Closing the loop on internal hernias: CT of complex small bowel obstructions

Everlearning Webinar

The following cases are intended to supplement your learning experience by giving you the opportunity to review the actual images and conceptualize the three-dimensional anatomy related to the various types of obstructions presented. These cases can be reviewed before, during, and after the conference to supplement your learning.

These cases are based on an educational philosophy that promotes review of multiple variations of the same diagnosis in full case form to maximize your understanding, create a paradigm for pattern recognition, and increase your confidence when making these diagnoses independently.

Performance tips:

  • Google Chrome or safari; works well on phone and tablet with finger scrolling (pinch to zoom)

  • Consider using an external mouse with middle scroll wheel

  • If using a trackpad select the "Stack Scroll" button (it is defaulted when you open the case), click with one finger (index) and scroll with a second (middle) for a smoother, slower scroll than with two fingers alone

Round 1 : Closed-loop obstructions due to adhesions

Case 1 - adhesive band

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Case 2 - "internal hernia"

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Case 3 - hemorrhage

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Case 4 - single isolated loop

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Round 2 : Internal hernias

Case 1 - Neprectomy bed

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Case 2 - Transmesenteric

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Case 3 - Left paraduodenal

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Case 4 - Foramen of Winslow

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Challenge cases

Case 1 - CLO adhesions

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Case 2 - Petersen internal hernia

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Case 3 - CLO adhesions

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Case 4 - CLO early/late

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Supplemental : Additional key examples of internal hernias

Case 1 - Transomental

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Case 2 - "internal hernia"

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Case 3 - Right paraduodenal

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Case 4- RYGB-related

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Oral contrast for Abdominal CT

In response to questions about the use of oral contrast during the webinar, below is a simplified version of my institution's guidelines for oral contrast for CT abdomen/pelvis:


  • 800 mL flavored water with 16 mL of Iohexol

  • Additional dose on the CT table of 200 mL water + 8 mL Iohexol


  • 800 mL water with 16 mL of Iohexol in 4 doses 20-30 minutes apart


  • Oral contrast is indicated for patients with:

    • recent surgery

    • known cancer

    • suspected fistula or abscess

    • unable to get IV contrast

    • CT without oral contrast in the last 7 days

    • BMI <25

  • Practically we prefer most patients to get oral contrast in the ED setting, but the ordering provider can influence if this happens

  • We have found the biggest "bang for your buck" is "thinner" patients with a BMI <25

For additional reading:

Perry J. Pickhardt. Positive Oral Contrast Material for Abdominal CT: Current Clinical Indications and Areas of Controversy. (2020) American Journal of Roentgenology.