CT of Internal Hernias
Nobuyuki Takeyama, MD ; Takehiko Gokan, MD ; Yoshimitsu Ohgiya, MD ; Shuichi Satoh, MD ; Takashi Hashizume, MD ; Kiyoshi Hataya, MD ; Hiroshi Kushiro, MD ; Makoto Nakanishi, MD ; Mitsuo Kusano, MD ; Hirotsugu Munechika, MD
1 From the Departments of Radiology (N.T., T.G., Y.O., T.H., H.M.) and General and Gastrointestinal Surgery (M.K.), Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; the Departments of Radiology (S.S.) and Surgery (K.H.), Yokohama Asahi Chuo General Hospital, Yokohama, Japan; the Department of Surgery, Kikuna Memorial Hospital, Yokohama, Japan (H.K.); and the Department of Surgery, Totsuka Kyouritsu Hospital, Yokohama, Japan (M.N.). Recipient of a Certificate of Merit award for an education exhibit at the 2003 RSNA Annual Meeting. Received March 12, 2004; revision requested April 8; final revision received September 30; accepted October 5. All authors have no financial relationships to disclose.
Computed tomography (CT) plays an important role in diagnosis of acute intestinal obstruction and planning of surgical treatment. Although internal hernias are uncommon, they may be included in the differential diagnosis in cases of intestinal obstruction, especially in the absence of a history of abdominal surgery or trauma. CT findings of internal hernias include evidence of small bowel obstruction (SBO); the most common manifestation of internal hernias is strangulating SBO, which occurs after closed-loop obstruction. Therefore, in patients suspected to have internal hernias, early surgical intervention may be indicated to reduce the high morbidity and mortality rates. In a study of 13 cases of internal hernias, nine different types of internal hernias were found and the surgical and radiologic findings were correlated. The following factors may be helpful in preoperative diagnosis of internal hernias with CT: (a) knowledge of the normal anatomy of the peritoneal cavity and the characteristic anatomic location of each type of internal hernia; (b) observation of a saclike mass or cluster of dilated small bowel loops at an abnormal anatomic location in the presence of SBO; and (c) observation of an engorged, stretched, and displaced mesenteric vascular pedicle and of converging vessels at the hernial orifice.