The nasal septum is median in location and separates the interior of the nose into left and right nasal cavities. Various diseases can affect the function of the nasal septum, with deviated septum (curvature of the nasal septum) being one of the most common disorders.
What is the nasal septum?
The nasal septum (septum nasi or nasal septum) is the median (middle), continuous partition between the right and left nasal cavities (cavum nasi). The cartilaginous and bony segments of the nasal septum, together with the bony nasal bone (os nasale) forming the upper portion of the bridge of the nose (dorsum nasi), form the nasal framework (also called the nasal pyramid) that gives the external nose its shape.
Anatomy and structure
The nasal septum is located in the guiding groove of the paired maxilla (upper jaw) and is composed of a membranous segment (pars membranacea) and a cartilaginous (cartilago septi nasi or septal cartilage) and a bony portion. The bony portion of the nasal septum can be divided into an upper segment associated with the ethmoid bone, called the lamina perpendicularis ossis ethmoidalis, and a lower segment, the ploughshare bone or vomer. The caudal portion of the nasal septum is mobile, which is why it is called the septum mobile nasi. In addition, a fine vascular plexus, the so-called locus Kiesselbachi, is located in the anterior section of the nasal septum, which is responsible for the blood supply to the nasal septum. At the junction between the ploughshare bone and the nasal cartilage, the nasal septum is thickened, which can cause impaired nasal breathing, especially in adults.
Functions and tasks
The nasal septum serves primarily as the median boundary and partition of the nose and, together with the laterally located nasal walls and the turbinates (choncha nasalis), forms the paired nasal cavities and the curves of the nostrils (nares). This anatomical structure ensures optimal air circulation and passage of airflow through the nares into the nasal vestibule, then through the right and left main nasal cavities and the posterior nasal openings (choanae) into the pharynx (throat) and finally into the lower airways. In addition, the nasal septum stabilizes the nasal framework or pyramid, preventing collapse of the cartilaginous structures. In addition, the olfactory epithelium is located on the upper turbinate and, opposite it, on the nasal septum. This epithelium consists of receptor cells that project into the mucosa (mucous membrane) and pass basally into the nerve processes. Accordingly, this component of the nasal septum, which belongs to the olfactory system, is critically involved in the perception of odors or in the functioning of the sense of smell.
Diseases and ailments
One of the most common impairments of the nasal septum is the so-called septal deviation (deviation of the nasal septum), which can be genetic, growth-related or caused by injuries to the nose (trauma). A more pronounced deviation of the nasal septum is usually associated with impaired nasal breathing and an increased tendency to epistaxis (nosebleeds), sinusitis (inflammation of the sinuses), tubal catarrh (inflammation of the mucous membrane of the ear trumpet), pharyngitis (inflammation of the mucous membrane of the throat) and tonsillitis (inflammation of the tonsils). If there is marked impairment of nasal breathing and/or more severe symptoms as a result of the deviated septum, surgical straightening of the asymmetric cartilaginous and bony portions (septoplasty, submucosal septum resection) to surgically relocate the deviated portions of the septum may be indicated. In some cases, parallel surgery of the external nose (septoplasty) or reconstruction of the paranasal sinuses is indicated. In addition, the superficial vascular network (locus Kiesselbachi) located in the anterior nasal septum can be injured comparatively quickly by “nose picking” or vigorous blowing, so that epistaxis can occur here. Injuries resulting from fractures or foreign bodies can also affect the Locus Kiesselbachi. Rendu-Osler-Weber disease (hereditary hemorrhagic telangiectasia) may also manifest in the anterior region of this nasal segment.As a result of external injury, cocaine abuse, Wegener’s disease, syphilis, or, in rare cases, submucosal nasal resection, a septal perforation (hole or tear in the nasal septum) may manifest as crusting, foetor, epstaxis, and/or whistling breath sounds and, in larger defects, may be closed surgically with a graft. In many cases, however, the cause of a septal perforation cannot be determined. A fracture of the nasal bone can also lead to a septal hematoma, a hemorrhage in the nasal septum, which can lead to swelling with impaired nasal breathing and, if left untreated or infectious, to a septal abscess. If the nasal septum, especially the cartilaginous portion, is levered out of its bony guide groove in the maxilla by a blow, a subluxation is present that can also be eliminated by septoplasty.
