Nasal septum: The dividing wall within the nose. The nasal septum runs down the middle of the nose creating two sides to the nose, each containing a passageway that ends in a nare (nostril).
The nasal septum is not as simple a structure as it may seem. It consists of (in technical terms) the septal cartilage, the vomer, the perpendicular plate of the ethmoid bone, the maxillary crest and the premaxilla.
Deviation or dislocation of the nasal septum may be present at birth or occur subsequently from trauma. The major problem this causes is airway obstruction. Correction is by surgery.
Septal hematoma is an accumulation of blood within the nasal septum. It is usually due to trauma. Treatment is incision (to drain the blood from the hematoma), packing of the nose (to keep the blood from reaccumulating) and antibiotics, if infected.
Perforation of the nasal septum (a hole through it) can be due to trauma (a blow to the nose, picking the nose, etc), drug abuse (e.g., cocaine), an abscess, and some diseases (e.g., Wegner granulomatosis). Symptoms include crusting, bleeding, discharge and, most dramatically, whistling on inspiration (on breathing in). Treatment is surgical closure of the perforation (a procedure that frequently fails) or the insertion of a specially designed septal button.