US Patent 9028394 Self-adjusting mechanical gastric band

A self-adjusting gastric band applies a substantially constant force to a patient's fundus in order to facilitate weight control. The self-adjusting gastric band is capable of automatically relaxing and contracting in response to changes in the patient's fundus or in response to a large bolus passing through the patient's fundus that is constricted by the gastric band. The self-adjusting gastric band is automatically adjustable without hydraulic fluid and without external physician intervention. The self-adjusting gastric band comprises a movable member and a biasing mechanism coupled to the movable member to facilitate applying the substantially constant force against the fundus as the fundus changes size, shape and/or position.