choana


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choana

(ˈkəʊənə)
n
a nasal opening situated towards the back of the nasal cavity in vertebrates
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Both nares were flushed with gentamicin (0.03 mg/mL) and amphotericin B (0.03 mg/mL) diluted in sterile saline, and yellow, mucoid material was recovered through the choana. The toucan was discharged to its owners with recommendations for continued nebulization at home.
A computed tomography (CT) scan face and neck revealed an inhomogenously enhancing soft tissue density lesion measuring 5.7*3.3*3.9 cm involving left maxillary sinus extending to left ethmoid sinus, left nasal cavity reaching up to posterior choana abutting the nasal septum (Figure 1).
It is bordered at the many serious structures like cavernous sinus laterally, the eithmoidal air cells, anterior cranial fossa and optic nerve anteriorly, the clivus posteriorly, the hypophysis fossa and planum sphenoidale superiorly, choana inferiorly, internal carotid artery medially (Mamatha et al.; Seddinghi et al., 2014; Sevinc et al.; Farimaz et al., 2018).
Nasoendoscopy revealed a smooth-surfaced, highly vascular mass occupying the whole nasopharynx, completely obstructing right posterior nasal choana [Figure 2a], and 90% of the left posterior nasal choana [Figure 2b].
The retronasal route, however, requires a retrograde direction starting from the oral cavity, continuing through the nasopharynx and choana and ending at the olfactory mucosa (6).
A choanal polyp (CP) is a solitary benign tissue mass usually originating from the nasal cavity and the paranasal sinuses and extending toward the choana. These polyps may extend into the nasopharynx or even may become sufficiently large to hang down into the oropharynx.
It usually affects the nasal septum first, followed by the anterior segment of inferior turbinates, paranasal sinuses, choana, nasopharynx, orbit, and cranial cavity, not necessarily in that order (7).
Computed tomography (CT) and magnetic resonance imaging (MRI) scanning of the nose were performed, which revealed a left nasal mass lesion arising from the roof of the nasal cavity with extension into the posterior choana (Figure 1).
After the tip of the tube had been passed from the end of inferior turbinate to choana, the tube was rotated into the normal position for passing through the pharynx.
For nasopharyngeal sampling, we inserted a swab into the nostril past the choana and touched the wall of the nasopharynx.
Digital palpation of the nasopharynx was performed just before curettageto assess adenoid site, size, and degree of choanal occlusion, and then just after removal to determine whether there were any remnants and assess the opening of the posterior choana.