Gastric emptying scan after distal subtotal gastrectomy: Differences between Billroth I and II and predicting the presence of food residue at endoscopy.

Purpose: We investigated whether gastric emptying scans (GESs) showed different emptying patterns between patients after different types of laparoscopic distal subtotal gastrectomies. We also investigated whether the presence of food residue via endoscopy can be predicted by GESs. Materials and Methods: We retrospectively enrolled patients who had GESs within postoperative week 1 after a Billroth I or Billroth II operation. Diabetic patients were excluded. GESs were done with a solid test meal. Percent emptying at each scan time was analyzed. The presence of food residue in the stomach and gastrointestinal symptoms at the outpatient clinic were also analyzed. Results: In total, 46 patients were enrolled (Billroth I: Billroth II = 21:25). Sixteen patients underwent a second GES (postoperative 3-6 months). Both groups showed delayed gastric emptying at the postoperative 1 week scan, but group I showed much slower emptying. However, this difference disappeared by the second scan. Based on endoscopies conducted 6 months after the operation, 73.2% of patients had significant amounts of food residue, which hindered an accurate evaluation. The proportion of patients with food residues did not differ between the groups. Receiver Operating Characteristic (ROC) curve analysis revealed that a cut-off value of ≤ 30% emptying at 100 min and 120 min in postoperative 3-6 month scans was both highly sensitive and specific for predicting the presence of food residue (90.91% and 75% for 100 min and 91.67% and 75% for 120 min, respectively). Conclusions: GESs within a week after distal subtotal gastrectomy show slower emptying of Billroth I than II. At a ≤ 30% emptying threshold, a GES can predict subtotal gastrectomy patients who might have a significant amount of food residue in their stomach even after following typical fasting instructions to prepare endoscopy.