Comparative analysis of iterative reconstruction algorithms with resolution recovery for cardiac SPECT studies. A multi-center phantom study

Abstract

This is the first study comparing the relative performance of different, commercially available, IRR software, over a wide range of count statistics; the additional effect of scatter and attenuation corrections, alone or in combination, was also evaluated. Our results confirm that IRR algorithms produce substantial benefits with respect to conventional FBP or OSEM reconstruction methods, as assessed through different figures of merit, in particular when SC and/or SCAC are also included.

Advances in image reconstruction software in nuclear cardiology: Is all that glitters gold?

“…This could be due to the fact that the different manufacturers seem to emphasize different aspects of the myocardial image quality. 24 As a matter of fact, the experimental results obtained in phantom studies show that IRR algorithms produce better results than conventional FBP and OSEM in terms of lesion contrast, wall thickness and noise indices, independently from the scanner/software combination considered. 24 Moreover, the best results are obtained applying attenuation and scatter corrections, a practice still performed by the minority of laboratories.…”

“…24 As a matter of fact, the experimental results obtained in phantom studies show that IRR algorithms produce better results than conventional FBP and OSEM in terms of lesion contrast, wall thickness and noise indices, independently from the scanner/software combination considered. 24 Moreover, the best results are obtained applying attenuation and scatter corrections, a practice still performed by the minority of laboratories. As a final point, also the polar maps obtained by these different models are significantly different; consequently, normal reference databases must be specifically implemented for each algorithm and system used.…”

“…23 The performances of the different coupled hardware-software systems available in the market have been investigated in a experimental phantom study. 24 It was demonstrated that there is an effective dependence of the image quality indexes from the scanner/software combination, which is not univocal but also depends on the image quality index considered. This could be due to the fact that the different manufacturers seem to emphasize different aspects of the myocardial image quality.…”

Automatic evaluation of myocardial perfusion on SPECT: Need for “Normality”

“…16 Image quality is further improved by the implementation of resolution recovery algorithms, additively reducing image noise with respect to conventional reconstruction software. While the additive value of novel iterative resolution recovery (IRR) reconstruction algorithm may be limited in high-count SPECT studies, it becomes relevant in the case of lowdose SPECT scans, where the improvement with respect to FBP becomes more relevant.…”

The long way to dose reduction in myocardial perfusion imaging

“…[2][3][4][5][6] The recommended activities, per single scan, according to the American Society of Nuclear Cardiology (ASNC), may now range from 148 MBq (stress-only protocol, new technology, body mass index (BMI) = 25 kg/ m 2 ) to 1332 MBq (second injection in a one-day stress/rest protocol, GP gamma camera, BMI = 35 kg/m 2 ), resulting in effective doses of between 1.0 and 10.5 mSv. 7 However, the IRR algorithms have demonstrated the potential to reduce the patient dose below 50% of the reference in an anthropomorphic phantom study 8 and in two clinical studies, 9,10 mostly in the presence of normal-weight patients (between 18.5 and 24.9 kg/m 2 of BMI). The study of Juan Ramon et al 11 in this issue of the Journal of Nuclear Cardiology is the first study that investigates the extent to which patient dose can be reduced in cardiac SPECT through the optimization of reconstruction process.…”