A presentation about an interesting case that came to the Radiology Department of Sebha Medical Center. A 16 years old male, victim of stab wound in the lower part of the back of the right thigh, and was found to have a pseudoaneurysm in the superficial femoral artery when he was examined by ultasound one month after the injury. The presentation contains 37 slides, and is divided into the following parts : 1 - The case 2 - Pseudoaneurysms 3 - Imaging of pseudoaneurysms 4 - Treatment of pseudoaneurysms This presentation was prepared and presented by me in cooperation with D.Mabroka Ellafi in the tutorials of the Radiology Department of Sebha Medical Center.

1. Case of the week :
A case of Superficial femoral artery
Pseudoaneurysm
Dr.Abdalla Mutwakil, Dr. Mabroka Ellaffi
Radiology Department
Sebha Medical Center
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2. Presentation outline
• The case
• Pseudoaneurysms
• Imaging of pseudoaneurysms
• Treatment of pseudoaneurysms
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3. The case
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4. The case
• 16 years old male, victim of a stab wound in the back of the right thigh was
brought to the emergency department of sebha medical center one month
ago for treatment and was discharged on antibiotics and analgesia after the
stab wound was treated and dressed.
• On the 7th of April 2014, he came to the radiology department for an
Ultrasound image of the site of the stab because he was still complaining of
pain and difficulty in walking and moving the affected limb. His ultrasound
scan showed the following image :
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6. What is the Differential
diagnosis ?
• Abscess
• Hematoma
• Cyst
• Pseudoaneurysm
• True aneurysm
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7. Flow mode
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Note !
This image is taken from the web to illustrate the Ying-Yang sign in the
lesion (We missed the opprtunity store the image from our case during
examination)

8. Pseudoaneurysms
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9. Definition
• A false aneurysm (also known as a pseudoaneurysms, Pulsatile
haematoma and communicating haematoma) is when there is a breach in
the vessel wall such that blood leaks through the wall but is contained by
the adventitia or surrounding perivascular soft tissue. A direct
communication of blood flow exists between the vessel lumen and the
aneurysm lumen through the hole in the vessel wall.
• The risk of rupture is higher than that of a true aneurysm of comparable size
due to poor support of the aneurysm wall and thus false aneurysms
generally require treatment.
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11. Causes
• Trauma
• Iatrogenic
• spontaneous dissection
• Myocardial infarction
• Vasculitis
• Other causes like regional inflammatory process, Fibromuscular dysplasia
(dissection), Mycotic aneurysm (inflammatory digestion of the vessel wall)
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12. Clinical presentation
• Painful, tender, pulsatile mass (the patient may note that the pulsatile mass
is gradually expanding)
The overlying skin is sometimes erythematous (red).
• The patient may describe a history of catheterization or trauma, and they
may note that the pulsatile mass is gradually expanding.
• Because of the pain, tendernes, redness of skin a pseudoaneurysm is
sometimes confused with abscesses
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13. Location
- They can involve any arterial segment or even a cardiac chamber.
• Femoral artery pseudoaneurysm - relatively common site due to femoral
punctures
• Examples include
– Carotid artery.
– Aorta.
– Left ventricle .
– Visceral artery.
– Femoral artery.
– Peripheral arteries (limb).
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14. Carotid artery pseudoaneurysm
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15. Aortic pseudoaneurysm
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16. Left ventricular pseudoaneurysm
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17. Visceral arterial pseudoaneurysm
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18. Femoral artery pseudoaneurysm
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19. Imaging of pseudoaneurysms
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20. What are the options ?
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21. Ultrasound
- Normal USG
- Flow mode (yin-yang sign)
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22. Ultrasound
What is the yin-yang?
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23. CT
• Unenhanced CT scans may demonstrate a well define hypodense lesion
structure arising from the donor artery. Intermediate or high attenuation
(haemorrhage) adjacent to the pseudoaneurysm may been seen and
indicates pseudoaneurysmal rupture, which may vary in attenuation
dependant on being chronic or acute. The pseudoaneurysmal wall is usually
smooth and well defined except in a mycotic pseudoaneurysm, where the
wall can be thickened, irregular, or ill defined.
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24. CT
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25. Contrast enhanced CT
The patent portion of the lumen of the aneurysmal vessel demonstrates
increased attenuation, due to contrast enhancement whereas a part of the
lumen shows reduced attenuation due to a mural thrombus (yin-yang sign)
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26. CT angiography
May demonstrate a contrast filled sac. However, the entire pseudoaneurysm
however may not fill with contrast material. If a low-attenuation area remains
within the pseudoaneurysm, it usually indicates partial thrombosis . A
communication with a donor artery is adjacent to the pseudoaneurysm can
usually be seen.
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27. CT angiography

28. MRI & MRI angiography
• MR angiography can depict the pseudoaneurysm as a well-delineated
rounded structure originating from the donor artery. High-signal-intensity
thrombus may be seen within the sac on fat-suppressed T1-weighted MR
images.
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29. MRI & MRI angiography
• A 77-year-old male with a history of
dyslipidemia and hypertension was
admitted to our Emergency
Department for unstable
angina. While obtaining a complete
history, the patient reported that 20
years ago he was in a motor vehicle
accident where he suffered a severe
precordial thump but suffered no
known permanent effects.
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30. MRI & MRI angiography
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31. Angiography
• Angiography is the criterion standard to determine diagnosis and treatment.
Digital subtraction provides high-resolution imaging of small arteries and
allows percutaneous vascular intervention in the same setting. If the patient
is hemodynamically stable, performing a preoperative angiogram helps to
confirm the diagnosis. Angiography defines the character—unique or
otherwise—of the lesion and allows therapeutic planning. Angiography
greatly facilitates identification of the location and serves as a topographic
guide for the pseudoaneurysm, which aids in operative proximal and distal
control of the bleeding vessel.
• Preoperative angiography may constitute an opportunity to gain temporary
control over the bleeding vessel by performing transcatheter embolization,
thus providing a time window for the surgeon to operate on a high-risk
patient under optimum clinical conditions
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32. Angiography
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33. Treatment of pseudoaneurysms
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34. Treatment options
Many options exist for the treatment of pseudoaneurysms. While surgery was
the gold-standard treatment in the past, several less invasive treatment options
are popular today.
1 - Covered stent
2 - Ultrasound probe compression
3 - Ultrasound-guided thrombin injection
4 - Surgical ligation (with or without distal bypass)
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35. • 1 - Covered stent
– Since the pseudoaneurysm communicates with an artery through a hole in the arterial wall, a
covered stent may be placed endovascularly across this hole to "exclude it," or to prevent it from
receiving blood flow from the artery.
• 2 - Ultrasound probe compression
– Another option for treatment is ultrasound probe compression of the neck of the
pseudoaneurysm. The "neck" of the pseudoaneurysm is the narrow path of blood flow between
the artery, through the arterial wall, and into the pseudoaneurysm cavity. The artery, neck, and
pseudoaneurysm are seen on ultrasound. The ultrasound probe can be pushed firmly against the
patient's skin to compress the neck of the pseudoaneurysm for usually about 20 minutes. During
this time, the blood within the pseudoaneurysm clots; after the probe is then removed, the
pseudoaneurysm will hopefully remain clotted and will not continue to expand.
• 3 - Ultrasound-guided thrombin injection
– In addition to covered stent placement, another popular, minimally-invasive technique used today
is ultrasound-guided thrombin injection. Thrombin (factor IIa in the coagulation cascade)is a
clotting factor that converts fibrinogen into fibrin, which then polymerizes to form a blood clot.
Under ultrasound guidance, thrombin can be injected directly into a pseudoaneurysm, causing it
to clot 35

36. • 4 - Surgical ligation (with or without distal bypass)
– Open surgery may also be performed to remove pseudoaneurysms or prevent them from
expanding. If the artery is small and "expendable" - the tissues it supplies have adequate
collateral blood flow - then the artery supplying the pseudoaneurysm may be ligated both
proximally and distally to the pseudoaneurysm. The pseudoaneurysm may or may not be
removed. If the tissues supplied by the artery do not have sufficient collateral flow (the artery is
not expendable), then a vein or synthetic graft would have to be anastomosed proximally and
distally to allow for continued blood flow around the pseudoaneurysm
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