The first non-contrast enhanced image demonstrates an IMH or intramural hematoma. The second, contrast-enhanced, image demonstrates IMBP or intramural blood pool(s), also known as intramural branch artery psuedoaneurysm(s).

Both IMH and IMBP, along with PAU or penetrating atherosclerotic ulcer, and aortic dissection are included in the category of acute aortic syndrome.

This patient went on to endovascular stent grafting of the thoracic aorta with coverage and occlusion of the left subclavian artery, with left common carotid to subclavian bypass.

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