Magnamosis III: delivery of a magnetic compression anastomosis device using minimally invasive endoscopic techniques.

PURPOSE: Magnamosis creates a secure sutureless anastomosis through magnetic compression. In this study, we further develop and test delivery devices capable of creating a secure duodeno-colonic anastomosis using available minimally invasive endoscopic techniques. METHODS: Eight pigs underwent general anesthesia. Colonoscopy was used to deliver 1 magnetic ring to the hepatic flexure. Simultaneously, upper endoscopy delivered the other magnetic ring into the duodenum using a variety of techniques. The 2 magnetic rings were brought into magnetic proximity under laparoscopic guidance. The pigs were recovered and examined daily followed by sacrificing at 1, 2, 4, and 6 weeks. RESULTS: The device designed to deliver and release each magnetic ring evolved from using a guide wire and balloon devices to redesigning the magnetic ring casing with a groove to accommodate an endoscopic snare. Laparoscopic visualization assured safe magnet mating of intestinal segments. The duodeno-colonic anastomoses created with the snare yielded widely patent anastomoses. In vitro testing revealed excellent burst pressure. Histology revealed complete healing as early as 1 week. CONCLUSION: We redesigned the magnamosis device to facilitate delivery by endoscopic techniques. The snare technique allows endoscopic positioning and controlled release of the magnetic rings for a secure side-to-side duodeno-colonic anastomosis.

Hyoid bone advancement for improving airway patency: cadaver study of a magnet-based system.

OBJECTIVE: The goal of this study was to evaluate the effect of anterior forces applied to the hyoid bone on upper airway dimensions and airflow. The study also evaluated the feasibility of applying these forces using a novel magnet-based system. STUDY DESIGN: Human cadaver specimens. SETTING: Surgical laboratory. SUBJECTS AND METHODS: Five fresh cadaveric specimens were evaluated using fluoroscopy and computed tomography to examine upper airway opening as well as an airflow model to examine upper airway collapse. Anteriorly directed force was applied to the hyoid bone directly using a wire and with a magnet-based system called the Magnap device. Direct application of force was examined with an axial load frame or suspended weights. The magnet-based system applied similar forces using an internal, implanted magnet secured to the hyoid bone and an external magnet housed within an orthotic brace. RESULTS: A force of 2 N perpendicular to the neck skin advanced the hyoid 1 cm, opened the upper airway, and significantly improved airflow. The implanted magnet-based device generated similar forces, with similar effects on the upper airway. CONCLUSION: Application of anterior force to the hyoid bone improved upper airway dimensions and airflow in the human cadaver model. These results justify additional study to evaluate the benefits of this magnet-based system as a possible treatment of upper airway obstruction.