You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > PEDIATRIC OTOLARYNGOLOGY Choanal AtresiaArticle Last Updated: Feb 23, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 6
  Author: Ted L Tewfik, MD, FRCS(C), Professor, Department of Otolaryngology, Director of Continuing Medical Education of Otolaryngology, McGill University Medical School; Director, Director of Professional Affairs of Otolaryngology, Department of Otolaryngology, Montreal Children's Hospital; Senior Staff, Montreal General Hospital and Royal Victoria Hospital Ted L Tewfik is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Society of Pediatric Otolaryngology, Canadian Medical Association, Canadian Society of Otolaryngology-Head & Neck Surgery, Quebec Medical Association, and Royal College of Physicians and Surgeons of Canada Coauthor(s): Abdulrahman A Hagr, MBBS, Staff Physician, Department of Otolaryngology, McGill University, Canada Editors: Russell A Faust, MD, PhD, Consulting Staff, Department of Otolaryngology, Columbus Children's Hospital; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Gregory C Allen, MD, Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: complete nasal obstruction in a newborn, congenital choanal atresia, choanae, unilateral atresia, bilateral choanal atresia, posterior nares, definitive choanae, respiratory distress, atresia of choanae, choanal atresia Complete nasal obstruction in a newborn may cause death from asphyxia. During attempted inspiration, the tongue is pulled to the palate, and obstruction of the oral airway results. Vigorous respiratory efforts produce marked chest retraction. Increased cyanosis and death may occur if appropriate treatments are not available; however, if the infant cries and takes a breath through the mouth, the airway obstruction is momentarily relieved. Then the crying stops, the mouth closes, and the cycle of obstruction is repeated. History of the ProcedureIn 1755, Roederer first described congenital choanal atresia; therefore, this condition has been recognized for more than 200 years. In 1854, Emmert reported the first successful surgical procedure for congenital choanal atresia in a 7-year-old boy using a curved trocar transnasally. Over the years, the necessity of serial dilatations to maintain patency of the choanae has been clearly recognized. FrequencyThe average rate of choanal atresia is 0.82 cases per 10,000 individuals. Unilateral atresia occurs more frequently on the right side. The ratio of unilateral to bilateral cases is 2:1. A slightly increased risk exists in twins. Maternal age or parity does not increase the frequency of occurrence. Chromosomal anomalies are found in 6% of infants with choanal atresia. Five percent of patients have monogenic syndromes or conditions. Race: Choanal atresia occurs with equal frequency in people of all races. Sex: More studies report significantly more females than males affected. EtiologyThe nasal cavities extend posteriorly during development under the influence of the posteriorly directed fusion of the palatal processes. Thinning of the membrane occurs, which separates the nasal cavities from the oral cavity. By the 38th day of development, the 2-layer membrane consisting of nasal and oral epithelia ruptures and forms the choanae (posterior nares). Failure of this rupture results in choanal atresia. Although these choanae are not in the same location as the definitive choanae, which are eventually located more posteriorly, the unexpectedly anterior extent of choanal atresia is explained. PathophysiologyA number of theories have been proposed to explain the occurrence of choanal atresia, and they can be summarized as follows:
ClinicalThe clinical evaluation includes a complete physical examination to assess for other congenital anomalies. A small feeding tube could be used to determine the patency of the choana, but a complete nasal and nasopharyngeal examination should be performed using a flexible fiberoptic endoscope to assess the deformity. A simple method using the automatic tympanometer to screen newborns for congenital choanal atresia was recently published. The sensitivity and specificity of the technique in diagnosing a patent nostril was reported as 100 per cent. However, a high level of suspicion is required to diagnose bilateral choanal atresia. Many patients have an associated narrowed nasopharynx, widened vomer, medialized lateral nasal wall, and/or arched hard palate. Associated malformations occur in 47% of infants without chromosome anomalies. Nonrandom association of malformations can be demonstrated using the CHARGE association, which appears to be overused in clinical practice. The components of the CHARGE association are as follows:
The percentages of the different anomalies in CHARGE association are as follows:
Differential diagnosis Deviated nasal septum Dislocated nasal septum Septal hematoma Mucosal swelling Turbinate hypertrophy Encephalocele Nasal dermoid Hamartoma Chordoma Teratoma Imaging Studies
Diagnostic Procedures
Surgical therapyTreatment can be divided into emergent and elective definitive categories. Bilateral choanal atresia in a neonate is an emergency that is best initially treated by inserting an oral airway to break the seal formed by the tongue against the palate. This oral airway can be well tolerated for several weeks. The method of repair is controversial, with no technique having gained universal acceptance. Bilateral choanal atresia in the newborn requires prompt diagnosis and airway stabilization. An oral airway, McGovern nipple, and intubation are viable options. The ideal procedure for choanal atresia restores the normal nasal passage, prevents damage to growing structures important in facial development, is technically safe, requires short operative time, and provides short hospitalization and convalescence. Procedures Transnasal puncture, with or without a microscope, became unpopular because of the high rate of failure that then required revision. This was attributed to the difficulty in visualizing the choanal area that required special surgical attention, such as the vomerine septal bridge and bony narrowing of the lateral walls. The transnasal approach becomes more difficult in the presence of septal deviation, turbinate hypertrophy, nasal discharge, and elongation of the depth from the nasal vestibule to the posterior choanae as patients grow. The transseptal technique consists of making a window in the septum anterior to the atretic plate. Transpalatal repair is a technique that provides excellent exposure and has a high success rate but requires more operative time. The increased blood loss, possible occurrence of palatal fistula, palatal dysfunction, and maxillofacial growth disturbance are complications of this procedure (see Image 3). The endoscopic technique (nasal or retropalatal), with or without powered instrumentation, offers excellent visualization with great ease in removing the bony choanae. Microdebriders will continue to advance the field of endoscopic surgery, providing clearer operative fields and causing less tissue trauma for experienced surgeons. However, the severity of complications, including the potential for rapidly aspirating orbital and cerebral contents when laminae are violated, must be appreciated and respected. Carbon dioxide and potassium titanyl phosphate (KTP) lasers are easy and quick and create minimal discomfort to the patient. The time of hospitalization is short, and the operation can be repeated if a good result is not initially achieved. Most importantly, a stent is not usually needed. Postoperative detailsInfants with documented gastroesophageal reflux disease (GERD) require prolonged stenting and dilatations for choanal restenosis and removal of granulation tissue. Stenting is usually performed using an endotracheal tube or Foley catheter. The advantages of Foley catheter stenting for choanal atresia are as follows:
The use of stents in the treatment of patients with choanal atresia is a controversial subject. Some surgeons believe that stents are useful in stabilizing the nasal airway in the postoperative period to prevent the development of stenosis by maintaining a lumen. However, others believe that stents may act as a nidus for infection and may induce a foreign body reaction. This may contribute to choanal restenosis, much as an endotracheal tube may cause subglottic stenosis. Therefore, the use of stents following repair of choanal atresia requires the use of prophylactic antibiotic and antireflux medications. Cedin et al (2006) analyzed the long-term results of a new stentless surgical technique for choanal atresia. They reported that, using neither stents or nasal packing, this technique allowed fast recovery in a one-step surgery. Follow-upFollowing surgical repair of choanal atresia, patients may require operative debridement or periodic dilatations. Periodic dilations can sometimes be performed as an outpatient procedure with local decongestant and topical anesthesia using urethral sounds.
Article Last Updated: Feb 23, 2007 | ||||||||||||||||||||||||||
