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