Obesity surgery improves metabolic dysfunction-associated steatotic liver disease and type 2 diabetes - MRI and biochemical analysis of liver and pancreas.

Background: This study evaluated changes in metabolic dysfunction-associated steatotic liver disease (MASLD), type 2 diabetes mellitus, liver volume, liver/pancreas fat in patients after obesity surgery. Methods: Magnetic Resonance Imaging (MRI) measured liver volume/fat and pancreas fat in 31 patients with laparoscopic sleeve gastrectomy (LSG, N = 20) or Roux-en-Y gastric bypass (RYGB, N = 11) preoperatively and at 3- and 12-month follow-up. Clinical data and blood values were taken concomitantly to calculate Non-alcoholic fatty liver disease (NAFLD) score. Results: The percentage total weight lost (17.5 % ± 5.4 % at 3 months, 28.4 % ± 8.3 % at 12 months) and percentage excess weight lost (40.0 % ± 11.8 % at 3 months, 65.0 % ± 18.8 % at 12 months) were significant. Liver volume decreased from 2378.3 ± 514.5 cm3 to 1928.7 ± 333.5 cm3 at 3 months (p < 0.001) and 1685.0 ± 310.9 cm3 at 12 months (p < 0.001) after surgery. Liver fat percentage decreased from 16.7 % ± 10.3 % to 8.7 % ± 5.4 % at 3 months (p < 0.001) and 5.2 % ± 3.6 % at 12 months (p < 0.001). Pancreatic fat percentage showed a reduction from 14.8 % ± 5.5 % to 10.9 % ± 4.9 % at 3 months (p = 0.007) postoperatively. NAFLD score improved from preoperative measurements to 12 months postoperatively (-0.89 ± 1.54 vs. -1.77 ± 1.25, p < 0.019). Preoperatively, 22 of 31 (71 %) patients had advanced/intermediate scores; 12 months postoperatively only 12 (39 %) remained (p = 0.044). No significant differences between LSG and RYGB were found regarding goal parameters. Conclusion: Obesity surgery reduced liver volume, type 2 diabetes, fat content of liver and pancreas and improved indicators of MASLD. No significant difference in outcome between operation methods could be established.