Abstract: A powered wheelchair includes a high efficiency drive mechanism for increasing the range of travel on a predetermined battery charge. Drive motors are transversely mounted relative to side frames of the wheelchair, and disposed in superimposed arrangement for varying the width of the wheelchair.

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: The radiographic system includes an x-ray source for irradiating a patient with x-radiation. An image intensifier receives the x-radiation which has traversed the patient and produces an optical image of a radiation shadowgraph of the examined area of the patient. A television camera converts the optical image into a video signal. An image processor stores each frame of the video signal generated by the television camera as an electronic image of the optical image viewed on the image intensifier. Alternately, a plurality of frames from the television camera may be combined to produce a composite image. A bias light is provided adjacent the target of a television camera to illuminate the target before an optical image from the image intensifier is monitored by the television camera. This improves the linearity of the response of the television camera, particularly to low amplitude light intensities on the first few video frames generated by the camera.

Abstract: Disclosed is a collimator for a tomographic scanner which performs the collimator function of dividing a fan of radiation into a multiplicity of finger beams and the attenuator function of causing a generally bell-shaped radiation energy distribution across a scan circle. The collimator has larger effective apertures for forming radiation into finger beams to traverse the center of the scan circle than for forming finger beams to traverse the edges of the scan circle. The width of the collimator apertures are defined by radially oriented vanes arranged along a circular arc. By offsetting the radiation source from the geometric center of the circular arc, the vanes defining the width of some apertures are more skewed than others relative to the radiation paths.

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: A control and take-up mechanism for controlling and protecting at least one elongated cable and the like which may be employed to supply operating power, fluids, controls and so on to an operating member mounted within an apparatus and wherein the operating member is selectively movable within the apparatus through an operating plane between a first position and a second position spaced therefrom. The take-up mechanism is comprised of an arcuate cable trough fixedly mounted to the apparatus in a plane parallel to the operating plane with a portion of the elongated cable leading to the operating member longitudinally disposed therein. A cable wheel assembly is received in the trough in rolling engagement therewith and includes a hub and opposed sides which define a cable channel therebetween.

Abstract: An automatic variable collimator which controls the width and thickness of X-ray beams in X-ray diagnostic medical equipment, and which is particularly adapted for use with computerized axial tomographic scanners. A two-part collimator is provided which shapes an X-ray beam both prior to its entering an object subject to radiographic analysis and after the attenuated beam has passed through the object. Interposed between a source of radiation and the object subject to radiographic analysis is a first or source collimator. The source collimator causes the X-ray beam emitted by the source of radiation to be split into a plurality of generally rectangular shaped beams. Disposed within the source collimator is a movable aperture plate which may be used to selectively vary the thickness of the plurality of generally rectangular shaped beams transmitted through the source collimator.

Abstract: A versatile patient table system for transverse axial scanners employs front and rear tables with a spanning patient pallet for abdominal scans. A motorized conveyer belt on the front table increments the axial position of the patient. For brain scans the rear table and patient pallet are replaced by a head restraint assembly with a hinged headrest, check pad restraint members and a body pad which rests on the conveyer belt on the front table. In the automatic mode of operation, the belt moves either the body pad or the patient pallet out from the scanner in controlled increments triggered by the image processor. The hinged metal seam of the belt is used for indexing the extreme outward and inward positions.

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.