PT - JOURNAL ARTICLE AU - K. Lance Gould AU - Tinsu Pan AU - Catalin Loghin AU - Nils P. Johnson AU - Stefano Sdringola TI - Reducing Radiation Dose in Rest–Stress Cardiac PET/CT by Single Poststress Cine CT for Attenuation Correction: Quantitative Validation AID - 10.2967/jnumed.107.049163 DP - 2008 May 01 TA - Journal of Nuclear Medicine PG - 738--745 VI - 49 IP - 5 4099 - http://jnm.snmjournals.org/content/49/5/738.short 4100 - http://jnm.snmjournals.org/content/49/5/738.full SO - J Nucl Med2008 May 01; 49 AB - Cardiac PET/CT is optimized by cine CT with dedicated shift software for manual correction of attenuation–emission misregistration. Separate rest and stress CT scans incur greater radiation dose to patients than does standard helical PET/CT or “pure” PET using rotating rod attenuation sources. To reduce radiation dose, we tested quantitative accuracy of using a single poststress cine CT attenuation scan for reconstructing rest perfusion images to eliminate resting CT attenuation scans. Methods: A total of 250 consecutive patients underwent diagnostic rest-dipyridamole myocardial perfusion PET/CT with 82Rb and a 16-slice PET/CT scanner using averaged cine CT attenuation data during breathing at rest and stress. After correcting for any attenuation–emission misregistration, we quantitatively compared resting perfusion images reconstructed using rest cine CT attenuation data with the same resting emission data reconstructed with poststress cine CT attenuation data. Automated software quantifying average regional quadrant activity, severity, size, and combined size and severity of perfusion defects was used for this comparison. Results: Resting perfusion images reconstructed using rest cine CT attenuation data were quantitatively comparable to resting images reconstructed with poststress cine CT attenuation data with no clinically significant differences. Twenty-five (10%) of 250 cases required shifting of stress cine CT attenuation data to achieve optimal attenuation–emission coregistration with resting perfusion data. Eliminating rest CT attenuation scans reduced CT radiation dose by 50% below rest-plus-stress cine CT protocols. Conclusion: Resting perfusion images reconstructed using poststress cine CT attenuation data are quantitatively comparable to resting images reconstructed with resting cine CT attenuation data. Eliminating the rest CT scan reduces CT radiation dose by 50%.