Usefulness of Helical CT in the Diagnosis of Strangulation in Small Bowel Obstruction

PURPOSE: We wished to evaluate the usefulness of helical CT for the diagnosis of strangulation of the dilated small bowels. MATERIALS AND METHODS: The CT scans of 31 patients with small bowel obstruction from various causes were reviewed retrospectively. Thirteen of these patients were confirmed as small bowel strangulation by surgery and pathology. Fourteen patients underwent surgery, but they had no strangulation. Three patients were reduced by using a nasogastric tube and one infant with intussusception was reduced by air reduction. The following CT findings of strangulation were evaluated: reduced bowel wall enhancement by visual assessment and measuring the HU, ascites, thickening of bowel wall, abnormal mesenteric vessel location and whirlpool appearance, and mesenteric venous engorgement. For the precise evaluation of reduced bowel wall enhancement, the HUs were measured by 1 mm2 of ROI, and the differences of HUs between the well enhanced bowel and poorly enhanced bowel were compared. RESULTS: For the diagnosis of strangulation, measurement of HU of the bowel wall could improve the sensitivity from 69% to 100%. The specificity of both methods, by visual assessment and measurement of HU, was 94%. Ascites had a sensitivity of 69% and specificity of 44%. Thickening of bowel wall had a sensitivity of 38% and specificity of 78%. Abnormal mesenteric vessel location and whirlpool appearance had a sensitivity of 38% and specificity of 83%. Mesenteric venous engorgement had a sensitivity of 31% and specificity of 72%. CONCLUSION:Measurement of HU of the bowel wall after contrast enhancement can be a useful method in the differential diagnosis between the strangulated and non-strangulated bowels in patients with small bowel obstruction.

Imaging Findings of Midgut Volvulus Associated with a Large Small-Bowel Diverticulum in an Adult Patient: Case Report

Although most patients with jejunoileal diverticulum are asymptomatic, a large, small-bowel diverticulum can be associated with midgut volvulus in an adult. We present a rare case of midgut volvulus that was associated with a large, small-bowel diverticulum in a 77-year-old woman presenting with chronic recurrent abdominal pain. The CT showed the characteristic whirl sign of twisted mesentery, the small bowel loops along the superior mesenteric artery and a large sac-like small-bowel diverticulum. A small bowel series also demonstrated a corkscrew appearance of proximal jejunum, a finding suggestive of midgut volvulus, and a large jejunal diverticulum. During the laparotomy, the small bowel was seen twisted counterclockwise 270 degree. The mesenteric root was very shortened. A 4 cm sized diverticulum was seen on the mesenteric border of jejunum, on the portion about 40 cm distal from the Treitz ligament.

US and CT Findings of Retroanastomotic Hernia after Gastrojejunostomy

PURPOSE: To review the radiologic findings of retroanastomotic hernia and to derive useful US and CT criteria to assist in the diagnosis of the condition in patients who have undergone gastrojejunostomy. MATERIALS AND METHODS: During a recent eight-year period, we encountered 11 consecutive cases of retroanastomotic hernia. Of the patients involved, nine underwent ultrasound (US), eight underwent computed tomography (CT), and in three, small bowel follow-through imaging was performed. The US and CT scans were reviewed to determine abnormal findings; surgical proof was available in all cases. RESULTS: The efferent loop was herniated through the defect created behind the anastomosis in eight cases, both the efferent and afferent loop in two cases, and the afferent loop in one case. Retroanastomotic hernia was prospectively diagnosed in ten of these eleven cases. Among the eight cases of efferent loop herniation, US and CT signs of retroanastomotic hernia included whirling of mesenteric vessels, jejunal loops and mesentery in the periumbilical abdomen (8/8); mural thickening of herniated bowel loops (6/8); dilatation of herniated bowel loops (4/8); (at US) decreased peristalsis of herniated bowel loops (3/7); and (at CT) decreased contrast enhancement of herniated bowel loops (1/5). In one case, US and CT signs of retroanastomotic hernia of the afferent loop included its dilatation and whirling of a short length behind the anastomosis. In two cases, US and CT signs of retroanastomotic hernia of both the afferent and efferent loop included findings of both afferent and efferent loop herniation. CONCLUSION: Retroanastomotic hernia is an important and underdiagnosed condition, and the US and CT findings we have described may permit its accurate diagnosis.

Bezoar Associated with Small Bowel Obstruction: Comparison of CT and US

PURPOSE: To compare the accuracy of computed tomography (CT) and ultrasound (US) in the diagnosis of bezoars in small bowel obstruction. MATERIALS AND METHODS: During a recent eight-year period, 23 patients underwent surgery due to small bowel obstruction caused by bezoars, and 14 who underwent both CT and US were included in this study. The scans obtained were retrospectively reviewed by two radiologists working independently, and the usefulness of each modality in terms of diagnostic capacity, determination of the level of obstruction and detection of additional bezoars was assessed. RESULTS: At surgery, a total of 22 bezoars were removed: 19 from the small intestine and three from the stomach; multiple bezoars were found in five of the 14 patients. The presence of bezoars was demonstrated by CT in all patients, and by US in ten (71%) (p=0.125). The level of obstruction was correctly predicted in 57% of cases at US and in 100% at CT (p=0.03). Overall sensitivity was 55% for US (12/22) and 96% for CT (21/22) (p<0.01). In three patients with associated gastric bezoars, US revealed only one, whereas all were demonstrated by CT. In five with multiple lesions, only five (39%) of 13 were apparent at US, but 12 (92%) were revealed by CT. CONCLUSION: Both US and CT were useful for the diagnosis of small bowel obstruction caused by bezoars. CT however, was more accurate in determining the level of obstruction and in revealing additional bezoars in the small bowel and stomach.

High Grade MALT Lymphoma of the Ileum in a Child Presenting as Intussusception: A Case Report

Lymphoma is the third most common childhood malignancy after leukemia and brain tumor. In contrast to adult non-Hodgkin's lymphoma, that occurring in children is usually found extranodally. The most common site is the abdomen, including the gastrointestinal tract, kidney and pancreas, and the next most common is the extranodal head and neck. Gastrointestinal non-Hodgkin's lymphoma in adults is usually considered to be MALT lymphoma, a distinct B-cell type, but the occurrence of this variety in the small bowel of children is relatively rare. We report a case of high-grade MALT lymphoma occurring in a nine-year-old boy who presented with ileoileal intussusception.

Two Case Reports of Intussusception in Patients with Peutz-Jeghers Syndrome

Peutz-Jeghers syndrome(PJS) is a relatively rare autosomal-dominant disease characterized by the occurrence of extensive mucocutaneous hyperpigmentation and gastrointestinal polyps. PJS patients are considered to have a high prevalence of intussusception due to polyps. We report the radiological findings in two cases of intussusception due to polyps in patients with PJS, and review the literature.

CT Findings of Right Paraduodenal Hernia Presenting as Acute Small Bowel Obstruction

Because it is rare, acute small bowel obstruction due to right paraduodenal hernia is an entity with which radiologists are not entirely familiar. Its clinical importance, however, lies in the fat that delayed diagnosis leads to significantly increased morbidity and mortality rates. We report a case of small bowel obstruction due to right paraduodenal hernia in which all the known characteristic findings were demonstrated.

Differential Diagnosis of Medchanical Bowel Ostruction and Paralytic Ileus on CT Features

PURPOSE: To evaluate CT findings for the differential diagnosis of mechanical bowel obstruction and paralytic ileus. MATERIALS AND METHODS: Without information relating to clinical or operative findings, we retrospectively analyzed the CT scans of 24 patients with mechanical bowel obstruction and 19 patients with paralytic ileus. Final diagnosis was confirmed by operation (n=26), or by clinical symptoms, radiologic findings and follow-up study CT findings were obtained : 1) the diameter of the most dilated part of the small bowel, and the thickness and enhancing pattern of the dilated small bowel wall; 2) the diameter of the most dilated part of the descending colon and the ratio of the diameter of the small bowel to that of the descending colon; 3) the number of transitional zones, length and thickness. and 4) associated ascites and its location. RESULTS: The mean diameters of the most dilated part of the small bowel in mechanical bowel obstruction and paralytic ileus were 3.6cm and 2.9cm, respectively. The diameter of the small bowel in mechanical bowel obstruction was significantly greater than in paralytic ileus(p< .05). The mean thickness of dilated small bowel wall was 4.0mm in mechanical bowel obstruction and 2.4mm in paralytic ielus, and target-like enhancement was prominent in mechanical bowel obstruction (46%) (p< .05). he mean diameter of the most dilated part of the descending colon was not significantly different to that of the most dilated part of the small bowel, but the ratio of the diameter of the small bowel to that of the colon was 2.9 in mechanical bowel obstruction and 1.9 in paralytic ileus, respectively, which was statistically significant (p< .05). A transitional zone was seen in 23 cases (96%) of mechanical bowel obstruction and in nine (47%) of paralytic ileus. In mechanical bowel obstruction, mean transitional zone length was 2cm, shorter than that of paralytic ileus (3.4cm) (p< .05) The thickness of transitional zone and the presence of ascites and its locations were not significantly different between mechanical bowel obstrction and paralytic ileus. CONCLUSION: In the differential diagnosis of mechanical bowel obstruction and paralytic ileus, the following CT findings were considered useful : diameter of the most dilated part of the small bowel ; thickness and target-like enhancing pattern of dilated small bowel wall ; ratio of the diameter of the small bowel to that of the descending colon ; and the number of transitional zones, and their length.

Phytobezoars in the Small Intestine: CT and US Appearances

PURPOSE: To describe CT and ultrasound(US) appearances of phytobezoar in the small intestine. MATERIALS AND METHODS: During the past two years, CT and US scans of six patients with phytobezoars of the small intestine were retrospectively reviewed. All patients presented symptoms of bowel obstruction, and four had a history of gastric surgery. Four phytobezoars were found in the jejunum and two in the ileum at surgery. We evaluated CT and US findings of phytobezoar and compared these with CT images of the removed phytobezoars. RESULTS: In three patients, US studies showed a curvilinear echogenic mass within the lumen of the dilated small bowel, with a clear posterior acoustic shadow. In six, CT scans revealed an intraluminal mass seen as having a thin soft tissue rim at the periphery and numerous aggregated low attenuation areas representing gas in the central portion. CT findings of the specimens were the same as those of phytobezoars in vivo. CONCLUSION: US and CT appearances of small intestinal phytobezoars are sufficiently distinctive to advocate the preoperative routine use of US and CT for diagnosing this entity.

CT Features for the Detection of Bowel Perforation Sites by Blunt Abdominal Trauma

PURPOSE: We evaluated the CT criteria useful for the diagnosis of the site of bowel perforation in patients with this or mesenteric injury caused by blunt abdominal trauma. MATERIALS AND METHODS: CT findings of 26patients with blunt abdominal trauma were retrospectively analyzed by two observers who were unaware of operative findings, and the results of their analysis were compared with those findings. Twenty cases of bowel perforation found at the jejunum (8), ileum (9), and colon (3), and six cases of mesenteric injuries were confirmed byoperation. We evaluated CT findings of 1) segmental bowel wall thickening, b) focal mesenteric fat infiltration, c) loculated fluid collection and d) extraluminal air adjacent to the bowel, and in addition analyzed the locations of ascites and free air, and the associated injuries of solid organs. RESULTS: The most common finding at the site of bowel perforation was segmental bowel wall thickening (17 cases), followed by focal mesenteric fatinfiltration (12 cases), loculated fluid (12 cases) and extraluminal air ajacent to the bowel (9 cases). Segmental bowel wall thickening was present at 34 sites, and the perforations were confirmed at 17 of these(50%). Focalmesenteric fat infiltration was present at 19 sites ; the perforations were proven at 12(63%). Loculated fluid collections were confirmed at 12/20 sites(60%), and extraluminal air adjacent to the bowel at 9/12(75%). Thepositive predictive value of criteria a, b, d, c) was 100%, and the positive predictive values of a, b, c) and a,d) were 60 and 67%, respectively. We observed ascites in 16 cases and intraperitoneal free air in 8 cases, the locations of ascites and free air did not, however, significantly correlate with the perforation sites. CONCLUSION: Extraluminal air adjacent to the bowel was the most specific criterion, and segmental bowel wall thickening wasthe most sensitive criterion. of all criteria, the finding 'a, b, c, d' most accurately predicted the site ofbowel perforation.

Spontaneous Perforation of Small Bowel Lymphoma Causing Massive Pneumoperitoneum: A case Report

The gastrointestinal lymphoma is a well known entity for bleeding or perforation during treatment, but spontaneous perforation is not common. We report the CT findings of an unusual case of small bowel lymphoma which presented with massive pneumoperitoneum following spontaneous perforation.