Delivery system and prescription method for interstitial radiation therapy using enhanced parametric release sterilization techniques
First Claim
1. A method of sterilizing a brachytherapy device comprising the steps of:
- assembling the brachytherapy device by loading a radioactive seed implant into a delivery needle;
arranging a gas permeable safety plug over a distal end of the delivery needle;
inserting a stylet into a proximal end of the needle so that a portion of the stylet extends out from the delivery needle;
positioning the brachytherapy device in a tray by securing the distal end of the delivery needle to the tray and securing the portion of the stylet to the tray so as to resist relative movement of the stylet and the delivery needle;
packaging the brachytherapy device and the tray in a gas permeable package;
exposing the brachytherapy device and the package to a sterilizing gas;
sterilizing the brachytherapy device using a set of process parameters that provide a prescribed level of sterilization; and
parametrically releasing the brachytherapy device from the sterilization process.
7 Assignments
0 Petitions
Accused Products
Abstract
A process is provided for sterilizing brachytherapy devices with Ethylene Oxide gas and releasing the devices on a parametric release basis. Devices that can be sterilized with this process include interstitial radiation seed strand implants and the needles used for implantation. In order to be sterilized effectively by EtO gas, the devices are constructed such that surfaces not readily infused with EtO gas are made to be gas permeable, and will not retain the gas after the sterilization process. Performance qualification of the sterilization process is performed through physical and microbiological studies, and set of established physical process parameters. Maintaining the physical process parameters in subsequent sterilization cycles will consistently yield the desired sterility assurance level without having to test the devices for sterility.
45 Citations
39 Claims
-
1. A method of sterilizing a brachytherapy device comprising the steps of:
-
assembling the brachytherapy device by loading a radioactive seed implant into a delivery needle; arranging a gas permeable safety plug over a distal end of the delivery needle; inserting a stylet into a proximal end of the needle so that a portion of the stylet extends out from the delivery needle; positioning the brachytherapy device in a tray by securing the distal end of the delivery needle to the tray and securing the portion of the stylet to the tray so as to resist relative movement of the stylet and the delivery needle; packaging the brachytherapy device and the tray in a gas permeable package; exposing the brachytherapy device and the package to a sterilizing gas; sterilizing the brachytherapy device using a set of process parameters that provide a prescribed level of sterilization; and parametrically releasing the brachytherapy device from the sterilization process. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method of sterilizing at least one brachytherapy device, comprising steps of:
-
providing an open, sealable diffusion bag to contain said at least one brachytherapy device; receiving a tray including the at least one brachytherapy device comprising a radioactive seed implant arranged in a delivery needle and a stylet arranged at least partially in the delivery needle so that a portion of the stylet extends out from the delivery needle; wherein the delivery needle is secured to the tray and the portion of the stylet is secured to the tray so as to resist relative movement of the stylet and the delivery needle; placing said at least one brachytherapy device and said tray into an interior of the open diffusion bag; evacuating air from the diffusion bag; sealing the diffusion bag; positioning the diffusion bag in a chamber of a sterilizer having a ventilation system for removal of an exhaust gas from the chamber; providing a sterilizing atmosphere in the interior of the diffusion bag by releasing into the diffusion bag ethylene oxide gas at a concentration sufficient to act as a sterilant; heating ethylene oxide gas to an appropriate temperature; maintaining the temperature of the ethylene oxide gas for a sufficient time to sterilize the at least one brachytherapy device. - View Dependent Claims (7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method of sterilizing a brachytherapy device, the method comprising:
-
providing a gas permeable tray to contain said brachytherapy device; wherein said brachytherapy device comprises a radioactive seed implant arranged in a delivery needle and a stylet arranged at least partially in the delivery needle so that a portion of the stylet extends out from the delivery needle; securing the delivery needle to the tray and the portion of the stylet to the tray so as to resist relative movement of the stylet and the delivery needle; placing said tray into a sealable diffusion bag; sealing the diffusion bag; positioning the diffusion bag in a chamber of a sterilizer having a ventilation system for removal of an exhaust gas from the chamber; providing a sterilizing atmosphere in the interior of the diffusion bag by releasing into the diffusion bag ethylene oxide at a concentration sufficient to act as a sterilant; heating the ethylene oxide to an appropriate temperature; maintaining the temperature of the ethylene oxide gas for a sufficient time to sterilize the brachytherapy device and to complete the sterilization process; conducting a performance qualification of the sterilization process through physical and microbiological studies; extracting from the performance qualification a set of physical process parameters, which will consistently yield the desired sterility assurance level when said set of physical process parameters are maintained; maintaining, monitoring, and recording the physical process parameters through direct analysis during routine processing; and repeating the sterilization process for subsequent brachytherapy devices and releasing the sterilized brachytherapy devices on parametric release. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
-
-
34. A method of sterilizing a brachytherapy device, the method comprising:
-
receiving the brachytherapy device secured to a gas permeable tray, the brachytherapy device including a radioactive seed implant arranged in a delivery needle; receiving a stylet for use with the brachytherapy device; wherein the stylet is secured to the tray; placing said tray into a sealable diffusion bag; positioning the diffusion bag in a chamber of a sterilizer; providing a sterilizing atmosphere in the interior of the diffusion bag by releasing ethylene oxide into the diffusion bag at a concentration sufficient to act as a sterilant; sterilizing the brachytherapy device by controlling an environment of the chamber using a set of process parameters; and parametrically releasing the at least one brachytherapy device from the sterilization process. - View Dependent Claims (35, 36, 37, 38, 39)
-
Specification