7 - Age Macular Degeneration Flashcards
What are the two genes explaining AMD?
Tyr402His(5 fold) and Ala69Ser(7 fold) Note: Both are complement of the H gene
What is the risk of a Smoker getting AMD?
Twice Note: Reduces chorodial blood flow, decreases pigment in RPE, depresses antioxidants levels and imune system activation
What is the biggest factor for AMD?
Age Note: Risk increases with advancing age Race: Caucasian is another demographic Gender: Female
What is the hallmark for Dry AMD?
Drusen RPE Hyperpigmentation RPE atrophy
What are the hallmark findings for WET AMD?
Choroidal NV Subretinal/SUB RPE fluid or blood
What is the most common type of AMD?
Dry AMD Note: Non exudative, Atrophic, non bleeding and is about 85 to 90% of cases
Which layer of the retina will have lipid deposits?
Bruch’s membrane
What vasculature is effected in AMD?
Choriocapillaris
What are the balance molecules for Bruch’s membrane?
Collagen (Type 1 Increase with aging and Type 4 decrease as one ages) Laminin (Decrease as aging occurs) Fibronectin (Decrease as aging occurs) GAG’s (Increase with aging) Matrix Metalloproteinases
What is a distinction of the Pathophysiology of DRY AMD?
Photoreceptor function is decreased Note: Usually due to OXIDATIVE STRESS (RPE) and INFLAMMATION (Choriocapillaris)
Oxidative stress produces what type of product which impacts the RPE?
Free radicals
Injury of endothelial cells of the choriocapillaris and RPE results from inflammation. What is happening?
Activation of complement cycle which results in the formation of the Membrane Attack Complex (MAC) –> Lyses pathogens
What is damaged first in the inflammation?
Choriocapillaris
What specific protein is damaged in the RPE?
Matric metalloproteins (MMP’s) Note: Products are backed up in the basal lamina of the RPE and Bruch’s membrane and get stuck on the RPE
What are the two types of Drusen deposits?
- Basal Laminar deposits (Lipid and Collagen) 2. Basal Linear deposits (phosopholipid vesicles and granules)
What is the size criteria for Drusen?
small (usually
What is the boundary criteria for Drusen?
- hard (discrete and well demarcated) 2. soft (amorphous and poorly demarcated) 3.confluent (contiguous boundaries between drusen)
What are the two main materials Drusen is made of?
Lipid and Hyalin Material
What is the predisposing formation from hydrophillic drusen?
Chorodial Neovascularization will occur
NV occurs during WET AMD and what product does the new vessels contain to create a membrane (network)?
Fibroblasts
What is the most common VGF?
Vascular Endothelial Growth Factor
True or False. Pt will not exhibit vision loss?
True
What are the two types of CNV?
- Classic - Uniform lesion with typical IVFA pattern 2. Occult - Irregular lesion with typical IVFA
What is a Disciform scar?
Fibrous tissue proliferation (Hemorrhage or Hyperplasia of the RPE)
What is the classification of AMD Criteria?
Since IVFA use to the be Gold standard, what mechanism or machine which deminished the usage of IVFA?
OCT
What is the benefit of using ICG FA?
Finding Occult CNVM
What type of defect will you notice on the OCT if there is an RPE Atrophy?
Window Defect
True or False. With RPE Atrophy, the image of the Dry AMD can be seen upto the choroid?
True.
An OCT image shows complete irregularity in the the macula area. What is usually directly correlated to Wet AMD and this irregularity?
CNVM
True or False. Hard exudates will stain later in stage compared to soft exudates?
False. Hard will immediatly Fluoresce and Soft will copulate over time. Leakage will occur in soft exudates
What is the follow up protocol for Dry AMD?
- 6-12 months, Depends on appearance
- Early hard drusen only-about 12 months
- Some soft drusen-about 9 months
- Extensive soft drusen-about 6 months
- Geographic atrophy-6-12 months
What is the protocol for follow up of a WET AMD?
- Confirm fundoscopic findings with ancillary tests
- Any new area of CNVM, bleeding, fluid, etc MUST be referred to OMD for treatment
–Treatment of Wet AMD is outside of scope of OD in all 50 states
- OMD will proceed with treatment
- OMD will follow-up every 1-3 months until CNVM inactive
What is follow up protocol for Disciform Scar?
- If scarring extensive, new treatment won’t be very effective
- Monitor based on risk of more visual impairment
- Usually every 12 months
- If extensive scarring, extensive VI
What is the most common testing conducted on AMD pts?
Amsler Grid
What is the benefit of PHP; in regards to photoreceptors?
Sensitivity to photoreceptors
What is the treatment of Dry and Wet AMD?
•Dry
–Oral vitamins
–Experimental treatments
•Wet
–Oral vitamins
–Intravitreal injections
–(laser, PDT)
What was the most effective measure for individuals with Int. AMD or Advanced AMD in 1 eye?
High levels of antioxidants and zinc
Formula: AREDS 1 Formula
- 500 milligrams of vitamin C
- 400 international units of vitamin E
- 15 milligrams of beta-carotene (concern in smokers developing lung cancer)
- 80 milligrams of zinc as zinc oxide
- 2 milligrams of copper as cupric oxide
–Prevent copper deficiency, which may be associated with high levels of zinc
•OK to take multivitamin in addition
What is the formula in AREDS 2?
- 500 milligrams of vitamin C
- 400 international units of vitamin E
- 80 milligrams of zinc as zinc oxide
- 2 milligrams of copper as cupric oxide
–Prevent copper deficiency, which may be associated with high levels of zinc
- 10 milligrams lutein
- 2 miligrams zeaxanthin
What is the protocol of IV injections in AMD pts?
- Upon sign of CNVM, injection monthly for 3-6 months, then as needed after
- “Treat and extend”-after initial treatment and stabilization, intervals are adjusted based on clinical signs: extended 2 weeks if no bleeding, shortened by 2 weeks if bleeding
What is Purtscher retinopathy?
Loss of vision after acute compression injuries to the thorax or head
Presentation: CWS, Heme and retinal edema
FA: Arteriolar obstruction and leakage
May occur: APD and disc edema
What is Valsalva or Venous retinopathy?
IO Venous pressure increases. Around macula, you will see a hemes. Located on the NFL,
Ex: Large amount of blood right infront of the macula (fundus photo).
What is hyperviscosity syndrome?
Vascular occlusion, therefore a flow decrease damage vessels with leakage and ischemia; usually due to high protein (hyperglobulinemia)
What is HIV retinopathy?
Many hemes; CWS; decreased VA and advanced pts will have it. This will tell you that you will have an asymptomatic issues.
What is the presentation of interferon retinopathy?
CWS, hemes, block FA but after discontinuation will stop all the symptoms.
Note: Monitor monthly if there is retinopathy and if not 3 months RTC
What is Talc Retinopathy?
Talc is inert filler in methylphenidate hydrochloride tablets: crushed for IV drug use
IV to lungs: Infarcts to right to left and CRVO will occur
What is Terson syndrome?
Vitresous and sub-ILM or subhyaloid hemorrhage (sub ILM)
Usually occurs due to trauma
1/3 subarachnoid or subdural heme
What is child abuse syndrome?
Due to trauma; you will see blood in the back of eye and this is the only sign that you could find.
Heme’s and 80% of shaken baby syndrome you will see this.
