Hepatic arterial pseudoaneurysm after percutaneous radiofrequency ablation for hepatocellular carcinoma

Complications of radiofrequency (RF) ablation for hepatic tumor can be categorized into the direct mechanical injury caused by an electrode and the collateral thermal damage. We experienced two cases of hepatic arterial pseudoaneurysm after percutaneous RF ablation for hepatocellular carcinoma. In the first case, direct mechanical injury to the hepatic artery by a RF electrode was considered responsible for the complications, and this was likely coupled with additional thermal injury. The patient was successfully treated with percutaneous transarterial embolization. The complications of the second case were deemed to be caused by diffuse thermal injury only. Although this type of complication is rare, we should keep it in mind because it is potentially fatal.