Imaging strategies for patients with suspicion of uncomplicated colic pain: diagnostic accuracy and management assessment.

OBJECTIVE: Compare different imaging scenarios in the diagnosis of uncomplicated renal colic due to urolithiasis (URCU). MATERIALS AND METHODS: A total of 206 prospectively included patients had been admitted with suspected URCU and had undergone abdominal plain film (APF), US and unenhanced CT after clinical STONE score evaluation. CT was the reference standard. We assessed sensitivity (Se), specificity (Spe) and Youden index for colic pain diagnosis, percentage of patients managed by urologic treatment with stone identified, percentage of alternative diagnoses (AD) and exposure to radiation, according to single imaging approaches, strategies driven by patient characteristics and conditional imaging strategies after APF and US. RESULTS: One hundred (48.5%) patients had a final diagnosis of URCU and 19 underwent urologic treatment. The conditional strategy, i.e. CT in patients who had no stone identified at US, had a perfect sensitivity and specificity. This enabled diagnosis of all stones requiring urology management while decreasing the number of CT exams by 22%. The strategy whereby CT was used when there was neither direct or indirect APF + US finding of colic pain nor alternative diagnoses in patients with a STONE score ≥ 10 had a sensitivity of 0.95 and a specificity of 0.99, identified 84% of stones managed by urologic treatment and decreased the number of CT examinations by 76%. CONCLUSION: In patients with clinical findings consistent with URCU, the use of ultrasound as first-line imaging modality, with CT restricted to patients with negative US and a STONE score ≥ 10, led to a sensitivity and specificity of above 95%, identified 84% of stones requiring urological management and reduced the number of CT scans needed by fourfold. KEY POINTS: • For diagnosis, the use of APF + US as first-line imaging, with CT restricted to patients with both a normal APF + US and a STONE score ≥ 10, provides both a sensitivity and specificity superior or equal to 95% and reduces the number of CT scans necessary by fourfold. • For management, the use of APF + US as first-line imaging, with CT restricted to patients with both a normal APF + US and a STONE score ≥ 10, maintains a 84% stone identification rate in urology-treated patients.

Assessment of Strangulation in Adhesive Small Bowel Obstruction on the Basis of Combined CT Findings: Implications for Clinical Care.

Purpose To determine which computed tomography (CT) findings or combinations of findings can help to accurately identify strangulation in adhesive small bowel obstruction (SBO). Materials and Methods Contrast agent-enhanced CT findings in a cohort of 256 patients consecutively admitted for adhesive SBO, with a delay of less than 24 hours between CT and surgery for the operated patients, were reviewed independently by two radiologists, with consensus by a third, to assess CT findings commonly associated with strangulation. The reference standard for strangulation was surgery. Univariate and multivariate analyses were performed to identify predictors of strangulation in the entire cohort and to identify predictors of the need for surgical resection in the subgroup of patients with strangulation. A CT score was obtained and diagnostic performances of different combined CT findings were calculated. Results In this study, 105 patients (41.0%; 105 of 256) underwent a surgical procedure, 62 of whom were found to have strangulation (59.0%; 62 of 105), whereas 151 patients (59.0%; 151 of 256) improved with medical care. Three CT findings were significantly associated with strangulation in the multivariate analysis: reduced bowel wall enhancement (odds ratio, 7.8; 95% confidence interval [CI]: 2.6, 23.5), diffuse mesenteric haziness (odds ratio, 6.1; 95% CI: 2.5, 15.2), and a closed-loop mechanism (odds ratio, 6.5; 95% CI: 2.8, 15.5). The model combining these three features had an area under the curve of 0.91 (95% CI: 0.86, 0.96) and a high negative predictive value (97%; 95% CI: 93%, 99%). Positive likelihood ratios were high when two or three of these CT findings were combined (positive likelihood ratios, 14.7 [95% CI: 7.1, 30.4] and 43.8 (95% CI: 14.2, 135.2], respectively). Among the strangulated cases, reduced bowel wall enhancement (odds ratio, 3.9; 95% CI: 1.3, 12) and mesenteric fluid (odds ratio, 3.6; 95% CI: 1.0, 12.8) were predictive of resection. Conclusion A score that combines three CT findings (reduced bowel wall enhancement, a closed-loop mechanism, and diffuse mesenteric haziness) can accurately predict strangulation in adhesive SBO. © RSNA, 2017 Online supplemental material is available for this article.

Value of CT to predict surgically important bowel and/or mesenteric injury in blunt trauma: performance of a preliminary scoring system.

OBJECTIVES: To evaluate the performance of a computed tomography (CT) diagnostic score to predict surgical treatment for blunt bowel and/or mesentery injury (BBMI) in consecutive abdominal trauma. METHODS: This was a retrospective observational study of 805 consecutive abdominal traumas with 556 patients included and screened by an abdominal radiologist blinded to the patient outcome, to evaluate numerous CT findings and calculate their diagnostic performances. These CT findings were compared using univariate and multivariate analysis between patients who had a laparotomy-confirmed BBMI requiring surgical repair, and those without BBMI requiring surgery. A CT score was obtained with an internal bootstrap validation. RESULTS: Fifty-six patients (10.1 %) had BBMI requiring surgery. Nine CT signs were independently associated with BBMI requiring surgery and were used to develop a CT diagnostic score. The AUC of our model was 0.98 (95 % CI 0.96-100), with a ≥5 cut-off. Its diagnostic performance was determined by internal validation: sensitivity 91.1-100 %, specificity 85.7-97.6 %, positive predictive value 41.4-82.3 % and negative predictive value 98.9-100 %. Bowel wall discontinuity and mesenteric pneumoperitoneum had the strongest association with BBMI requiring surgery (OR = 128.9 and 140.5, respectively). CONCLUSION: We developed a reliable CT scoring system which is easy to implement and highly predictive of BBMI requiring surgery. KEY POINTS: • Finding of bowel wall discontinuity or mesenteric pneumoperitoneum indicates BBMI requiring surgery. • Arterial mesenteric vessel extravasation requires surgery when in association with other CT findings. • Our CT scoring system has excellent diagnostic performance in predicting BBMI requiring surgery.