Vitreo-retinal: Retinal Detachment Flashcards
What are floaters and photopsia
Floaters
Photopsia (flashing light)
What are causes of floaters
Blood - Vitreous haemorrhage
Cells - Anterior,intermediate, posterior uveitis
Collapsed vitreous - high myopia, old age
What are causes of photopsia and why does it occur
Retinal tear
Retinal detachment
Vitreous detachment
Mechanical stimulation of photoreceptors in retina
What is the significance of floaters/photopsia
Common - esp w old age and high myopia
New flurry of floaters/photopsia - requires urgent referral
What is Posterior Vitreous Detachment
Vitreous gel separates from posterior retina
What are causes of PVD
Trauma
Old age - fluid collects bw retina + vitreous membrane
High myopia
What are clinical features of PVD
Floaters - ‘cobweb’, due to haemorrhage or collapsed vitreous
Photopsia
What is the natural history of floaters
Common
Majority self-limiting + low risk of retinal detachment
Acute PVD with flurry of floaters - risk of rhegmatogenous retinal detachment
Management of PVD
Slit-lamp examination - look for retinal tear
No retinal tear: reassurance
Retinal tear: Laser Retinopexy - to seal retinal tear, prevent retinal detachment
What is retinal detachment
Retina separates from retinal pigment epithelium due to sub-retinal fluid
When retina separates from blood supply, photoreceptors slowly degenerate, becoming permanently non-functional
What are the types of retinal detachment
Macula ‘on’
Macula ‘off’
What are the causes of retinal detachment
Rhegmatogenous
Exudative
Tractional
What is rhegmatogenous RD
Retinal tear causes flow of vitreous into sub-retinal space
What is exudative RD
Inflammatory conditions cause exudation of fluid from leaky vessels into sub-retinal space
What is tractional RD
Fibrovascular membranes growing abnormally in vitreous contract and pull retina away from RPE
e.g. proliferative diabetic retinopathy
What are clinical features of RD
Photopsia, Floaters
Loss of vision - gradual, begin as shadow in peripheral field, ‘curtain coming upwards’
Blurred vision - Macula ‘off’
Reduced VA: in macula ‘off’, or in bullous RD in front of macula
Tobacco dust - sign of retinal tear: red cells/RPE cells in vitreous, migrated from retina through tear
What is the management of RD
Vitreo-retinal surgery:
Rhegmatogenous: laser, cryotherapy, vitrectomy
Exudative: treat the cause
Tractional: relieve traction
Oil or Gas + patient positioning post-operatively: allows compression of retina while awaiting effects of surgery (1wk to take effect)
What is prognosis of RD
Macula on: requires urgent surgery - allows good recovery of vision
Superior RD: requires urgent surgery - gravity pulls retina down to macula, risk of macular detachment
Macula off: poor recovery of vision
