Case of the Day(sm)

1 of 6

Child undergoing abdominal imaging.

Our appreciation is extended to Dr. Stephen Kim,
Indiana University Department of Radiology,
for contributing this case.

History: Child undergoing abdominal imaging.

Click these images to enlarge them.

Which choice most likely characterizes the patient's clinical history?

Trauma.Lymphoma.Hemolytic anemia.Sepsis.Cystic fibrosis.

1 of 6

Case of the Day(SM) Copyright

Case of the Day(sm)

2 of 6

Child undergoing abdominal imaging.

Which of these choices is most consistent with the central enhancing focus on the image below (also shown on prior page)?

May represent a pseudoaneurysm.May represent some active extravasation.Either A or B.Neither A or B.

2 of 6

Case of the Day(SM) Copyright

Case of the Day(sm)

3 of 6

Child undergoing abdominal imaging.

Here are some ultrasound images of the same patient. Click to enlarge.

Which choice is most compatible with the ultrasound findings?

Splenic cyst.Pseudoaneurysm.Traumatic AVM.Granuloma.Splenic hemangioma.

3 of 6

Case of the Day(SM) Copyright

Case of the Day(sm)

4 of 6

Child undergoing abdominal imaging.

Findings: The CT abdomen study demonstrates a grade 4 splenic laceration and focal outpouching of an intrasplenic artery. Sonographic images of the spleen demonstrate a subcentimeter hypo echoic focus demonstrating mixed vascular flow in a “yin yang” appearance.

Diagnosis: Splenic pseudoaneurysm

4 of 6

Case of the Day(SM) Copyright

Case of the Day(sm)

5 of 6

Child undergoing abdominal imaging.

Key Points:

Pseudoaneurysm is defined as outpouching of a blood vessel, involving a defect in the 2 innermost layers (tunica intima and media) with continuity of the outermost layer (adventitia)
Grayscale ultrasound:
- Usually hypo echoic or anechoic structure
- Slow flow may occasionally be seen
- Neck connects pseudoaneurysm to artery
- String of aneurysms with multiple lumens is common
- Thrombus may be seen in the lumen
Pulsed Doppler:
- Characteristic "to and fro" flow is typically present in the neck of the aneurysm
- Turbulent high velocity flow may be present if the neck is narrowed
Color Doppler:
- Characteristic "yin-yang" sign
- Swirling flow seen as different color signals within lesion
- Lumen may not be fully filled with color due to partial thrombosis
- Flow can sometimes be detected in needle tract without an associated lumen
CT findings
- Arterial enhancement of lumen of pseudoaneurysm
- Contrast extravasation may be present if there is rupture of the pseudoaneurysm
- Fresh hematoma around pseudoaneurysm may be slightly hyper dense