The Red Eye

Question 1

Definition of a pterygium

Answer 1

Wedge-shaped hyperplasia of the conjunctiva

Question 2

What is a pterygium a result of?

Answer 2

Chronic irritation and sun exposure

Question 3

Pathophysiology of the pterygium?

Answer 3

Grows over the limbus onto the cornea

Fine, nearly transparent collagen fibres replaces by thicker, yellowish, more durable fibres and sometimes calcium crystals

Question 4

Management of pterygiums

Answer 4

Lubrication

Anti-inflammatory drops for acute flare-ups

Surgical excision if visual axis affected

Question 5

Definition and presentation of a subconjunctival haemorrhage

Answer 5

Diffuse or localized area of blood under conjunctiva

Usually unilateral, localized, and sharply circumscribed

Underlying sclera not visible

No inflammation, pain or discharge unless associated trauma

Vision unchanged

Question 6

Causes of subconjunctival haemorrhage

Answer 6

idiopathic

trauma

cough

aspirin

hypertension

Question 7

management of subconjunctival haemorrhage

Answer 7

reassure - resolves within 10-14days

check BP, coag studies or INR if indicated

dilated exam if Hx of trauma

Question 8

what to do on examination of a corneal foreign body?

Answer 8

visualise foreign body +/- rust ring under slit lamp

apply fluoroscein to assess for epithelial defect

evert eyelids to check for retained foreign bodies

posterior segment exam if history warrants

Question 9

management of corneal foreign body

Answer 9

remove with needle under slit lamp

remove rust ring with a burr

antibiotic ointment

eye pad

review in 3 days

Question 10

bacterial, viral and fungal causative organisms of infectious corneal ulcer?

Answer 10

bacterial: staph, strep pneumo, pseudomonas, moraxella
viral: herpes simplex
fungal: consider if trauma from vegetation

Question 11

risk factors for infectious corneal ulcers

Answer 11

contact lens wear - especially extended

trauma

ocular surface disease

Question 12

likely Dx for a patient complaining of:

pain

photophobia

blurred vision

mucopurulent/purulent discharge

Answer 12

infectious corneal ulcer

Question 13

signs of infectious corneal ulcer

Answer 13

focal white infiltrate/opacity in corneal stroma

fluoroscein staining defect in overlying epithelium

ciliary injection

anterior chamber inflammatory reaction (cells, flare, keratic precipitates)

hypopyon

Question 14

management of infectious corneal ulcers

Answer 14

corneal scraping, contact lens, and swabs for CULTURE

topical antibiotics based on pathogen and severity

eg. non-contact lens wearers: G chloramphenicol
eg. contact lens wearers: G ofloxacin + cessation of lenswear (suspected pseudomonas)

Question 15

definition of marginal keratitis

Answer 15

immune response to exotoxins released by bacteria colonising the lid margin, commonly staph

Question 16

symptoms of marginal keratitis

Answer 16

irritated red eye

foreign body sensation

Question 17

signs of marginal keratitis

Answer 17

peripheral corneal infiltrates

no epithelial defects

Question 18

management of marginal keratitis

Answer 18

eliminate colonisation - lid hygiene, antibiotic drops

steroid drops for inflammation if required