radiopaque marker bands
A catheter having a radiopaque marker band disposed on the distal end of the catheter allows quick, simple and reliable identification of a precise location of one or more bores within the catheter using X-ray imaging techniques. In addition, the presence of a marker band can help a practitioner to appreciate whether a catheter has changed position during insertion or during the course of catheter use.
Radiopaque markers are generally composed of a cylindrical polyurethane material that is impregnated with, or otherwise comprises, one or more radiopaque materials, such as metal, metal flakes, metal powder, ceramics, Barium Sulfate (BaSO4), Bismuth Subcarbonate (Bi2O2(CO3)), Bismuth Trioxide (Bi2O3) and other suitable radiopaque materials. The particular radiopaque material used will typically be selected based on the type of imaging technique utilized to identify the marker’s location.
In a preferred embodiment of the invention, the radiopaque material is imbued in a polyurethane slurry that is then molded or extruded into a band configuration. Once the band is formed, a heat fusion process can be applied to bond the radiopaque marker band to a elongate tube such as a catheter tube 110.
Once the elongate tube and the radiopaque marker band have become contiguous, drainage bores may be formed in the distal end of the elongate tube. In order to maintain the outer diameters of the elongate tube and the marker band, a mandrel or confinement tube may be inserted into the lumen of the elongate tube prior to heat fusion.