Statistical brain imaging analysis has good objectivity and reproducibility. In Japan, statistical parametric mapping (SPM) and three-dimensional stereotactic surface projections (3D-SSP) are used nationwide as statistical imaging analysis with standard brain coordinates. They often help to interpret brain single photon emission computed tomography (SPECT) images by avoiding possible pitfalls (e.g., effects of aging, atrophy) with which clinicians are unfamiliar. However, this type of analysis presents a problem: statistical processing requires many normal subject images. The easy Z-score imaging system (eZIS) is one of the statistical analysis methods that uses SPM processing in normalization and smoothing, and it has the function of image conversion leading to statistical analysis without a control database. Therefore, statistical analysis can be used in clinical practice by sharing a prepared normal database. By unifying the image quality by processing a shared database, this program has great potential for sharing patient imaging data in many hospitals. It is expected that the eZIS will help perform detailed analysis in many functional diseases in collaborative studies. This article describes the interpretation of brain SPECT images and suggests the usefulness and potential of eZIS.