Abstract: A detector array for use in a laser imaging apparatus, comprises a plurality of housings disposed in an arc around an opening in which an object to be scanned is disposed, each housing including an open front end, a rear end and a longitudinal axis; and a detector disposed within each housing at a distance from the front end, thereby to restrict the field of view of each detector. The housings are adapted to be orbited around the object about an orbit axis. Each detector is adapted to simultaneously detect light exiting from the object within the respective field of view of each detector. A method for collecting light exiting from a object being scanned with a light source is also disclosed.

Abstract: A detector array for a laser imaging apparatus comprises a plurality of detectors disposed in an arc around an opening in which an object to be scanned is disposed; and a variable gain integrator operably connected to each detector to accommodate the dynamic range of each detector. A method for collecting data for use in image reconstruction of an object being scanned is also disclosed, comprising the steps of providing a plurality of detectors disposed in an arc around the object to be scanned, including a variable gain amplifier connected to each detector; impinging a laser beam at a point on the object; integrating the input to each integrating amplifier at several time intervals; recording each output at each integration interval for use in image reconstruction; orbiting the detectors and the laser beam to a next point on a circle; and repeating steps until a complete circle has been traversed.

Abstract: A detector array for use in a laser imaging apparatus, comprises a plurality of housings disposed in an arc around an opening in which an object to be scanned is disposed, each housing including an open front end, a rear end and a longitudinal axis; and a detector disposed within each housing at a distance from the front end, thereby to restrict the field of view of each detector. The housings are adapted to be orbited around the object about an orbit axis. Each detector is adapted to simultaneously detect light exiting from the object within the respective field of view of each detector. A method for collecting light exiting from a object being scanned with a light source is also disclosed.

Abstract: An apparatus for determining the perimeter of an object being scanned comprises a scanning chamber for receiving therein an object being scanned; a source of laser beam disposed within the scanning chamber for impinging on the object being scanned, the laser beam being adapted to orbit around the object; an array of sensors disposed within the chamber, each of the sensors being adapted to detect light emanating from the surface of the object due to the laser beam exiting from the object; and each of the sensors being disposed such that at least only one of the sensors generates a peak response to light emanating from a point on the surface at a predetermined distance from a reference point, such that at each angular position of the laser beam in the orbit, a specific point at a distance from the reference is determined, thereby to generate a set of points representing the perimeter of the surface after a complete orbit.

Abstract: An apparatus for determining the perimeter of an object being scanned comprises a movable arm adapted to follow the surface of an object being scanned as the arm is orbited around the object; the arm having one end being adapted to maintain contact with the surface as the arm is orbited around the object; and an encoder operably connected to the arm for determining the movement of the lever arm at each angular position around the object. An opaque cup is positioned at one end of the lever arm immediately over a point on said surface at which a laser beam impinges on the surface of the object being scanned such that reflection from the surface is retained within the cup.

Abstract: A method for collecting data for use in image reconstruction of a tissue being scanned containing cancer cells comprises the steps of providing a source of laser beam; providing a biochemical marker that selectively binds to cancer cells within the tissue; directing the laser beam toward the object being scanned; orbiting the laser beam around the object; providing a plurality of sensors adapted to simultaneously detect the laser beam after passing through the object; and limiting the sensors to detect only the radiation released by the biochemical marker after having been activated by the laser beam.

Abstract: An apparatus and process for the flexible and rapid manipulation of multidimensional data. Coordinates are transformed by the use of a plurality of transform memories, each being addressable by a coordinate of an n-tuple. Each memory provides an intermediate value that when added to others provides a transformed coordinate. This eliminates the need for high-speed multipliers. The transform memories are additionally addressable by flags and tags associated with the location, attribute or object of interest. Different transformations take place depending on the values of the flags and tags. This allows flexible manipulation of the data. Z-buffering is done at high speed in parallel with the results being combined in efficient combiner circuits. In addition, this parallel operation permits the transformations themselves to be done in parallel.

Abstract: An apparatus and process for the flexible and rapid manipulation of multidimensional data is disclosed. Coordinates ae transformed by the use of a plurality of transform memories, each being addressable by a coordinate of an n-tuple. Each member provides an intermediate value that when added to others provides a transformed coordinate. This eliminates the need for high-speed multipliers. The transform memories are additionally addressable by flags and tags associated with the location, attribute or object of interest. Different transformations take place depending on the values of the flags and tags. This allows flexible manipulation of the data. Z-buffering is done at high speed in parallel with the results being combined in efficient combiner circuits. In addition, this parallel operation permits the transformations themselves to be done in parallel.

Abstract: The patient's ECG signal is employed in a traverse-and-rotate type CT scanner as a time base for triggering the beginning of a traverse such that the traveling beam reaches the heart at a desired phase of the cardiac cycle. For a purely-rotational-type CT scanner, continuously generated scan data is only stored for corresponding phases of successive cardiac cycles. Alternatively, gating of the beams themselves can be controlled by the ECG signal. The use of a pacemaker to stabilize the cardiac period is described along with a system for recognizing unacceptable variations in the cardiac period. In a traverse-and-rotate-type fan-beam CT scanner, the effective beam width is narrowed to hasten the traverse of the heart.

Abstract: A radiation imaging system including a rotatable scintillation detector for non-circular emission computed tomography. The radiation imaging system includes a rotatable scintillation detector and a linearly movable detector stand. With the stand stationary, the scintillation detector is capable of circularly orbiting about the longitudinal axis of the patient for emission computed tomography and with the detector stationary the detector stand may be linearly displaced for whole body scanning with the patient aligned parallel to the detector stand path in an orientation orthogonal to the tomographic orientation. The circular rotational motion is combined with the linear translation such that the detector orbits about a section of the patient in a non-circular path. The path assures a minimum distance between the face of the scintillation detector and the boundary of the patient during the entire tomographic orbit to thereby improve resolution of the tomogram.

Abstract: A curved beam apparatus adapted for mounting thereon a scintillation detector. The apparatus comprises a circular C-arm which is balanced with a counterweight at one end and a scintillation detector pivotally mounted by means of a yoke at the other end. The C-arm is mounted in a carrier member which in turn is attached to a base. The carrier member is rotatable about an axis passing through its center. In addition, the C-arm rotates circumferentially along a plane defined by the shape of the C-arm and intersecting said axis. The combination of the rotation of the C-arm and the rotation of the carrier member permits the scintillation detector to be quickly and easily manually positioned to any desired location on an imaginary sphere surrounding a portion of patient to be examined.

Abstract: A method of emission tomography using a gamma camera and a rotating collimator having an array of a large number of slanted, small diameter holes. A planar projection corresponding to each angular orientation assumed by the collimator is recorded. From these series of planar projections, a three-dimensional simulation model is reconstructed by an iterative algorithm which approximates the emitting object. The simulated model comprises multiple separable planes.

Abstract: The invention relates to a video display device which includes a memory for storing intensity values for each pixel of the video display. Connected with the memory is a persister which decreases the intensity values as a selectable function of time such that a displayed image will appear to fade. Also connected with the memory is an input for increasing specific intensity values in response to the receipt of input data corresponding to that specific display pixel. The invention further relates to a scintillation camera in combination with the video display device in which input data indicates the occurrence of a radiation caused scintillation at some corresponding coordinate position and in which the rate of image fading is consonant with the rate of data acquisition, whereby a real-time display of the passage of a radioisotope through a patient may be produced.

Abstract: A CT scanner has an outer circular array of stationary radiation detectors for an inner concentrically revolving source of radiation emitted in a fan pattern subtending a number of the detectors. A number of analog signal processing channels equal to the maximum number of subtended detectors at any given time is automatically connected via switching circuitry to receive the outputs of only the detectors within the fan pattern.

Abstract: A built up image illustrating blood volume in the heart versus time taken over many cardiac cycles is produced by continuously displaying a graph of cumulative data indicating the amount of radioactivity from a tracer in the blood detected in the heart during each of a series of intervals into which the average cardiac period is divided. The parallel lines of a raster scan display correspond respectively to the memory channels. The count stored in a particular memory channel causes the video signal for the corresponding line to be maintained at a binary level for a corresponding time interval thus generating a bar graph in which the length of each bar indicates the amount of radioactivity sensed during the corresponding interval of the cardiac cycle. As each memory channel accumulates radioactivity data with each successive cardiac cycle, each bar displayed in the bar graph lengthens to indicate the cumulative activity until an interpretable curve is obtained.

Abstract: The intrinsic nonuniformity of a radioisotope camera having an array of photomultiplier tubes viewing a scintillator crystal assembly is improved by comparing an internally generated correction factor from 1 to n, assigned to a location where a radiation event has been detected, to a random number between 1 and n and then discarding the radiation event datum if the correction factor is less than the random number. Correction factors are first generated by comparing the count at each location with an average minimum count in the presence of a uniform flood source.

Abstract: The process of this invention includes detecting gamma radiation with a radiation sensing device, converting the gamma radiation to light radiation, viewing the light radiation with photomultiplier tubes and giving electrical impulses in response thereto. The impulses are operated on to correct for any distortion and to give an indication of the relation to location of the radiation. An area of interest, for the purpose of scanning, is selected and electronically masked. During a first pass, initial scanning is done electronically without physical movement of the radiation sensing device head. After initial electronic scanning, a detector head passes over the radiation of interest while sensing radiation. At the end of the mechanical movement, an area of radiation is again electronically scanned. A cot supporting the section of radiation is moved transverse to the longitudinal movement of the head after the first pass. A scan in the opposite direction occurs similar to that in the first direction.