral aneurysms underwent VW-MRI using either gadopiclenol (0.05 mmol/kg) or gadobutrol (0.1 mmol/kg). Qualitative image quality was independently assessed using four-point Likert scales for overall image quality, subjective noise, border delineation, and vessel wall morphology. Quantitative analyses included enhancement percentage (EP), lesion-to-background ratio (LBR), aneurysm-to-noise ratio (ANR), and normalized signal intensity (SI). Group comparisons used Wilcoxon rank-sum tests with Bonferroni correction. Mixed-effects models accounted for repeated measures and scanner variability. Inter-reader agreement was assessed using ICC and weighted Cohen's κ. Results Baseline characteristics were comparable between groups for all 53 patients and no statistically significant differences were observed between gadopiclenol (n = 26) and gadobutrol (n = 27) groups for any qualitative or quantitative metric after Bonferroni correction. A trend toward improved border delineation with gadobutrol (adjusted p = 0.094) and higher LBR with gadopiclenol (adjusted p = 0.073) did not reach statistical significance. Mixed-effects models confirmed no significant contrast-agent effect on EP ( p = 0.71) or normalized SI ( p = 0.34). Inter-reader agreement was excellent for qualitative image assessment (κ = 0.601–0.947) and good to excellent for aneurysm-specific quantitative metrics (ICC = 0.673–0.805), while background-dependent metrics demonstrated lower reproducibility. Conclusions Half-dose gadopiclenol provided image quality and enhancement metrics comparable to standard-dose gadobutrol, supporting its use for intracranial vessel wall MRI while reducing gadolinium exposure.