| 摘要 |
<p>PURPOSE: To provide an improved stent introducing device used as an accessory for the artery angioplasty by enabling a stent to be released from an end cap at the time of balloon expansion. CONSTITUTION: Stent 24 has half-rigid elastic tube 4 formed out of material suitable for being left in a blood vessel over a long term. Also, the tube 4 in a relaxed and non-expanded state has a relatively small diameter and takes an approximately cylindrical form having spiral cross section. One peripheral end of the tube 4 has a holding shelf type projection 6, and when the stent 24 expands, the cylindrical tube 4 falls in such a state as partly unwound and becomes a cylindrical body having a large diameter. When the cylindrical body well expands, the holding shelf type projection 6 is engaged with the internal part of a spiral part 2, thereby locking the cylindrical body in an expanded state. Also, when a balloon 20 expands, the stent 24 radially expands, and caps 26 and 28 are radially and axially energized like an umbrella from the center of the balloon 20. As a result, the stent 24 is caused to retreat and released.</p> |
