Definition:

Focal vascular abnormality.

LI-RADS Categorization:

• Observations thought to definitely represent vascular anomalies should be categorized LR-1.
• Observations thought to probably represent vascular anomalies should be categorized LR-2.
• Observations that are indeterminate for vascular anomalies versus HCC should be categorized LR-3 or higher.

Comments:

• Most vascular anomalies are easily recognized, cause no diagnostic confusion, and do not require LI-RADS categorization. Radiologists may choose at their discretion to assign a LI-RADS category to a vascular anomaly.
• Examples of vascular anomalies that may be categorized as LR-1 or LR-2 depending on level of certainty:
• Aneurysm (CT, MR)
• Varix
• Prominent vessel along liver surface
• Cavernoma
• Arterio-portal or arterio-venous fistula
• Shunt vessel
• Vascular malformation