DIS - Retinal Detachment - Week 8 Flashcards
Define retinal detachment, including the layers affected.
Separation/cleavage between the photoreceptors and the RPE
What does retinal detachment result in the opening of? what accummulates?
Results in the reopening of the subretinal space and accumulation of fluid in this space
What happens to the subretinal space during embryonic development?
It closes as optic vesicle invaginates to form the optic cup
Is retinal detachment sight threatening? Is it considered an ocular emergency?
Yes
List the two forms of retinal detachment.
Rhegmatogenous RD
Non-rhegmatogenous RD
Define rhegmatogenous retinal detachment. What is it held open by? What does it facilitate the spread of and where?
Results from a retinal tear/hole
Break is held open by traction
Facilitates the spread of fluid from the liquefied vitreous to the subretinal space
Where are breaks more likely with rhegmatogenous retinal detachment?
More likely within a zone of degeneration
What forms around the hole/tear in rhegmatogenous retinal detachment? What happens to this and due to what(2)?
Localised detachment (cuff)
-usually spreads towards the macula, usually by subretinal fluid
What is meant by secondary non-rhegmatogenous retinal detachment? What can it be caused by?
Retina is pulled from the RPE in the absence of a tear
-caused by major internal disturbance (trauma)
What is meant by tractional non-rhegmatogenous retinal detachment? List three causes.
Shrinkage of fibrovascular vitroretinal membrane
-diabetes, CRVO, BRVO
What is meant by exudative non-rhegmatogenous retinal detachment? What does it occur subsequent to and what is the pathogenesis?
Subsequent to a damaged RPE which permits leakage from the choroid into the subretinal space
List 5 possible causes of exudative non-rhegmatogenous retinal detachment.
AMD
CSR
Choroidal tumour
Intraocular inflammation
Toxaemia of pregnancy
What happens to the incidence of retinal detachment with age? Which age has the highest incidence?
Increases with age, most in mid-50s
Is retinal detachment more common in males, females, or equal?
More in males
Compare the incidence of retinal detachment among caucasians vs asians.
Caucasians»_space; asians
Which age group does trauma related rhegmatogenous retinal detachment tend to occur?
<50
Is there a genetic component to rhegmatogenous retinal detachment?
Yes, 2.6x greater risk if relative diagnosed
List four genetic conditions associated with rhegmatogenous retinal detachment.
Syndromic myopia
Wagner syndrome
Stickler syndrome
Erosive retinopathy
Does myopia increase or decrease the risk of retinal detachment?
Increase
Does cataract surgery increase or decrease the risk of retinal detachment? Explain.
Increases linearly over time due to vitreous structure collapse
-decreased support
Is a retinal hole considered safe once it has pigmented?
Yes
List three abnormal vitreous adhesions that are risk factors for retinal detachment.
Meridional folds
Enclosed oral bays
Granular tissue
Describe how posterior vitreous detachment is a risk factor for retinal detachment, noting which type it can cause (5).
The collapsing vitreous exerts mechanical pull on the retina, causing traction, resulting in haemorrhage or tears -> rhegmatogenous retinal detachment
Summarise the risk factors for retinal detachment (4).
Fellow eye has RD
Positive family ocular history
High myopia
Past cataract surgery
List retinal degenerations that have a high incidence of retinal detachment. Note the most important one first.
Lattice degeneration
Snail track
Snowflakes
Cystoid degeneration
Retinoschisis
White without pressure
Note which of the following degerations have an association with retinal detachment:
Pavingstone
Reticular
Peripheral drusen
None
How should lattice degenerations be assessed when suspecting retinal detachment? Include a comment on tears within the degeneration.
Search for tears/holes near the edge or outside of the lattice
Those inside the lattice are often pigmented over and safe
Is rhegmatogenous retinal detachment symptomatic?
Yes, 93% first time will have symptoms
List three symptoms associated with rhegmatogenous retinal detachment. Note the most common first.
Loss of vision/blurry vision
Shadows
New floaters
What is a strong indicator of a retinal tear?
Sudden onset (<6/52)
-most present within a week
What is essential for individuals with fewer symptoms on repeat rhegmatogenous retinal detachment?
Regular reviews
List four causes of sudden increases in floaters or new floaters.
Haemorrhage
Retinal tissue
Vitreous floaters
Pigment
What is photopsia caused by and how do patients perceive it? How long do they last and where in the visual field is it projected relative to the retina? What can initiate/worsen it?
Mechanical stimulation of the photoreceptors by traction/pressure
A yellow, white, silver arc/lightning bolt or vertical flash
Frequent but momentary
Projected into the opposite visual field
Worsened/initiated by head movement
Does photopsia recur in the same position?
Yes
What is metamorphopsia and why does it occur?
Distorted vision
-caused by the retina not being flat
What is a pre-retinal haemorrhage and what is it often near?
Vitreous traction tears retinal blood vessels
Often near retinal tears