Patent ID: 9730698
Date: 2017-08-15
CPC Classifications: A61B

Claim:
1. A ring for treating Small For Size syndrome suitable for hepatectomies and liver transplants, the ring having an adjustable inner diameter and being intended to be implanted and closed around the portal vein, upstream of the liver, in order to control the diameter of the portal vein and thus the flow rate and/or pressure of a fluid circulating in the portal vein, the ring comprising: an outer belt comprising two outer lips extending in the centrifugal direction and capable of being joined to one another in a diametral plane, in a reversible manner, in order to put the ring in a closed position around the portal vein, the outer belt having a constant diameter in the closed position; an inner chamber that can be inflated and deflated in the closed position, so as to vary an inner diameter of said inner chamber; a flexible inflation/deflation tube, a proximal end of which is connected to the inner chamber and a distal end of which is intended to be connected to inflation means; inflation means connected to the distal end of the flexible tube; and at least one suture to join the outer lips to one another to close the ring, the suture being selected to break in the event of overpressure in the ring, the outer belt and the inner chamber forming open collars, at least one of which is equipped with means for closing the ring around the portal vein; wherein the inner chamber, at rest and in the closed position, has an inner diameter corresponding to a smallest reduced diameter required when in use for controlling the diameter of the portal vein, the inner diameter of the inner chamber being configured to reduce by at the most 55% the diameter of the portal vein D vp to a minimal value D vpr , the inflation means being controlled to allow the modulation of the diameter of the portal vein D vp between the minimal value D vpr and a normal diameter D vpn in which the ring does not reduce the diameter of the portal vein D vp , said modulation consisting in deflating the ring in order to increase the inner diameter, so as to reduce the portal pressure downstream of the ring and maintain the intrahepatic pressure at a value less than or equal to 20 mm Hg.