Hyperintense Dentate Nuclei on T1-Weighted MRI: Relation to Repeat Gadolinium Administration

Area of Science:

• Radiology
• Neuroimaging
• Medical Physics

Background:

• Dentate nucleus hyperintensity on T1-weighted MRI is observed in various conditions.
• The exact cause of this T1 hyperintensity remains unclear.
• Potential links to radiation exposure and imaging factors are being investigated.

Purpose of the Study:

• To explore associations between dentate nucleus T1 hyperintensity and factors like contrast-enhanced MRI frequency, gadolinium dose, radiation dosage, and patient demographics.
• To determine the etiology of dentate nucleus hyperintensity in patients undergoing radiation therapy.

Main Methods:

• Retrospective review of 706 patient records from The Johns Hopkins Medical Institutions (1995-2010).
• Blind review by two readers of 184 selected patients for dentate nuclei analysis.
• Analysis of cumulative MR imaging studies, gadolinium administration, radiation dose, and patient data.

Main Results:

• 103 out of 184 patients exhibited hyperintense dentate nuclei on precontrast T1-weighted MRI.
• Significantly more gadolinium-enhanced MRI studies were performed in patients with hyperintense dentate nuclei compared to those with normal nuclei.
• No significant differences were found regarding radiation dose, serum creatinine, calcium/phosphate levels, demographics, chemotherapy history, or scanner strength.

Conclusions:

• The cumulative number of gadolinium-enhanced MRI studies is a likely contributor to persistent dentate nucleus hyperintensity on T1-weighted images.
• This finding suggests a potential link between gadolinium retention and observed T1 signal changes.
• Further research may clarify the long-term implications of these imaging findings.