Feeding management before gastrointestinal studies in pigs.

Pigs are used to model humans in gastrointestinal (GI) studies because of their comparable size, physiology and behaviour: both are monogastric omnivores. A porcine surgical model for testing novel, tethered ultrasound capsule endoscopes (USCE) requires a clean, motile small intestine. Recommendations for human GI tract preparation before the mechanically similar process of video capsule endoscopy describe using oral purgatives, while high-carbohydrate drinks are recommended before colorectal surgery. Reports of the GI preparation of pigs exist but lack technical details, that is, administration, efficacy and side effects. This report details feeding a high-energy liquid diet to 11 female pigs undergoing surgery and USCE which was readily accepted and easily administered, and which produced a clean, motile small intestine and caused no detectable physiological/behavioural abnormalities.

High-resolution microendoscope imaging of inverted papilloma and normal sinonasal mucosa: evaluation of interobserver concordance.

BACKGROUND: High-resolution microendoscopy (HRME) enables real-time imaging of epithelial tissue. The utility of this novel imaging modality for inverted papilloma has not been previously described. This study examines the ability of otolaryngologists to differentiate between images of inverted papilloma and normal sinonasal mucosa obtained with a HRME. METHODS: Inverted papilloma and normal sinonasal mucosa specimens were stained with a contrast agent, proflavine. HRME images were subsequently captured. Histopathological diagnosis was obtained for each sample. Quality-controlled images were used to assemble a training set. After reviewing the training images, 6 otolaryngologists without prior HRME experience reviewed and classified test images. RESULTS: Five samples of inverted papilloma and 2 normal sinonasal mucosa samples were collected. Four representative images from each specimen were used for the 28-image test set. The mean accuracy among all reviewers was 89.9% (95% confidence interval [CI], 84.3% to 94.0%). The sensitivity to correctly identify inverted papilloma was 86.7% (95% CI, 79.2% to 92.2%), and the specificity was 92.9% (95% CI, 89.0% to 100.0%). The Fleiss kappa interrater reliability score was 0.80 (95% CI, 0.70 to 0.89). CONCLUSION: Inverted papilloma and normal sinonasal mucosa have distinct HRME imaging characteristics. Otolaryngologists can be successfully trained to distinguish between inverted papilloma and normal sinonasal mucosa. HRME is a feasible tool for identification of inverted papilloma. By conducting future in vivo trials, HRME potentially may enable real-time surgical margin determination during surgical excision of inverted papilloma.

Capsule endoscopy in a network cooperation: assessment of the experience in 822 patients.

INTRODUCTION: Capsule endoscopy (CE) is firmly established as a standard procedure in the diagnostic algorithm of occult or obscure gastrointestinal bleeding and Crohn's disease. Despite its excellent diagnostic yield, missing expertise, reading time and financial expenditure limit an area-wide availability. A multicentric cooperation might compensate these disadvantages. METHODS: CE device was bought by a central hospital (CH). Requested equipment is transported to the network partner (NP) and the procedure performed at the spot in personal responsibility. Video reading is exclusively done in the CH. RESULTS: Within 10 years, 822 CE (438 m., 384 f.; 63 ± 17 (13-92) years) were performed by 18 cooperating gastroenterological departments. 587/822 (71%) CE were done at NP, 235/822 (29%) in the CH. Between 2002 (n = 39) and 2011 (n = 123) the annual number of CE increased threefold. 95% of the capital investment in each cooperating hospital could be avoided by sharing one workstation within the network. Leading indication for CE was suspected mid-GI-bleeding (80%). Mean latencies between requested date and actual examination were 0 and between equipment's return and report 2 days. 45/191(24%) flexible enteroscopies performed in the CH followed CE findings from NP. DISCUSSION: Our 10 years experience show that mobile use of CE is feasible providing quality parameters similar to a single center solution, increases the number of CE investigations, therefore, improves reading expertise and enables both an area-wide and economic offer for this technique. Additionally, patients with the need for invasive enteroscopy are identified and attracted to that NP who provides an invasive SB endocopy device.

The use of small bowel capsule endoscopy in iron deficiency anaemia: low impact on outcome in the medium term despite high diagnostic yield.

INTRODUCTION: Small bowel capsule endoscopy (SBCE) is a useful diagnostic modality in small bowel disorders. Iron deficiency anaemia (IDA) is one of the most common indications for SBCE. However, there are limited data on the diagnostic yield for IDA alone, and little is known about the clinical impact and long-term outcome of patients following SBCE. AIM: To determine the diagnostic yield of SBCE in IDA and to examine outcome. MATERIALS AND METHODS: A retrospective review of a tertiary referral centre's database over a 21-month time period was carried out. Information on follow-up and management was obtained through chart review. RESULTS: In all, 309 SBCEs were identified, 30% (n=93) for anaemia and in 70% (n=65), follow-up data were available. The small bowel diagnostic yield for IDA was 53% (n=35), including angiodysplasia 49% (n=17), nonspecific inflammation 34% (n=12), active bleeding 11% (n=4) and Crohn's disease 6% (n=2). In addition, 16% (n=10) had abnormalities (gastritis, gastric antral vascular ectasia, duodenitis) outside the small bowel. In all, 42% (n=27) were persistently anaemic after a mean follow-up of 9.3 months. Of these, 52% (n=14) and 48% (n=13) had positive and negative SBCEs, respectively. In total, SBCE led to a change in treatment in 28 patients (44%), of whom 17 (61%) remained anaemic. CONCLUSION: This study shows a high overall diagnostic yield for SBCE in IDA 71% (n=45). Despite the majority, 53% (n=24), of patients with positive tests receiving specific treatment, 61% (n=17) remained anaemic in the long term. SBCE results were not predictive of long-term outcome even when stratified for a change in management.

The optimization of wireless power transmission: design and realization.

BACKGROUND: A wireless power transmission system is regarded as a practical way of solving power-shortage problems in multifunctional active capsule endoscopes. METHODS: The uniformity of magnetic flux density, frequency stability and orientation stability are used to evaluate power transmission stability, taking into consideration size and safety constraints. Magnetic field safety and temperature rise are also considered. Test benches are designed to measure the relevent parameters. Finally, a mathematical programming model in which these constraints are considered is proposed to improve transmission efficiency. To verify the feasibility of the proposed method, various systems for a wireless active capsule endoscope are designed and evaluated. RESULTS: The optimal power transmission system has the capability to supply continuously at least 500 mW of power with a transmission efficiency of 4.08%. CONCLUSIONS: The example validates the feasibility of the proposed method. Introduction of novel designs enables further improvement of this method.

In vivo microscopic imaging of the bronchial mucosa using an endo-cytoscopy system.

OBJECTIVES: We investigated the capabilities of an endo-cytoscopy system (ECS) that enables microscopic imaging of the tracheobronchial tree during bronchoscopy, including normal bronchial epithelium, dysplastic mucosa and squamous cell carcinoma. METHODS: The newly developed ECS has a 3.2 mm diameter that can be passed through the 4.2 mm working channel of a mother endoscope for insertion of the ECS. It has a high magnification of 570× on a 17 in. video monitor. Twenty-two patients (7 squamous cell carcinoma, 11 squamous dysplasia and 4 after PDT therapies) were underwent white light, NBI light and AFI bronchoscopy. Both abnormal areas of interest and normal bronchial mucosa were stained with 0.5% methylene blue and examined with ECS at high magnification (570×). Histological examinations using haematoxylin and eosin staining were made of biopsied specimens. Analyzed ECS images were compared with the corresponding histological examinations. RESULTS: In normal bronchial mucosa, ciliated columnar epithelial cells were visible. In bronchial squamous dysplasia, superficial cells with abundant cytoplasm were arranged regularly. In squamous cell carcinoma, large, polymorphic tumor cells showed increased cellular densities with irregular stratified patterns. These ECS images corresponded well with the light-microscopic examination of conventional histology. CONCLUSION: ECS was useful for the discrimination between normal bronchial epithelial cells and dysplastic cells or malignant cells during bronchoscopy in real time. This novel technology has an excellent potential to provide in vivo diagnosis during bronchoscopic examinations.

Safety, reliability and limitations of the given patency capsule in patients at risk of capsule retention: a 3-year technical review.

INTRODUCTION: The patency capsule may prevent capsule retention in high-risk patients. However data on its use in routine clinical practice is limited. METHODS: Patients referred to our institution between Feb-04 and Jan-07 were reviewed. The following data was collected: presenting symptoms; medical/surgical history; medication; radiology; patency/video capsule result; subsequent investigations; clinical outcomes. RESULTS: 373 patients were referred. In 315 (84%) 'low-risk' patients (no patency capsule): delayed transit occurred in three, with no cases of capsule retention. In 58 (16%) 'high risk' patients (patency capsule): asymptomatic retention occurred in eight, all with pathology despite normal prior barium studies in six; in four cases patency location was incorrectly assessed radiologically, leading to video capsule retention and surgery in one. DISCUSSION: Most patients can safely undergo capsule endoscopy without a patency capsule. The patency capsule appears safe and is indicative of pathology when retained. Assessment of patency capsule location post ingestion can be difficult, and if barium radiology is equivocal a limited abdominal computed tomography (CT) scan is suggested.