Diagnosis of Transmesocolic Internal Hernia as a Complication of Retrocolic Gastric Bypass: CT Imaging Criteria

Abstract

Use of four CT signs should give radiologists a high degree of accuracy and confidence in recognizing internal hernia in patients who have undergone gastric bypass surgery.

The Four Different Types of Internal Hernia Occurring After Laparascopic Roux-en-Y Gastric Bypass Performed for Morbid Obesity: Are There Any Multidetector Computed Tomography (MDCT) Features Permitting Their Distinction?

“…The transition point always lies proximal to the jejunojejunostomy, being typically situated at the level of the mesocolic window, nicely appreciated in the sagittal plane (Fig. 4c) [2,3,7,10,20,21]. Some authors consider it the most common type of the four IH after LRYGBP [4,7,8,17,20,23], while in our series, it was the least frequent one, although the majority of our patients had a retrocolic Roux limb.…”

“…The various forms of bariatric surgery include volume restriction (vertical banding), interventions causing malabsorption (jejunoileal bypass), and procedures that combine both, namely Roux-en-Y gastric bypass (RYGBP) [1,2]. RYGBP has been shown to be the most effective technique with a reported weight loss of 60-70% over a period of 10 years follow-up [3,4].…”

“…MDCT is able to demonstrate intraluminal (bleeding, intussusception) and extraluminal (fluid collections, abscesses) intestinal complications, as well as to point out potential IH. MDCT features of these four IH have only sporadically been described, consisting of small series with potentially redundant radiological signs from one type of IH to another [2,10,[19][20][21]. The distinction between the individual types by means of MDCT has not yet been attempted.…”

Radiological imaging of the GI tract after bariatric surgery

“…3). 2,7,12,22 Although CT features have been described to aid differentiation between these various types of internal herniations, 20,22 their usefulness remains limited. The main roles of imaging are to establish the presence of obstruction, ascertain whether it is due to internal herniation, and exclude complications such as ischemia and perforation.…”

Endoscopy after bariatric surgery (with videos)

“…12,13 Many surgeons use a retrocolic technique with the Roux limb passing through the mesocolon, which may eventually lead to stenosis, bowel obstruction, or internal hernia. [14][15][16] In other cases, the length of the Roux limb may vary, some being shorter (45-60 cm) and some being longer (O150 cm). Even the type of stapler used (circular or linear) is an independent predictor of the development of a gastrojejunal stricture.…”