USER-DEFINABLE BULLS-EYE DATABASE ANALYSIS

Several quantitative bull's-eye database programs have been developed and employed successfully, but generally they restrict the user to lim ited types of quantitative analysis. We developed a type of bull's-eye analysis which facilitates user-defined processing, and then explored the effects of various types of processing on the comparisons of pati ent information with that of reference databases. Male and female bull 's-eye database were generated from 32 normal patients using unweighte d 2D prefiltering, ramp backprojection, unweighted 3D postfiltering, a nd peak value circumferential plotting (base method). The data from ea ch patient were then reprocessed and compared to the databases by mean s of three different approaches: (1) using the base method, (2) using average as opposed to peak value profiles, and (3) using a resolution recovery prefilter instead of a smoothing prefilter. Significant diffe rences in the number of apparently abnormal regions were found between the three methods. In other words, the type of single-photon emission tomography (SPET) processing affected the accuracy of comparisons bet ween patient and database information. Because even sophisticared anal ysis can now be performed on personal computers, we conclude that, rat her than a preprocessed data file, clinical ''normal reference'' infor mation should consist of original SPET data (in a standard format, e.g ., Interfile) from a series of documented normal patients. Each user c ould then generate reference bull's-eye database by applying his or he r own clinical processing procedures to the data.