Examining fixation behavior by observing the bulbus position (direction of gaze) in patients with macular disease (modified from [8]).
Left: With the gaze directed straight forward, the letter A falls directly on the nonfunctioning macula and thus into the central scotoma. The patient is unable to read.
Right: With eccentric fixation, the letter is fixated with a normal part of the retina (in this example, above the lesion); in the visual field it is now below the scotoma. The gaze is directed upward. When this is combined with a magnifying visual aid, reading is now possible.