Opthalmology Flashcards
Giant cell arteritis
Optic nerve ischaemia > sudden blindness
Iritis associations
AS, reiters, etc
Scleritis/ episcleritis
RA, SLE, vasculitis
Episcleritis not painful
Hypertensive retinopathy
BP accelerates atherosclerosis in retinal vessels.
Silver wiring - Hardened arteries are shiny and ‘nip’ veins where they cross
Cotton wool spots - Narrowed arterioles > blocked > localized retinal infarction
Leaks from these in severe HTN > hard exudates or macular oedema.
Papilloedema or flame haemorrhages
suggest accelerated hypertension
Infective endocarditis
Roth spots - small retinal infarcts
Retinal vein occlusion
HTN, age, hyperviscosity
Stormy sunset (fundus) - central vein, if branch then wedge of retina
Acute drop acuity
AIDS HIV
CMV retinitis, lone cotton wool spots - HIV retinopathy
Acute glaucoma
Both ciliary and conjunctival vessels injected. Entire eye is red. Injected iris Pupil dilated, fixed Cornea hazy Anterior chamber very shallow High intraocular pressure
Open angle - blockage in drainage of aqueous humour
> increased IOP
Chronic
Tx - prostaglandin analogue (latanoprost) - relaxes ciliary muscules > lowers IOP
laser - open angle
Closed - angle between iris and cornea too small (lens being pushed against iris) > block
Acute - IV acetazolomide - carbonic anhydrase inhibitor - diuresis
pilocarpine drops
peripheral iridotomy - closed angle
Iritis
Injected iris
Pupil adhesions so irregular
Redness most marked around cornea, which
doesn’t blanch on pressure.
Usually unilateral.
Causes: AS, RA, Reiter’s, sarcoidosis, HSV, herpes zoster, and Behçet’s disease.
NB: a similar scleral appearance but without
papillary or anterior chamber involvement
may be scleritis (eg RA, SLE, vasculitis).
Refer -steroid eye drops
Conjunctivitis
Often bilateral. Conjunctival vessels injected, greatest toward fornices, but blanching on pressure. Mobile over sclera. Purulent discharge.
Subconjunctival
haemorrhage
Causes: HTN; leptospirosis; bleeding
disorders; trauma; snake venom; haemorrhagic
fevers.
Dendritic ulcer
Photophobia & watering.
If steroid drops are used without aciclovir cover, corneal invasion and scarring may occur, risking blindness.
1% fluorescein drops stain the lesion. :
Aciclovir 3% eye ointment 5≈ daily.
Ophthalmic shingles
Pain and neuralgia in the distribution of
cranial nerve V1 dermatome
blistering rash. In 50% of those with HZO the
globe is affected (corneal signs ± iritis in >40%—
sectoral iris atrophy
Nose-tip (Hutchison’s sign) -nasociliary branch of the trigeminal nerve also supplies the globe >likely eye affected.
The eye can be affected with little rash elsewhere.
Varicella zoster virus (VZV) may persist in the eye.
The different patterns of retinal disease caused
by VZV relate to immune status.
Oral antivirals improve symptoms (additional antiviral drops are not needed) but cannot be relied on to prevent postherpetic neuralgia.
Famciclovir offers the best dose schedule (750mg once daily for 1wk; SE vomiting; headache) but is much more expensive than aciclovir (800mg 5 times daily
PO for 7 days—it has more serious SE such as hepatitis and renal failure).
Start within 4 days of onset. It is wise for all to see a specialist if the nose-tip is involved, or the eye turns red within 3 days, to exclude anterior uveitis with a
slit lamp. Prolonged steroid eyedrops may be needed.
Retinoblastoma
most common primary intraocular tumour in children
Strabismus and leukocoria
Autosomal dom
RB gene
5% occur with a pineal or other tumour
Secondary malignancies such as osteosarcoma and rhabdomyosarcoma
are more frequent
Third nerve palsy (oculomotor)
Ptosis (levator palpebrae), proptosis (as recti tone), fixed pupil dilatation (constrictor pupillae), with the eye looking down and out.
cavernous sinus lesions
superior orbital fissure syndrome
diabetes
posterior communicating artery aneurysm.
Fourth nerve palsy (trochlear)
Diplopia
patient may hold his head tilted (ocular torticollis).
The eye looks upward, in adduction and cannot look down and in ( paralysed).
Causes: Trauma 30%, diabetes 30%, tumour, idiopathic.
Trochlear - superior oblique - this looks down and out
Sixth nerve palsy (abducens)
There is diplopia in the horizontal plane.
Lateral rectus
Medially deviated and cannot move laterally from midline
Causes: Tumour raising ICP (compresses
the nerve on the edge of the petrous temporal bone), trauma to base of skull, vascular, or MS
Botulinum toxin can eliminate need for strabismus surgery in selected VI palsies
Absent direct response RAPD
Problem with afferent pathway
Optic neuritis, optic atrophy, retinal disease
Consensual response present
If the pupil dilates during swinging test – Marcus Gunn pupil
Horner’s syndrome
disrupting sympathetic fibres
miosis, partial ptosis, and the pupil does not dilate
in the dark.
Unilateral facial anhydrosis may indicate a lesion proximal to the carotid plexus—
if distal, the sudomotor (sudor = sweat) fibres
will have separated, so sweating is intact.
Congenital Horners: iris heterochromia
Holmes–Adie pupil
Initially monolateral, then bilateral, pupil dilatation with
delayed responses to near vision effort, with delayed redilation.
Young woman, with sudden blurring of near vision, and a dilated pupil, slow responses to accommodation, and, especially, to light (looks unreactive,
unless an intense light is used for >15min), ie a tonic pupil.
Slit lamp exam:
Iris shows spontaneous wormy movements (iris streaming).
Holmes–Adie syndrome: Tonic pupil, absent knee/ankle jerks and low BP
Argyll Robertson pupil
neurosyphilis, diabetes
bilateral miosis, pupil irregularity
no response to light
response to accommodation (the prostitute’s pupil
accommodates but does not react).
The iris is spongy, the pupils dilate poorly, and there may be ptosis.
Myopia
Short sighted
Eyeball long
Concave spectacles
Hypermetropia
Long sighted
Eye short
Convex glasses
Presbyopia
ciliary muscle reduces tension in the lens, allowing it to get more convex, for close focusing. Lens stiffens.
Marfans syndrome
Sudden painless loss of vision
Lens disolocation
Marfan's syndrome: upwards homocystinuria: downwards Ehlers-Danlos syndrome trauma uveal tumours autosomal recessive ectopia lentis
Tunnel vision
glaucoma, retinitis pigmentosa
Cataracts operation complications
Retinal detachment/ rupture
Endophthalmitis
Posterior capsule opacification
Chalazion
meibomian cyst and is typically on the internal eyelid.
hordeolum externum
infection of the glands of the external eyelid
stye
blepharitis
inflammation of the eyelid margins typically leading to a red eye. no lump.
Marcus gunn pupil
RAPD lesion of optic nerve, MS, glaucoma effected eye - no response other eye - constricts effected eye - dilates
Anterior ischaemic optic neuropathy
Sudden loss of vision Pale optic disc Posterior ciliary arteries > inflammation > optic nerve damage PREDNISOLONE GCA, htn, hyperlipid
Retinal artery occlusion
Sudden loss of vision
Urgent tx < 6 hours
Vitreous haemorrhage
Neovascularisation, retinal tears or detach,
Floaters
Absorbs back normally
Optic neuritis
Loss of red vision
Painful eye movements
> MS
Methylprednisolone
Central retinal vein occlusion
whole vein > visual loss
Stormy sky
Central artery occlusion
Sudden visual loss
Pale retina
Cherry spot macula
within 6h of onset aim is to increase retinal blood fl ow by
reducing intraocular pressure by ocular massage, surgical removal of aqueous
from the anterior chamber or the use of antihypertensive treatment
Retinal detachment
Post trauma, cataracts, tumours > myopic eyes 4Fs - flashes, floaters, field loss, fall in acuity Painless curtain falling > urgent surgery
Amaurosis fugax
Transient loss of vision
Vascular causes eg TIA
ARMD
cheif cause of blindness
lose central vision
dry - drusen
wet - neovascularisation - tx vegf inhibitors
Open angle glaucoma
tunnel vision
first line: prostaglandin analogue (PGA) eyedrop
second line: beta-blocker, carbonic anhydrase inhibitor, or sympathomimetic eyedrop
if more advanced: surgery or laser treatment can be tried2
Retinitis pigmentosa
Sporadic, AR, some AD
