Choanal atresia is a rare congenital abnormality occurring with a frequency of 1 in 5000-8000 births. The cause of choanal atresia is heterogenic factors, or the aetiology of this abnormality is multiple. The persistence of the nasobuccal membrane or disturbances of the buccopharyngeal membrane recanalization are the classical basis for choanal atresia. Choanal atresia usually coexists with other congenital abnormalities (1). In 1945 Durword, Lord and Polson described 390 cases of choanal atresia coexisting with other congenital abnormalities. However, these authors maintained that the coexistence of these abnormalities was accidental. In 1981 Pagon suggested the term CHARGE for a definition of abnormalities often connected with each other. The term CHARGE denotes: C – coloboma, H – heart disease, A – atresia choanae, R – retarded growth and development and/or central nervous system anomalies, G – genital hypoplasia, E – ear anomalies and/or deafness (2, 3, 4, 5, 6). Genetic examinations prove that a specific chromosomal aberration is responsible for CHARGE. Very rarely choanal atresia may appear in a family (7). Congenital choanal atresia was described for the first time by Roeder in 1775. The first documented operation for this condition was performed by Emmert in 1861.

Nowadays estimation of nasal patency in the newborn is a part of the routine physical examination after birth. Because an infant before 6 weeks of age does not breathe through its mouth, a bilateral choanal atresia is a severe developmental abnormality which may be the cause of acute respiratory insufficiency. In children with bilateral choanal atresia, protection of the airway patency by intubation or by insertion of an oral pharyngeal tube is an essential activity. Unilateral choanal atresia may go unnoticed in the first weeks of life. Congenital choanal atresia is more common in females than in males. The unilateral variety is usually right sided. Patients with unilateral choanal atresia have symptoms of various degrees of intensity – from severe difficulty in breathing, to cases when patients only cannot blow their nose on one side (8, 9, 10). Usually an obstructed nasal cavity retains a mucous secretion. Bilateral choanal atresia is a cause of severe breathing difficulties in the newborn and requires immediate medical intervention.

The only appropriate treatment of choanal atresia is surgical restoration of choanae patency (11). There are some methods for operative treatment of this abnormality. Operative treatment may be carried out by transnasal, transpalatal, transseptal or transantral approaches (9, 10). Nowadays surgical treatment of choanal atresia usually is carried out by transnasal or transpalatal approaches. The operation consists of forming a permanent junction between the nasal cavity and nasopharynx by surgical removal of a bony obstruction or mucous membrane occlusion in a choanal site. From 4 to 6 weeks after an operation separators are fixed in the choanal site. Separators are usually made from intubation tubes. The newly formed openings have a tendency to secondary narrowing. This situation calls for reoperation many times. A transnasal surgical approach is less traumatic, but gives limited control in the surgical area. A transpalatal approach makes comfortable surgical preparation of the posterior nostrils possible, but is associated with the largest blood loss during operation and with a risk of temporary or permanent palatal dysfunction (11). Sometimes the function of the palate muscles may be incorrect, motions may be lazy, palatal occlusion is insufficient, and contractions may have reduced speed. It has an influence on auditive tube function. The levator of the palatine velum muscle, as the pharyngeal constrictor muscles (apart from the tensor veli palatini muscle), receives motor and sensory branches from the pharyngeal plexus. The pharyngeal plexus consists of the glossopharyngeal nerve, vagus nerve, accessory nerve and sympathetic nerves. The tensor veli palatini muscle is innervated by trigeminal nerve branches which descend from the auricular ganglion. A surgical transpalatal intervention and a lengthy retention of separators in posterior choanae and nasopharynx may cause dysfunction of the Eustachian tube with serous otitis media.

The aim of this work was the estimation of otitis media with effusion occurrence in children under post-operative treatment for choanal atresia, depending on the surgical approach.

In the Department of Paediatric Otorhinolaryngology in Warsaw, in the period 1959-2002, 175 operations for choanal atresia were carried out. A group of 11 children operated on choanal atresia between 1996-2002 was examined (7 boys and 4 girls). The age of the children was between 4 months and 14 years. Acoustic impedance audiometry was performed in all children. The type of tympanometry curve was analysed depending on the applied surgical approach in a choanal atresia operation.

Bilateral choanal atresia was recognised in 4 children (3 boys, 1 girl). In the remaining 7 children unilateral choanal atresia was recognised; in 5 children it was right-sided, and in 2 children it was left-sided. Four children with bilateral choanal atresia had coexisting developmental anomalies, as congenital heart disease, psychomotor development retardation, developmental anomaly of the ribs, dystrophy, anal atresia, hypothyreosis, progressive choroidal atrophy, and decreased muscle tone. In one girl from this group we recognised a bilateral perceptive hearing loss requiring a hearing aid. Among 7 children with unilateral choanal atresia we observed congenital heart disease, psychomotor development retardation, and iris defect of the right eye. In 4 children unilateral choanal atresia was the sole developmental anomaly. Sensorineural hearing loss did not appear in children with unilateral anomaly of choanae. Five children were operated on by transpalatal approach, 7 children by transnasal approach. A tympanometry curve type B was obtained in 4 children – in this group 2 children had a transnasal approach, while in 2 children there was a transpalatal approach. In the remaining 7 children there was a tympanometry curve type A and stapedial reflex was present. In 1 child a stapedial reflex was absent at 4000 Hz.

1. Choanal atresia is a congenital developmental anomaly usually coexisting with other anomalies (CHARGE) or, rarely, as an isolated congenital anomaly.

2. Bilateral choanal atresia coexists more frequently with other anomalies than unilateral choanal atresia.

3. Surgical treatment of choanal atresia and lasting maintenance of separators may give a transient insufficiency of levator palatine velum muscle and auditive tube dysfunction. It may lead to serous otitis media occurrence.

4. Objective examinations of hearing acuity (auditory evoked potentials, acoustic impedance audiometry) should be performed in children with choanal atresia, to detect a congenital hearing loss or otitis media with effusion connected with Eustachian tube dysfunction.

5. In the examined group we did not find a dependence between the type of operative approach in the surgical treatment of choanal atresia and occurrence of serous otitis media.