Investigation of dose reduction in cardiac perfusion SPECT via optimization and choice of the image reconstruction strategy

background:we investigated the extent to which the administered dose (activity) level can be reduced without sacrificing diagnostic accuracy for three reconstruction strategies for spect-myocardial perfusion imaging (mpi). methods:we optimized the parameters of the three reconstruction strategies for perfusion-defect detection over a range of simulated administered dose levels using a set of hybrid studies (derived from 190 subjects) consisting of clinical spect-mpi data modified to contain realistic simulated lesions. the optimized strategies we considered are filtered backprojection (fbp) with no correction for degradations, ordered-subsets expectation-maximization (os-em) with attenuation correction (ac), scatter correction (sc), and resolution correction (rc), and os-em with scatter and resolution correction only. each study was evaluated using a total perfusion deficit (tpd) score computed by the quantitative perfusion spect (qps) software package. we conducted a receiver operating characteristics (roc) study based on the tpd scores for each dose level and reconstruction strategy. results:for fbp, the achieved optimum values of the area under the roc curve (auc) at 100%, 50%, 25%, and 12.5% of standard dose were 0.75, 0.74, 0.72, and 0.70, respectively, compared to 0.81, 0.79, 0.76, and 0.74 for os-em with ac–sc–rc and 0.78, 0.77, 0.74, 0.72 for os-em with sc–rc. conclusion:sour results suggest that studies reconstructed by os-em with ac–sc–rc could possibly be reduced, on average, to 25% of the originally administered dose without causing diagnostic accuracy (auc) to decrease below that of fbp.