Gastroesophageal reflux disease (GERD) is one of the most common chronic conditions that can affect one's quality of life. Laparoscopic sleeve gastrectomy (LSG) has become a popular technique and currently is the most frequently practiced surgical operation to treat obesity today. However, the prevalence of GERD following SG can be fairly high. Several studies have noted an incidence between 6% and 47%.

The angle of His is important for the maintenance of esophageal anti-reflux ability, and prevent GERD. Most SG operating consensus recommends surgeons should stay at least 1 cm away from the angle of His. However, on consensus was reached about the pre-cardial fat pad should be routinely dissected or not to avoid leaving behind a large fundus consensus.

The investigators propose to perform a prospective randomized controlled study to dissect the pre-cardial fat pad or not in obese patients followig sleeve gastrectomy to prevent GERD.

Gastroesophageal reflux disease (GERD) is one of the most common chronic conditions that can affect one's quality of life. Laparoscopic sleeve gastrectomy (LSG) has become a popular technique and currently is the most frequently practiced surgical operation to treat obesity today. However, the prevalence of GERD following SG can be fairly high. Several studies have noted an incidence between 6% and 47%.

The angle of His is important for the maintenance of esophageal anti-reflux ability, and prevent GERD. Most SG operating consensus recommends surgeons should stay at least 1 cm away from the angle of His. However, on consensus was reached about the pre-cardial fat pad should be routinely dissected or not to avoid leaving behind a large fundus consensus.

The dissection of pre-cardial fat pad is helpful to fully expose the gastric fundus, to accurately judge the distance between the incision line and the esophagus, and to help the suture embedding of the incision line. However, the disadvantages might increase the rate of GERD. While retaining the pre-cardial fat pad may contribute to the reduction of GERD rate. However, it might not be conducive to the judgment of cutting distance to the esophagus and the procedure of suture embedding. Futhermore, there may be gastric fundus residue during SG.

The investigators propose to perform a prospective randomized controlled study to dissect the pre-cardial fat pad or not in obese patients followig sleeve gastrectomy to prevent GERD.

Inclusion Criteria:

• BMI ≥ 32.5 kg/m2 with or without T2DM;
• 27.5 kg/ m2 < BMI < 32.5 kg/m2 with T2DM but failed conservative treatment and combined with at least two metabolic diseases or comorbidities;
• Duration of T2DM ≤15 years with fasting Cpeptide ≥ 50% of normal lower limit
• Waist circumference: male ≥ 90 cm, female ≥ 85 cm
• Age within 16~65 years old

Exclusion Criteria:

• GERD preoperatively
• Hiatus hernia approved by gastroscopy preoperatively
• Pregnancy;
• A history of mental illness and neurological disease;
• The patient refuses surgery;
• Combined with pituitary tumor;
• Long-term use of antidepressant drugs;
• Long-term use of immunosuppressants;
• Situations in which the investigator or other examiner considers from the enrolled study that there are good reasons for nonconformity: if there are potential inconsistencies with the clinical protocol