Opthalmology Flashcards
Types of Glaucoma
Open angle
Acute angle closure glaucoma
Normal pressure glaucomaG
Glaucoma is an
Damage to the optic disc, often due to an increase in IOP
Open angle glaucoma
Most common
Usually without symptoms - can slowly damage the eye without the person becoming aware of it
Often aqueous fluuid can not flow through the trabecular meshwork and drain properly
Acute angle-closure glaucoma
Sudden, sever pain in the eye, often iwth immediate disturbance of vision, such as coloured rings around lights, N&V.
Complete blockage of optic flow.
Surgical techniques to treat glaucoma
Laser treatment - improve flow of aqueous fluid, or destroy parts of ciliary body.
Topical - B blocker, A agonist
Retinal detachment process
Retinal tear or hole develops - fluid leaks between retina & choroid - detaches
Retinal detachment symptoms
Sudden onset of floaters and flashes, vision loss curtain
Cataracts
Lens becomes cloudy - images can’t focus properly
Cataracts treatment
Phacoemulsification & Surgery - removal and replacement of lens (intraocular lens implant)
Blind definition
<10 degrees central vision or vision <3/60
Low vision definition
< 20 degrees central vision or vision 6/18-3/60
worldwide leading cause of blindness
Cataracts
NZ leading causes of blindness
Macular degeneration (48%), glaucoma (16%), cataract (11%)
Beneath the retina is the
Choroid
Fovea
Where focus - super concentrated cones?
Optic disc
Where optic nerve enters
Optic disc look at
Colour, cup to disc ratio, contour
+ red reflex, retinal vessels
Cataracts symptoms
Painless, gradual loss of vision
Glare
Refractive change
Key issue = driving
Cataracts risk factors
AGE AGE AGE
Smoking, diabetes (possible ascertainment bias), steroid use
Cataracts examination
Red reflex absent
Fundoscopy - normal if can see through lens
Glaucoma important history
family history
Glaucoma symptoms
None until too late
Glaucoma Fundoscopy
Cup vertical elongation, cup to disc ratio abnormalities
Bayonetting, lamina cribosa of optic disc.
ISNT - thinning of rim in ISNT order
Risk Factors macular degeneration
Age, FHx, Caucasian, Female
Wet ARMD treatment
Intravitreal anti-VEGF monoclonal antibodies - monthly
injection
2/3 chance improvement
90% remains same
Eye examination
-Visual acuity (snellen chart, reading test).
-Pupils equal, round, reactive to light and accomodation
- Visual fields by confrontation
Angle, intra-ocular pressure, dilate pupils (1% tropicamide)
Slit lamp - anterior segment,
Fundus - opthalmoscope
6/6-2
Reads the 6/6 line but gets two letters wrong
How many letters do you need to get right to get the line snellen
3 (out of 5)
- however many wrong
Snellen chart which number stays the same
Numerator
Most common preventable blindness nz
Glaucoma
Cup vertical elongation indicates
Glaucoma
Bayonetting indicates
Glaucoma
Diabetes mellitus fundoscopy - proliferative vs non proliferative
Proliferative - vacsular proliferation, neovascularisation of optic disc, blot haemorrhage,
Hard exudates & microaneurysm, dilated veins (non proliferative)
*correction everything on both just neovascularistation in
Proliferative diabetic retinopathy treat with
Better diabetic control
Pan retinal photocoagulation
Hypertension macular
Macular star
Dry age related macular degeneration fundoscopy
ARMD
Hyperpigmentation of the macular, drucen
Bitemporal hemianopia
Optic chiasm
Homonymous hemianopia
Optic tract
Homonymous hemianopia with macular sparing
Occipital lobe
Quadrantanopia
Google this more
20 ft in m
6m
if acuity improves with pinhole
Refractive error
If acuity worsens with pinhole
Macular degeneration or cataracts
Refractive error
Shape of eye keeps light from focusing correctly on your retina
Treatment for cataracts
Phacoemulsification & intraocular lens implant
Glaucoma definition
Damage to the optic disc, often with raised intraocular pressure
Glaucoma treatment
Medical - topical - BB, prostaglanding analogues, carbonic anhydrase inhibitors
Systemic - carbonic anhydrase inhibitors
Surgical
Macular degeneration fundoscopy
Dry - Hyperpigmentation, drusen of macular
Wet - disciform - big black grey ring, subretinal fluid, haemorrhage, fibrosis
Dry mac degen
Gradually deteriorating vision, painless, one eye
Wet mac degen
Sudden onset blurred vision, painless, one eye
Scotoma
