Pathology of the Larynx

Question 1

What is the cardinal symptom of laryngeal disease?

Answer 1

Hoarseness of voice

Question 2

What are the benign causes of voice hoarseness?

Answer 2

Infection
Inflammation
Vocal cord nodules

Question 3

What must always be done when someone presents with hoarseness of voice?

Answer 3

Presence must be regarded as an ominous sign requiring careful investigations

Question 4

Why must the presence of hoarseness be considered as an ominous sign?

Answer 4

Given the extent of a serious pathology that can cause hoarseness of loss of voice

Question 5

What are the more concerning pathologies causing hoarseness of voice?

Answer 5

Damage to nerve supplying larynx

Pathology directly involving tissues of larynx

Question 6

What can cause damage to nerves supplying larynx?

Answer 6

Either surgery or disease involving structures close to larynx

Question 7

What determines the effects of damage to nerves supplying the vocal cords?

Answer 7

Degree of damage (complete or partial)

Wether this is unilateral or bilateral

Question 8

What are the potential consequences of damage to nerves supplying the vocal cords?

Answer 8

Phonation

Breathing

Question 9

Give an example of when damage to nerves supplying vocal cords might not be too severe?

Answer 9

Damage to superior laryngeal nerve (or its external branch) may only cause some weakness of phonation, particularly higher pitch

Question 10

What does unilateral complete injury to the recurrent laryngeal nerve cause?

Answer 10

Vocal cord on affected side to become immobile

Question 11

What could cause unilateral complete injury to recurrent laryngeal nerve?

Answer 11

Division of the nerve

Question 12

What position does the vocal cord take up in unilateral complete injury to the recurrent laryngeal nerve?

Answer 12

Neutral (or paramedian) position between abduction and adduction

Question 13

What is the result of the opposite cord being unaffected in unilateral complete injury to the recurrent laryngeal nerve?

Answer 13

It can compensate quite well

Question 14

What are the consequences of unilateral complete injury to the recurrent laryngeal nerve?

Answer 14

May be some hoarseness and a weaker cough

Passage of air through glottis will be minimally affected, if at all - difficulties breathing not usually reported

Question 15

What happens if there is bilateral complete injury to recurrent laryngeal nerves?

Answer 15

Both vocal cords assume paramedial position, and the rima glottidis becomes extremely narrow

Question 16

What is the result of the narrowing of the rima glottidis in bilateral complete injury to recurrent laryngeal nerve?

Answer 16

Affects patients ability to speak
Position of vocal cords obstructs movement of air into and out of trachea, and so patients present with difficulty breathing and sometimes stridor

Question 17

What presents a greater threat, lesions that progressively involve both nerves/only bruise the nerves, or complete division of nerves?

Answer 17

Could be lesions that progressively involve both nerves, or only bruise the nerves

Question 18

Why do lesions that progressively involve both nerves, or only bruise the nerves, present greater threat?

Answer 18

Semon postulated reason may be due to that in partial injury to recurrent laryngeal nerve, the abductor muscles are paralysed before the adductors, therefore in gradual lesions, the vocal cords are adducted together, causing significant obstruction to air moving into and out of trachea.

It has since become apparent that it is much more complex than this

Question 19

What should happen if the two vocal cords significantly impede air flow?

Answer 19

An emergency tracheostomy may be necessary to allow the patient to breath

Question 20

What route does the left recurrent laryngeal nerve take?

Answer 20

It loops around the arch of the aorta before ascending back up in a groove between oesophagus and trachea

Question 21

What is result of the recurrent laryngeal nerves having a long course in the neck?

Answer 21

They are susceptible to disease and injury that affects the neck and upper chest

Question 22

Give two examples of conditions that may affect the left recurrent laryngeal nerve

Answer 22

Aortic arch aneurysms

Left apical lung tumours

Question 23

How may carcinomas of the larynx present?

Answer 23

Hoaseness and/or airway problems

Question 24

What is often the earliest presenting sign of lesions affecting the vocal cords?

Answer 24

Horaseness of voice

Question 25

When is laryngeal cancer prognosis favourable?

Answer 25

If the laryngeal cancer is small and involves glottis, and is caught early

Question 26

Why is laryngeal cancer prognosis favourable when it involves the glottis?

Answer 26

This area has very minimal lymphatic drainage, so less likely to spread

Question 27

Where does laryngeal cancer have a poorer prognosis?

Answer 27

In the supra- and infraglottic regions

Question 28

Why does cancer in the supra- and infraglottic regions have a poorer prognosis?

Answer 28

They drain to neck nodes and paratracheal nodes respectively