Imaging description

The lateral segment of the left hepatic lobe occasionally extends laterally and wraps around the spleen, where it can be mistaken for subcapsular or perisplenic hematoma at ultrasound or CT (Figures 28.1–28.3) [1–3].

Importance

An erroneous diagnosis of subcapsular or perisplenic hematoma may result in unnecessary additional tests, procedures, or surgery [1].

Typical clinical scenario

Lateral extension of the left hepatic lobe is usually an anatomic variant, and as such may be seen incidentally in any patient. Occasionally, it may be related to compensatory left lobe hypertrophy, as in cirrhosis (Figure 28.1). From a clinical perspective, given the increasing use of ultrasound in the emergency room [4], recognition of this pitfall is particularly important in patients with blunt abdominal trauma since it is then more likely to be confused with subcapsular hematoma.

Differential diagnosis

Careful ultrasound scanning from lateral to medial or medial to lateral will show continuity between the extended lateral segment of the left hepatic lobe and the rest of the liver, preventing misinterpretation of the anatomic variant as a subcapsular hematoma. In difficult cases or if acoustic access is limited, the true nature of the finding can be easily established by contrast-enhanced CT.