Cloverleaf skull is a rare malformation syndrome in which the head has a cloverleaf aspect. It is caused by the premature closure of several sutures and is apparent from birth. Only 120 cases only have been reported so far, with more cases reported in girls than in boys. In severe forms, bilateral bulging of the skull in temporal regions and on the top induce a downward displacement of the ears, which face the shoulders. Exophthalmos is linked to shallowness of the orbits and the eyelids may fail to close, leading to corneal ulceration. Several other dysmorphic signs have been described: hypertelorism, flattened nose root and mid-face hypoplasia. Venous distension of the scleras and scalp has been noted. Hydrocephalus is often associated, sometimes because of obstruction of the cerebral aqueduct. Malformations of the brain and cerebellum have also often been described. Cloverleaf skull may be observed as an isolated condition or together with other anomalies making up various syndromes known to have different causes: Crouzon disease, Pfeiffer syndrome, Carpenter syndrome, campomelic dwarfism, type II thanatophoric dwarfism, Jeune asphyxiating thoracic dystrophy and amniotic rupture sequence. Early death has been noted in most cases. In exceptional cases of survival, motor retardation is associated with increased intra-cranial pressure that necessitates a ventriculo-peritoneal shunt.
Last update: April 2005