A keyhole weight loss surgical technique during which a silicone balloon is inserted into the stomach, via the mouth, and inflated with water. The balloon remains in the stomach for up to 6 months before being burst and removed. This old type of bariatric surgery is no longer performed as it has been superceded by more popular obesity surgeries.
The original aim of this bariatric procedure was to reduce the functional volume of the stomach in order to treat compulsive overeating and promote weight loss. The balloon restricted the amount of solid or semi-solid food the patient could digest. This food reduction led to a reduction in calorie-intake and a consequent fall in calorie consumption. The operation did not involve any alteration in the anatomy of the stomach or digestive tract, and was completely reversible. Problems with balloon inflation were one of the drawbacks of this anti-obesity procedure.

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