Radiographic Diagnosis of Choanal Atresia Induced Prenatally with Triamcinolone in the Baboon ( Papio cynocephalus)

Abstract

Choanal atresia was diagnosed radiographically using a water soluble contrast media in 2 of 7 Papio cynocephalus exposed to triamcinolone acetonide in utero. In one P. cynocephalus, the atresia was complete and was associated with other orofacial abnormalities. The other animal, previously considered to be normal, had a partial nasal obstruction. The radiographic appearance of the drug-induced defects observed in the baboon closely resemble the descriptions of spontaneously occurring defects in human infants.

Imaging Diagnosis—choanal Atresia in a Dog

“…It results in restricted or absent airflow from the caudal nasal passage to the nasopharynx. It has been diagnosed in humans, 3,5 nonhuman primates, 6,7 sheep, 8 llamas, 9,10 alpacas, 2,4 horses, 11,12 and the dog 13 . Affected neonates may have difficulty while suckling, fail to thrive, develop aspiration pneumonia, or die acutely 2 .…”

“…Clinical signs are most pronounced with bilateral choanal atresia and in obligate nasal breathers such as the horse 12 and humans during the first 2–6 months of life 3 . The diagnosis may be made using CT, MR imaging, positive contrast rhinography, and/or endoscopy 2,3,5,7,12 …”

Bilateral choanal atresia in a cat

“…2 Unilateral atresia has also been reported in dogs, 3 humans, 4–7 camelids, 8 horses, 9 sheep, 10 and baboons. 11 Clinical signs were nasal discharge (uni- or bilateral), stertor, open mouth breathing, and small stature. 2–4 Choanal atresia should be considered in a young animal with chronic upper respiratory signs or as a cause of neonatal death, particularly if signs of upper airway obstruction are noted.…”