Visceral CT findings associated with Thorotrast

Area of Science:

• Radiology
• Medical Imaging
• Hepatology

Background:

• Thorium dioxide (Thorotrast) was historically used as a contrast agent in angiography.
• Long-term retention of Thorotrast in the liver can lead to complications.
• Assessing intrahepatic Thorotrast deposits is crucial for patient monitoring.

Observation:

• Plain radiography and computed tomography (CT) were used to review four patients with prior Thorotrast angiography.
• CT scans revealed punctate Thorotrast collections in the liver parenchyma, particularly subcapsularly.
• These deposits were associated with areas of low or nonhomogeneous attenuation on CT.

Findings:

• Microscopic examination correlated low attenuation areas with hepatic fibrosis or neoplasia.
• CT imaging identified intrahepatic Thorotrast deposits with greater accuracy than plain radiography.
• The distribution of Thorotrast deposits was predominantly in the subcapsular liver zone.

Implications:

• CT is a superior imaging modality for detecting Thorotrast-induced liver changes.
• Early identification of Thorotrast deposits may aid in diagnosing associated hepatic pathologies.
• This study highlights the long-term radiological findings of Thorotrast exposure.