Browsing by Author "Moreira, I"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- In vivo assessment of gastrotomy closure with over-the-scope clips in an experimental model for varicocelectomyPublication . Rolanda, C; Lima, E; Silva, D; Moreira, I; Pêgo, JM; Macedo, G; Correia-Pinto, JBACKGROUND: Gastrotomy closure remains the major limiting factor for human translation of transgastric surgery; the over-the-scope clip (OTSC) system was proposed as a possibility for this purpose. Transgastric access is good for a pelvic approach, making varicocelectomy a possible indication for natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE: To evaluate the reliability of the OTSC system in vivo after transgastric testicular vessel ligation (varicocelectomy model). DESIGN: There were 3 experimental groups (5 animals in each): groups 1 and 3, gastrotomy dilation up to 18 mm, surgery was performed with a double-channel endoscope; group 2, gastrotomy dilation up to 13 mm, surgery was performed with a single-channel endoscope. SETTING: Surgical Sciences Research Domain, Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. INTERVENTIONS: Bilateral testicular vessel ligation by transgastric access. Gastrotomy closed with the largest version of OTSC system (12 mm): a single clip in groups 1 and 2, and 2 clips in group 3. Animals were monitored for 2 weeks, killed, and submitted for necropsy. MAIN OUTCOME MEASUREMENTS: Adequacy of closure and healing after the use of the OTSC system. Statistical analysis. RESULTS: Vessel ligation was easily achieved in all groups. Although differences in the complication rate did not reach statistical significance (P = .099), there was a clear tendency for a better prognosis in groups 2 and 3 than group 1. In fact, only 2 animals from group 1 had complications related to incomplete gastrotomy closure. LIMITATIONS: Small number of animals per group; nonrandomized study. CONCLUSIONS: The OTSC system was shown to be easy and efficient for gastrotomy closure in a survival experimental model of varicocelectomy, when correctly matching the gastrotomy size with the clip size and/or number.
- Peroral esophageal segmentectomy and anastomosis with single transthoracic trocar: a step forward in thoracic NOTESPublication . Rolanda, C; Silva, D; Branco, C; Moreira, I; Macedo, G; Correia-Pinto, JBACKGROUND AND STUDY AIMS: A transesophageal natural orifice transluminal endoscopic surgery (NOTES) approach has been proposed for thoracic and mediastinal access. Similarly to transgastric surgery, serious limitations remain related to creating an esophagotomy and its safe closure. A hybrid approach in thoracic NOTES could work as an intermediate step before pure transesophageal NOTES. We assessed the benefit of hybrid thoracic NOTES for peroral segmental esophagectomy and subsequent complete esophageal anastomosis with a single transthoracic port. METHODS: Two protocols were used to attempt esophago-esophageal anastomosis: ex vivo using a phantom model (n = 5), and in vivo after esophageal mobilization, and segmental esophagectomy achieved using either a gastroscope (flexible) (n = 5) or thoracoscope (rigid) instruments (n = 5). A forward-viewing double-channel endoscope and a transthoracic operative thoracoscope with a working channel were coordinated in order to create a complete single-layer, end-to-end esophageal anastomosis ex vivo as well as in vivo. Feasibility and anastomosis quality were evaluated by inside and outside assessment of: patency, the incorporation of mucosa in all stitches, and a leak test. RESULTS: Anastomosis was achieved in all ex vivo experiments and thoracoscopically-led in vivo procedures. All anastomoses were patent, allowing distal passage of the endoscope, with mucosa incorporation. In in vivo experiments, a leak was detected in three animals and corrected with additional stitching. CONCLUSIONS: Peroral esophageal anastomosis with a single transthoracic trocar is feasible, which may represent a step forward in thoracic NOTES.
- Third-generation cholecystectomy by natural orifices: transgastric and transvesical combined approachPublication . Rolanda, C; Lima, E; Pêgo, JM; Henriques-Coelho, T; Silva, D; Moreira, I; Macedo, G; Carvalho, JL; Correia-Pinto, JBACKGROUND: An isolated transgastric port has some limitations in performing transluminal endoscopic cholecystectomy. However, transvesical access to the peritoneal cavity has recently been reported to be feasible and safe. OBJECTIVE: To assess the feasibility and the technical benefits of transgastric and transvesical combined approach to overcome the limitations of isolated transgastric ports. DESIGN: We created a transgastric and transvesical combined approach to perform cholecystectomy in 7 consecutive anesthetized female pigs. The transgastric access was achieved after perforation and dilation of the gastric wall with a needle knife and with a balloon, respectively. Under cystoscopic control, an ureteral catheter, a guidewire, and a dilator of the ureteral sheath were used to place a transvesical 5-mm overtube into the peritoneal cavity. By using a gastroscope positioned transgastrically and a ureteroscope positioned transvesically, we carried out cholecystectomy in all animals. RESULTS: Establishment of transvesical and transgastric accesses took place without complications. Under a carbon dioxide pneumoperitoneum controlled by the transvesical port, gallbladder identification, cystic duct, and artery exposure were easily achieved in all cases. Transvesical gallbladder grasping and manipulation proved to be particularly valuable to enhance gastroscope-guided dissection. With the exclusion of 2 cases where mild liver-surface hemorrhage and bile leak secondary to the sliding of cystic clips occurred, all remaining cholecystectomies were carried out without incidents. LIMITATIONS: Once closure of the gastric hole proved to be unreliable when using endoclips, the animals were euthanized; necropsy was performed immediately after the surgical procedure. CONCLUSIONS: A transgastric and transvesical combined approach is feasible, and it was particularly useful to perform a cholecystectomy through exclusive natural orifices.
- Third-generation nephrectomy by natural orifice transluminal endoscopic surgeryPublication . Lima, E; Rolanda, C; Pêgo, JM; Henriques-Coelho, T; Silva, D; Osório, L; Moreira, I; Carvalho, JL; Correia-Pinto, JPURPOSE: Recently there has been increasing enthusiasm for performing simple abdominal procedures by transgastric surgery. We previously reported the usefulness of a combined transgastric and transvesical approach to cholecystectomy. In this study we assessed the feasibility of combined transgastric and transvesical approach for performing a more complex surgical procedure, such as nephrectomy, in a porcine model. MATERIALS AND METHODS: In a nonsurvival study combined transgastric and transvesical approaches were established in 6 female pigs. Under ureteroscope guidance we installed a transvesical 5 mm over tube into the peritoneal cavity and a flexible gastroscope was passed orally into the peritoneal cavity by a gastrotomy. We performed right or left nephrectomy with instruments introduced by the 2 devices that worked in the renal hilum, alternating device intervention for dissection and retraction procedures. RESULTS: Four right and 2 left nephrectomies were performed. There were no complications during the creation of transvesical and transgastric access. In all animals we visualized the 2 kidneys. The renal vessels and ureter were reasonably individualized and ligated separately with ultrasonic scissors, which were introduced through the transvesical port. In 2 early cases mild hemorrhage occurred after ultrasonic ligation. To overcome this complication we applied clips successfully before ultrasonic ligation in the remaining animals. Thus, complete renal release and mobilization to the stomach were achieved in all animals. CONCLUSIONS: Nephrectomy by natural orifices using the combined transgastric and transvesical approach is technically feasible, although to our knowledge there is no reliable method for removing the specimen with current instruments.