title: Evolution of Liver Steatosis Quantified by MR Imaging and MR Spectroscopy, in Morbidly Obese Patients Undergoing Sleeve Gastrectomy: Short-Term Outcomes.
abstract: Currently, the standard procedure used to evaluate hepatic steatosis is the liver biopsy. This is an invasive practice that presents inherent risks. Increasing evidence suggests that magnetic resonance imaging (MRI) and MR spectroscopy (MRS) may represent an accurate method to determine the hepatic lipid content. The aim of this study was to evaluate the effect of sleeve gastrectomy on liver steatosis, quantified by MRI and MRS.
  
  
  
  A prospective observational study of patients undergoing laparoscopic sleeve gastrectomy was performed. All patients underwent a MRI and a MRS study 2 weeks before the intervention and 6 months after the surgery. Anthropometric, biochemical, and radiological parameters were analyzed.
  
  
  
  Twenty-three patients were included, 21 females and 2 males, with a mean age of 47.6 ± 10.6 years and mean pre-op BMI 47.6 ± 6.7 Kg/m2. Six months after surgery, mean BMI was 32.2 ± 5.1 Kg/m2, with a mean excess weight loss of 68.2 ± 18.6%. Mean preoperative hepatic volume was 1999.9 ± 436.2 ml and 6 months after surgery it decreased to 1568 ± 170.3 ml (p = 0.005). Mean preoperative percentage of lipid content was 14.2 ± 15.4% and 6 months after surgery, it decreased to 4.3 ± 3.2% (p = 0.007). A significant reduction of steatosis grade was observed, with disappearance of preoperative steatosis in 54.9% of the patients.
  
  
  
  Six months after sleeve gastrectomy, a significant reduction of liver steatosis is observed, as demonstrated by reduction in the percentage of intrahepatocitary lipids and liver volume, determined by MRS and MRI. These imaging techniques can be considered as noninvasive, accurate methods for monitoring liver steatosis in morbidly obese patients undergoing bariatric surgery.
authors.affiliation: Department of Radiology, Hospital Lluis Companys, Xativa, Valencia, Spain.
authors.forename: María Engracia
authors.initials: ME
authors.lastname: Alsina
authors.affiliation: Department of Surgery, Bariatric Surgery Unit, University Hospital Rey Juan Carlos, Gladiolo s/n, 28933, Madrid, Spain. jruiztovar@gmail.com.
authors.forename: Jaime
authors.initials: J
authors.lastname: Ruiz-Tovar
authors.affiliation: Magnetic Resonance Department, Inscanner SL, Alicante, Spain.
authors.forename: Angela
authors.initials: A
authors.lastname: Bernabeu
mesh_terms: D000328:Adult; D005234:Fatty Liver / Q000000981:diagnostic imaging / Q000209:etiology; D005260:Female; D005743:Gastrectomy / Q000379:methods*; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000150:complications / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery; D011446:Prospective Studies
keywords: Liver steatosis; Magnetic resonance imaging; Sleeve gastrectomy; Spectroscopy