The disease is mainly characterized by nasal obstruction during inhalation, with both unilateral and bilateral forms.

bubble_chart Etiology

The nasal valve area, also known as the internal nasal orifice, is located deep in the nasal vestibule, anterior to the front end of the inferior turbinate. It is primarily composed of the anteroinferior end of the nasal septal cartilage and the anterior end of the lateral nasal cartilage, forming the base of the pear-shaped aperture at the very front of the nasal cavity. This area is a narrow, triangular structure with an average area of 55–64 (mm)². At the apex of this triangular region, there is a slit-like opening. This incision is narrow, with a normal angle of 10°–15°, and is the narrowest passage in the nasal cavity, referred to as the nasal valve. The resistance to inhaled air is greatest at this point. If the angle of the nasal valve area becomes less than 10° due to congenital malformations, trauma, facial nerve paralysis, or loss of tension in the dilator naris muscle connected to the greater alar cartilage, nasal obstruction occurs.

bubble_chart Clinical Manifestations

The main symptom is nasal obstruction during inhalation, and anterior rhinoscopy reveals no abnormalities such as turbinate hypertrophy or polyps. When the patient's nasal tip is lifted upward, the nasal obstruction immediately disappears. If the thumb and index finger are used to push the lateral sides of the ala outward, the nasal obstruction is also immediately relieved, which is referred to as a positive Cottle's sign.

bubble_chart Diagnosis

The diagnosis can be made using the elevated nasal tip test and a positive Cottle sign. Nasal speculum examination of the anterior nasal septum and major alar cartilage can determine whether there is inward protrusion, thereby identifying the site of obstruction.

The main treatment is surgery. If there is a deviation of the anterior and lower part of the nasal septum, the incision should be made as far forward as possible during the resection of the nasal septal mucoperiosteum to completely remove the deviated cartilage and the underlying ridge. If the lateral nasal cartilage protrudes inward, the nasal tip should be elevated with a small retractor under local anesthesia to expose the lateral nasal cartilage. The overlying skin is incised with a small knife, the subcutaneous tissue is separated, and the mucoperiosteum is incised to expose both sides of the cartilage. The protruding part of the cartilage is then excised, but excessive removal should be avoided to prevent asymmetry in the appearance of both nasal wings. Finally, the skin incision is sutured.