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Arrhinia is the absence of the nose at birth. Human nose in profile You may be looking for Nose, a town in Japan, or The Nose, a story by Nikolai Gogol and an opera by Dmitri Shostakovich. ...
Arrhinia is congenital absence of the nose. It is an extremely rare clinical entity: about 20 cases have been reported in total in the literature, and the prevalence at birth is probably less than 1 in 100,000. Even rarer are cases of unilateral arrhinia (congenital absence of half of the nose). Complete arrhinia with a flat and firm area on palpation, normal upper lip and alveolus without cleft palate has been reported in a few cases. In some of the other cases the nose is rudimentary, in the form of blind ending external bump with soft tissue nubbing or blind oval pits. In one case, clinical evaluation also revealed unilateral iris coloboma. High-arched palate, hypoplasia of the auditory canal and mastoid and facial bones, along with the absence of olfactory bulbs and tracts were observed in another case. Extreme expression of Treacher Collins syndrome was reported in an infant with arrhinia, anotia, absent zygomatic bones, hypoplastic mandibular rami, and bilateral coloboma of the iris, choroid, and optic nerves. The Treacher Collins phenotype was mildly expressed in the mother and moderately in the sister. Another case was reported with partial arrhinia and unilateral absence of the orbit with clinical anophthalmos in an otherwise normal child. The CT scan showed inferior continuation of the metopic suture, a hypoplastic nasal chamber filled with soft tissue, a thick bony choanal plate and anterior bony stenosis with defects in the cribriform plate and planum sphenoidale communicating with the soft tissues of the nasal cavity. The nose develops between the 3rd and 10th week of intrauterine life. Failure of the development of nasal placodes, premature fusion of the medial nasal process, lack of resorption of nasal epithelial plugs, and abnormal migration of neural crest cells are the proposed mechanisms that lead to congenital absence of nose. The aetiology is unknown. Most cases of congenital absence of nose are reported to be sporadic and affected individuals have a normal karyotype. In two cases, chromosome 9 anomalies have been reported, and a third child had a de novo reciprocal translocation between chromosomes 3q13.2 and 12p11.2. Gene(s) located on either of the abnormal chromosomes may be involved in the pathogenesis of arrhinia. Antenatal diagnosis of total arrhinia has been described in one report. This diagnosis was confirmed after delivery. Sonographic views of the fetal profile, showing an absence of the nose, led to consideration of the diagnosis. The associated anomalies often have a significant impact on the immediate and long-term outcome of the neonate. There are two challenges in front of an affected newborn: respiratory distress may necessitate emergency management, and there is controversy concerning the choice of technique and timing of procedures. Parental counseling is thus vital and a multidisciplinary team approach is required to optimise the neonatal outcome
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