fig1

Figure 1. (A) Schematic illustration of the bench model used to study the new antireflux device based on magnets. On the right, there is a flaccid polyethylene tube 2.8 cm in diameter, mimicking the gastroesophageal junction. It is squeezed perpendicularly by two rectangular magnets made of plastoferrite (Flexo) 2 cm × 4 cm × 0.5 cm with an attraction force of 0.36 N/cm² when put in contact and 0.16 N/cm² at 7 mm distance. It creates a high-pressure zone 2 cm wide that divides the tube into Segments E (esophagus ) and G (stomach). The tube is perfused with water by a pump, and the pressure variations of each segment are detected with two pressure transducers and recorded by a polygraph. (B) Intraluminal pressure variations in Segments G (bottom) and E (top). The pressure of Segment G (stomach) was progressively increased by the pump, and, when it reached the value of about 11.5 mmHg, the magnets, simulating the sphincter, were detached, so that the pressure in Segment E (esophagus) started to increase, mimicking gastroesophageal reflux and reaching the level of Segment G. Once the pump stopped, the pressure dropped and the magnets adhered again, closing the passage. Exchanging the Segment E for G and Segment G for E, this sequence of events may represent the passage of a bolus through the zone squeezed by the magnets. From: Ref.^[7] (Reprinted with permission).