[Pourfour du Petit syndrome].

The Pourfour du Petit's syndrome is characterized by the unilateral appearance of mydriasis, lid retraction and exophthalmos. It suggests the existence of a localized oculosympathetic hyperactivity. It tends be to caused by injuries that suppose a stimulus of the sympathetics fibers at level of the proximal portion of the first dorsal root or in the cervical sympathetic chain. We report the clinical case of a young patient who developed a Pourfour du Petit's syndrome secondary to a small condrosarcoma of the proximal portion of the first rib. The observation of this syndrome is exceptional but its knowledge permits, by the great topographic value that possesses, a rapid identification of the causative injury.