[Functional recovery of Oddi's sphincter after balloon dilatation of the papilla of Vater. An experimental study in rabbits].

INTRODUCTION

Balloon dilatation of the papilla of Vater is used to treat biliary lithiasis. The results and complications rate of this technique are excellent. Published data indicate that this procedure does not significantly alter the physiology of the sphincter of Oddi and that normal function is maintained. Papillary balloon dilatation would therefore provide an advantage over other techniques in which sphincteric function is abolished. The objective of this study was to evaluate the functional status of the sphincter of Oddi after balloon dilatation of the papilla of Vater.

MATERIAL AND

METHODS

Twenty-four New Zealand albino rabbits were used. All animals underwent laparotomy and duodenotomy with balloon dilatation of the papilla of Vater. Manometric study of the biliary tract and of the sphincter of Oddi was also performed before, shortly after, and 21 days after dilatation. Biliary and sphincter of Oddi pressures and phasic activity of the sphincter (frequency, amplitude and duration of waves) were used as measuring variables for each of the stages of the experiment.

RESULTS

Papillary balloon dilatation immediately provoked substantial sphincter relaxation. Comparison of the values of basal biliary and sphincter of Oddi pressures with those found 21 days after dilatation showed no statistically significant differences. No significant differences were found when the variables related to phasic activity of the sphincter (frequency, amplitude and duration) were compared between the distinct phases of the experiment.

CONCLUSIONS

The results of the present study suggest complete recovery of sphincter function 21 days after balloon dilatation.