Medical devices and related methods, and, more specifically, cryogenic surgical systems and related methods are disclosed. Some example cryogenic surgical systems may include a cryosurgical control unit configured to cool a cryosurgical probe to a temperature colder than a temperature at which flow of cryogenic fluid to the probe is stopped. Some example tank level indicating systems may utilize the pressure of the fluid in the tank and a temperature of the exterior wall of the tank to indicate liquid level.
