Peripheral Restricted Diffusion: A Common Appearance of Hepatic Abscesses

Area of Science:

• Radiology
• Medical Imaging
• Hepatology

Background:

• Diffusion-weighted imaging (DWI) is crucial for diagnosing liver abscesses.
• The classic central diffusion restriction pattern is often considered typical for hepatic abscesses.

Purpose of the Study:

• To evaluate the frequency of the classic, central diffusion restriction pattern in hepatic abscesses compared to other patterns.
• To assess the association between diffusion restriction patterns and clinical factors.

Main Methods:

• Retrospective review of 42 hepatic abscesses.
• Three independent reviewers assessed diffusion restriction patterns (central vs. noncentral).
• Clinical data including symptom duration, organism, and leukocyte values were analyzed.

Main Results:

• Diffusion restriction patterns were variable; only 26% of lesions showed a central pattern.
• Peripheral restriction was observed in 42% of cases.
• Central diffusion restriction was associated with smaller abscess size; symptom duration was not associated with pattern.

Conclusions:

• Hepatic abscesses exhibit a more variable diffusion restriction pattern than previously recognized.
• Both central and peripheral diffusion restriction patterns are frequently observed.
• The variability in appearance necessitates caution when differentiating liver abscesses from neoplasms due to potential overlap in imaging features.