Magnet and wire remodeling for the treatment of candy cane syndrome: first case series of a new approach (with video).

BACKGROUND AND AIMS: Candy cane syndrome (CCS) is an adverse event (AE) from gastrectomy or gastric bypass and end-to-side anastomosis to a jejunal loop. Preferential passage of food to the blind loop induces early satiety, pain, and regurgitation. An endoscopic device that combines 2 magnets and a self-retractable wire was designed to perform progressive septotomy with marsupialization. We evaluated the clinical safety and efficacy of this treatment in CCS. METHODS: Consecutive patients presenting with symptoms associated with CCS after gastrectomy or Roux-en-Y gastric bypass were treated with the MAGUS (Magnetic Gastrointestinal Universal Septotome) system. Weight, dysphagia, pain scores, 12-item Short Form Survey quality of life physical and mental scores, GERD Health-Related Quality of Life, and Eckardt score were measured at baseline and 1 and 3 months postprocedure. Satisfaction with therapy and AEs were monitored during follow-up. RESULTS: Fourteen consecutive patients with CCS were enrolled in the study. Thirteen MAGUS systems migrated within 28 days after achieving uneventful complete septotomy. In 1 patient the magnet had to be collected from the right-sided colon after 1 month. Treatment was completed in a single endoscopy session. Dysphagia score (2 [1-3] vs 1 [1-1], P = .02), pain score (7 [6-8] vs 1 [0-1], P = .002), Eckardt score (5 [3-8] vs 1 [0-2], P = .002), GERD Health-Related Quality of Life score (37 [29-45] vs 8 [6-23], P = .002), and quality of life physical and mental scores were all significantly improved at 3 months. No device or procedure-related serious AEs were observed. One patient died during follow-up from evolution of oncologic disease. CONCLUSIONS: Endoluminal septotomy using a retractable wire and magnet system in CCS is feasible and safe, with rapid improvement of symptoms. (Clinical trial registration number: NCT04480216.).

Magnets and a self-retractable wire for endoscopic septotomies: from concept to first-in-human use.

BACKGROUND: A medical device that allows simple and safe performance of an endoscopic septotomy could have several applications in the gastrointestinal (GI) tract. We have developed such a device by combining two magnets and a self-retractable wire to perform a progressive septotomy by compression of the tissues. We describe here the concept, preclinical studies, and first clinical use of the device for the treatment of symptomatic epiphrenic esophageal diverticulum (EED). METHODS: The MAGUS (MAgnetic Gastrointestinal Universal Septotome) device was designed based on previous knowledge of compression anastomosis and currently unmet needs. After initial design, the feasibility of the technique was tested on artificial septa in pigs. A clinical trial was then initiated to assess the feasibility and safety of the technique. RESULTS: Animal studies showed that the MAGUS can perform a complete septotomy at various levels of the GI tract. In two patients with a symptomatic EED, uneventful complete septotomy was observed within 28 and 39 days after the endoscopic procedure. CONCLUSIONS: This new system provides a way of performing endoluminal septotomy in a single procedure. It appears to be effective and safe for managing symptomatic EED. Further clinical applications where this type of remodeling of the GI tract could be beneficial are under investigation.

Optimization and assessment of a novel gastric electrode anchoring system designed to be implanted by minimally invasive surgery.

A novel electrode anchoring design and its implantation procedure, aiming for a minimally invasive solution for gastric electrical stimulation, are presented. The system comprises an anchor made of a flexible body embedding two needle-shaped electrodes. The electrodes can easily switch from a parallel position - to pierce the stomach - to a diverging position - enabling them to remain firmly anchored into the muscular layer of the stomach. Key device parameters governing anchoring stability were assessed on a traction test bench, and optimal values were derived. The device was then implanted in six dogs by open surgery to assess its anchoring durability in vivo. Computed tomography images showed that the electrodes remained well placed within the dogs' gastric wall over the entire assessment period (more than one year). Finally, a prototype of a surgical tool for the minimally invasive device placement was manufactured, and the anchoring procedure was tested on a dog cadaver, providing the proof of concept of the minimally invasive implantation procedure. The use of our electrode anchoring system in long-term gastric electrical stimulation is promising in terms of implantation stability (the anchor withstands a force up to 0.81 N), durability (the anchor remains onto the stomach over one year) and minimal invasiveness of the procedure (the diameter of the percutaneous access is smaller than 12 mm). Moreover, the proposed design could have clinical applications in other hollow organs, such as the urinary bladder.

In Vivo Validation of a Less Invasive Gastrostimulator.

Gastrointestinal stimulator implants have recently shown promising results in helping obese patients lose weight. However, to place the implant, the patient currently needs to undergo an invasive surgical procedure. We report a less invasive procedure to stimulate the stomach with a gastrostimulator. After attempting fully endoscopic implantation, we more recently focused on a single incision percutaneous procedure. In both cases, the challenges in electronic design of the implant are largely similar. This article covers the work achieved to meet these and details the in vivo validation of a gastrostimulator aimed to be endoscopically placed and anchored to the stomach.

Power Strategy in DC/DC Converters to Increase Efficiency of Electrical Stimulators.

Power efficiency is critical for electrical stimulators. Battery life of wearable stimulators and wireless power transmission in implanted systems are common limiting factors. Boost DC/DC converters are typically needed to increase the supply voltage of the output stage. Traditionally, boost DC/DC converters are used with fast control to regulate the supply voltage of the output. However, since stimulators are acting as current sources, such voltage regulation is not needed. Banking on this, this paper presents a DC/DC conversion strategy aiming to increase power efficiency. It compares, in terms of efficiency, the traditional use of boost converters to two alternatives that could be implemented in future hardware designs.

Design and Implementation of a Less Invasive Gastrostimulator.

Gastrointestinal stimulator implants have recently shown positive results in helping obese patients lose weight. However, to place the implant, the patient currently needs to undergo an invasive surgical procedure. Our team is aiming for a less invasive procedure to stimulate the stomach with a gastrostimulator. Attempts covered fully endoscopic implantation and, more recently, we have focussed on a single incision laparoscopic procedure. Whatever the chosen implantation solution, the electronic design of the implant system shares many challenges. This paper covers the work achieved to meet these.