Presentations Flashcards
what is amblyopia?
reduction is visual acuity due to problem with focussing in early childhood
most commn cause = ‘lazy eye’ (strabismus)
when is surgery for cataracts considered?
visual acuity <6/18 in one or both eyes
pathophysiology of cataracts?
opacification- proteins in lens of the eye degrade over time
Age is main risk factor
a 75 yr old presents with painless loss of vision, and blurring of vision. Whats the likely diagnosis?
Cataracts
On exam: reduced visual acuity on snellen, black against red reflex with slit lamp/ opthalmascope
what is the surgical procedure for cataracts?
phaecoemulsification
lens is dissolved with US and replaced with plastic/ silicone lens
A 63yr old presents with painless loss of vision and blurring. He has a background of DM and has been diagnosed with diabetic retinopathy. Given the likely diagnosis how would you treat?
NOT surgery- diabetic retinopathy contradicts
lifestyle modifications only e.g. not driving at night, help around house to avoid falls
what is Schrimers test?
used to investigate complaints of dry eyes
Strip of filter paper in fornix, measures advancing edge of tears
Occular lubricants for dry eyes?
hypromellose, carbomers
which structure in the eye produces aqueous humour?
ciliary body
open/ closed (acute) angle closure galucoma is most common?
open angle closure glaucoma
slow deterioration of vision
closed (acute) angle closure is medical emergency
glaucoma occurs due to a build up of?
aqueous humour
usually issue with drainage through trabecular meshwork and canal of schlem, rarely can be issue woth production of aqeous humour
is routine screening indicated in glaucoma?
yes- every 2 yrs if strong FHx
every 5 yrs if >40, every 2 yrs if >60
triad of findings in open angle glaucoma?
elevated pressure
optic disc changes
visual loss
medical and surgical mamagament options in open angle glaucoma?
medical: B Blockers, prostaglandin analogues, carbonic anhydrase inhibitors
surgical: trabeculectomy, plastic tube, laser
a 65 yr olf man presents with an extremely red and painful eye. He complains of feeling sick and seeing blurry lines around lights. given the likely diagnosis whst is the treatment?
B blocker (timolol)
Carbonic anhydrase inhibitor (acetazolamide)
Osmotics (glycerin and IV mannitol)
Mitoic (pilocarpine)
Surgical treatment definitively
a 57 yr old lady presents with headaches, malaise and finds it painful to rest her head on her pillo wat night.. She also mentions havign trouble with her vision. Given th elikely diagnosis what is the treatment?
GCA with visual loss- treat with methylprednisolone, then prednisolone + low dose aspirin
a woman presents with suspected giant cell arteritis. Which investigations should you do?
Bloods: ESR + CRP, FBC, LFTs
Temporal artery biopsy –> before/ within 7 days of steroid treatment
how long will a pt with GCA expect to be on steroids i.e. prednisolone for?
12-36 months of steroids (need to reduce dose slowly)
what other drugs are important to co-prescribe with prednislone when treating GCA?
calcium and vit D supplements
consider PPI if increased risk of GI bleeding
what is keratoconus?
progressive thinning of the cornea causing visual disturbances i.e.blurry vision, double vision and photosensitivity
signs and symtpoms of blepharitis?
sore, gritty eyes and sore eyelids
chalazion (granuloma of meibomian glands) and styes (infection of lash follice) more common
red flags for macular degeneration?
decrease in central vision (macula)
distortion of vision
previous vision loss in other eye for macular degeneration
biggest risk factor for ARMD?
smoking- 3-4x inc risk
FHx- 50% chance if 1st degree relative affected
which is more common wet or dry ARMD?
Dry - 75%cases, very gradual change, can progress to wet, hard to treat
wet - vasucalr proliferation under retina causes more sudden change in vision, treatable
62yr old presents with vision changes. He struggles watching the TV and finds it harder to recognise peoples faces. Visual fields are normal. fundoscopy reveals drusen and pale spots on the retina. whats the liekly diagnosis?
Dry macular degeneration
wet would show new vessel formation. scarrign and haemorrhages may also be present
treatment for dry ARMD
high dose vitamin supplements
stop smoking
annual eye exam
treatment for wet ARMD
injections og anti-VEGF
laser therapy targetting new vessels
how do you manage preseptal celliulitis?
oral co-amoxiclav for 10 days + drain lid abscess
hwo do you manage orbital cellulitis?
IV Ceftriaxone + Flucloxacillin + metronidazole for 7-10 days
monitor optic nerve function every 4 hrs
damage to which cranial nerve causes ptosis?
CN III (oculomotor)- lifts upper lid of eye
lid is closed by orbicularis oculi CN VII- facial nerve palsy will not cause ptosis
what is the afferent nerve in the pupillary response?
optic nerve (CNII)
detects lights and sends signal to brain
HOWEVER, defect can be anywhere along afferent pathway i.e. optic chiasm not just within optic nerve itself
what is the efferent nerve in the pupillary response?
Oculomotor nerve (CNIII)
brain recieves signal from EITHER eye and sends signal back down both oculomotor nerves telling pupil to constrict/ dilate
describe the afferent pathway and the efferent pathway?
Afferent: AP in optic nerve, AP travels through L & R lateral geniculate nucleus, axons synapse at L&R pre-tectal nuclei
Efferent: AP passes to L&R Edinger-westpha nuclei, then to L&R ciliary ganglions, constriction of pupil (either direct/ consesual)
a RAPD in the left eye will result in what?
shining light in left eye will result in no constriction of either pupils
shining light in right eye will result in constriction of both pupils
Damage to the left afferent pathway
how will CN III (oculomotor) palsy present?
‘down and out’ pupil on affected side. A dilated pupil that does not respond to light in either eye
However, as afferent is still functioning the contralateral eye will respond to light in both the affect eye and its own light
what is the most common cause of inherited blindness?
Retinitis pigmentosa
>50 causitive genes and variable inheritance patterns
describe the view of the retina in retinitis pigmentosa
pigmentation of periphery
optic atrophy
Investigations for someone with a squint
Visual acuity
cover/uncover test
alternate cover test
assess ocular movements
fundoscopy
determien refractive error
a patient complains of painful loss of vision they described as flashes and then a black curtain. What is the likely diagnosis?
Retinal detachment
painful visual loss(central -> macula), floaters/ flashes, ‘curtain coming down’, common in myopic individuals and diabetics
how do you manage retinal detachment?
small = laser to retinal tears
large = retinal surgery +/- vitrectomy
which complicaiton in Giant cell arteritis can cause painful visual loss?
Temporal Arteritis- central scotoma due to occlusion of the ciliary arteries supplying the optic nerve
treat with prednisolone
a pt presents with painless loss of vision that came on suddenly with black spots. Red reflex in decreased. RBC can be seen in the anterior vitreous. Given the likley diagnosis what is the treatment?
Vitreous Haemorrhage- refer to ophthalmology to confirm rule out retinal detahcment, manage complications i.e glaucoma
usually resolves spontanesouly (surgical vitrectomy rarely required to stop bleeding)
A 75yr old presents with a sudden painless loss of vision particularly in the centre. Opthalmoscopy reveals a hyperaemi retina with engorged veins multiple haemorrhages and cotton wool spots. What is the likely diagnosis?
Central Retinal Vein Occlusion‘stormy sunset’ appearance
what is amaurosis fugax?
TIA of the retina causing transient loss of vision from occlusion of retinal artery
pts need full work up as with any other TIA pt
how do amaurosis fugax and central retinal artery occlusion differ?
CRAO is not transient- needs refered urgently, unlikely to resolve itself if not treated within 30 mintues
Amaurosis fugax will self resolve
patient with IBD has a deep burnign pain in their eye, photophobia and decerased vision. Talbots test is positive (pain increases as tehir eyes converge and constrict) Whats the diagnosis?
Anterior uveitis (iritis)
associated w systemic disease
you’ve diagnosed a pt with anterior uveitis (iritis) you decide to prescribe steroid drops. this is fine right?
NO- need consent from ophthalmologist as if diagnosis wrong could worsen glaucoma, cause cataracts or infeciton
how to differentiate between scleritis and episcleritis?
episcleritis- self limiting, mild pain
scleritis- severe, deep burning pain, photophobia
what can cause a worrying looking really red eye but is actually nothing to worry about?
subconjuctival haemorrhage- will resolve spontaneously in 10-14 days
where would a lesion cause a left sided homonymous hemianopia?
lesion at right optic tract
where would a lesion cause a left sided upper homonymous quadrantopia?
right temporal radiation (meyers loop)
where would a lesion causing a lower qaudrantopia be?
parietal radiation
a pale retina is seen in central vein/ artery occlusion?
Artery occlusion
