Lecture 1 - Therapeutics of ENT

Question 1

Describe the physiology of the ear.

Answer 1

The ear is divided into three parts; outer, middle and inner. The outer ear is air filled. The middle ear is air filled and it consist of the tympanic membrane and a chain of bones; malleus, incus and stapes. The inner ear is fluid filled and consist of three semicircular canals and the cochlea.

Sound waves is directed into the auditory canal by the outer ear and the sound waves is amplified by the tympanic membrane. Then the sound waves is converted into pressure waves in fluid in inner ear (cochlea)
The cochlea consists of 3 ducts; scala vestibuli, scala tympani and scala media. The organ of the corti is found in between the scala media and scala tympani. It has inner and outer hair cells which are sites of auditory transduction. The body of the hair cells are in contact with the auditory nerve fibres, and the cillia of the hair cells is in contact with the tectorial membrane.
The vibrations of the basement membrane activate the inner and outer hairs to cause bending of cilia hairs.

Question 2

What is the purpose of the vestibular system?

Answer 2

The vestibular system is used to maintain equilibrium or balance by detecting angular and linear acceleration of the head. The angular rotation is detected by the semicircular canals and the linear acceleration is detected by the otolithic organs.

Question 3

Describe the hair cell body?

Answer 3

Each hair cell has 50 to 70 small cilia called sterecilia and one big cilium called the kinocilium.

When the stereocilia bend towards the kinocilium, the ion channels opens causing the membrane to depolarise and activate the nerve fibre

When the stereocilia ben backwards to the kinocilium, the ion channel closes, causing the hyperpolarisation of the membrane and inhibition of the auditory nerve fibre.

Question 4

What is Otitis externa?

Answer 4

It is the inflammation of the outer ear canal which is caused by bacteria of fungus. The reason having water in the ear canal, skin of the ear gets damaged or the skin conditions in the ear.

Question 5

What is the treatment for acute Otitis externa?

Answer 5

1. Thorough cleaning of the ear with a anti-inflammatory drops corticosteroid ear drops, anti-infective chloramphenicol ear drops with and astringent aluminium acetate.
2. Anti-infective (antibiotics): topical antibiotics with glucocorticosteroid

Question 6

What is the treatment for chronic otitis externa?

Answer 6

Oral flucloxacillin or clarithromycin
IV cephalosporin if patient is unwell
Antifungal agent: polysorbate, nystatin.

Question 7

Define ototoxicity.

Answer 7

Ototoxicity means toxic to the ear, specifically to the cochlea or auditory nerve and sometimes the vestibular system.

Question 8

What is otitis media?

Answer 8

It is an inflammatory disease caused by by bacterial or fungal infection. Many infections also caused by viruses.

Question 9

What is the treatment for acute otitis media?

Answer 9

1. Local cleansing might help.

2. Systemic antibiotics is used (amoxicillin or clarithromycin)

Question 10

What is labyrinthitis?

Answer 10

It is defined as inner ear dizziness associated with vertigo, balance disorder and tinnitus in addition to hearing loss. It is usually cause by bacteria or viruses but also from stress/ototoxicity.

Question 11

What is the available treatment for labyrinthitis?

Answer 11

Antibacterial agents such as amoxicillin, clarithromycin or IV cephalosporin.
Antiviral agents such as valacyclovir

To treat vertigo and nausea; prochlorperazine

For the anxiety; benzodiazepines
For depression; SSRIs

Vestibular rehabilitation therapy

Question 12

Give some examples of ototoxic drugs

Answer 12

Analgesic and antipyretic - salicylates, quinine
Antibiotics - Gentamicin, neomycin, vancomycin, erythromycin
Antineoplastics - cisplatin
Loop diuretics - furosemide

Question 13

Define rhinitis

Answer 13

allergic acute or chronic inflammation of the nasal mucosa. (Hay fever)

Question 14

Define rhinorrhea

Answer 14

It is the excessive production of watery nasal secretions by the nasal mucosa.

Question 15

List the treatment options for rhinitis and rhinorrhea

Answer 15

1. Nasal blood flow - sympathomimetic agent (ephedrine) vasoconstrictor
2. Anti-inflammatory - glucocorticoids (Beclomethasone)
3. Suppression of mediator release - Cromolyn sodium or omalizumab; inhibit histamine release, prevents lgE interaction
4. Mediator receptor blockade - H1 receptor antagonist;block vasodilation, Leukotriene antagonists;block inflammation.

Question 16

What is the treatment for nasal staphylococci?

Answer 16

Mupirocin ointment can be used to eradicate nasal carriage of MRSA.

Question 17

What causes oral ulceration and inflammation and list the treatment.

Answer 17

Ulceration of the oral mucosa can be caused by trauma, infection, carcinoma, nutritional deficiencies, gastro intestinal diseases and drug therapy.
The treatments available are: Benzydamine (NSAID oromucosal spray), Choline salicylate gel (Mild oral and perioral lesions), carmellose gelatin paste (mechanical protection)
Inflammation treated by corticosteroid (hydrocortisone and betamethasone)

Question 18

How to treat oropharyngeal fungal infections?

Answer 18

Usually caused by candida species, Thrush can be treated with nystatin, miconazole or fluconazole.
Severe invasive candidiasis can be treated with amphoteracin.

Question 19

How to treat oropharyngeal viral infections?

Answer 19

Usually caused by herpes simplex virus.
Primary herpetic gingivostomatitis; analgesics as required with benzydamine and chlorhexidine mouthwash.
Herpetic stomatits; systemic antiviral aciclovir
Herpes simplex: aciclovir or valaciclovir