Cryosurgery - Technical information

How does cryosurgery work?

The basic principle of current cryosurgery systems is based on forcing gas under pressure of between 600 and 800psi between the inner and outer tubes of the cryoprobe. The gas is released through a small opening into a chamber at the tip of the probe. As the pressurized gas is released into the chamber, it expands and results in a rapid drop in temperature. This is referred to as the Joule-Thompson effect and results in an ice ball forming at the uninsulated tip of the probe. The temperature can reach -70°C and the size of the ice ball can range from 3.5mm to 10mm depending on the amount of tube that is not insulated. Because these units are a closed system, no gas escapes from the cryoprobe.