PBL 9 - Tongue and Mouth Ulcers

Question 1

Draw and label a diagram of the larynx.

Answer 1

See Steward McDonald’s drawing.

Include:

1. Unpaired cartilages: epiglottis, thyroid cartilage, cricoid cartilage
2. Paired cartilages: arytenoids (corniculate, cuneiform)

Question 2

List the 6 cartilages/cartilage pairs in the larynx/

Answer 2

Unpaired:

1. Epiglottis
2. Thyroid cartilage
3. Cricoid cartilage

Paired:

1. Arytenoids
2. Corniculates
3. Cuneiforms

Question 3

Where is the larynx located?

Answer 3

Midline

C4-C6

Question 4

Discuss the functions of the larynx.

Answer 4

1. Valve/sphincter action to close the lower respiratory tract
   a. Closes laryngeal inlet/opens oesophagus during swallowing
2. Production of sound
   a. Changes position/tension of vocal folds
   b. Air passing through larynx makes the vocal cords vibrate - this creates sound
   c. Sound is further modulated by the upper respiratory tract and oral cavity
3. Respiration
   a. Vocal folds open wider during forced inspiration
   b. Larynx shuts the vocal folds when air is retained in the thoracic cavity to stabilise the trunk, e.g.
   - –When lifting heavy objects
   - –Increasing intra-abdominal pressure

Question 5

What is the innervation of the larynx?

Answer 5

1. Superior laryngeal nerves
   a. Branch of vagus nerve
   b. Splits into 2 branches:
   - –External branch (motor for cricothyroid m.)
   - –Internal branch (sensory - laryngeal cavity above vocal folds)
2. Recurrent laryngeal nerves
   a. Motor - all intrinsic laryngeal muscles (except cricothyroid)
   b. Sensory - laryngeal cavity below vocal folds

Question 6

What is the blood supply of the larynx?

Answer 6

1. Superior laryngeal artery
   a. Of superior thyroid artery (of external carotid a.)
2. Inferior laryngeal artery
   a. Of inferior thyroid artery (or thyrocervical trunk of subclavian artery)

Question 7

What is the venous drainage of the larynx?

Answer 7

1. Superior laryngeal veins
   a. Drain into superior thyroid veins (into internal jugular v.)
2. Inferior laryngeal vein
   a. Drain into inferior thyroid veins (into brachiocephalic vein)

Question 8

Describe the histology of the larynx.

Answer 8

Above the vocal folds: non-keratinsed stratified squamous epithelium

Below the vocal folds: pseudostratified ciliated columnar epithelium

Question 9

Describe the mucosal folds of the larynx (including vocal folds).

Answer 9

1. Ventricular folds (superior)
   a. Space between them: rima vestibula
   b. Function: hold breath against thoracic pressure
2. Vocal folds (inferior)
   a. Space between them: rima glottidus
   b. Function: speech

Question 10

Draw a diagram of the extrinsic and intrinsic tongue muscles.

Answer 10

See posters on the wall.

Question 11

Draw a diagram of the gross features of the tongue.

Answer 11

Include:

1. Apex
2. Root of tongue
3. Oral part
4. Pharyngeal part
5. Terminal sulcus
6. Foramen caecum
7. Papillae:
   a. Filiform
   b. Fungiform
   c. Vallate
   d. Foliate

Question 12

What is the blood supply of the tongue?

Answer 12

Lingual artery (external carotid artery)

Question 13

What is the venous drainage of the tongue?

Answer 13

Deep lingual veins
Dorsal lingual veins

Drain into internal jugular vein

Question 14

Describe the innervation of the tongue.

Answer 14

MOTOR:

1. Hypoglossal
2. Vagus nerve (palatoglossus m.)

SPECIAL SENSORY:

1. Facial n. (ant 2/3)
2. Glossopharyngeal (post 1/3)

GENERAL SENSORY:

1. Lingual n. (branch of V3) (ant 2/3)
2. Glossopharyngeal (post 1.3)

Question 15

Draw and label the lymph nodes in the head and neck.

Answer 15

Include:

1. Submental
2. Submandibular
3. Pre-auricular
4. Retro-auricular
5. Occipital
6. Jugulo-digastric node
7. Deep cervical nodes
8. Jugulo-omohyoid node
9. Superficial cervical nodes
10. Supraclavicular nodes

Question 16

Describe the development of oral cancer.

Answer 16

1. Precancerous and benign neoplastic disease
   a. Leukoplakia - “a white patch or plaque (hyperkeratosis) that cannot be scraped off and cannot be characterised clinically or pathologically as any other disease”
   b. Erythroplakia - “red velvety patches of epithelial atrophy and pronounced dysplasia”
2. Squamous cell carcinoma

Question 17

Describe the pathophysiology of oral squamous cell carcinoma, including its progression.

Answer 17

Pathophysiology:

1. Raised nodular lesions with central ulceration and hard raised edges
2. Well differentiated
3. Keratinising

Progression:

1. Normal
2. Hyperplasia/hyperkeratosis
3. Mild/moderate dysplasia
4. Severe dysplasia/carcinoma in situ
5. Squamous cell carcinoma

Question 18

Describe the role of the speech therapist in treating patients after surgery for oral cancer.

Answer 18

1. Assessment of patient:
   a. Swallowing function
   b. Communication
2. Treatment of patient:
   a. Exercises to maintain maximum oral function
   b. Communication therapy
   c. Voice restoration therapy
   d. Advice and support before surgery – outline the expected changes
   e. Arrange for the patient to meet other laryngectomy patients
   f. Inform about patient support groups
   g. Ensure safe transition from tube feeding to oral feeding

Question 19

Describe the lymphatic drainage of the tongue.

Answer 19

ORAL PART:

1. Submental and submandibular lymph nodes
2. These then drain into the deep cervical lymph nodes
   a. NOTE: the tip of the tongue also drains into the jugulo-omohyoid node via the submental nodes
   b. Also drains directly into the deep cervical lymph nodes

PHARYNGEAL PART:
1. Drains directly into the jugulodigastric node of the deep cervical chain