Aortic dissection without intimal rupture: diagnosis with MR imaging and CT

Area of Science:

• Cardiovascular Imaging
• Vascular Surgery
• Diagnostic Radiology

Background:

• Aortic dissection is a serious condition often associated with intimal tears.
• The precise etiology and imaging characteristics of aortic dissection without intimal rupture require further elucidation.

Purpose of the Study:

• To investigate the imaging findings and natural history of aortic dissection presenting without intimal rupture.
• To correlate imaging findings with pathological evidence in cases of suspected intramural hemorrhage.

Main Methods:

• Retrospective analysis of fourteen patients with suspected aortic dissection without intimal rupture.
• Utilized magnetic resonance (MR) imaging and computed tomography (CT) for diagnosis.
• Correlated imaging findings with autopsy results in two cases.

Main Results:

• MR imaging revealed a marginal high-intensity area along the aortic wall.
• CT demonstrated a nonopacified crescentic area adjacent to the aortic wall.
• These abnormalities showed a decrease in size over time, normalizing within one year.
• Autopsies confirmed intramural hemorrhage without intimal tears.

Conclusions:

• Aortic dissection can arise from intramural hemorrhage due to vasa vasorum rupture, independent of intimal tears.
• Imaging findings of intramural hematoma are distinct and resolve over time.
• This entity represents a specific form of aortic dissection.