LIVER DAMAGE
(ULTRASOUND)
Last modified: September 23, 2025
Main reference: CAR 2020
Target population
≥ 18 years old
No previously known liver damage
See above for low vs high risk patients
Increased liver function tests alone do not increase risk
If clinical context unknown, no extrahepatic neoplasia or chronic liver disease, mention that benign-looking lesion does not require follow-up
Definitions
• Benign lesions on ultrasound
Steatosis sparing zone
Hypoechoic lesion in hyperechoic liver (steatosis)
Adjacent to the gallbladder fossa, segment IVB, porta hepatis
Geographic form without mass effect
Focal steatosis
Adjacent to the gallbladder fossa, segment IVB, porta hepatis
Geographic form
Hemangioma
< 3 cm
Homogeneous, hyperechoic, well defined
NO internal Doppler signal
Iso- or hypoechoic center with hyperechoic peripheral ring
Complex cyst:
≥ 3 septa
•Septa ≥ 3 mm thick
DDx: post-traumatic, infectious/inflammatory, neo
MRI or CT recommended
Lesion suggestive of biliary neoplasia rather than benign cyst
Dilation of the upstream bile ducts
Location in the left liver
Absence of other cysts
Important Notes
-
Stability of the lesion over 1 year in low-risk patients = benign, no further investigation
Additional Notes
-
Incidence of incidental liver injury : 10-33%
Figures
Figure 1. Original CAR 2020 Summary Recommendations for Incidental Liver Injuries on Ultrasound
References
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Bird JR, Brahm GL, Fung C, Sebastian S, Kirkpatrick IDC. Recommendations for the Management of Incidental Hepatobiliary Findings in Adults: Endorsement and Adaptation of the 2017 and 2013 ACR Incidental Findings Committee White Papers by the Canadian Association of Radiologists Incidental Findings Working Group. Can Assoc Radiol J. 2020 Nov;71(4):437-447. doi:10.1177/0846537120928349.