Cataracts Flashcards
What are cataracts?
Opaque protein deposits onto lens
What are the risk factors for cataracts?
↑Age Smoking DM Corticosteroids Female Malnutrition Acute dehydration Inflammatory eye disease
What are the causes of congenital cataracts?
TORCH: Toxoplasmosis Other Rubella CMV HSV
How do cataracts present?
Gradual onset Blurred vision: Difficulty reading/see TV TROUBLE W/NOCTURNAL VISION Dazzle/glare haloes Opacity
What are signs of a cataract in a child
Squint
White pupil
Nystagmus
Amblyopia
How are cataracts investigated?
Fundoscopy
Slit lamp: Red reflex, lens appears brown/white
What are the different types of cataracts?
Nuclear (elderly): Refractive index varies
Cortical: Spoke-like shape, mild acuity affect
Post sub capsular: Clasic glare from sunlight/nocturnally, fast progression
How are cataracts treated?
Conservative: Mydriatic drops
Surgery: Phaecoemulsion + Intra-ocular lens implant
How soon should congenital cataracts be acted upon?
4weeks
What are the indications for cataract surgery?
QoL↓
Unable to read number plate @ 20m
What should be done in pre-op for cataract surgery?
Ocular biometry to measure curvature of cornea & length of eye for lens size
Why are cataracts a big deal?
Leading cause of blindness worldwide
What are complications of cataract surgery?
Anterior uveitis
Retinal detachment
Glaucoma
How do corneal ulcers occur?
Inflammation/infection of cornea
Disruption of epithelial layer
Leads to ulcer formation
What is the function of the cornea?
1) Protects the eye
2) Refracts light
Does the cornea have a blood supply?
No-avascular
How does a corneal ulcer present?
VERY painful eye causes a SQUINT Red eye Tearing & watering Photophobia ↓Visual acuity
How are corneal ulcers investigated?
URGENT referral to ophthalmology
HIV test
Slit lamp w/1% Fluorescein
Why is fluorescein used when studying corneal ulcers?
Differentiate between keratin & dendritic ulcers
How are corneal ulcers treated?
Gram +ve: Chloramphenicol drops
Gram -ve: Ofloxacin
Other: Cefuroxime drops + Gentamicin drops
What are HSV dendritic ulcers?
HSV1 infection
Acute pain, watering & photophobia
Can lead to blindness!
Tx: TOP Aciclovir 3% drops x5/day
What are the Sx of a corneal abrasion?
Red + painful eye Worse on movement Sensation of FB Blurred vision Conjunctival/ciliary injection Epithelial defects on staining
What are Sx of a penetrating corneal injury?
Sudden onset pain after incident
Distorted iris/pupil
Air bubbles under cornea
What actions are risk factors for a penetrating corneal injury?
Welding Grinding Bottled Mowing Hamering
