The ECAT ART Scanner for Positron Emission Tomography. 1. Improvements in Performance Characteristics.

PET Facility, Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
Clinical Positron Imaging 02/1999; 2(1):5-15. DOI: 10.1016/S1095-0397(98)00057-0
Source: PubMed

ABSTRACT The widespread use of positron emission tomography (PET) has been to some extent limited by the cost and complexity of PET instrumentation. Recognition of the wider applicability of clinical PET imaging is reflected in the ECAT ART design, a low cost PET scanner targeted for clinical applications, particularly in oncology. The ART comprises two asymmetrically opposed arrays of BGO block detectors. Each array consists of 88 (transaxial) by 24 (axial) crystals, and the arrays rotate continuously at 30 rpm to acquire a full 3D projection data set. Sensitivity and count rate limitations are key performance parameters for any imaging device. This paper reports on improved performance characteristics of the ART, achieved by operating the scanner with a decreased block integration time, reduced coincidence time window, and collimated singles transmission sources. Compared to the standard ART configuration, these modifications result in both improved count rate performance and higher quality transmission scans.

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