[A new concept of Pierre Robin syndrome and disease: dysneurulation of the rhombencephalon].

Pierre Robin's syndrome, a disorder apparently constituted by peripheral signs, is in fact the result of early major disturbances of ontogenesis of motor and regulatory organization of the fetal rhombencephalon. This is confirmed by the presenting signs in neonates with Pierre Robin's syndrome: --electrophysiological deglutition and sucking disorders as demonstrated on electromyography; --disorders in tone of tongue, pharyngeal and laryngeal muscles; --cardiac and respiratory regulatory disorders as shown by central and obstructive apneas with diminished oxygen pressure and bradycardia of central origin during sleep; and gastro-esophageal reflux. Associated signs indicating that Pierre Robin's syndrome is a separate disease entity are: --evidence of a rhomboencephalic neurocristopathy (malformation of 3rd and 4th aortic arch arteries, thymic and parathyroid hypoplasia) associated with a central rhomboencephalic lesion and resulting in dysneurulation; --mesencephalic lesion as seen in Stickler's syndrome and prosencephalic lesion as in Binder's syndrome, indicating more diffuse cephalic dysneurulation. The common origin of Di George's and Pierre Robin's syndromes is emphasized, the neonatal microretrognathism of the latter syndrome being a bulbar sign. Pierre Robin's syndrome has a poor prognosis, as there is a fatal outcome in one out of four neonates affected, and it appears to be an affection that is the clinical expression of an early major anomaly of cephalic neurulation.