ENT - The larynx

Question 1

A 55 year old women presents to the GP with a 3 week history of hoarseness. Describe the muscles and nerves controlling movement of the vocal cords.

Answer 1

Vocal cord adduction:

• lateral cricoarytenoids (+ transvere and oblique arytenoids)
• RLN (inferior br.)

Vocal cord abduction:

• posterior cricoarytenoid muscles
• RLN (inferior br.)

Vocal cord tension:

• cricothyroid muscles
• SLN (external br.)

Vocal cord relaxation:

• thyroaretenoid muscles
• RLN (inferior br.)

Question 2

A 55 year old women presents to the GP with a 3 week history of hoarseness. What is your differential diagnosis?

Answer 2

1. Laryngeal tumours - malignant or benign (polyps, papillomas)
2. Vocal cord palsy: idiopathic, iatrogenic, laryngeal cancer, intrathoracic disease (e.g. lung cancer, aortic arch aneurysm)
3. Vocal cord nodule
4. Reinke’s oedema
5. Functional dysphonia
6. Neurological causes
7. GORD

Question 3

A 55 year old women presents to the GP with a 3 week history of hoarseness. What is your initial management?

Answer 3

1. Urgent CXR - if +ve refer to resp.
2. If -ve - refer to ENT for fibreoptic nasoendoscopy.
3. Further Ix directed by clinical picture e.g. TFTs

Question 4

What type of laryngeal carcinoma is most common? Name 2 risk factors.

Answer 4

Squamous cell carcinoma

RFs:

• smoking
• alcohol

Question 5

A 55 year old women presents to the GP with a 3 week history of hoarseness. She is suspected of having laryngeal carcinoma. Which Ix would you request?

Answer 5

1. Panendoscopy (examination of whole aerodigestive tract) + biopsy
2. CT/MRI neck: look for cartilage erosion and lymphadenopathy of deep cervical chain
3. CXR or CT chest

Question 6

How do carcinomas of the glottis, supraglottis and infraglottis differ?

Answer 6

Presentation

• glottis cancer: presents early with hoarseness
• supra-/infraglottis cancer: presents later with non-specific symptoms e.g. cough, throat irritation, referred otalgia, lymphadenopathy

Prognosis

• glottis cancer: very good (95% 5y survival) since small lesions cause symptoms early and lymphatic drainage is poor
• supra-/infraglottis cancer: much poorer as tend to present late and lymphatic drainage allows spread (pre-epiglottis + deep cervical LNs for supraglottis and pre-tracheal + deep cervical for infraglottis)

Question 7

How would a small laryngeal tumour (T1/2) be treated? What are the complications of this?

Answer 7

Radiotherapy - causes painful mucositis towards end of Tx with dysphagia (may need admission for enteral feeding + analgesia)

Question 8

How would a large laryngeal tumour (T4) be treated?

Answer 8

Surgical excision: partial or total laryngectomy.
In total laryngectomy, larynx is removed and trachea is brought to skin as an end-stoma. Pharynx is opened and repaired to reconstitute swallowing mechanism.

Question 9

Suggest 2 mechanisms for voice restoration post-total laryngectomy.

Answer 9

1. Tracheo-oesophageal puncture: 1 way valve created between back wall of trachea + front wall of pharynx/oesophagus.
2. Artifical larynx (Servox)