Posterior Flashcards
What is the pathogenesis of retinal vein occlusion
compression at AV crossings –> degenerative venous changes –> hypercoagubility
What are the risk factors of retinal vein occlusion? (9)
hypertension hyperlipidemia diabetes CVD increased IOP/glaucoma smoking high BMI CT disorders/sarcoidosis/lupus vasculitis
Symptoms of BRVO? (5)
may be asymptomatic onset often in morning transient vision loss metamorphopsia VF defects
Signs of acute BRVO (6)
located in one quadrant flame/dot-blot haemorrhages CW spots dilated, tortuous veins oedema ON swelling/hyperaemia
Signs of chronic BRVO (2)
venous collateral formation
vascular sheathing
What modalities should you use to investigate BRVO? (2)
Fluorescein angiography
OCT
BRVO complications (2)
macula oedema
vitreous haemorrhage
BRVO are urgently referred if acute and semi-urgently if chronic for a systemic work-up and consideration of what types of treatment? (3)
laser
intravitreal steroid
anti-VEGF Tx
What is the optometrists role in managing BRVO other than referral?
monitoring for signs of NV and assoc complications
What are the clinical features of CRVO? (7)
intra-retinal haemorrhage (all quadrants) venous engorgement and tortuosity optic disc swelling CW spots CMO sudden painless loss of vision presenting VA reduced
Pathogenesis of CRVO?
Compression of CRV at lamina cribosa either by thrombus or CRA
Ischaemic vs non-ischaemic CRVO
Ischaemic
- VA <6/60
- marked RAPD
- optic nerve swelling
- severe venous tortuosity
- risk of developing retinal and iris NV
Non-ischaemic
- more common
- VA >6/60
- minimal RAPD
- may convert to ischaemic
CRVO management? (4)
monitoring monthly for 1 year
thrombolytics
Laser chorioretinal anastomosis (L-CRA)
pan retinal photocoagulation
*possibly intra-vitreal anti-VEGFs
A person with CRVO has a better outcome when
present early and treated early
CRAO symptoms (3)
- painless vision loss over several seconds
- possible Hx of amaurosis fugax
- vision significantly reduced (<6/120) unless cilioretinal artery present
CRAO signs (4)
- VA <6/120 and RAPD in affected eye
- Within first few minutes retina may look normal
- ischaemic whitening of retina resulting in cherry-red spot at macula
- retinal arteriole thinning and attenuation with possible segmentation of blood flow
What is the level of urgency for CRAO?
ophthalmic emergency - urgent referral
Management for CRAO? (7)
- emergency referral
- digital ocular massage or with gonio
- reduction of IOP by paracentesis or pharmaceutically
- assessment of risk of GCA
- control of systemic disease (HT, diabetes, hyperchol)
- assessment of carotid and cardiac disease as source of emboli
- use of aspirin or warfarin
BRAO can occur secondary to what two things?
emboli
inflammation
Over 90% of BRAOs involve arteries in which area?
temporal retinal arteries
BRAO symptoms (2)
- acute, unilateral, painless loss of vision over several seconds
- visual field defect may be noticed
BRAO signs (4)
- VA <6/12 affected eye
- initially fundus looks normal within first few mins
- localised ishaemic whitening of retina in area fed by arteriole
- retinal arteriole thinning and attenuation with possible segmentation of blood flow
Management of BRAO (4)
- referral for assessment of systemic associations
- control of systemic disease as for CRAO
- assessment for carotid and cardiac disease as for CRAO
- majority of Px achieve 6/12 or better with conservative Tx
Which is more common: BRVO or CRVO?
BRVO
BRAO level of urgency?
urgent referral
Optic disc drusen is believed to be buried or superficial _______ material as a biproduct from which cells?
hyaline-like astrocyte
Optic disc drusen can often cause what two signs?
field defects
choroidal neovascular membranes
What tests are done for a definitive Dx of optic disc drusen? (2)
B-scan and FA
Optic disc drusen are associated with what condition?
Pseudoxanthoma elasticum
The most important thing with optic disc drusen is?
to rule out other conditions which involve the disc
Optic disc colobomas are typically located where and accompanies a field defect located where?
inferior nasal
superior
Optic disc and chorioretinal colobomas can develop into what?
serous macular detachment
Morning glory anomaly is what?
variant of ONH coloboma
With morning glory anomaly the disc is deeply escavated with what sort of tissue at the base?
glial
Optic disc pits are what?
atypical coloboma of ONH
What is management of Px with optic disc pit?
monitor carefully including home Amsler
With posterior coloboma conditions we need to be aware that these can develop what?
serous maculopathy
Which condition demonstrates the “double ring sign”
optic nerve head hypoplasia
Optic nerve head hypoplasia results in?
loss of NFL with variable VF defects
Which condition is associated with maternal infection or drug abuse, fetal alcohol syndrome, gestational diabetes and brain malformations?
optic nerve head hypoplasia
What condition can make the disc look raised with indistinct margins and have anomalous vascular branching patterns (not papilloedema, papillitis)
small optic disc
Which condition is characterised by an enlarged ONH with large cupping with the lamina often visible (DDx with glaucomatous cupping)
megalopapilla
High survival rates of retinoblastoma are associated with?
early detection
Retinoblastoma signs? (5)
- White mass projecting forwards or backwards from retina
- leukocoria
- strabismus
- intraocular inflammation
- increased IOP
Tx of retinoblastoma? (4)
- cryotherapy
- thermotherapy
- radiation therapy
- enucleation
What condition is characterised by a retrolental mass of persistent embryonic hyaloid system and primary vitreous?
persistent hyperplastic primary vitreous
Retinopathy of prematurity is characterised by?
abnormal retinal vasculature in premature infants and/or low birth wt
ROP can be associated with?
supplemental oxygen
What are the five stages of ROP?
Stage 1 - white line at demarcation of avascular zone
Stage 2 - development of ridge and abnormal vessels
Stage 3 - fibrovascular proliferation
Stage 4 - contraction of fibrovascular tissue and RD
Stage 5 - complete RD
WARP CD
What is this condition?
- single or grouped usually unilateral
- flat, well demarcated, dark
- tend to depigment over time
- can be grouped (bear tracks)
- can be atypical and associated with colon polyps
congenital hypertrophy of the RPE
When there are multiple, large, bilateral CHRPEs affecting several quadrants, what other condition needs to be considered?
familial adenomatous polyposis
What are myelinated nerve fibres?
persistent myelination of axons anterior to lamina cribosa
Which condition causes the fundus to later develop granularity pigmentary changes and vessel attenuation with other signs: sluggish pupils, nystagmus, strabismus, cataract, KC, abnormal ERG?
leber’s congenital amaurosis
Splitting of the NFL from retina in periphery is called?
retinoschisis
What condition has hypoplasia of ONH and/or fovea with varying levels of reduced VA?
albinism
varying degrees of amelanosis is due to varying levels of what?
tyrosinase
What is management of albinism? (2)
- control glare and photophobia
- low vision aids
When examining a Px with albinism what should you keep in mind?
don’t prolong fundoscopy
What is the condition when you are born with no fovea?
hypoplastic fovea
What is tilted disc syndrome?
ONH appears rotated about its axis
Tilted disc syndrome signs? (4)
- oval shape disc
- scleral crescent
- myopic astigmatism common
- bi-temporal VF defects possible
What is obliquely inserted disc?
ONH inserts through scleral canal at an oblique angle
Obliquely inserted disc signs (4)
- elevated nasally, buried temporally
- function normal (usually)
- often hyperopic
- usually bilateral
Glial remnants are common in premature babies and protrude into the vitreal cavity and they are remnants of what?
embryonic hyaloid artery and related glial tissue
Toxoplasmosis scars are _________ in location, focal, with pigmented borders and can re-activate causing _____
chorio-retinal
retinitis
Risk factors for ARMD (3)
- Age
- Smoking
- Race - higher incidence in Caucasians
Classification of ARMD including proportion of cases
atrophic - dry - 80-90%
exudative - wet - 10-20%
In atrophic AMD, atrophy of what three cell types occurs?
photoreceptors
RPE
choriocapillaris
What test is essential for diagnosis of ARMD?
OCT
Hard drusen are _____ in size (___um), discrete and usually does not necessarily signify ARMD
small
<50-60um
Soft drusen are _____ in size (___)um, have indistinct margins and is more associated with ARMD
larger
=/>60 microns
Soft drusen can develop and become two things which are?
confluent drusen
calcified
Drusen are accummulation of waste products from which layer of the PRs and are found in between what layers?
Outer segment
Bruch’s and RPE
Generally it is agreed that a Px has AMD after what is compromised? This occurs due to the ___ no longer being intact and causing damage to the PRs at the macula
BCVA
Inner segment
reflective deposits between RPE and retina found in the peripheral retina often seen in association with drusen and a risk factor for ARMD are called?
reticular pseudodrusen
Symptoms of atrophic ARMD? (4)
- slowly decreasing BCVA
- deepening central scotoma
- usually bilateral but asymptomatic
- positive Amsler grid findings
Signs of atrophic ARMD (4)
- RPE atrophy and hyperpigmentation
- broadening of atrophy with progression
- visible choroidal vessels
- drusen and mottling
Use of fluorescein angiography with atrophic AMD shows what two things?
hyperfluorescence in areas of RPE atrophy
hyper or hypo fluorescence of drusen
Tx of atrophic ARMD? (3) ish
- none effective
- nutritional supplements may slow progression
- low vision aids when BCVA severely affected
Exudative ARMD signs? (4)
- often soft, confluent drusen
- serous maculopathy (sometimes with hard exudates)
- Sub-RPE or sub-retinal CNV
- Sub-retinal haemorrhage
Exudative ARMD symptoms (3)
- increased blurred vision
- metamorphopsia
- vision loss can be sudden due to sub-macular haemorrhage
Suspected cases of exudative ARMD should be urgently referred for what test which determines the exact location in relation to the retina?
FA
Exudative ARMD Tx starting from historical to current main Tx (3)
- Photodynamic therapy - inject VISUDYNE and laser applied to CNV
- Argon laser photocoagulation - destroys CNV however cannot be undertaken if CNV near or under macula. 50% recurrence rate.
- VEGF blockers
What are the 3 current VEGF blockers used to treat exudative ARMD?
1) bevacizumab (Avastin) - funded
2) ranibizumab (Lucentis) - restricted funding
3) aflibercept (Eylea) - better binding - not funded
Tx with anti VEGF usually starts with what regime? What else is also sometimes used in conjunction with anti-VEGFs?
monthly injections for 3 months then monitor for stability.
Intra-vitreal steroids
What conclusions came about from the AREDS studies?
- zinc and antioxidants modestly effective in slowing progression of some AMD
- adding lutein + zeaxanthin, DHA + EPA or both did not further reduce risk of progression
What sort of nutritional advice could you give to Px to reduce risk of ARMD?
- increase intake antioxidants - colored veges, omega 3 (fish), vitamin supplements
What other advice could you tell patients to reduce risk of ARMD (4)
- avoid smoking
- improve lifestyle
- home amsler grid
- UV eye protection
Compare and contrast type 1 and 2 diabetes
Type 1 - rapid onset in youth - dependent on insulin - 10% of diabetes Type 2 - progressive - variable dependence on insulin - can be treated with diet, exercise, weight control, oral agents and insulin - 90% diabetes
Factors that determine presence of DR
- duration of disease
- level of blood glucose (HbA1c)
- poor metabolic control
- HT
- pregnancy
- nephropathy
- elevated blood lipids
- smoking
HbA1c levels have been classified as a percentage and categorise people as not diabetic or at risk. What are the values?
Not diabetic <6%
At risk 6-7%
Diabetes can cause what changes to the cornea? (4)
- epithelial changes
- reduced sensation and tear production
- possibly thicken stroma
- early aging signs at endothelium
Diabetes can cause what changes to iris and ciliary body? (3)
- vacuoles of pigment epithelium
- pinhole trans-illumination defects
- rubeosis irides
Diabetes can cause what changes to lens? (4)
- snowflake cataract
- increased risk of age-related cataracts
- varying of refractive power
- more post op complications after cataract surgery
Diabetes can cause what changes to the vitreous? (2)
- haemorrhage
- possibly early PVD
Diabetes can also cause diplopia, ptosis and anisocoria through complications of which cranial nerves?
III
IV
VI
Non-proliferative signs of DR are related to loss of which type of cells?
pericytes
Signs of NPDR (8)
- microaneurysms
- macular oedema
- dot, blot, flame haemorrhages
- hard exudates
- intraretinal oedema
- CW spots
- IRMAs
- venous beading
PDR is associated with retinal _____ causing the formation of ________ and involves ______ growth factors
hypoxia
new vessels
vascular endothelial
Signs of PDR (4)
- NV
- fibrous tissue
- pre-retinal or vitreous haemorrhages
- tractional RD
Clinically significant macular oedema (CSMO) is defined as oedema within how many DD?
1/3
Macular oedema is defined as within?
2DD of centre of macula
Assessment of macular oedema requires _______ ______ and diagnosis requires _____
stereoscopic examination
OCT
CSMO is treated with? (2)
Anti-VEGFs
laser
What sort of examination is required for every diabetic Px?
DFE
What two tests are needed for detecting DR?
FA
OCT
Grade R0 (No DR) - clinical signs and outcome?
No abnormalities
For type 1 - re-screen at 2 years, adjusting for clinical modifiers
For type 2 - re-screen at 2-3 years, adjusting for clinical modifiers
Grade R1 (Minimal) - clinical signs and outcome?
<5 microaneurysms or dot haemorrhages
Re-screen at 2 years depending on clinical modifiers
Grade R2 (mild) - clinical signs and outcome?
> 4 microaneurysms or dot haemorrhages
Exudates >2DD from fovea
Some blot and larger haemorrhages acceptable
If more than 20 microaneurysms or haemorrhages per photographic field, upgrade to R3
Outcome - Re-screen after 12 months
Grade R3 (moderate) - clinical signs and outcome?
Any features of mild
Blot or larger haemorrhages
Up to one quadrant of venous beading
Outcome - re-screen 6 months
Grade R4 (severe) - clinical signs and outcome?
One or more of:
- definite IRMA
- two quadrants or more of venous beading
- four quadrants of blot or larger haemorrhages
Outcome - review by ophthal within 6 weeks
Grade R5 (proliferative) - clinical signs and outcome?
One or more of:
- NV
- sub-hyaloid or vitreous haemorrhage
- traction RD or retinal gliosis
Outcome - urgent referral to ophthal
Adequate quality of photos for grading require a minimum field size of? When is it required to take a superior and inferior image also?
two 45 degree fields
type 1 diabetes or R3 and higher
Taking a quality diabetic photo should produce an overlap of at least how many degrees horizontally and vertically?
75 horizontally
45 vertically
Which form of treatment for DR reduces risk of VA loss and is more effective if undertaken before high risk features are present?
photocoagulation
Symptoms of vitreous inflammation (4)
- Floaters
- Ache ?
- Decreased VA (depending on maculopathy)
- Red eye (depending on location)
Signs of vitreous inflammation (7)
- vitritis
- vitreous opacities
- PVD
- retinitis/scarring
- CMO
- cataract
- RD
What in particular causes vitreous inflammation?
intermediate and posterior uveitis
Which vitreous opacity are calcium soaps suspended in the vitreous that do not usually affect vision, usually do not move and is associated with diabetes and vascular disease?
asteroid hyalosis
Which vitreous opacity is any part of the hyaloid system that can remain and can cause floaters. They are also known as Mittendorf’s dot and Bergmeister’s papilla
hyaloid remnants
Which vitreous opacity often results from NV or retinal tears?
intra-vitreal haemorrhage
Which vitreous opacity can result from: trauma intraocular surgery intraocular inflammation RD
pigment particles
Which vitreous opacity are cholesterol crystals which:
- tend to form and settle in liquefied vitreous
- can be stirred up with movement
- tend to occur following vitreal inflammation and haemorrhage
synchysis scintillans
Persistent hyperplastic primary vitreous is what?
failure of regression of embryonic hyaloid vascular system
PHPV is usually unilateral/bilateral, common/rare, causes __________ and often associated with what (4) conditions?
unilateral
rare
leukocoria
microphthalmia, cataract, glaucoma, RD (+ others)
Retinoblastoma originates from where?
any layer of the retina
There are two types of retinoblastomas which are?
endophytic - grows inwards towards vitreous
exophytic - grows outwards into subretinal space –> RD + haem
Retinoblastomas can cause? (4)
- leukocoria
- strabismus
- intra-ocular inflammation
- increased IOP
What symptoms are common during PVD?
flashes and floaters
PVD can cause what other three things
RD
retinal haemorrhage
macular traction syndrome (and possible macula hole)
Lattice degeneration represents areas of (1) and (2) which run circumferentially between what two structures (3/4)?
1) retinal thinning
2) capillary drop-out
3) ora serrata
4) equator
Snail track degeneration is likely a variant of what other condition?
lattice degeneration
Which two conditions can contain atrophic holes and which is less likely to cause RD?
lattice degeneration and snail track degeneration
snail track less likely to cause RD
What peripheral retinal condition is thought to be congenital (may be degenerative) is usually seen in the inferio/temporal quadrant is associated with areas of retinal thinning with loss of RPE with Bruch’s membrane intact and is of NO CONSEQUENCE
Pavingstone degeneration
Which peripheral retinal condition is very common, tends to increase with age and is characterised by cysts in the NFL or OPL and can be a precursor to what condition?
cystoid degeneration
retinoschesis
Which peripheral retinal condition can be mistaken for a RD, is usually bilateral, is flat, sharply demarcated and considered to be due to abnormal vitreo-retinal traction or a prominent vireous base (of no consequence)
white without pressure
RPE degeneration and disorganisation of pigment granules in the perpheral retina is characteristic of which condition? This condition can also have what characteristic which makes it look similar to RP?
1) reticular (pigmentary) degeneration
(a condition of no consequence)
2) can have bone spickle apperanace
What is retinoschesis (incl what layer is involved)
Splitting of neuro-retina (outer plexiform layer)