Internal hernia: computed tomography diagnosis and differentiation from adhesive small bowel obstruction.
BACKGROUND
The goals of this study were to evaluate the specific computed tomography (CT) features of internal hernia (IH), and to verify CT features useful for the differential diagnosis of IH from adhesive small bowel obstruction (ASBO), and for the early detection of intestinal strangulation.


METHODS
CT findings for 28 patients with surgically proven IH were retrospectively reviewed and compared with those for 50 patients with surgically proven ASBO.


RESULTS
CT features most suggestive of IH versus ASBO included the following: a cluster of small bowel segments (100% vs 4% of patients; p < 0.0001); crowding and convergence of mesenteric vessels (79% vs 4%; p < 0.0001); mesenteric vessel engorgement (79% vs 26%; p = 0.0002); and mass effect to the surrounding bowels (82% vs 44%; p = 0.002). In addition, intestinal strangulation, the most severe complication, occurred more in IH than ASBO (39% vs 10%; p = 0.002), whereas proximal small bowel dilation (46% vs 100%; p < 0.0001) and small-bowel feces sign (0% vs 26%; p = 0.0029) were less common in IH than ASBO. The CT features indicative of intestinal strangulation were localized mesenteric fluid (p < 0.0001), mesenteric infiltrates (p = 0.0005), bowel wall thickening (p = 0.003), intramural hemorrhage (p = 0.005), mesenteric vessel engorgement (p = 0.03), and abnormal bowel wall enhancement (p = 0.008); the first 4 of these features were noted more in patients with IH than ASBO.


CONCLUSIONS
The most specific CT criteria for the diagnosis of IH, rather than ASBO, were engorged mesenteric vessels, mass effect to surrounding organs, and bowel wall thickening. When associated mesenteric infiltrates were found, intestinal strangulation was highly suspected.
Yen
Chao-Hsuan
CH
Department of Radiology Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, ROC.
Chen
Jen-Dar
JD
Tui
Chui-Mei
CM
Chou
Yi-Hong
YH
Lee
Chen-Hsen
CH
Chang
Cheng-Yen
CY
Yu
Chun
C
D000005:Abdomen / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D006547:Hernia; D006801:Humans; D007415:Intestinal Obstruction / Q000175:diagnosis* / Q000601:surgery; D007421:Intestine, Small / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D015898:Tomography Scanners, X-Ray Computed