Deviated Nasal Septum - Causes, Types, Clinical Features & Treatment

Deviated Nasal Septum (DNS)

Definition of Deviated Nasal Septum

Deviated Nasal Septum (DNS) is a condition in which the nasal septum deviates from the midline, resulting in unequal division of the nasal cavity.

Normally, the septum divides the nasal cavity into two approximately equal chambers.

In DNS, one nasal cavity becomes narrower at the expense of the opposite side.

• DNS can occur at any age.
• More common in males.
• Most common cause of nasal obstruction.
• Mild septal deviations are common in the general population.

Etiology of Deviated Nasal Septum

1- Trauma (Most Important Cause)

Trauma is the commonest cause of DNS.

What effects are seen as a result of lateral blow to nose VS Frontal Crushing Injury?

Birth Trauma can occur due to:

• Difficult labor
• Forceps delivery

Compression of the nose during birth may produce septal deformity that becomes apparent later in life.

2- Developmental Errors

The nasal septum develops from the Tectoseptal process which descends to fuse with the developing palate.

Abnormal growth between Palate & Base of skull may result in septal buckling and deviation.

DNS is commonly associated with:

• Cleft lip
• Cleft palate
• Dental abnormalities

3- High Arched Palate

Commonly seen in:

• Chronic mouth breathers
• Children with adenoid hypertrophy

What are the features of Adenoid facies?

How does a high arched palate lead to deviated nasal septum?

4- Nasal Masses

Any expanding intranasal lesion may push the septum toward the opposite side.

Examples:

• Juvenile Nasopharyngeal Angiofibroma
• Rhinosporidiosis
• Inverted Papilloma
• Nasal Polyps

5- Racial Factors

DNS is reported more frequently in Caucasian populations.

6- Hereditary Factors

A familial tendency has been observed in some patients.

Classification of Deviated Nasal Septum

DNS can be classified in three ways:

1. Anatomical Classification
2. Morphological Classification
3. Cottle's Classification

1️⃣ Anatomical Classification

Depending on the structures involved:

1- Cartilaginous DNS

Only septal cartilage involved.

2- Bony DNS

Only bony septum involved.

3- Mixed DNS

Both cartilage and bone are involved.

2️⃣ Morphological Classification

1- C-Shaped Deviation

The septum deviates to one side in a C-shaped manner.

Clinical Significance

• Narrowing of one nasal cavity
• Widening of the opposite side
• Compensatory Turbinate Hypertrophy

Why does Compensatory Turbinate Hypertrophy happen in C shaped DNS?

2- S-Shaped Deviation

Deviation occurs on both sides.

May occur in Vertical plane or Anteroposterior plane.

Produces Bilateral nasal obstruction

3- Caudal (Anterior) Dislocation

The caudal end of the septal cartilage becomes displaced from Maxillary crest & Anterior nasal spine.

What type of nasal obstruction seen in Caudal septal dislocation?

4- Septal Spur

A septal spur is a sharp shelf-like bony projection arising from the osteocartilaginous junction of the nasal septum and projecting laterally into the nasal cavity.

What is the most common site of septal spur?

What symptoms can be seen due to septal spur?

5- Septal Thickening

May occur due to:

• Organized septal hematoma
• Overriding fractured septal fragments

3️⃣ Cottle's Classification

1- Simple DNS

• Mild deviation
• No nasal obstruction
• No treatment required

2- Obstructed DNS

• Severe deviation
• May touch lateral wall
• However, after vasoconstrictor application - Turbinates shrink

Treatment

• Medical therapy
• Decongestants
• Sometimes surgery

3- Impacted DNS

• Marked septal angulation
• Spur present
• Septum in contact with lateral wall
• No improvement after vasoconstrictor application.

Treatment

Surgical correction required

Clinical Features of Deviated Nasal Septum

Clinical features can be divided into:

• Symptoms
• Signs

Symptoms of Deviated Nasal Septum

1- Nasal Obstruction

⭐ Most common symptom of Deviated Nasal Septum

The obstruction may be:

• Unilateral
• Bilateral

depending upon the type of septal deviation.

What are the causes of Bilateral nasal obstruction in a case of Deviated Nasal septum?

What is Paradoxical Nasal Obstruction? Why Does It Occur?

2- Headache

Headache may occur due to the following reasons:

• A septal spur may press against the lateral wall and middle turbinate leading to Sluder's Neuralgia.

• Sinusitis

• Vacuum Headache

What is Sluder's Neuralgia? Which nerve gets compressed here? What are the symptoms of Sluder's Neuralgia?

What is the pathophysiology behind sinusitis in Deviated Nasal Septum ?

What is Vacuum headache?

3- Sinusitis

Deviated Nasal Septum may obstruct sinus ostia.

This causes Poor drainage & Poor ventilation leading to recurrent rhinosinusitis.

4- Epistaxis

Occurs due to two mechanisms:

• Septal Spur

• Dry Air Currents - The convex side of the septum is exposed to excessive drying.

This causes crusting, mucosal injury and recurrent bleeding.

How does septal spur cause Epistaxis?

5- Smell Disturbances

Severe Deviated Nasal Septum may prevent inspired air from reaching the olfactory region leading to hyposmia and anosmia.

What is Hyposmia?

what is Anosmia?

6- External Nasal Deformity

Deviated Nasal Septum may be associated with:

• Deviated nasal dorsum
• Tip deformity
• Columellar deviation

due to involvement of cartilaginous and bony framework.

7- Middle Ear Infection

Deviated Nasal SeptumS may contribute to:

• Eustachian tube dysfunction
• Poor middle ear ventilation

predisposing to Recurrent Otitis Media

Signs of Deviated Nasal Septum

1- External Examination

Look for:

• Deviation of external nose
• Dorsal deformity
• Tip deformity
• Columellar deviation

2- Anterior Rhinoscopy

1. Look for Septal Abnormalities

• C-shaped deviation
• S-shaped deviation
• Caudal dislocation
• Septal spur
• Septal thickening

1. Check for Compensatory hypertrophy on opposite side

2. Look for congestion, crusting and dryness in Nasal Mucosa

3. Nasal Discharge

What does presence of nasal discharge in a case of Deviated nasal septum indicate?

3- Re-examination After Vasoconstrictor

Important to differentiate:

• Obstructed DNS
• Impacted DNS

Improvement after vasoconstrictor suggests turbinate contribution to obstruction.

4- Functional Tests of Nose

Cold Spatula Test - Reduced fogging on affected side

Cotton Wool Test - Reduced movement of cotton on affected side

What is Cottle's test? What does a positive Cottle's test indicate?

Investigations of Deviated Nasal Septum

Most cases require no special investigations.

1- X-ray PNS

Previously used for evaluation of associated sinusitis.

2- CT Scan of PNS

Current investigation of choice when:

• Rhinosinusitis is suspected
• Surgery is planned

What are the things seen in CT PNS in a case of Deviated Nasal Septum?

Treatment of Deviated Nasal Septum

Asymptomatic Deviated Nasal Septum

• No treatment required

Many individuals have mild septal deviations without symptoms.

What are the Indications for treatment in a case of Deviated Nasal Septum ?

Symptomatic Deviated Nasal Septum - Surgical Treatment

Two surgical procedures are described:

1- Submucous Resection (SMR)

• Bilateral mucoperichondrial flap elevation
• Extensive removal of septal cartilage

Status ❌ Largely obsolete

Why is SMR not preferred nowadays?

• Radical procedure
• Removes excessive septal support

2- Septoplasty (Treatment of Choice)

⭐ Current gold standard surgery for Deviated Nasal Septum

• Conservative surgery
• Removes only deviated portions
• Preserves septal support

What are the advantages of Septoplasty over SMR?

What are the differences between SMR and Septoplasty?

Complications of Untreated Deviated Nasal Septum

• Habitual Mouth Breathing
• Chronic Rhinosinusitis
• Atrophic Rhinitis
• Asthma

🧠 Viva Pearls

• Most common cause of DNS → Trauma
• Most common symptom of DNS → Nasal obstruction
• Most common cause of nasal obstruction → DNS
• Septal spur arises from osteocartilaginous junction
• Common site of septal spur → Junction of vomer and septal cartilage
• High-arched palate predisposes to DNS
• DNS is commonly associated with adenoid facies
• Impacted DNS requires surgical treatment
• DNS is the most common cause of nasal obstruction.
• Nasal obstruction is the most common presenting symptom.
• Bilateral obstruction occurs in S-shaped DNS and C-shaped DNS with compensatory turbinate hypertrophy.
• Septal spur may cause Sluder's neuralgia.
• Obstruction of osteomeatal complex predisposes to sinusitis.
• Cottle's test evaluates nasal valve obstruction.
• CT PNS is preferred before surgery.
• Septoplasty is the treatment of choice.
• SMR is largely obsolete.
• Untreated DNS may lead to chronic rhinosinusitis, mouth breathing and atrophic rhinitis.