Vitreous, peripheral retina, tears and detachments Flashcards
name 5 types of retinal tears
-u tears
-operculated tears
-retinal holes
-dialysis
-giant retinal tear
name 3 types of retinal detachments
-rhegmatogenous retinal detachments
-tractional retinal detachments
-exudative retinal detachments
what is the prevalence of retinal detachment?
0.3%
what is the most common type of retinal detachment?
rhegmatogenous retinal detachment (RRD)
where are most retinal breaks found and what percentage is it specifically?
(60%) found in the supero-
temporal retina
what is the definition of a retinal detachment?
separation of the NS retina from the underlying RPE
what are some good questions to ask a patient who has flashes and floaters?
-History of retinal detachments
-Whether they have diabetes - tractional retinal detachment from laser scar
-Whether they drive
give 2 stats on bilateral RD
-15% of patients with an RD in one eye get an RD in the 2nd eye
-Risk of bilateral RD increased to 25-30% in pts who have had
bilateral cataract extraction
what should you ask about Px history when assessing potential RD?
-flashes and floaters? distortion? curtain field defect?
-have they had a complicated cataract treatment, laser or trauma?
-connective tissue syndromes like diabetes? sickle cell retinopathy?
-past retinal problems or detachments?
what should you check for on slit lamp when looking for signs of RD?
-dilate the Px and look in the retrolental space for Shaefer’s sign
-check vitreous is clear and that there are no haemorrhages
give 4 features of chronic retinal detachment
-retinal thinning
-(high tide marks) demarcation lines
-intraretinal cysts
-wrinkling and folding as the eye is trying to repair itself
-proliferative vitreoretinopathy
why does it matter if the macula is on or off in an RD?
if macula is on they need surgery in 24 hrs so emergency but if not then it can be seen as urgent
what are the risk factors of RD?
-PVD
-A shadow or curtain in their vision could be a bleed suggesting vitreous haemorrhage
-reduced visual acuity
-artificial lens from a cataract can cause the vitreous to move more anteriorly causing increased risk of retinal detachment
-Sickle cell retinopathy can cause tractional retinal detachments
-blood thinners can make any haemorrhages worse
why is reducing VA in RD a serious concern?
as VA is only reduced if the macula is detached, it does not get worse if the macula is intact
what scan may you do if you are unsure whether there’s a vitreous haemorrhage?
a B scan
how can you treat retinal tears?
-Laser retinopexy where you create a chorioretinal scar which acts as a barrier around the brake to stop it from getting worse
-Cryotherapy which does the same thing as a laser just using cold
how can you treat a RD?
vitrectomy or pars plana vitrectomy
why may you get double vision after a RD has been treated
if a scleral buckle has been used to externally flatten the retina
when does a simple PVD become serious?
if it comes with a vitreous haemorrhage as it may have caused a retinal break. if the Px does not have diabetes and comes in with a vitreous haemorrhage then you have to assume there is a retinal break
what factors affect the success of a vitrectomy?
-how long the RD has been detached: the longer its been detached the lower the likelihood of a successful outcome
-whether the macula was on or off
-any underlying aetiology
what are the complications of retinal detachments?
*Primary failure of re-attachment
* Re-detachment
* Even if the retina is attached the VA remains poor
* Increased IOP: secondary glaucoma
* Usually temporary due to gas/ silicone oil or inflammation
* Ocular motility problems
* Refractive changes
* Cataract formation
what are the risk factors of PVD?
-myopia
-trauma
-inflammation
-collagen disorders
How does PVD happen?
- vitreous liquifies with age and empty spaces develop within it
- fluid can escape into the retro-hyaloid space which can therefor cause separation of the vitreous and retina
what are the signs of a PVD?
-weiss ring: shows where vitreous was attached to the optic nerve but has now detached
-wrinkly posterior hyaloid membrane
what should you do if you find PVD with vitreous haemorrhage?
HES referral
how do you treat a patient with simple PVD?
reassure them, give them SOS advice, review in 6/52 or
sooner if sx’s change
what is asterioid hyalosis?
degenerative process where calcium lipid complexes that are suspended throughout the collagen fibrils of the vitreous and float freely in the vitreous space
who is asteroid hyalosis most common in?
men
is asteroid hyalosis usually unilateral or bilateral?
unilateral
what is the only proven association of asteroid hyalosis?
age
what is synchysis scintillans?
a consequence of chronic vitrous haemorrhage, often the eye is blind where crystals made of cholesterol derived from plasma cells or degraded erythrocytes as yellow brown particles which sediment inferiorly when the eye is immobile
what is the difference in aetiology between asteroid hyalosis and snchysis scintillans?
-associated with aging, diabetes, hypertension
-associated with chronic disease or trauma linked to end stage retinal disorders
what is the difference in appearance between asteroid hyalosis and synchysis scintillans?
-yellow white suspended in the vitreous
-golden brown freely mobile and shimmering crystals which settle inferiorly when stationary
what is the difference in mobility between asteroid hyalosis and snchysis scintillans?
-particles are attached to the collagen framework and do not move freely
-particles move freely within the liquefied vitreous
what is the difference in symptoms between asteroid hyalosis and synchysis scintillans?
-mainly asymptomatic, rarely may cause mild visual distubances/ floaters
- can cause floaters or shimemring disturbances
what is the difference in vision impact between asteroid hyalosis and synchysis scintillans?
-rarely affects vision
-can cause noticeable vision disturbance when advanced
what is the difference in laterality between asteroid hyalosis and snchysis scintillans?
-typically unilateral while other is typically bilateral
what is the difference in management between asteroid hyalosis and snchysis scintillans?
there is no treatment for both
what is a rhegmatogenous retinal detachment?
where a retinal break and vitreoretinal traction allow the accumulation of liquified vitreous between the rpe and neurosensory retina separating them
what are some predisposing factors of RD?
-vitreous degeneration
-PVD
-predisposing lesions like lattice and snail track degenerations
-highly myopic eyes
-cataract surgery -pseudophakia/ aphakia
-history of rrd in fellow eye
-previous viral retinitis
why are highly myopic eyes at risk of RD?
-small round holes in chorioretinal atrophy
-macular holes
what are the signs of rrd on fundus photography?
-convex borders
-corrugated surface
-clear subretinal fluid
-bullae/ folds that undulate with eye movement
what are symptoms of rrd?
-flashes and floaters
-a curtain over the vision
what are the general signs of rrd?
-RAPD
-low IOP usually 5mmHg lower, very low may indicate choroidal detachment
-iritis
-shaefer’s sign
what are differentials of RD?
-degenerative retinoschisis
-choroidal detachment
-uveal effusion syndrome - rare
4 complications of scleral buckling?
-diplopia
-cystoid macular oedema
-elevated IOP
-choroidal detachment
what is the important thing to address in erd and trd
the underlying cause as that needs to be diagnosed to be treated
what is tractional retinal detachment?
where fibrosis/ fibrovascular proliferation leads to scar tissue that pulls off the retina
what is exudative retinal detachment?
where accumulation of subretinal fluid leads to detachment
what are the symptoms of tractional retinal detachment?
slow stable progress of visual defect
what are the signs of tractional retinal detatchment?
-RD has a concave configuration and breaks are absent
-retinal mobility is severely reduced and shifting fluid is absent
the SRF is more shallow than in rrd and never extends to ora serrata
-highest retinal elevation occurs at sites of vitreoretinal traction
-b scan shows incomplete PVD and relatively immobile retina
give 4 causes of tractional retinal detachment
-proliferative diabetic retinopathy
-retinopathy of prematurity
-penetrating trauma
-proliferative vitreoretinopathy
what are the symptoms of exudative rd
-floaters if associated with vitritis
-sudden development of a visual field defect which may develop rapidly
what are the signs of exudative RD?
-similar to rrd where config is convex but this time has a smooth surface
-detached retina is very mobile and shows the phenomenon of shifting fluid
-leopard spots consisting of subretinal pigment clumping after detachment has flattened
what are some causes/ risk factors of exudative rrd?
-uveitis
-tumours
-hypertensive retinopathy
name some retinal degenerations
-senile retinoschisis
-White without pressure
-White with pressure
-Dark without pressure
-Peripheral cystoid degeneration
-snowflake degeneration
-Pearl degeneration
Lattice degeneration
Snail track degeneration
Retinal tufts
Peripheral retinal tears
for lattice degeneration
-how common is it?
-signs?
-symptoms?
-complications?
-management?
-occurs in about 8% of the population, is present in 40% of eyes with RD
-signs include spindle shaped areas of retinal thinning, ‘snowflake’ lesions. sclerosed vessels forming a network of white lines
-small holes
-complications involve potential retinal (u) tears when PVD is present and atrophic holes
-asymptomatic cases need no treatment
what is a cystic retinal tuft?
-congenital abnormality
-contains small patch of oval elevated whitish lesion usually in equatorial or peripheral retina more commonly temporally
-can be a risk factor for horseshow tears
for senile retinoschisis, what is the prevelance
5% over the age of 20
what are symptoms of retinoschisis?
-usually asymptomatic
-occasionally any symptoms my arise from vitreous haemorrhage or progressive RD
what are the signs of retinoschisis?
-can appear as an exaggerated microcystoid degeneration with a smooth immobile dome-shaped elevation of the retina which can
-elevation is convex, smooth thin and immobile unlike rrd
-pigmented demarcation line which also shows RD
-lesion may progress circumferentially until entire periphery is involved
how do you manage retinoschisis?
-small peripheral RS does not need routine check
-large RS needs routine check
-retinopexy can be done if it seems to progress towards the fovea
what is the difference between white with pressure and white without pressure?
wwop is present without scleral indentation otherwise appearance is the same
what are the 5 types of retinal tears?
U tears
Operculated tears
Retinal holes
Dialysis
Giant retinal tear
What is a dialysis? what happens in it? what does it look like?
a circumferential tear along the ora serrata and is usually a consequence of blunt ocular trauma.
vitrous gel remains attached to the posterior margin
a large peripheral break with a regular rolled edge
how is a giant retinal tear different to a dialysis?
In dialysis, vitreous gel remains attached to the posterior margin whereas in a giant retinal tear, vitrous remains attached to the anterior margin of the break
do you treat atrophic lattice holes in the UK?
no
what is there none of in dialysis?
-break
-pvd
-retinal haemorrhage
what may trauma + vitreous haemorrhage make you suspicious of?
dialysis
how do you manage dialysis?
scleral buckle NOT vitrectomy as it creates the same effect without affecting the anatomy as it’s not necessary.
