Ophthalmololology Flashcards
What is glaucoma?
optic neuropathy, usually due to raised intra-ocular pressure
what is acute angle closure glaucoma
optic nerve damage secondary to rise in intra-ocular pressure due to impairment in aqueous fluid outflow
iris bulges forward and seals off trabecular meshwork
what are the RFs for AACG
hypermetropia
lens growth with age
pupillary dilatation
shallow anterior chamber, chinese ethnicity
what symptoms of AACG
- painful red eye
- headache
- blurry vision
- worse on mydriasis (pupil dilation) (TV in dark)
- dull cornea (corneal oedema)
- hard, red eye
- haloes around lights
- fixed semi-dilated pupil
- systemic upset - nausea, vomiting, abdo pain
what initial treatment of AACG
- lie patient on back without pillow
- pilocarpine eye drops
- acetozolamide
- timolol
- analgesia and anti-emetic
what secondary care treatment of AACG
- pilocarpine
- acetozolamide
- hyperosmotic agents (mannitol/glycerol)
- timolol
- dorzolamide
- brimonidine
what surgical treatment for AACG
bilateral laser iridotomy
how does pilocarpine work
miotic agent
works on muscarinic receptors in iris sphincter, causes constriction of pupil
also causes ciliary muscle contraction
both actions cause pathway to open up for fluid to leave through trabecular meshwork
how does acetozolamide work
carbonic anhydrase inhibitor
- reduces aqueous fluid production
how does timolol work
beta blocker reduces aqueous fluid production
how does brimonidine work
sympathomimetic, reduces aqueous fluid production
what investigation for AACG
gonioscopy and tonometry
what complications of AACG
sight loss
central retinal artery/vein occlusion
what is blepharitis associated with
rosacea
seborrheic dermatitis
what eye drops in blepharitis
hypromellose
polyvinyl alcohol
carbomer
what symptoms of blepharitits
bilateral grittiness discomfort eyelid margins red swollen eyelid sticky eye in morning styes and chalazions secondary conjunctivitis
what are cataracts
cloudiness and opacification of lens
reduced light entering through lens
what are the symptoms of cataracts
gradual onset: reduced vision faded colour vision glare - lights appear brighter than usual haloes around lights
what key sign of cataracts
loss of red reflex
what investigations for cataracts
ophthalmoscopy - normal fundus and optic nerve
slit lamp - cataracts visible
what RFs for cataracts
age smoking alcohol trauma diabetes long term steroids radiation exposure myotonic dystrophy hypocalcaemia
what mgmt of cataracts
conservative if mild symptoms
cataract replacement surgery
what complications following cataract surgery
endopthalmitis
retinal detachment
posterior capsule rupture
posterior capsule opacification
how is endopthalmitis treated
intravitreal antibiotics
what happens if endopthalmitis is untreated
loss of vision/loss of eye itself
which classification of cataract is most associated with steroid use
subcapsular
what are the two main causes of central retinal artery occlusion
thrombosis secondary to atherosclerosis
giant cell arteritis
what are the RFs for central retinal artery occlusion
same RFs as atherosclerosis (smoking hyperlipidaemia HTN obesity diabetes age FH gender etc.)
GCA/PMR
how does central retinal artery occlusion present
sudden painless loss of vision
what investigations for central retinal artery occlusion and what findings
fundoscopy - pale retina and cherry red spot (macula)
ESR raised
temporal artery biopsy if GCA suspected
what management for central retinal artery occlusion
GCA - prednisolone 60mg thrombosis - ocular massage - removal of fluid from anterior chamber to decrease IOP - carbogen (dilates artery) - isosorbide dinitrate (dilate artery)
what long term management of central retinal artery occlusion
treat RFs
secondary prevention of cardiovascular disease
what is conjunctivitis and how does it present
inflammation of conjunctiva
presents with:
sore gritty red eyes with sticky discharge
NOT PAINFUL
no photophobia/visual loss
what are the two main causes of infectious conjunctivitis and how do they present
bacterial - sticky purulent discharge
viral - serous discharge, preauricular lymphadenopathy, associated with recent URTI
how is bacterial conjunctivitis treated
usually resolves within 2 weeks
advise on good hygiene to avoid spreading
- no sharing towels
- no contact lens
- no school exclusion
- clean eyes with cooled boiled water and cotton wool
topical chloramphenicol eyedrops (fucidic acid if preg)
how is neonatal conjunctivitis treated
if under 1m, urgent ophthalmology review
associated with gonococcal infection
can cause loss of sight/pneumonia
how is allergic conjunctivitis treated
topical antihistamines or mast cell stabilisers (sodium cromoglicate)
avoid contact with allergens
how does allergic conjunctivitis present and how is it treated
bilateral symptoms itchy red eyes swelling of conjunctival sac and eyelid history of atopy may be seasonal/perennial (dust mite etc.)
treatment:
avoid contact with allergens
1st line: topical/oral antihistamines
2nd line: sodium cromoglicate (mast cell stabiliser, takes weeks to work)
explain the pathophys of diabetic retinopathy and the findings on ophthalmoscopy
chronic hyperglycaemia causes damage to retinal vasculature and endothelial cells.
this increases vascular permeability, leading to:
- hard deposits
- blot haemorrhages
- microaneurysms
- venous beading
- cotton wool spots (nerve fibre damage, retinal infarction (pre-capillary arteriolar occlusion))
- intraretinal microvascular abnormalities
- neovascularisation
what are the three classifications of diabetic retinopathy
non-proliferative and proliferative
non-proliferative:
- hard deposits
- microaneurysms
- blot haemorrhages
- cotton wool spots
- venous beading
- severe: intraretinal microvascular abnormalities
proliferative:
- neovascularisation
- vitreous haemorrhage
- fibrous tissue forming anterior to retinal disc
diabetic maculopathy
- macular oedema (hard to read, distinguish faces)
- ischaemic maculopathy
what is the 4-2-1 rule of severe non-proliferative diabetic retinopathy
- blot haemorrhages + microaneurysms in all 4 quadrants
- venous beading in at least 2 quadrants
- intraretinal microvascular abnormalities in any quadrant
what treatment for all patients with diabetic retinopathy
- optimise glycaemic control, BP, lipid levels
- regular ophthalmology review
what treatment for patients with diabetic maculopathy
if reduced visual acuity
- VEGF inhibitors
what treatment for non-proliferative diabetic retinopathy
if severe/very severe:
- panretinal laser photocoagulation
what treatment for proliferative DR?
- panretinal laser photocoagulation
- intravitreal VEGF inhibitors
- vitreous haemorrhage - vitroretinal surgery
what symptoms of diabetic retinopathy
- floaters (result of small haemorrhages)
- blurred vision and distortion (central vision if macula affected)
- decreased visual acuity
- loss of vision (severe haemorrhage -> sudden)
- blindness
what investigations in diabetic retinopathy
slit lamp ophthalmoscopy
visual acuity testing (baily-lovie chart)
what is most common cause of visual loss in patients with diabetic retinopathy
diabetic macular oedema
give two examples of VEGF inhibitors
ranibizumab
bevacizumab
what is posterior vitreous detachment and how does it present
detachment of posterior vitreous membrane from retina
- sudden painless floaters
- flashes of light
- blurred vision
- cobwebs
- curtain coming down indicates retinal detachment
what investigations for posterior vitreous detachment
ophthalmoscopy - weiss ring
urgent referral to ophthalmoscopy to exclude retinal tear/detachment
how is posterior vitreous detachment treated
will resolve naturally within 6 months
if retinal tear/detachment - surgical treatment
what are the complications of vitreous detachment
vitreous haemorrhage
retinal detachment
how is diabetic maculopathy treated
intravitreal VEGF-inhibitors if there is a change in visual acuity
what is retinal detachment and what is the most common pathyophys
separation of retina from choroid underneath
rhegmatogenous - tear in retina allows vitreous fluid to enter space between choroid and retina and separate the two layers
what RFs for retinal detachment
- age
- myopia
- previous cataract surgery
- posterior vitreous detachment
- eye trauma
- family history
- previous retinal tear/detachment in either ear
how does retinal detachment present
sudden painless loss of peripheral vision (curtain coming down)
flashes/floaters
blurred/distorted vision
visual acuity may be reduced to hand movements if macular involvement
what is the immediate mgmt of suspected retinal detachment
immediate referral to ophthalmology
- slit lamp
- indirect ophthalmoscopy, pigment cells, vitreous haemorrhage
- red reflex lost on fundoscopy
what examination and investigation findings would you expect in retinal detachment
- reduced peripheral visual acuity
- central acuity reduced to hand movements if macular involvement
- RAPD if optic nerve involvement
- red reflex lost on fundoscopy
- retinal folds pale, opaque, wrinkled
- fundoscopy may appear normal if small break?
what treatment for retinal tears
- cryotherapy
- laser therapy
what treatment for retinal detachment
vitrectomy
scleral buckling
pneumatic retinoplexy
what is periorbital/preseptal cellulitis
infection of tissues anterior to orbital septum
how does periorbital cellulitis present
swollen painful red eye
swollen red eyelid
may get ptosis
how does orbital cellulitis present
chemosis proptosis painful, restricted eye movements proptosis RAPD
what investigations for periorbital cellulitis
- raised inflammatory markers
- swab any discharge
- contrast CT orbit if orbital cellulitis suspected
what is the mgmt for periorbital cellulitis
secondary care referral
admit for monitoring
oral Abx - co-amox
what RFs for orbital cellulitis
- recent URTI
- previous sinus infection
- lack of Hib vaccination
- periorbital cellulitis
- ear/facial infection
how does orbital cellulitis present
- redness and swelling around eye
- severe eye pain
- painful eye movements/ophthalmoplegia
- reduced visual acuity
- proptosis
- nausea, vomiting, drowsiness
- RAPD
how is orbital cellulitis diagnosed
- FBC - WCC raised CRP raised
- ophthalmological assessment
- CT with contrast - inflammation of orbital tissues deep to septum. Sinusitis
- Blood cultures and culture of swab for organism
how is orbital cellulitis managed
admit to hospital for IV Abx
surgical drainage if abscess
what is open angle glaucoma
increased resistance through the trabecular meshwork
decreased outflow of aqueous humour.
gradual increase in IOP
what are the RFs for open angle glaucoma
age
FH
afrocaribbean
myopia
what are the symptoms of open angle glaucoma
- gradual onset tunnel vision
- blurred vision
- headaches
- gradual onset fluctuating pain
- haloes worse at night
what screening investigation for open angle glaucoma
non-contact tonometry
what are the main gold-standard investigations for open angle glaucoma
- goldmann applanation tonometry (>21mmHg)
- fundoscopy (cupping of optic disc)
- visual field testing (peripheral visual loss)
what treatments for open-angle glaucoma
- latanoprost
- timolol
- dorzolamide
- brimonidine
trabeculectomy
how does latanoprost work and what side effects
latanoprost is prostaglandin analogue
- increases uveoscleral outflow
how does timolol work
beta blocker
- reduces production of aqueous humour
how does dorzolamide work
carbonic anhydrase inhibitor
- reduces production of aqueous humour
how does brimonidine work
sympathomimetic
- reduce production of aqueous humour AND increases uveoscleral outflow
what is keratitis
inflammation of cornea
what are the symptoms of keratitis
- painful red eye
- gritty, foreign body sensation
- photophobia
- hypopyon may be seen
what are the different types of keratitis
bacterial
- S. Aureus
- Pseudomonas in contact lens wearers
amoebic
- acanthamoebic keratitis (soil, contaminated water)
- fungal
- parasitic
- viral (herpes simplex keratitis)
what management for bacterial keratitis
- refer to ophthalmology as sight threatening
- stop wearing contact lenses until symptoms fully resolved
- topical Abx - quinolones (ciprofloxacin)
- cycloplegics for pain relief (cyclopentolate)
what complications of keratitis
corneal scarring
visual loss
endophthalmitis
perforation
what is herpes keratitis
caused by herpes simplex
what symptoms of herpes keratitis
- painful red eye
- eye watering
- foreign body sensation
- photophobia
- reduced visual acuity
- vesicles around eye
what investigations for herpes keratitis
fluorescein staining - dendritic ulceration
slit-lamp examination required to diagnose
swabs for viral culture/PCR
what management for herpes keratitis
- urgent same day ophthalmology referral
- topical acyclovir
- ganciclovir gel
- topical steroids if stromal keratitis
corneal transplant may be required if scarring due to stromal keratitis
what is iritis/ant uveitis
inflammation of iris and ciliary bodies
what RFs for ant uveitis
HLA-B27 TB sarcoidosis HSV syphilis Lyme disease Behcet's (HLA-B51)
can also be trauma, infective, ischaemic, malignancy related
what symptoms/signs of ant uveitis
- painful red eye, worse on movement
- blurred vision
- floaters and flashes
- lacrimation
- photophobia (ciliary muscle spasm)
- miosis (small pupil)
- irregular pupil (posterior synechiae)
- ciliary flush
- hypopyon
what investigations for anterior uveitis
full slit-lamp assessment
what management in ant uveitis
urgent ophthalmology referral
cycloplegic-mydriatics
- cyclopentolate/atropine eye drops
steroid eye drops
DMARDs, TNF inhibitors
vitrectomy, laser surgery, cryotherapy
how does cyclopentolate work in ant uveitis
anti-muscarinic
relaxes pupil
what does cycloplegic mean and how is it relevant in ant uveitis
antimuscarinic
paralyses ciliary muscle
stops ciliary muscle spasm and associated pain
what does mydriatic mean
dilates pupils
reduces pain
what complications of ant. uveitis
cataracts
visual loss
