Comparison of myocardial perfusion imaging using thallium-201 between a new cadmium-zinc-telluride cardiac camera and a conventional SPECT camera.

PURPOSE OF THE REPORT

Cadmium zinc telluride (CZT) solid-state detectors have been recently introduced in myocardial perfusion imaging. However, they had not been yet validated with thallium-201. This study compares the clinical performances of the CZT ultrafast camera GE DNM 530c with a conventional SPECT camera (CC) using thallium-201.

MATERIALS AND METHODS

We prospectively studied with thallium-201 a total of 153 consecutive patients referred for myocardial perfusion imaging at exercise (3-4 mCi) then redistribution (with 1 mCi reinjection). Sequential acquisitions were performed first with a conventional dual-head tomographic Anger camera (CC) in 10 to 15 minutes and then with a CZT camera (CZT) in 5 minutes, in prone position.

RESULTS

In all, 9 patients were excluded: 1 for mispositioning, 3 for camera failure, 3 for delayed acquisition after exercise, 1 for nonacceptance of redistribution, 1 for motion. Acquisition was more comfortable with CZT for all patients. Global counts rate was higher with CZT than with CC (3.6±0.57 KCts/s vs. 1.14±0.16). CZT has a 5-fold increased myocardial counts rate compared with CC (448±69 Kcts in 5 minutes vs. 209±40 Kcts in 12.5±1.8 minutes). Quality of CZT images was considered as better in 40%, equal in 56%, and worse in 4% of cases; we found less artifacts with CZT; diagnostic conclusions were the same in 140 of 144 cases (97%); discordances were 2 artifacts with CC and 2 small ischemia (less than 2 segments) missed by CZT.

CONCLUSIONS

This new dedicated cardiac CZT camera allows with thallium-201 five minutes acquisitions with an increased image quality and a reliable diagnosis quality.