Intubation routes for enteroclysis

Individualized small bowel preparation for computed tomography enterography: A prospective randomized controlled trial

BACKGROUND AND AIM

The study aims to evaluate the feasibility of body mass index (BMI)-based individualized small bowel preparation for computed tomography enterography (CTE).

METHODS

In this prospective randomized controlled study, patients undergoing CTE were randomly assigned to the individualized group or standardized group. Those in individualized group were given different volumes of mannitol solution based on BMI (1000 mL for patients with BMI < 18.5 kg/m2 , 1500 mL for patients with 18.5 kg/m2  ≤ BMI < 25 kg/m2 and 2000 mL for patients with BMI ≥ 25 kg/m2 ) while patients in the standardized group were all asked to consume 1500-mL mannitol solution. CTE images were reviewed by two experienced radiologists blindly. Each segment of the small bowel was assessed for small bowel image quality and disease detection rates. Patients were invited to record a diary regarding adverse events and acceptance.

RESULTS

A total of 203 patients were enrolled and randomly divided into two groups. For patients with BMI < 18.5 kg/m2 , 1000-mL mannitol solution permitted a significantly lower rate of flatulence (P = 0.045) and defecating frequency (P = 0.011) as well as higher acceptance score (P = 0.015), but did not affect bowel image quality and diseases detection compared with conventional dosage. For patients with BMI ≥ 25 kg/m2 , 2000-mL mannitol solution provided better overall image quality (P = 0.033) but comparable rates of adverse events and patients' acceptance compared with conventional dosage.

CONCLUSIONS

Individualized bowel preparation could achieve both satisfactory image quality and patients' acceptance thus might be an acceptable alternative in CTE.

MRI scoring system including dynamic motility evaluation in assessing the activity of Crohn's disease of the terminal ileum

RATIONALE AND OBJECTIVES

We sought to investigate the value of a MRI scoring system including dynamic motility evaluation in the assessment of small bowel Crohn's disease activity.

MATERIALS AND METHODS

From March 2005 to December 2006, 52 patients with suspected Crohn's disease onset or relapse underwent MRI on a 1.5-T magnet. Bowel distention was achieved orally assuming a mean of 1.6 L of a polyethyleneglycol (PEG) preparation. Per-patient assessment of disease activity was based on a scoring system including evaluation of morphology and motility of the small bowel and perivisceral structures (true-FISP, cine-true-FISP, and HASTE T2W sequences) and dynamic assessment of parietal contrast enhancement (FLASH T1W sequence). Patients were included in three categories, using endoscopic biopsy as the standard reference: no activity/quiescent disease, mild activity, or moderate-to-severe activity. Patients without terminal ileum involvement were excluded from data analysis.

RESULTS

MRI allowed a detailed and panoramic evaluation of the small bowel in all subjects examined. MRI properly assessed 14 of 16 (87.5%) cases of no activity/quiescent disease, 12 of 14 (85.7%) cases of mild activity, and 15 of 15 (100%) cases of severe activity. Overall, activity score led to a per-patient misdiagnosis of disease activity in a nonsignificant proportion of subjects (4 of 45; 8.8%) (P > .05), determining two false-positive and two false-negative results of mild disease activity. Sensitivity, specificity, PPV, NPV, and overall accuracy in assessing disease activity were 93.1%, 87.5%, 93.1%, 87.5%, and 91.1%, respectively.

CONCLUSION

Accurate assessment of Crohn's disease activity is achieved by using an activity score providing an overall interpretation of MRI findings.

Hydro-MRI of the small bowel: effect of contrast volume, timing of contrast administration, and data acquisition on bowel distention

OBJECTIVE

The purpose of this study was to assess oral contrast agents, volumes of the agents, and time points of data acquisition in regard to small-bowel distention and patient acceptance.

SUBJECTS AND METHODS

Six healthy volunteers underwent imaging on 16 different days. Four volumes (450, 900, 1,350, and 1,800 mL) of each of the four contrast compounds (0.2% locust bean gum plus 2.5% mannitol, VoLumen containing 2.0% sorbitol, VoLumen containing 1.4% sorbitol, and tap water) were used. Two-dimensional true fast imaging with steady-state free precession data sets were acquired at 5-minute intervals after contrast ingestion. Distention values for small-bowel segments (duodenum, proximal and distal jejunum, ileum) and occurrence of side effects were documented.

RESULTS

Analysis of bowel distention revealed significantly greater distention for all carbohydrate sugar alcohol-containing solutions compared with water but no significant difference among the three contrast agents. Sufficient duodenal distention was achieved with 900 mL of any of the contrast agents, but imaging had to be performed soon after ingestion. For MRI of the distal jejunum and ileum, a volume of 1,350 mL is preferable, and the time point of data acquisition plays a minor role. Ingestion of 1,800 mL of the carbohydrate sugar alcohol solutions led to a significantly higher rate of side effects such as abdominal cramps than did ingestion of smaller volumes.

CONCLUSION

The data indicate that sufficient contrast consumption and optimal timing of data acquisition are essential to distention of the small bowel. Oral contrast agent protocols should be adapted to the bowel region in question.

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.

Optimization of oral contrast agents for MR imaging of the small bowel

Effect on small-bowel distention of additives to water as contrast agents for magnetic resonance (MR) imaging was assessed. Oral contrast agents included water and water in combination with mannitol, a bulk fiber laxative, locust bean gum, and a combination of mannitol and locust bean gum. Filling of the small bowel was quantified on coronal images obtained with two-dimensional true fast imaging with steady-state precession sequence; bowel diameters were measured. Ingestion of water with locust bean gum and mannitol provided the best distention of the small bowel. MR imaging of the small bowel with oral administration of water can be improved with addition of osmotic and nonosmotic substances that lead to decreased water resorption.

Technical refinements in enteroclysis

As the primary method of investigating the small bowel, enteroclysis remains a technique in evolution. Technical refinements have made the examination faster to perform, better tolerated by patients, and easier to interpret. More recently, its essential principle of volume challenge has been combined with the tremendous advantage of CT cross-sectional imaging with multiplanar reformatting to give rise to the exciting new techniques of CT enteroclysis and MR enteroclysis (see separate reviews in this issue). Through improvements in methodology and advancements in technology, the future of enteroclysis looks bright indeed.

Technical report: intubation fluoroscopy times using a new enteroclysis tube

Initial experience with a new 10 F gauge version of the Nolan enteroclysis tube is reported. The mean intubation fluoroscopy time in 80 patients was 1.53 min. The more flexible smaller gauge tube is ideal for rapid duodenal intubation via the nasal route.

Enteroclysis--the influence of tube design

The performance of three 10F enteroclysis tubes with different tip designs (E. Merck Ltd) was assessed using double-contrast, gravity infusion enteroclysis, with methylcellulose solution as negative contrast. Intubation times, screening times, patient tolerability and examination quality were compared. The results show that a streamlined tip design facilitated passage through the nose. None of the tubes provided consistently reliable results due to inadequate flow rates. The Corsafe tube transmits a higher flow rate of methylcellulose and produced satisfactory examinations more frequently. Mechanically assisted infusion of methylcellulose is recommended when using 10F enteroclysis tubes.

The small bowel enema made easy

The small bowel enema (barium infusion, enteroclysis) is a valuable radiological procedure that is easy to use and gives consistently good results. The technique is described and important aspects of the examination are discussed.