Which term describes a dilation of an artery that is a pulsatile hematoma due to rupture?

• A. Pseudoaneurysm
• B. Lymphocele
• C. Mycotic Aneurysm
• D. Fusiform

Answer: (A)

A pulsatile hematoma formed after a rupture that remains in communication with the artery is a pseudoaneurysm. In this scenario, blood escapes through a breach in the arterial wall and is contained by surrounding tissues, creating a sac that communicates with the arterial lumen. The wall of this dilation isn’t made of the vessel’s true layers, so it’s considered a false aneurysm. On ultrasound, you’d typically see blood flow entering and leaving the sac through a narrow neck (to-and-fro flow), a hallmark feature distinguishing it from a true aneurysm. The other options describe different entities: a lymphocele is a lymphatic fluid collection with no arterial connection; a mycotic aneurysm is an infected dilation of an artery (a true aneurysm); fusiform refers to the shape of a dilation, not the rupture with a contained hematoma.