Cerebellotrigeminal and focal dermal dysplasia: a newly recognized neurocutaneous syndrome.

A female child with brachycephaly, hypertelorism, convergent strabismus, interstitial keratitis, analgesia on both sides of the face, absent corneal reflexes, and focal congenital alopecia of a zone of the occipital and posterior parietal scalp is presented. The patient also had generalized hypotonia in early life, and at age 4 years 9 months, she was found to be moderately mentally subnormal and to have severe cerebellar deficit consisting of gait and truncal ataxia. There was no clinical evidence of other cranial nerves being affected. It is postulated that the patient has a cerebellotrigeminal and focal dermal dysplasia due to a development arrest of the ectoderm, which gives rise to the alar plate of the rhombencephalon, the overlying epidermis, the motor nucleus of V, and the trigeminal placodes.