High-pressure balloons can be used to transfer heat or cold, either into or out
of a vessel or cavity and can be readily inflated and deflated so as to provide
easy low profile entry and exit while providing large diameters and surface area
when inflated in use. They serve as a very good medium because their ultra thin
walls provide a relatively high rate of heat transfer. The balloons also provide
intimate contact with the area being treated, conforming to curves and irregularities
in the surface of a vessel. For example, in cryosurgery of the prostate, a specially
designed fluid-circulating high-pressure balloon catheter is inserted in the urethra1.
The long thin-walled balloon covers the entire length of the urethra up into the
bladder to protect the urethra and sphincter muscles from being damaged by the extreme
cold produced by cryoprobes inserted in the prostate gland. Flexibility, conformability
and high heat transfer rates are critical to protect tissue and muscles in the application.
Heat transfer catheters are made in various sizes to accommodate
different devices and anatomy.
Footnote
1 U.S. Patent No. 5,624,392, Saab, "Heat Transfer Catheters and Methods
of Making and using Same", April 29, 1997.