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A New Endoscopic Surgical Method for Unilateral Choanal Atresia

INTRODUCTION Choanal atresia (CA) is a rare congenital disorder with one case for every 8000 live births, with a 50% probability of being present with polyhydramnios. Most authors have reported a slight prevalence of CA in female patients. The atresia can be unilateral (41%) or bilateral (59%), total or partial (with various degrees of stenosis, either bony [90%] or membranous [10%]). The atretic plate is most often situated at the posterior end of the septum. At times, the bony atresia can be thick, but it is always the thinnest at the meeting point of the nasal base and the posterior edge of the septum. Choanal atresia is frequently accompanied by other congenital disorders (41%–72% of the cases). Bilateral CA often accompanies the general developmental disorders of the central maxillofacial structures. It has been described as being present in craniofacial dysmorphism (Down, Treacher Collins, and Apert syndromes), orofacial digital syndromes, and Crouzon’s disease. In cases of bilateral CA, other disorders are somewhat more frequent (75% of the cases). International literature has termed the collective group of disorders often accompanying CA (0%–30%) as CHARGE (coloboma, heart defect, atresia of the choana, retarded growth or development, genital hypoplasia, and ear anomalies or deafness), because of the initial letters of the anomalies involved. The joint, embryonic source of these disorders is thought to be probable. Patients with at least four of the major symptoms of CHARGE are categorized to be in this group. The methods used in the management of choanal atresia to date are as follows: removal of the closing plate, perforation of the closing plate, removal of posterior edge of the nasal septum, posterior perforation of the nasal septum, and combinations of the above mentioned methods. The essence of our method is not only the removal of the closing plate, but also, the creation of a new, additional airway canal from the epipharynx, the sphenoid, the posterior ethmoid cells, and the nasal cavity. Our technique can be used only in unilateral cases in which the atretic plate is suitably thin and the developmental status of the sphenoid sinus and the ethmoid cells is adequate. To prove this fact, preoperative computed tomography (CT) scans are essential. Although this stage is usually reached at approximately 5 to 7 years of age, it is not the patient’s age but the developmental stage of the cavity system that is decisive. The physical examination is important in the diagnosis of CA but not decisive in the judgment of developmental status of the paranasal sinuses and the choanal and epipharyngeal spaces.