Cerebro-oculo-nasal syndrome

Fabrice Cuillier, MD.*, J.L. Alessandri, MD.**, F. Cartault, MD.***

*   Department of Gynecology, Félix Guyon Hospital, 97400 Saint-Denis, Ile de la Réunion, France.
**  Department of Neonatology, Felix Guyon Hospital, 97400 Saint-Denis, Réunion, France.
*** Department of Genetics, Felix Guyon Hospital, 97400 Saint-Denis, Réunion, France.

Introduction
Cerebro-oculo-nasal syndrome is a rare multiple congenital anomaly with structural anomalies of the central nervous system, ocular and nasal malformations. It was first described in 1993 by Richieri-Costa and Guion-Almeida. Later Guion-Almeida reported 13 more cases and reviewed seven others. Of this 20 reported cases, 18 were from Brazil.
Main manifestations include mental retardation with various structural anomalies of the central nervous system: encephalocele, ventricular dilatation, abnormalities of the corpus callosum, Dandy-Walker malformation, holoprosencephaly.
The ocular malformations were mainly microphtalmia or anophthalmia.
The nasal malformation resembled proboscis-like nares.
Etiology
The etiology of most of the reported cases remains unknown. Only one of the cases had known PTCH1 mutation (Sonic Hedgehog).
Ultrasound findings
Bilateral anophthalmia
Abnormal nares
Abnormal ears
Central nervous system anomalies
Additional findings:
Brachycephaly
Prominent forehead
Ocular hypertelorism
Malar hypoplasia
Large philtrum
High-arched palate with atypical cleft
Inferior rotated ears with hypoplastic tragus
Holoprosencephaly-like anomalies such as agenesis of the corpus callosum, cystic malformations or frontal encephalocele are present in 50% of the affected pregnancies. Abnormal proboscis-like nose appears to be  unique and diagnostic finding despite the clinical variability among the cases. 
Differential diagnosis

• Fronto-facio-nasal dysplasia

• Acromelic fronto-nasal dysostosis
• Oculo-auriculo-fronto-nasal syndrom
• Amniotic band syndrom

Associated anomalies: Malar hypoplasia; Pedunculated post-axial polydactyly; Genital hypoplasia; Hyperpigmented skin lesions
Prognosis

This syndrome is associated with a severe mental retardation, deafness and blindness and has a very poor prognosis.

Case report