Application value of quantitative computed tomography for evaluation of changes in abdominal fat after laparoscopic Roux-en-Y gastric bypass in obese patients

Abstract

Objective To evaluate the application value of quantitative computed tomography for evaluation of changes in abdominal fat after laparoscopic Roux-en-Y gastric bypass in obese patients. Methods The retrospective and descriptive study was conducted. The clinical data of 52 obese patients who underwent laparoscopic Roux-en-Y gastric bypass in the Third Medical Center of Chinese PLA General Hospital from March 2011 to February 2012 were collected. There were 24 males and 28 females, aged (43±9)years, with the range of 23-62 years. All the 52 patients underwent laparoscopic Roux-en-Y gastric bypass. Observation indicators: (1) surgical and postoperative conditions; (2) changes in anthropometric indices; (3) follow-up. Follow-up using outpatient examination was performed to detect complications of patients at 1, 3, 6, 12 months after surgery up to February 2013. Measurement data with normal distribution were represented as Mean±SD, repeated measurement data were analyzed using repeated ANOVA. Count data were represented as absolute numbers. Results (1) Surgical and postoperative conditions: all the patients underwent laparoscopic Roux-en-Y gastric bypass successfully, without conversion to open surgery. The volume of intraoperative blood loss, operation time, and duration of hospital stay were (25±11)mL, (78±14)minutes, and (11±2)days. (2) Changes in anthropometric indices: the body mass index (BMI), fat mass, free fat mass, total abdominal fat volume (TAFV), total subcutaneous fat volume (TSFV), and total visceral fat volume (TVFV) of all the 52 patients were (31.8±1.8)kg/m2, (39.4±4.1)kg, (50.2±6.0)kg, (11 703±3 899)cm3, (7 418±2 969)cm3, and (4 314±1 692)cm3 before surgery, (28.5±1.4)kg/m2, (33.0±1.1)kg, (49.7±4.6)kg, (11 016±3 713)cm3, (7 044±2 970)cm3, (3 969±1 443)cm3 at 3 months after surgery, (27.1±1.7)kg/m2, (30.2±1.3)kg, (45.4±3.1)kg, (9 406±4 452)cm3, (6 442±3 307)cm3, and (2 964±1 694)cm3 at 6 months after surgery, (24.4±2.4)kg/m2, (32.6±1.1)kg, (48.6±2.7)kg, (7 612±3 029)cm3, (5 623±2 650)cm3, and (1 826±360)cm3 at 12 months after surgery, respectively, there were significant differences in the changes of these indices (F=130.2, 30.3, 4.9, 25.6, 11.9, 16.5, P 0.05). The BMI, fat mass, TAFV, and TVFV at 6 months after surgery had significant differences compared with those before surgery (P 0.05). The BMI, fat mass, TAFV, TSFV, and TVFV at 12 months after surgery had significant differences compared with those before surgery (P 0.05). (3) Follow-up: all the 52 patients have completed the follow-up after surgery and the remission number of obesity was 35. No complications such as anastomotic hemorrhage, obstruction, or anastomotic leakage occured in all the 52 patients. Conclusion Laparoscopic Roux-en-Y gastric bypass can reduce abdominal visceral fat significantly, while quantitative computed tomography can help to evaluate the distribution of abdominal visceral fat accurately. Key words: Obesity; Gastric bypass surgery; Quantitative computed tomography; Visceral fat; Laparscopy