26. Red eye Flashcards
history taking red eye
Sudden onset? Photophobia? Pain? Blurred vision? Pupil size?
Contact lens wearer? Until we know what is going on I would strongly advise you to not wear contact lenses. Do you have glasses you can wear?
red flags red eye
Decreased visual acuity = acute angle closure glaucoma, anterior uveitis
Photophobia = keratitis
Significant pain
examiantion red eye
CN 2,3,4,6 esp visual acuity with snellen chart, pupils and RAPD, pain on movement?
BP, BP, temperature, regional lymph nodes, look for signs of systemic disease/illness
to complete:
- fluorescin
- intraocualr pressure
- opthalmoscopy
serious causes of red eye that you need to rule out
Acute glaucoma
Anterior uveitis
Corneal causes
Corneal ulcer and contact lens-related red eye
Corneal foreign body
Neonatal conjunctivitis
Trauma
Penetrating eye injury
Chemical injuries, particularly alkali solutions
Scleritis
Endophthalmitis
glaucomacute angle closure claucoma presentation
PC: unilateral pain in the eye, red eye, headache, blurring of vision with lights seen surrounded by halos, nausea and vomiting, occurs in evening
what in medical history/drug history should you ask about ?acute angle closure glacuoma
MHx: recent pupil dilation using phenylephrine
DHx: tricyclics (antimuscarinics)
o/e red eye
o/e: reduced visual acuity, tender hard eye, fixed and mid-dilated pupil which is unresponsive to bright light
plan ?acute angle closure glaucoma in priamry care
- Admit immediately for specialist ophthalmology assessment
- If immediate admission is not possible, start emergency treatment in primary care:
- Let the person lie flat with their face up and head not supported by pillows, as this may relieve some of the pressure on the angle.
+ If the drugs are available, give: pilocarpine eye drops, one drop of 2% in blue eyes or 4% in brown eyes; acetazolamide 500 mg orally to reduce production of aqueous humour (provided that there are no contraindications); analgesia; and an anti-emetic, if required.
investigations acute angle closure
tonometry to assess for elevated IOP
gonioscopy (literally looking, oscopy, at the angle, gonio): a special lens for the slit lamp that allows visualisation of the angle
plan ?acute angle closure glacuoma in secondary care - initial and defincitive
initial
1. IV/oral actetazolomide
+ parasympatheicomimetic eg topical pilocarpine
+ beta blockers eg timolol
+ alpha-2 antagonist eg apraclonidine
defintive
1. Laser peripheral iridotomy
= creates a tiny hole in the peripheral iris → aqueous humour flowing to the angle
drug class actezolomide? how does it work
Acetazolamide is a carbonic anhydrase inhibitor which works by reducing the secretion of aqueous humor
how do beta vlockers work for acute angle closure glaucoma
reduce intraocular pressure by decreasing the rate of production of aqueous humor
why does pilocarpine work in acute angle closure glacuoma
Pilocarpine is a topical miotic - pulls iris away from trabecular meshwork to allow improved drainage of aqueous humor
(parasympatheticomimetic)
causes of acute angle closure glaucoma
Age-related changes in the structure of trabecular meshwork
Pupil dilating drops, such as phenylephrine
Systemic antimuscarinic medicines, such as tricyclics, can precipitate acute glaucoma
presentation anterior uveitis. histroy and exam
PC: acute onset pain, blurred vision and photophobia
o/e: small, fixed oval pupil, ciliary flush
visible fluid level in the eye
associated with anterior uveitis and keratitis
hypopyon; describes pus and inflammatory cells in the anterior chamber, often resulting in a visible fluid level
conditions associated with anterior uveitis
ankylosing spondylitis
reactive arthritis
ulcerative colitis, Crohn’s disease
Behcet’s disease
sarcoidosis: bilateral disease may be seen
management anterior uveitis
urgent review by ophthalmology
cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate
steroid eye drops
what is keratitis
inflammation of the cornea
causes of keratitis
viral = hsv
bacterial
- staph aureus
- pseudomonas aergionosa in contact lens wearers
fungal
amoebic
parasitic
features keratitis
red eye: pain and erythema
photophobia
foreign body, gritty sensation
hypopyon may be seen
Normal visual acuity unless ulceration
management of infectious keratitis
refer contact lens wearer for same day assessment
topical antibiotics
typically quinolones are used first-line
cycloplegic for pain relief
e.g. cyclopentolate
complications of keratitis
corneal scarring/corneal ulcer
perforation
endophthalmitis
visual loss
risk factors for corneal ulcer
contact lens use
vitamin A deficiency: a particular problem in the developing world
recent infectious keratitis
features that are seen particualrly in corneal ulcer
eye pain
photophobia
watering of the eye
management of ?corneal ulcer
focal fluorescein staining of the cornea can show corneal ulceration with corneal haze
Refer urgently to ophthalmologist to consider infective, autoimmune causes dn for definitive care