An unusual case of Marcus Gunn phenomenon]

The author gives a short review on the course of the disease and the typical symptoms of regular Marcus Gunn phenomenon i.e. the retraction of an usually ptotic lid when the patient opens his mouth or moves his jaw to the healthy side of his face. He then reports on a boy now aged 3 and a half that had suffered from Marcus Gunn phenomenon since his birth, although the disease almost disappeared in the first years of his life. Only a short time before the parents noticed again the phenomenon, occurring now in a modified version; the retraction of the lid appears mainly then when the child pulls himself up from a lying position or raises the arm of this side where the ptosis is located.