Mechanisms, Management, and Treatment of Fibrosis in Patients With Inflammatory Bowel Diseases

In the last 10 years, we have learned much about the pathogenesis, diagnosis, and management of intestinal fibrosis in patients with inflammatory bowel diseases. Just a decade ago, intestinal strictures were considered to be an inevitable consequence of long-term inflammation in patients who did not respond to anti-inflammatory therapies. Inflammatory bowel diseases-associated fibrosis was seen as an irreversible process that frequently led to intestinal obstructions requiring surgical intervention. This paradigm has changed rapidly, due to the antifibrotic approaches that may become available. We review the mechanisms and diagnosis of this serious complication of inflammatory bowel diseases, as well as factors that predict its progression and management strategies.

Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review

SMALL-BOWEL CAPSULE ENDOSCOPY (SBCE)

1: ESGE recommends that prior to SBCE patients ingest a purgative (2 L of polyethylene glycol [PEG]) for better visualization.Strong recommendation, high quality evidence.However, the optimal timing for taking purgatives is yet to be established. 2: ESGE recommends that SBCE should be performed as an outpatient procedure if possible, since completion rates are higher in outpatients than in inpatients.Strong recommendation, moderate quality evidence. 3: ESGE recommends that patients with pacemakers can safely undergo SBCE without special precautions.Strong recommendation, low quality evidence. 4: ESGE suggests that SBCE can also be safely performed in patients with implantable cardioverter defibrillators and left ventricular assist devices.Weak recommendation, low quality evidence. 5: ESGE recommends the acceptance of qualified nurses and trained technicians as prereaders of capsule endoscopy studies as their competency in identifying pathology is similar to that of medically qualified readers. The responsibility of establishing a diagnosis must however remain with the attending physician.Strong recommendation, moderate quality evidence. 6: ESGE recommends observation in cases of asymptomatic capsule retention.Strong recommendation, moderate quality evidence.In cases where capsule retrieval is indicated, ESGE recommends the use of device-assisted enteroscopy as the method of choice.Strong recommendation, moderate quality evidence.

DEVICE-ASSISTED ENTEROSCOPY (DAE)

1: ESGE recommends performing diagnostic DAE as a day-case procedure in patients without significant underlying co-morbidities; in patients with co-morbidities and/or those undergoing a therapeutic procedure, an inpatient stay is recommended.Strong recommendation, low quality evidenceThe choice between different settings also depends on sedation protocols.Strong recommendation, low quality evidence. 2: ESGE suggests that conscious sedation, deep sedation, and general anesthesia are all acceptable alternatives: the choice between them should be governed by procedure complexity, clinical factors, and local organizational protocols.Weak recommendation, low quality evidence. 3: ESGE recommends that the findings of previous diagnostic investigations should guide the choice of insertion route.Strong recommendation, moderate quality evidence.If the location of the small-bowel lesion is unknown or uncertain, ESGE recommends that the antegrade route should be generally preferred.Strong recommendation, low quality evidence.In the setting of massive overt bleeding, ESGE recommends an initial antegrade approach.Strong recommendation, low quality evidence. 4: ESGE recommends that, for balloon-assisted enteroscopy (i. e., single-balloon enteroscopy [SBE] and double-balloon enteroscopy [DBE]), small-bowel insertion depth should be estimated by counting net advancement of the enteroscope during the insertion phase, with confirmation of this estimate during withdrawal.Strong recommendation, low quality evidence.ESGE recommends that, for spiral enteroscopy, insertion depth should be estimated during withdrawal.Strong recommendation, moderate quality evidence. Since the calculated insertion depth is only a rough estimate, ESGE recommends placing a tattoo to mark the identified lesion and/or the deepest point of insertion.Strong recommendation, low quality evidence. 5: ESGE recommends that all endoscopic therapeutic procedures can be undertaken at the time of DAE.Strong recommendation, moderate quality evidence.Moreover, when therapeutic interventions are performed, additional specific safety measures are needed to prevent complications.Strong recommendation, high quality evidence.

CT of acute bowel ischemia

Bowel ischemia may be caused by many conditions and manifest with typical or atypical and specific or nonspecific clinical, laboratory, and radiologic findings. It may mimic various intestinal diseases and be confused with certain nonischemic conditions clinically and at computed tomography (CT). Bowel ischemia severity ranges from mild (generally transient superficial changes of intestinal mucosa) to more dangerous and potentially life-threatening transmural bowel wall necrosis. Causes of critically reduced blood flow to the bowel are diverse, ranging from occlusions of mesenteric arteries or veins to complicated bowel obstruction and overdistention. CT can demonstrate changes in ischemic bowel segments accurately, is often helpful in determining the primary cause of ischemia, and can demonstrate important coexistent findings or complications. Unfortunately, common CT findings in bowel ischemia are not specific, and specific findings are rather uncommon. Therefore, it often is a combination of nonspecific clinical, laboratory, and radiologic findings-especially detailed knowledge about the pathogenesis of acute bowel ischemia in different conditions-that helps most in correct interpretation of CT findings. To improve understanding of this complex heterogeneous entity, this article provides an overview of the anatomy and physiology of mesenteric perfusion and discussions of causes and pathogenesis of acute bowel ischemia, CT findings in various types of acute bowel ischemia, and potential pitfalls of CT.

Clinical experience with 99mTc-hexamethylpropylene-amineoxime for labelling leucocytes and imaging inflammation

Hexamethylpropylene-amineoxime (HMPAO) forms a lipid-soluble neutral complex with 99mTc which is rapidly incorporated into leucocytes in vitro. In six patients with suspected or known inflammatory disease, a "mixed" leucocyte suspension isolated from 85 ml blood anticoagulated with acid-citrate-dextrose was labelled by 99mTc-HMPAO with a mean efficiency of 47% (SE2%), of which 78% (3) was taken up by granulocytes. Activity eluted more rapidly from other cell types in vitro than from granulocytes, which remained firmly labelled. Mean initial biodistribution of the label and granulocyte recovery in blood of 32% (8) at 30-40 min showed that the granulocytes were not significantly activated during labelling. All six patients were positive for inflammatory disease, as early as 30 min in five patients and at 3 h in the sixth; they all remained positive at 20-24 h. Four patients also received 111In-labelled "pure" granulocytes. In terms of detail, the 99mTc images were comparable or superior to the 111In images.

Diagnostic accuracy of transvaginal sonography for deep pelvic endometriosis

OBJECTIVE

To determine the accuracy of transvaginal sonography (TVS) for the diagnosis of deep pelvic endometriosis.

METHODS

In a prospective study, 142 women with clinical signs of endometriosis underwent TVS followed by surgical and histopathological investigations. The presence and extent of endometriosis involving the uterosacral ligaments, vagina, rectovaginal septum, intestines, bladder and ovaries shown by TVS were compared with surgical and histological findings. The sensitivity, specificity, predictive values and accuracy of TVS for predicting deep pelvic endometriosis were assessed.

RESULTS

Ovarian and deep pelvic endometriosis were found by surgery and histology in respectively 83 (58.5%) and 79 (55.6%) of the 142 patients. The sensitivity, specificity, and positive and negative predictive values of TVS for the diagnosis of deep pelvic endometriosis were 78.5%, 95.2%, 95.4% and 77.9%, respectively. The sensitivity and specificity of TVS for endometriotic involvement of the uterosacral ligaments, vagina, rectovaginal septum and intestines were 70.6% and 95.9%, 29.4% and 100%, 28.6% and 99.3%, and 87.2% and 96.8%, respectively. The sensitivity and specificity of TVS for bladder involvement were 71.4% and 100%, respectively.

CONCLUSION

TVS accurately diagnoses intestinal and bladder endometriosis, but is less accurate for uterosacral, vaginal and rectovaginal septum involvement.

Bowel endometriosis: presentation, diagnosis, and treatment

Bowel endometriosis opens a new frontier for the gynecologist, as it forces the understanding of a new anatomy, a new physiology, and a new pathology. Although some women with bowel endometriosis may be asymptomatic, the majority of them develop a variety of gastrointestinal complains. No clear guideline exists for the evaluation of patients with suspected bowel endometriosis. Given the fact that, besides rectal nodules, bowel endometriosis can not be diagnosed by physical examination, imaging techniques should be used. Several techniques have been proposed for the diagnosis of bowel endometriosis including double-contrast barium enema, transvaginal ultrasonography, rectal endoscopic ultrasonography, magnetic resonance imaging, and multislice computed tomography enteroclysis. Medical management of bowel endometriosis is currently speculative; expectant management should be carefully balanced with the severity of symptoms and the feasibility of prolonged follow-up. Several studies demonstrated an improvement in quality of life after extensive surgical excision of the disease. Bowel endometriotic nodules can be removed by various techniques: mucosal skinning, nodulectomy, full thickness disc resection, and segmental resection. Although the indications for colorectal resection are controversial, recent data suggest that aggressive surgery improves symptoms and quality of life.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to describe the varied appearance of bowel endometriosis, recall that it is difficult to diagnose preoperatively, and explain that surgical treatment offers the best treatment in symptomatic patients through a variety of surgical techniques which is best accomplished with a team approach.

Small-bowel diseases: prospective evaluation of multi-detector row helical CT enteroclysis in 107 consecutive patients

PURPOSE

To prospectively evaluate multi-detector row helical computed tomographic (CT) enteroclysis for the depiction of small-bowel diseases.

MATERIALS AND METHODS

The study group included 107 patients who were suspected of having small-bowel tumor (n = 8), active inflammatory small-bowel disease (n = 18), unexplained gastrointestinal bleeding (n = 36), refractory celiac sprue (n = 14), and low-grade small-bowel obstruction (n = 31). A nasoenteric tube was positioned into the duodenojejunal junction by using fluoroscopic guidance and water was infused with a pressure-controlled pump. After intravenous administration of 120 mL of iodinated contrast material, multi-detector row helical CT enteroclysis images were obtained with 4 x 2.5 mm collimation (four detector rows and 2.5-mm section thickness). Multi-detector row helical CT enteroclysis findings were analyzed by two readers working in consensus. Findings were compared with the results of endoscopy, enteroscopy, videocapsule endoscopy, histopathologic analysis, or clinical follow-up.

RESULTS

Multi-detector row helical CT enteroclysis was well tolerated in 106 patients; one patient complained of abdominal pain after the examination. Multi-detector row helical CT enteroclysis allowed the diagnosis of small-bowel masses (n = 21), active Crohn disease (n = 9), small-bowel tuberculosis (n = 2), small-bowel lymphoma complicating celiac disease (n = 4), and confirmed low-grade small-bowel obstruction (n = 12). Multi-detector row helical CT enteroclysis demonstrated normal findings in 60 patients. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of multi-detector row helical CT enteroclysis were 100%, 95%, 97%, 94%, and 100%, respectively.

CONCLUSION

Multi-detector row helical CT enteroclysis allows depiction of small-bowel diseases in patients suspected of having small-bowel conditions.

Bowel obstruction: evaluation with CT

Eighty-four computed tomographic (CT) scans from patients referred for bowel obstruction between January 2, 1988, and December 31, 1989, were retrospectively evaluated. A pair of radiologists without knowledge of patient histories determined the presence or absence of bowel obstruction. Sixty-four patients ultimately proved to have intestinal obstruction, and 20 did not. Diagnosis was established by means of surgery (n = 39), barium studies (n = 17), and clinical course (n = 28). Causes of obstruction included adhesions (n = 37), metastases (n = 6), primary tumor (n = 7), Crohn disease (n = 4), hernia (n = 3), hematoma (n = 2), colonic diverticulitis (n = 2), and other (n = 3). In addition, 83 CT examinations in patients with no history or indication of intestinal obstruction were simultaneously reviewed. The overall sensitivity was 94%, specificity was 96%, and accuracy was 95%. The cause of obstruction was correctly predicted in 47 of 64 cases (73%). Intestinal obstruction was not diagnosed in any of the 83 control patients. CT is most useful in patients with a history of abdominal malignancy and in patients who have not been operated on and who have signs of infection, bowel infarction, or a palpable abdominal mass.

Female pelvic organ prolapse: a comparison of triphasic dynamic MR imaging and triphasic fluoroscopic cystocolpoproctography

OBJECTIVE

This study compared dynamic MR imaging with fluoroscopic cystocolpoproctography for the detection and measurement of prolapse of pelvic organs.

SUBJECTS AND METHODS

Ten patients underwent triphasic dynamic MR imaging and triphasic fluoroscopic cystocolpoproctography with identical amounts of contrast material to opacify the bladder, vagina, and rectum. The dynamic MR imaging procedure included cine-loop presentation. Each examination was analyzed to determine the presence and extent of prolapse of pelvic organs based on specific measurements.

RESULTS

Both dynamic MR imaging and fluoroscopic cystocolpoproctography revealed 10 rectoceles (mean extents, 2.85 and 2.45 cm, respectively). Nine cystoceles were revealed by both dynamic MR imaging (mean extent, 4.05 cm) and fluoroscopy (mean extent, 4.55 cm). Seven enteroceles were revealed, one of which was initially not seen on dynamic MR imaging. Two sigmoidoceles were revealed, one of which was not seen on fluoroscopy. The mean extent of the enteroceles and sigmoidoceles on dynamic MR imaging was 3.50 cm, and the mean extent on fluoroscopy was 4.25 cm. Nine of the 10 patients were able to defecate in the supine position on the MR imaging table. Patients were divided equally in their preference for dynamic MR imaging or fluoroscopic cystocolpoproctography.

CONCLUSION

Triphasic dynamic MR imaging and triphasic fluoroscopic cystocolpoproctograpy show similar detection rates for prolapse of pelvic organs. Although dynamic MR imaging underestimates the extent of cystoceles and enteroceles, it has the advantage of revealing all pelvic organs and the pelvic floor musculature in a multiplanar cine-loop presentation.

Surgical management of thrombotic acute intestinal ischemia

OBJECTIVE

To evaluate the University of Kentucky experience in treating acute intestinal ischemia to elucidate factors that contribute to survival.

SUMMARY BACKGROUND DATA

Acute intestinal ischemia is reported to have a poor prognosis, with survival rates ranging from 0% to 40%. This is based on several reports, most of which were published more than a decade ago. Remarkably, there is a paucity of recent studies that report on current outcome for acute mesenteric ischemia.

METHODS

A comparative retrospective analysis was performed on patients who were diagnosed with acute intestinal ischemia between May 1993 and July 2000. Patients were divided into two cohorts: nonthrombotic and thrombotic causes. The latter cohort was subdivided into three etiologic subsets: arterial embolism, arterial thrombosis, and venous thrombosis. Patient demographics, clinical characteristics, risk factors, surgical procedures, and survival were analyzed. Survival was compared with a collated historical series.

RESULTS

Acute intestinal ischemia was diagnosed in 170 patients. The etiologies were nonthrombotic (102/170, 60%), thrombotic (58/170, 34%), or indeterminate (10/170, 6%). In the thrombotic cohort, arterial embolism accounted for 38% (22/58) of the cases, arterial thrombosis for 36% (21/58), and venous thrombosis for 26% (15/58). Patients with venous thrombosis were younger. Venous thrombosis was observed more often in men; arterial thrombosis was more frequent in women. The survival rate was 87% in the venous thrombosis group versus 41% and 38% for arterial embolism and thrombosis, respectively. Compared with the collated historical series, the survival rate was 52% versus 25%.

CONCLUSIONS

These results indicate that the prognosis for patients with acute intestinal ischemia is substantially better than previously reported.

Cross-sectional imaging in Crohn disease

The role of cross-sectional imaging in the diagnosis of Crohn disease has expanded with recent technologic advances in computed tomography (CT) and magnetic resonance (MR) imaging that allow rapid acquisition of high-resolution images of the intestines. To acquire images of diagnostic quality, administration of a fairly large amount of intraluminal contrast agent prior to examination and scanning with intravenous contrast material injection are necessary. Both CT and MR imaging are reported to have a sensitivity of over 95% for the detection of Crohn disease; however, they may not allow early diagnosis. Colonoscopy and conventional enteroclysis studies are indicated for patients with early-stage disease. At more advanced stages, CT and MR imaging can help identify and characterize pathologically altered bowel segments as well as extraluminal lesions (eg, fistulas, abscesses, fibrofatty proliferation, increased vascularity of the vasa recta, mesenteric lymphadenopathy). These modalities can also clearly depict inflammatory lesion activity and conditions that require elective gastrointestinal surgery, thereby aiding in treatment planning. In the clinical setting, CT is currently the imaging modality of choice at most institutions; however, it is expected that MR imaging will soon play a comparable role. CT or MR imaging should be included in a comprehensive evaluation of patients with Crohn disease, along with conventional imaging and clinical and laboratory tests.

A pattern approach to the abnormal small bowel: observations at MDCT and CT enterography

OBJECTIVE

Imaging of the vast array of pathologic processes occurring in the small bowel has been facilitated by recent advances, including the use of MDCT scanners that acquire isotropic data and neutral oral contrast agents that improve small-bowel distention.

CONCLUSION

This review shows how a systematic pattern approach can be used to narrow the differential diagnosis when an abnormal small-bowel loop is detected on MDCT.

Female pelvic organ prolapse: diagnostic contribution of dynamic cystoproctography and comparison with physical examination

OBJECTIVE

The aim of this study was to assess the contribution of dynamic cystoproctography to the evaluation of female pelvic organ prolapse and to compare this contribution with that of physical examination.

MATERIALS AND METHODS

The presence or absence of rectocele, enterocele, sigmoidocele, and cystocele on physical examination and on cystoproctography was retrospectively analyzed in 170 consecutive patients. For each of these diagnostic methods, organ prolapse was graded as small, moderate, or large on the basis of specific, defined measurements.

RESULTS

A rectocele was detected by proctography in 155 patients (91%); 119 (77%) of these rectoceles were also found on physical examination. Barium trapping at proctography was related to rectocele size. Proctography showed an enterocele in 47 patients (28%); 24 (51%) of these enteroceles were also found on physical examination. Physical examination also found 44 enteroceles that could not be corroborated radiologically. At proctography, the enteroceles were relatively large, extending an average of 7.3 cm below the vaginal apex. Eight patients had sigmoidoceles, none of which were found on physical examination. A cystocele was shown by cystoproctography in 159 patients (94%); 132 (83%) of these cystoceles were also found on physical examination.

CONCLUSION

The correlation between finding prolapsed pelvic organs on dynamic cystoproctography and finding them on physical examination varies. Most radiographically detected rectoceles and cystoceles are found on physical examination, whereas the correlation for enteroceles and sigmoidoceles is poor. Dynamic cystoproctography provides direct visualization and quantification of female pelvic organ prolapse, information that usually can only be inferred by physical examination.

Meta-analysis: capsule enteroscopy vs. conventional modalities in diagnosis of small bowel diseases

BACKGROUND

Prospective trials support the role of capsule enteroscopy as an improvement in diagnosing mucosal lesions in the small bowel.

AIM

To determine the diagnostic yield and safety of capsule enteroscopy vs. alternative diagnostic modalities (such as push enteroscopy, small bowel follow-through or enteroclysis) in patients with small bowel diseases.

METHODS

A search for prospective studies comparing capsule enteroscopy vs. other diagnostic tests in adults was performed between 1966 and 2005. Selected articles were included in a meta-analysis. Three analyses were run separately, all included studies and studies having occult gastrointestinal bleeding or Crohn's disease as main outcome.

RESULTS

Seventeen studies (526 patients) met inclusion criteria. The rate difference (i.e. the absolute pooled difference in the rate of positive findings) between capsule enteroscopy and alternative modalities for small bowel disease was 41% (95% CI 35.6-45.9); 37% (95% CI 29.6-44.1) for occult gastrointestinal bleeding; and 45% (95% CI 30.9-58.0) for Crohn's disease. Failure to visualize the caecum occurred in 13%, significantly more often in occult bleeders (17%) than in patients with Crohn's disease (8%) (P < 0.006). Adverse events were recorded in 29 patients (6%). Capsule retention was more frequent in patients with Crohn's disease (3% vs. 1%, OR 4.37).

CONCLUSIONS

Capsule enteroscopy proved significantly superior to push enteroscopy and small bowel radiology in the diagnosis of ileal diseases. Capsule enteroscopy is safe, though prior radiology is still necessary to rule out small bowel strictures in patients with known or suspected Crohn's disease.

Mucocele of the appendix and pseudomyxoma peritonei

Mucocele of the appendix is a descriptive term for an abnormal mucous accumulation distending the appendiceal lumen. Pseudomyxoma peritonei is characterized by mucinous ascites and implants throughout the abdominal cavity. Thirty-four cases of appendiceal mucocele and seven cases of pseudomyxoma peritonei of appendiceal origin on file at the Armed Forces Institute of Pathology were reviewed for their clinical, pathologic, and radiologic findings. These cases provided examples of the major radiologic findings reported in this entity. Previously unreported findings of dependent echoes within some mucoceles on sonography and pseudomyxoma peritonei tracking along the umbilical vein remnant or mimicking an intrahepatic mass are presented.

Current status of small bowel radiography

BACKGROUND

In the past, small bowel examinations were usually ordered for the sake of "completeness." As a result, small bowel radiography was performed casually and without attention to detail. This review examines pertinent clinical issues and the recent contribution of small bowel radiography to the evaluation and management of the patient with suspected small bowel disease. Recommendations for the clinical utilization of small bowel radiography are discussed.

METHODS

Analysis of pertinent citations addressing valid indications for, and technique of, small bowel radiography from 1980 to July 1995 through a computerized bibliographic search (Medline and Current Contents).

RESULTS

Accepted clinical indications for small bowel radiography include (1) unexplained gastrointestinal bleeding, (2) possible small bowel tumor, (3) small bowel obstruction, (4) Crohn disease, and (5) malabsorption. The current literature reflects the limitations of the conventional small bowel follow-through, various modifications to improve its clinical yield, the important contribution of enteroclysis in the workup, and subsequent management of patients with possible small bowel disease. A controversy in the radiology literature exists as to whether to use the small bowel follow-through or enteroclysis as the primary method of examining the small bowel.

CONCLUSION

The thoughtful selection of patients by clinicians for small bowel radiography is essential to make radiologic evaluation cost effective. The incidence of disease of the small intestine is low and is associated with nonspecific symptoms. Because of the inherent difficulty of visualizing numerous loops of an actively peristalsing bowel, a reliable imaging method is needed that not only detects small or early structural abnormality but also accurately documents normalcy. The yield of information provided by enteroclysis and its high negative predictive value suggests that it should be the primary method for small bowel examination. The "overhead"-based conventional small bowel follow-through should be abandoned. The "fluoroscopy"-based small bowel follow-through augmented when necessary by the peroral pneumocolon or the gas-enhanced double-contrast follow-through method is an acceptable alternative when enteroclysis is not possible.

CT features of systemic lupus erythematosus in patients with acute abdominal pain: emphasis on ischemic bowel disease

PURPOSE

To evaluate the computed tomographic (CT) features of systemic lupus erythematosus (SLE) in patients with acute abdominal pain. Special emphasis was placed on the analysis of ischemic bowel disease.

MATERIALS AND METHODS

The authors retrospectively reviewed the images from 39 abdominal CT examinations performed in 33 patients with SLE and acute abdominal pain. Images were evaluated for bowel wall changes, mesenteric changes, fluid collection, retroperitoneal lymphadenopathy, peritoneal enhancement, and hepatomegaly as well as for changes in other abdominal organs. Ischemic bowel disease was diagnosed if at least three of the following signs were seen: bowel wall thickening, target sign, dilatation of intestinal segments, engorgement of mesenteric vessels, and increased attenuation of mesenteric fat.

RESULTS

Thirty-one (79%) of the 39 examinations had CT findings diagnostic of ischemic bowel disease, including symmetric bowel wall thickening (n = 29), target sign (n = 26), and mesenteric vascular engorgement and haziness (n = 31). In 24 cases, bowel wall thickening was multifocal, with variable length, and did not appear to be confined to a single vascular territory.

CONCLUSION

The most common CT finding in patients with SLE and acute abdominal pain is ischemic bowel disease. CT is useful for detecting the primary cause of gastrointestinal symptoms, planning treatment, and monitoring for infarction or perforation.

Multidetector-row helical CT enteroclysis

Currently, CT-E is not recommended as the first-line examination in patients when mucosal detail is required. Double-contrast barium air enteroclysis has advantages in demonstrating small mucosal abnormalities. The authors find CT-E of value in the work-up of patients with symptoms of intermittent small bowel obstruction, particularly those with a history of prior abdominal surgery; in the further work-up of selected patients with high-grade obstruction in whom general surgeons prefer initial conservative management (immediate postoperative small bowel obstruction, patients with history of prior abdominal surgery for malignant tumor, history of radiation treatment, and possible internal extraintestinal fistulae); in looking for complications of small bowel Crohn's disease; and in the patient with unexplained anemia or gastrointestinal bleeding. In a series of patients who had both abdominal CT and barium enteroclysis done, each examination provided unique and complimentary diagnostic information. Because CT-E combines the advantages of both methods of examination, is it the optimum imaging work-up in the investigation of small bowel disease? Further research and clinical experience will define the precise role of CT-E in the investigation of small bowel disease. Experience with this method of examination is limited to a few institutions, performed by investigators with interest in small bowel diseases. The addition of cross-sectional display and multiplanar reformatting made possible by multidetector-row helical CT to enteral volume change and the use of multifunctional nasointestinal catheters make CT-E an important tool in the investigation of small bowel disease. Experience has shown the increased reliability of any method of examining the small bowel that challenges intestinal wall distensibility by fluid enteral volume infusion.

Wireless capsule endoscopy detects small bowel ulcers in patients with normal results from state of the art enteroclysis

BACKGROUND

Wireless capsule endoscopy (WCE) is a new technology for small bowel imaging.

AIM

To report our initial experience with sensitivity of high quality enteroclysis in patients with small bowel ulcers detected by WCE.

METHODS

Medical records of all patients referred for WCE from December, 2001 to April, 2002 at our institution were reviewed. All patients had negative upper and lower endoscopies and small bowel barium studies before WCE.

RESULTS

There were 40 patients (19 female, mean age 57.3 yr) during this study period. Three patients had multiple small bowel ulcers detected by WCE. One with ileal ulcers and abdominal pain had an enteroclysis at another hospital before WCE. Review of the study at our institution showed that it was of excellent quality and was normal. Two patients with chronic iron deficiency anemia had multiple small bowel ulcers and were referred after WCE for a repeat small bowel barium study by biphasic enteroclysis performed by experienced GI radiologists. The radiologists were told in advance of the WCE findings. Both studies were considered technically to be of perfect quality. Despite this, both studies were negative. All 3 patients improved after therapy for Crohn's disease.

CONCLUSIONS

Our data indicates that WCE may be more sensitive for small bowel ulcers than the best enteroclysis available.

Acute nontraumatic abdominal pain in adult patients: abdominal radiography compared with CT evaluation

PURPOSE

To compare the diagnostic yield of abdominal radiography with that of computed tomography (CT) in adult patients presenting to the emergency department with nontraumatic abdominal pain.

MATERIALS AND METHODS

Records of 1,000 consecutive patients presenting to the emergency department with acute abdominal pain from April to June 1998 were retrospectively reviewed. A total of 871 patients underwent abdominal radiography, and 188 underwent abdominal CT. The report interpretations of the abdominal radiographs and CT scans were divided into normal, nonspecific, and abnormal categories. Final discharge diagnoses were compared with the interpretations of the imaging examination results, and sensitivities and specificities of each modality were calculated and compared.

RESULTS

Interpretation of abdominal radiographs was nonspecific in 588 (68%) of 871 patients, normal in 200 (23%), and abnormal in 83 (10%). The highest sensitivity of abdominal radiography was 90% for intraabdominal foreign body and 49% for bowel obstruction. Abdominal radiography had 0% sensitivity for appendicitis, pyelonephritis, pancreatitis, and diverticulitis. Sensitivities of abdominal CT were highest for bowel obstruction and urolithiasis at 75% and 68%, respectively.

CONCLUSION

Abdominal radiographs are not sensitive in the evaluation of adult patients presenting to the emergency department with nontraumatic abdominal pain.

Microvascular studies in human radiation bowel disease

The microvasculature was investigated in the normal bowel (n = 43 patients) and in radiation bowel disease (n = 18 patients). Tissue samples obtained from postoperative colectomy specimens in which the intramural vessels had been perfused with barium sulphate suspension were examined. Microradiography was used to study vascular pattern which was abnormal in radiation bowel disease. A recently described radiograph fluorescence system was used to estimate barium concentration, and hence microvascular volume. The radiation group showed a highly significant reduction in barium concentration (p less than 0.001), when compared with the normal group. This reduction was diffuse in samples from 15 patients who had received combined intracavity and external radiotherapy, but localised in two patients who had received intracavity treatment only. It is concluded that microvascular compromise is an important factor in the natural history of radiation bowel disease.

Algorithmic approach to CT diagnosis of the abnormal bowel wall

Computed tomography demonstrates intestinal wall abnormalities that can be analyzed by categorizing attenuation changes in the intestinal wall and transposing morphologic characteristics learned from barium studies. These attenuation patterns include white, gray, water halo sign, fat halo sign, and black. The white pattern represents avid contrast material enhancement that uniformly affects most of the thickened bowel wall. If the bowel wall is enhanced to a degree equal to or greater than that of venous opacification in the same scan, it should be classified in the white attenuation pattern. Common diagnoses with this pattern include idiopathic inflammatory bowel diseases and vascular disorders. The gray pattern is defined as a thickened bowel wall with limited enhancement whose homogeneous attenuation is comparable with that of enhanced muscle. This pattern is used to differentiate between benign and malignant disease, but it is the least specific of the patterns and should be combined with morphologic observations. The water halo sign indicates stratification within a thickened bowel wall that consists of either two or three continuous, symmetrically thickened layers. Common diagnoses with this sign include idiopathic inflammatory bowel diseases, vascular disorders, infectious diseases, and radiation damage. The fat halo sign refers to a three-layered target sign of thickened bowel in which the middle or "submucosal" layer has a fatty attenuation. Common diagnoses with this sign include Crohn disease in the small intestine and idiopathic inflammatory bowel diseases in the colon. Black attenuation is the equivalent of pneumatosis, and this pattern is commonly seen in ischemia, infection, and trauma.

The current status of multidetector row CT and three-dimensional imaging of the small bowel

Radiologists have played an important role in evaluation of patients with small bowel pathology. The small bowel series and, later, enteroclysis were the mainstays in radiologic diagnosis of many small bowel diseases, because the resolution and speed of CT was limited. Continued improvements in CT technology over the last 2 decades have resulted in a expanding role of CT for evaluation of the gastrointestinal tract, including the small intestine. Many conditions, such as small bowel obstruction and ischemia, that would traditionally be imaged with other modalities (small bowel series or angiography) are now routinely imaged with CT. The development of MDCT and improvements in 3D imaging systems have greatly improved the ability to examine the small bowel and mesenteric vasculature. With the introduction of new CT oral contrast agents and faster 32-detector row CT scanners, the diagnosis and evaluation of patients with small bowel disease will continue to improve.

Ultrasonographic detection of intestinal complications in Crohn's disease

The aim of this study was to evaluate the sensitivity and specificity of ultrasound (US) in assessing the main abdominal complications of Crohn's disease (CD), such as strictures, fistulas and abscesses. A series of 98 consecutive inpatients with complicated and uncomplicated Crohn's disease, having undergone a complete endoscopic and radiographic evaluation of the intestinal tract, entered the study. In particular, in these patients the presence of strictures, fistulas, and abscesses, detected by means of colonoscopy, small bowel x-ray, double-contrast barium enema, and computed tomography, was also assessed by means of transabdominal US. US sensitivity and specificity in the assessment of stenosis of Crohn's disease were 74.4% and 93.1%, respectively. When ileal and colonic stenosis were considered separately, transabdominal US correctly assessed 84.6% of ileal stenosis and 58.8% of colonic stenosis. Eight of 12 fistulas were detected, but only 50% of enteroenteric fistulas were diagnosed. The presence of abscesses was correctly detected in 83.3% of cases by means of US. Our data suggest that US is a suitable complementary method for the detection of abdominal complications of Crohn's disease, such as strictures and abscesses; however, its usefulness in assessing enteroenteric fistulas seems to be fairly limited.

Multislice CT enteroclysis in the diagnosis of bowel endometriosis

This prospective study aims to evaluate the efficacy of multislice computed tomography combined with colon distension by water enteroclysis (MSCTe) in determining the presence and depth of bowel endometriotic lesions. Ninety-eight women with symptoms suggestive of colorectal endometriosis underwent MSCTe; locations, number of nodule/s, size of the nodule/s and depth of bowel wall infiltration were determined. Independently from the findings of MSCTe, all women underwent laparoscopy. MSCTe findings were compared with surgical and histological results. Abnormal findings suggestive of bowel endometriotic nodules were detected by MSCTe in 75 of the 76 patients with bowel endometriosis. MSCTe identified 110 (94.8%) of the 116 bowel endometriotic nodules removed at surgery; 6 nodules missed at MSCTe were located on the rectum. MSCTe correctly determined the degree of infiltration of the bowel wall in all of the 34 serosal bowel nodules identified at MSCTe. In six nodules reaching the submucosa, the depth of infiltration was underestimated by MSCTe. MSCTe had a sensitivity of 98.7%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 95.7% in identifying women with bowel endometriosis. MSCTe is effective in determining the presence and depth of bowel endometriotic lesions.