US 12,458,424 B2
Stabilizing pressure in cryogenic devices
Eric Theodore Johansson, Dublin, CA (US)
Assigned to Pacira CryoTech, Inc., Tampa, FL (US)
Filed by Pacira CryoTech, Inc., Tampa, FL (US)
Filed on Sep. 8, 2023, as Appl. No. 18/243,860.
Application 18/243,860 is a continuation of application No. 17/102,757, filed on Nov. 24, 2020, granted, now 11,779,383.
Claims priority of provisional application 62/943,017, filed on Dec. 3, 2019.
Prior Publication US 2024/0065745 A1, Feb. 29, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. A61B 18/02 (2006.01); A61B 18/00 (2006.01)
CPC A61B 18/02 (2013.01) [A61B 2018/00041 (2013.01); A61B 2018/0047 (2013.01); A61B 2018/00744 (2013.01); A61B 2018/0262 (2013.01); A61B 2018/0293 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A cryogenic device comprising:
a cryogen source including a pressurized cryogen;
a cryogen pathway configured to direct the cryogen toward a needle probe comprising one or more needles, wherein the cryogen is configured to deliver cryotherapy to a target tissue via the one or more needles;
a heater;
a pressure sensor; and
a processor configured to:
receive a first flow rate value, wherein the first flow rate value corresponds to an expected average mass flow rate of a cryogen through a first needle probe of the cryogenic device during a cryotherapy treatment cycle;
determine, based on the first flow rate value, a first target heater power to be applied to the heater associated with the cryogenic device for a first treatment cycle, wherein the heater is configured to heat the cryogen;
receive pressure data from the pressure sensor of the cryogenic device for the first treatment cycle;
apply the first target heater power to the heater during the first treatment cycle in response to the pressure data so as to heat the cryogen and stabilize pressure within the cryogenic device during or after the first treatment cycle;
determine a first pressure of the cryogenic device prior to a cooling cycle of the first treatment cycle;
determine a second pressure of the cryogenic device prior to a cooling cycle of a second treatment cycle; and
calculate a second target heater power for the second treatment cycle, wherein the second target heater power is calculated at least in part by:
adjust the first target heater power upward when the second pressure is lower than the first pressure; or
adjust the first target heater power downward when the second pressure is greater than the first pressure.