Is systematic Gadolinium injection relevant during MRI follow-up for non-functioning pituitary macroadenomas?

Area of Science:

• Radiology
• Neuroimaging
• Oncology

Background:

• Non-Functioning Pituitary MacroAdenomas (NFPMAs) require regular MRI follow-up to monitor for progression.
• Contrast-enhanced T1-weighted (ceT1-w) sequences are traditionally used, but gadolinium administration has associated costs and potential risks.
• T2-weighted (T2-w) sequences offer a non-contrast alternative for imaging.

Purpose of the Study:

• To compare the diagnostic performance of coronal ceT1-w and T2-w MRI sequences for detecting progression in NFPMAs.
• To evaluate the concordance between these sequences in routine MRI follow-up.
• To assess the potential for reducing or eliminating gadolinium use in NFPMAs follow-up imaging.

Main Methods:

• Retrospective analysis of 106 patients with at least two follow-up MRIs for NFPMAs.
• Measurement of largest adenoma diameter on both coronal ceT1-w and T2-w sequences.
• Progression defined as a ≥ 2 mm diameter increase, with 3 mm and 4 mm thresholds also tested; interobserver variability assessed.

Main Results:

• High overall concordance (93.1%) between ceT1-w and T2-w sequences across 580 follow-up MRIs.
• Concordance for progression detection was 64.4% (2mm), 87.7% (3mm), and 97.1% (4mm thresholds).
• T2-w sequences showed better diagnostic performance for progression (Kappa 0.67 vs. 0.54) and 100% agreement in post-surgical resection cases.

Conclusions:

• Coronal ceT1-w and T2-w sequences demonstrate high concordance in NFPMAs follow-up, questioning the necessity of routine gadolinium administration.
• MRI without gadolinium (T2-w) can be a viable first-line option for NFPMAs monitoring.
• ceT1-w sequences may be best reserved for initial postoperative imaging and follow-up of aggressive or recurrent NFPMAs.