Cottle's test tests the patency of the nares in:
Cottle test: It is used to test nasal obstruction due to abnormality of nasal valve as in case of deted nasal septum. in this test, cheek is drawn laterally while the patient breathes quietly. If the nasal airway improves on the test side, the test is positive, and indicates abnormality of the vestibular component of nasal valve.
Atrophic rhinitis
Rhinosporidiosis
Deted nasal septum
Hyperophied inferior turbinate