Chronic expanding hematoma in combination with a pseudoaneurysm: a case report.

After bleeding from trauma or surgery, most of the hematomas undergo spontaneous reabsorption. But, in some rare cases, hematomas persist for long periods as slowly expanding masses for months or years. These hematomas were termed as chronic expanding hematomas. In this report, we describe a case of chronic expanding hematoma with a pseudoaneurysm that underwent surgical biopsy, which led to an increase in its expansion speed.