Ultrasonic patterns in inflammatory bowel disease

Differentiation of Crohn's disease and ulcerative colitis using intestinal wall thickness of the colon: A Diagnostic accuracy study of endoscopic ultrasonography

Background: The differentiation between Ulcerative Colitis (UC) and Crohn's Disease (CD) is an important issue for choosing the appropriate treatment. Endoscopic Ultrasonography (EUS) has been used to distinguish different layers of the gastrointestinal wall. We performed this study to evaluate the accuracy of EUS in differentiating colonic UC from CD compared to standard tests (colonoscopy, pathology, imaging, and clinical presentation). Methods: This is a prospective, single-blinded diagnostic accuracy study, on 70 patients (30 UC, 30 CD, and 10 healthy controls). After obtaining informed consent, patients underwent a complete workup and were referred to an endosonographist who was blind to the diagnosis. The thickness of mucosa, submucosa and the total wall (TWT) of mid-sigmoid colon were measured by Pentax radial echoendoscope EPKI-7000 with Avius Hitachi ultrasound system (Japan). Statistical analyses were performed using the SPSS statistical software (v23). Statistical significance was considered if P-values were less than 0.05. Results: Our study revealed a sensitivity of 100% (90.7-100%) and specificity of 90.9% (70.8-98.8%) for EUS to differentiate UC and CD compared to standard diagnostic tests. Mean mucosal thickness in patients with UC was significantly greater than patients with CD, while, the mean sub-mucosal thickness was significantly greater in patients with CD (p<0.001). The sensitivity and specificity of mean mucosal thickness for differentiating UC from CD and controls were 92.3% and 88.6% with a cut-off point of 1.1 mm (p<0.001). Moreover, sensitivity and specificity of mean submucosal thickness for differentiating CD from UC and controls were 100% and 86.1% with a cut-off point of 1.08 mm (p<0.001). Conclusion: EUS can be used as an efficient modality with acceptable accuracy to differentiate Crohn's disease and Ulcerative Colitis and to determine disease activity.

Graded compression and power Doppler ultrasonography versus endoscopy to assess paediatric Crohn disease activity pre- and posttreatment

OBJECTIVE

The aim of this study was to assess whether power Doppler ultrasound (PDU) can serve as a reliable replacement for endoscopy in follow-up assessment of disease activity in children with Crohn disease.

METHODS

Nineteen children (13 boys), median age 14.8 (5.4-15.8) years, with macroscopically diagnosed Crohn disease were included in the study. Clinical parameters, histological evaluation, and graded PDU assessments were undertaken in all patients at diagnosis and following their initial treatment. Discriminant analysis was used to build predictive models from the PDU data for the histological evaluation.

RESULTS

The median Pediatric Crohn's Disease Activity Index (PCDAI) was 31.5 (15.5-42.0) at diagnosis. All clinical and ultrasonographic parameters and the histological evaluation showed an improvement between pre- versus posttreatment results; 1-way analysis of variance showed a significant difference because of treatment (P < 0.005) for all variables apart from the superior mesenteric artery flow (SMA); paired sample t tests indicated that these differences were statistically significant (P < 0.001), with the exception of SMA (P = 0.178). There was a statistically significant correlation (P < 0.001) between the platelet count and the bowel wall stratification (STRAT). Significant correlation was also observed between the histology findings and the mean mucosal, transmural, and segmental flow (MFL) and STRAT and between platelets and both MFL and small bowel thickening (SBT) (P < 0.01 in all cases). There was a statistically significant correlation (P < 0.05) between C-reactive protein and MFL and between histology and SBT, MFL, and STRAT. Discriminant analysis using discriminating factors SBT, STRAT, and MFL could assign 84.6% of cases to the correct classification of "no/mild inflammation" or "medium/severe inflammation."

CONCLUSIONS

Results obtained using power Doppler ultrasonography and endoscopy showed statistically significant correlations. Power Doppler sonography, in the hands of an experienced examiner, can be used for follow-up assessment of disease activity in children with Crohn disease.

Is the routine abdominal ultrasound a sufficiently sensitive method for the detection of colonic malignancy?

OBJECTIVE

This study examined the sensitivity of routine abdominal ultrasound scanning in the detection of colonic malignancy.

PATIENTS AND METHODS

A case control prospective study included 101 patients hospitalized at the Department of Gastroenterology and Liver Diseases of Zemun Clinical Hospital over a four-year period. Since the complaints pointed to colonic malignancy, the patients underwent routine golden standard diagnostic procedures. These patients were referred to an experienced abdominal ultrasound operator who searched for some characteristic signs of colonic malignancy. All of the participants were surgically treated after the completion of relevant procedures for diagnosing colonic malignancy. SPSS for Windows 10.0 was used for data analysis.

RESULTS

The sensitivity of an abdominal ultrasound scan in the detection and location of pathological changes pointed to colonic malignancy was different- 76% and 84% respectively. This method was very reliable in detecting right-sided colonic carcinoma (100%). Some specific ultrasonographic signs of colonic carcinoma were observed at the advanced stages of disease.

CONCLUSIONS

The routine abdominal ultrasonography can be used for the screening of colonic malignancy owing to its high sensitivity, particularly in advanced disease, but solely in conjunction with other methods. Finally, abdominal ultrasonography cannot be a definitive diagnostic tool for colonic carcinoma.

Role of US in detection of Crohn disease: meta-analysis

PURPOSE

To evaluate the accuracy of ultrasonography (US) in the detection of Crohn disease in adults by systematically reviewing both cohort studies (those including patients whose clinical characteristics were consistent with those caused by an inflammatory bowel disease) and case-control studies (those in which patients with Crohn disease were compared with patients with other bowel diseases or healthy control subjects).

MATERIALS AND METHODS

The MEDLINE, EMBASE, and Cochrane Library databases were used to retrieve all the cross-sectional studies that assessed the diagnostic accuracy of US against that of one of several predefined reference standards (ie, radiologic, endoscopic, or histologic findings). The studies that fulfilled the inclusion criteria were identified, and their methodological quality was evaluated. Of the 2860 primary studies identified, two case-control and five cohort series fulfilled the inclusion criteria. Statistical analysis was performed by using the summary receiver operating characteristic (SROC) model.

RESULTS

The ranges of US sensitivity and specificity for the diagnosis of Crohn disease reported for the included series were 75%-94% and 67%-100%, respectively; the heterogeneity of these values prevented the calculation of a cumulative value. The SROC curve revealed a clear cutoff effect that depended on the chosen bowel wall thickness threshold. Sensitivity and specificity of 88% and 93%, respectively, were achieved when a bowel wall thickness threshold greater than 3 mm was used, and sensitivity and specificity of 75% and 97%, respectively, were achieved when a threshold greater than 4 mm was used.

CONCLUSION

US examination seems appropriate for confirming or excluding Crohn disease as a diagnosis in a clinical context characterized by a pretest probability of Crohn disease that ranges from 12% to about 60%. In particular, for Crohn disease limited to the ileum, US may represent a valid alternative to the small-bowel series, while for colonic involvement US may be useful in ruling out the diagnosis.

Clinical relevance of transabdominal ultrasonography and magnetic resonance imaging in patients with inflammatory bowel disease of the terminal ileum and large bowel

BACKGROUND

Ileocolonoscopy represents the diagnostic standard in the work-up of patients with inflammatory bowel diseases (IBD). Patients are often reluctant to be colonoscoped because of the invasiveness and pain sensation during colonoscopy.

AIMS

To compare the usefulness oftransabdominal ultrasound (US) and magnetic resonance imaging (MRI) in assessing disease extension and activity in patients with IBD restricted to the terminal ileum and large bowel.

PATIENTS AND METHODS

61 patients with IBD [37 Crohn's disease (CD) and 24 ulcerative colitis (UC)] were prospectively studied. All patients underwent clinical and laboratory assessment, ileocolonoscopy, transabdominal sonography, and MRI within 5 days. Involved bowel segments were defined as those with bowel wall thickness >3 mm and increased Doppler signal on US or contrast enhancement of the bowel wall on MRI. To compare disease activity endoscopic, MRI and US findings were graded with newly developed scores.

RESULTS

The segment-by-segment analysis revealed an overall accuracy of 89% for US and 73% for MRI in identifying active IBD. The accuracy was better in patients with UC than in patients with CD for both US and MRI. The endoscopic activity index (EAI) correlated stronger with the US activity index (r = 0.884) than with the MRI activity index (r = 0.344). The correlation of US and MRI activity indices with EAI was better in patients with UC compared with patients with CD. All three imaging methods showed a significant correlation with clinical disease activity in patients with UC but not in patients with CD.

CONCLUSION

This study provides strong evidence that US should be considered as a first-choice method for follow-up of patients with IBD of the terminal ileum and large bowel.

Hydrocolonic sonography for evaluating inflammatory bowel disease

OBJECTIVE

The purpose of our study was to compare the usefulness of hydrocolonic sonography and (99m)Tc-hexamethylpropyleneamine oxime (HMPAO)--labeled leukocyte scintigraphy in the examination of patients with inflammatory bowel disease, using precise sonographic criteria of bowel involvement.

SUBJECTS AND METHODS

Sixty-eight consecutive patients with active inflammatory bowel disease (34 ulcerative colitis and 34 Crohn's disease), 12 with inactive inflammatory bowel disease, and 10 control subjects were prospectively studied. Patients with active disease underwent clinical assessment, hydrocolonic sonography, scintigraphy, and colonoscopy within 72 hr, whereas patients with inactive disease and control subjects underwent clinical examination and hydrocolonic sonography.

RESULTS

Involvement of a colonic segment by active inflammatory bowel disease was best defined by mucosal thickness greater than 1.5 mm, bowel wall thickness greater than 4 mm, mucosal irregularity, or the absence of haustra; and involvement of the terminal ileum by bowel wall thickness greater than 4 mm. Using these criteria, hydrocolonic sonography had 100% sensitivity for identifying patients with active inflammatory bowel disease and a greater overall accuracy (87%) than scintigraphy (77%) in the assessment of disease extension. In addition, strong correlation was shown between a hydrocolonic sonography activity index and clinical and endoscopic activity indexes.

CONCLUSION

This prospective study provides precise sonographic criteria for the definition of bowel involvement by active inflammatory bowel disease. Hydrocolonic sonography has a greater accuracy than scintigraphy for assessing disease extension and activity. Therefore, hydrocolonic sonography should be considered a first-choice technique to complete the study of inflammatory bowel disease after confirmation of the diagnosis by histology.

Inflammatory bowel disease in children and young adults: correlation of sonographic and clinical parameters during treatment

OBJECTIVE

The objective of this study was to evaluate the sonographic findings of inflammatory bowel disease activity in children undergoing treatment.

SUBJECTS AND METHODS

Eighty-eight sonograms were obtained of 23 bowel segments in 17 children and young adults (age range, 10-21 years; mean, 16 years) with new or recurrent inflammatory bowel disease. Sixteen segments were involved with Crohn's disease and seven with ulcerative colitis. Serial sonography (range, two to eight examinations; mean, four per segment) was performed while patients underwent treatment. Bowel wall thickness measurements and color and power Doppler sonography grading were recorded and compared with clinical data.

RESULTS

All 17 patients had at least one abnormal bowel segment on initial sonography. The correlation was significant (p < 0.01). Agreement was 91% on direction of change over time between bowel wall thickness and Doppler grades, with 100% correlation between color and power Doppler sonography grades. In patients with Crohn's disease, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler grades with two of seven and four of seven clinical parameters, respectively. In patients with ulcerative colitis, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler sonography grades with four of seven and three of seven clinical parameters, respectively. The erythrocyte sedimentation rate correlated with all sonographic measurements in both patient groups. Combining bowel wall thickness and Doppler sonography, the percentage of agreement was significant in the direction of change, with five of seven clinical parameters in both patient groups.

CONCLUSION

Gray-scale and color or power Doppler sonography can show changes in disease activity in children and young adults undergoing treatment for inflammatory bowel disease.

Catheter probe assisted endoluminal US in inflammatory bowel disease

BACKGROUND

Use of an echocolonoscope to examine patients with inflammatory bowel disease is technically difficult. Catheter probe assisted endoluminal ultrasonography (US) may be a feasible alternative.

METHODS

Determination of demographic information and clinical disease activity was followed by colonoscopy with biopsy. Catheter probe assisted endoluminal US was performed with measurements of thickness of the intestinal wall and evaluation of the structure of the sonographic layers.

RESULTS

Twenty-eight patients, 7 with ulcerative colitis, 11 with Crohn's disease, and 10 healthy control subjects participated in a prospective study. Mean colonic wall thickness was 2.2 +/- 0.1 mm (controls) compared with 4. 1 +/- 0.4 mm (ulcerative colitis) (p < 0.001) and 4.4 +/- 0.4 mm (Crohn's disease) (p < 0.001). Among patients with ulcerative colitis, colonic wall thickness correlated with severity of colonoscopic changes (r = 0.84, p = 0.02). Among patients with Crohn's disease, loss of endosonographic layer structure correlated with disease activity score (r = 0.8, p = 0.003), and colonic wall thickness correlated with the severity of histologic changes (r = 0. 62, p = 0.04).

CONCLUSIONS

Catheter probe assisted endoluminal US is technically feasible in the care of patients with inflammatory bowel disease. Endosonographic measurements of colonic wall thickness and layer structure provide clinically significant information.

Practice guidelines for inflammatory bowel disease: an instrument for assessment

The development of practice guidelines is problematic because guidelines that are too broad have no value and guidelines that are highly specific cannot address the nuances of every patient's illness. In this article, we present the hypothesis that practice guidelines that provide specific objectives for assessment and intervention in inflammatory bowel disease can be used to measure practice variation. These guidelines are proposed as 15 specific objectives with options for intervention. These objectives could be used as an instrument to quantify variations in clinical practice and to assess the benefits of practice guidelines.

Ultrasonographically-guided fine-needle aspiration cytology in the diagnosis of colonic lesions

BACKGROUND

The use of fine-needle aspiration cytology (FNAC) in the diagnosis of colonic lesions was investigated.

METHODS

Some 22 patients (median age 71 years) with a colonic lesion identified on abdominal ultrasonography underwent ultrasonographically-guided FNAC using a 21-G needle. The sample was checked immediately by a cytopathologist for adequacy.

RESULTS

Eighteen patients had colonic carcinoma; aspiration cytology detected malignant epithelial cells consistent with colonic carcinoma in 17 patients and severely dysplastic cells in one patient. The sensitivity and specificity of ultrasonographically-guided FNAC in the diagnosis of colonic carcinoma was 94 and 100 per cent respectively. The remaining four patients had a diagnosis of ileocaecal tuberculosis, ileocaecal Crohn's disease, and metastatic adenocarcinoma in the liver with no identifiable primary (two patients). One demonstrated granulomata, grew acid-fast bacilli and the patient was treated for tuberculosis. One had inflammatory cells and the patient was found to have Crohn's disease on histology. The remaining two patients had confirmed metastatic adenocarcinoma in the liver on aspiration cytology but suspected colonic lesions were found to be benign on cytological examination and no primary lesion was subsequently demonstrated. There were no complications of FNAC and patients complained of minimal discomfort. There has been no evidence of tumour recurrence with a median follow-up of 12 (range 1-25) months.

CONCLUSION

Ultrasonographically-guided FNAC is a valid method for the diagnosis of colonic tumours.

Abdominal ultrasonography in the diagnosis of colonic cancer

BACKGROUND

Colonic cancer is normally diagnosed by barium enema or colonoscopy. Neither investigation is ideal, especially in the elderly patient. This study investigates the potential role of abdominal ultrasonography in the diagnosis of colorectal carcinoma.

METHODS

Fifty-four patients with known or suspected colonic carcinoma were referred for abdominal ultrasonography. A single radiologist performed scans on these patients and the site of any colonic mass or wall thickening considered to be consistent with a colonic carcinoma was reported. All carcinomas were confirmed by histology on tissue obtained at colonoscopy or surgery against which the ultrasonographic diagnosis was compared. Colonic masses detected in patients undergoing routine abdominal ultrasonography for abdominal symptoms were also reported.

RESULTS

Forty-five of the 54 patients referred had colonic carcinoma and abdominal ultrasonography detected 43 of the tumours and correctly identified the site of 41. The sensitivity, specificity and accuracy of abdominal ultrasonography in the detection of colonic tumours considered to be consistent with a colonic carcinoma was 96, 67 and 91 per cent respectively. Seven tumours were identified in patients referred before any other investigation had been carried out.

CONCLUSION

Abdominal ultrasonography may detect a colonic mass or wall thickening consistent with a colonic carcinoma with a high degree of accuracy and may be useful when barium enema or colonoscopy is not possible.

Ultrasound appearance of pseudomembranous colitis

A case illustrating that ultrasound can be useful in the diagnosis of pseudomembranous colitis is reported. Diagnosis of pseudomembranous colitis is usually made from microbiological or histopathological investigations. The ultrasound appearance of grossly thickened bowel wall with luminal narrowing is non-specific, but in the correct clinical context should suggest the diagnosis of pseudomembranous colitis.

Conventional radiography and ultrasonography in the diagnosis of small bowel obstruction and strangulation

Ninety-six patients, 45 men and 51 women (mean age 39 years, range 13- 90 years), with clinically acute abdomen were examined by conventional abdominal radiography and ultrasonography during a period of one year. Ultrasonography was performed with a linear transducer, which permitted study of morphology and motility of small bowel loops: distention, paralysis, intramural thickening, and extraluminal fluid. Nineteen cases of mechanical obstruction (9 simple and 10 of strangulation type) were observed. In the strangulation group ultrasonographic findings were positive in 91% whereas conventional radiography solely was positive in 30%. In the simple obstruction, 89% and 78%, respectively, were correctly diagnosed by the 2 techniques. Ultrasonography is recommended as a routine examination beside conventional abdominal films in acute abdomen.

Ultrasound examination of the small bowel: comparison with enteroclysis in patients with Crohn disease

BACKGROUND

Screening for inflammatory small bowel disease has hereto relied on barium examination, usually performed after duodenal intubation. A noninvasive technique for imaging of the small bowel in such patients would be preferable.

METHODS

A total of 59 patients were included in the study. A small bowel barium examination (SBE) was performed after duodenal intubation using a barium and air double-contrast technique. Ultrasound (US) of the right lower quadrant was performed with a 3.5- or 5-MHz transducer. The patients fasted overnight.

RESULTS

In 37 of 39 patients with a normal SBE, US was also normal. In 20 patients, SBE showed lesions compatible with Crohn disease and in 18 of these the US study showed thickening of the bowel wall. One of these patients later tested positive for Yersinia enterocolitica. There were two false-positive and two false-negative US examinations. For detection of inflammatory disease of the small bowel, US was calculated to have a sensitivity of 0.95, specificity of 0.93, accuracy of 0.93, predictive value of a positive test was 0.90, and a predictive value of a negative test was 0.95.

CONCLUSIONS

US, therefore, seems to be a reliable method in the workup of patients suspected of having inflammatory small bowel disease. Thereby, US probably can select patients for SBF.

Transvaginal sonographic diagnosis of sigmoid diverticulitis

The development of the transvaginal technique has allowed for high-resolution, detailed evaluation of the female pelvis. Although not previously emphasized, gut pathology can also be recognized with this technique. We report two cases of sigmoid diverticulitis which were prospectively diagnosed using endovaginal sonography. In both patients, pelvic sonogram was the first imaging study performed for evaluation of nonspecific abdominal pain.

The radiology of inflammatory bowel disease

This article presents various imaging modalities, including plain films, ultrasonography, magnetic resonance imaging, and radionuclide imaging, used for the diagnosis of inflammatory bowel disease (IBD), ulcerative colitis (UC), and Crohn's disease (CD). Also discussed are how to distinguish UC from CD and some of the intestinal complications of IBD.

Detection of Crohn's ileitis by endovaginal ultrasonography

Transabdominal ultrasonography in a female patient hospitalized for acute right lower quadrant pain revealed a nonspecific tubular structure in the region of the right adnexa. Endovaginal ultrasonography clearly showed this structure to be an abnormal loop of small bowel with its "target lesion" appearance and thickened wall. A tentative diagnosis of Crohn's disease was made. This was later confirmed by barium studies and histology.

Sonographic features of colon carcinoma seen with high-frequency transabdominal ultrasound

To assess the value of high-frequency ultrasonography as a diagnostic imaging procedure in patients with colon carcinoma, we first evaluated the sonograms of 37 patients who had been already diagnosed with contrast enema and/or colonoscopy as having colon carcinoma. As a result, the sonographic criteria for diagnosis of a possible colon carcinoma were (1) a localized and irregular thickening of the colonic wall with heterogenous low echogenicity, (2) an irregular contour, (3) a lack of demonstrable movement or change of configuration of the bowel on real-time scanning, and (4) absence of wall stratification. During the last 4 years, 41 consecutive patients had findings meeting our sonographic criteria. In 37 patients (90%), the presence of colon carcinoma was confirmed by contrast enema and/or colonoscopy. Our study suggests that high-frequency real-time ultrasonography may be a useful imaging technique in diagnosis of colon carcinoma.

Ultrasound Diagnosis of Carcinoma of the Colon

Ultrasound of the gastrointestinal tract is an extremely important, although underused, aspect of abdominal sonography. A case in which ultrasound examination led to a prospective diagnosis of unsuspected colon cancer is reported.

Sonographic evaluation of the abdomen in Henoch-Schonlein purpura

This study evaluates the role of ultrasound in the monitoring of abdominal symptoms of Henoch-Schonlein purpura. Clinical and radiological records of patients with gastrointestinal symptoms necessitating ultrasound scans were reviewed. Forty-four patients attended The Children's Hospital, Dublin, between August 1989 and December 1992, 15 (34%) of whom had abdominal ultrasound scans. There were 13 boys and two girls, ranging in age from 3.75 to 13.5 years. Abdominal radiographs in 13 patients did not add any significant information. Ultrasound detected thickened bowel wall in all 15 patients (0.4-1.1 cm), free peritoneal fluid in 10, ileus of affected loops in five, and bowel dilatation in eight. Serial ultrasound examinations in 12 patients followed the progress of bowel involvement, with resolution of mural thickening, return of peristalsis, reduction in ascites and bowel dilatation. There were seven intussusceptions in five patients, measuring 2.18-7.4 cm, which were documented as loose in four (i.e. where air or fluid lay between the intussusceptum and the intussuscipiens). Surgery was performed in three patients in the earlier years of the study; serial ultrasound monitoring has enabled a more conservative approach to be adopted in the latter years of the study. We conclude that ultrasound is the imaging modality of choice in evaluating the bowel manifestations of Henoch-Schonlein purpura. It provides an easy, noninvasive, objective method of monitoring patient progress. It allows direct visualization of bowel involvement and detection of complications such as intussusception. Routine abdominal radiographs are not recommended, unless perforation is clinically suspected.

Ultrasound scanning

Inflammatory or neoplastic bowel pathology is associated with thickening of the bowel wall. Ultrasound appearances reflect the pathological changes in the bowel. Crohn's disease is a transluminal disease leading to fibrosis. This fibrosis is responsible for the formation of an echo-poor halo surrounding a central echogenic zone. In the earlier stages with transmural oedema and inflammation, the halo assumes a ground glass appearance. Ulcerative colitis is a mucosal disease and hence the halo is a less prominent feature. Severe oedema in the bowel wall in fulminant ulcerative colitis can be recognized by the marked reduction of the haustral and central lumen of the colon.

The role of ultrasound scanning

Abdominal abscess, if left untreated, has a high mortality rate. Inadequate means of diagnosis and localization was responsible for this high mortality. Ultrasound now provides a simple non-invasive procedure permitting diagnosis with a high degree of sensitivity, although specificity is less commonly achieved. Abscesses do not have absolutely specific features, but given the appropriate clinical context and fine needle aspiration a diagnosis can be made in virtually 100% of cases, i.e. if the lesions can be identified and not obscured by bowel gas and examinations are not rendered difficult by surgical wounds and dressings. Diagnostic aspiration and therapeutic drainage are readily carried out using ultrasound guidance. Ultrasound is also of value in following the progress of lesions.

Transabdominal ultrasonography as the primary investigation in patients with suspected Crohn's disease or recurrence: a prospective study

Traditionally, patients with suspected or known and possible recurrent Crohn's disease have been investigated by small bowel barium radiology, which incurs a relatively high radiation dose. Despite patient selection a significant number have a normal barium examination. A prospective study was performed to evaluate the use of transabdominal ultrasound as the initial investigation in these two groups. One hundred and twenty-seven patients were examined, including 31 with a previous history of Crohn's disease. In the known Crohn's disease group there were 14 true positive ultrasound examinations and eight true negative, with six false positive and three false negative examinations. In the 96 patients not previously known to have Crohn's disease, there were 18 true positive and 70 true negative examinations, with two false positive and six false negative examinations. The overall sensitivity for ultrasound was 78% with a specificity of 91%. A significant learning curve was apparent in the early stages of study; in the last 64 patients the sensitivity was increased to 87%. These data support the use of ultrasound as the initial investigation in patients with suspected Crohn's disease or recurrence, prior to consideration for small bowel barium radiology, to reduce the large number of unnecessary small bowel barium examinations currently being performed.