Choanal atresia is a congenital disorder where the back of the nasal passage â€“choana- is blocked, usually by abnormal bony or soft tissue formed during fetal development.
The condition occurs in 1 out of every 5000-6000 live births. Approximately 70% of reported cases are unilateral. Bilateral choanal atresia is commonly associated with other congenital anomalies, such as heart defects, retarded growth, genitourinary abnormalities, and ear anomalies.
Unilateral PCA lesions may go undiagnosed until the child presents with persistent unilateral nasal drainage.
and Failure to pass a 5-6 F catheter through the nasal cavity more than 5.5 cm from the alar rim, but catheter may curl without passing into the nasopharynx.
and The lack of movement of a thin wisp of cotton under the nostrils while the mouth is closed
and The absence of fog on a mirror when it is placed under the nostrils
and Administering into the nose a saline solution which will stay there.
and The ENT doctor can visualize the choanal closure with a small, flexible scope passed through the nostril
CT scanning is the radiographic procedure of choice in the evaluation of choanal atresia. For good results, careful suctioning is performed to clear excess mucus, and a topical decongestant is applied. The purpose of CT scanning is outlined as follows:
and Confirm the diagnosis of choanal atresia (unilateral or bilateral).
and Exclude other possible nasal sites of obstruction.
and Determine the degree of bony, membranous, or mixed atresia.
and Delineate abnormalities in the nasal cavity and nasopharynx.
A few children have signs of respiratory distress at birth which is more obvious while suckling. Also they can develop obstructive sleep apnea during infancy.
Bilateral choanal atresia requires airway support immediately after birth.
In severe cases, longer term airway support with a tracheotomy may be needed until definitive repair can be performed safely.
In cases where the skull base has a relatively normal shape and there are no cardiac contraindications to general anesthesia, bilateral choanal atresia should be repaired shortly after birth.
Timing recommendations for repair of unilateral atresia vary in the literature. Repair at around 2 to 3 years of age is generally accepted.
Surgical procedures to correct choanal atresia can be broadly classified into transnasal and transpalatal approaches. The decision to use a transnasal versus a transpalatal approach rests on the surgeon’s assessment of the choanal anatomy. The composition of the atretic plate, the depth and shape of the nasopharynx, and the presence of other anomalies are the most important factors.
The transnasal approach requires less operative time and causes slightly less morbidity related to the incision. The transpalatal approach provides better exposure and more accurate bone removal. The palatal incision increases operative time and blood loss. The transpalatal approach probably reduces the risk of major vascular injury, intracranial complications, and restenosis.
The use of the rigid endoscope in the management of posterior choanal atresia represents a significant advancement in choanal surgery. It provides an extremely sharp image with a magnified overview. It enables the surgeon to see the tips of his instruments, so that the bone is removed safely under direct endoscopic vision. It allows assessment of the size of the opening, in comparison to the normal choana. It ensures greater precision in flap preservation. The technique is short in time and safe, with early recovery and short hospitalization.