Abstract: A method to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter the high-field region of an MRI suite. The device used comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The method places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: A hand held apparatus and method for detecting paper currency, within a package, where the paper currency has a ferromagnetic component. The apparatus includes a DC magnetic field source for inducing a DC de-magnetization field in any ferromagnetic paper currency that may be present within a package, and DC magnetic sensors for detecting certain characteristic patterns in the DC “de-mag” field induced by the DC magnetic field source. These certain characteristic field patterns are indicative of paper currency arranged in commonly found arrangements.

Abstract: An object detection portal wherein a video image is obtained of a volume or area being scanned, and location of a threat object is determined and displayed in real time as an indicator overlay on the video image. An individual subject being scanned may be continuously monitored by an operator during an object divesting process, and an operator may view the threat object moving from or remaining with the subject. Object location information is supplied to a video driver to superimpose the overlay on a real time image of a subject. The scanning portal may interact with an exit barrier. The exit barrier may be activated automatically in response to sensing of a threat.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter the high-field region of an MRI suite. The device comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a controlled area. The device comprises a screening portal, including multiple sensor arrays and associated electronics. The device places the sensor arrays in close proximity to a subject's body, including the head and feet if desired, for screening purposes. The portal can have multiple excitation sources oriented to generate a multi-axis excitation field, and multi-axis sensors. The portal can also have an interlock with the door of the controlled area.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a security area. The device comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: A probe instrument using room-temperature sensor(s) that can measure variations in magnetic susceptibilities. The instrument has sufficient resolution to monitor paramagnetic materials in a human body, such as iron in a human liver, by noninvasively examining patients with iron-overload diseases. The instrument includes room temperature magnetic sensors, and detects the sample, that is, the tissue response to an alternating current field applied by an applied field coil. The applied field coil dimensions are chosen so that the applied field is optimized for maximum response from the liver while minimizing the effects due to the overlying abdominal tissue and at the same time not unduly increasing the sensitivity of the instrument to the lung. To overcome variations in the sensor output due to fluctuations in the applied field, change in the ambient temperature and mechanical relaxation of the instrument, the sensor-sample distance is modulated.

Abstract: Methods and apparatus for minimizing the effects of temperature drift in a magnetic susceptibility measurement instrument, such as an instrument used in pre-MRI screening for the presence of ferromagnetic foreign bodies. The magnetic field source and magnetic sensors can be combined into a single, rigid unit. The stability and sensitivity required in high quality magnetic susceptibility measurements can be achieved through symmetrical design of the source-sensor unit, minimization of thermal stresses, minimization of temperature variations, use of materials with low thermal expansion coefficients, or through appropriate combinations thereof. Use of patient eye movement where an eye is being screened, use of a water bag between the patient and the instrument, or use of telemedicine to facilitate performance of the necessary computations can also be incorporated.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a controlled area. The device comprises a screening portal, including at least one magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to a subject's body, for screening purposes. The portal has at least one excitation coil oriented to cause the excitation field to have zero mutual inductance with the gradiometers.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a controlled area. The device comprises a screening portal, including multiple sensor arrays and associated electronics. The device places the sensor arrays in close proximity to a subject's body, including the head and feet if desired, for screening purposes. The portal can have multiple excitation sources oriented to generate a multi-axis excitation field, and multi-axis sensors. The portal can also have an interlock with the door of the controlled area.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a controlled area. The device comprises a screening portal, including at least one magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to a subject's body, for screening purposes. The portal has at least one excitation coil oriented to cause the excitation field to have zero mutual inductance with the gradiometers.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter the high-field region of an MRI suite. The device comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a security area. The device comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: An object detection portal wherein a video image is obtained of a volume or area being scanned, and location of a threat object is determined and displayed in real time as an indicator overlay on the video image. An individual subject being scanned may be continuously monitored by an operator during an object divesting process, and an operator may view the threat object moving from or remaining with the subject. Object location information is supplied to a video driver to superimpose the overlay on a real time image of a subject. The scanning portal may interact with an exit barrier. The exit barrier may be activated automatically in response to sensing of a threat.

Abstract: Methods are disclosed for non-invasive screening of the human body by rejecting the magnetic response from biological tissues in the region of interest and outputting data corresponding to the magnetic response of a ferromagnetic foreign body within the region of interest.

Abstract: Methods and apparatus for minimizing the effects of temperature drift in a magnetic susceptibility measurement instrument, such as an instrument used in pre-MRI screening for the presence of ferromagnetic foreign bodies. The magnetic field source and magnetic sensors can be combined into a single, rigid unit. The stability and sensitivity required in high quality magnetic susceptibility measurements can be achieved through symmetrical design of the source-sensor unit, minimization of thermal stresses, minimization of temperature variations, use of materials with low thermal expansion coefficients, or through appropriate combinations thereof. Use of patient eye movement where an eye is being screened, use of a water bag between the patient and the instrument, or use of telemedicine to facilitate performance of the necessary computations can also be incorporated.

Abstract: A probe instrument using room-temperature sensor(s) that can measure magnetic susceptibilities variations. The instrument includes room temperature magnetic sensors, and detects the sample, that is the tissue response to an applied field coil. The sensors that can be used include magnetoresistive, fluxgate and magnetoinductive sensors. The applied field coil dimensions are chosen so that the applied field is optimized for maximum response from the item of interest while minimizing the effects due to the overlying tissue and at the same time not unduly increasing the sensitivity of the instrument to adjacent organs. To minimize noise introduced in the sensor due to fluctuations in the applied field, the applied field is canceled at the position of the sensor. To overcome variations in the sensor output due to fluctuations in the applied field, change in the ambient temperature and mechanical relaxation of the instrument, the detector assembly is oscillated while the examined patient remains stationary.

Abstract: A method for rejecting the magnetic response of surrounding biological tissues, in measuring the magnetic susceptibility response of a region of interest in a patient, to detect the presence of ferromagnetic foreign bodies. The magnetic response of the surrounding tissues is rejected by defining a statistically determined normal range of magnetic susceptibility responses, or by rejecting magnetic field responses characteristic of materials with isotropic magnetization properties.

Abstract: A probe instrument using room-temperature sensor(s) that can measure variations in magnetic susceptibilities. The instrument has sufficient resolution to monitor paramagnetic materials in a human body, such as iron in a human liver, by noninvasively examining patients with iron-overload diseases. The instrument includes room temperature magnetic sensors, and detects the sample, that is, the tissue response to an alternating current field applied by an applied field coil. The applied field coil dimensions are chosen so that the applied field is optimized for maximum response from the liver while minimizing the effects due to the overlying abdominal tissue and at the same time not unduly increasing the sensitivity of the instrument to the lung. To overcome variations in the sensor output due to fluctuations in the applied field, change in the ambient temperature and mechanical relaxation of the instrument, the sensor-sample distance is modulated.

Abstract: A probe instrument using room-temperature sensor(s) that can measure magnetic susceptibilities variations. The instrument includes room temperature magnetic sensors, and detects the sample, that is the tissue response to an applied field coil. The sensors that can be used include magnetoresistive, fluxgate and magnetoinductive sensors. The applied field coil dimensions are chosen so that the applied field is optimized for maximum response from the item of interest while minimizing the effects due to the overlying tissue and at the same time not unduly increasing the sensitivity of the instrument to adjacent organs. To minimize noise introduced in the sensor due to fluctuations in the applied field, the applied field is canceled at the position of the sensor. To overcome variations in the sensor output due to fluctuations in the applied field, change in the ambient temperature and mechanical relaxation of the instrument, the detector assembly is oscillated while the examined patient remains stationary.