Entrained cryogenic droplet transfer method and cryosurgical instrument

A cryogenic apparatus comprising:

• a coolant means for producing cryogenic droplets entrained in a carrier gas, the coolant means comprising:
• a housing having an inlet port for receiving the carrier gas having a first temperature and pressure and an outlet port coupled to the probe housing;
• and
• a condenser extending into the housing and having an outer surface exposed to the carrier gas, the outer surface of the condenser having a second temperature being less than the saturation temperature of the carrier gas such that a cryogenic liquid condensate forms on the outer surface, the condenser having a distal end being shaped such that the cryogenic liquid condensate drains off the distal end as entrained cryogenic droplets, the distal end of the condenser being positioned relative to an inlet nozzle of the outlet port such that the entrained cryogenic droplets are transported in the carrier gas from the housing via the outlet port;
• and
• a probe comprising a cold-tip for cooling contained objects and an elongated probe housing having a distal end closed by the cold-tip and a proximal end coupled to the coolant means such that the carrier gas passed through the probe housing, the entrained cryogenic droplets being transported by the carrier gas to their distal end of the probe where the droplets are deposited for cooling the tip.

A cryogenic apparatus comprising:

• a coolant means for producing cryogenic droplets entrained in a carrier gas, the coolant means comprising:
• a housing having an inlet port for receiving the carrier gas having a first temperature and pressure and an outlet port coupled to the probe housing;
• a condenser extending into the housing and having an outer surface disposed to the carrier gas, the outer surface of the condenser having a second temperature being less than the saturation temperature of the carrier gas such that a cryogenic liquid condensate forms on the outer surface, the condenser having a distal end being shaped such that the cryogenic liquid condensate drains off the distal end as entrained cryogenic droplets, the distal end of the condenser being positioned relative to an inlet nozzle of the outlet port such that the entrained cryogenic droplets are further atomized to a desired drop size and are transported in the carrier gas from the housing via the outlet port;
• and
• a heater coil connected to the condenser for producing a thermal gradient along the outer surface of the condenser to control the rate of production of the cryogenic liquid condensate;
• and
• a probe comprising a cold-tip for cooling contacted objects and an elongated probe housing having a distal end closed by the cold-tip and a proximal end coupled to the coolant means such that the carrier gas passes through the probe housing, the entrained cryogenic droplets being transported by the carrier gas to their distal end of the probe where the droplets are deposited for cooling the tip.

A cryogenic apparatus comprising:

• a coolant means for producing cryogenic droplets entrained in a carrier gas, the coolant means comprising;
• a housing having an inlet port for receiving the carrier gas having a first temperature and pressure and an outlet port coupled to the probe housing;
• a condenser extending into the housing and having an outer surface disposed to the carrier gas, the outer surface of the condenser having a second temperature being less than the saturation temperature of the carrier gas such that a cryogenic liquid condensate forms on the outer surface, the condenser having a distal end being shaped such that the cryogenic liquid condensate drains off the distal end as entrained cryogenic droplets, the distal end of the condenser being positioned relative to an inlet nozzle of the outlet port such that the entrained cryogenic droplets are further atomized to a desired drop size and are transported in the carrier gas from the housing via the outlet port;
• and
• a heater coil connected to the condenses for producing a thermal gradient along the outer surface of the condenser to control the rate of production of the cryogenic liquid condensate;
• a probe comprising a cold-tip for cooling contacted objects and an elongated probe housing having a distal end closed by the cold-tip and a proximal end coupled to the coolant means such that the carrier gas passed through the probe housing, the entrained cryogenic droplets being transported by the carrier gas to the distal end of the probe where the droplets are deposited for cooling the cold-tip;
• and
• a temperature sensor embedded in the cold-tip and providing a signal for controlling electric power to the heater coil to produce a preprogrammed cold-tip temperature versus time profile.