Choanal atresia: histochemical, immunohistochemical and ultrastructure study of the nasal mucosa.

Objectives: To study the nasal mucosal changes in cases with choanal atresia at the light and electron microscope and to compare the results with the normal side in unilateral cases.

Study Design: Cross sectional study.

Setting: Tertiary University hospital, departments of Otolaryngology and pathology.