抄録
To estimate the decompression effect and the degree of elimination of constricting mechanism of the sphincter of Oddi in transduodenal sphincteroplasty, the present study was carried out using eighty rabbits.
After wedge-resection of the sphincter Oddi was made longitudinally in half of itslength (5-6 mm) or whole through transduodenal approach, biliary pressure, intraduodenal pressure, terminal choledochal pressure, and electrical activity of the Oddi's muscle were studied.
The results were summarized as follows;
1) At fast and rest, the biliary pressure and the intraduodenal pressure were 61.8±8.8 mmH2O and 23.4±3.3 mmH2O respectively showing a pressure gradient of 40 mmH2O approximately. Terminal choledochal pressure gave 81.6±12.9 mmH2O superimposed on by a 3.6±0.3 cycles/min contraction of Oddi's muscle in its pressure curve.
2) In 50% sphincter-resected group, biliary pressure resulted in a slight of 7.7±4.2% and that of terminal choledochal pressure 21.3±6.7%. Occurrence of Oddi's contraction also decreased to 2.4±0.3 cycles/min.
3) In 100% sphincter-resected group, biliary and terminal choledochal pressure decreased markedly giving a value of 30.1±6.6% and 40.8±8.0% respectively. Oddi's contraction disappeared completely in all cases and the gradient maintained between the biliary and intraduodenal pressure was only about 20 mmH2O.
4) By administration of morphine a pressure rise was found by about 20% in 50% sphincter-resected group, whereas no pressure change was observed in 100% sphincter-resected group.
5) In the electrical activity of the sphincter of Oddi, the spike discharge observed preoperatively was totally disappeared and no response was found even in administration of neostigmin.
The results indicate that sphincterotomy or incomplete sphincteroplasty is not a surgical operation satisfactory for biliary drainage or decompression.
On the contrary it appears that complete sphincteroplasty is an effective means for decompression and destruction of sphincteric mechanism of the muscle of Oddi.
