AMD Flashcards
RF for AMD
AGE! Female HTN, hyperchol, CVD, FHx Smoking Hyperopia Light iris color White
What are 2 major susceptibility genes for AMD
CFH (1q31) - codes for complement factor H ARMS2 (10q26) - gene product poorly understood
Where are basal laminar and basal linear deposits?
Basal laminar - between the plasma membrane and the basement membrane of the RPE
Basal linear - within the inner collagenous zone of Bruch membrane (memo basal linear is in Bruchs)
What are the size categories for drusen?
What is a drusenoid PED?
Small (< 67 um)
Intermediate (63-124 um)
large (>125 um) – 125 um width of blood vessel
drusenoid PED: confluent large drusen that coalesce into a PED (>350 um)
AREDS study: Risk of progression to stage 4 AMD in patients with stage 2 and stage 3? what is defined by stage 2/3?
Over a 5 year period risk of progression to stage 4
Stage 2: many small drusen or few intermediate drusen. 1.3%
Stage 3: many intermediate drusen or even a single large druse (stage 3). 18%
4 types of drusen
how do soft and hard drusen show up on FA?
Findings on OCT?
hard: discrete and well demarcated. well-defined focal areas of lipidization or hyalinization of the RPE-bruch membrane complex.
- Typically window defect on FA
- OCT: sub RPE elevations or small RPE detachments with no IRF and SRF
soft: amorphous and poorly demarcated. diffuse thickening of hte inner aspects of the bruch membrane (basal linear deposits) - more likely to progress to atrophy or CNV than an eye with only hard drusen.
- Typically slowly and homogenously stain late because of pooling of FA in the sub-PED compartment.
- OCT: sub RPE elevations or small RPE detachments with no IRF and SRF
Reticular pseudodrusen: seen on FAF, smaller then soft drusen, superior macular region, associated with progressive atrophy, GA, CNV.
- OCT - above the RPE
Drusen in pts < 50: familial or early-onste drusen. Include: large colloid drusen, malattia leventinese, and cuticular drusen.
What are the patterns of abnormalities of the RPE in AMD
- Focal hyperpigmentation. Typically blockage on FA and hyperreflective outer retinal foci on SD-OCT.
- nongeographic atrophy. atrophy that does not cover a contiguous area and may appear as mottling or depigmentation
- geographic atrophy: area of absent RPE is contiguous. Choroidal vessels more visible, outer retina thin, choriocapillaris attenuated. Window defects on FA, OCT loss of RPE and inner segments ellipsoid and photoreceptor layer. Dense hypoautoF on FAF. Often fovea involvement LATE in disease process.
Ddx for nonneovascular AMD
CSC
Pattern dystrophy
adult-onset vitelliform maculopathy
drug toxicity (ie plaquenil)
AREDS 2 results at 5 and 10 years. Definition of intermediate and advanced AMD?
Intermediate or advanced AMD
-
At 5 years
- 25% risk reduction for progression
- 19% risk reduction in rates of moderate vision loss
- At 10 years
- 44% of placebo vs 34% of supplement eyes had advanced AMD (27% RR)
Definition of intermediate and advanced:
- Intermediate (stage 3): at least 1 large druse, 10 or more intermediate drusen or nonsubfoveal GA
- Advanced (stage 4): nAMD, GA in only one eye
What is are the 4-points on the 4-point grading scale developed by AREDS for classifying the severity of AMD?
- presence of 1 or more large (>125-µm diameter) drusen (1 point)
- presence of any pigment abnormalities (1 point)
- for patients with no large drusen, presence of bilateral intermediate (63–124 µm) drusen (1 point)
- presence of neovascular AMD (2 points)
What are the AREDS2 vitamins with doses?
Vitamin C 500 mg
Vitamin E 400 IU
Lutein 10 mg
Zeaxanthin 2 mg
Zinc 80 mg
(VVLZZ)
Findings in AREDS2 study?
Lutein and zeaxanthin similar effect to beta carotene
LCPUFA not helpful
Lung cancer in pts who previously smoked taking beta carotene
conclusion: replace beta carotene with lutein and zeaxanthin and NOT add LCPUFAs
Clinical signs of CNV in AMD?
SRF
IRF
exudate and/or blood
pigment ring or gray-green membrane
irregular elecation of the RPE or a PED
RPE tear
sea fan pattern of subretinal vessels
intraretinal blood and CME may indicate type 3 NV (from the deep capillary plexus of the retinal circulation)
what are the 3 types of CNV in nAMD?
type 1: sub-RPE
- vascularized serous or fibrovascular PED
type 2: sub-retinal
- lacy or gray-green lesion
type 3
- new vessels sprouting from the deep capillary plexus (RAP retinal angiomatous proliferation)
- –> if these lesions progress they lead to a hypertrophic, fibrotic, disciform scar*
Polypoidal choroidal vasculopathy
variant of type 1
serosanguineous RPE detachments
network of polyps (string of pearls)
typically hypertensive middle aged women (initially found in asian or african american ancestry)
often peripapillary and multifocal
OCT and ICG useful for identifying the lesions
