Massive bleeding is a lethal complication of portal hypertension. Portal decompression has usually been used to as a preventive measure for many years. However

in Japan

shunt operations are rarely performed now and are gradually replaced by portoazygos vein interruption.Portoazygos vein interruption operation consists of two main types

transabdo-minal and transthoracic

the latter first reported by Sugiura in Japan. In our college the transabdominal route was practiced from 1966

but since 1977 has been replacedby transthoracic route. A total of 58 transabdominal cases and 35 transthoracie cases have now been done altogether. The transthoracic procedure is a modification of the Sugiura operation

omitting esophageal transection

anterior trank vagotomy and pyloroplasty. The results of this modified operation appeared better than the transabdominal procedure.However

topographical anatomical study of the portoazygos system made one believe that it is very difficult to perform a complete interruption of the coronary venous system especially through the transabdominal route.