Validation of CT attenuation correction for high-speed myocardial perfusion imaging using a novel cadmium-zinc-telluride detector technique

The aim of this study was to validate attenuation correction (AC) using low-dose standard CT for myocardial perfusion imaging (MPI) on a novel ultra fast γ-camera with cadmium-zinc-telluride (CZT) detector technology.

Sixty-six patients (body mass index ± SD, 27.2 ± 3.5 kg/m(2); range, 19.1-36.0 kg/m(2)) underwent a 1-d (99m)Tc-tetrofosmin adenosine stress-rest imaging protocol with 15-min acquisitions on a standard dual-head SPECT camera. All scans were repeated within minutes on the CZT camera, with 3-min acquisitions for stress (low dose) and 2-min acquisitions for rest (high dose) as recently established. We compared maximum myocardial uptake (20-segment model) from CZT versus standard SPECT MPI by intraclass correlation without and with CT AC. In addition, clinical agreement for each coronary territory for all scans from both devices was assessed, and Bland-Altmann (BA) limits of agreement for percentage uptake were calculated.

The clinical agreement between CZT and standard SPECT cameras was 96% for noncorrected low- and high-dose images (r = 0.90 and BA = -18 to 15, and r = 0.91 and BA = -15 to 16, respectively), and agreement after AC was 96% for low- and 99% for high-dose images (r = 0.87 and BA = -16 to 14, and r = 0.88 and BA = -16 to 14, respectively).

Our results support that AC of MPI on the novel CZT camera, compared with AC MPI on a conventional SPECT camera, is feasible because it provides a high correlation of segmental tracer uptake and an excellent clinical agreement.