Comparison of Ischemic and Nonischemic Bowel Segments in Patients With Mesenteric Ischemia: Multidetector Row Computed Tomography Findings and Measurement of Bowel Wall Attenuation Changes.

OBJECTIVE: To describe multidetector row computed tomography (MDCT) findings and to compare the enhancing ratio of ischemic and nonischemic bowel wall segments in patients with mesenteric ischemia. PATIENTS AND METHODS: We performed a retrospective review of 69 patients with pathologically proven mesenteric ischemia who underwent a preoperative MDCT evaluation from January 1, 2010, through December 31, 2014. Two reviewers performed quantitative MDCT measurements of the bowel wall attenuation of the ischemic and nonischemic bowel segments on the unenhanced phase, arterial phase, and portal venous phase. Receiver operating characteristic curves for the enhancing ratios on the arterial phase and portal venous phase (ERv) were calculated to discriminate the 2 segments. A concordance correlation coefficient was used to assess interobserver variability. RESULTS: The most common origin of ischemia was the mesenteric artery (45 of the 69 patients [65.2%]), but only 5 patients (7.2%) had evidence of arterial thrombus on MDCT. The quantitative MDCT measurements indicated that the ischemic bowel segments had significantly less bowel wall attenuation than the nonischemic bowel segments on the arterial phase (28.58±9.28 vs 58.97±12.50; P<.001) and the portal venous phase (33.93±11.16 vs 76.25±13.56; P<.001). The enhancing ratio on the arterial phase (cutoff, 0.32 or less; sensitivity, 89.9%; specificity, 98.6%) and the ERv (cutoff, 0.81 or less; sensitivity, 95.7%; specificity, 98.6%) predicted bowel ischemia. The most common MDCT findings in ischemic bowel were thickened bowel wall in 59 patients (85.5%), mesenteric fatty stranding in 57 (82.6%), and decreased bowel wall enhancement in 56 (81.2%). All quantitative measurements reached moderate to substantial agreement (0.399-0.601). CONCLUSION: Without oral contrast administration and at a constant 120-peak kilovolt setting, MDCT findings of decreased enhancement of the thickened bowel wall together with a low ERv value predicted the presence of an ischemic bowel segment.

Imaging differentiation of phytobezoar and small-bowel faeces: CT characteristics with quantitative analysis in patients with small- bowel obstruction.

OBJECTIVE: The objective is to use multidetector computed tomography (MDCT) to differentiate phytobezoar impaction and small-bowel faeces in patients with small-bowel obstruction (SBO). METHODS: We retrospectively reviewed 91 consecutive SBO patients with surgically proven phytobezoars (n = 31) or adhesion with small-bowel faeces (n = 60). Two readers blinded to the diagnosis recorded the following MDCT features: degree of obstruction, transition point, mesenteric fatty stranding, intraperitoneal fluid, air-fluid level, pneumatosis intestinalis, and portal venous gas. MDCT measurements of the food debris length, attenuation, luminal diameter, and wall thickness of the obstructed bowel were also compared. RESULTS: A higher grade of obstruction with an absence of mesenteric fatty stranding and intraperitoneal fluid was more commonly seen in the phytobezoar group than in the small-bowel faeces group (p < 0.01). The food debris length (phytobezoar, 5.7 ± 2.8 cm; small-bowel feces, 20.3 ± 7.9 cm, p < 0.01) and mean attenuation (phytobezoar, -59.6 ± 43.3 Hounsfield units (HU); small-bowel faeces, 8.5 ± 7.7 HU, p <0.01) were significantly different between the two groups. The ROC curve showed that food debris length <9.5 cm and mean attenuation value < -11.75 HU predicted phytobezoar impaction. CONCLUSIONS: MDCT features with measurements of the food debris length and mean attenuation assist the differentiation of phytobezoar impaction and small-bowel faeces. KEY POINTS: • MDCT examination helps to differentiate phytobezoar and small-bowel faeces. • A higher grade of obstruction is commonly associated with phytobezoar impaction. • Mesenteric fatty stranding and intraperitoneal fluid are frequently associated with small-bowel faeces. • Quantitative measurement of the obstructed bowel adds the diagnostic accuracy.

Intra-arterial calcium stimulation test with hepatic venous sampling for preoperative diagnosis of a large insulinoma in an obese young man.

Herein, we report the case of a large benign insulinoma in an obese young man with a three-year history of asymptomatic hypoglycaemia. He presented to our outpatient department with a two-week history of dizziness and morning cold sweats. A random serum glucose test revealed hypoglycaemia. Upon admission, computed tomography and magnetic resonance imaging of the abdomen with intravenous contrast media showed an enhancing mass lesion in the uncinate process of the pancreas. To confirm the diagnosis, an intra-arterial calcium stimulation test with hepatic venous sampling was performed for preoperative localisation and to exclude the presence of occult insulinomas. The patient underwent an exploratory laparotomy, with successful resection of the pancreatic head tumour. Histology confirmed the diagnosis of insulinoma. The patient's postoperative recovery was uneventful, and he has not developed further episodes of hypoglycaemia three years post surgery.

Pulmonary leiomyomas in a patient with bilateral renal cell cancer mimicking pulmonary metastases.

Pulmonary benign metastasizing leiomyoma (PBML) characterized by uterine leiomyoma in the lung is very rare. Here we report the case of a 55-year-old woman with a history of surgically resected multiple uterine leiomyomas who was histopathologically diagnosed with PBML associated with bilateral primary renal cell carcinoma (RCC). Clinicians should be aware of this unusual entity and consider pulmonary leiomyoma as a differential diagnosis in asymptomatic women with primary RCC and a history of hysterectomy for leiomyoma.