Gradual loss of vision

Question 1

causes of gradual visual loss (8)

Answer 1

cataracts
diabetic retinopathy
glaucoma
HTN
slow retinal detachment
macular degeneration
optic atrophy
retinitis pigmentosa

Question 2

Choroiditis definition and causes (5)

Answer 2

infection that can>granulomatous reaction caused by:

• toxoplasmosis
• toxocara
• TB
• sarcoidosis

Question 3

presentation of choroiditis (4)

Answer 3

floating black spots
pain/redness
blurring of vision
photophobia

Question 4

Ix in choroiditis (3)

Answer 4

CXR
Mantoux (tuberculin)
serology

Question 5

Fundoscopy in choroiditis (4)

Answer 5

raised white-grey patch
choroidal opacities
white cells in anterior chamber
later, choroido-retinal scars form which appear as white patches and are asymptomatic unless they affect the macula

Question 6

epidemiology, fundoscopy and complication of choroid melanomas

Answer 6

most common ocular malignancy
fundoscopy shows mottled grey/black patch
there is retinal detachment over the melanoma

Question 7

Rx of choroid melanomas (5)

Answer 7

enucleation
plaque/local radiotherapy
photocoagulation
trans-pupillary thermotherapy
micro-surgical resection

Question 8

RFs for age-related macular degeneration (7)

Answer 8

hypermetropia
female
caucasian
blue eyes
low B12
high cumulative light exposure
genesd

Question 9

Features of macula in ARMD (5)

Answer 9

pigment
drusen-fatty deposits
optic disc is irregular, lumpy and yellow
absent optic cup
sometimes there is bleeding

Question 10

Features of dry(non-neovascular) ARMD (3)

Answer 10

90% of ARMD
mainly drusen and degenerative changes at macula
slow progression

Question 11

Fundoscopy of wet ARMD (3)

Answer 11

retinal pigment epithelium thickens
drusen develops
new choroidal vessels grow from choroid>neurosensory retina and cause leakage of blood.

Question 12

key clinical features of wet ARMD (2)

Answer 12

rapid deterioration of CENTRAL vision-may only take a few wks.

distorted vision

Question 13

Ix or wet ARMD (2)

Answer 13

fundoscopy shows fluid exudation and localised detachment of pigment

fluorescin angiography allows visualisation of the extent of neovascularisation

Question 14

Rx of wet ARMD

Answer 14

regular monitoring w. fluorescin angiography
intravitreal anti-VEGF: bevacizumab/ranalizumab
photocoagulation
intravitreal steroids as an adjunct-triamcinolone

Question 15

Other measures in wet ARMD (3)

Answer 15

screening once signs have been identified e.g. Amsler grid
visual aids
diet:leafy green vegetables, omega 3, zinc, vit B+C+E, beta carotene(avoid in smokers), lutein

Question 16

Presentation, aetiology, fundoscopy and Rx of Stargardt macular degeneration (4)

Answer 16

gradual visual loss in teenagers
assoc. w. many genetic mutations.
fundoscopy shows prominent yellow flecks
Rx w. embyronic stem cells

Question 17

Pathogenesis and features of tobacco-alcohol amblyopia (4)

Answer 17

cyanide radicals from combined smoking and alcohol excess lead to optical atrophy, loss of red-green discrimination and scotoma.

Question 18

Categories of cataracts (5)

Answer 18

immature-red reflex still present
dense-no red reflex+unable to visualise fundus
nuclear sclerotic-change in refractive index w. age
anterior/posterior polar cataracts-localised, commonly inherited and lie in visual axis
subcapsular opacities (e.g. from steroids) are just deep to the lens capsule

Question 19

RFs for cataracts (13)

Answer 19

age/UV exposure
hypocalcaemia
turner's
galactosaemia
steroid use
infection-congenital rubella
dystrophia myotonica (cataracts, male pattern baldness, heart block and locking muscles)
DM
chronic anterior uveitis
down's
irradation
touching lens during surgery
high myopia

Question 20

Presentation of cataracts (5)

Answer 20

blurred vision
frequent change in specs prescription
dazzle
monocular diplopia
vision may improve w. pinholing

Question 21

fundoscopy and important Ix at Dx of cataracts

Answer 21

black dot in middle of red reflex>cataract obscuring path of light to the retina

do fasting blood glucose at Dx

Question 22

surgical Mx of catarcts including pre and post-op (6)

Answer 22

pre: ocular biometry to measure curvature of cornea and length of eye

during:

• phacoemulsion: break down and aspirate lens
• insert prosthetic lens

post:

• may have Sx of imbalance
• lens can’t accomodate => new reading glasses needed
• anti-inflammatory eye drops and Abx needed for 4-6wks

Question 23

complications of cataracts surgery (6)

Answer 23

lens thickening
irritation
astigmatism becomes more noticeable
anterior uveitis 
intra-ocular lens dislocation
rarely:vitreous haemorrhage, glaucoma and endopthalmitis

Question 24

Features of intra-ocular lens dislocation (6)

Answer 24

decreased vision
diplopia
halos in vision
streaks of light in vision
lens glare
photosensitivity

Question 25

Causes of intra-ocular lens dislocation (5)

Answer 25

Marfan's (upwards)
EDS
trauma
uveal tumours
homocysteinuria (downwards)

Question 26

Mx of cataracts at birth and complications

Answer 26

correct by 6wks during latent visual period

otherwise risk deprivation amblyopia (lazy optic nerve)

Question 27

pathogenesis of glaucoma (2)

Answer 27

raised IOP>optic neuropathy

death of retinal ganglion cells and their nerve axons

Question 28

Definition of glaucoma (2)

Answer 28

visual field defects in =/>3 areas
cup:disc ratio>0.5
(raised IOP not part of criteria)

Question 29

pattern of visual loss in glaucoma (2)

Answer 29

nasal and superior fields lost first

temporal field lost last

Question 30

high risk groups for glaucoma (4)

Answer 30

> 35yrs w. +ve 1st degree FHx
Afro Caribbean
myopia
DM/thyroid eye disease

Question 31

Screening tests for glaucoma (3)

Answer 31

multiple stimulus static visual field testing
documenting optic cupping
measuring IOP via tonometry (10-20 normal)
(raised IOP warrants annual screening)

Question 32

Rx of glaucoma (6)

Answer 32

prostaglandin analogues 1st line: latanoprost, travoprost (increased uveoscleral outflow)

beta-blockers 2nd line: timolol, betaxol (decreased aqueous production)

alpha adrenergic agonists: brimonidine, apraclonidine (increased outflow+decreased production)

carbonic anhydrase inhibitors: acetazolamide, dorzolamide, brinzolamide (decreased production)

Miotics: pilocarpine (decreased resistance to outflow)

sympathomimetics: dipivefrine
surgery: trabeculectomy for refractory cases

Question 33

definition and fundoscopy of optic atrophy (2)

Answer 33

death of retinal ganglionic cells which make up optic nerve

fundoscopy shows brighter, well-demarcated optic disc

Question 34

Causes of optic atrophy (6)

Answer 34

raised IOP: glaucoma
inflammation: optic neuritis, syphilis
external pressure: intra-orbital tumours, Paget’s affecting skull
ischaemia: centra retinal artery occlusion
hereditary: leber’s optic atrophy, freidrich’s ataxia
retinal damage: choroiditis, cerebrolmacular degeneration, retinitis pigmentosa