When patients have very high BMI counts, such as those in excess of 55, coupled with obesity related health conditions or diseases, they are at higher risk of complications during full Gastric Bypass surgery. The aim of a Sleeve Gastrectomy is to allow for gradual decreasing of the BMI obesity level for further controlled weight loss. Sleeve Gastrectomy also allows, where appropriate, the Roux-en-Y end-to-side procedure to be provided six months after the Sleeve Gastrectomy. Patients are then in a surgically safer position for the full Gastric Bypass surgery. However, some patients do not need the Roux-en-Y end-to-side procedure, as they successfully manage to control their weight loss through medical supervision.