Delayed contrast enhancement of hepatic parenchyma after intravenous sonographic contrast agent: unusual phenomenon. Case report and review of literature.

Aim: A case of heterogeneous late-phase hepatic enhancement (HLHE) using contrast-enhanced ultrasound (CEUS) with SonoVue is presented, where HLHE lasted after 50 min of injection.

Methods: This study aims to review prior literature on this topic, to characterize the features of HLHE in the liver, and to find possible and reliable explanations for this phenomenon.

Results: From literature, thus far five publications discuss this phenomenon with a total of 21 patients.

Conclusion: We suggest that phagocytosis of contrast agent microbubbles by macrophages, and lymphocytosis of peripheral blood due to stress conditions of the patients might be in the background of HLHE.