Abstract: Surgical implements used during an operating procedure are detected in human tissue. Markers attached to the surgical implements change their impedance at a preselected frequency in the presence of an electromagnetic field. Each of the markers is thereby provided with signal-identifying characteristics. The signal-identifying characteristics are detected outside the operating room in an accurate, reliable manner. Potential interference with operating room electronic instrumentation is avoided, the possibility of operator error is reduced and system cost and space requirements are substantially lowered.

Abstract: Surgical implements used during an operating procedure are detected in human or animal tissue. Markers attached to the surgical implements change their impedance at a preselected frequency in the presence of an electromagnetic field. Each of the markers is thereby provided with signal-identifying characteristics. The signal-identifying characteristics are detected by a freely movable, portable detection unit from a first location proximate the patient in an accurate, reliable manner. Potential cross-interference with operating room electronic instrumentation is minimized by shielding. System cost and space requirements are substantially lowered. An accidentally retained surgical implement is discovered in a timely manner, prior to completion of surgery and before the patient has been removed from the operating room.

Abstract: Externally detectable electronic article surveillance markers are attached to surgical implements, such as sponges and surgical instruments, appointed for use in a surgical wound. The attachment mechanism facilitates detection by an external interrogating field before the wound has been closed and the patient has left the operating table. The markers are responsive to the imposition of an interrogating field produced by an electronic article surveillance system. Markers contain one or more magnetomechanically responsive elements that are urged into mechanical resonance by the interrogating field. The ring-down of the resonance and the associated dipolar electromagnetic field provide a signal-identifying characteristic detected by a detection system. Upon detection, an audible or visible signal is triggered to alert relevant medical personnel to the need for follow-up care and removal of the offending item. The resonance occurs at a frequency ranging from about 70 to 300 kHz.

Abstract: A surgical sponge comprises a plurality of radiopaque markers having a high radiographic density and a distinctive, visually recognizable shape. The markers have an x-ray density equivalent to at least about 0.1 g/cm2 of BaSO4. The markers produce an x-ray image with high contrast and a shape that is readily recognizable and differentiated from the images produced by other items and structures commonly seen in x-rays of post-operative patients. Owing to the distinctive, high contrast image produced by the markers, the sponge is reliably and unambiguously detected. This is so even in situations where the sponge is inadvertently left in the surgical wound. Discomfort, trauma, and possibly fatal consequences that might otherwise occur are virtually eliminated. The surgical procedure is carried out with decreased likelihood of a sponge being retained inadvertently.

Abstract: Provided is a detector system for detecting a plurality of items each having at least one RFID tag attached thereto. The detector system may include a presence detector and/or a message detector. The presence detector may include a signal reader which receives modulated carrier frequencies from the RFID tags during a predetermined response time period for comparison to a reference level. The signal reader may be configured as a power integrator or a constellation discriminator. The power integrator sums the power contained in signals transmitted by the RFID tags by integration for comparison to an environmental noise level measurement taken during a quiet period. For the constellation discriminator, bits contained in the modulating message are compared to the bit pattern of a predetermined reference constellation. The detector system may be configured as a 3-state detector which combines the presence detector with a message detector that indicates the identification code of the RFID tags.

Abstract: Externally detectable electronic article surveillance markers are attached to surgical implements, such as sponges and surgical instruments, appointed for use in a surgical wound. The attachment mechanism facilitates detection by an external interrogating field before the wound has been closed and the patient has left the operating table. The markers are responsive to the imposition of an interrogating field produced by an electronic article surveillance system. Use of the attachment mechanism and markers assure that the surgical implements are reliably detected and removed before completion of the surgical procedure. This technique eliminates the not infrequent mishap in which an implement is undiscovered at the time of surgery and remains indefinitely within the surgical cavity, often entailing dire consequences to the patient.

Abstract: A radio-frequency surgical implement detection system detects surgical implements in a surgical wound during and at the completion of a surgical procedure. Surgical implements, including surgical sponges or laparotomy pads, gauze pads and metallic surgical instruments, are individually attached to a non battery-powered, encapsulated radio-frequency marker. The marker comprises an integrated chip having a burnt-in memory code, which is broadcast through an antenna using a modulated carrier frequency. The code is received by an interrogating antenna of a detector. The interrogating antenna provides a power pulse, which is received by the antenna of the radio-frequency marker. The power pulse charges a capacitor, which proves power for the read function, carrier frequency modulation function and broadcast function of the integrated chip, permitting each marker-containing implement to be specifically identified.

Abstract: A miniature magnetic article surveillance system marker is adapted, when armed, to resonate at a frequency provided by an incident magnetic field applied within an interrogation zone. The marker comprises a magnetomechanical element having at least one elongated ductile strip of magnetostrictive ferromagnetic material disposed adjacent to a ferromagnetic element which, upon being magnetized, magnetically biases the strip and arms it to resonate at said frequency. A substantial change in effective magnetic permeability of the marker at the resonant frequency provides the marker with signal identity.

Abstract: An accurate, fast-acting, wearable lightning strike hazard detector has a plurality of collecting plates for collection of arriving charged particles. The collecting plates are insulated from each other by an insulating mechanism. A connecting mechanism electrically connects the collecting plates to a bleeding circuit to bleed accumulated charges to a ground plane. The voltage within the bleeding circuit is determined by a voltage measuring mechanism. A voltage accumulation mechanism measures the accumulated voltage of each plate and its rate of voltage accumulation as a function of time. Voltage accumulation and voltage/time data are interpreted by an algorithm to determine lightning strike potential. A signal generating mechanism connected to the algorithm mechanism generates a signal when said voltage accumulation and voltage accumulation rate exceed preselected limits. The signal actuates an alarm mechanism, which provides an audible or visual alarm to warn against an impending lightning strike.

Abstract: A miniature magnetic article surveillance system marker is adapted, when armed, to resonate at a frequency provided by an incident magnetic field applied within an interrogation zone. The marker comprises a magnetomechanical element having at least one elongated ductile strip of magnetostrictive ferromagnetic material disposed adjacent to a ferromagnetic element which, upon being magnetized, magnetically biases the strip and arms it to resonate at said frequency. A substantial change in effective magnetic permeability of the marker at the resonant frequency provides the marker with signal identity.

Abstract: Externally detectable electronic article surveillance markers are attached to surgical implements, such as sponges and surgical instruments, appointed for use in a surgical wound. The attachment mechanism facilitates detection by an external interrogating field before the wound has been closed and the patient has left the operating table. The markers are responsive to the imposition of an interrogating field produced by an electronic article surveillance system. Markers contain one or more magnetomechanically responsive elements that are urged into mechanical resonance by the interrogating field. The ring-down of the resonance and the associated dipolar electromagnetic field provide a signal-identifying characteristic detected by a detection system. Upon detection, an audible or visible signal is triggered to alert relevant medical personnel to the need for follow-up care and removal of the offending item. The resonance occurs at a frequency ranging from about 70 to 300 kHz.

Abstract: Surgical implements used during an operating procedure are detected in human tissue. Markers attached to the surgical implements change their impedance at a preselected frequency in the presence of an electromagnetic field. Each of the markers is thereby provided with signal-identifying characteristics. The signal-identifying characteristics are detected outside the operating room in an accurate, reliable manner. Potential interference with operating room electronic instrumentation is avoided, the possibility of operator error is reduced and system cost and space requirements are substantially lowered.

Abstract: Diseased tissue is liquefied in the presence of non-diseased tissue by contact with a paddle moving with angular velocity. The edge of the paddle is dull and the angular velocity is sufficient to batter the diseased tissue into a liquid without adversely affecting the structure and function of the non-diseased tissue. The shape of the paddle and the rotational speed can be designed and chosen depending on the consistency of the tissue to be resected, whether hard or soft. Upon liquefaction, the diseased tissue is removed by vacuum aspiration. This instrument therefore gives the neurosurgeon the ability to differentially resect diseased tissue while preserving the surrounding structures intact.

Abstract: The present invention provides a method and apparatus for accurately and reliably detecting surgical implements within animal or human tissue. The apparatus comprises a detector responsive to the presence, within a wound, of a surgical implement to which a marker is secured. The marker is adapted to produce identifying acoustic signal characteristics within the wound.

Abstract: The present invention provides an X ray film cassette with a permanent marking means for identifying the side of the radiographic film that faced the X ray tube during exposure. Such identification does not require any action by the X ray technologist, eliminating the element of human error. The marking means is comprised of chirally asymmetric X ray opaque and/or light-opaque letters or markings permanently mounted in the film cassette to intersect overlapping portions of an X ray path projected during exposure.

Abstract: An X ray film cassette has a marking mechanism whereby unique identification of the film cassette is provided by film exposed therewithin. Plural light-opaque markers mounted in the film cassette provide means for marking the X ray film therein during exposure with an image correlated with a marking on the cassette exterior, thereby indicating the particular cassette within which the X ray film was exposed.

Abstract: A radiographic film packet is adapted to be placed in a patient's mouth for exposing a sheet of dental film to x-rays generated by an x-ray tube. The packet comprises: a light-proof envelope having a first side and second side defining a pocket for receiving the film sheet; a sheet of lead disposed within the pocket adjacent the second side; a sheet of film disposed within the pocket between the lead sheet and the first side; an indicator affixed to the first side of the envelope, the indicator expressly designated the edge of the film packet appointed to be uppermost in the mouth during radiographic exposure; and a marker comprising a perforation in the periphery of the film sheet.

Abstract: A chirally asymmetric marking on a sheet of radiographic film, positively identifies the side of the film sheet facing the front of an x-ray cassette during radiographic exposure. The marking is permanent and is accomplished automatically in an inexpensive, convenient and highly reliable manner.

Abstract: An apparatus for detecting a surgical implement in human or animal tissue has structure for defining a transmitting zone encompassing a surgical wound in the tissue. A battery powered marker is secured to a surgical implement positioned within the wound. Field generating structure is provided for generating within the transmitting zone an electromagnetic field having a predetermined frequency band. A signal generator generates a signal having a predetermined frequency band. The signal generator is operative to cause the field generating structure to generate the electromagnetic field, providing the marker with signal identity. A detector having an antenna located within the transmitting zone of the marker detects the marker signal irrespective of the marker's orientation therewithin.

Abstract: The present invention provides an X ray film cassette with a permanent marking means for identifying the side of the radiographic film that faced the X ray tube during exposure. Such identification is achieved irrespective of whether the film is exposed through the cover or base of the cassette and does not require any separate action by the X ray technologist, eliminating the element of human error. In a preferred embodiment, the working means is comprised of chirally asymmetric X ray opaque and/or light-opaque letters or markings permanently mounted in the film cassette. A user friendly apparatus is described, for installing the light-opaque markers on the intensifying screens of the X ray film cassette.