Abstract: Point-of-sale display apparatus for a plurality of flag designs comprises a generally flat back panel having a bottom edge portion and an upper edge portion. A flag retaining means is fastened to the back panel and defines a plurality of loops sized to accommodate a rolled flag in each of the loops. The loops are preferably comprised of elastic material. The upper edge portion may be generally triangular shaped with the apex of the triangle defining a point from which the display apparatus can be hung. The display apparatus also includes a clear, plastic enclosure shaped to accommodate the display apparatus within the enclosure. The display apparatus is used to display for sale a plurality of flag unfurlers and a variety of flag designs, and doubles as a convenient and effective storage container.

Abstract: An RF coil structure for intra-cavity use includes a pair of conductors (7, 8) separated by a support such as a web (9) which come together at positions separated along the length of the coil structure such as (A, B). Previous coils have included two parallel conductors. If the conductors (7) and (8) were parallel, while the structure could be flexed transverse to the plane of the web (9) about the arrow (10), it could not be flexed in the plane of the web (9) about arrows (12, 13). Because the conductors come together at points (A) and (B), it can be so flexed. A second coil may be provided including conductors (4, 5) and flexing about the same points as for the first coil is still possible because the points of closest approach for one pair come between those for the other pair.

Abstract: When imaging a region of a patient using a contrast agent, for example in magnetic resonance imaging apparatus including a superconducting magnet 2, it is usual to take an image before and after injection of a contrast agent from an injector 5 into the patient. The invention provides a second injector 8 which contains a sample of the patient's blood or saline or other injectable medium which leads directly to the region of interest being imaged in the patient via a catheter 9, which has an expandible tip which can be expanded to block off the vessel in question. The injector can then be used to inject a bolus of injectable medium into the region of interest, whereupon a further image can be taken, and the catheter can be collapsed to unblock the vein whereupon an image in the presence of the contrast agent can be taken.

Abstract: An r.f. coil arrangement for use in a magnetic resonance imaging apparatus includes conductors etched on either side of a circuit board. Corresponding portions of conductors locating on opposite sides of the circuit board overlap so as to form a plurality of capacitors which provide electrical connection for current flowing in the coil. The conductors on the first side of the circuit board form a spiral in which the current flows from the outside of the spiral to the inside. The conductors on the second side form a spiral in which the current flows from the inside of the spiral to the outside. Auxiliary conductor portions may be readily disconnected from the main conductors so that the value of the capacitors may be adjusted.

Abstract: A patient bed (1) of an MR imaging apparatus is provided with a tube (17) through which pre-polarised fluid can be injected into a patient in order to improve contrast when imaging veins, arteries or other vessels in the body. Fluid is delivered from pump (2) into a high field polarising magnet (3) and along a tube (4) to the patient. Valve (5) is provided so that fluid in the tube (4) downstream of the pre-polarised fluid can be discarded rather than being injected in the patient, and is associated with a reservoir into which the fluid to be discarded and the pre-polarised fluid can be rapidly injected. Then, when the pre-polarised fluid is injected into the patient, its magnetisation has not deteriorated by as much as it would have done if the tube (4) had been directly connected into the patient.

Abstract: A transmission radiation source assembly suitable for use in both SPECT and PET imaging includes a line source assembly having a medium energy transmission source. The line source assembly includes a primary collimator rotatably disposed about the medium energy transmission source. The primary collimator includes one or more beam limiting slots for shaping the width of a transmission beam emitted from the line source. An on/off collimator is rotatably disposed about the primary collimator and serves to control the on/off state of the line source. The on/off collimator includes a beam exit slot which, when aligned with one of the beam limiting slots allows the transmission beam to exit the line source. In order to sweep the transmission beam across an opposing detector head, the primary collimator and on/off collimator are synchronously rotated about an axis of rotation of the line source with the on/off collimator in the “on” position.

Abstract: An evacuated tube (24) includes an envelope (50) and an electrode (78) in the tube envelope (50). The electrode (78) is electrically connected to conductors (74a, 74b) that extend through the tube envelope (50). A getter (72) is included in the tube envelope (50) and is electrically connected to the conductors (74a, 74b) extending through the tube envelope (50). Diodes (82a, 82b) are connected to the electrode (78) and the getter (72) for selectively providing electrical energy through the conductors (74a, 74b) extending through the tube envelope (50) to one of the electrode (78) and the getter (72).

Abstract: A gamma camera system includes a rotatable gantry supporting multiple detector heads each capable of receiving radiation from a region of interest of a subject disposed in an examination region. Each of the detector heads include a collimator which substantially defines the resolution and sensitivity of the respective detector head. At least two of the detector heads include collimators providing different resolution. Preferably, one of the collimators provides a detector head with substantially high resolution and another provides a detector head with substantially high sensitivity. An operator selectively combines image data detected by each of the multiple detector heads. If desired, the operator combine the image data from the multiple detector heads in a variety of manners to obtain images of various resolution and sensitivity from a single imaging procedure. The operator may also selectively weight the contribution that the image data from each of the detector heads has in the overall image.

Abstract: A gamma camera includes detector heads disposed about an examination region. A high energy collimator collimates the radiation received by each of the detector heads. Either a positron emitting radionuclide or a positron emitting radionuclide and a single photon emitting radionuclide is introduced into an object to be imaged. Radiation which is received by the detectors within a coincidence time interval and radiation which is received by either of the detectors but having an energy characteristic of a positron annihilation are used to generate coincidence data. Radiation which is not indicative of coincidence radiation but which has an energy characteristic of the single photon emitting radionuclide is used to generate single photon data. The data is processed and used to generate one or more images of the object.

Abstract: A diagnostic imaging system includes oppositely disposed radiation detectors (32, 34) configured to detect coincidence radiation events caused by a substance injected into a subject which generates positron emissions. A coincidence data processor (40) collects and processes the radiation detected by the detectors (32, 34) and a coincidence circuitry (44) matches and compares the detected events to determine coincidence. Coincidence data is generated and stored in a coincidence data memory (46). A collimated radiation detector (50) is disposed at an angle to the coincidence radiation detectors (32, 34) and is configured to detect single photon radiation traveling along a selected projection path determined by a collimator (52) mounted on a front face of the collimated radiation detector (50). A single photon data processor (60) generates collimated data (74) based on the radiation detected by the collimated radiation detector (50).

Abstract: A gamma camera includes first and second detectors which face an examination region. The detectors are rotatable about the examination region and translatable in a direction tangential to the examination region. Translation of the detectors is coordinated with the rotation of the detectors about the examination so as to increase the effective field of view of the detectors. In a first embodiment, the detectors are translated in the transverse direction when the detectors are located at each of a plurality of positions about the examination region. In a second embodiment, translation of the detectors is coordinated such that, for a given projection angle, the first detector is used to detect radiation data from a subset of the region of interest.

Abstract: Shielded gradient coils are adapted for use in an MR imaging apparatus having spaced apart pole pieces. The x, y, and z coils each include a active and shield layers. The x-active and shield layers are interconnected by a plurality of vertical electrical connections extending around the periphery of the coil. The y-active and shield layers are similarly connected. The z-active and shield layers each have a generally spiral conductor pattern.

Abstract: The configuration of a multi-head gamma camera requires coordination between tangential and radial motions so that the detectors maintain a desired orientation, either corner to corner or overlapping. Based on the radial and angular positions of the detectors, desired tangential positions are determined. The desired tangential positions are compared with the actual tangential positions, to generate position error signals. Tangential motion is initiated to reduce the position errors. If the required tangential motion exceeds the capability of the tangential drive or cannot be achieved, the radial motion is slowed or stopped.

Abstract: An x-ray tube includes an envelope defining an evacuated chamber in which an anode assembly is rotatably mounted to a bearing assembly and interacts with a cathode assembly for production of x-rays. The x-ray tube further includes a heat shield disposed in the envelope. The heat shield serves to reduce heat radiating from the anode assembly which is transferred to the bearing assembly or otherwise serves to insulate the bearing assembly from such radiated heat. The heat shield is brazed or otherwise bonded to the anode assembly and is comprised of a material having a low emissivity so that a minimum amount of heat radiates through the heat shield.

Abstract: A transformable gamma camera includes detectors mounted for circumferential movement with respect to a rotating gantry. The rotating gantry includes radial bores at desired angular positions about the rotating gantry. The stationary gantry includes a docking station such as a bore. A coupling mechanism allows the detectors to be coupled to the bores in the rotating gantry or to the docking station. Each of the detectors is movable radially with respect to the rotating gantry's axis of rotation and tangentially to the imaging region. The gamma camera is readily transformable between 120 degree, orthogonal, and opposed detector configurations; a plurality of aperture sizes can also be defined.

Abstract: A gamma camera includes at least one detector assembly 10. The detector assembly includes an array of photomultiplier tubes, a sheet of scintillating crystal material, a sheet of optical glass, and a matrix of mu-metal material. The mu-metal matrix defines an array of apertures corresponding to the array of photomultiplier tubes into which apertures the photomultiplier tubes are inserted. The scintillating crystal is bonded to the first surface of the optical glass. The mu-metal matrix is connected to the second surface of the sheet of optical glass using an adhesive such as an epoxy cement. By integrating the metal matrix into the structure formed by the glass sheet and the crystal, the glass sheet may be made thinner than before while the crystal is supported against possible bending and consequent fracture.

Abstract: A magnet having a yoke and a pair of poles coupled to the yoke in a spaced apart relationship includes a pair of energization coils in proximity to each of the poles for creating a magnetic field of a desired strength. A pair of prepolarization coils are also disposed in proximity to each of the poles to vary the strength of the magnetic field during a nuclear magnetic resonance prepolarization procedure. In order to minimize the amount of eddy currents introduced to the yoke during the prepolarization procedure the poles are comprised of magnetically effective and substantially non-electrically conductive material. Magnetically effective material includes material having a low hystresis. To further reduce the amount of eddy currents introduced to yoke, a flux is created having a sense substantially opposite of that produced by the energization coil. Such opposing flux may be produced by the prepolarization coils and/or by a shield winding placed in proximity of the poles for that purpose.

Abstract: An object (22) is positioned on a patient support (25) between an x-ray source (10) and an x-ray detector assembly (15). The x-ray source (10) is selectively activated to transmit an x-ray beam (20) through an imaging region (32) to the x-ray detector assembly (15). Positioning of the object (22) on the patient support (25) is such that a gap 33 exists in the imaging region (32) through which x-rays may pass unattenuated. An x-ray equalization filter (30) is introduced into the gap 33 and substantially conforms to its shape. The equalization filter (30) comprises a fluid medium disposed in a flexible receptacle. The fluid medium contains x-ray attenuating material suspended in a gel base. Placement of the equalization filter (30) in the gap reduces the number of unattenuated x-rays reaching the x-ray detector assembly (15) thereby enhancing image quality.

Abstract: A microscope calibrator includes a housing supporting a series of focusing targets each situated at a predetermined distance from one another. Attributes of the microscope are determined by focusing the microscope on one ore more of the focusing targetrs and determining a location of the microscope with respect to the focusing targets focused upon. The position of the focusing targets are determinable by virtue of a local reference frame target attached to the microscope calibrator or by using a tracked probe to communicate the location of each point focused upon by the microscope on each of the focusing targets.

Abstract: An apparatus (1) for supporting a surgical instrument in the operative environment of an imaging device comprises components all made of a material compatible for use in the operative environment of the imaging device. The components of the apparatus (1), made of such a material, include a member (32) that has a spherical surface and includes a bore (50) extending through the member along its diameter. A grip (26) has a grip surface (40) defining an aperture that is adapted to receive the member for rotatable movement within the aperture. The grip (26) extends around the member (32) in a circumferential path and has a gap (42) therein. A fastener (30) is operatively connected to the grip (26). The fastener (30) is adjustable to change the size of the gap (42) and adjust the compressive force applied to the received member (32) in the grip.