MR enteroclysis

Comparison of Magnetic Resonance Enterography Global Score (MEGS) with indices of Crohn's disease activity in South Asian population

PURPOSE

Assessment of disease activity in Crohn's helps predict important clinical outcomes. Among the various modalities available to assess disease activity, magnetic resonance enterography (MRE) is considered a safe and reliable imaging option. Various MRE-based scoring systems have been developed to measure disease activity, one of which being the MRE global score (MEGS). We aimed to correlate MEGS with some of the important indices of Crohn's disease activity.

METHODOLOGY

Crohn's disease patients referred for MRE were included in the study. Along with demographic profile and relevant investigations, MRE parameters related to MEGS were also assessed.

RESULT

A total of 47 patients were recruited for the study. Their median age was 34 years (range 18-68 years), and male:female ratio was 16:31. There was modest positive correlation between MEGS and faecal calprotectin (r = 0.3, p = 0.04), CRP level (r = 0.34, p = 0.02) and Harvey Bradshaw index (r = 0.3, p = 0.043), respectively. However, there was strong correlation between segmental MEGS and Simple Endoscopic Score in those with terminal ileal disease (r = 0.81, p < 0.001). Mural thickness was the only MRE parameter that correlated with active disease (OR - 1.35, 95% CI 1.01, 1.81, p = 0.041) on multivariate analysis. There was moderate inter-observer agreement (Lin's r = 0.78, p < 0.001).

CONCLUSION

MEGS showed modest correlation with indices of Crohn's disease activity which corroborates the complementary role of MRE in management of such patients.

Visceral and subcutaneous adipose tissue as markers of local and systemic inflammation: a comparison between celiac and obese patients using MRI

BACKGROUND

Celiac disease (CD) is a systemic inflammatory disease, which primarily affects the gastrointestinal tract. It has been recently demonstrated that adipose-tissue infiltration by proinflammatory immune cells causes a chronic low-grade inflammation in obese patients. Magnetic resonance imaging (MRI) has already proved to be useful in evaluation of inflammatory states. The aim of the present study was to determine whether alterations of visceral and subcutaneous adipose tissue, identified with MRI, could serve as markers of local and systemic inflammation in patients with CD.

METHODS

A pilot study was conducted comparing alterations in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in CD patients vs obese patients and healthy controls. Fifty patients were enrolled and assigned to one of the following groups: Group A: 11 active CD patients; Group B: 11 CD patients in remission; Group C: 16 obese patients; Group D: 12 healthy controls. A 3-T MRI unit was used and T2-weighted TSE images of VAT and SAT were obtained in specific regions of interest. Serum cytokine concentrations (TNF-α, IL-6, adiponectin, leptin, IL-2, IFN-γ) were determined.

RESULTS

There was a significant difference in VAT T2 relaxation time between Group A and B (p < 0.001), A and D (p < 0.01), B and C (p < 0.001). There was a statistically significant difference in SAT T2 relaxation time between Group A and B (p < 0.001), A and C (p < 0.05), A and D (p < 0.001), B and C (p < 0.01). In addition, VAT/SAT T2 relaxation time ratio showed a statistically significant difference between Group A and C (p < 0.05) and between Group B and C (p < 0.01). Only TNF-α and IL-6 significantly correlated with both VAT and VAT/SAT ratio in active CD.

CONCLUSIONS

MRI showed similar increased visceral inflammatory signals in patients with active CD and obese patients. However, subcutaneous inflammatory signals were higher in active CD than in all the other groups. These data show that there is a systemic inflammatory state in active CD, whereas chronic inflammation appears confined to VAT in obesity. These data were only partially confirmed by serological cytokine profiles, which showed less specificity than MRI.

An overview of magnetic resonance enterography for Crohn's disease

Magnetic resonance enterography (MRE) is a relatively new imaging modality that has shown promise for diagnosing, staging, and monitoring Crohn's disease (CD) and its complications while avoiding exposure to ionizing radiation. In addition to clinical implications, MRE has the potential to be used as an objective measure of disease activity for clinical trials. We provide the rationale for MRE, indications for its use, and an overview of the typical procedure and common findings for institutions who want to begin or refine the use of MRE for CD.

Noninflammatory conditions of the small bowel

Magnetic resonance (MR) imaging has been playing an evolving role in evaluating noninflammatory small-bowel conditions, such as tumors and malabsorption syndrome. MR imaging has shown to be superior to other diagnostic methods in identifying tumors of the small bowel. MR enterography and MR enteroclysis are both valid for studying noninflammatory conditions of the small intestine, although MR enteroclysis may be considered the modality of choice because of its accuracy in the diagnosis of small-bowel neoplasms. Intraluminal and extraluminal MR findings, combined with contrast-agent enhancement and functional information, help to make an accurate diagnosis and consequently to characterize small-bowel diseases.

Small Bowel Imaging: Clinical Applications of the Different Imaging Modalities—A Comprehensive Review

In the last years, MR and CT techniques have been optimized for small bowel imaging and are playing an increasing role in the evaluation of small bowel disorders. In comparison to traditional barium fluoroscopic examinations, spatial and temporal resolution is now much more improved partially thanks to modern bowel distending agents. However, there is a global interest in implementing techniques that either reduce or eliminate radiation exposure. This is especially important in patients with chronic diseases such as inflammatory bowel disease who may require multiple studies over a lifetime. Owing to the excellent soft tissue contrast, direct multiplanar imaging capabilities, new ultrafast breath-holding pulse sequences, lack of ionizing radiation, and availability of a variety of oral contrast agents, MR is well suited to play a critical role in the imaging of small bowel disorders.

Errors in the radiological evaluation of the alimentary tract: part II

Plain abdominal radiography and computed tomographic (CT) enteroclysis are 2 essential radiological investigations in the study of gastrointestinal tract. Errors in patient preparation, execution, and interpretation may lead to severe consequences in the diagnosis and thus in patient outcome. Abdominal radiography is one of the most frequently requested radiographic examinations, and has an established role in the assessment of the acute abdomen. CT enteroclysis has revolutionized the assessment of small-bowel pathology, especially in patients with inflammatory bowel. The purpose of this article is to describe the pitfalls in the execution and interpretation of plain abdominal film and CT enteroclysis.

MR imaging of the small bowel

Small-bowel radiology has undergone dramatic changes in the past 2 decades. Despite important recent advances in small-bowel endoscopy, radiologic imaging remains important for patients suspected of having or with established small-bowel disease. Cross-sectional imaging techniques (computed tomography and magnetic resonance [MR] imaging), used to investigate both extraluminal abnormalities and intraluminal changes, have gradually replaced barium contrast examinations, which are, however, still used to examine early mucosal disease. MR imaging techniques clearly highlight endoluminal, mural and extramural enteric details and provide vascular and functional information, thereby enhancing the diagnostic value of these techniques in small-bowel diseases. Two MR imaging based techniques are currently utilized: MR enteroclysis and MR enterography. In enteroclysis, enteric contrast material is administered through a nasoenteric tube, whereas in enterography, large volumes of enteric contrast material are administered orally. MR enteroclysis ensures consistently better luminal distention than does MR enterography in both the jejunum and the ileum and more accurately depicts endoluminal abnormalities and early disease, particularly at the level of the jejunal loops. Moreover, MR enteroclysis provides a high level of accuracy in the diagnosis and exclusion of small-bowel inflammatory and neoplastic diseases and can be used for the first radiologic evaluation, while MR enterography may effectively be used to follow up both Crohn disease patients without jejunal disease and in pediatric patients where nasogastric intubation might be a problem. MR enteroclysis may also reveal subtle transition points or an obstruction in the lower small bowel, which may escape detection when more routine methods, including enterography, are used. MR imaging offers detailed morphologic information and functional data of small-bowel diseases and provides reliable evidence of normalcy, thereby allowing the diagnosis of early or subtle structural abnormalities and guiding treatment and decisions in patient care.

Endoscopy and MR enteroclysis: equivalent tools in predicting clinical recurrence in patients with Crohn's disease after ileocolic resection

BACKGROUND

Ileocolonoscopy poses the gold standard in the evaluation of postoperative recurrence of Crohn's disease (CD) at the site of ileocolonic anastomosis. Magnetic resonance enteroclysis (MRE) on the other hand is a promising technique for small bowel imaging. The aim was to compare MRE and ileocolonoscopy for predicting clinical recurrence in CD patients who have undergone ileocolonic resection.

METHODS

We included 29 patients in the study. The median time since index operation was 35 months and between ileocolonoscopy and MRE was 3 days. Patients were followed up for a maximum of 2 years unless clinical recurrence occurred earlier. Endoscopic findings were evaluated on a 5-grade scale (i0-i4), whereas MRE findings on the neoterminal ileum and anastomosis were assessed according to a previously validated 4-grade scale MR score (MR0-MR3).

RESULTS

By classifying patients into subgroups of endoscopic severity of postoperative recurrence using as a threshold an endoscopic score of i3, we found that 10% of patients in the i0 to i2 group had a clinical recurrence during the 2-year follow-up period as compared to 52.6% of subjects with i3 to i4 (P = 0.043). The corresponding clinical exacerbation rates in the subgroups based on MRE severity assessment were 12.5% for MR0 to MR1 and 50% for MR2 to MR3 (P = 0.09).

CONCLUSIONS

Our data suggest that colonoscopy and MR enteroclysis are of similar value to predict the risk of clinical recurrence in postoperative patients with Crohn's disease.

Small bowel MRI enteroclysis or follow through: Which is optimal?

AIM: To determine if a nasojejunal tube (NJT) is required for optimal examination of enteroclysis and if patients can be examined only in the supine position.

METHODS: Data were collected from all patients undergoing small bowel (SB) magnetic resonance imaging (MRI) examination over a 32-mo period. Patients either underwent a magnetic resonance (MR) follow-through (MRFT) or a MR enteroclysis (MRE) in the supine position. The quality of proximal and distal SB distension as well as the presence of motion artefact and image quality were assessed by 2 radiologists.

RESULTS: One hundred and fourteen MR studies were undertaken (MRFT-49, MRE-65) in 108 patients in the supine position only. Image artefact was more frequent in MRE than in MRFT (29.2% vs 18.4%), but was not statistically significant (P = 0.30). Adequate distension of the distal SB was obtained in 97.8% of MRFT examinations and in 95.4% of MRE examinations, respectively. Proximal SB distension was, however, less frequently optimal in MRFT than in MRE (P = 0.0036), particularly in patients over the age of 50 years (P = 0.0099). Image quality was good in all examinations.

CONCLUSION: All patients could be successfully imaged in the supine position. MRE and MRFT are equivalent for distal SB distension and artefact effects. Proximal SB distension is frequently less optimal in MRFT than in MRE. MRE is, therefore, the preferred MR examination method of the SB.

Radiological features of Meckel's diverticulum and its complications

Meckel's diverticulum is the most common congenital abnormality of the small bowel. The majority of patients with this anomaly will remain asymptomatic; however, several complications may occur, including obstruction, intussusception, perforation, diverticulitis, and gastrointestinal haemorrhage. These complications may produce a variety of different clinical features and radiological appearances. The purpose of this article is to review the potential imaging manifestations of Meckel's diverticulum and its complications and discuss the advantages and disadvantages of the imaging techniques available.

Computed tomography enteroclysis in the diagnosis of intestinal diseases

The role of computed tomography (CT) enteroclysis in the imaging of small bowel diseases is expanded with recent technological advances in multidetector CT system. Computed tomography enteroclysis is the examination of choice for patients with symptoms of intermittent small bowel obstruction, especially when there is a history of prior complex abdominal surgery, abdominal tumor, radiation therapy, and also in high grade obstructions with suspicion of extraintestinal internal fistula. Computed tomography enteroclysis is becoming the first-line modality for the evaluation of advanced and complicated small bowel Crohn disease. Computed tomography enteroclysis can also become an important complementary imaging technique to capsule endoscopy in the assessment of small bowel neoplasms and occult gastrointestinal hemorrhage. In this study, the technique and clinical applications of CT enteroclysis are reviewed; its advantages and limitations compared with the other imaging techniques and capsule endoscopy are discussed.

MRI of the small bowel with oral contrast or nasojejunal intubation in Crohn's disease: randomized comparison of patient acceptance

OBJECTIVE

Magnetic resonance imaging of the small bowel with an oral contrast (MRI per os) is believed to generate fewer adverse symptoms compared with installation of the contrast in a nasojejunal catheter (MRE). However, there is very little evidence to support this assumption. The aim of this study was to evaluate the compliance of patients examined with both of these MRI methods.

MATERIAL AND METHODS

Patients with suspected or known Crohn's disease referred for MRI of the small bowel underwent both MRI per os and MRE within 7 days. A questionnaire was answered immediately and 24 h after the procedure. Adverse symptoms were graded on a visual analogue scale (VAS). Responses were compared with paired and independent sample t-tests and signed-rank tests. Correlation of each symptom to the overall discomfort was evaluated with Spearman's correlation coefficient.

RESULTS

Thirty-eight patients (18 F, 20 M) were included in the analysis. Abdominal pain and discomfort were lower with MRI per os than with MRE (mean VAS pain score immediately after: 10 mm and 33 mm, respectively, p < 0.001; mean VAS discomfort score 24 h after: 18 mm and 62 mm, respectively, p < 0.001). Nausea and abdominal pain were correlated with overall discomfort after MRI per os (r = 0.56 for both, p < 0.001). No symptoms were significantly correlated with discomfort experienced with MRE. More patients accepted repeat MRI per os examination (n = 36) than MRE (n = 22, p = 0.001).

CONCLUSION

Patients preferred and experienced less abdominal pain and discomfort with MRI per os than with MRE.

Double-balloon enteroscopy versus magnetic resonance enteroclysis in diagnosing suspected small-bowel Crohn's disease: results of a pilot study

OBJECTIVE

Small-bowel manifestations are common complications in Crohn's disease (CD) but can often be underestimated because of diagnostic limitations. Double-balloon enteroscopy (DBE) is a new endoscopic method that provides complete visualization and biopsy sampling of the small bowel with potential implications for diagnosis and therapy. The purpose of this study was to compare the diagnostic yield of DBE and magnetic resonance enteroclysis (MRE) in patients suspected of having small-bowel CD.

MATERIAL AND METHODS

Ten patients were consecutively selected and included in the study. In all patients a DBE of the small bowel was performed, the endoscopist being unaware of the radiological findings. Evaluation criteria included the presence of pathology, localization, degree, and extension of affection according to predefined morphologic criteria. Samples for histopathological investigation were taken in all patients with abnormal mucosa.

RESULTS

In 50% of the patients (5 out of 10) with suspected small-bowel CD, DBE revealed pathological results. Here, in four patients, CD was verified histologically. A new diagnosis had to be established in one patient diagnosed for malignant lymphoma. The medical management had to change in five patients. In two patients, both DBE and MRE showed no pathological results; in three patients, superficial lesions were identified by MRE, whereas DBE was normal.

CONCLUSIONS

In selected patients with suspected small-bowel lesions, DBE is a promising tool in the diagnostic work-up and provides the advantage of biopsy sampling. In contrast, non-invasive MRE delivers excellent information about extraluminal pathology associated with CD. Both MRE and DBE have the potential to become diagnostic standards that complement each other in patients with suspected complex small-bowel CD.

Internal fistulas in Crohn disease: magnetic resonance enteroclysis

Internal fistulas (IFs) and abscesses are the most common complications of Crohn disease (CD). To reliably diagnose and clearly distinguish inflammatory or fibrostenotic manifestations of CD from its complications is of paramount importance to appropriately guide therapeutic decisions. Magnetic resonance enteroclysis (MRE), a recently introduced technique for small bowel imaging, has proved a high efficacy in the depiction of luminal and extraluminal manifestations of CD and holds great promise as a powerful diagnostic tool in the comprehensive diagnostic workup of this disease. As of yet, the characteristic imaging appearance of IFs on MRE has not been described in detail. This article reviews the performance of conventional imaging techniques and the current potential of MRE in the depiction of IFs in CD. Typical imaging morphology and characteristic imaging findings of IFs on MRE are described in detail and a newly defined and highly indicative imaging finding, the "star-sign," is presented and discussed.

Comparison of MR enteroclysis with MR enterography and conventional enteroclysis in patients with Crohn's disease

To prospectively compare the diagnostic accuracy of MR enteroclysis with duodenal intubation with MRI after drinking oral contrast agent only (MR enterography) with conventional enteroclysis (conv-E) as reference standard in patients with Crohn's disease. Forty consecutive patients (22 males and 18 females; mean age 36; range 16-74 years) with proven Crohn's disease underwent conv-E and MR imaging. Twenty-two patients underwent MR enteroclysis with intubation (MRE) and 18 underwent MR-enterography (MR per OS). Two radiologists reached a consensus about the following imaging findings: luminal distension and visualization of superficial mucosal, mural and mesenteric abnormalities. Standard descriptive statistics and a Wilcoxon rank sum test were used. Statistical significance was inferred at P < 0.05. There was no significant difference in the adequacy of luminal distention between the MRE and conv-E (P = 0.08), and both were statistically superior in comparison to MR per OS in the distension of the jejunum (P < 0.01) and less significant at the ileum and terminal ileum levels (P < 0.05). MRE and conv-E were comparable for the accuracy of superficial mucosal abnormalities; meanwhile conv-E compared with MR per OS was statistically superior (P < 0.01). MRE compared with MR per OS was statistically better when visualizing superficial abnormalities (P < 0.01). No statistically significant differences were found in assessing the diagnostic efficacy between MR examinations for the depiction of mural stenosis (P = 0.105) and fistulae (P = 0.67). The number of detected mesenteric findings was significantly higher with both MRE and MR per OS compared to conv-E (P < 0.01). MRE can serve as the diagnostic procedure for initially evaluating patients suspected of having Crohn's disease. MR per OS may have a role in patients that refuse or have failed intubation and also for follow-up.

Jejunum abnormalities at MR enteroclysis

OBJECTIVE

MR enteroclysis has become an important tool to visualize the complete small bowel wall and extramural structures. In many centers, this technique is rapidly becoming the first-line technique for small bowel visualization. MR enteroclysis yields a diagnosis of thickened jejunal loops in some patients. In this paper, we describe an MR enteroclysis protocol and review the literature on jejunum abnormalities with several sample cases.

CONCLUSION

Jejunum abnormalities are not uncommon. These abnormalities can be self-limiting, but some patients suffer from infectious and other pathologic conditions of the small bowel necessitating intervention.

A prospective randomized comparison between two MRI studies of the small bowel in Crohn's disease, the oral contrast method and MR enteroclysis

The aim was to compare bowel distension and diagnostic properties of magnetic resonance imaging of the small bowel with oral contrast (MRI per OS) with magnetic resonance enteroclysis (MRE). Forty patients with suspected Crohn's disease (CD) were examined with both MRI methods. MRI per OS was performed with a 6% mannitol solution and MRE with nasojejunal intubation and a polyethylenglycol solution. MRI protocol consisted of balanced fast field echo (B-FFE), T2 and T1 sequences with and without gadolinium. Two experienced radiologists individually evaluated bowel distension and pathological findings including wall thickness (BWT), contrast enhancement (BWE), ulcer (BWU), stenosis (BWS) and edema (EDM). The diameter of the small bowel was smaller with MRI per OS than with MRE (difference jejunum: 0.55 cm, p < 0.001; ileum: 0.35 cm, p < 0.001, terminal ileum: 0.09 cm, p = 0.08). However, CD was diagnosed with high diagnostic accuracy (sensitivity, specificity, positive and negative predictive values: MRI per OS 88%, 89%, 89%, 89%; MRE 88%, 84%, 82%, 89%) and inter-observer agreement (MRI per OS k = 0.95; MRE k = 1). In conclusion, bowel distension was inferior in MRI per OS compared to MRE. However, both methods diagnosed CD with a high diagnostic accuracy and reproducibility.

Crohn disease of the small bowel: MR enteroclysis versus conventional enteroclysis

Enteroclysis has been suggested as the technique of choice for the evaluation of Crohn disease of the small intestine. Adequate distention of the entire small bowel with barium suspension allows the radiologic demonstration of mucosal abnormalities and provides functional information by defining distensibility or fixation of the small bowel loops. The principal disadvantage of conventional enteroclysis is the limited indirect information on the state of the bowel wall and extramural extension of Crohn disease, and its effectiveness may be hindered owing to overlapping bowel loops. Moreover, the radiation dose administered to patients, mostly at a young age, should be considered. Magnetic resonance (MR) enteroclysis is an emerging technique for small bowel imaging and was introduced to overcome the limitations of conventional enteroclysis and MR cross-sectional imaging by combining the advantages of both into one technique. MR enteroclysis has the potential to change how the small bowel is assessed because of the functional information, soft tissue contrast, direct multiplanar imaging capabilities, and lack of ionizing radiation.

Clinical features of patients with negative results from traditional diagnostic work-up and Crohn's disease findings from capsule endoscopy

INTRODUCTION

Capsule endoscopy (CE) can detect Crohn's disease in patients with suggestive symptoms but with negative results from the traditional diagnostic work-up (ileocolonoscopy and small bowel follow-through). The objective of this study was to determine which clinical features predict the diagnosis of Crohn's disease by CE in this subgroup of patients.

MATERIAL AND METHODS

Twenty-three patients (7 men, 16 women; mean age: 40+/-15 y) with negative results from conventional imaging techniques were prospectively included in the study because of suspicion of Crohn's disease (long-standing abdominal pain and/or diarrhea and at least one of the following symptoms: anemia, weight loss, long-standing fever, perianal disease, extraintestinal manifestations typical of inflammatory bowel disease, elevated inflammatory parameters, or family history of inflammatory bowel disease).

RESULTS

CE diagnosed Crohn's disease in 6 patients (26%). Crohn's disease diagnosis was more frequent in patients with a combination of anemia and elevated inflammatory parameters than in patients without this combination (57% vs. 12.5%; P=0.04). The only statistically significant association between an inflammatory parameter and Crohn's disease was an increased platelet count.

CONCLUSIONS

CE is a useful tool for the diagnosis of subtle small bowel Crohn's disease. The diagnostic yield of CE in patients with suspicion of Crohn's disease but negative results from the traditional diagnostic work-up is significantly higher in patients with anemia and increased platelet count than in patients without this combination of clinical features.

Assessment of Crohn's disease in the small bowel: Prospective comparison of magnetic resonance enteroclysis with conventional enteroclysis

Our objective was to assess the diagnostic value of magnetic resonance enteroclysis (MRE) compared with conventional enteroclysis (CE) in patients with Crohn's disease. A secondary objective was to evaluate the diagnostic accuracy of each different MR sequence. Sixty-six consecutive patients with known Crohn's disease underwent MRE and CE. Fast imaging employing steady-state acquisition (FIESTA), single-shot fast spin-echo (ssFSE), and contrast-enhanced T1-weighted sequences were assessed by two radiologists who reached a consensus about the following findings: visualization of wall ulcers, pseudopolyps, fistulae, mural stenosis, and mesenteric abnormalities. Standard descriptive statistics and the McNemar test were used. The sensitivity, specificity and accuracy of MRE were 90-87% and 83% for the depiction of parietal ulcers, 84%-88% and 86% for pseudopolyps, 100-94% and 96% for mural stenosis, 93-100% and 94% for fistulae. The number of detected extraluminal findings was significantly higher with MRE (P < 0.01). The accuracy of FIESTA sequence was statistically higher in the depiction of wall ulcers and fistulae than that of three-dimensional fast spoiled gradient echo (3D-FSPGR) (P < 0.01) and ssFSE (P < 0.05) sequences. Contrast-enhanced 3D-FSPGR was superior for mural stenosis visualization compared to ssFSE (P < 0.05) and FIESTA (P < 0.05). MRE correlates accurately with CE in the detection of superficial and transmural abnormalities and has the advantage of assessing the mesenteric manifestations.

Multislice CT enteroclysis: technique and clinical applications

Computed tomography (CT) enteroclysis was introduced to overcome the individual deficiencies of barium enteroclysis and abdominal CT. The use of multislice CT technology has made the procedure a feasible extension of the intubation infusion method of small bowel examination. This review is an update of the technique and clinical application of CT enteroclysis with illustrations.

Sonoenteroclysis: a new technique for the diagnosis of small bowel diseases

BACKGROUND

Radiologic evaluation of small bowel is usually done by barium examination, which involves considerable radiation exposure. A new sonographic method, sonoenteroclysis, is a promising technique for diagnosing small intestinal disorders. In this study the applicability, performance, and diagnostic yield of sonoenteroclysis were assessed and the results of this novel method were compared with those of barium enteroclysis.

METHODS

Forty-five consecutive patients with suspected small bowel disorder were studied. All patients underwent abdominal ultrasound before and after infusion of an isotonic nonabsorbable electrolyte solution containing polyethylene glycol through a nasojejunal tube (modified Billbao Dotter tube), and images at various levels were obtained. Small bowel wall thickness, luminal narrowing, intestinal dilatation, peristalsis, and extraintestinal complications were noted. It was followed by barium enteroclysis and findings were recorded. Findings of sonoenteroclysis were compared with those of barium enteroclysis.

RESULTS

Satisfactory distention of the intestinal lumen was obtained with sequential visualization of jejunoileal loops in 34.4 +/- 18.4 min. Of 45 patients, 10 showed normal small bowel on sonoenteroclysis and barium enteroclysis. These 10 patients served as controls. Sonoenteroclysis displayed normal diameters smaller than 3.0 and 2.0 cm for the jejunum and ileum, respectively. Bowel wall thickness was 1.7 to 3.0 mm and all five layers of bowel wall could be well appreciated. Valvulae conniventes were clearly visualized with a fold thickness between 1.4 and 2.0 mm. The remaining 35 patients showed abnormalities in the form of strictures, matted bowel loops, dilated loops, thickened folds, deformed ileocecal junction, mass lesions, etc., on sonoenteroclysis and barium enteroclysis. In addition, sonoenteroclysis showed thickened bowel wall with loss of stratification. Extraintestinal findings such as enlarged lymph nodes and ascites were also disclosed at the time of sonography. These were diagnosed subsequently as cases of tuberculosis (n = 23), celiac disease (n = 6), adenocarcinoma (n = 2), leiomyoma (n = 2), Immunoproliferative small intestinal disease (n = 1), and segmental enteritis (n = 1).

CONCLUSIONS

The diagnostic accuracy of sonoenteroclysis for detecting small bowel lesions is comparable to that of barium enteroclysis. This new, widely available, inexpensive, and undemanding technique can be used as an initial investigation in the evaluation of patients with small bowel disorders.

Peroral CT Enterography with Lactulose Solution: Preliminary Observations

OBJECTIVE

The objective of our study was to evaluate lactulose solution as a new oral contrast agent with the use of peroral CT enterography to determine the adequacy of luminal distention and conspicuity of the bowel wall.

CONCLUSION

Peroral CT enterography performed with lactulose solution is a simple and noninvasive method of evaluating the small bowel by obtaining good distention. It can also be used at routine abdominal examinations as a negative contrast agent instead of iodinated oral contrast medium, especially for CT angiography.

Comprehensive Magnetic Resonance Imaging of the Small and Large Bowel Using Intraluminal Dual Contrast Technique With Iron Oxide Solution and Water in Magnetic Resonance Enteroclysis

OBJECTIVE

The objective of this study was to improve delineation of small and large bowel (SB, LB) anatomy and pathology with postoperative or complex multisegmental inflammatory changes using dual-contrast-technique (DCT) for magnetic resonance enteroclysis (MRE) with luminal contrast media of opposed signal characteristics.

MATERIALS AND METHODS

Sixty patients underwent MRE with iron oxide-based negative contrast in the SB. Thirty patients received additional rectal instillation of water for positive contrast (DCT). Two observers evaluated the degree of distention and the ease of identification of bowel anatomy and pathologies (none n=22, stenosis n=16, abscess n=4, fistulae n=5, postoperative changes and adhesions n=13) using a 4-point scale. Mann-Whitney U-test and kappa statistics were applied.

RESULTS

LB and the terminal ileum were significantly better distended and identified with DCT (P<or=0.0001; P=0.034). Interobserver agreement improved with DCT for all pathologies except for "prestenotic dilatation."

CONCLUSIONS

Comprehensive MR imaging of SB and LB with DCT improves the identification of modified anatomy and most pathologies in inflammatory and postsurgical bowel.

MR enteroclysis: imaging technique of choice in diagnosis of small bowel diseases

MR enteroclysis is becoming a very important imaging modality in the workup and follow-up of small bowel diseases. The technique has many advantages, including the absence of ionizing radiation, ability to control luminal distension, superior tissue characterization, multiplanar capabilities, and mural and extramural visualization. These capabilities can be obtained with a simple protocol showing excellent agreement with conventional enteroclysis. In 29 (18 with new or known Crohn's disease) of the 50 patients pathology was detected, with a very good clinical correlation. In 14 patients MR enteroclysis data altered the therapeutic strategy. This contributes to the acceptance of this modality as a primary tool in small bowel diseases.

Small Bowel Adenocarcinoma: A Rare but Aggressive Disease

Unlike the colon and rectum, the small intestine is associated with a very low rate of tumor occurrence. Adenocarcinomas represent the most frequent of these rare digestive tumors and are often fatal as a result of tardy diagnosis. Regardless of the stage, surgery usually remains the cornerstone of small bowel adenocarcinoma therapy. Because of the rarity of the disease, very few significant clinical trials have identified any efficient nonsurgical treatment; however, recent data indicate these tumors might be sensitive to chemotherapy alone or in association with radiation therapy. Conversely, a great deal of progress has been achieved in diagnosis of the tumor, whether by adaptation of existing techniques or development of new ones. We reviewed the clinical aspects of this rare but aggressive disease, focusing on new diagnostic procedures as well as on recent advances in their therapeutic management.

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.

MRI for small bowel diseases

The role of radiologic studies has been well established in the diagnosis and management of patients with small bowel diseases. While small bowel follow-through examination or enteroclysis is widely accepted as the primary imaging method for small bowel investigation, additional cross-sectional imaging studies are often required for an accurate diagnosis and the precise evaluation of the extraluminal disease. Since fast magnetic resonance imaging (MRI) sequences have become available, there is increasing interest in the use of MRI for small bowel evaluation, attributed to its inherent advantages such as the lack of radiation exposure, excellent soft tissue contrast, and direct multiplanar capabilities. In this article, we review the current techniques, clinical applications, and limitations of MRI for the evaluation of patients with small bowel diseases.

CT diagnosis of small bowel obstruction: scanning technique, interpretation and role in the diagnosis

Intestinal obstruction is a relatively common condition with diagnosis based on the clinical signs, patient history, and radiographical findings. Once suspected, its presence should be determined and if present, the site and cause of obstruction, and presence of strangulation should be assessed for the appropriate patient management. With the recent technological developments, the role of computed tomography (CT) in the diagnosis of bowel obstruction has expanded. The examination should be performed with intravenous contrast administration and thinner sections and multi-planner image reformation are recommended to evaluate a site of particular interest. CT is reported to have a sensitivity refer to detection of a small bowel obstruction at over 90% for complete or high-grade obstruction and to disclose causes of obstruction in 70% to 95% of cases. CT also provides characteristic findings indicating the presence of closed-loop obstruction and intestinal ischemia, which leads to appropriate and timely management for these emergent cases.