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Flashcards in Blurred Vision Deck (100)
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How to test which eye is causing diplopia

Looking in direction of diplopia and cover one eye followed by the other - ask which eye is seeing the outer image - this is the eye which is malfunctioning


What is hypopyon

Pus in anterior chamber


What is hyphaema

Blood in anterior chamber


How are pupils in anterior uveitis

Small and irregular


How are pupils in acute glaucoma

Fixed, dilated and oval


What is the medical term for stye and what is it

Hordeolum externum - inflammatory eyelid swelling - open staphlococcal infection in the lash follicle. Point outwards and cause inflammation - treated with local antibiotic eg. fusidic acid


Name for stye that is not infected

Marginal cyst


What is chalazion

Also called hordeolum internum - internal abscess where opens into conjunctiva


What is blepharitis

Lid inflammation from staph, seborrhoeic dermatitis or rosacea. Burning itching red margins and scales on lashes
Treat by cleaning off crusts and then Tears Naturale, fusidic acid, steroid drops or oral doxy


What is entropion (eye)

Lid inturning associated with degeneration of lower lid fascial attachments and muscle
Causes irritation
Can taper lower lashes to cheek or botox or surgery for longer lasting effects


What is ectropion (eye)

Lower lid eversion causing irritation, watering and exposure keratitis
associated with old age and facial palsy
Surgical correction


What is a dendritic ulcer

Herpes simplex corneal ulcer which causes severe pain, photophobia and watering


Investigation of dendritic ulcer

1% fluorescein drops stain the lesion green


Treatment of dendritic ulcer

Treat with aciclovir 3% 5x daily


Features of orbital cellulitis

Inflammation of orbit, fever, lid swelling, decreased eye mobility


Cause of orbital cellulitis

Infection spread via paranasal sinuses, eyelid, dental injury/infection or external ocular infection
by Staphs, strep pneu, strep pyogenes or milleri


Treatment of orbital cellulitis

CT, ENT and opthalmic opinion
Need to prevent spread to meninges or cavernous sinus


Risk with orbital cellulitis

Spread and also blindness from pressure on optic nerve or vessel thrombosis


Typical presentation of opthalmic shingles (herpes zoster opthalmicus)

Pain and neuralgia in opthalmic division followed by a blistering inflamed rash
50% have affected globe therefore having corneal signs with or without iritis


What is an indicator in HZO that the globe might be affected

If the nose tip is involved (Hutchisons sign) then the nasociliary branch is affected and this nerve also supplies the globe


Treatment of HZO

Famiciclovir - 750mg OD for 1 week - better regimen but more expensive than Aciclovir 800mg 5x day for 1 week (aciclovir also has more serious side effects eg. hepatitis and renal failure)


Signs of retinoblastoma

Strabismus and leukocoria (white pupil)
Red reflex is absent!!


Inheritance and genetics of retinoblastoma

Inherited autosomal dominant with 80% penetrance
RB gene is a tumour suppressor gene
Usually inherit one altered allele - if developing mutation occurs in other allele then tumour arises


What can occur as a secondary in retinoblastoma

Secondary malignancies such as osteosarcoma or rhabdomyosarcoma


Treatment of retinoblastoma

Moving away from eye removal surgery and towards other options such as chemo, targeted radio, enucleation etc


What is esotropia

One eye turned in aka convergent squint - commonest type in children


What is exotropia

Divergent squint, one eye turns out - more common in older children and often intermittent


Management of squint

3 O's - Optical (cyclopentolate drops to see refractive error and if any other diagnoses - then give glasses)
Orthoptic - cover the good eye, forces bad eye to be used
Operation - rectus muscle resection and recession


What happens in 3rd CN palsy

Oculomotor nerve affected - ptosis and proptosis due to decreased recti tone
Fixed pupil dilation and eye looking down and out


What happens in 6th CN palsy

Abducens nerve - diplopia in horizontal plane, eye medially deviated and cannot move laterally from midline (lateral rectus paralysed)