Describe the nasal septum with its pathology and surgery.

Structure and Development

• The nasal septum divides the nasal cavity into two halves.
• It is osseocartilaginous, comprising the septal (quadrilateral) cartilage anteriorly, the perpendicular plate of the ethmoid posterosuperiorly and the vomer posteroinferiorly, with the maxillary and palatine crests below.
• It is covered by mucoperichondrium over cartilage and mucoperiosteum over bone.

Septal Pathology and Surgery

• Septal haematoma — blood between cartilage and perichondrium after trauma, presenting with bilateral nasal obstruction and a smooth bulging septum that is soft and fluctuant on palpation
• It must be drained urgently.
• Treatment — incision and drainage under aseptic conditions with quilting sutures or a drain to prevent re-accumulation, nasal packing, and systemic antibiotics
• Septal perforation — causes whistling (with a small perforation), crusting, epistaxis and obstruction (with a large one), from turbulent airflow and drying at its margins
• Its causes must be worked through — previous surgery.
• A perforation with crusting and destruction warrants ANCA and biopsy.
• Treatment — saline douching and emollients for symptoms, which is sufficient for many; a silastic button to occlude it; and surgical repair with flaps and an interposition graft, which is difficult and unreliable for large perforations
• Septoplasty is the modern operation — conservative, preserving as much cartilage and bone as possible and correcting only the deviated portion. It has replaced submucous resection (SMR).
• Septoplasty is avoided before 17 years, since the septum is a growth centre for the midface, and early surgery may disturb facial development
• Complications — haemorrhage; haematoma and abscess; perforation; saddle deformity and columellar retraction; adhesions; persistent obstruction where the nasal valve was the real problem; and anosmia
• Warn the patient that a septoplasty does not correct external deformity, which needs a septorhinoplasty — an expectation mismatch that accounts for much dissatisfaction
• Septal cartilage depends on its perichondrium, exactly as auricular cartilage does.
• Most adults have a deviated septum and most are asymptomatic.
• Obstruction is often felt on the wider side, from compensatory turbinate hypertrophy.
• A caudal dislocation obstructs the valve and causes symptoms out of proportion to its size
• Bleeding comes from the convexity, where the mucosa is stretched, thin and dried by turbulent airflow
• A spur may cause contact-point headache by impinging on the turbinate.
• Palpate a bulging septum after trauma; soft and fluctuant means haematoma and needs drainage today