Abstract: A blackline indictor for use in tomographic and/or radioscopic inspection of a weld joint is disclosed. The indicator includes a first elongated member having a first end and a second end and a second elongated member juxtaposed to said first member and also having a first end and a second end. The first ends of the elongated members are in contact with one another, and a spacer is disposed between the first and second members to position the second ends of the members at a selected distance from one another. The selected distance is at least equal to a thickness of the weld joint under inspection, and the first and second members and the spacer define a calibrated wedge shaped gap which is radiographically imageable to permit determination and control of the x-ray inspection parameters.

Abstract: A mechanism/device (29) in association with a radiographic cassette (20) in which X-ray film (28) or the like is exposed. Upon exposure, an LED (39) continually blinks, indicating exposure to the user, thereby obviating double exposure of the film. A test and reset circuit (80) informs the user at any time of the operational status of device (29). Device (29) comprises a sensor (30), a photodiode (47), a conduit formed by a bundle (31) of optical fibers which conveys light energy from sensor (30) to photodiode (47) that converts it into an electrical current controlled by an electronic circuit (35) which includes LED (39). Circuit (35) includes a detecting and amplifying circuit (51), an oscillating circuit (68), a latching circuit (65) for maintaining blinking of LED (39), and the test-and-reset circuit (80).

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 lithotripsy workstation, comprises a patient supporting device (1), a shockwave source (4) for generating shockwaves which are focused onto a point (focus) (6) fixed in space, an X-ray source (10) which irradiates the focus (6) from at least two defined positions, and an image detector (12) which detects the X-ray image produced by the X-ray source (10). The cost and the weight of the workstation can be reduced in that a marker (16) which can be displayed in the X-ray image is secured to the X-ray source (10), which marker is situated, at least in the two positions, on the connecting line between the focal spot (11) of the X-ray source (10) and the focus (6).

Abstract: An angle indicating device is provided for measuring the angle of an X-ray machine and to display the angle on the photographic plate at the time it is exposed to X-rays. The invention includes the combination of a pendulum mounted to maintain a vertical orientation during rotation of the X-ray machine about its horizontal axis, and an indicator for indicating the angle of the X-ray machine relative to a vertical orientation of the pendulum. Furthermore, a scale and a scale indicator, both of which are opaque to X-rays is provided to project the read out of the angle indicator upon the photographic plate.

Abstract: A penetrameter is provided for use in evaluating the resolution of an x-ray inspection system as well a method for calibrating the resolution of the x-ray inspection system. The penetrameter comprises a radiolucent substrate, and at least one filament at the radiolucent substrate, the at least one filament being broken by a gap having a predetermined size. The method of determining the resolution of an x-ray inspection system comprises steps of: generating a radiographic image of the penetrameter, determining if the broken filament is visible, and if the broken filament is visible, determining if the gap is visible.

Abstract: A radiograph identification and filing apparatus and method for photographically imprinting information onto radiographic film and filing the radiographic film. The apparatus comprises an adhesive-backed label and a jacket for storing the film. When used with a darkroom radiograph imprinter, the label, the adhesive backing for the label, and the release liner are all photo-transparent. When used with a radiograph ID camera, the label is photo-opaque. The label is divided into a plurality of information fields which include print information material. In a label for use with an imprinter, the print information is photo-opaque. The jacket includes a pocket for receiving the film and exterior surfaces for receiving the label. For an imprinter, the method includes providing a label having an imprint field having substantially the same dimensions as the light window of the imprinter.

Abstract: A device for assisting a fluoroscope operator in orienting a fluoroscope on an object during a fluoroscope examination, and thereby reduce the time of use and exposure to radiation, which device consists of a sheet transparent to x-ray radiation, preferably disc shaped, possessing orientation indication means, such as radiopaque symbols, numbers and letters which may be combined in any combination. The orientation device is mounted on the fluoroscope's receiver, thereby positioning the sheet and orientation indicators between the receiver tube and the object being examined. The orientation indicators are visible on the fluoroscope's monitor, clearly indicating direction and providing guidance for the fluoroscope operator during the examination.

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.

Abstract: A method and apparatus for storing and displaying radiographs, particularly intra-oral radiographs, is presented. Radiographs are captured, digitized, and displayed along with an icon of a portion of the anatomy from which the radiograph was taken. The anatomical sites represented by the icon are arranged according to their normal anatomical relationship. The icon is used by the system user to select a portion of the anatomy corresponding to the displayed radiograph, and the radiograph is stored along with indicia of the selected anatomical site. Then, when the stored radiograph is desired to be viewed, the icon is again displayed, and the appropriate anatomical site is selected, which causes the corresponding radiograph to be retrieved from storage and displayed.

Abstract: A multidiagnostic rectilinear scanner for conducting non-invasive diagnostic procedures of bodily tissue. Both transmission and emission studies are performed on a single scanner utilizing software modules for each kind of study. Dual energy x-ray and radioactive sources are used to perform radiographic and absorptiometry transmission measurements. A system and method of identifying regions of interest within tissue being scanned and recording the location of those regions provides an additional diagnostic capability.

Abstract: The improved apparatus for writing information on X-ray films comprising:means for exposing said X-ray films to write said information,means for identifying a type of said X-ray films, andmeans for adjusting an amount of exposure of said means for exposing in accordance with said means for identifying.

Abstract: A sheet of x-ray film in a film cassette is identified with patient data by first providing such data to a data carrier, such as an LCD unit, mounted on the cassette and facing away from the cassette. Then the film that is removed from the cassette in a light-tight environment and exposed to the patient data in the data carrier.

Abstract: This invention relates to an orbital aiming device for aiming a puncturing instrument to a targeted object for use with a fluoro X-ray apparatus isocentric in at least one direction.The orbital aiming device in order to offer most advantages is isocentric about two rotational axes which point of intersection defines its isocenter and is disposed in relation to the fluoro X-ray apparatus so that its isocenter coincides with the isocenter of the X-ray apparatus.The device comprises an arm for supporting the puncturing instrument so that it aims to the isocenter, which arm is orbitaly moveable on arcuate rails for pivoting the puncturing instrument about the isocenter around one of the two rotational axes the arcuate rails are supported by a supporting means in a rotational relationship for pivoting the puncturing instrument about the isocenter around the second rotational axis.

Abstract: An object replicator that replicates the physical form of an object in a polymer or the like by employing a Computed Tomography scanner or a Magnetic Resonance Imaging system, to digitize the physical features of the object to be copied. This data is used to form an electronic three-dimensional representation of the object. The electronic representation is then sectioned and provided to a three-dimensional printer to replicate a copy of those features by sequentially forming and joining laminae corresponding to the sections, to build up a physical replication of the object in a step-wise fashion whereby the three dimensional object is auto-matically formed from a composite of laminae.

Abstract: A radiographic film cassette exposes a sheet of film to X-rays projected along an X-ray path by an X-ray tube. The cassette has an inner surface defining a recess for receiving the film sheet. A base having an inner surface is adapted to close upon the cover for securing the film sheet. A key is permanently mounted to the cover and disposed within the recess to provide the recess with chiral asymmetry. The sheet of film has a cutout adapted to engage the key. A marker is permanently fixed along at least one edge of the film. The key is so mounted that its disposition within the recess permits engagement with the cutout in only one orientation of the film sheet therein. The marker has chiral asymmetry and cooperates with the key and the cutout to identify the side of the film sheet facing the X-ray tube during exposure.

Abstract: An X-ray label includes a substrate that is transparent to X-ray radiation and X-ray absorbing pigment deposited on the substrate in images that provide identification data under visible light and that create corresponding images in an X-ray film emulsion layer when the film is exposed to X-ray radiation. Preferably, the X-ray absorbing pigment is deposited on the substrate using a thermal print process to quickly and consistently transfer X-ray absorbing pigment characters from the ribbon to the X-ray transparent substrate.

Abstract: A data acquisition system is disclosed for use in radiographic imaging. The acquisition system includes at least two memory banks for storing radiographic data from a radiation detector, acquisition circuitry for sensing radiographic data when transmitted by the detector and for writing such data into one of the memory banks, and a controller for selecting a memory bank for storage of the data, and for switching from one memory bank to another, as well as for reading data from one or the other memory banks when such memory bank is not actively acquiring data.

Abstract: An x-ray apparatus including an x-ray source with a primary radiation diaphragm attached thereto has a luminescent foil disposed in the interior of either the x-ray source or the primary radiation diaphragm at a location so that the x-ray beam is incident thereon. Interaction of the luminescent foil with the x-ray beam causes the foil to emit light, which is conducted to an exterior of the apparatus by an optical waveguide. The light is therefore visible at a location at the exterior of the unit, such as in the housing, as a reliable indicator that x-rays are actually being generated.

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.

Abstract: A lithotripter has a source for focussed shockwaves and an X-ray device which is mounted for relative displacement and positioning in relation to that source of shockwaves; an improvement includes a device for aiming and sighting in cooperation with the X-ray equipment that includes a carrier element defining a first pair of X-ray contrasting aligned reference points and two additional X-ray contrasting reference points, on a second line and intersecting the first line at a point of intersection at about 15 to 45 degrees; and that aiming and sighting device is mounted in relation to said source of focussed shockwaves such that the point of intersection coincide with a focal point of the shockwave source.

Abstract: Marking tape adapted for use in autography, comprising: a substrate having an upper surface, a phosphorescent coating applied to the upper surface, the coating including phosphor powder grains, the grains phosphorescing with light at a wavelength between 400 and 600 nm upon exposure to UV or visible light, the phosphorescing occurring for a period of at least 5 minutes after the exposure, the concentration of the grains being sufficient to emit sufficient photons and thereby cause X-ray film having a sensitivity of 2000 EI to darken to an optical density of between 0.2 and 3.0.

Abstract: A device for producing plural lines on a film bearing a radiographic image of a portion of the body of a living being to facilitate the location of a part of the being's body within that image. The device comprises a flexible substrate formed of a porous, translucent or transparent material having lines of a radio-opaque material disposed thereon and is made by the application a slurry of a plastisol material and lead particles in the line pattern on the substrate and then drying the slurry. The device is used by applying it over a selected portion of the body of a being, disposing a radiosensitive film under the selected portion of the being's body, exposing the film to radiation, and thereafter developing the film. The resulting radiographic image of the selected portion of the being's body thus has indicator lines crossing it which facilitates the demarcation of a desired portion of that image. A marking instrument, e.g.

Abstract: An X-ray fluoroscopic apparatus comprises an X-ray tube for emitting X-rays to an object to be examined, an image intensifier for converting an X-ray image of the object to an optical image, a TV camera for picking up the optical image through a light-tight optical system coupled to the output portion of the image intensifier, an A/D converter for converting an output analog signal of the TV camera to a digital image signal, a selector for outputting the output of the A/D converter to its first and second outputs, an offset memory connected to the first output terminal of the selector, a subtracter for subtracting the output of the offset memory from the second output terminal of the selector, and an image memory to which the output of the subtracter is supplied. When no X-rays are emitted, the selector is connected to the side of the first terminal and an offset signal for each of pixels for one frame output from the TV camera is written into the offset memory.

Abstract: In a tomographic image diagnostic apparatus, a region of interest is automatically set on a tomographic image by recognizing actual positions of a phantom based upon CT (computerized tomographic) values of the phantom. The phantom is made of a base portion having a first reference CT value and a plurality of rods each having a second reference CT value. The region of interest is defined by recognizing the gravity centers of these rods.

Abstract: A data correcting device is intended to be used with a CT apparatus for obtaining a tomographic image with a subject holding means being adapted to be slidable into or out of the tunnel in a gantry. The device includes a body movement sensor for detecting a movement of a subject under examination; a body movement data processing unit for converting body movement data from the body movement sensor into address correcting data; a tomographic data processing unit for processing tomographic data obtained in the gantry; an address converting unit for correcting the address of the tomographic data with the address correcting data; and a memory for storing data.

Abstract: Positions of marker images included in two images obtained by a digital radiography system are detected by a marker position detecting section. The marker image intervals in each image are calculated by an extension rate correcting section in accordance with the detected positions of the marker images. Reduction/extension for one image is perfomed in accordance with the extension rate of the image obtained by a ratio of the calculated marker image intervals, thereby coinciding extension rates of two images.

Abstract: A fail-safe X-ray film marking system that includes a reusable fastening combination adapted for use in temporarily fastening a marking element to a container that is configured for holding X-ray film. The marking element is at least partially opaque to X-rays, and it is adapted to be positioned on the cassette in such a way that an image of an identifying character of the marking element will be imprinted on the X-ray film (inside the container) after it is exposed to radiation. The fastening combination is formed from X-ray permeable material that will not degrade the quality of an image produced on the subsequently exposed X-ray film; a suitable material for the combination is nylon.The fastening combination preferably includes a relatively large sheet having a pile-like surface comprising a multitude of small, short loops of the kind that can be engaged by a multitude of resilient hooks of the Velcro type.

Abstract: The specification describes an information-bearing sheet suitable for use with an X-ray film. The sheet is formed of a mark-bearing portion, which is to be applied to the X-ray film and exposed to X-ray upon taking an X-ray picture of an object, and a data-filling portion bearing, in a form printed thereon, the same mark as the mark-bearing portion, containing at least one blank space adapted to fill identification data of the object and provided in combination with the mark-bearing portion. The mark may be printed with a lead-containing ink on the mark-bearing portion. When the X-ray film is exposed to X-ray with the mark-bearing portion applied thereon, the mark is automatically imprinted on the X-ray film. When taking the X-ray picture, the data-filling portion is filled with appropriate data on the object and is applied to a bag for storing or filing the X-ray picture. In this manner, the X-ray picture can be easily matched with its corresponding object without failure.

Abstract: An X-ray tube exposure monitor for recording the emissions from a diagnostic X-ray tube. A photo diode is mounted inside the X-ray tube bulkhead and detects radiation from the X-ray tube. The photo diode is connected to a high gain amplifier and, in response to radiation being detected, the output of the amplifier sends an electronic signal to a microprocessor. The microprocessor records the emission duration and the temperature of oil around the X-ray tube and increments an exposure count. The recording and exposure count is stored in non-volatile memory which is read later by a service technician.

Abstract: A device for producing plural lines on a film bearing a radiographic image of a portion of the body of a living being to facilitate the location of a part of the being's body within that image. The device comprises a flexible substrate having lines of a radio-opaque material disposed thereon and is made by the application a slurry of a plastisol material and lead particles in the line pattern on the substrate and then drying the slurry. The device is used by applying it over a selected portion of the body of a being, disposing a radiosensitive film under the selected portion of the being's body, exposing the film to radiation, and thereafter developing the film. The resulting radiographic image of the selected portion of the being's body thus has indicator lines crossing it which facilitate the demarcation of a desired portion of that image. In one preferred embodiment the substrate of the device includes plural openings in the lines so that a marking instrument, e.g.

Abstract: A device for attachment to an X-ray film cassette to indicate whether or not the film has been exposed to X-radiation comprises a phosphor screen (12) which fluoresces on exposure to X-radiation. A photocell (14) detects the light emitted by the screen and generates a control signal which is used to alter the display status of a liquid crystal display (24) from a first condition which indicates that the film in the cassette has not been exposed to X-radiation to a second condition where it indicates that exposure has taken place. A latch circuit (20) is used to retain the altered display even after exposure to X-radiation ceases. The device therefore gives a clear indication of whether or not the film in the cassette has been exposed to X-radiation. The circuit is powered from a nickel cadmium cell (26), the power supply circuit of which incorporates a micro switch (28).

Abstract: An x-ray video system for the transillumination of an examination subject has an x-ray system which generates a transillumination image of a patient using an x-ray beam having a central ray, a diaphragm for gating the x-ray beam which has a number of plates, each moveable relative to the central ray, a signal generator associated with each plate which generates a signal corresponding to the position of the associated plate relative to the central ray, a mixer for combining the plate position signals with the transillumination image, and a display which generates the transillumination image with the position signals mixed therewith in the form of marks on the transillumination image.

Abstract: Method and apparatus for marking a film with information, e.g. patient data and other possible information in X-ray photography, such as panoramic tomography. The X-ray beam creating the X-ray photograph, and the X-ray film move in a certain manner in relation to one another. A certain area of the film is reserved for markings which are latently made thereon, to become visible when the X-ray film is developed. Markings are made simultaneously with the film exposure to the X-ray beam for the X-ray photography. The markings are sequentially made by using relative movement of the radiation with which the marking is made upon the film and the film itself, such relative movement being synchronized with the relative movement of the X-ray beam to which the film is exposed for the actual X-ray photography, and the film itself, the relative movement preferably representing a parallel deflection or displacement along a marking row.

Abstract: A scintillation camera apparatus adapted for displaying an image representing a radioisotope distribution within a subject under examination at a substantially constant level in image density during a persistent data acquisition procedure comprises an auxiliary memory for sequentially storing position signals representing detected positions of gamma rays, and an image memory for storing a count representing the frequency of detection of gamma rays in a memory location accessed by position signals. The auxiliary memory has a predetermined capacity, and thus, when the number of the sequentially stored position signals exceeds this memory capacity, the earliest-entered position signals stored therein are made to overflow therefrom. A memory controller accesses a location in the image memory by means of the overflowed position signals and decrements the content at the accessed location.

Abstract: A crayon-like marker is described which is capable of making marks detectable by X-ray on various substrates, e.g., textile products. The marker is comprised of a waxy medium in which is dispersed a radio-opaque substance. Additional coloring agents may be added if desired.

Abstract: The present invention relates to a gauge for use with x-ray machines to calibrate correct technic values (exposure, kilovoltage, processing conditions, etc.) for x-ray film to yield anatomically correct film densities over the visible density range. The gauge accomplishes this by including only four sections. In particular, a first portion for achieving correct film densities at the low end of the visible density range and a second portion for achieving correct film densities at the high end of the visible density range. The gauge also includes at least one region for achieving a slight variation in film density in each of the first and second above-named portions. The gauge may be encased by being cast in plastic of a particular thickness and absorption of x-rays. With this gauge, the radiographer examines film densities at the upper and lower limits of the visible density range to distinguish overexposure, upper limits of correct exposure, correct exposure, lower limit of correct exposure and underexposure.

Abstract: An aperture device defines X-ray beams emitted from X-ray focal points L and R spaced apart from each other along the first direction. This defining operation is performed along the first direction and a second direction crossing the first position, thereby shaping a rectangular X-ray radiation area. Blades defining the two edges of the X-ray beam along the first direction and blades defining two edges of the X-ray beam along the second direction are supported by engaging portions into which screw portions of screw rods are screwed and engaging portions slidably fitted around round portions of the screw rods, respectively. When the screw rods are rotated by activation of corresponding stepping motors, the corresponding engaging portions are moved parallel to the screw rods. The respective blades can be variably moved along the first or second direction, thereby forming an X-ray radiation area having any shape in any position.

Abstract: A substrate transparent to x-rays mounts a resilient layer transparent to x-rays, and an overlying thin blocker layer of fracturable lead or tin foil which is opaque to x-rays. When impressed or typewritten the blocker layer is selectively stenciled or fractured to permit selective passage of x-rays therethrough. The substrate or a perforated portion thereof mounting the stencil, is emplaced upon an x-ray cassette during x-ray exposure to capture the stencilized data in the permanent film image. Visual inspection of stencilized data may be aided by a white paint layer disposed upon the blocker layer. Affixation to the film or cassette may be aided by a pressure sensitive adhesive layer in an area adjacent the other superimposed layers.

Abstract: In a radiation image recording and reproducing method wherein a plurality of stimulable phosphor sheets are reused by repeated circulation through a radiation image recording step, a radiation image read-out step, and an erasing step, each stimulable phosphor sheet is provided with its own identifying code and each time a visible image is reproduced the identifying code of the stimulable phosphor sheet on which the corresponding radiation image was stored is simultaneously reproduced, thereby enabling identification of sheets requiring replacement. The number of times each sheet is subjected to image readout is counted, and sheets are selectively removed after they circulate a predetermined number of times indicative of sheet wear out.

Abstract: A method and apparatus for simply, rapidly and reliably determining the diagnostically relevant quality and the general reliability of X-ray mammograms. A mammogram quality reference test standard is provided in which particulate matter of selectable form, composition and size is temporarily affixed on the breast itself for exposure to radiation during production of a diagnostic mammographic radiograph. In a preferred embodiment of the invention, the test standard utilizes particulate matter which includes smaller particles useful in evaluating resolution in the film as well as contrast, and larger particles useful primarily in evaluating contrast in the film. The test zone itself is clearly delineated by suitable, easily visible markers so as clearly to be identifiable, and the area occupied by the test standard is preferably kept small so as to ensure a minimum of interference with a viewing of the image of the tissues of the breast.

Abstract: A stereo tactic frame for use with fluoroscopy is utilized to aim and guide a puncturing tool to a target located within a body. An aperture within the frame is positioned to overlie the target when viewed on a fluoroscopic image display. The frame is then rotated about two axes so that the aperture plane is made perpendicular to the beam passing through the aperture, wherein the center of the aperture is made to align with the target object.

Abstract: A guide for locating a target object within a visually opaque but x-ray transparent object has a base creating a first reference plane. A vertical post extends upward from the base perpendicular to the first reference plane. First target sighting members, which are at least partially opaque to x-ray are mounted for movement relative to the vertical support member and provide for creating a line parallel to the reference plane through the target. A system is provided for aligning x-ray fluoroscope with the first target. A second target has two target sighting members, one on an arm above the target object and the other on an arm below the target object. The x-ray fluoroscope is aligned with these such that when the x-ray fluoroscope is projecting in a line parallel to the upright support and perpendicular to the reference plane, it extends through opaque sights and through the target.

Abstract: The apparatus enables the taking of multiple X-ray photographs of the legs and pelvis of a patient. A platform is rotatably mounted on a base member, and is provided with means for keeping the patient still in a standardized standing position. With only minor vertical and horizontal adjustment of an associated substantially point source of X-rays, side and front X-rays can be taken without movement of the patient, apart from rotation of the platform. Radio opaque marker means provided on otherwise radio-transparent spaced screens produce, on the X-ray film, images which can be interpreted to provide information for compensation of distortions in images on the X-ray film due to the use of a point source of radiation.

Abstract: Markers for providing reference points or lines are recorded together with radiation images on stimulable phosphor sheets in a position fixed with respect to the radiation images. The stimulable phosphor sheets are scanned with stimulating rays, and the spatial coordinates of reference points or lines are detected from digital data of the images detected from light emitted from the stimulable phosphor sheets. Rotation and shift among the radiation images are calculated based on the reference points or lines. One of the radiation images is rotated on the digital data when positional deviation exists and moved on the digital data when positional deviation exists. Subtraction of the image data is then conducted among the corresponding picture elements of the radiation images to extract an image of a specific portion of the radiation images.

Abstract: A radiation image and read-out apparatus comprises a conveying means for circulating stimulable phosphor sheets along a predetermined circulation path, an image recording section for recording radiation images of objects on the sheets, an image read-out section for reading out the radiation images from the sheets, an erasing section for releasing radiation energy remaining on the sheets, a sheet position detection means for outputting sheet position data, an object data input section for receiving data related to the objects, and a signal output control circuit for receiving the object data and the sheet position data, storing the object data in association with the sheet positioned at the image recording section at the time the object data is received, reading out the object data stored in the memory means in association with the sheets at the time the radiation images are read out in the image read-out section, and outputting data signals corresponding to the object data for the respective sheets together w

Abstract: An X-ray film marking device is quickly attachable to and detachable from an X-ray film cassette using a block of magnet material which is X-ray opaque but if formed with two X-ray transparent cavity portions. One cavity portion is L-shaped to cause a black L recording on a white background. A second cavity portion is R-shaped to cause a black R recording on a white background. A door of X-ray opaque material is adjustably positioned over either cavity portion and has magnetizable material cooperating with the magnet material to safely lock the door in its adjusted positions. The cavity portions are filled with different color X-ray transparent material for contrast. The magnet material includes a third cavity portion which is dish shaped for confining a ball that is free to move to a position therein depending upon the orientation of the X-ray cassette upon which the marker is mounted.

Abstract: A localizer system is described which enables determination of the coordinates of a target located inside the human body and visualized on a tomographic scan image for essentially any arbitrary scan plane through the body. It involves a means of fixing a frame in a known relationship to the body and placing the localizer system in a fixed position relative to the frame. There is an axial axis defined for the localizer, and there are both parallel and transverse (perpendicular) rod elements as well as diagonal rod elements on the localizer. These appear as spot images on the scan plane image and are sufficient in number and location to enable accurate calculation of a target image on the scan and determination of the target coordinates in space relative to the localizer. This applies to plane scan cuts which are substantially parallel or perpendicular to the localizer axis.

Abstract: A system utilizing computed tomography (CT) as for surgery. A CT scanner provides data representative of or slices taken through a body member. Display apparatus reveals the slices. A reference apparatus (frame) affixed to the body, operates in conjunction with the scanner and the display apparatus. The frame includes: structure for affixation to the body, holder means for guiding the therapeutic instrument, and structure for providing reference indications. The system further includes a data processing structure and control means for transforming data between frame coordinates and slice coordinates.

Abstract: The isocenters of two independent frontal and lateral viewing X-ray systems are made coincident using an X-ray permeable target frame that has congruent crosshairs defined by X-ray impermeable lines on opposite side walls. A small steel ball is located in the frame between side walls on a line running from the intersection of one set of crosshairs to the other. A television display of the X-ray image of the ball resting on the patient supporting table top with the frame leveled and of the crosshairs with the frontal system having the central ray of its X-ray beam vertical and then horizontal and with X-ray impermeable crosshairs on the image receptor permits shifting the frame until the crosshairs on it and on the receptor are coincident with the ball and the isocenter in vertical and horizontal orientations. The procedure for establishing the isocenter of the lateral system is comparable.