CATHETER FOR RADIATION THERAPY

摘要

A catheter for radiation therapy comprising: a centering mechanism for irradiating a blood vessel wall with a homogeneous dose; and a perfusion mechanism for perfusing peripheral vessels with blood at all times of centering. The catheter has no roughness on its surface so that it causes neither resistance in moving in the vessel nor a danger of damaging the vessel inner face. In an expandable portion located at the leading end of the catheter, a protrusion is formed in the portion of a specific region at the expanded time by the elasticity difference between two kinds of materials of different elasticities. In the expandable portion, there are arranged a low-elasticity portion and a high-elasticity portion, the latter being expanded more largely than the former to make the protrusion when a pressure is applied. Alternatively, the catheter is given a two-layer structure of inner and outer layers of two kinds of materials of different elasticities, and a cavity is formed in the layer of the lower elasticity so that a portion, as corresponding to the cavity, of the layer of the higher elasticity may protrude when a pressure is applied.