Comparison of image quality, myocardial perfusion, and left ventricular function between standard imaging and single-injection ultra-low-dose imaging using a high-efficiency SPECT camera: the MILLISIEVERT study.
UNLABELLED
SPECT myocardial perfusion imaging plays a central role in coronary artery disease diagnosis, but concerns exist regarding its radiation burden. Compared with standard Anger SPECT (A-SPECT) cameras, new high-efficiency (HE) cameras with specialized collimators and solid-state cadmium-zinc-telluride detectors offer potential to maintain image quality (IQ), while reducing administered activity and thus radiation dose to patients. No previous study has compared IQ, interpretation, total perfusion deficit (TPD), or ejection fraction (EF) in patients receiving both ultra-low-dose (ULD) imaging on an HE SPECT camera and standard low-dose (SLD) A-SPECT imaging.


METHODS
We compared ULD HE SPECT with SLD A-SPECT imaging by dividing the rest dose in 101 patients at 3 sites scheduled to undergo clinical A-SPECT myocardial perfusion imaging using a same day rest-stress (99m)Tc protocol. Patients underwent HE SPECT imaging after an initial approximately 130-MBq (3.5 mCi) dose and SLD-A-SPECT imaging after the remainder of the planned dose. Images were scored visually by 2 masked readers for IQ and summed rest score. TPD and EF were assessed quantitatively.


RESULTS
Mean activity was 134 MBq (3.62 mCi) for ULD HE SPECT (effective dose, 1.15 mSv) and 278 MBq (7.50 mCi, 2.39 mSv) for SLD A-SPECT. Overall IQ was superior for ULD HE SPECT (P < 0.0001), with twice as many studies graded excellent quality. Extracardiac activity and overall perfusion assessment were similar. Between-method correlations were high for summed rest score (r = 0.87), TPD (r = 0.91), and EF (r = 0.88).


CONCLUSION
ULD HE SPECT rest imaging correlates highly with SLD A-SPECT. It has improved image quality, comparable extracardiac activity, and achieves radiation dose reduction to 1 mSv for a single injection.
['Einstein|Andrew J|AJ|', 'Blankstein|Ron|R|', 'Andrews|Howard|H|', 'Fish|Mathews|M|', 'Padgett|Richard|R|', 'Hayes|Sean W|SW|', 'Friedman|John D|JD|', 'Qureshi|Mehreen|M|', 'Rakotoarivelo|Harivony|H|', 'Slomka|Piotr|P|', 'Nakazato|Ryo|R|', 'Bokhari|Sabahat|S|', 'Di Carli|Marcello|M|', 'Berman|Daniel S|DS|']
D000328:Adult D000368:Aged D003324:Coronary Artery Disease D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D055414:Myocardial Perfusion Imaging D011446:Prospective Studies D015899:Tomography, Emission-Computed, Single-Photon D016277:Ventricular Function, Left
SPECT radiation dose reduction high-efficiency camera