Intra-patient reproducibility of myocardial SPECT imaging with 201Tl

• Published in: Journal of nuclear cardiology 2009, Vol.16 (1), p.97-104
• Main Authors: Backus, Barbra E., Verburg, Frederik A., Romijn, R. Leo, Konijnenberg, Mark W., Beekman, Freek J., Verzijlbergen, J. Fred
• Format: Article
• Language: English
• Subjects: Cardiology; Female; Heart Ventricles - diagnostic imaging; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Imaging; Male; Medicine; Medicine & Public Health; Middle Aged; Nuclear Medicine; Original Article; Phantoms, Imaging; Radiology; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Thallium; Tomography, Emission-Computed, Single-Photon - instrumentation; Tomography, Emission-Computed, Single-Photon - methods
• ISSN: 1071-3581; 1532-6551
• DOI: 10.1007/s12350-008-9011-7

Background To define the physical and clinical reproducibility of 201 Tl myocardial perfusion SPECT (MPS), this study assesses the variation between two repeated rest 201 Tl MPS with repositioning only, with a two-hour time interval and with phantom measurements as a reference. Methods Three anthropomorphic thorax phantoms were filled with 201 Tl. For each phantom five repeated 201 Tl MPS were obtained. In addition, in 20 patients repeated 201 Tl rest-MPS and in 26 patients early and delayed 201 Tl rest-MPS were performed. Quantitative analysis was done using MunichHeart. Statistical methods were used to calculate variability. Visual analysis was performed by 2 independent observers. Results The average variation between repeated phantom MPS was 0.5% (95% confidence interval (CI): −0.4% to 1.4%). For patient scans this was −5.0% (95% CI: −2.5% to −7.5%) and between early and delayed 201 Tl MPS −15.5% (95% CI: −11.7% to −19.3%). Visual assessment revealed no clinical significant differences between rest 201 Tl and repeated or delayed 201 Tl MPS. Conclusions Repositioning in phantom 201 Tl MPS does not cause significant variation. Repeated 201 Tl MPS in patients shows 5.0% decrease of 201 Tl in 30 minutes, which increases to 15% during a two-hour time interval without quantitative or visual regional differences. This decrease indicates a time-related washout of 201 Tl, but does not change clinical diagnosis.