Head-to-head comparison of F-sodium fluoride coronary PET imaging between a silicon photomultiplier with digital photon counting and conventional scanners.

BACKGROUND

We compared silicone photomultipliers with digital photon counting (SiPM) and photomultiplier tubes (PMT) positron emission tomography (PET) in imaging coronary plaque activity with F-sodium fluoride (F-NaF) and evaluated comprehensively SiPM PET reconstruction settings.

METHODS

In 25 cardiovascular disease patients (mean age 67 ± 12 years), we conducted F-NaF PET on a SiPM (Biograph Vision) and conventional PET (Discovery 710) on the same day as part of a prospective clinical trial (NCT03689946). Following administration of 250 MBq of F-NaF, patients underwent a contrast-enhanced CT angiography and a 30-min PET acquisition in list-mode on each PET consecutively. Image noise was defined as mean standard deviation of blood pool activity within the left atria. Target-to-background ratio (TBR) and signal-to-noise ratio (SNR) were measured within the whole-vessel tubular three-dimensional volumes of interest on the cardiac motion and attenuation-corrected F-NaF PET images using dedicated software.

RESULTS

There were significant differences in image noise and background activity between the two PETs (Image noise (%), PMT: 7.6 ± 3.7 vs SiPM: 4.0 ± 2.3, P < 0.001; background activity, PMT: 1.4 ± 0.4 vs SiPM: 1.0 ± 0.3, P < 0.001). Similarly, the SNR and TBR were significantly higher in vessels scanned with the SiPM PET (SNR, PMT: 16.3 ± 11.5 vs SiPM: 32.7 ± 29.8, P < 0.001; TBR, PMT: 0.8 ± 0.4 vs SiPM: 1.1 ± 0.6, P < 0.001). SiPM PET image reconstruction with a 256 matrix, 1.4 mm pixel, and 2 mm Gaussian filter provided best trade off in terms of maximal SNR, TBR, and clinically practical file size.

CONCLUSIONS

In F-NaF coronary PET imaging, the SiPM PET showed superior image contrast and less image noise compared with PMT PET.