Flagging Septum: New Concept to Describe Septal Support Loss and Its Impact on the Nasal Cycle

Summary: The nasal cycle is a physiological phenomenon characterized by alternating congestion and decongestion of the turbinates and the nasal septum, which modulates airflow resistance, promotes humidification, and conditions inspired air. During the congestive phase, contact between the inferior turbinate and the septum may occur, which has been considered part of normal physiology. However, septal surgery involving excessive cartilage resection can alter this relationship, generating a flaccid and unstable septum incapable of serving as an opposing surface. This condition leads to paradoxical symptoms of obstruction, turbulence, and dryness, resembling empty nose syndrome. Clinical observations have repeatedly identified this finding, although it still lacks a clear designation. We propose the term “flagging septum” to graphically describe the loss of central support, in which the septum behaves like a flag fluttering without resistance upon turbinate contact. The literature supports the relevance of septum–turbinate interaction: Keuning described intermittent contact during the cycle; Shaikh demonstrated the clinical association between intermittent septum–turbinate contact and headache; and computational fluid dynamics studies confirmed that the loss of septal opposition alters mucosal stimulation and airflow perception. Furthermore, the role of the nasal septal swell body has been reported as an additional regulator, which loses effectiveness in the absence of rigid septal support. Flagging septum exists and is clinically identifiable; what remains is to quantify its magnitude using objective tools. Adoption of this term may enrich clinical practice and surgical teaching while raising awareness of a preventable complication associated with excessive septal resection.