A new alternative for a transjugular intrahepatic portosystemic shunt: EUS-guided creation of an intrahepatic portosystemic shunt (with video)

Background: Transjugular intrahepatic portosystemic shunt (TIPSS) is an effective treatment for portal hypertension and its associated complications. EUS-guided creation of an intrahepatic portosystemic shunt (IPSS) may become a useful alternative to conventional TIPSS. Objective: To assess the feasibility of EUS-guided IPSS creation in a live porcine model. Setting: Acute and survival experiments in 50-kg pigs. Design and interventions: Under linear-array EUS guidance, the hepatic vein (HV) and then the portal vein (PV) were punctured with a 19-gauge FNA needle. A 0.035-inch guidewire was advanced through the needle into the PV lumen. The needle was exchanged over the wire, a metal stent was deployed under EUS and fluoroscopic guidance, and the distal end of the stent was positioned inside the PV and the proximal end within the HV. Eight animals were euthanized after the procedure, and 2 animals were kept alive for 2 weeks. Main outcome measurements: Successful EUS-guided IPSS creation. Results: Portosystemic shunt placement was successful in all animals. Intrahepatic vascular puncture and stent deployment were technically easy. Portosystemic flow through the shunt was documented by portal venogram and EUS Doppler. Necropsy performed after acute and survival experiments revealed no evidence of bleeding or damage to any intraperitoneal organs. There were no complications during the follow-up period in the 2 animals that were kept alive. Limitation: Experiments were performed in healthy animals with normal PV pressure. Conclusion: EUS-guided IPSS creation is technically feasible and may become an alternative to the currently used method of TIPSS placement

Gastric Wall Healing After NOTES Procedures: Closure With Endoscopic Clips Provides Superior Histological Outcome Compared With Threaded Tags Closure

Background: Closure of the transgastric access to the peritoneal cavity is a critical step in natural orifice transluminal endoscopic surgery (NOTES). Objective: To perform a direct comparison of the histological healing post clips and threaded tags (T-tags) closure after transgastric NOTES procedures. Design and intervention: Twelve survival porcine experiments. After standardized endoscopic gastric wall puncture, balloon-dilation, and transgastric peritoneoscopy, closure of the gastric wall was performed with either clips or T-tags. Necropsy at 14 days was performed for histological evaluation of 2-mm interval transversal cross sections of the gastrotomy site. Main outcome measurements: Histological healing of the gastric wall opening. Results: Endoscopic closure of the gastrotomy was successfully achieved in all 12 animals, followed by an uneventful 2-week clinical follow-up. Transmural healing was seen in 3 (75%) animals after clip closure compared with only 1 (12.5%) in the group with T-tag closure (P = .06). Gastric wall muscular bridging was observed in 4 (100%) animals with clip closure compared with only 1 (12.5%) in the group with T-tag closure (P = .01). Limitations: Animal model with short-term follow-up. Conclusions: Endoscopic clip closure results in a layer-to-layer transmural healing of the gastric wall. In contrast, T-tag gastric wall plication impairs gastric layer bridging. These findings might guide the future design of new endoscopic devices and techniques for gastrotomy closure after NOTES procedures

A 2-microm Continuous-Wave Laser System for Safe and High-Precision Dissection During NOTES Procedures

Introduction: Lasers 2-microm in wavelength offer efficient tissue cutting with limited thermal damage in biological tissue. Objective: To evaluate the dissection capabilities of a 2-microm continuous-wave laser for NOTES procedures. Methods and procedures: We conducted 18 acute animal experiments. Group 1 (three animals): transcolonic access to the peritoneal cavity (15-W transcolonic laser puncture, balloon dilation over the laser probe). Group 2 (six animals): transcolonic access with needle-knife puncture and balloon dilation. Group 3 (three animals): transgastric access to the peritoneal cavity (similar technique as group 1) followed by laser-assisted dissection of the kidney. In one animal of group 3, a therapeutic target (hematoma) was created by percutaneous puncture of the kidney. Group 4 (six animals): transgastric access (similar to the technique of group 2). Results: Translumenal access to the peritoneal cavity was achieved in 2-3 min in group 1 (significantly shorter than with the needle-knife-assisted technique, 4-5 min, p=0.02) and in 7-10 min in group 3 (compared to 6-17 min in group 4, p=0.88). In group 3, laser dissection of the parietal peritoneum and of perinephric connective tissue allowed access to the retroperitoneum with complete removal of a blood collection in the animal with puncture trauma. Laser dissection demonstrated good maneuverability, clean and rapid cutting, and excellent hemostasis. Peritoneoscopy and necropsy showed no damage of targeted tissue and surrounding organs. Conclusions: The 2-microm continuous-wave laser system showed promising capabilities for highly precise and safe dissection during NOTES procedures