Friday, 26 September 2014

What is the name of this imaging sign?

This coronal CT image is of a young person stabbed in the left lower abdomen. What is the name given to this imaging sign?

This is the corresponding axial image:

This is known as a pear bladder. The description refers to the shape that the bladder takes when it is compressed from the sides - with the commonest reason being a pelvic haematoma secondary to injury. In this instance there is a large left sided extraperitoneal haematoma compressing the bladder. Other causes include pelvic lipomatosis.

A MIP image derived from the CT dataset shows the pear shaped bladder even more clearly:

Alexander Lucas 10.10.10" by Kombucha - Own work (Original text: eigene). Licensed under Creative Commons Attribution-Share Alike 3.0-2.5-2.0-1.0 via Wikimedia Commons -

These CT images were obtained in a delayed phase - infact 20 minutes after contrast administration. This has allowed enough time for the contrast to be excreted via the kidneys into the ureters and urinary bladder. This phase was acquired to check for ureteric or bladder injury. There is no such injury here, just a venous bleed into the pelvis.

Finally, this rotating movie shows once again the pear shaped bladder:

Dr Vikas Shah
Consultant Radiologist