Automated system for the radiation treatment of a desired area within the body of a patient

1. In a system comprising a microprocessor-controlled transfer device and a separate catheter for intraluminal treatment of a selected site in a body of a patient by at least one treating element advanced from a removable treating element cartridge received in the transfer device into a lumen of the separate catheter by means of pressurized fluid controlled by a fluid control switch moveable between send and return positions, a safety interlock for preventing both the disassembly of the system unless the treating element resides in the treating element cartridge and the actuation of the fluid control switch unless the system is assembled, the safety interlock comprising:

a first lock removeable from a first position to a second position only if both the catheter and treating element cartridge are secured to the transfer device, the first lock blocking movement of the fluid control switch to the send position when in the first position and preventing disassembly of either the catheter or the treating element cartridge from the transfer device when in the second position, the fluid control switch further locking the first lock in its second position when the fluid control switch is in the send position.

2. The safety interlock of claim 1 wherein the first lock comprises:

a spring having two arms, each arm being engaged by one of the catheter or the treating element cartridge when attached to the transfer device; and

a slidable switch including a yoke that is moveable from a first position to a second position to capture the arms of the spring and lock both the catheter and treating element cartridge to the transfer device only if each arm of the spring is engaged by one of the catheter and treating element cartridge, each arm of the spring independently capable of blocking movement of the yoke from the first position to the second position if not engaged by one of the catheter or treating element cartridge.

3. The safety interlock of claim 2 wherein the slidable switch includes a shoulder and the fluid control switch includes an arm that engages the shoulder when the yoke is in the second position and the fluid control switch is in the send position.

4. A safety interlock of claim 1 further comprising:

a gate mechanism moveable between open and closed positions by the fluid control switch to respectively permit or prevent the treating element from moving out of the treating element cartridge when subjected to a pressurized fluid; and

a solenoid to lock the gate mechanism in the open position, the solenoid disengaging the gate mechanism to permit it to close only when the treating element resides in the treating element cartridge.

5. The safety interlock of claim 1 further comprising:

a photo interrupter that is triggered when the first lock is moved to the second position to lock the treating element cartridge and the catheter to the transfer device, the triggered photo interrupter generating a signal that is transmitted to the microprocessor to permit the treatment to continue.

6. The safety interlock of claim 4 further comprising a series of photo interrupters associated with the fluid control switch to detect the position of the fluid control switch and generate a signal sent to the microprocessor to permit the treatment to continue in accordance with the position of the fluid control switch.