Eye Flashcards
(44 cards)
List some systemic diseases that result in eye problems
- diabetes
- hypertension
- carotid disease
- autoimmune diseases (ankylosing spond, Crohn’s/UC, HIV, sarcoidosis)
- TB
List some causes of loss of red reflex
- retinal blastoma
- congenital cataracts
Best drug to use for pupil dilation + its MoA
Tropicamide. Anti-ach
lasts 2-4h. Don’t use atropine as effects last about 1 week
3 C’s to look for in optic disc exam
- colour
- cup
- contour
The rods/cones are found in the macula/peripheral retina
Cones: macula
Rods: peripheral retina
Causes of blurred optic disc
inflammation/ infiltration causing swelling of CN2 fibres
Causes of optic disc cupping
Advanced glaucoma (loss of nerve fibres)
What is RAPD/Marcus Gunn pupil
Defect in direct response (damaged CN2)
Causes of RAPD
- Optic neuritis
- Ischaemic optic disease/ retinal disease
- Severe glaucoma causing trauma to CN2
- Direct CN2 damage (trauma, radiation, tumour)
- Retinal detachment
- Very severe macular degeneration
- Retinal infection (CMV, herpes)
What is aniscoria. Is this alarming
Asymmetrical pupil size
normal variant in 1/5 population. Dangerous if manifestation of Horner’s or CN3 damage
What is Adie’s pupil. What causes it
Absent/slow response to light (direct + consensual response)
Denervation in postganglionic parasym N. Benign.
What is Argyll Robertson pupil. Is it alarming.
Pupils constrict with accommodation, but WON’T constrict to light (usually both pupils involved)
Hallmark of tertiary neurosyphilis
What are the 3 hallmarks of Horner’s syndrome
ptosis
miosis
anhydrosis
Causes of Horner’s syndrome
- Carotid artery dissection
- Pancoast tumours, nasopharyngeal tumours
- Lymphoproliferative disorders
- Brachial plexus injury
- Cavernosus sinus thrombosis
- Fibromuscular dysplasia
Describe 3 steps in pathology of diabetic retinopathy
- Breakdown of capillary tight junctions leading to leakage of blood, proteins
- Loss of rigidity of vessel way leading to micro-anurysms.
- Capillary occlusion leading to ischaemia, release of VEGF leading to formation of new blood vessels (proliferative stage)
Negative/red numbers on fundoscope focus on items that area near/far
Negative/red: far
Positive/green: near
What does visual acuity refer to
Central vision for corrected eyesight (with glasses)
How to do corneal reflection test
Shine light in middle of patient’s nose with their eyes looking at the torch
How to do cover reflection test
Cover 1 eye, look at other eye
How to do alternate cover test
Cover each eye for about 1s, then uncover that eye and look at it
How to assess ocular movements
- Ask patient to follow the light whilst keeping head still in the primary position
- Move torch in the direction of action of each muscle in turn, returning to the primary position after each excursion.
What is manifest strabismus/ heterotropia
Condition in which one or other visual axis is not directed towards the fixation point
What is latent strabismus/ heterophoria
Tendency for eyes to want to drift
Both visual axis are directed towards same fixation point but deviate on dissociation (when 1 eye is covered)
Define
o Esotropia
o Exotropia
o Hypotropia
o Hypertropia
o Esotropia: convergent squint
o Exotropia: divergent squint
o Hypotropia: eye goes down
o Hypertropia: eye goes up
