Radiological findings in symptomatic internal hernias after laparoscopic gastric bypass

Bariatric Surgery Emergencies in Acute Care Surgery

Patients who have undergone bariatric surgery present unique challenges in the acute care surgery setting. This review includes the presentation, workup, and management of most common bariatric surgery emergencies encountered by acute care surgery.

Chylous Ascites Pointing Toward an Internal Hernia in the Setting of Roux-en-Y Gastric Bypass: A Case Report

Chylous ascites is a rare but significant complication of a variety of surgical procedures. It is an uncommon complication of laparoscopic Roux-en-Y gastric bypass (LRGYB). The underlying etiology is assumed to be an internal hernia, in which the hernia causes lymphatic channel engorgement and lymphatic extravasation. We present the case of a 34-year-old male who had a history of LRGYB a year back and had been experiencing gradually worsening, colicky abdominal pain radiating to the right flank for the last 24 hours. Laparoscopic exploration revealed chylous ascites due to internal herniation owing to the complication of LRYGB. Classic signs of internal hernias such as mesenteric swirl were absent on the computed tomography scan of the abdomen.

The Diagnostic Accuracy of Abdominal Computed Tomography in Diagnosing Internal Herniation Following Roux-en-Y Gastric Bypass Surgery: A Systematic Review and Meta-analysis

OBJECTIVE

To analyze the diagnostic accuracy of abdominal computed tomography (CT) in diagnosing internal herniation (IH) following Rouxen-Y gastric bypass (RYGB) surgery.

SUMMARY OF BACKGROUND DATA

IH is one of the most important and challenging complications following RYGB. Therefore, early and adequate diagnosis of IH is necessary. Currently, exploratory surgery is considered the gold standard in diagnosing IH. Although CT scans are frequently being used, the true diagnostic accuracy in diagnosing IH remains unclear.

METHODS

PubMed, Embase, and Cochrane databases were systematically searched for relevant articles describing the diagnostic accuracy of abdominal CT in diagnosing IH after RYGB. Data were extracted, recalculated, and pooled to report on the overall diagnostic accuracy of CT in diagnosing IH, and the diagnostic accuracy of specific radiological signs.

RESULTS

A total of 20 studies describing 1637 patients were included. seventeen studies provided data regarding the overall diagnostic accuracy: pooled sensitivity of 82.0%, specificity of 84.8%, positive predictive value of 82.7%, and negative predictive value of 85.8% were calculated. Eleven studies reported on specific CT signs and their diagnostic accuracy. The radiological signs with the highest sensitivity were the signs of venous congestion, swirl, and mesenteric oedema (sensitivity of 78.7%, 77.8%, and 67.2%, respectively).

CONCLUSIONS

This meta-analysis demonstrates that CT is a reliable imaging modality for the detection of IH. Therefore, abdominal CT imaging should be added to the diagnostic work-up for RYGB patients who present themselves with abdominal pain suggestive of IH to improve patient selection for explorative surgery.

Imaging Postoperative Abdominal Hernias: A Review with a Clinical Perspective

Postoperative internal hernia is a challenging but critical diagnosis in postoperative patients presenting with acute abdomen. Postoperative internal hernias are increasingly being recognized after Roux-en-Y gastric bypass (RYGB) and bariatric surgeries. These internal hernias have a high risk of closed-loop obstruction and bowel ischemia; therefore, prompt recognition is necessary. Computed tomography (CT) is the imaging modality of choice in cases of postoperative acute abdomen. Understanding the types of postoperative internal hernia and their common imaging features on CT is crucial for the abdominal radiologist. Postoperative external hernias are usually a result of defect or weakness of the abdominal wall created because of the surgery. CT helps in the detection, delineation, diagnosis of complications, and surgical planning of an external hernia. In this article, the anatomy, pathophysiology, and CT features of common postoperative hernias are discussed. Afterreading this review, the readers should be able to (1) enumerate the common postoperative internal and external abdominal hernias, (2) explain the pathophysiology and surgical anatomy of Roux-en-Y gastric bypass-related hernia, (3) identify the common imaging features of postoperative hernia, and (4) diagnose the complications of postoperative hernias.

Role of CT imaging in discriminating internal hernia from aspecific abdominal pain following Roux-en-Y gastric bypass: a single high-volume centre experience

Internal hernia (IH) represents a delayed complication of the laparoscopic Roux-en-Y gastric bypass (LRYGB) and it is historically difficult to identify preoperatively. Numerous CT signs were considered suggestive of IH but none of them is pathognomonic. In this study, we aim to evaluate the accuracy of CT in diagnosing IH, differentiating from non-specific abdominal pain. This can lead to a way of personalized medicine and improve the outcome of anti-obesity treatments. We retrospectively reviewed CT scans of 50 patients previously subjected to LRYGB procedure, with a clinical suspicion of IH. 3 groups of patients were identified: IH group (21 patients with a surgical confirmed IH), negative group (12 patients in whom IH was not confirmed at surgery), and control group (17 patients who were not surgically explored because of low/no suspicion of IH). We divided CT signs into three groups: "bowel loop signs", "vessel signs", and "venous congestion/stasis signs". The accuracy of CT in detecting IH was tested by comparing each sign, either individually or in combination, with the surgical findings. Statistical analysis showed that "vessel signs" (swirl sign, superior mesenteric vein beaking, mesenteric arteries, and veins branches inversion) present the highest distribution in patients with IH demonstrated at surgery, with a higher accuracy in case of simultaneous presence of two or three signs. CT imaging is highly accurate in diagnosing IH. Despite no single sign being pathognomonic, the combination of two or more signs, especially among the "vessels signs", can suggest the IH, even in pauci-symptomatic patients.

INTERNAL HERNIA FOLLOWING LAPAROSCOPIC ROUX-EN-Y GASTRIC BY-PASS: INDICATIVE FACTORS FOR EARLY REPAIR

BACKGROUND

Internal hernia (IH) following laparoscopic Roux-en-Y gastric bypass (LRYGB) is a major complication that challenges the surgeon due to its non-specific presentation and necessity of early repair. Delayed diagnosis and surgical intervention of IH might lead to increased morbidity of patients and impairments in their quality of life.

OBJECTIVE

To evaluate the predictive factors for early diagnosis and surgical repair of IH after LRYGB.

METHODS

This study analyzed 38 patients during the postoperative period of LRYGB who presented clinical manifestations suggestive of IH after an average of 24 months following the bariatric procedure.

RESULTS

The sample consisted of 10 men and 28 women, with a mean age of 37.5 years and a mean body mass index (BMI) of 39.6 kg/m2 before LRYGB. All patients presented pain, 23 presented abdominal distension, 10 had nausea and 12 were vomiting; three of them had dysphagia, three had diarrhea and one had gastro-esophageal reflux. The patients presented symptoms for an average of 15 days, varying from 3 to 50 days. Seventeen (45.9%) patients were seen once, while the other 20 (54.1%) went to the emergency room twice or more times. Exploratory laparoscopy was performed on all patients, being converted to laparotomy in three cases. Petersen hernia was confirmed in 22 (57.9%). Petersen space was closed in all patients and the IH correction was performed in 20 (52.6%) cases. The herniated loop showed signs of vascular suffering in seven patients, and two (5.3%) had irreversible ischemia, requiring bowel resection.

CONCLUSION

The presence of recurrent abdominal pain is one of the main indicators for the diagnosis of IH after LRYGB. Patients operated at an early stage, even with negative imaging tests for this disease, benefited from rapid and simple procedures without major complications.

The diagnostic performance and interrater agreement of seven CT findings in the diagnosis of internal hernia after gastric bypass operation

PURPOSE

A reliable and immediate diagnosis of internal hernia is important for optimal and timely management of patients with a history of gastric bypass surgery. The aims of this study were to evaluate the interrater agreement and diagnostic performance characteristics of seven predefined CT findings of internal herniation in patients admitted on clinical suspicion of internal herniation after laparoscopic Roux-en-Y gastric bypass (LRYGB).

METHODS

Abdominal CT scans of 117 patients performed on clinical suspicion of internal hernia after LRYGB surgery were evaluated by three radiologists (two experts and one resident) for the following: (1) Swirl sign, (2) strangulation of superior mesenteric vein (SMV), (3) engorged mesenteric vessels and edema, (4) engorged lymph nodes, (5) ascites, (6) mushroom sign, (7) hurricane eye sign, and finally the overall conclusion. The CT findings were compared to the laparoscopic explorative findings.

RESULTS

The highest interrater agreements were seen for the swirl sign, SMV strangulation, ascites, and overall conclusion (all Kappa 0.82-0.83). The presence of internal hernia was significantly and independently associated with SMV strangulation (OR 18.3; 95% CI 4.3-78.1; p < 0.001) and mesenteric edema (OR 5.2; 95% CI 1.4-19.6; p < 0.001) on multivariate analysis, while the other CT findings were not independently associated with herniation. The highest sensitivity was observed for mesenteric edema (85.0%), while SMV strangulation had the highest specificity (94.8%).

CONCLUSION

CT is an accurate diagnostic tool for detection of internal hernia after LRYGB. SMV strangulation and mesenteric edema are highly predictive and easily identified features of internal herniation.

Laparoscopic management of an internal hernia in a pregnant woman with Roux-en-Y gastric bypass

Management of abdominal pain in a pregnant patient with a history of Roux-en-Y gastric bypass presents unique challenges. A misdiagnosis or delay in management can result in lethal maternal-fetal outcomes. We present a 30-year-old woman at 21 weeks of pregnancy presented with abdominal pain. She had a history of laparoscopic Roux-en-Y gastric bypass performed 3 years earlier. The clinical examination was remarkable for epigastric pain and tenderness. The vital signs and laboratory examinations were unremarkable. The CT scan was suggestive of an internal hernia. On an exploratory laparoscopy, the distal common small bowel was found to be herniating through the jejunojejunostomy mesenteric defect, causing intestinal obstruction with dilatation of the Roux limb and the biliopancreatic limb. The internal hernia was reduced, and no bowel resection was required. The mesenteric defect was closed with 3-0 silk sutures in a continuous fashion. The patient was discharged after 3 days and delivered a healthy baby at 40 weeks of gestation.

Mesenteric Defect Closure Decreases the Incidence of Internal Hernias Following Laparoscopic Roux-En-Y Gastric Bypass: a Retrospective Cohort Study

BACKGROUND

Laparoscopic Roux-en-Y gastric bypass (LRYGB) is one of the most effective bariatric procedures. Internal hernia (IH) is the commonest long-term complication seen after LRYGB. We analyzed the impact of closure of mesenteric defect at primary surgery on the incidence of IH. We also studied the effectiveness of pre-operative abdominal contrast-enhanced computerized tomography (CECT) in diagnosing IH.

METHODS

This is a retrospective cohort study in which we analyzed prospectively the collected data of all patients who underwent LRYGB from 2005 to 2014. All patients post-LRYGB presenting with unexplained abdominal pain with a suspicion of IH were subjected to a CECT abdomen, in which we looked specifically for "whirlpool" sign and "clustering of bowel loops." All patients underwent diagnostic laparoscopy. We compared the incidence of IH in those who did not undergo mesenteric defect closure (2005-2008, i.e., group A) with those who had the mesenteric defects closed during primary surgery (2009-2014, i.e., group B). We also calculated the sensitivity of abdominal CECT in diagnosing IH pre-operatively.

RESULTS

Among patients who did not undergo closure of any mesenteric defect (group A 2005-2009), 21/600 (3.5 %) developed IH, while 17/976 (1.7 %) patients who underwent mesenteric defect closure (group B 2009-2014) developed IH (p = 0.027). Pre-operative CECT abdomen confirmed the diagnosis of IH in 47.5 % (19/40 patients).

CONCLUSIONS

Closing of mesenteric defects after laparoscopic gastric bypass seems to be related to a lower incidence of internal hernia in the follow up. As the sensitivity of abdominal CECT is low, laparoscopic exploration is recommended based on clinical suspicion.

Internal Herniation After Laparoscopic Roux-en-Y Gastric Bypass Surgery: Pitfalls in Diagnosing and the Introduction of the AMSTERDAM Classification

INTRODUCTION

Internal herniation (IH) probably is the most elusive complication of laparoscopic Roux- en-Y gastric bypass (LRYGB) surgery. This study provides a definition for IH, a diagnosing algorithm, and information on several factors influencing IH formation.

METHOD

Baseline characteristics, laboratory findings, imaging studies, operative findings, and follow up data of 1583 patients that underwent LRYGB at our bariatric facility between 2007 and 2013 were recorded. Follow up varied between 3 and 76 months, and 85 % of the data was available for analysis at 12 months. Our surgical technique was standardized. Intermesenteric spaces were not closed until July 2012, where after they were closed. To facilitate comparison, IH cases were matched with controls.

RESULTS

Forty patients (2.5 %) had an IH during re-laparoscopy. The modal clinical presentation is acute onset epigastric discomfort, often crampy/colicky in nature. Additional examinations included laboratory testing, abdominal X-ray, abdominal ultrasound, and abdominal CT scanning. Patients who developed an IH lost a significantly higher percentage of their total body weight than their matched controls at every time point. IH incidence was higher in the non-closure group than the closure group.

CONCLUSION

The large variation in reported IH incidence is due to the large variation in IH definition. To gain more uniformity in reporting IH prevalence, we propose the use of the AMSTERDAM classification. Post-LRYGB patients with acute onset crampy/colicky epigastric pain should undergo abdominal ultrasound to rule out gallbladder pathology and offered re-laparoscopy with a low threshold. IH incidence is highest among patients with rapid weight loss and non-closure of intermesenteric defects.

Does the closure of mesenteric defects during laparoscopic gastric bypass surgery cause complications?

BACKGROUND

A well-known complication of laparoscopic Roux-en-Y gastric bypass surgery (LRYGB) is bowel obstruction due to internal herniation (IH). Evidence suggests that mesenteric defects should be closed during LRYGB to reduce the risk of IH. Therefore, surgeons are now closing mesenteric defects during LRYGB using sutures, clips, or fibrin glue. However, it has been reported that complications may arise due to the closure of mesenteric defects. The aim of this review was to summarize the reported possible complications associated with the closure of mesenteric defects during LRYGB.

METHODS

A literature search of PubMed and EMBASE was performed to identify studies related to the closure of mesenteric defects during LRYGB. The studies were screened for the listing of possible complications associated with the closure of mesenteric defects. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis recommendations.

RESULTS

Thirty studies complied with the inclusion criteria for our analysis, which included 21,789 patients. Reported complications related to closure of the mesenteric defects were: small bowel obstruction because of IH, kinking, and adhesions. IH occurred because of incomplete closure of the mesenteric defects in 1.4% of all patients, 1.2% by the antecolic approach, and 1.9% by the retrocolic approach, respectively. Kinking of the small bowel occurred in .2% of 1630 patients after closure of the mesenteric defects with clips and adhesion formation was found among 4.6% of 152 patients after closure of the mesenteric defects with nonabsorbable sutures.

CONCLUSIONS

The reported risk of complications caused by closure of the mesenteric defects during LRYGB seems low.

Roux-en-Y gastric bypass-associated bowel obstruction complicating pregnancy-an obstetrician's map to the clinical minefield

Over 80% of patients undergoing bariatric surgery are women, approximately half of whom are of reproductive age. The most common procedure in the United States is the Roux-en-Y gastric bypass. Small bowel obstruction is one of many recognized postoperative complications. For such a serious condition, this entity presents with remarkable subtlety and is easily misdiagnosed, particularly in pregnant women. The consequences of late recognition can be life-threatening to both mother and fetus. We aim to decrease preventable maternal and perinatal morbidity and mortality by revealing diagnostic and therapeutic missteps related to Roux-en-Y gastric bypass-associated small bowel obstruction.

Internal hernias in pregnant women with history of gastric bypass surgery: Case series and review of literature

INTRODUCTION

Gastric bypass surgery is the most common obesity surgery procedure in women. Decreased weight loss favors fertility and leads to pregnancy sometimes just months after surgery, raising the risk of developing gastric bypass-related complications during pregnancy, including the formation of internal hernias.

PRESENTATION OF CASE

The first patient presented at 37 weeks of gestation with abdominal pain, nausea and vomiting. X-ray revealed multiple air-fluid levels and absence of gas in colon. She underwent a cesarean section and exploratory laparotomy without complications. A Petersen's space internal hernia was found. The second patient presented at 25 weeks of gestation with abdominal pain and nausea. X-ray revealed multiple air-fluid levels and a "U-shaped" intestinal loop. She underwent exploratory laparotomy with reduction of an internal hernia also in Petersen's space.

DISCUSSION

Pregnant patients with internal hernias after gastric bypass are usually of young age and with a several-day history of abdominal pain. Surgical exploration is safe and should not be delayed. The literature review showed that maternal death (9%) and fetal death (13.6%) rates are considerably high.

CONCLUSION

The possibility of an internal hernia should always be considered in pregnant women with history of gastric bypass who present with abdominal pain, in order to prevent catastrophic outcomes such as maternal and/or fetal death.

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?

BACKGROUND

Four different types of internal hernias (IH) are known to occur after laparoscopic Roux-en-Y gastric bypass (LRYGBP) performed for morbid obesity. We evaluate multidetector row helical computed tomography (MDCT) features for their differentiation.

METHODS

From a prospectively collected database including 349 patients with LRYGBP, 34 acutely symptomatic patients (28 women, mean age 32.6), operated on for IH immediately after undergoing MDCT, were selected. Surgery confirmed 4 (11.6%) patients with transmesocolic, 10 (29.4%) with Petersen's, 15 (44.2%) with mesojejunal, and 5 (14.8%) with jejunojejunal IH. In consensus, 2 radiologists analyzed 13 MDCT features to distinguish the four types of IH. Statistical significance was calculated (p<0.05, Fisher's exact test, chi-square test).

RESULTS

MDCT features of small bowel obstruction (SBO) (n=25, 73.5%), volvulus (n=22, 64.7%), or a cluster of small bowel loops (SBL) (n=27, 79.4%) were inconsistently present and overlapped between the four IH. The following features allowed for IH differentiation: left upper quadrant clustered small bowel loops (p<0.0001) and a mesocolic hernial orifice (p=0.0003) suggested transmesocolic IH. SBL abutting onto the left abdominal wall (p=0.0021) and left abdominal shift of the superior mesenteric vessels (SMV) (p=0.0045) suggested Petersen's hernia. The SMV predominantly shifted towards the right anterior abdominal wall in mesojejunal hernia (p=0.0033). Location of the hernial orifice near the distal anastomosis (p=0.0431) and jejunojejunal suture widening (p=0.0005) indicated jejunojejunal hernia.

CONCLUSIONS

None of the four IH seems associated with a higher risk of SBO. Certain MDCT features, such as the position of clustered SBL and hernial orifice, help distinguish between the four IH and may permit straightforward surgery.

[Bariatric surgery and associated complications: radiological imaging]

Obesity is an increasing problem faced by the healthcare system. In managing obesity, bariatric surgery is becoming more important with evidence showing a reduction in long-term morbidity and mortality. There are special challenges faced by the radiology department in providing an imaging service for this population of patients, from technical requirements through to the interpretation of post-surgical images. This article provides an overview of the most frequently performed procedures, normal postoperative imaging findings and the appearance of common complications.

Imaging in bariatric surgery: service set-up, post-operative anatomy and complications

Obesity is an increasingly prevalent and costly problem faced by the healthcare system. The role of bariatric surgery in managing obesity has also increased with evidence showing a reduction in long-term morbidity and mortality. There are unique challenges faced by the radiology department in providing an imaging service for this population of patients, from technical and staffing requirements through to the interpretation of challenging post-surgical images. We describe these challenges and provide an overview of the most frequently performed procedures, normal post-operative imaging findings and the appearance of common complications.