Ophthalmology Flashcards
What is open angle glaucoma?
it is damage to the optic nerve due to raised IOP leading a blockage of the aqueous humour leaving the eye
rise of IOP over 21mmHg leads to increase in resistance and further pressure - chronic
acute - iris bulges and seals off the meshwork
what is the normal role of the aqueous humour?
it supplies the nutrients to the cornea - made by the ciliary body
flows from CB around the lens and under the iris, through the anterior chamber and into canal of schlem which enters circulation
what are the risk factors for open angle glaucoma?
increasing age, FHx, black, myopia
how does open angle glaucoma affect the optic disc?
it causes cupping
how does open angle glaucoma present?
can be asymptomatic for a long time - routine screening picks it up
affect peripheral vision first resulting in tunnel vision, gradual onset fluctuating pain, headaches, blurred vision and haloes at night
how is open angle glaucoma investigated?
air puff or Goldmann applanation tonometry, fundoscopy, visual field assessment
how is open angle glaucoma managed?
management starts at 24mmHg
prostaglandin eye drops such as lantaprost to increase outflow
BB to reduce production
carbonic anhydrase inhibitors to reduce production
sympathomimetics
trabeculectomy
what is the pathophysiology of acute angle closure glaucoma?
the iris bulges forwards and seals off the trabecular network from anterior chamber so the aqueous humour cannot escape
what are the risk factors for acute AC glaucoma?
increasing age, female, FHx, chinese, east asian, shallow anterior chamber, drugs
how does acute AC glaucoma present?
unwell, severely painful red eye, blurred vision, haloes, headache, N+V
red teary eye
hazy cornea
decreased VA
dilatation of the affected pupil
fixed pupil size
firm eyeball on palpation
how is acute AC glaucoma managed?
initially - lie on back, pilocarpine eye drops, acetazolamide, analgesia, antiemetics
secondary care - pilocarpine, acetazolamide, hyperosmotic agents, timolol, dorzolamide, brimonidine, laser iridotomy
what is diabetic retinopathy?
it is when the retinal vessels are damaged due to chronic hyperglycaemia, this damage causes hard exudates, blot haemorrhages, microaneurysms, cotton wool spots, intraretinal microvascular abnormalities, neovasculariation
what is the difference between proliferative and non proliferative diabetic retinopathy?
proliferative - neovascularisation and vitreous haemorrhage
non - mild, moderate and severe all signs except neovascularisation
what is diabetic maculopathy?
it is macular oedema and ischaemia maculopathy
how is diabetic retinopathy managed?
laser photocoagulation, antiVEGF, vitreoretinal surgery
what are complications of diabetic retinopathy?
retinal detachment, vitreous haemorrhage, rebeosis iridis, optic neuropathy, cataracts
what is ARMD?
it is macular degeneration that can be wet (10%) or dry (90%)
results in drusen, atrophy of retinal pigment epithelium, degeneration of photoreceptors
what is wet ARMD?
it is new vessels from choroid layer into retina, which then leaks, results in oedema and more visual loss - stimulated by VEGF
how is ARMD investigated?
decreased VA, scotoma, Amsler grid testing, drusen on fundoscopy, slit lamp biomicroscopic fundus exam, optical coherences tomography, fluroescein angiography
how does ARMD present?
gradual worsening central vision, decreased acuity, crooked or wavy appearance to straight lines, more acute if wet
how is ARMD managed?
avoid smoking, control BP, vitamin supplementation
wet - antiVEGF monthly
what controls pupil constriction and dilatation?
circular muscles in iris controlled by PNS through oculomotor control - constriction
dilatation - dilator muscles are stimulated by SNS using adrenalin
what can result in an abnormal shaped pupil?
trauma, anterior uveitis, acute ACG, rubeosis iridis
what causes mydriasis?
third nerve palsy, Holmes Adie syndrome, increased ICP, trauma, congenital, stimulants, anticholinergics
summarise Horners?
it is ptosis, miosis, enopthalmos and anhidrosis
causes - stroke, MS, syringomyelia, tumour, trauma, thyroidectomy, carotid artery dissection, cavernous sinus thrombosis, cluster headaches
ix - cocaine drops give no response, adrenalin drops will dilate horners pupil but not a normal pupils
what can cause miosis?
horners, cluster headaches, opiates, nicotine, Argyll Robertson pupil
summarise CNIII palsy?
ptosis, non reactive dilated pupil, divergent strabismus
idiopathic, DM, HTN, ischaemia, ICP, tumour, trauma
what is Holmes Adie puil?
unilateral dilated pupil with sluggish reaction to light that gets smaller over time
absent knee and ankle reflexes - HA syndrome
can be viral cause
what is a Argyll Robertson pupil?
neurosyphilis - accommodates to near object but not light, irregular and constricted
summarise belpharitis?
inflammation of the eyelid margins
gritty, itchy, dry eye
can lead to styes and chalzions
mx - hot compress, lubricant eye drops, keep clean
summarise stye?
externum is glands of Zeus or Moll
internum is Meibomian
tender red lump on eye lid
mx - analgesia, hot compress, topical ABx if required
summarise trichiasis?
inward eyelash growth - corneal damage and ulceration
mx - epilation, electrolysis, cryotherapy, laser
summarise orbital cellulitis?
infection involving the orbital septum, preceded by preseptal (swelling, redness, hot skin - CT to r/o orbita, give IV ABx or PO, admission if needed)
as before plus pain on eye movement, decreased movement, abnormal pupil reactions, forward movement of eye ball
IV ABx and drainage if needed
summarise ectropion?
eyelid turns out - commonly bottom
exposure keratopathy
mild - conservative with eye drops
severe - same day referral
summarise entropion?
eye lid inverts - corneal damage and ulceration
mx - tape eyelid, lubrication, urgent referral
summarise chalazion?
blocked meibomian gland
non tender eyelid swelling
mx - compress and analgesia
topical ABX and surgical drainage if needed
what is a cataract?
it is when the lens becomes cloudy and opaque - decreased VA
it is screened for at birth
can be caused by increasing age, smoking, alcohol, DM, steroids, decreased Ca
how does cataract present?
asymmetrical, very slow visual reduction and blurring, change in colour vision, starbursts, loss of red reflex
how is cataract managed?
manage symptoms, surgery for artificial lens, r/v after operation as it can cover up other issues
what is endophthalmitis?
serious rare complication of cataract surgery - overwhelming infection and inflammation of eye - intravitreal ABx
what is conjunctivitis?
it is inflammation of the conjunctiva - inside of the eye lid to sclera
can be bacterial, viral, allergic etc
what is the presentation of conjunctivitis?
bacterial - purulent discharge, inflamed conjunctiva, eyes stuck together in morning, contagious, spreads uni to bilateral
viral - clear discharge, dry cough, sore throat, blocked nose, tender periauricular noes
allergic - swelling of conjunctival sac, watery discharge, itch
generally - uni or bilateral, red, bloodshot, itchy, gritty, discharge, no pain, decreased VA or photophobia
how is conjunctivitis managed?
allergic - antihistamines, topical mast cell stabilisers
self resolving otherwise, good hygiene, cooled boiled water and cotton wool, avoid contact lenses, topical chloramphenicol and fusidic acid is needed
refer neonates
what is hypertensive retinopathy?
it is damage to the small blood vessels in retina due to HTN
silver or copper wiring, AV nipping, cotton wool spots, hard exudates, retinal haemorrhages, papilloedema
how is hypertensive retinopathy managed?
control BP and RFs
what is anterior uveitis?
it is inflammation of the anterior uvea (iris, CB, and choroid)
infiltration by neutrophils, lymphocytes, macrophages - autoimmune, infection, trauma, ischaemia and cancer can cause
what are the associations of uveitis?
acute - HLAB27
chronic - granulomatous - TB, HSV, Lymes, sarcoidosis, syphilis
how does anterior uveitis present?
floaters, unilateral dull, aching, painful, red
ciliary flush, decreased VA, miosis, photophobia, hyperlacrimation, pain on movement, abnormal shaped pupil, hypopyon
how is anterior uveitis managed?
urgent same day referral, steroids, cycloplegic mydriatics, immunosuppressants, laser cryotherapy, vitrectomy
what is episcleritis?
it is a benign, self limiting inflammation of the episclera
how does episcleritis present?
mild pain, segmental redness, lateral FB sensation, dilated vessels, watering, no discharge
how does scerlitis present?
it is pain, with movement, eye watering, decreased VA, photophobia, abnormal light reactions, tender on palpation
how is episcleritis managed?
refer to ophthalmology, self limiting, lubricants, cold compress, analgesia, safety net, top steroid drops, systemic NSAIDs
what is scleritis and how is it managed?
it is full thickness inflammation of the sclera that can result in necrosis
same day referral, investigate for underlying condition, NSAIDs and steroids, immunosuppressants appropriate to underlying condition
what are corneal abrasions?
they are scratches or damage to the cornea resulting in a painful red eye, FB sensation, history of contact lenses or FB, watering, photophobia, blurred vision
can cause severe damage and loss of vision
how is corneal abrasion investigated?
fluorescein stain
slit lamp
how is corneal abrasion managed?
same day referral
remove FB
simple analgesia, lubricating eye drops, irrigation if chemical, cyclopentolate
what is a corneal ulcer?
it is more common in contact lenses - causes eye pain, photophobia, watering, focal staining
mx - treat cause
what is herpes keratitis?
inflammation of the cornea - HSV most common but also pseudomonas, staph, fungal, contact lens acute red eye and exposure
what is a complications of herpes keratitis?
stromal keratitis - inflammation of stroma - vascularisation, necrosis, scarring - blindness
how does herpes keratitis present and how is it diagnosed?
painful red eye, photophobia, vesicles around eye, FB sensation, watering, reduced VA
fluorescein stain - dendritic corneal ulcers, slit lamp, swabs and scrapings for PCR
how is herpes keratitis managed?
aciclovir topical or oral
gangciclovir gel
steroids antivirals
stromal - corneal transplant
what is a subconjunctival haemorrhage?
small vessel in conjunctiva ruptures and released into space between sclera and conjunctiva
associated with HTN, bleeding disorders, pertussis, drugs, NAI
how does subconjunctival haemorrhage present?
bright red patch, painless, no visual change, hx precipitating event
how is subconjunctival haemorrhage managed?
self resolving around 2w
investigate underlying cause
lubricating eye drops if FB sensation
what is a posterior vitreous detachment?
the vitreous body becomes less firm with age and gradually withdraws from retina
how does posterior vitreous detachment present?
painless, spots of loss of vision, floaters, flashes
how is posterior vitreous detachment managed?
the symptoms improve as the brain adjusts
can predispose to retinal tears and detachment - r/o so refer to ophthalmology
what is retinitis pigmentosa?
it is a congenital inherited condition of degeneration of rods and cones
mostly rods>cones
presents with night blindness, loss of central and peripheral vision
what conditions are associated with retinitis pigmentosa?
Ushers, Basser Kornzweig, Refsums
how is retinitis pigmentosa investigated?
pigmentation, arteriole narrowing and pale optic disc on fundoscopy
how is retinitis pigmentosa managed?
refer, genetic counselling, vision aids, sunglasses, inform DVLA, f/u regularly, vitamin and antioxidants, PO acetazolamide, TOP dorzolamide, steroid injections
what is retinal vein occlusion?
a thrombus forms in the retinal veins - one of the four small or central
results in pooling of blood, fluid leak, macular oedema and retinal haemorrhage, lost vision and release of VEGF - neovascularisation
sudden painless loss of vision
what are risk factors for retinal vein occlusion?
hypercholesterolaemia, DM, smoking, glaucoma, SLE
how is retinal vein occlusion investigated and managed?
fundoscopy - flame and blot haemorrhages, optic disc oedema, macular oedema
FBC - check leukaemia, ESR, BP, glucose
mx - refer - laser photocoagulation, intravitreal steroids, antiVEGF
what happens in retinal detachment?
flow of blood is blocked from vessels of choroid body to retina - sight threatening
retinal separation from choroid due to retinal tear allowing vitreous fluid to get under retina and fill space between retina and choroid
how does retinal detachment present?
peripheral visual loss, blurred or distorted vision, flashes, floaters
how it retinal detachment managed?
tears - laser or cryotherapy
detachment - vitrectomy, scleral bulking, pneumatic retinopexy
what is central retinal artery occlusion?
when the flow of central retinal artery is blocked
usually due to atherosclerosis or GCA
what are risk factors for central retinal artery occlusion?
increasing age, FHx, smoking, DM, HTN, alcohol, poor diet, inactivity, obesity, female>50, GCA, PMR
what is the presentation of central retinal artery occlusion?
sudden, painless loss of vision, RAPD, pale retina, cherry red spot
how is central retinal artery occlusion managed?
refer
GCA - ESR and TA biopsy, high dose steroids
ocular massage, remove fluid from anterior chamber to reduce IOP
inhaled carbogen
sublingual isosorbide dinitrate
prevent and treat RFs and secondary prevention of CVD
