79 Internal or External Nasal Deformity Nasal obstruction is one of the most common complaints encountered by an otolaryngologist/facial plastic surgeon. Nasal obstruction is a symptom, not a diagnosis, and is therefore caused by numerous medical and structural conditions. Airflow within the nasal cavity is both laminar and turbulent. Laminar airflow causes air to reach from the nose to the lower respiratory tract during inspiration. Turbulent airflow facilitates exchange of heat and moisture. The most common medical cause of nasal obstruction is chronic mucosal inflammation/chronic sinusitis, whereas common structural causes include deformities of the external and/or internal nasal valve. When evaluating a patient with nasal obstruction, a detailed history and physical including examination of the nasal septum, inferior turbinate, and internal/external nasal valves is necessary to properly diagnose and treat the underlying condition. Mucosal inflammation can decrease the cross-sectional area of the nasal valve, therefore causing nasal obstruction. This is typically intermittent or fluctuating but can be fixed (see Chapters 27 and 28). Common causes include the following: Structural causes usually cause fixed obstruction. However, patients can have both structural and mucosal causes of obstruction, causing some level of fluctuation even when there is a fixed structural problem. A common area of structural nasal obstruction is the nasal valve. Anatomically, the nasal valve is defined by the septum medially, the nasal floor and inferior turbinate head inferiorly, and the internal nasal valve superiorly. Structural nasal obstruction can be divided into static and dynamic dysfunction. Static dysfunction includes decreased nasal airflow at rest and is usually caused by a deviated septum, inferior turbinate hypertrophy, or narrowed internal nasal valve. Dynamic dysfunction is obstruction that varies with respiratory effort and is related to weakened structural support of the lateral nasal wall. Common structural causes include static dysfunction, dynamic dysfunction, and external factors.
Internal
Mucosal and Soft Tissue Etiologies
Inflammatory rhinosinusitis
Allergic rhinitis
Nonallergic rhinitis
Rhinitis medicamentosa
Nasal polyposis: Usually fixed, but size and symptoms can fluctuate.
Sinonasal neoplasm (see Chapter 30)
Structural Etiologies
Static Dysfunction
Deviated septum: The nasal septum is composed of the quadrangular cartilage anteriorly, the bony vomer inferiorly, and the perpendicular plate of the ethmoid posteriorly. The floor of the septum is composed of the bony maxillary crest. Deviation of either the cartilaginous or the bony septum can contribute to nasal obstruction.
Inferior turbinate hypertrophy: An enlarged anterior portion of the inferior turbinate can narrow the nasal valve and cause symptomatic obstruction.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
