Dentate Nucleus Signal Intensity Decrease on T1-weighted MR Images after Switching from Gadopentetate Dimeglumine to...

Area of Science:

• Neuroradiology
• Magnetic Resonance Imaging (MRI)

Background:

• Repeated administration of linear gadolinium-based contrast agents (GBCAs) has been linked to increased signal intensity in the dentate nucleus.
• The long-term implications and reversibility of this phenomenon are not fully understood.

Purpose of the Study:

• To investigate whether increased dentate nucleus signal intensity, following multiple administrations of a linear GBCA (gadopentetate dimeglumine), changes after switching to a macrocyclic GBCA (gadobutrol).

Main Methods:

• Retrospective analysis of 13 patients with increased dentate nucleus signal intensity after ≥6 doses of gadopentetate dimeglumine.
• Follow-up MRI with gadobutrol (≥3 administrations) over ≥12 months.
• Measurement of dentate nucleus-to-pons and dentate nucleus-to-cerebellar peduncle signal intensity ratios, analyzed with paired t-tests and linear regression.

Main Results:

• Dentate nucleus signal intensity ratios significantly increased after gadopentetate dimeglumine (P < .0001).
• Following the switch to gadobutrol, these ratios significantly decreased (P < .0001).
• Linear regression demonstrated a significant monthly decrease in signal intensity ratios with follow-up time (P < .0001).

Conclusions:

• Increased dentate nucleus signal intensity following multiple linear GBCA administrations is reversible.
• Switching from linear to macrocyclic GBCAs leads to a reduction in dentate nucleus signal intensity over time.