Abstract: Method for treating obesity in a mammal which has an oesophagus connected to a stomach at the level of an oesophagogastric junction region, the oesophagogastric junction region exhibiting a zigzag oesophagogastric mucosal junction line and a transverse mucosal fold raised by sling fibres, the mucosal fold being located downstream of the Z line, the mucosal fold and the Z line defining a conical structure delimiting an opening to the stomach, including creating a first stricture zone by reducing the cross section of the opening by introducing at least a first biocompatible substance implanted on or in the wall of the conical structure, at least at the level of the mucosal fold.

Abstract: Constriction device (1) which can be at least partially implanted in the human or animal body, comprising a constriction member (2) forming a ring in its operational configuration, said constriction member including a flexible band (12), of which the two ends (12a, 12b) are adjacent to one another in the operational configuration, and a means (3) for actuating the constriction member, characterized in that, in cooperation, on the one hand, at least one end (12b) of the flexible band (12) includes a tractile element (13) for moving said end relative to the other end (12a), generating a radial deformation of the constriction member, and, on the other hand, the actuating means (3) comprises a member (25) for pulling the tractile element (13).