Ricardo Sarriá

Effect of double-balloon enteroscopy on pancreas: An experimental porcine model

AIM To evaluate the effect of double-balloon enteroscopy (DBE) on pancreas histology and levels of pancreatic enzymes. METHODS Conventional upper gastrointestinal endoscopy was performed on five control pigs. Oral DBE was performed with an EN-450T5 enteroscope on 20 pigs. Two experimental groups (10 pigs each) were defined according to DBE duration: 90 min for Group 1 and 140 min for group 2. During oral insertion, the balloons were not inflated in the descending part of the duodenum to avoid the minor duodenal papilla. Serum amylase, lipase and C-reactive protein (CRP) levels were monitored before the procedure and repeated every 30 min until the exploration was finished, as well as 24 h and 7 d after. After the procedure and for a total of 7 d, the pigs were observed twice a day for signs of decreased activity, irritability, vomiting or anorexia. Gross and microscopic examination of the pancreas was performed on day 7. RESULTS All animals tolerated DBE without clinical manifestations of acute pancreatitis. Experimental groups had higher levels of enzymes than the control group at 24 h. Throughout the exploration, the amylase levels increased significantly above the baseline 24 h after DBE, although the increase was not statistically significant and did not reach 20% of the baseline. An increase in lipase and CRP was observed at 24 h after the procedure, although by day 7, all enzymatic levels had returned to baseline. No differences between groups 1 and 2 were found for any enzyme and sampling site during and after the procedure. Similarly, no correlation between insertion depth and enzyme levels was observed. Direct in situ and post-removal inspection of the pancreas did not show any evidence of fluid collection, abscesses or hemorrhage. Histological examination of the pancreas from groups 1 and 2 revealed the existence of focal areas (0.14-0.26 mm2) of ischemic necrosis in 47.4% of the animals. In the pigs with damaged pancreas, the left lobe (tail) was always affected. However, this only happened in 83.3% of the samples from the right lobe (head) and in 33.3% of the samples from the body of the pancreas. Significant differences were found between the left lobe (tail) and the body for the percentage of affected pancreas. Both the size of the lesions and the percentage of affected pancreas were higher in the left pancreatic lobe (tail). The presence of the lesions was not related to the exploration length. CONCLUSION The increase in pancreatic enzymes after DBE could be related to focal points of pancreatic ischemic necrosis due to mechanical stress.

Plastinated heart slices aid echocardiographic interpretation in the dog.

Our aim was to compare plastinated sections of the canine heart with corresponding two-dimensional (2D) echocardiographic images. Thirteen dog hearts were fixed by dilation and then processed by the S10 silicon plastination method (Biodur). Two dogs without evidence of cardiac disease were imaged using 2D echocardiography so as to obtain a complete series of the standard right and left parasternal images, which were compared with corresponding plastinated slices obtained by knife sectioning of the hearts. The plastinated slices revealed the internal anatomy of the heart with great detail and were particularly useful to display the spatial relationship between complex anatomic structures. The plastinated slices corresponded accurately with the echocardiographic images. Because of the dilation of the right heart during the fixation process, it was not possible to obtain plastinated specimens in ventricular systole. This paper may be a reference atlas for assisting 2D echocardiography interpretation.

Morphometric study of the layers of the canine small intestine at five sampling sites.

The histology of the canine intestine has not been accurately defined. To establish the precise thickness of its different layers, whole wall samples of the small intestine were removed from 41 cadavers at five standardised sampling sites (duodenum, proximal jejunum, distal jejunum, proximal ileum and distal ileum). The total thickness was estimated by morphometry, as was the thickness of the mucosa, muscularis mucosae, submucosa and muscularis externa. In addition, the size of the lymphoid aggregates in the submucosa and the thickness of the circular and longitudinal layers within both the muscularis mucosae and the muscularis externa were estimated. The total intestinal thickness depended very much upon the thickness of the mucosa and submucosa. The mucosa decreased progressively from proximal to distal parts of the small intestine (47% reduction). The thickness of the submucosa, however, changed little from the duodenum to the distal jejunum, but increased significantly in the ileum; this change was positively correlated with the amount of lymphoid tissue. Sex influenced the thickness of the intestinal wall, with males displaying higher thickness values along the small intestine. Conversely, no correlation between bodyweight and intestinal thickness was found for any of the five sampling sites. This study gives absolute and relative values for the thickness of the layers of the dog intestine which might help in the diagnosis of small intestinal pathology from postmortem samples and/or endoscopic biopsies.

Morphometry of the canine intestine with reference to the use of double balloon endoscopy.

Double balloon endoscopy (DBE) enables the diagnosis and treatment of small intestinal disease. The dog is a potential animal model for DBE training and also a candidate for the clinical application of this technique. However, the anatomy of the canine small intestine may limit the use of DBE by restricting the push-and-pull manoeuvres required for DBE. To establish what these limitations are, the length and width of different portions of the small intestine as well as the mesenteric dependences were measured in 55 dogs. Several external parameters related to body size plus the age, weight, sex and breed were recorded. Potential restriction of the progress of the enteroscope due to narrow intestinal diameter is expected in the jejunum of mid- and small size dogs.

Carbon dioxide insufflation safety in double-balloon enteroscopy: an experimental animal study.

The aim of the present study was to assess the safety and efficacy of CO2 during double‐balloon enteroscopy (DBE) in an experimental animal model study. In this study, insufflation with room air and with CO2 was compared.

Experimental laparoscopic evaluation of double balloon versus spiral enteroscopy in an animal model.

Four pigs were subjected to enteroscopic exploration and divided into two groups: Double Balloon Enteroscopy (DBE group) and Spiral Enteroscopy (SE group). The explored length from the pylorus, the feed rate and the time of withdrawal were measured. Simultaneous laparoscopic view allowed evaluation of the enteroscopy maneuvers. During laparoscopy control it was easy to see air trapped in the intestine bent over the overtube, mainly in the DBE group, whereas vascular stress of the bowel wall was higher in the SE group, which was probably related with the spiral torsion observed in the jejunal vessels and the root of the mesentery (Fig. 1). This was not observed in the DBE group. Nevertheless, subperitoneal ecchymosis was observed in both groups, but with higher significance in the SE group. Furthermore, a small tear in the visceral peritoneum appeared in one pig (Fig. 2). The small bowel examined was 219.6 12.7 and 180.0 14.1 cm long, the feed rate was 4.05 and 5.62 cm/min and the time of withdrawal was 67 and 138 s, for the DBE and SE groups, respectively. The vascular supply to the bowel was apparently more altered in the SE group, which is likely determined by a compressive effect of the DSB overtube on the intestinal wall and intense rotation of the root of the mesentery. Akerman et al. indicate that small-bowel pleating is accomplished without apparent twisting of the small bowel because the mesentery attachment to the small bowel resists its rotation; however the laparoscopic visualization in the porcine model suggested that this process could be more iatrogenic than expected. The clockwise rotation of the DSB overtube mimics the motion of a corkscrew and pleats the small bowel onto the overtube, hence twisting the bowel and the mesenteric vessels in a more compressive way. The longer time of withdrawal in the SE could represent a clinical problem.

Anatomy of the temporomandibular joint in the cat: a study by microdissection, cryosection and vascular injection.

The minute anatomy of the temporomandibular joint (TMJ) is of great clinical relevance in cats owing to a high number of lesions involving this articulation. However, the precise anatomy is poorly documented in textbooks and scientific articles. The aim of this study was to describe, in detail, the TMJ anatomy and its relationship with other adjacent anatomical structures in the cat. Different anatomical preparations, including vascular and articular injection, microdissection, cryosection and plastination, were performed in 12 cadaveric cats. All TMJ anatomical structures were identified and described in detail. A thorough understanding of the TMJ anatomy is essential to understand the clinical signs associated with TMJ disorders, to locate lesions precisely and to accurately interpret the results in all diagnostic imaging techniques.

Ultrasonographic and Anatomic Study of the Canine Elbow Joint

OBJECTIVE To (1) assess the canine elbow joint using a high frequency transducer (18 MHz); (2) describe the echogenicity and echo texture of the joint; and (3) correlate the ultrasonographic images with transparent plastinated anatomic sections. DESIGN Descriptive study. SAMPLE POPULATION German Shepherd cross-breed dogs (cadavers, n = 10; live dogs, n = 5). METHODS Elbow joints of 10 adult German Shepherd cross-breed dog cadavers were examined by ultrasonography and then 5 cadavers were selected for use in an anatomic study, in which 2 mm thick sections were obtained in the same planes as in the ultrasonographic protocol. Sections were plastinated using the E-12 plastination method and correlated to the corresponding ultrasonographic images. The elbow joints of 5 German Shepherd adult dogs were assessed by ultrasonography for comparison with cadaver images. RESULTS Good correspondence of soft tissue and bone structures was obtained between ultrasound images and anatomic sections. There was no difference in the ultrasonographic appearance of elbows of cadavers and live dogs in which the muscular, ligamentous, and bone components of the joints were evaluated. CONCLUSION This study presents a descriptive comparison of anatomic and ultrasonographic images, which will offer clinicians a more comprehensive understanding of the anatomic structures of the canine elbow joint and serve as reference for further imaging diagnostic studies because of the precise correspondence between anatomic plastinated sections and ultrasonographic images.