Ultrasound can differentiate complicated and noncomplicated acute colonic diverticulitis: a prospective comparative study with computed tomography.

OBJECTIVE: To prospectively assess the diagnostic value of intestinal ultrasound (US) compared to computerized tomography (CT) in differentiating uncomplicated and complicated acute colonic diverticulitis (ACD). MATERIALS AND METHODS: During a period of 14 months patients referred to the department of Radiology with clinical suspicion of ACD underwent an US examination. All confirmed US ACD diagnosis were included and subsequently underwent an emergency abdominal CT, used as gold standard. The WSES (World Society for Emergent Surgery) classification of diverticulitis was used. Diverticulitis was prospectively classified as either uncomplicated or complicated. Sensitivity, specificity, positive predictive value, and negative predictive values of US were evaluated. Before CT scan, the radiologist indicated whether they would have required or not a complementary CT scan, based on US findings. RESULTS: Of the 240 patients included in our study, 71 (29.6%) were Stage 0, 127 (53%) Stage 1A, and 42 (17.5%) were moderate-severe ACD (stages 1B, 2A, 2B, 3 and 4). The sensitivity of US for diagnosing complicated ACD was 84% and specificity of 95.8%. Most patients (24 of 27) misclassified by US as uncomplicated diverticulitis were classified on CT as stage 1A. From the 148 cases in which the radiologist considered CT unnecessary, only 3 of these revealed signs of complicated ACD on CT; none of them required emergency surgery. CONCLUSION: US is an effective technique to differentiate complicated from uncomplicated ACD. Our results suggest that US, may be a valuable alternative to CT for the initial radiologic evaluation in patients with clinical suspicion of ACD.

Ultrasound findings of Crohn's disease: correlation with MR enterography.

Crohn's disease is a chronic inflammatory bowel disease characterized by periods of relative inactivity alternating with acute flare-ups. Imaging techniques play a fundamental role in the diagnosis and follow-up of Crohn's disease, providing information on the extent of disease, disease activity, and the presence of extramural complications. Because of the frequent re-evaluation required by the relapsing nature of Crohn's disease and the relative young age at which most patients are diagnosed, techniques that use ionizing radiation are best avoided in monitoring this population. Thus, magnetic resonance enterography (MRE) and ultrasonography (US) are the preferable techniques. Various studies have demonstrated that US is accurate in assessing the gut. Despite some clear advantages over MRE, US has long been underused in the evaluation of intestinal disease. This review presents an overview of the main imaging findings in Crohn's disease, correlating representative US images with MRE and surgical pathology specimens. We conclude that US reliably depicts both bowel-related and mesenteric features of Crohn's disease and US findings correlate strongly with MRE findings.

Evaluation of Crohn's Disease Activity: Development of an Ultrasound Score in a Multicenter Study.

OBJECTIVE: Our goal in this multicentric prospective study was 2-fold: first, to test the diagnostic accuracy of ultrasound, color Doppler imaging (CDI), and contrast-enhanced ultrasound (CEUS) in identifying disease activity in patients with Crohn's disease (CD) compared with endoscopy as the reference standard; and, second, to construct a sonographic score that allows disease activity to be detected. MATERIALS AND METHODS: Seventy-two patients with CD from 3 hospitals underwent within a 30-day period both colonoscopy and ultrasound (US), including mural thickness, CDI, and CEUS, prospectively as part of clinical care. A multivariate analysis was carried out to assess the influence of each of the ultrasound variables in predicting endoscopic activity. We then developed a predictive ultrasound score for disease activity, and a receiver operating characteristic (ROC) curve was constructed to determine the area under the ROC curve (AUC) and the best cut-off score value to discriminate between active and inactive disease. RESULTS: Sonographic findings that were independent predictors of the presence of active disease at endoscopy were wall thickness, color grade, and contrast parameters. A score based on those variables showed high accuracy in predicting active disease, with an area under the ROC curve of 0.972. A simpler index, without contrast parameters, also showed high accuracy in detecting disease activity (AUC, 0.923). CONCLUSION: A score based on wall thickness, color Doppler grade, and contrast parameters showed high accuracy in predicting active disease. A score without including the use of contrast agent had practically similar results and is easier to use in monitoring response to treatment.

Usefulness of Ultrasound in the Diagnosis of Intestinal Anisakiasis.

OBJECTIVES: To evaluate the ultrasound (US) findings of gastrointestinal anisakiasis and the utility of US in its early diagnosis. METHODS: We retrospectively assessed the imaging findings and clinical data of 21 patients with gastrointestinal anisakiasis. Diagnosis was confirmed by a positive antigen (n = 16), endoscopy (n = 2), or a compatible clinical presentation, physical examination, and history of raw fish consumption (n = 3). Ultrasound findings reviewed included segmental circumferential bowel wall thickening, segmental edema of the valvulae conniventes, dilated small bowel loops with hyperperistalsis or hypoperistalsis, free fluid, and color Doppler hyperemia. RESULTS: Segmental circumferential bowel wall thickening was present in all 21 patients, whereas segmental edema of the valvulae conniventes was visualized in 13 patients, moderately dilated small-bowel loops proximal to the affected segment with increased peristalsis in 14 patients, small-to-moderate ascites in 18 patients, and color Doppler hyperemia in 7 patients. The US evaluation ruled out a surgical pathologic examination in all patients, and the diagnosis of anisakiasis was suggested by the radiologist on the basis of US findings in 12 patients. CONCLUSIONS: Familiarity with the suggestive US presentation of intestinal anisakiasis may allow the radiologist to propose the diagnosis of this overlooked cause of abdominal pain and may also prompt an investigation of recent raw or lightly cooked seafood ingestion. Ultrasound findings of bowel wall thickening, especially segmental edema of the valvulae conniventes, hyperperistalsis, and dilatation of small-bowel loops proximal to the affected segment, ascites, and color Doppler hyperemia, along with a history of raw fish ingestion should aid the radiologist in the diagnosis of anisakiasis.

Ultrasonographic Changes at 12 Weeks of Anti-TNF Drugs Predict 1-year Sonographic Response and Clinical Outcome in Crohn's Disease: A Multicenter Study.

BACKGROUND: The objective was to assess the long-term effect of biological treatment on transmural lesions of Crohn's disease evaluated with ultrasound, including contrast-enhanced ultrasound. METHODS: Fifty-one patients with active Crohn's disease were included in a prospective multicenter longitudinal study. All patients underwent a clinical assessment and sonographic examination at baseline, 12 weeks after treatment initiation, and after 1-year of treatment. Patients were clinically followed at least 2 years from inclusion until the end of the study. Ultrasonographic evaluation included bowel wall thickness, color Doppler grade, parietal enhancement, and presence of transmural complications or stenosis. Sonographic changes after treatment were classified as normalization, improvement, or lack of response. RESULTS: Improvement at 52 weeks was more frequent in patients with improvement at final of induction (12 weeks) compared with patients who did not improve (85% versus 28%; P < 0.0001). One-year sonographic evolution correlated with clinical response; 28 of the 29 (96.5%) patients with sonographic improvement at 52 weeks showed clinical remission or response. Patients without sonographic improvement at 52 weeks of treatment were more likely to have a change or intensification in medication or surgery (13/20, 65%) during the next year of follow-up than patients with improvement on the sonography (3/28, 11%). Stricturing behavior was the only sonographic feature associated to a negative predictive value of response (P = 0.0001). CONCLUSIONS: Sonographic response after 12 weeks of therapy is more pronounced and predicts 1-year sonographic response. Sonographic response at 1-year examination correlates with 1-year clinical response and is a predictor of further treatment's efficacy, 1-year or longer period of follow-up.

Accuracy of magnetic resonance enterography in assessing response to therapy and mucosal healing in patients with Crohn's disease.

BACKGROUND & AIMS: We assessed the accuracy of magnetic resonance enterography (MRE) in monitoring response to therapy in patients with Crohn's disease (CD) using ileocolonoscopy as a reference standard. METHODS: We performed a prospective multicenter study of 48 patients with active CD and ulcers in at least one ileocolonic segment. All patients underwent ileocolonoscopy and MRE at baseline and 12 weeks after completing treatment with corticosteroids (CS) or anti-tumor necrosis factor agents. Disease activity was quantified using Crohn's Disease Endoscopic Index of Severity (CDEIS) and Magnetic Resonance Index of Activity (MaRIA). The primary analysis was to determine the accuracy of MRE in identification of healing, defined as the disappearance of ulcers in endoscopy examination. Additional analyses established the accuracy of MRE in determining endoscopic remission (a CDEIS score <3.5) and change in severity based on consideration of all segments. RESULTS: MRE determined ulcer healing with 90% accuracy and endoscopic remission with 83% accuracy. The mean CDEIS and MaRIA scores significantly changed at week 12 in segments with ulcer healing, based on endoscopic examination (CDEIS: 21.28 ± 9.10 at baseline vs 2.73 ± 4.12 at 12 weeks; P < .001 and MaRIA: 18.86 ± 9.50 at baseline vs 8.73 ± 5.88 at 12 weeks; P < .001). The MaRIA score accurately detected changes in lesion severity (Guyatt score: 1.2 and standardized effect size: 1.07). MRE was as reliable as endoscopy in assessing healing; no significant changes in CDEIS or MaRIA scores were observed in segments with persistent ulcers, based on endoscopic examination (CDEIS: 26.43 ± 9.06 at baseline vs 20.77 ± 9.13 at 12 weeks; P = .18 and MaRIA: 22.13 ± 8.42 at baseline vs 20.77 ± 9.17 at 12 weeks; P = .42). The magnitude of change in CDEIS scores correlated with those in MaRIA scores (r = 0.51; P < .001). CONCLUSIONS: MRE evaluates ulcer healing with a high level of accuracy when ileocolonoscopy is used as the reference standard. The MaRIA is a valid, responsive, and reliable index assessing response to therapy in patients with CD.

Contrast-enhanced ultrasound in the differentiation between phlegmon and abscess in Crohn's disease and other abdominal conditions.

AIM: To evaluate the diagnostic accuracy of the contrast-enhanced ultrasound (CEUS) to differentiate between intra-abdominal phlegmon and abscess. METHODS: We retrospectively reviewed all contrast-enhanced ultrasound performed between June 2006 and May 2012 to identify patients with the terms "inflammatory mass", "phlegmon" or "abscess" on the sonographic report. The initial CEUS report was used for the diagnosis of phlegmon or abscess. RESULTS: 71 inflammatory masses in 50 patients were identified in CEUS examination. 57 masses, 21 phlegmons and 36 abscesses, were confirmed by other imaging techniques, percutaneous drainage or surgery. CEUS specificity for the diagnosis of abscess was 100%. Kappa coefficient between CEUS and other techniques in the diagnosis of phlegmon or abscess was excellent (kappa=0.972). Only in one patient surgery detected a small abscess (<2 cm) within a phlegmon that not was detected by CEUS. Statistically significant differences were found between the size of the abscesses before and after contrast agent injection. The interobserver agreement in the diagnosis of phlegmon or abscess was excellent (kappa=0.953). CONCLUSIONS: CEUS is an accurate method for differentiating between intra-abdominal phlegmon and abscess in gastrointestinal conditions, especially in CD. Its use may help to better define the size of the collections and avoid other techniques that use ionizing radiation. CEUS should be used to confirm an inflammatory mass identified at US.

Sonographic diagnosis of symptomatic ureteral calculi: usefulness of the twinkling artifact.

PURPOSE: Our aim was to analyze the value of ultrasound using the twinkling sign in the diagnosis of ureteral stones in patients with renal colic in the emergency setting. MATERIALS AND METHODS: Prospective study of 100 patients with suspected renal colic who underwent an US examination, including color Doppler mode. We analyzed sensitivity, specificity, predictive values, and accuracy. We evaluated whether the stone was observed before or after the twinkling artifact, and whether the use of the Doppler color increased the examination time. RESULTS: US including color Doppler detected 76 of the 84 confirmed lithiasis. The sensitivity and specificity were 90 % and 100 %, respectively. The positive predictive value was 100 % and the negative 67 %. The accuracy was 92 %. A total of 59 calculi (78 %) examined by color Doppler sonography showed the twinkling artifact. Seventy percent of the twinkling-positive calculi showed the artifact before the stone itself was detected. Considering the location of the stones the twinkling sign was seen before the stone in 92 % of lithiasis located in the mid lumbar ureter (p = 0.02). The use of the twinkling artifact showed a trend to facilitate the detection of smaller calculi (<10 mm) (p = 0.08). The average examination time was 5.8 min [± 4.3] (without differences between the stones detected before or after the twinkling artifact, p = 0.75). CONCLUSION: Doppler US examination shows good sensitivity and specificity for the diagnosis of symptomatic ureteral stones. The twinkling artifact is useful for the early detection of the calculi, especially in the middle tract of the ureter, usually the most difficult place in sonographic diagnosis. It also seems helpful for the detection of smaller stones. The use of color Doppler does not increase the exploration time.

Contrast-enhanced ultrasound (CEUS) in Crohn's disease: technique, image interpretation and clinical applications.

BACKGROUND: Recent meta-analysis has demonstrated no significant differences in diagnostic accuracy among different imaging techniques (US, MRI and CT) in the evaluation of Crohn's disease (CD). High-resolution bowel ultrasound has emerged as an alternative imaging technique for the diagnosis and follow-up of patients with CD, being as accurate as CT and MR for detecting intramural and extramural extension of the disease. B-Mode US can evaluate the localization and length of the affected intestinal segments and allow identification of transmural complications, stenosis and intestinal obstruction. Doppler techniques are tools that visualize and quantify bowel vascularization. Contrast-enhanced ultrasound (CEUS) is a new technique that involves IV administration of an ultrasound contrast agent with real-time examination, providing an accurate depiction of the bowel wall microvascularization and the perienteric tissues. The introduction of imaging quantification techniques enables an objective quantitative measurement of the enhancement. METHOD AND RESULTS: The article reviews the technique, sonographic findings, advantages and limitations, and clinical applications of contrast-enhanced US in the evaluation of Cohn's disease. Current CEUS applications in CD are: CD activity assessment, evaluation of inflammatory masses, distinguishing phlegmons from abscesses, characterization of stenosis by differentiating fibrosis from inflammation, monitoring the efficacy of drug treatments and improving the detection of disease recurrence. CONCLUSION: CEUS is an emerging technique that is part of the entire sonographic evaluation, with a role in the diagnosis and follow-up of CD, thus improving therapy planning and monitoring of the efficacy of treatment. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13244-011-0124-1) contains supplementary material, which is available to authorized users.

Tissue harmonic sonography in the diagnosis of common bile duct stones: a comparison with endoscopic retrograde cholangiography.

PURPOSE: To revisit the diagnostic accuracy of sonography in the detection of choledocholithiasis using modern equipment with tissue harmonic imaging (THI) and endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy as the gold standard. METHODS: A total of 107 patients with clinically suspected choledocholithiasis were examined with THI before undergoing ERCP. The sonographic findings that were prospectively evaluated included the presence of choledocholithiasis, size of common bile duct, sonographic view and patient position that best visualized the stone(s), visualization of the distal common duct, and duration of examination. The accuracy of sonography compared with ERCP and sphincterotomy was calculated. RESULTS: Sonography correctly detected stones in 65 of 76 patients (sensitivity of 86%). The specificity and the overall accuracy were 87% and 86%, respectively. The sensitivity of sonography was higher with dilated extrahepatic duct (44% in patients with common bile duct measuring less than 6 mm in diameter, 82% between 6 and 10 mm, and 100% with common bile duct larger than 10 mm). The lateral approach with the patient in left lateral decubitus position of the patient was the most effective in 47% of the cases. CONCLUSION: Sonography with THI is an accurate technique for the detection of choledocholithiasis that may be used as the first-choice technique to avoid unnecessary procedures in a high percentage of patients, especially those with dilated biliary tree.