Gradual Visual Loss

Question 1

how may gradual visual loss present

Answer 1

often early with reduced visual acuity or late with decreased field

Question 2

typical causes

Answer 2

cataract

Dry ARMD

refractive error

glaucoma (open-angle)

diabetic retinopathy

hypertension

Question 3

cataract

Answer 3

any opacity in the lens is called a cataract

Question 4

risk factors for cataract development

Answer 4

• Most cataracts are age related
• In children, many are genetic
• Cataracts occur early in: DM, steroid use, high myopia a

Question 5

cataracts in DM

Answer 5

• Develop earlier in people with DM. Normoglycaemia may reverse.

Question 6

what must be measured when a cataract is found

Answer 6

fasting plasma glucose to exclude DM

Question 7

what is the 1y cause of preventable blindness worldwide

Answer 7

cataracts

Question 8

red reflex in cataracts

Answer 8

• in immature cataracts the RR still appears
• if the cataract is dense there is no RR

Question 9

what are cataracts classified by

Answer 9

lens appearance

Question 10

nuclear cataracts

Answer 10

• changes the lens refractive index and is common in old age
• gradual clouding of central portion of lens - the ‘nucleus’

Question 11

how do nuclear cataracts often occur, adn what is a characteristic sign of this

Answer 11

blunt trauma - stellate morphology

Question 12

subcapsular cataract

Answer 12

just deep to lens capsule in the visual axis

Question 13

what are subcapsular cataracts often associated with

Answer 13

• STEROID use, DM and hypermetropia
• allopurinol use may be indicated

Question 14

anterior and posterior polar cataracts

Answer 14

Anterior and posterior polar cataracts are localized, commonly inherited and lie in the visual axis. Round mass in the central portion of the lens.

Question 15

polychromatic (Christmas tree) cataracts

Answer 15

consist of highly reflective, iridescent corneal crystals of different colours

Question 16

cortical cataract

Answer 16

start in the periphery and move into centre

Question 17

presentation of a cataract

Answer 17

• blurred vision, unable to be corrected by glasses
• halos surrounding lights

Question 18

how do unilateral cataracts present

Answer 18

often unnoticed, loss of stereopsis (depth perception) affects distance judgement

Question 19

how do bilateral cataracts present

Answer 19

gradual loss of vision, dazzle (especially in bright light), monocular diploplia

Question 20

how do cataracts present in children

Answer 20

squint, loss of binocular function or a white pupil or nystagmus/amblyopia

Question 21

management of cataracts

Answer 21

surgical removal with intra-ocular lens if the patient is symptomatic

Question 22

dry ARMD features

Answer 22

called dry as there is no fluid in the macula

central vision is missing (‘scotoma’)

drusen in macula and degenerative changes (atrophic patches ) in the macula

Question 23

drusen

Answer 23

• signify optic nerve head axonal degeneration - abnormal axonal metabolism leads to intracellular mitochondrial calcification
• some axons rupture and mitochondria are extruded into the extra-cellular space below RPE
• calcium is deposited

Question 24

progression of dry ARMD

Answer 24

progresses slowly, may progress to wet

Question 25

management of dry ARMD

Answer 25

there is no cure, treatment is supportive with low vision aids eg magnifiers

Question 26

Question 27

Answer 27

polychromatic cataract