Effectiveness of Prone Imaging for Spect Myocardial Perfusion According to Gender and Artifact Location

Background:
Performing SPECT myocardial perfusion (MPI) in the prone position with TC⁹⁹M, reduces diaphragmatic artifacts among men. Prone increases the rate of stress only (SO) SPECT MPI, thus significantly reduces radiation. However its efficiency amongst women and for other attenuation artifacts is unknown.

Methods:
The normal SPECT MPI of 131 men and 86 women, with prone images, were analyzed for perfusion defects according to the 17 AHA segments for stress supine/prone and rest images. Artifacts were classified as diaphragmatic (DA), breast (BA), apical (AA), inferolateral (IA) and septal (SA).

Results:
Using prone, low radiation protocol SO was performed in 68/86 (79%) of women compared to 70/131 (53%) in men (p=0.007).

Men had more DA (122/131; 93%) than women (30/86; 35%; p<0.0001) and women had more BA than men (53/86; 61% vs. 1/131; 1%; p<0.0001). AA were present in 19/131 (15%) of men and 14/86 (16%) of woman (p=0.4), IA in 2/131 (2%) of men and 3/86 (3%)of woman (p=0.6) and SA in 2/131 (2%) of man and 0 of women (p=0.3).

DA were corrected by prone imaging in 109/122 (89%) of men and in 29/30 (97%) of woman (p=0.2); BA in 43/53 (81%) of women and 0/1 (0%) of man (p=0.05); AA in 12/19 (63%) of men and in 10/14 (71%) of women (p=0.7); IA in 2/2 (100%) of men and 2/3 (67%) of women (p=1.0) and SA in 2/2 (100%) in men. On a patient basis, prone imaging allowed for total artifact correction in 116/131 (89%) in men as compared to (70/86) 81% in women (p=0.14).

Conclusions:
By correcting most DA, BA and AA in women, prone allowed to perform more SO SPECT MPI with low radiation protocol than in men. Although DA are less frequent than BA, they are even better corrected by prone imaging in women.