Videoendoscopy: an effective and efficient way to perform multiple visceral biopsies in small animals.

Because major surgery is usually required to obtain biopsies of abdominal organs, regulations tend to limit the number of procedures on individual animals to one. This study was conducted to develop a more humane, minor, comparatively cost-effective, minimally invasive surgical procedure, which reduces surgical trauma and the number of animals used. Biopsy techniques were developed in two nonsurvival rabbit surgeries. Safety and efficacy of multiple procedures were assessed in survival studies on four rabbits. Anesthesia was induced with ketamine/xylazine and maintained with isoflurane. Initial carbon dioxide insufflation (6 mmHg) was achieved through a Veress needle. A triangulated 5-mm port technique allowed introduction of pediatric 3.5- to 5.0-mm laparoscopic instruments. Biopsies of liver, spleen, kidney, and full-thickness bowel were obtained and evaluated for suitability (size) for polymerase chain reaction, in-situ hybridization, and histopathology studies. Animals in survival studies were assessed for infection, pain, bleeding, adhesion development, bowel function, and intestinal stenosis. All had normal appetite and stools within 48 h postoperatively. Biopsies obtained from either a Tru-Cut Biopsy Needle, 3.5- to 5.0-mm biopsy cups, or with the aid ofa pre-tied loop were adequate for all studies. There was no postoperative bowel obstruction, wound infection, or bleeding. Mean hematocrit decrease at 24 h postoperative was 3.4% +/- 6.7%. Adhesions formed at 9/52 (17%) evaluable sites. Multiple visceral organ biopsy under videoendoscopic guidance constitutes a minor procedure and is a promising means for longitudinal studies in animals. Utility for ill animals remains to be determined.

Does botulinum toxin injection make esophagomyotomy a more difficult operation?

BACKGROUND: Some patients with achalasia treated by botulinum toxin injection still require an esophagomyotomy. In this study, we analyzed the impact of botulinum toxin injection on the technical aspects and outcome of esophagomyotomy. METHODS: We studied 57 patients, with a mean age of 46 years (range, 12-97) who were treated between January 1995 and March 1998 by esophagomyotomy performed via minimally invasive techniques by one team. Operative reports, videotapes, and clinical outcome were analyzed to define the technical difficulties, perforations, and outcome. RESULTS: Fifteen of the 57 patients had received one or more injections of botulinum toxin (botox group) preoperatively. Difficulties in dissection of the submucosal plane were encountered in eight of the 15 cases (53.3%), and a mucosal laceration (perforation) occurred in two cases (13.3%). Forty-two of the 57 patients had not received any injections (non-botox group). In three patients (7%), difficulties in identifying or following the submucosal plane were encountered, although 29 patients had one or more previous dilations, and perforation occurred in one case (2.4%). All mucosal injuries were repaired laparoscopically, and the patients recovered without obvious sequelae. Dysphagia improved significantly after the operation in both groups (botox group, from preoperative score of 3. 8 to a postoperative score of 0.7; non-botox, from a score of 3.4 preoperatively to 0.5 postoperatively). Regurgitation also improved in both groups (botox, 2.7 preoperatively, 0.92 postoperatively; non-botox group, 2.0 preoperatively, 0.56 postoperatively). CONCLUSIONS: Injection of botulinum toxin significantly increases the technical difficulties and thus the potential risk of esophagomyotomy. The immediate results were equally good for both groups in our series, but the long-term sequelae of repeated injections are unknown. Laparoscopic Heller myotomy is a safe and effective procedure even after unsuccessful treatment with botulinum toxin.