· Hematoma then forms within the media of the aortic wall
· Occurs in the elderly who usually have a history of severe atherosclerosis, hypertension, and hyperlipidemia
· Similar presentation to those with a descending thoracic aortic dissection i.e. acute chest or back pain
· Plaque ulceration usually in the middle to distal third of the descending aorta
· Intramural hematoma accompanies the penetrating ulcer 80% of the time
· Associated with abdominal aortic aneurysm
· Disease progresses from intimal plaque ulceration to media hematoma formation to adventitial saccular pseudoaneurysm formation and finally rupture if there is transmural penetration
· Speculated as the cause of descending or thrombosed type dissections with all three
Imaging findings:
· Focal contrast collection projecting beyond the aortic lumen on CT
* Intramural hematoma is indistinguishable from intraluminal thrombus
Enhanced CT scan through the lower thoracic aorta demonstratesa focal outpouching of contrast posteriorly representing a penetrating aortic ulcer
· Intimal flap is uncommon
· Intramural wall thickening or thrombus is frequently found
· On angiography, there is aortic wall thickening and the ulcerated plaque seen
· On MRI
* High signal intensity on both T1 and T2 with subacute hematoma
· Can be demonstrated by computed tomography, magnetic resonance, angiography and trans-esophageal echocardiography
· Differential diagnosis:
o Aortic dissection (has an intimal flap)
o Atheroma – has a low signal on both T1 and T2
Treatment:
· Surgical cases are those demonstrating hematoma expansion, impending rupture, inability to control blood pressure
· Patients routinely have co-morbid conditions that make them poor surgical candidates and are treated with transluminal placement of endovascular stent grafts
