A pseudoaneurysm is usually a rupture of the entire wall of a blood vessel after an exogenous injury, but a hematoma is formed due to the thick soft tissue surrounding the vessel and encasing the bleeding. The most significant symptom of a pseudoaneurysm is a swollen, pulsating mass localized to the hemorrhage. If the aneurysm is large, it may compress adjacent nerves and tissues and organs, creating the appropriate symptoms. If the aneurysm has an attached thrombus, it may cause a thromboembolism and result in symptoms. If a pseudoaneurysm ruptures, hemorrhage may occur, resulting in hemorrhagic shock, stroke, and other symptoms.