MRI appearance of internal hernia following Roux-en-Y gastric bypass surgery in the pregnant patient

Abstract

In recent years, there has been a dramatic increase in the number of bariatric surgeries performed for the management of morbid obesity, 1 Lockhart M.E. Tessler F.N. Canon C.L. et al. Internal hernia after gastric bypass: sensitivity and specificity of seven CT signs with surgical correlation and controls. AJR Am J Roentgenol. 2007; 188: 745-750 Crossref PubMed Scopus (145) Google Scholar with Roux-en-Y gastric bypass (RYGB) comprising the most frequent such surgery performed in the United States. 2 Kakarla N. Dailey C. Marino T. et al. Pregnancy after gastric bypass surgery and internal hernia formation. Obstet Gynecol. 2005; 105: 1195-1198 Crossref PubMed Scopus (68) Google Scholar , 3 Efthimiou E. Stein L. Court O. et al. Internal hernia after gastric bypass surgery during middle trimester pregnancy resulting in fetal loss: risk of internal hernia never ends. Surg Obes Relat Dis. 2009; 5: 378-380 Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar A recognized complication of RYGB is the development of a transmesenteric internal hernia, in which a loop of small bowel herniates through a surgically created mesenteric defect. Although an internal hernia in this setting is challenging to diagnose clinically given the non-specific and often subtle presentation, a delay in diagnosis and operative treatment may result in dire consequences, including bowel incarceration, ischaemia, gangrene, sepsis, and possibly death. 2 Kakarla N. Dailey C. Marino T. et al. Pregnancy after gastric bypass surgery and internal hernia formation. Obstet Gynecol. 2005; 105: 1195-1198 Crossref PubMed Scopus (68) Google Scholar , 4 Naef M. Mouton W.G. Wagner H.E. Small-bowel volvulus in late pregnancy due to internal hernia after laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2009; PubMed Google Scholar , 5 Ahmed A.R. O'Malley W. Internal hernia with Roux loop obstruction during pregnancy after gastric bypass surgery. Obes Surg. 2006; 16: 1246-1248 Crossref PubMed Scopus (36) Google Scholar There has been increasing awareness by the radiology community of the risk of internal hernia following gastric bypass surgery, as well as of the critical nature of establishing the diagnosis, with numerous recent studies in the radiology literature demonstrating the ability of computed tomography (CT) to diagnose an internal hernia following RYGB. 1 Lockhart M.E. Tessler F.N. Canon C.L. et al. Internal hernia after gastric bypass: sensitivity and specificity of seven CT signs with surgical correlation and controls. AJR Am J Roentgenol. 2007; 188: 745-750 Crossref PubMed Scopus (145) Google Scholar , 6 Blachar A. Federle M.P. Dodson S.F. Internal hernia: clinical and imaging findings in 17 patients with emphasis on CT criteria. Radiology. 2001; 218: 68-74 Crossref PubMed Scopus (254) Google Scholar , 7 Martin L.C. Merkle E.M. Thompson W.M. Review of internal hernias: radiographic and clinical findings. AJR Am J Roentgenol. 2006; 186: 703-717 Crossref PubMed Scopus (317) Google Scholar , 8 Merkle E.M. Hallowell P.T. Crouse C. et al. Roux-en-Y gastric bypass for clinically severe obesity: normal appearance and spectrum of complications at imaging. Radiology. 2005; 234: 674-683 Crossref PubMed Scopus (54) Google Scholar , 9 Sandrasegaran K. Maglinte D.D. Lappas J.C. et al. Small-bowel complications of major gastrointestinal tract surgery. AJR Am J Roentgenol. 2005; 185: 671-681 Crossref PubMed Scopus (17) Google Scholar