Pathology Flashcards
what are eye cataracts
opacification / clouding of the lens
causes of cataracts
age diabetes sunlight - UVB steroids hypertension smoking ocular trauma metabolic disorders genetic
symptoms of cataracts
gradual painless loss of vision
diplopia
difficulty reading / writing
halos around lights
signs of cataracts on examination
clouded lens
absent red reflex
management of cataracts
phaco-emulsification with intra ocular lens replacement surgery
what is a consequence of uncorrected cataracts in children
amblyopia (lazy eye) - eye fails to achieve visual acuity and vision does not develop properly
what is conjunctivitis
inflammation of the conjunctiva
what is scleritis
inflammation of the sclera
symptoms of scleritis
associated with pain on movement
red eye
impaired vision
associated with autoimmune conditions - SLE, RA
phenylephrine testing in scleritis is positive/negative
negative
what is episcleritis
inflammation of episclera
symptoms of episcleritis
no pain on movement
superficial
self limiting
phenylephrine testing in episcleritis is positive/negative
positive
How can you differentiate between scleritis and episcleritis
phenylephrine drops will cause blanching of vessels in episcleritis (positive) and no change in scleritis (negative)
what is glaucoma
progressive optic neuropathy usually due to an abnormal increase in intra-ocular pressure as a result of blockage to aqueous humour drainage (trabecular meshwork or canal of Schlemm)
what ultimately happens in glaucoma
pressure builds up and greatly impacts on optic nerve/disc resulting in a blindspot
what are the types of glaucoma
open and closed angle
which is more common, open or closed angle glaucoma
open angle
what is the pathology behind open angle glaucoma
blockage of drainage of aqueous humour
onset of open angle glaucoma
slow onset
asymptomatic
signs of open angle glaucoma on fundoscopy
cupping of the optic disc
characteristic field changes
raised IOP
what is the pathology behind closed angle glaucoma
the drainage system is fine but the iris BULGES FORWARD to block drainage angle meaning fluid can’t circulate and it accumulates behind the iris
acute closed angle glaucoma is an emergency, true or false
true!
symptoms of closed angle glaucoma
acute red eye severe headache N+V hazy cornea fixed mid dilated pupil reduced vision pain
management of closed angle glaucoma
laser a hole through the iris
what is ARMD
ARMD is characterised by appearance of drusen in the macula
what is drusen
fatty protein and lipid deposits
what are the types of ARMD
dry and wet
describe dry ARMD
no significant vascular proliferation
more common
less severe
essentially wear and tear of RPE layer
describe wet ARMD
significant vascular proliferation always begins as dry ARMD neurovascularisation in choroid mediated by VEGF these new vessels are leaky and fragile more likely to lead to loss of vision
management of dry ARMD
conservative
management of wet ARMD
monoclonal Ab to VEGF
commonest causes of retinopathy
hypertension and DM
what is an Argyll Robertson Pupil
ocular sign
usually seen bilaterally
accommodates but does not react
causes of an Argyll Robertson Pupil
late stage neurosyphilis
DM
MS
stroke
what is rubeotic glaucoma
neovascularisation on surface of the iris
seen in severe DM or severe retinal vein occlusion
features of diabetic retinopathy
leaky vessels aneurysms oedema dot and blot haemorrhages flame haemorrhages
what is papilloedema
swelling of the optic disc die to raised intracranial pressure
what is CRAO (central retinal arterial occlusion)
blockage of the central retinal artery
eg amaurosis fugax ~ TIA of the eyes
usually from the carotids and thromboembolic disease
describe vision loss in amaurosis fugax
vision loss like a curtain coming down
what is CRVO (central retinal vein occlusion)
blockage of the central retinal vein
eg GCA vasculitis
eg atherosclerosis of neighbouring artery impinging on vein
in which neurological condition can optic neuritis be seen
what is a sign of this
MS
RAPD
what is a cause of ischaemic optic neuropathy
GCA
what investigations are used to monitor signs in glaucoma
IOP - tonometry
visual fields - perimetry
optic disc - fundoscopy
risk factors for open angle glaucoma
age
raised IOP
afro-carribean
FH
what is the name of surgery for open angle glaucoma
trabeculectomy
patient with which refractive error have an increased risk of closed angle glaucoma
hypermetropes
management of closed angle glaucoma
reduce IOP medically
peripheral iridotomy
what is the pathogenesis in wet ARMD
eye grows new blood vessels within the macula to ‘repair’ dry ARMD
new vessels are leaky and so bleed into retinal tissue
CRAO treatment is only effective if presentation is within 12-24 hours, true or false
true
management of CRAO
ocular massage
paper bag breathing
IV diamox
anterior chamber paracentesis
management of CRVO
no signs of ischaemia - observe every 3 months
ischaemia but no neovascularisation - observe every 4-6 weeks
ischaemia + neovascularisation - urgent PRP
what is Horner’s syndrome
paralysis of sympathetic supply to the eye
- mild ptosis
- constriction of pupil
- anhydrosis
risks of corneal transplant
rejection astigmatism glaucoma uveitis retinal detachment
risk factors for retinal detachment
myopia
previous eye trauma / surgery
FH
complications of lens replacement surgery
endophthalmitis
unexpected refractive error
pathophysiology of thyroid eye disease
inflammatory changes in the EOM and hypertrophy of orbital fat leading to ocular dysmotility, diplopia and proptosis
indications for corneal transplant
keratoconus
corneal scarring following infection or trauma
what is keratoconus
progressive thinning and bulging of the cornea into a conical shape
how can you prevent corneal graft rejection
long term use of topical corticosteroids
what is the surgical treatment for glaucoma
trabeculectomy
laser iridotomy
what are sight threatening complications of BRVO
macular oedema
rubeotic glaucoma
