The second generation HRRT - a multi-centre scanner performance investigation

• Main Authors: Sossi, V., de Jong, H.W.A.M., Barker, W.C., Bloomfield, P., Burbar, Z., Camborde, M.-L., Comtat, C., Eriksson, L.A., Houle, S., Keator, D., Knob, C., Krais, R., Lammertsma, A.A., Rahmim, A., Sibomana, M., Teras, M., Thompson, C.J., Trebossen, R., Votaw, J., Walker, M., Wienhard, K., Wong, D.F.
• Format: Conference Proceeding
• Language: English
• Subjects: Data acquisition; Decoding; Gamma ray detection; Gamma ray detectors; Hardware; Humans; Measurement standards; Performance evaluation; Radioactive decay; Stability
• ISSN: 1082-3654; 2577-0829
• DOI: 10.1109/NSSMIC.2005.1596770

The high resolution research tomograph (HRRT) is one of the most complex existing positron emission tomographs: it is the only human size scanner capable of decoding the depth of the /spl gamma/-ray interaction in the crystal, using a lutetium LSO/LYSO phoswich detector arrangement. In this study we determined basic scanner hardware characteristics, such as scanner data acquisition stability, and their variability across eleven centres. In addition a subset of the NEMA NU-2001 standards measurements was performed. We found (i) significant variability in the DOI decoding results between centres, (ii) a trend toward an increasing number of detected true coincident events as a function of elapsed time from scanner calibration likely due to a shifting energy spectrum, (iii) a count-rate dependent layer identification, (iv) scatter fraction ranging from /spl sim/ 42% to 54% where the variability was partly related to the shifting of the energy spectrum, (v) sensitivity ranging from /spl sim/5.5% to 6.5% across centres, (vi) resolution of /spl sim/(2.5 mm)/sup 3/, fairly consistent across centres, (vii) image quality which is very comparable to other scanners.