Natural orifice transluminal endoscopic wedge hepatic resection with a water-jet hybrid knife in a non-survival porcine model

AIM: To explore the feasibility of a water-jet hybrid knife to facilitate wedge hepatic resection using a natural orifice transluminal endoscopic surgery (NOTES) approach in a non-survival porcine model. METHODS: The Erbe Jet2 water-jet system allows a needleless, tissue-selective hydro-dissection with a pre-selected pressure. Using this system, wedge hepatic resection was performed through three natural routes (trans-anal, trans-vaginal and trans-umbilical) in three female pigs weighing 35 kg under general anesthesia. Entry into the peritoneal cavity was via a 15-mm incision using a hook knife. The targeted liver segment was marked by an APC probe, followed by wedge hepatic resection performed using a water-jet hybrid knife with the aid of a 4-mm transparent distance soft cap mounted onto the tip of the endoscope for holding up the desired plane. The exposed vascular and ductal structures were clipped with Endoclips. Hemostasis was applied to the bleeding cut edges of the liver parenchyma by electrocautery. After the procedure, the incision site was left open, and the animal was euthanized followed by necropsy. RESULTS: Using the Erbe Jet2 water-jet system, trans-anal and trans-vaginal wedge hepatic resection was successfully performed in two pigs without laparoscopic assistance. Trans-umbilical attempt failed due to an unstable operating platform. The incision for peritoneal entry took 1 min, and about 2 h was spent on excision of the liver tissue. The intra-operative blood loss ranged from 100 to 250 mL. Microscopically, the hydro-dissections were relatively precise and gentle, preserving most vessels. CONCLUSION: The Erbe Jet2 water-jet system can safely accomplish non-anatomic wedge hepatic resection in NOTES, which deserves further studies to shorten the dissection time.

Trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife:A pilot animal study

AIM:To investigate the feasibility and safety of Natural orifice trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife in a non-survival porcine model.METHODS:Pure natural orifice transluminal endoscopic surgery(NOTES) cholecystectomy was performed on three non-survival pigs,by transumbilical approach,using a water-jet hybrid-knife. Under general anesthesia,the following steps detailed the procedure:(1) incision of the umbilicus followed by the passage of a double-channel flexible endsocope through an overtube into the peritoneal cavity;(2) establishment of pneumoperitoneum;(3) abdominal exploration;(4)endoscopic cholecystectomy:dissection of the gallbladder performed using water jet equipment,ligation of the cystic artery and duct conducted using nylon loops;and(5) necropsy with macroscopic evaluation.RESULTS:Transumbilical endoscopic cholecystectomy was successfully completed in the first and third pig,with minor bleedings. The dissection times were 137and 42 min,respectively. The total operation times were 167 and 69 min,respectively. And the lengths of resected specimen were 6.5 and 6.1 cm,respectively.Instillation of the fluid into the gallbladder bed produced edematous,distended tissue making separation safe and easy. Reliable ligation using double nylon loops insured the safety of cutting between the loops.There were no intraoperative complications or hemodynamic instability. Uncontrolled introperative bleeding occurred in the second case,leading to the operation failure.CONCLUSION:Pure NOTES trans-umbilical cholecystectomy with a water-jet hybrid-knife appears to be feasible and safe. Further investigation of this technique with long-term follow-up in animals is needed to confirm the preliminary observation.

Transgastric endoscopic gastrojejunostomy using holing followed by interrupted suture technique in a porcine model

AIM: To demonstrate the feasibility and reproducibility of a pure natural orifice transluminal endoscopic surgery(NOTES) gastrojejunostomy using holing followed by interrupted suture technique using a single endoloop matched with a pair of clips in a non-survival porcine model.METHODS: NOTES gastrojejunostomy was performed on three female domestic pigs as follows: Gastrostomy, selection and retrieval of a free-floating loop of the small bowel into the stomach pouch, hold and exposure of the loop in the gastric cavity using a submucosal inflation technique, execution of a gastro-jejunal mucosal-seromuscular layer approximation using holing followed by interrupted suture technique with endoloop/clips, and full-thickness incision of the loop with a Dual knife.RESULTS: Pure NOTES side-to-side gastrojejunostomy was successfully performed in all three animals. No leakage was identified via methylene blue evaluation following surgery.CONCLUSION: This novel technique for preforming a gastrointestinal anastomosis exclusively by NOTES is technically feasible and reproducible in an animal model but warrants further improvement.

Percutaneous transgastric endoscopic tube ileostomy in a porcine survival model

AIM To introduce natural orifice transgastric endoscopic surgery(NOTES) tube ileostomy using pelvis-directed submucosal tunneling endoscopic gastrostomy and endoscopic tube ileostomy.METHODS Six live pigs(three each in the non-survival and survival groups) were used. A double-channeled therapeutic endoscope was introduced perorally into the stomach. A gastrostomy was made using a 2-cmtransversal mucosal incision following the creation of a 5-cm longitudinal pelvis-directed submucosal tunnel. The pneumoperitoneum was established via the endoscope. In the initial three operations of the series, a laparoscope was transumbilically inserted for guiding the tunnel direction, intraperitoneal spatial orientation and distal ileum identification. Endoscopic tube ileostomy was conducted by adopting an introducer method and using a Percutaneous Endoscopic Gastrostomy Catheter Kit equipped with the Loop Fixture. The distal tip of the 15 Fr catheter was placed toward the proximal limb of the ileum to optimize intestinal content drainage. Finally, the tunnel entrance of the gastrostomy was closed using nylon endoloops with the aid of a twin grasper. The gross and histopathological integrity of gastrostomy closure and the abdominal wall-ileum stoma tract formation were assessed 1 wk after the operation.RESULTS Transgastric endoscopic tube ileostomy was successful in all six pigs, without major bleeding. The mean operating time was 71 min(range: 60-110 min). There were no intraoperative complications or hemodynamic instability. The post-mortem, which was conducted 1-wk postoperatively, showed complete healing of the gastrostomy and adequate stoma tract formation of ileostomy.CONCLUSION Transgastric endoscopic tube ileostomy is technically feasible and reproducible in an animal model, and this technique is worthy of further improvement.

Expression of Dickkopf-related Protein 1 in Patients with Temporomandibular Osteoarthritis after Treatment with Hyaluronic Acid

We previously reported that the increased expression of Dickkopf-related protein 1(DKK1)is positively related to vascular endothelial growth factor in the synovial fluid from patients with temporomandibular joint disorders(TMDs).DKK1 is involved in angiogenic activities in the TMD synovium in vitro,but the expression of DKK1 after treatment of TMD-osteoarthritis(TMD-OA)with hyaluronic acid(HA)remains unknown.In this study,we assessed the expression of DKK1 in the synovial fluid of TMD-OA patients before and after treatment with HA via enzyme-linked immunosorbent assay.We also investigated the role of DKK1 in TMD-OA via immunohistochemical staining.The relationship between the expression of DKK1 and the clinicopathological characteristics was determined by Pearson analysis.The results showed that the expression of DKK1 was significantly decreased after treatment with HA.Correlation analyses indicated that the expression of DKK1 in the TMD-OA samples was closely correlated with mouth opening and pain.These findings suggest that DKK1 could play an important role in the pathogenesis and treatment of TMD.Reduction of the pain by HA treatment may be correlated with the decreased expression of DKK1.