On the settings menu, you can specify what you want the viewer to do with localizer images. Some studies, such as CTs, clearly mark which images are localizers and which are slices. Others, including MRIs, do not.
eRAD PACS has the ability to automatically detect images not in the same plane as images in a series, and can mark these as localizer images.
Click Settings/Localizers and click on Auto Find Localizers to automatically identify the localized images. To permanently set this value, click Settings/Customize Settings/Layout and check the Find Localizers setting to enable the find localizer function.