TREATMENT CATHETERS WITH THERMALLY INSULATED REGIONS

摘要

Flexible treatment catheters are configured to be inserted into a body lumen or cavity to deliver heated fluid through at least one fluid lumen therein to thermally treat or ablate a targeted site in a biological subject. The flexible treatment catheters can include improved thermally insulated regions comprising a mixture formed of liquid elastomeric (such as a polyurethane) mixture (which transitions to a solid state) and miniaturized hollow plastic bodies positioned between the outer wall of the treatment catheter and the fluid lumen. The thermally insulated region is configured such that, measured ex vivo, the treatment catheter can present a maximum temperature of below about 45°C on the external surface of the outer wall of the treatment catheter when the treatment catheter circulates fluid having an inlet temperature of above or between about 60°-62°C. Alternatively or additionally, the treatment catheter can include an elongated insert positioned in a catheter fluid lumen to inhibit the closure of the lumen after exposure to fluids in the treatment catheter at temperatures sufficient to thermal ablate targeted tissue over a thermal ablation treatment period. The treatment catheter can include a urinary drainage lumen with an elongated insert frictionally engaged therewith, the drainage lumen and insert are configured to provide a fluid volume throughput through the drainage lumen of greater than about 20-25 ml/min during and after (for about 12-72 hours after) a thermal ablation session.