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 iraaged 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.

Small intestine contrast ultrasonography vs computed tomography enteroclysis for assessing ileal Crohn's disease

AIM:To compare computed tomography enteroclysis(CTE) vs small intestine contrast ultrasonography(SICUS) for assessing small bowel lesions in Crohn's disease(CD),when using surgical pathology as gold standard.METHODS:From January 2007 to July 2008,15 eligible patients undergoing elective resection of the distal ileum and coecum(or right colon) were prospectively enrolled.All patients were under follow-up.The study population included 6 males and 9 females,with a median age of 44 years(range:18-80 years).Inclusion criteria:(1) certain diagnosis of small bowel requiring elective ileo-colonic resection;(2) age between 18-80 years;(3) elective surgery in our Surgical Unit;and(4) written informed consent.SICUS and CTE were performed ≤ 3 mo before surgery,followed by surgical pathology.The following small bowel lesions were blindly reported by one sonologist,radiologist,surgeon and histolopathologist:disease site,extent,strictures,abscesses,fistulae,small bowel dilation.Comparison between findings at SICUS,CTE,surgical specimens and histological examination was made by assessing the specificity,sensitivity and accuracy of each technique,when using surgical findings as gold standard.RESULTS:Among the 15 patients enrolled,CTE was not feasible in 2 patients,due to urgent surgery in one patients and to low compliance in the second patient,refusing to perform CTE due to the discomfort related to the naso-jejunal tube.The analysis for comparing CTE vs SICUS findings was therefore performed in 13 out of the 15 CD patients enrolled.Differently from CTE,SICUS was feasible in all the 15 patients enrolled.No complications were observed when using SICUS or CTE.Surgical pathology findings in the tested population included:small bowel stricture in 13 patients,small bowel dilation above ileal stricture in 10 patients,abdominal abscesses in 2 patients,enteric fistulae in 5 patients,lymphnodes enlargement(> 1 cm) in 7 patients and mesenteric enlargement in 9 patients.In order to compare findings by using SICUS,CTE,histology and surgery,characteristics of the small bowel lesions observed in CD each patient were blindly reported in the same form by one gastroenterologistsonologist,radiologist,surgeon and anatomopathologist.At surgery,lesions related to CD were detected in the distal ileum in all 13 patients,also visualized by both SICUS and CTE in all 13 patients.Ileal lesions > 10 cm length were detected at surgery in all the 13 CD patients,confirmed by SICUS and CTE in the same 12 out of the 13 patients.When using surgical findings as a gold standard,SICUS and CTE showed the exactly same sensitivity,specificity and accuracy for detecting the presence of small bowel fistulae(accuracy 77% for both) and abscesses(accuracy 85% for both).In the tested CD population,SICUS and CTE were also quite comparable in terms of accuracy for detecting the presence of small bowel strictures(92% vs 100%),small bowel fistulae(77% for both) and small bowel dilation(85% vs 82%).CONCLUSION:In our study population,CTE and the non-invasive and radiation-free SICUS showed a comparable high accuracy for assessing small bowel lesions in CD.

Sonography of the small intestine

In the last two decades, there has been substantial development in the diagnostic possibilities for examining the small intestine. Compared with computerized tomography, magnetic resonance imaging, capsule endoscopy and double-balloon endoscopy, ultrasonography has the advantage of being cheap, portable, flexible and user-and patient-friendly, while at the same time providing the clinician with image data of high temporal and spatial resolution. The method has limitations with penetration in obesity and with intestinal air impairing image quality. The flexibility ultrasonography offers the examiner also implies that a systematic approach during scanning is needed. This paper reviews the basic scanning techniques and new modalities such as contrast-enhanced ultrasound, elastography, strain rate imaging, hydrosonography, allergosonography, endoscopic sonography and nutritional imaging, and the literature on disease-specific findings in the small intestine. Some of these methods have shown clinical benefit, while others are under research and development to establish their role in the diagnostic repertoire. However, along with improved overall image quality of new ultrasound scanners, these methodshave enabled more anatomical and physiological changes in the small intestine to be observed. Accordingly, ultrasound of the small intestine is an attractive clinical tool to study patients with a range of diseases.

New progress in CT and MRI examination and diagnosis of small intestinal tumors

Precise examination and diagnosis of small intestinal tumors is difficult because of the curved course and overlapping canal of the small intestine. Traditional technology for intestinal canal examination and endoscopy cannot exhibit the intestinal wall and extra-luminal structure well. With the development and advancement of multi-slice spiral computed tomography and magnetic resonance imaging (MRI), computed tomography enteroclysis (CTE) and magnetic resonance enteroclysis (MRE) are widely used in the examination and diagnosis of small intestinal tumors. CTE and MRE, with three-dimensional imaging capabilities and excellent soft-tissue contrast, can analyze the abnormalities of peripheral intestinal structure as well as the tunica mucosa. In addition, these two technologies can clearly reveal the localization, appearance, degree of mesenteric infiltration and remote tumor metastasis, which increases our cognition of the imaging diagnosis for intestinal tumors. Here we review recent progress in imaging (CT and MRI) examination and diagnosis of small intestinal tumors.