Since there is no definitive test for nasal valve collapse diagnosis relies on a careful examination along with a thorough understanding of the normal anatomy of the nasal valve. The external nose should be examined and palpated to ascertain the position and caliber of the underlying nasal bones, upper lateral cartilages (ULC), lower lateral cartilages (LLC), and septum. If the external nose is twisted or crooked, one would expect to find deviation of the nasal septum and often associated collapse of the INV. The nasal sidewall should follow a gentle curve from the brow to the nasal tip. For some patients this line is narrowed in the middle vault creating an hourglass shape (Figure 1) suggesting INV narrowing. The ENV is best assessed from the base view and has an overall triangular shape with straight nostril margins. A scalloped shape nasal base (Figure 2) or nostril margins that collapse during gentle inspiration (Figure 3) points to weakness of the ENV.

The Cottle maneuver involves manually elevating the medial cheek to open the nasal valves while inquiring about a subjective improvement in breathing. Although this test can suggest nasal valve collapse false positive results are common. The modified Cottle maneuver is much more specific for nasal valve collapse. This test assesses subjective breathing improvement while supporting the nasal valves with a small instrument, such as a cerumen curette, placed inside the nose. With this test both the INV and ENV can be independently tested to determine the main site of obstruction. It is important not to exaggerate the nasal patency produced and only support the valve as much as could be achieved surgically, but if a significant improvement in breathing is noted, there is a high likelihood of improvement with surgical intervention. ²

Collapse of the ENV is often due to weakness of the alar sidewall. The nasal ala consists primarily of fibrofatty soft tissue without native cartilage to provide support. In some patients the LLC are malpositioned in a more cephalic direction than normal and provide even less support for the ala and the ENV (Figure 4) This can also produce a widened or bulbous nasal tip with scalloping along the alar margins creating an "isolated tip" appearance. Surgical repair involves freeing up the lateral crura from both the vestibular skin and soft tissue attachments and repositioning the cartilage in a more caudal position under the alar groove. The cartilage is then supported by lateral crural strut grafts commonly made from septal cartilage that sit deep to the lateral crural cartilage and rest in a pocket over the pyriform aperture. ³

Alternatively, if the lateral crura are in a normal position, the sidewall can be supported with a batten graft placed superficial to the lateral crura that also rest over the pyriform aperture. This graft can easily be placed through an endonasal approach or as part of an open rhinoplasty. It is critical that the batten graft spans from a lateral point of stability over the pyriform bone to a medial point of stability over the LLC.