Abstract: A pullback mechanism is provided that includes base block, a clamping retainer, and a sliding retainer. The clamping retainer preferably includes a clamping block and a mechanism for tightening the clamping block against the base block. The sliding retainer preferably includes a retainer carriage on which is mounted a clamping retainer and a mechanism for tightening the clamping retainer against the retainer carriage. In one preferred embodiment, the sliding retainer is mounted on a guide rail that is fixed to the base block. A pullback line attached at one end to the retainer carriage of the sliding retainer and at a second end to a movement imparting mechanism. A control unit controls the operation of the movement imparting mechanism to impart movement to the pullback line. In a further embodiment, a lead screw is provided on the base block and the sliding retainer is moveable coupled to the lead screw via a threaded mounting hole.

Abstract: An apparatus provides in-situ radiation treating utilizing a miniature energy transducer to produce x-rays, wherein the energy transducer includes a Schottky cathode tip. More specifically, the energy transducer includes a transducer body, an anode provided at a first end of the transducer body, and a cathode provided at a second end of the transducer body opposite the anode. The energy transducer is coupled to an energy source by a flexible insertion device. The energy source provides electrical and/or light signals to the energy transducer via the flexible insertion device. Light transmitted from the energy source to the energy transducer by the flexible insertion device is focused on a Schottky cathode tip of the cathode by the optical fiber provided in the hollow core of the anode.

Abstract: An apparatus and method for in-situ x-ray radiation treatment utilizes different types of miniature energy transducers to emit x-rays. Each type of energy transducer includes a transducer body, a cathode provided at one end of the transducer body, and an anode provided at another end of the transducer body. The transducer body, cathode and anode define a cavity that communicates with an evacuation opening. A desired vacuum is achieved and maintained by a dynamic pumping mechanism that draws a vacuum in the cavity via the evacuation opening.

Abstract: A dosimeter for an x-ray brachytherapy system permits in situ monitoring and control of radiation treatment via a miniaturized energy transducer within a human body. The dosimeter comprises a scintillating optical fiber having a distal end which is placed at the treatment site and a proximal end which is coupled to a dosimeter measurement unit. Utilizing energy supplied by an energy source, the miniaturized transducer generates x-ray photons. The scintillating optical fiber absorbs x-ray photons, converts the x-ray photons into light photons, and conveys the light photons to a dosimeter measurement unit. The light photons are converted into an electrical current which is representative of the intensity of the x-ray photons. The dosimeter measurement unit utilizes the electrical current to calculate and display the instantaneous and accumulated radiation dose, and radiation dose parameters are utilized to adjust energy levels, which are sent to the miniature energy transducer.