117: Direct comparison of stress Thallium-201/Rest Technetium-99m dual isotope perfusion imaging with Cadmium-Zinc-Telluride detector versus standard dual detector camera

Abstract

Recent advances in nuclear myocardial perfusion imaging (MPI) have provided opportunity for improved image information with an important reduction of exam time and radiation. This technology can be used to explore novel protocols (dual isotope high-speed MPI). Today, two devices exist: D-SPECT and Discovery NM 530c (DNM) camera. With D-SPECT, it was showed that rapid stress Tl-201/rest Tc-99m protocol for use with high-speed MPI has offered the superior qualities of Tl-201 for stress imaging and of the Tc-99m agents for rest imaging can be preserved. However, no study has evaluated the same dual-isotope protocol with the other system. A total of 38 consecutive patients underwent simultaneous dual-radionuclide (stress thallium-201/rest technetium-99m) perfusion imaging with a DNM camera and standard dual dectector camera (S-SPECT) during the month of May 2011. All patients successfully underwent stress/rest MPI with both cameras. In 38 patients (50%) pharmacological stress was induced with dipyridamole. DNM SPECT SSS and SRS correlated linearly with conventional S-SPECT respective scores (r=0.84, p<0.0001 for SSS, and r=0.94, p<0.0001 for SRS). On Bland-Altman analysis there was good agreement between the two imaging methods with a shift for both SSS and SRS (mean difference = 1, 95% confidence interval = −3.74 – 5.74 for SSS; mean difference = −3.0, 95% confidence interval = −3.13 – 3.91 for SRS). The analyze revealed a perfusion defect in both the S-SPECT and DNM scans but systematically perfusionnels defects or scars were more extensive with the DNM-camera. Overall image quality was good to excellent. Our study showed a clinical agreement of 96% between the DNM camera and S-SPECT MPI. The effective dose was 11.9 mSv for the study protocol, with 9.7 mSv coming from the Tl-201. The DNM camera such as D-SPECT camera provides clinical information equivalent to conventional standard SPECT MPI.