Image of Thoracic Aortic Disease
2010 Guidelines on Thoracic Aortic Disease
demonstrates a high
attenuation aortic hematoma
indicating an acute aortic
Images obtained with contrast
demonstrate the contrast-
filled aortic lumen and the
hematoma as a relatively
lower attenuation band.
Traumatic aortic rupture
Traumatic injury with
pseudoaneurysm (T) in
the proximal descending
thoracic aorta, numerous
bilateral rib fractures, and
small bilateral pleural
effusions, with no
Mimic of aortic dissection created
by motion of the aortic root
Image at the level of the right
pulmonary artery demonstrates a
normal descending thoracic aorta and
pseudodissection of the ascending
aorta due to motion artifact that
occurs on non–ECG gated CT (arrow).
Image at the aortic root shows a
double contour to the aortic root that
may simulate a dissection flap (arrow).
Axial CT image demonstrates a low attenuation crescent
of material anterior to the innominate artery.
Left brachiocephalic vein mimics an
Normal anatomy of thoraco-abdominal aorta
with standard anatomic landmarks for
reporting aortic diameter as illustrated on CT
1. Aortic sinuses of Valsalva
2. Sinotubular junction
3. Mid ascending aorta (midpoint in length
between Nos. 2 and 4)
4. Proximal aortic arch (aorta at the origin
of the innominate artery)
5. Mid aortic arch (between left common
carotid and subclavian arteries)
6. Proximal descending thoracic aorta
(begins at the isthmus, approximately 2
cm distal to left subclavian artery)
7. Mid descending aorta (midpoint in
length between Nos. 6 and 8)
8. Aorta at diaphragm (2 cm above the
celiac axis origin)
9. Abdominal aorta at the celiac axis
Arch aneurysm with
Arch dissection, 2-D view
Arch dissection (arrow) with
Artifact mimicking dissection.
Top left, 2-D view.
Top right, Color-flow Doppler
Bottom, Artifact not seen in
Note narrowing of the
arterial lumen and
circumferential soft tissue
thickening of the walls of
the great vessels and
thoracic and abdominal
Panel A, Image through the
great vessels with
narrowing of the left
common carotid and left
Panel B, Mid descending
thoracic aorta (arrowheads).
Panel C, Aorta just above
Panel D, Infrarenal aorta.
Classes of intimal tears
I. Classic dissection with intimal
tear and double lumen
separated by septum.
II. Intramural hematoma. No
intimal tear or septum is imaged
but is usually found at surgery or
autopsy. DeBakey Types II and
IIIa are common extent of this
III. Intimal tear without medial
hematoma (limited dissection)
and eccentric aortic wall bulge.
Rare and difficult to detect by
TEE or CT.
IV. Penetrating atherosclerotic
ulcer usually to the adventitia
with localized hematoma or
saccular aneurysm. May
propagate to Class I dissection,
particularly when involving
ascending aorta or aortic arch.
V. Iatrogenic (catheter
angiography or intervention)/
Type A aortic dissection from
the cranial to caudal direction
Although the flap appears to
disappear in the infrarenal, it is
actually compressed against
the anterior wall of the aorta in
Panel G (arrowheads) and it is
clearly present caudally in the
common iliac arteries in Panel
H. Hemopericardium (asterisk)
is visible in Panel D. Bowel wall
indicates ischemia in Panel I.
Type A Aortic dissection
with thrombosed false
lumen and left renal artery
narrowing of the true lumen,
patent right renal artery
arising from the true lumen
(bottom left, arrow), and
narrow left renal artery
compressed by thrombus in
the false lumen, with
enhancement of the left
kidney compared with the
right kidney. *Thrombus in
Aortic dissection classification: DeBakey and Stanford Classifications
Type B aortic dissection with mediastinal hematoma and pleural blood.
Ruptured Type B aortic dissection with mediastinal hematoma (*) and pleural
blood. Left, Flap arises in the proximal descending thoracic aorta, with faint
contrast-enhanced blood adjacent to the site of rupture outside the confines of
the aortic wall (arrow).
demonstrated as a low-
attenuation band of hematoma
(arrows) in the aortic wall on
Penetrating atherosclerotic ulcer of the proximal descending thoracic aorta.
Axial CT images at the level of the aortopulmonary window (left) and at the level of
the left pulmonary artery (right) demonstrate a small penetrating ulcer (long arrow,
U) that extends beyond the expected confines of the aortic lumen with adjacent
intramural hematoma both at the level of the ulcer itself and that extends a few
centimeters caudally in the wall of the descending thoracic aorta (short arrows).
Descending aneurysms are
classified as involving
thirds of the descending
thoracic aorta and various
combinations. A involves
the proximal third, B the
middle third, and C as the
aneurysms are classified
according to the Crawford
classification: Type I
extends from proximal to
the 6th rib and extends
down to the renal arteries.
Type II extends from
proximal to the 6th rib and extends to below the renal arteries. Type III extends from
distal to the 6th rib but from above the diaphragm into the abdominal aorta. Type IV
extends from below the diaphragm and involves the entire visceral aortic segment
and most of the abdominal aorta. Juxtarenal and supraenal aneurysms are excluded.
Top left and right, PA and
lateral CXR show an anterior
mediastinal mass with
curvilinear calcifications most
likely representing the wall of
an ascending aortic aneurysm.
Bottom left, CT scan slice at
the level of the right
pulmonary artery confirms a
10-cm aneurysm of the
ascending aorta with dense
mural calcifications. Bottom
right, A maximum intensity
projection in the oblique
sagittal plane better
demonstrates the fusiform
aneurysm beginning at the
sinotubular ridge and
extending into the aortic arch.
Dense mural calcification
extends into the proximal