The nasal valve refers to the narrowest portion within the nasal cavity.  This typically corresponds to the crease above the nostrils externally.  If this region is compromised for any reason – from trauma, prior surgery, scarring, aging, a congenitally narrow nose or weak cartilages, breathing through the nose can become quite difficult. 

Individuals with incompetent nasal valves may have no significant history of nasal trauma.  On examination, the septum may be straight, but the individual continues to experience difficulty breathing particularly with exertion, increased activities such as exercise.  These people often benefit from breathe right strips.

Despite technological advances in imaging, nasal fractures are still definitively diagnosed by physical examination as most fractures are palpable.  External changes and asymmetries are typically visually discernible.