Impact of resected gastric volume on postoperative weight loss after laparoscopic sleeve gastrectomy for morbid obesity. Observational study with a mathematical method to approximate the calculation of the resected gastric volume after a sleeve gastrectomy and see the outcome on weight loss.

Inclusion Criteria:

• BMI over 60 kg/m2 in high-risk patients,
• BMI between 50 and 60 kg/m2 in nondiabetic patients,
• BMI between 40 and 50 kg/m2 in patients refusing a complex procedure like Roux-en-Y gastric bypass,
• patients with severe gastric inflammatory disease and H. pylori infection,
• patients with previous abdominal surgery involving the intestines, and young patients refusing gastric banding

Exclusion Criteria:

• severe and documented gastroesophageal reflux disease
• previous gastric surgery.

final group from which data have been considered 92 patients (47females and 45 males)