EXPERIMENTAL AND CLINICAL STUDY OF UPPER ESOPHAGEAL RECONSTRUCTION

To establish a reliable anastomosis after cervicothoracic esophagectomy, a different type of narrow gastric tube was made with a surgical stapler. This new type of gastric tube was made along the greater curvature of the stomach and is 3 cm wide at the center and 5 cm wide at the tip (anastomosis site) . In the present study, length, wound healing, and viability of the narrow gastric tube was experimentally and clinically examined and compared with those of the whole gastric tube.<BR>The extension rate was calculated by comparing the length of the narrow gastric tube with that of the intact stomach in dog experimental models ( n =12) . The blood flow volume at several distances from the pylorus was measured by Laser Doppler velocimetry. The blood flow volume of the narrow gastric tube was compared with that of the whole gastric tube. In addition, the reduction rate of the gastric tube was calculated by comparing the length before and after the seromuscular suture was applied. Histopathologic examination of the suture line made with the stapler along the tube, was performed at 3, 5, 7 and 14 days after surgery (n = 20) . In addition, a pressure tolerance test was performed (n = 31) .<BR>In seven patients, blood flow and length of the narrow gastric tube were compared with those of the whole gastric tube. In addition, the extension rate of the narrow gastric tube was measured.<BR>In the dog experimental model, the narrow gastric tube was significantly longer than the whole gastric tube (26.8±3.4 cm and 19.9±1.7 cm, respectively ; P <0.01) . The extension rate was 34.5±9.6%. The blood flow volume was 3.69±0.48 volts at the tip of the narrow gastric tube and 2.58±0.32 volts at the tip of the whole gastric tube (P <0.01) . The reduction rate after seromuscular sutures was 7.7±0.8%. Histopathological examination showed that submucosal vascularization and granulation after necrosis of the mucosa occurred by the 5th day, and that the submucosal and muscular layers became stratified, followed by fibrosis and submucosal vascular connections, 7 days after surgery. On the 14th day, advanced fibrosis and epithelized mucosa was seen. Seven days after surgery, pressure resistance with and without seromuscular suture was 176.1±29.8mmHg and 120.0±26.6mmHg, respectively (P <0.01) . On the 14th day, however, pressure resistance with and without seromuscular suture were almost identical (231.4±24.1mmHg and 247.8±16.8mmHg, respectively) .<BR>In patients, the length of the narrow gastric tube and the whole gastric tube were 38.2± 3.2cm and 26.4±1.9cm, respectively (P <0.01) . The extension rate was 39.6±5.1%. The blood flow volume of the narrow gastric tube 25cm from the pyloric ring was significantly higer than that of the whole gastric tube (P <0.01) . However, the blood flow volume of the narrow gastric tube 35cm from the pyloric ring was 3.66±0.23 volts compared with 3.64±0.01 volts at the tip of the whole gastric tube.<BR>These results indicate that the narrow gastric tube is superior with respect to length extension and viability compared with the whole gastric tube, and is suitable for reconstruction after cervicothoracic esophagectomy. Results of pressure resistance measurements of the narrow gastric tube suggest that adequate early postoperative decompression is necessary when this surgical technique is employed in clinical practice.