Diagnostic ultrasound ( PDFDrive )

CHAPTER 12 The Retroperitoneum 441
A
B
C
FIG. 12.10 Type 1 Endoleak. (A) Color Doppler sonogram
shows blood low into the sac entering from superiorly (arrows).
Image is suspicious for a type 1 leak because the low does
not appear to enter the sac from an aortic branch. (B) Enhanced
axial computed tomography (CT) image shows the back side
of the stent graft loating off of the posterior aortic wall allowing
blood to low posterior to the stent graft into the aneurysm
sac. (C) Sagittal reformatted CT image shows contrast opaciication
of the aneurysm lumen originating from the superior aspect
of the stent graft.
Penetrating Ulcer
Penetrating ulcer has been recognized for approximately 30
years. 55 It is believed to result when an atherosclerotic ulceration
penetrates the media, allowing an intramural hematoma to form. 56
his outpouching into the media may progress, developing into
a saccular aneurysm. Penetrating ulcers occur more frequently
in the thoracic aorta but are also seen in the abdominal aorta 57,58
(Fig. 12.15).
Pseudoaneurysm
A true aneurysm is a dilation of an artery that is contained by
all three layers of the arterial wall. In contrast, a pseudoaneurysm
is a dilation that may be conined by only two layers, only one
layer, or only adjacent sot tissue. In the abdominal aorta, a
pseudoaneurysm is most likely to occur as a late surgical complication
of aortic aneurysm repair or of other arterial surgery,
almost always at sites of anastomosis. It can also be the result
of incomplete rupture of a penetrating ulcer or aneurysm
(Video 12.5). Sonographically, the appearance oten is similar
to a true aneurysm. With the proper indings, the diagnosis of
pseudoaneurysm versus true aneurysm is made largely based
on the clinical setting (e.g., previous trauma or aneurysm repair).
STENOTIC DISEASE OF THE
ABDOMINAL AORTA
Stenosis or occlusion of the abdominal aorta can be congenital
or caused by atherosclerosis, vasculitis (arteritis), trauma, or
embolus. Dissection may also result in stenosis. Midaortic
syndrome is a rare congenital stenosis that is also called abdominal
coarctation.
Symptoms of aortic stenosis or occlusion include intermittent
claudication and impotence. hese symptoms, along with the
inding of decreased femoral pulses, are called Leriche syndrome,
although the term oten is used more broadly to refer to all the