Clinical Utility of Attenuation Correction with X-Rays in Myocardial Perfusion Spect Studies

Objective. We have compared the uncorrected images of SPECT myocardial perfusion plus gated data with corrected images with X-rays in the management of coronary artery disease.Methods. In 60 patients (p) a stress/rest-gated myocardial perfusion SPECT was performed with attenuation correction with a hybrid gammacamera. All patients underwent cardiac catheterization. 3 types of images were qualitatively evaluated: uncorrected stress/rest (NC), uncorrected stress/rest plus gated (NCG) and stress/rest corrected for attenuation with scatter correction (AC). McNemar's test was used to analyze the statistical differences in assessing the diagnostic accuracy of each type of images; p < 0.05 was considered statistically significant.Results. Fourteen p did not have significant lesions in the coronary arteries (NSL), 46 p showed lesions in coronary arteries: 29 in anterior descending, 26 in right coronary and 18 in circumflex. In right coronary territory, diagnostic accuracy was significantly higher on AC than on NC images (p < 0.001) and on AC than on NCG images (p < 0.01). In NSL group there are significant differences between NC and AC (p < 0.02) and between NCG and AC (p < 0.05).Conclusions. Attenuation correction with X-rays significantly improves diagnostic accuracy of uncorrected images and uncorrected images plus gated.