As seen in a typical cleft lip, a cleft of the lip is found in the region of the cupid's bow. The nostril is cleft through the alar dome and extends above onto the nasal dorsum. It passes medial to a normal, but dys- topic, medial canthus. There is an alveolar cleft between the central and lateral incisors that extends above through the pyriform margin lateral to the anterior nasal spine; the nasal septum is not involved. The bony cleft extends through the nasal bone or between the junction of the nasal bone and frontal process of the maxilla. Above the cleft lip, the clefting of the alar dome is associated with deviation to the opposite side of the shortened and broadened columella and nasal tip. Extension of the soft tissue cleft onto the nasal dorsum can be manifest as a series of
vertical soft tissue furrows and ridges.
Vertical inner canthal dysto- pia and severe telecanthus mark the superior aspect of the Number 1 facial cleft. A cranial soft tissue extension characterized by a tongue-like projection of the frontal hairline delineates the number
13 cleft. Skeletal clefting of the maxilla may extend posteriorly to form a complete cleft of the hard and soft palate. The maxilla is hypoplastic in all three dimensions. There is a keel-shaped alveolus and anterior open bite. Normal septation is preserved between the nasal cavity and the hypoplastic maxillary antrum on the affected side. Distortion of the nasal skeleton produces gross flattening of the nasal dorsum. There is asymmetry of the pterygoid plates, of the greater and lesser wings of the sphenoid, and of the floor of the anterior cranial fossa. The distortion of the cranial base may result in a mild plagiocephaly. [from
HPO]