Digirad | Date: 2010-11-17
Digirad | Date: 2010-04-20
A SPECT system which scans over multiple separate scans and individually motion compensates the information obtained from each of these scans. The separate scans may be over different angular extents and may be for different purposes. One of the scans for example may be a scout scan, and the other scans may then be scans which concentrate on areas identified during the scout scan. Alternatively, the scans may all being exactly the same and stitched together after the individual motion compensation. Since each of the scans are shorter, the patient will presumably have moved less during each individual scan, and the amount of motion is hence presumably less.
Digirad | Date: 2012-04-25
First and second gamma radiation detector heads are oriented to image an area of a subject. The area of said subject is completely within a field of view that is defined between the first and second gamma radiation heads. Focal points of each of the first and second gamma radiation heads are also within an area defined between the first and second gamma radiation heads. A computer is programmed to receive image information from both the first gamma radiation detector head and the second gamma radiation detector head, and operating to use information from both the first gamma radiation detector head and the second gamma radiation detector head, as well as to use information indicative of a distance between the first gamma radiation detector head and the second gamma radiation detector head, to determine a location of an item of interest in the subject and between the first gamma radiation detector head and the second gamma radiation detector head, by calculating using information about similar triangles formed from known positions of the first gamma radiation detector head and the second gamma radiation detector head, and the information.
Digirad | Date: 2015-11-10
Solid state gamma cameras and gamma detectors for medical diagnostic use; diagnostic instruments, namely, imaging probes for medical diagnostic imaging and parts and fittings thereof; rotating platform chairs for use in medical diagnostic imaging. Installation, maintenance and repair of medical imaging apparatus and diagnostic instruments. Installation, maintenance and updating of computer software for medical imaging. Medical diagnostic testing services in the field of mobile nuclear cardiology, ultrasound, echocardiography, vascular imaging, and neuropathy.
Bai C.,Digirad |
Conwell R.,Digirad |
Kindem J.,Digirad |
Babla H.,Digirad |
And 6 more authors.
Journal of Nuclear Cardiology | Year: 2010
Background: We developed a cardiac SPECT system (X-ACT) with low dose volume CT transmission-based attenuation correction (AC). Three solid-state detectors are configured to form a triple-head system for emission scans and reconfigured to form a 69-cm field-of-view detector arc for transmission scans. A near mono-energetic transmission line source is produced from the collimated fluorescence x-ray emitted from a lead target when the target is illuminated by a narrow polychromatic x-ray beam from an x-ray tube. Transmission scans can be completed in 1 min with insignificant patient dose (deep dose equivalent <5 μSv). Methods: We used phantom studies to evaluate (1) the accuracy of the reconstructed attenuation maps, (2) the effect of AC on image uniformity, and (3) the effect of AC on defect contrast (DC). The phantoms we used included an ACR phantom, an anthropomorphic phantom with a uniform cardiac insert, and an anthropomorphic phantom with two defects in the cardiac insert. Results: The reconstructed attenuation coefficient of water at 140 keV was .150 ± .003/cm in the uniform region of the ACR phantom, .151 ± .003/cm and .151 ± .002/cm in the liver and cardiac regions of the anthropomorphic phantom. The ACR phantom images with AC showed correction of the bowing effect due to attenuation in the images without AC (NC). The 17-segment scores of the images of the uniform cardiac insert were 78.3 ± 6.5 before and 87.9 ± 3.3 after AC (average ± standard deviation). The inferior-to-anterior wall ratio and the septal-to-lateral wall ratio were .99 and 1.16 before and 1.02 and 1.00 after AC. The DC of the two defects was .528 and .156 before and .628 and .173 after AC. Conclusion: The X-ACT system generated accurate attenuation maps with 1-minute transmission scans. AC improved image quality and uniformity over NC. © 2010 American Society of Nuclear Cardiology.