Technicare Corporation

Ohio Nuclear, Inc.

Other

Bios Corporation

Reality Imaging Corporation

Robert H Wake

Joseph B Richey

John T Keller

Richard M Kovacs, Jr

Thomas R McBride

Ronald G Walters

James M Bradcovich

Carlos D Pinkstaff

Henry N Wagner

Kendall A Smith

Willard F Hunt

Michael C Cheiky

Eugene J Senger

Robert H McCarthy

Stephen C Gottschalk

Henry H Wilson

Steven L Cool

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. By adding a selectable adder to the input of the z-buffers, normal z-buffer operation may be selected or a radiographic mode utilizing the entire width of the z-buffer to hold an accumulated intensity may be selected.

Imager and process

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. By adding a selectable adder to the input of the z-buffers, normal z-buffer operation may be selected or a radiographic mode utilizing the entire width of the z-buffer to hold an accumulated intensity may be selected.

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.

Cardiac imaging with CT scanner

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.

Non-circular emission computed tomography

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.

Support structure for rotatable scintillation detector

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.

Method of multiplanar emission tomography and apparatus therefor

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.

Variable persistance video display

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.

Data channel multiplexing system for CT scanner with rotating source

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.

Nuclear cardiac blood volume detecting apparatus

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.

Dynamic uniform flood correction for radioisotope cameras

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. The radiation is correlated between the first scan and the second scan. In order to reduce artifacts, the perimeters of the areas under consideration are oscillated with a saw-tooth wave. The apparatus includes a radiation sensing device for scanning a section of radiation, normally an irradiated patient. The radiation sensing device includes a camera detection head and has a collimator which channels radiation, normally gamma radiation, from the patient to a scintillation crystal operatively attached thereto. The scintillation crystal converts gamma radiation to light radiation which is noted by photomultiplier tubes viewing the scintillation crystal. Electrical responses given by the photomultiplier tubes are operatively attached to means for operating on the electrical impulses to create a signal which gives an indication of the relative location of the radiation. A drive means moves the camera head in a longitudinal direction along a cot supporting the patient. At each end of the mechanical movement of the head, an electronic scanner views the ends of the section of radiation under consideration. Appropriate mechanical drive means moves or indexes the table supporting the patient in a direction transverse to the longitudinal movement of the detector head. A means for blending the radiation received from multiple passes of the detector head includes an electronic mask with oscillating sides. In this manner, multiple passes can be blended without substantial artifacts. A means for sequencing events governs the proper order of events.

Growing community of inventors

Solon, OH, United States of America

Robert H Wake