Intrahepatic splenosis: Contrast enhanced ultrasound and magnetic resonance imaging findings.

Objective: To evaluate the contrast enhanced ultrasound (CEUS) and contrast enhanced magnetic resonance imaging (CEMRI) features of intrahepatic splenosis (IHS).

Methods & materials: Five patients (three males and two females, median age, 44 years; range,32-73 years) with seven IHSs were retrieved from the database of our hospital from March 2012 to October 2021. All IHSs were confirmed histologically by surgery. The CEUS and CEMRI characteristics of individual lesion were fully analyzed.

Results: All IHS patients were asymptomatic and four out of five patients had history of splenectomy. On CEUS, all IHSs were hyperenhancement in arterial phase. 71.4% (5/7) of IHSs manifested overall filling within few seconds, the other two lesions showed centripetal filling. Subcapsular vascular hyperenhancement and feeding artery was seen in 28.6% (2/7) and 42.9% (3/7) of IHSs, respectively. During portal venous phase, IHSs presented hyperenhancement (2/7) or isoenhancement (5/7). Moreover, rim-like hypoenhanced area was uniquely observed surrounding 85.7% (6/7) of IHSs. In late phase, seven IHSs remained continuous hyper- or isoenhancement. On CEMRI, five IHSs showed mosaic hyperintense in early arterial phase, the other two lesions showed homogeneous hyperintense. In portal venous phase, all IHSs revealed continuous hyper- (71.4%, 5/7) or iso-intense (28.6%, 2/7). During late phase, one IHS (14.3%, 1/7) became hypointense, the other lesions remained hyper- or isointense.

Conclusion: Diagnosis of IHS can be based on typical CEUS and CEMRI features in patients with history of splenectomy.