ARHINIA (ABSENT NOSE)

Total arhinia is defined as the complete absence of the soft tissues of the nose with or without associated abnormalities. The intracranial contents are usually normal, in contradistinction to holoprosencephaly in which a rudimentary nose or proboscis is present. In total arhinia the entire nose and olfactory bulbs are absent.

In partial arhinia, at least one nostril and olfactory nerve is present

EMBRYOLOGY

• Failure of development of the frontonasal prominence results in complete or partial nasal aplasia.
• Arhinia in the holoprosencephalic sequence is part of a complex spectrum of midfacial anomalies that are thought to arise from a primitive defect of the prechordal mesenchyme (tissue that is responsible for the induction of facial and cerebral structures).

ULTRASOUND

• Unilateral (small pit seen in area of nostril) or bilateral.
• On sagittal views the concavity extending from the forehead to the upper lip is present in the position normally occupied by the nose.

ASSOCIATED SYNDROMES

• Isolated.
• Part of a malformation complex:
• Holoprosencephaly.
• Treacher-Collins syndrome.

Hypoplastic nose in holoprosencephalic sequence

• Hypoplastic nose.
• Cleft lip.
• Bilateral anophthalmos.
• Low folded ear.
• Hypotelorism.

REFERENCES

1. Meyer R. Total external and internal construction in arhinia. Plast Reconstr Surg 1997;99:534-542.

2. Cole R, Myer C, Bratcher G. Congenital absence of the nose: a case report. Int J Pediatr Otorhinolarynol 1989;17:171-177.

3. Cohen D, Goitein KJ. Arhinia revisited. Rhinology 1987;25:237-244.

4. Cusick W, Sullivan CA, Rojas B, Poole AE, Poole DA. Prenatal diagnosis of total arhinia. Ultrasound Obstet Gynecol 2000;15:259-261.