AMD Flashcards
what is the size of half a central retinal vein width (as it emerges from the disc)
63 micrometers
risk factors for AMD (NICE guidelines)
- Diet low in omega 3 and 6 and cartenoids and minerals is a risk of AMD
- Lack of exercise
- Smoking – biggest
- Older age
- Hypertension
- Family history of AMD
- BMI of 30 kg/m2 or higher
- Presence of AMD in the other eye
- High fat diet
AMD dry tx
- No treatment available
- Advise on lifestyle modifications eg smoker
- Advise patients on nutritional supplements
- Educate about symptoms of progression and self-monitoring eg with amsler
- Aim: to slow down the progression
- NICE doesn’t say much about supplements, since mixed and depends on the px
when is it classified as normal when there is drusen present (i.e no AMD)
no sign of AMD
small hard drusen (<63 micrometers only)
these patients do not have AMD
classification of low risk of progression early AMD
- Medium drusen (≥63 but <125 micrometres), OR
- Pigmentary abnormalities.
(not both together)
classification of medium risk of progression early AMD
- Large drusen (≥125 micrometres), OR
- Reticular drusen, OR
- Medium drusen with pigmentary abnormalities.
classification of high risk of progression early AMD
- Large drusen (≥125 micrometres, bigger than vein width) with pigmentary abnormalities, or
- Reticular drusen with pigmentary abnormalities, or
- Vitelliform lesion without significant visual loss (best-corrected acuity better than 6/18), or
- Atrophy <175 micrometres and not involving the fovea
classification of late dry AMD
- Geographic atrophy (in the absence of neovascular AMD).
- Significant visual loss (6/18 or worse) associated with:
- Dense or confluent drusen (drusen joining together), or
- Advanced pigmentary changes and/or atrophy, or
- Vitelliform lesion.
what are drusen
Drusen are sub retinal pigment epithelium deposits of extracellular debris composed of lipids and proteins which sit just below the RPE, or between the RPE and bruchs membrane
what are reticular drusen and what are they also called
Reticular drusen are also known as pseudo-drusen or subretinal drusenoid deposits. Contrary to the drusen which lie below the retinal pigment epithelium (RPE), reticular drusen are located superficial to the RPE, slightly superior to RPE. They are yellowish subretinal lesions arranged in a network and indicate a greater risk of AMD progression.
Retiucular drusen more pale and yellow
what are Vitelliform Lesion, dry AMD
Accumulation of lipofuscin within the subretinal space – causes hyper reflective lesions
dry AMD, atrophy what is it
Geographic atrophy - loss of cells in the fovea - rpe and outer retina (rods and cones are lost). Complete loss or rpe and outer retina if is at least 250 microns wide - can be seen on any OCT- standard research definition
Atrophy – appears as disease progresses in AMD, early stages might be small patches,
RPE absent then choroid is brighter in OCT scan.
dry AMD role of the optometrist
- Make the diagnosis.
- Give relevant advice (including advice on driving and smoking cessation)
- Counselling – diagnosis is often a shock
- Provide Information – needs to be accessible (e.g. large print)
- Monitor – disease progression
- Referral
- Low Vision Services
- For SI or SSI Registration (Ophthalmology)
- To Social Services
management of dry AMD
- No treatment available
- Advise on lifestyle modifications eg smoker
- Advise patients on nutritional supplements
- Educate about symptoms of progression and self-monitoring eg with amsler
- Aim: to slow down the progression
- NICE doesn’t say much about supplements, since mixed and depends on the px
what are the emerging tx in USA
- Complement Factor inhibitors
- FDA approved
- Intravitreal injections
- Monthly or bimonthly
- Utility has been shown in patients with severe dry AMD (Geographic atrophy)
- Likely that geographic atrophy away from the foveal centre will be treated first as this is most beneficial to preserve vision by slowing rate of growth of geographic atrophy
Nutritional supplements AREDS (age related eye disease study) what is it
Large scale, randomized, double-masked, placebo- controlled clinical trial (RCT)
Looked at effectivity of supplements in delaying preventing onset progression of AMD
AREDS and AREDS 2 – Outcomes
antioxidant supplements reduced the risk of AMD progression in those with moderate/ high risk of progression formulation from AREDS 2 study,
- since ARED1 study contained Beta-carotene which is associated with increased risk of lung cancer in smokers so Lutein and Zeaxanthin instead (all new supplements do not ahve beta carotene anymore)
But, a systematic review showed that supplements had no effect in the prevention of AMD
Omega-3 fatty acids may help prevent AMD
Vitamin E and Betacartoene are associated with increased mortality
what was administered in AREDs 2 study
AREDS 2 - Multicenter, randomized, double-masked, placebo-controlled clinical trial to evaluate
* Placebo,
* Lutein (10 mg)/zeaxanthin (2 mg),
* Omega 3 fatty acids (DHA 350 mg and EPA 650 mg), and
* Lutein/ Zeaxanthin and Omega-3 fatty acids combination
In addition, participants were administered either
* the original AREDS formulation (vitamins C, E, and beta-carotene, and zinc with copper) or
* some modification of the AREDS formulation (either elimination of beta-carotene, lowering of the zinc, or the combination of the two)
smoking cessation in AMD
Smoking increases oxidative stress
Second most important risk factor (after age)
Most important modifiable risk factor
Smoking
Slows down choroidal blood flow
Promotes ischemia
Reduces macular pigment
other lifestyle modifications in AMD
Increased physical activity > No direct evidence
Reduced alcohol consumption > Unclear whether moderate consumption is a risk
Reduction of waist-hip ratio > Especially in obese – unclear?
Diet rich in omega-3 polyunsaturated fatty acids > Evidence for decreased risk
when do we refer px’s with dry amd to hes
for certification of sight impairment or low vision services
new symptoms that may suggest late AMD (wet active)
to participate in research for new tx options
benefits of registration for sight impairment
- National Entitlement Card (NEC)
- Scottish National Blind Persons Scheme
- Disabled Persons Railcard
- TV Licence discount
- Blue Badge
what do rehabilition clinics do
- Rehabilitation based on adaptation to vision loss
- Advise on low vision services
- Support patients in dealing with visual impairment
- Direct to suitable information, e.g. Macular Society
reasons for referral to social services
- RNIB
- Eye Care Liaison Officer
- Virtual or in person
- Discuss diagnosis and assess needs
- Macular Society
- Sight loss and depression are linked
- The prevalence rates of depression in elderly populations with sight loss are between 25 per cent and 45 per cent.
- The relative risk of depression is estimated to be around 3.5 times higher for those with sight loss compared to those fully sighted.
- It is estimated that up to 30 per cent of those living with age related macular degeneration experience moderate to severe depressive symptoms due to vision loss.
- Falls are a major cause of disability
- 1.7x higher in people with sight loss
- 47% of falls in low vision patients are due to their sight loss
- The cost to NHS of falls associated with sight loss in Scotland is at least £1million per annum.
what could late AMD (wet active) be (classfication)
classic chorodial neovascularisation
occult (fibrovascular PED- pigment epithelium detachment and, serous PED with neovascularisation).
- Mixed (predominantly or minimally classic CNV with occult CNV).
- Retinal angiomatous proliferation (RAP).
- Polypoidal choroidal vasculopathy (PCV).
- Classic choroidal neovascularisation (CNV)
a neovascular lesion is identified that extends from the choroidal vessels through the Bruch’s membrane and RPE and grows into the subretinal space.
- Occult (fibrovascular PED- pigment epithelium detachment and, serous PED with neovascularisation).
neovascular lesion is located below the RPE.
features of Late AMD (wet inactive) – no new leakage from vessels and no new rapid damage
fibrous scar
* Sub-foveal atrophy or fibrosis secondary to an RPE tear.
* Atrophy (absence or thinning of RPE and/or retina).
* Cystic degeneration (persistent intraretinal fluid or tubulations unresponsive to treatment).
wet AMD management
- Urgent referral – new presentation
- NICE guidance:
Make an urgent referral for people with suspected late AMD (wet active) to a macula service, whether or not they report any visual impairment. The referral should normally be made within 1 working day but does not need emergency referral. - Electronic (via SCI Gateway) Via Macular Pathway
- Not usually ‘letter in hand’ same day referral – since tx today or in few days doesn’t make difference but months do make a difference
- Patient needs to be seen at Macular Clinic (where OCT and Fluorescein Angiography are available)
what is the tx like with antiVEGF for wet AMD
- Course of 3 injections
- Review/ monitoring period
- May require further courses of injections
- Royal college recommend a loading dose for 3 monthly injections to start. Treat and extend regimen is recommended after that dependent on OCT and acuity results
AMD patients discharged back to community - role of optom
- Optometrist to monitor for progression/ new fluid
- OCT is required
- Re-referral to HES
- Involvement in anti-VEGF treatments
discharge of AMD patients from HES based on
- how stable the condition is and
- if treatment will bring any further benefits to the patient
- Discharged patients should see an optometrist or GP urgently if any new symptoms develop
- In particular patients who have been treated for wet AMD in one eye and develop problems in the contralateral eye – at higher risk
aim of management for AMD (Wet)
- Prevent (further) vision loss
- Halt progression of new vessels
Types of anti VEGF drugs
- ranibizumab (Lucentis®) Novartis AG
- bevacizumab (Avastin®) Roche Holding AG
- aflibercept (Eylea®) Beyer AG
- Scottish Medicines Consortium has approved ranibizumab and aflibercept for use in NHS Scotland
- NICE has approved ranibizumab for treating wet AMD
- Bevacizumab is not used on the NHS, mainly for political and legal reasons
tx options for serous pigment epithelial detachement (PED) without neovascularisation
- Treatment options are different for serous PED - half dose photodynamic therapy may be preferred If no evidence of neovascularisation
- For non-neovascular AMD with fluid, again anti vegf is ineffective and monitoring is all that can be done
which supplements would you give a smoker AMD dry
- Needs to be lutein since smoker – do not give smoker caratonoids as it can increase risk of lung cancer in smokers
AMD OCT - what does (whiter) patches in the choroid mean
atrophy in RPE (above the atrophy is the photorecptors so VA affected, central drusen and foveal involvement
what does it mean when there is a fibrosis scar
no tx (antiVEGF) will work to make it better, only can monitor and counsel
supplements for the other eye
Wet ARMD Referral Guidelines
NICE
* The best-corrected VA is between 6/12-6/96
* There is no permanent structural damage to the central fovea
* The lesion size is less than or equal to 12 disc areas in greatest linear
dimension
* There is evidence of recent presumed disease progression
AMD HM VA management
cannot do anti VEGF, no tx avaliable for this px
which cases for wet AMD require immediate action
- Intra-retinal or sub-retinal fluid
- With or without Choroidal Neovascular membrane
- With or without haemorrhage
- All require immediate action
- Usually include suddenly reduced VA (but not always)
- Usually have associated visual distortion
what is the tx with intravitreal injections
1 injection/ month for 3 months, then review. (baseline tx plan for any new AMD).
in who do we see CSR central serous retinopathy
- Younger patients
- Stress
- Type A personality
- Recurrent
- No referral – usually self-resolving
- Counselling important
- CSR uncommon in older patients
management for CSR
- Management no referral and monitor, self resolves.
- No management in HES unless longstanding
- Recall 8-12/52
- CSR is unilateral is almost all cases.
- Elevation then hyperopic prescription – depth perception would not be as good as well, wouldn’t give rx since vision will get back to normal and the patient would be over plussed.
- If it gets worse and not resolving come back to see me
- Wouldn’t give amsler chart for CSR
