Retina Flashcards
what should be described when examining the optic disc
cup
colour
contour
vessels
what colour should the optic disc be
pale pink
it is more pale in optic atrophy
optic atrophy - disc appears pale
describe the contour of the optic disc
- oval
- larger
- blurred margins
oval in astigmatism
may appear larger in myopic eyes
blurred margins in papilloedema and optic neuritis
normal arterial:venous width ratio
2:3
central retinal vein occlusion - venous engorgment
pale retina and cherry red spot on macula - central retinal artery occlusion
how much of disc diameter should the optic cup occupy
a third
cup widening and deepening
glaucoma
is there pain on retinal detachment
no, the retina has only photoreceptors
retinal detachment
holes/tears in retina allow fluid to accumulate and separate the sensory retina (inner layer) from the pigmented retinal epithelium
what type of trauma tyically causes retinal detachment
blunt trauma
how long is the typical history on presentation
around 2 weeks
rhegmatogenous retinal detachment
occurs when a retinal tear leads to fluid accumulation with a separation of the neurosensory retina from the underlying retinal pigmented epithelium
most common type
who is more prone to retinal detachment
myopic eyes
the higher the myopia, the greater the risk
how does retinal detachment present
4 F’s
floaters, flashes, field loss and fall in acuity (painless and may be perceived as a curtain falling over the vision - lasting >5 minutes)
what is seen on ophthalmoscopy of a retinal detachment
grey opalescent retina, ballooning forwards
