Another epidemiological report in 2010 found even higher associations between increased incidents of choanal atresia and exposure to second-hand-smoke, coffee consumption, high maternal zinc and B-12 intake and exposure to anti-infective urinary tract medications. The anti-thyroid medication methimazole has been associated with the development of choanal atresia in rare cases if given during the first trimester of pregnancy. Mechanism
Choanal atresia causes closure of the posterior choanae in the nasal cavity. Around 30% of these affect just the bone, while around 70% affect both bone and membranes. Bones affected can include the body of the sphenoid bone, the vomer, the medial pterygoid process of the sphenoid bone, and the horizontal plate of the palatine bone. Diagnosis
Nasal catheter
Choanal atresia can be suspected if it is impossible to insert a nasal catheter. The length of catheter that can be inserted indicates where choanal atresia has occurred: shorter distances indicate a problem with the vomer, while longer distances indicate a problem with the posterior choanae. Mucus can be cleared (using suction) to visualise the abnormality. Radiology
Diagnosis is confirmed using CT scan. This is also useful for differential diagnosis. Treatment
Airway management
As bilateral choanal atresia is an emergency, the airway is secured. A small tube may be placed to the laryngopharynx. Tracheal intubation can also be used. If surgery cannot be performed soon after birth, tracheostomy may have better outcomes. Surgery
Surgery may be used to reopen the airway, particularly with bilateral choanal atresia. This may be approaches through the nasal cavity or through the palate (accessed through the mouth).
In 1979, capreomycin was used in the area of antituberculosis by inhibiting the growth of mycobacterium tuberculosis. References
External links
"Capreomycin". Drug Information Portal. U.S. National Library of Medicine.