Strangulated transmesenteric small bowel internal hernia

Case contributed by Dr Nolan Walker


Previous history of jejuno-ileal bypass for weight loss. Now has painful, distended abdomen with vomiting. Bowel obstruction?

Patient Data

Age: 40 years
Gender: Female

Axial and coronal CT with contrast, portal phase.

The small bowel loops are seen lateral to the right colon and also anterior to the stomach. The appearances are likely to be due to an internal hernia probably through a defect in either the
mesentery or transverse mesocolon.

Arterial supply to the small bowel appears normal.

Note the stranding within the mesentery adjacent to the malpositioned cecum, and the free fluid adjacent to this, which is suggestive of incarceration of the internal hernia.

The superior mesenteric vein is not enhancing.

This is caused by delayed venous return from the gut (venous congestion), again suggesting that the internal hernia is incarcerated and there is likely early strangulation. 

The correct position typically for jejuno-ileal anastomoses is the left upper quadrant and the fact that the anastomosis is in the right iliac fossa is concerning.

There is no small bowel dilatation. The stomach is not distended. The cecum is distended measuring 7.2 cm in maximum axial dimensions.

Note the stranding within the mesentery adjacent to the malpositioned cecum and the free fluid adjacent to this. In conjunction with the lack of enhancement of the portal vein, these findings are suggestive of incarceration of the internal hernia.



Single slice analysis of key images.

Analysis of key images.

Case Discussion

As per the operation note (see below) , the CT findings were confirmed on laparotomy.

The features on the CT demonstrate conclusively that this is an internal hernia, probably iatrogenic, secondary to the previous jejuno-ileal anastomosis.

The CT features cataloged above are all indicative of a mesenteric internal hernia which is incarcerated and has CT findings of early strangulation.

These can occur spontaneously or secondary to surgery.

Surgical operation note (abridged):

Laparoscopic converted to open reduction of internal hernia and closure of mesenteric defect


Jejuno-ileal bypass, mesenteric defect open. All of common channel, right colon and mid transverse herniated through mesenteric defect of jejuno-ileal anastomosis with evidence of venous congestion and large bowel obstruction. Free purulent fluid in pelvis.

Procedure: attempt at lap reduction of hernia not possible - decision to convert. Common channel, right colon and mid transverse reduced. All pinked up once reduced. All viable.

Mesenteric defect closed.


Case presented with:

Dr. Tony Booth FRCR

Radiology Reporting Online


Mr Marco Adamo MD

Laparoscopic Bariatric Surgeon


Ms Jihene El Kafsi FRCS

Bariatric Fellow

UCLH Bariatric Center for Weight Management and Metabolic Surgery

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Case information

rID: 50858
Published: 30th Jan 2017
Last edited: 12th Jun 2017
Inclusion in quiz mode: Included

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