Opthalmology Flashcards
define cartaracts
accumulation of protein in the lens resulting in opacification and vision loss
risk factors for cataracts
old age
diabetes
eye trauma
long term ocular steroid use
presentation of cataracts
decrease in acuity
painless, blurred or cloud vision
glare
change in colour vision
post operative complications of cataract surgery
endophthalmitis
uveitis
retinal detachment
types of AMD
early/intermediate AMD (drusen deposits, near normal vision) late AMD (loss of central vision)
2 forms of Late AMD
atrophic/dry and exutative/wet
risk factors for AMD
age
Fhx
previous cataract surgery
smoking, hypertension, CVD
fundoscopy findings in AMD
early - drusen, loss of retinal epithelium and photoreceptors
dry - thickening of bruch’s membrane, geographical atrophy
wet - subretinal haemorrhage, pigment epithelial detachment, retinal thickening, oedema, lipid exudates
management of AMD
risk modification (cardiovascular risks, smoking, antioxidant and mineral supplements) dry - no current effective treatment wet - VEGF intravitreal injection (ranibizumab)
pharmacological treatment of open angle glaucoma
latanoprost (prostaglandin analogue - increases uveoscleral outflow)
timolol (beta blocker -decrease aqueous humour production)
brinzolamide (carbonic anhydrase inhibitor - decreases aqueous humour production)
brimonidine (a1 agonist - both)
surgical management of open angle glaucoma
trabeculectomy with mitomycin C
tube placement - ahmed valve
laser trabeculoplasty
fundoscopy findings in open angle glaucoma
thinning of the neurosensory rim
nerve fibre layer defect
optic disc rim notching and cupping
cup:disc ratio enlarged (>0.6) or asymmetrical (>0.2 between eyes)
presentation of angle closure glaucoma
sudden onset severe painful, red eye blurred vision halos around lights headache N&V pupil mid dilated and fixed
management of angle closure glaucoma
topical pilocarpine (reduces IOP) IV brinzolamide (carbonic anhydrase inhibitor) YAG laser iridotomy (both eye - prophylactic in the second one)
what is rhegmatogenous RD
detachment due to a retinal discontinuity (break/tear)
Whereas, In the tractional form, RD is caused by proliferative membranes, either on the retinal surface or, less commonly, underneath it (sub-retinal strands). No retinal break is present, although it may subsequently develop (combined rhegmatogenous/tractional RD)
risk factors for retinal detachment
trauma
myopia
previous cataract surgery, laser refractive surgery
family history
presentation of retinal detachment
dense shadowing in peripheral vision moving to central vision
curtains coming down
straight lines appearing curved
floaters or flashing lights
management of retinal detachment
Complete detachment = Vitrectomy + Laser retinopexy/Cryopexy (to Seal any holes/breaks)
Haemorrhagic = retinotomy +/- Gas/Oil bubble injection (Tamponades the break)
bacterial causes of conjunctivitis
pneumococcus
s. aureus,
haemophilus influenzae
Neisseria gonorrhoea
chlamydia trachomatis
viral causes of conjunxtivitis
adenovirus
herpes simplex
epstein barr
presentation of viral conjunctivitis
bilateral
red, watery, itchy
follicles
presentation of bacterial conjunctivitis
unilateral/bilateral
red, sticky, discharge
papillae
common causative organisms in keratitis
bacterial: pseudomonas, s. aureus
viral: herpes simplex, herpes zoster
fungal: aspergillus
risk factors for keratitis
bacterial: CL user, dry eyes, lid disease
viral: Hx of HSV, HZV
fungal: trauma from vegetation, ocular corticosteroid use
findings of fluorescein staining in keratitis
bacterial: oval/round lesion
viral: dentritic (HSV)
fungal: feathery edges, satellite lesions
investigations for keratitis
WCC, CRP
cornel scrapings culture
contact lens and solution culture
fluorescein staining
management of keratitis
bacterial: antibiotics
HSV: aciclovir
fungal: anti fungal
photophobia: cyclopentolate
CL hygiene education
avoid CL use - should avoid use until resolved
difference between a corneal abrasion and a corneal ulcer
abrasions only affect the epithelium
ulcers involve the stroma
how does central retinal artery occlusion present
sudden painless central vision loss
decrease visual acuity
RAPD
clinical features of CRAO
pale/swollen retina
“cherry red spot”
intraretinal haemorrhage
investigations for CRAO
fluoroscein angiogram - shows slow filling arterioles
lipid panel, aPTT, INR, clotting
ECHO
management of CRAO
TIA referral (carotid US/CT head, Aspirin/clopidogrel, no driving for a month)
risk factors for RVO
atherosclerosis systemic hypertension diabetes smoking CVD
how does RVO present
sudden painless vision loss
clinical findings of RVO
tortuous vessels
disc swelling
flame haemorrhages
cotton wool spots
investigations for RVO
fluorescein angiogram
optical coherence tomography
electroretinography
management of RVO
address vascular risk (BP, lipids, DM, smoking)
for macular oedema - VEGF inhibitor, intra vitreal steroids
presentation of AION
NAION = reduced vision in one eye, often obscured by a 'shadow' affecting upper or lower half, painless AAION = + symptoms of temporal arteritis (jaw claudication, scalp tenderness, etc.)
investigations for aaion
ESR, CRP, temporal artery biopsy
management of AION
prednisolone
describe the 2 types of diabetic retinopathy
non proliferative
early stage, leakage of blood vessels -> blurred vision
proliferative
advanced form, neovascularisation -> prone to rupture leading to haemorrhage, vision loss and retinal scarring
features of diabetic retinopathy on fundoscopy
microaneurysms blot/dot haemorrhages hard exudates cotton wool spots new vessels
R0 of diabetic retinopathy
no signs
R1 of diabetic retanopathy
mild - at least one dot haemorrhage/microaneurysm without hard exudates
R2 of diabetic retinopathy
moderate - 4 or more blot haemorrhages in one hemi field
R3 of diabetic retinopathy
severe: any of the following
4 or more blot haemorrhages in both hemi fields
venous bleeding
intraretinal microvascular abnomality
R4 of diabetic retinopathy
proliferative disease: new vessels, vitreous haemorrhage
investigations for diabetic retinopathy
photographs of fundus
optical coherence tomography
fluorescein angiography
management of diabetic retinopathy
glycaemic control
mild = observe/VEGF inhibitor (ranibizumab)
PDR = pan retinal photocoagulation laser
diabetic macular oedema = intravitreal injections (corticosteroids, anti VEGF)
vitreous haemorrhage = vitrectomy
ocular features of hypertension
anterior narrowing cotton wool spots retinal haemorrhages optic nerve swelling retinal ischaemia and neovascularisation
associated with RAO/RVO
how to distinguish between scleritis and episcleritis
episcleritis blanches with phenylephrine drops
scleritis does not
presentation of optic neuritis
painful vison loss
pain on movement of eyes
reduced colour vision
RAPD
Management of optic neuritis
IV methylprednisolone (speeds up recovery but does not improve visual acuity)
features of thyroid eye disease
exophthalmos
restricted movements
lid retraction and swelling
chemosis of conjunctiva
management of thyroid eye disease
smoking cessation
artificial tears and lubrication
systemic steroids if vison affected
surgery (orbital decompression, eye muscle surgery, eyelid surgery)
how does cranial nerve III palsy present
adduction weakness (outwards and downwards)
ptosis
fixed dilated pupil
vertical diplopia
how does 4th nerve palsy present
extorsion of the eye (inability to depress and adduct the eye simultaneously)
head tilt to opposite side of lesion
vertical/oblique diplopia
how does 6th nerve palsy present
esotropia (affected side’s eye drifts towards the midline)
horizontal diplopia
define amblyopia
Strabismus in children may cause suppression (active process of the central nervous system by which the visual input of one eye is ignored) of the image created by the non-fixating eye, resulting in amblyopia (decreased vision in an anatomically normal eye caused by suppression) and irreversible loss of vision if not adequately treated
investigations for strabismus
cover test and prism cover test
uncover test
hirschberg test
krimsky test
management of stribismus
correct any refractive errors
cover the good eye in amblyopia
extraocular muscle surgery
treat any intracranial causes (stroke, masses etc)
causes of acute painless vision loss
CRAO CRVO AION retinal detachment wet ARMD vitreous/retinal haemorrhage (in diabetic retinopathy)
causes of gradual painless vision loss
cataract
open angle glaucoma
diabetic retinopathy
dry ARMD
causes of an acute red eye
conjunctivitis corneal ulcer/abrasions uveitis/iritis acute angle closure glaucoma trauma
presentation of uveitis
anterior = photophobia, pain, reduced vision intermediate = reduced vision, floaters, photopsia posterior = reduced vision, scotoma, floaters, photopsia
signs of anterior uveitis
limbal injection
hypopyon
anterior chamber cells
signs of intermediate/posterior uveitis
vitreous haze
snowballs
multifocal choroiditis
retinitis
management of uveitis
topical pred or dex
systemic steroids if posterior
mycophenolate can be considered
