Ghost 15 - Clear Backup history of deleted backup files

I've used Norton Ghost for many years and in the process of changing out some hard drives, I deleted several backup files with Windows Explorer.  Now I realize that I should have done it through Ghost.  As a result, my backup history shows lots of backups that don't exist.  This includes both drive and file backups.  How can I clear out the backup history of everything except for the backups that really do exist?  Do I need to uninstall Ghost and reinstall it?