Red eye 2

Question 1

What is keratitis ?

Answer 1

Inflammation and damage of the cornea

Question 2

What are the 2 main types of keratitis ?

Answer 2

Infectious and non-infectious (non is not very common)

Question 3

What are the causes of infectious keratitis ?

Answer 3

• Viral - herpes, adenovirus
• Bacterial - staph A mainly, also sometimes pseudomonas aerginosa
• Fungal
• Acanthamoeba

Question 4

What are the causes of non-infectious keratitis ?

Answer 4

• RA
• Hypersensitivity

Question 5

What is the main complication that often occurs when someone develops keratitis ?

Answer 5

Ulcers - corneal and dendritic

Question 6

What is a major risk factor for the development of keratitis ?

Answer 6

• Contact lens use
• Less commonly due to a scratch on the cornea

Question 7

What are the main organsism associated with contact lens induced keratitis ?

Answer 7

• Pseudomonas aeguinosa

Question 8

What are the symptoms of keratitis/corneal ulcers?

Answer 8

• Pain and redness (around the cornea)
• Foreign body/gritty sensation
• Corneal or dendritc ulcers
• Profuse lacrimnation
• Photophobia
• Hypopyon (inflam cells in the anterior chamber looks white)

Question 9

What causes dendritic ulcers in keratitis ?

Answer 9

Herpes infections

Question 10

Why is it important to distinguish between a herpes infection causing keratitis and an autoimmune cause causing it ?

Answer 10

Because if steroids are given they can cause a corneal melt or perforation of the cornea in herpes infections

Question 11

What is an adenovirus keratitis usually preceded by ?

Answer 11

URTI

Question 12

What is the treatment for bacterial, viral or autoimmune keratitis ?

Answer 12

• Bacterial = ofloxacin
• Viral = aciclovir
• Autoimmune = oral/topical steroids

Question 13

How is the cause of corneal ulcers/keratitis diagnosed ?

Answer 13

Corneal scrap

Question 14

What investigation can be done to identify a corneal ucler/abrasion ?

Answer 14

Fluorescein dye with slit lamp

Question 15

What are the 2 main types of orbital cellulitis ?

Answer 15

• Preseptal
• Orbital

Question 16

What is pre-septal cellulitis ?

Answer 16

• It is an infection of the soft tissues anterior to the orbital septum - this includes the eyelids, skin and subcutaneous tissue of the face, but not the contents of the orbit.
• It is characterised by eyelid erythema and oedema

Question 17

What is orbital cellulitis ?

Answer 17

Inflammation due to infection of the soft tissues (fat and muscles) of the orbit posterior to the orbital septum

Question 18

What are the main risk factors for the development of orbital cellulitis ?

Answer 18

• It is usually caused by a spreading URTI from the sinuses
• Recent eyelid infection/ insect bite on eyelid (Peri-orbital cellulitis)
• Ear or facial infection

Question 19

Are eye movements ok in pre-septal cellulitis ?

Answer 19

Yes

Question 20

What are the signs/symptoms of orbital cellulitis ?

Answer 20

• Oedema and erythema around the eye
• Eyelid oedema and ptosis
• Visual disturbance
• Severe ocular pain & Painful eye movements
• Ophthalmoplegia - cant move the eye
• Proptosis - abnormal protrussion/displacment of the eye
• Fever
• Headache
• N&V in meningeal involvement (rare tho)

Question 21

The features of orbital cellulitis and preseptal cellulitis are very similar, however what features of orbital cellulitis must be absent for it to be preseptal cellulitis ?

Answer 21

Orbital signs (pain on movement of the eye, restriction of eye movements, proptosis, visual disturbance, chemosis, RAPD) must be absent in preseptal cellulitis - their presence would indicate orbital cellulitis

Question 22

What investigations should be done in someone with suspected orbital cellulitis ?

Answer 22

• Bloods - raised inflammatory markers
• Swab of any discharge present
• Contrast CT of the orbit may help to differentiate between preseptal and orbital cellulitis & determine if there is an abscess. It should be performed in all patients suspected to have orbital cellulitis

Question 23

What is the treatment of orbital ceullitis ?

Answer 23

• Cared for by ophthalmology and ENT
• But drain if there is an abscess
• Give - Flucloxacillin + ceftriaxone +/- metronidazole