Putnam Plastics Corp. has developed a line of polymer marker bands for fluoroscopic illumination of catheter tips used in minimally invasive medical procedures. The plastic bands eliminate the need for traditional gold or platinum marker bands, thus reducing material costs, and adhere more easily to catheter shaft tips.
Essentially short, thin-wall tubes, marker bands are placed on the tips of catheter shafts to provide visibility under fluoroscopy. This allows surgeons to precisely locate catheter features deep within the body for deployment of balloons, stents and other devices in blood vessels.
The manufacture of metal marker bands entails a multistep forming process that is costly and time consuming. Moreover, quality controls to ensure sufficient mechanical bonding between dissimilar materials can be significant.
Putnam’s new marker bands are made from tungsten-filled polymers, such as nylons, urethanes and thermoplastic elastomers. The bands are customised using the same polymer specified for the catheter shaft to allow heat bonding of the band for a more-secure assembly. Tungsten loadings range from 65% to 80% by weight to meet radiopacity requirements. Using proprietary co-extrusion technology, Putnam applies an unfilled polymeric outer surface to these bands similar to the surface of the catheter shaft to ensure minimal trauma to blood vessel walls.
Marker bands with inside diameters from 0.356 to 5.080 mm and wall thicknesses from 0.051 to 0.762 mm are available from the company, which is headquartered in Dayville, CT, USA.Norbert Sparrow