Efficacy of reduced-dose gadobutrol versus standard-dose gadoterate in contrast-enhanced MRI for the evaluation of diabetic foot osteomyelitis.

Abstract

BackgroundGadobutrol is a macrocyclic gadolinium-based contrast agent (GBCA) with higher relaxivity than other GBCAs, suggesting the potential for dose reduction without compromising image quality.PurposeTo evaluate whether a 30% reduced dose of gadobutrol is as effective as the standard dose of gadoterate for lesion visualization and enhancement in diabetic foot osteomyelitis.MethodsThis study included 132 patients with preoperative contrast-enhanced foot MRIs prior to amputation surgery for diabetic foot osteomyelitis from November 2020 to January 2023. Sixty-six enhanced foot MRIs with reduced dose gadobutrol (0.07 mmol/kg) and 66 MRIs with standard dose gadoterate (0.1 mmol/kg) were reviewed by two radiologists. For the primary study objective, two parameters (lesion border visualization and subjective lesion enhancement) for qualitative lesion visualization were assessed between the two agents using a noninferiority analysis. In the quantitative assessment of lesion enhancement, lesion-to-background ratio and enhancement percentage were compared between the two agents.ResultsThe mean scores for lesion border delineation and the visual degree of contrast enhancement were nearly identical between the two groups. For both readers, the lower limit of the 95% confidence interval (CI) for the difference did not drop below -0.35, which is above the noninferiority margin. Regarding quantitative analysis, no significant differences were observed in the enhancement percentage and lesion-to-background ratio between the two agents (p > 0.5).ConclusionA 30% reduced dose of gadobutrol (0.07 mmol/kg) is as effective as the standard gadoterate dose (0.1 mmol/kg) for lesion visualization in contrast-enhanced MRI of diabetic foot osteomyelitis, with similar enhancement efficacy.