1. An image examination method comprising: an acquisition step of acquiring a to-be-examined object image obtained by capturing an image of a to-be-examined object; a setting reading step of reading an examination region definition information from a storage device in which the examination region definition information is previously stored; an examination region extracting step of extracting a portion constituting the examination region as an examination region image from the to-be-examined object image based on the examination region definition information; and an examination process step of examining the to-be-examined object by analyzing the examination region image, wherein the examination region definition information is a parameter used as a constraint condition in an optimum solution search process, and wherein, in the examination region extracting step, a position and a shape of the examination region are separately determined in each to-be-examined object by performing an optimum solution search process of obtaining an optimum solution of the examination region in the to-be-examined object image with the parameter as the constraint condition.