Abstract: A miniature x-ray tube has an anode assembly capable of transmitting x-rays through the anode and over a wide angular range. The anode is in the shape of a cone or truncated cone with an axis on the x-ray tube frame axis, formed of low-Z material with high thermal conductivity for heat dissipation. A target material on the anode body is in a thin layer, which may be approximately 0.5 to 5 microns thick. In one embodiment a tube evacuation exhaust port at the tail end of the anode assembly forms a cavity for a getter, with a pinched-off tubulation at the end of the cavity.

Abstract: A radio frequency ID tag, very small in size and with an onboard antenna, is manufactured, tested and applied cost-efficiently. The transmit frequency for the tag is set during manufacture approximately, within a selected range, in a gross tuning step. The gross calibration is based on one or more measured characteristics of electronic componentry on wafers, and based on such measured characteristics, the chips can be grossly calibrated and parallel so that all tags will be within a fairly close tolerance of the target transmit frequency. A second tuning step fine tunes each tag by RF communication to set values of capacitance, resistance, etc., and this can be at the point of application of the tags. Other disclosed aspects of the invention also add to economy of producing the tag and reliability of the tags in service.

Abstract: Methods for connecting electrical potential to an extractor cup at the cathode of a miniature x-ray tube are disclosed. The various connection schemes are designed to form a rugged and conveniently manufacturable connection between the metal extractor cup and one side of the cathode filament, so that the extractor cup shapes the path of electrons as desired en route to the anode of the tube. Some of the disclosed connections involve evaporation of conductive metal or other materials off the filament when the filament is first activated. Others involve applying a paste or paint conductive precursor directly to a base to connect a post and the extractor, the paste being heat-cured after the completion of assembly. Others involve a fine wire or spring strip from one filament post to the walls of the extractor cup. Other schemes include welded or brazed wires or foil, crimping, pinching, swaging and other connections, all made inside the tube enclosure.

Abstract: Methods for connecting electrical potential to an extractor cup at the cathode of a miniature x-ray tube are disclosed. The various connection schemes are designed to form a rugged and conveniently manufacturable connection between the metal extractor cup and one side of the cathode filament, so that the extractor cup shapes the path of electrons as desired en route to the anode of the tube. Some of the disclosed connections involve evaporation of conductive metal or other materials off the filament when the filament is first activated. Others involve applying a paste or paint conductive precursor directly to a base to connect a post and the extractor, the paste being heat-cured after the completion of assembly. Others involve a fine wire or spring strip from one filament post to the walls of the extractor cup. Other schemes include welded or brazed wires or foil, crimping, pinching, swaging and other connections, all made inside the tube enclosure.

Abstract: A radiation therapy system and method, especially for brachytherapy, monitors and verifies dose delivered at a plurality of points at or near the region to be irradiated, integrating verification with radiation delivery. In one procedure, mapping is used to determine the shape and location of the region to be irradiated. A treatment plan is developed using the mapping information and a dose prescription. As radiation is delivered to the target region internally, preferably using an electronic radiation source, the dose received at plural points is monitored and continually fed to a central processor. As needed based on feedback, the system modifies the treatment plan and delivery of radiation accordingly, to arrive substantially at the prescribed dose at all locations in the region. In a modified procedure the treatment is done according to a prescription dose but without a treatment plan by multiple iterations of source pullback and feedback and analysis of dose received in the tissue.

Abstract: A miniature x-ray tube is cooled using a catheter preferably having multiple small lumens for inflow and outflow of coolant. Inflow may be through an outer lumen(s) in a concentric-extrusion catheter, the liquid turning back at the distal end of the catheter to a proximal flow over the anode end of the x-ray tube and through an inner lumen within which the x-ray tube is positioned. A coolant distribution head may engage with the anode end of the x-ray tube, with small orifices so as to distribute coolant essentially evenly over the anode surface. Temperature and flow rate of the inflowing coolant liquid are balanced so as to optimize heat transfer while efficiently carrying coolant through small lumens without the need for high pressures. Some embodiments use the inflation liquid in an applicator balloon as the coolant, with the liquid actively flowing or, in a simplified system, with the liquid static.

Abstract: Methods for connecting electrical potential to an extractor cup at the cathode of a miniature x-ray tube are disclosed. The various connection schemes are designed to form a rugged and conveniently manufacturable connection between the metal extractor cup and one side of the cathode filament, so that the extractor cup shapes the path of electrons as desired en route to the anode of the tube. Some of the disclosed connections involve evaporation of conductive metal or other materials off the filament when the filament is first activated. Others involve applying a paste or paint conductive precursor directly to a base to connect a post and the extractor, the paste being heat-cured after the completion of assembly. Others involve a fine wire or spring strip from one filament post to the walls of the extractor cup. Other schemes include welded or brazed wires or foil, crimping, pinching, swaging and other connections, all made inside the tube enclosure.

Abstract: A miniature x-ray tube is cooled using a catheter preferably having multiple small lumens for inflow and outflow of coolant. Inflow may be through an outer lumen(s) in a concentric-extrusion catheter, the liquid turning back at the distal end of the catheter to a proximal flow over the anode end of the x-ray tube and through an inner lumen within which the x-ray tube is positioned. A coolant distribution head may engage with the anode end of the x-ray tube, with small orifices so as to distribute coolant essentially evenly over the anode surface. Temperature and flow rate of the inflowing coolant liquid are balanced so as to optimize heat transfer while efficiently carrying coolant through small lumens without the need for high pressures. Some embodiments use the inflation liquid in an applicator balloon as the coolant, with the liquid actively flowing or, in a simplified system, with the liquid static.

Abstract: A vaginal brachytherapy applicator is versatile to different anatomies and more comfortable to the patient than prior applicators. An inflatable balloon on a shaft may be inelastic or elastic. In one embodiment the shaft is rotatable relative to the balloon for enabling a ring or band of dose delivery, for versatility in radiation placement. Alternatively, the source can be rotated and pulled back within a stationary shaft. An adjustment is provided for reducing the length of balloon that inflates, to accommodate different anatomies and positions. Although isotope radiation sources can be used in the applicator, an electronic source is preferred, and the system and method include procedures for using the applicator with an electronic source.

Abstract: An applicator designed for use with a miniature electronic x-ray source, having a relatively large guide for the electronic source, is modified by an adapter inserted into the source guide to produce a narrower-diameter guide that will receive a standard afterloader that irradiates with isotopes.

Abstract: Applicators for ionizing radiation therapy and their methods of use are provided for expedient preparation of precise treatment plans and for quantitative assessment of therapy delivered to natural or surgically-created, intra-corporeal cavities or lumina. Feedback capability is provided for timely treatment control and for verification of treatment to plan using sensors on the applicators.

Abstract: Methods for connecting electrical potential to an extractor cup at the cathode of a miniature x-ray tube are disclosed. The various connection schemes are designed to form a rugged and conveniently manufacturable connection between the metal extractor cup and one side of the cathode filament, so that the extractor cup shapes the path of electrons as desired en route to the anode of the tube. Some of the disclosed connections involve evaporation of conductive metal or other materials off the filament when the filament is first activated. Others involve applying a paste or paint conductive precursor directly to a base to connect a post and the extractor, the paste being heat-cured after the completion of assembly. Others involve a fine wire or spring strip from one filament post to the walls of the extractor cup. Other schemes include welded or brazed wires or foil, crimping, pinching, swaging and other connections, all made inside the tube enclosure.

Abstract: Age-related macular degeneration is treated by radiation delivered from a miniature x-ray tube inserted via a catheter around the globe of the eye, to a position behind the macula. The process can employ an applicator with several parallel guides, inserted around the eye to receive the catheter with x-ray tube (or an isotope) at a matrix of different positions. Methods are described for properly locating the catheter and x-ray tube, using illumination on the catheter and viewing through the front of the eye, or sensors on the catheter and a scanned beam shone from the front of the eye. Fluorescent material excited by x-rays can also be used. Also described are methods and devices for immobilizing the probe once properly located in the eye, for standoff of the x-ray tube from the target tissue, and for achieving prescription radiation dose in the choroid while eliminating dose to adjacent tissues. The x-ray treatment can be enhanced using a radiosensitizing drug, and can be combined with PDT.

Abstract: A medical pill intended for human or animal consumption includes an RF ID tag in or on the pill. The tag will respond to a nearby reader, the tag itself being without a battery or other constant power supply, capturing power from the reader's transmitted signal and storing a portion of that power in a power supply. An antenna for the RF ID tag may be integral with the tag or it may be transferred to the pill using conductive materials in the pill's coating, filler or binding agents, embedded within the pill, or printed onto the pill. If separate from the tag the antenna is electromagnetically coupled to the tag which has a small onboard antenna. The RF ID tag of each pill has data that are transmitted when the tag is interrogated by a signal from a reader. Incorporation of an ingestable ID tag is possible because of the tag's very small size compatible with ingestion and because the tag can contain an antenna within the pill that allows the tag to be read at a substantial distance.

Abstract: An electronic identification tag, usually in very small size, responds to a reader with an identification code unique to the object to which the tag is attached. The stand-alone device responds to a reader signal by storing energy received from the signal, then using the stored energy to generate another signal that is encoded with identification information. In operation, a reader generates RF energy which can reach a multiplicity of such tags over a distance of several meters. The system minimizes power requirements for the tag by minimizing intelligence in the IC. Use of a transmit frequency which is different from the reader's power frequency reduces interference between the power pulse and information pulse, eliminates the need for filters and enables the multiplied clock reference frequency as the transmit carrier frequency.

Abstract: In a miniature x-ray tube, which may be on the order of approximately 1 mm in diameter or even less, a high voltage cable is provided in various embodiments for conducting current to the cathode of the x-ray tube and for conducting high voltage to the cathode and anode of the tube. In various embodiments of the cable, two conductors occupy a center region of the cable, packed as closely together as possible, in various shapes that are compact and present as smooth as possible an external shape for maximizing dielectric properties against the exterior high voltage ground, surrounding and generally concentric with the inner conductors. The inner conductors, which carry high voltage in opposition to the outer ground, can be in opposed D shapes, coaxial, two flattened conductors side by side, or simply a pair of cylindrical wires positioned as closely as possible.

Abstract: A miniature x-ray tube capable of intra vascular use, has a micro cathode preferably formed by MEMS techniques. The very fine wire of the cathode filament is formed on a semiconductor base and draws a current sufficiently low that lead wires in a cathode heater circuit, passing through a probe line connected to the x-ray tube, can be very small wires, which helps maintain sufficient dielectric spacing in the high voltage circuit handled by the same probe line. In a preferred embodiment the probe line comprises a glass fiber, held at a small diameter to allow flexibility for navigating small-radius turns within the vessels. In a preferred embodiment the fiber is overcoated with a high-dielectric polymer to significantly increase the dielectric strength of the overall cable, without adding significantly to stiffness. The high voltage ground conductor is a coaxial sheath on the outside of the polymer. Exterior to the ground conductor is a further flexible layer having paths for coolant.

Abstract: Methods and apparatus are described for irradiating living tissue via a cavity or lumen, using an inflatable balloon applicator. In a preferred embodiment the applicator balloon has a balloon skin with x-ray contrast material in relatively low concentration, so that an outline of the balloon will appear sharply when imaged externally. In another preferred embodiment the balloon catheter has a drain for withdrawing liquids from the cavity, which may include channels or texture on the exterior of the balloon. Methods are described for using a switchable miniature x-ray tube, variable as to voltage and current, to achieve accuracy in an isodose profile.

Abstract: An applicator for facilitating radiation treatment in a body cavity, particularly post resection, provides for superior wound closure management, with an integrated drain and a flexible main shaft that permits further treatments at intervals without disturbing the wound closure. The drain includes channels in the shaft, and the surface of an expandable balloon of the applicator may have features that help channel the flow of drain liquids toward the cavity entrance. Non-spherical, irregular geometries of balloons are achieved in several different ways. In some embodiments multiple balloons are included, either an inner and outer balloon or a series of balloons extending outwardly from the main shaft. Non-balloon applicators are also disclosed.

Abstract: In a miniature x-ray tube, which may be on the order of approximately 1 mm in diameter or even less, a high voltage cable is provided in various embodiments for conducting current to the cathode of the x-ray tube and for conducting high voltage to the cathode and anode of the tube. In various embodiments of the cable, two conductors occupy a center region of the cable, packed as closely together as possible, in various shapes that are compact and present as smooth as possible an external shape for maximizing dielectric properties against the exterior high voltage ground, surrounding and generally concentric with the inner conductors. The inner conductors, which carry high voltage in opposition to the outer ground, can be in opposed D shapes, coaxial, two flattened conductors side by side, or simply a pair of cylindrical wires positioned as closely as possible.