Maculopathy & AMD Flashcards
Age-related maculopathy (ARM)
- Definition?
- Characteristics? RPE changes?
- Exaggeration of the ‘normal’ ageing process
-
Characterised by
Drusen
Hyperpigmentation
or depigmentationof the RPE associated with drusen
Age-related macular degeneration (AMD)
- Definition? In relation to ARM?
- Characterised by? (4)
G
P
S
S
- Advanced, sight-threatening stage of ARM
- Characterised by
- Geographic atrophy of the RPE with visible underlying choroidal vessels
- Pigment epithelial detachment (PED)
- Subretinalor sub-RPE choroidal neovascularization (CNV)
- Scar tissue, haemorrhage and exudates
AMD risk factors?
- Age
- ARM
- Race
- Positive family history
- Cataract
- Biomarkers for cardiovascular disease
- Smoking
- Obesity
- Hypertension
Drusen
- What cause it?
- If not cleared, consequence?
- Made up of?
- Effect of Brunch’s membrane?
- Appearance of lesions?
- RPE removes & processes the discs of the outer segments of the photoreceptors
- If not cleared by the RPE, deposits accumulate in Bruch’s membrane
- Made up of lipids
- Bruch’s membrane thickens as a result of the deposits
- Discrete, sub-retinal yellow lesions
Drusen
- Symmetrical?
- Number, size, shape?
- Relationship to age?
- Usually symmetrical in both eyes
- Can vary in number, size, shape etc
- Rarely seen before age 45 years
Increase in size & number with advancing age
Drusen types?
Drusen and AMD
Atrophic AMD
- Other name? Aka?
- Why atrophic?
- Affect what structures?
- Patient present with?
- Affect one or both eye? Symmetrical or not?
- “dry” AMD
- Atrophy which progresses slowly
-
Affects:
Photoreceptors
RPE
Choriocapillaris - Gradual vision impairment. Over months or years
- Affects both eyes (often asymmetrically)
Sign?
Atropic AMD
Greyish
Can’t really see where macula is
Sign?
Atropic AMD
Can see edges of atrophy
If look clearly, can see blood vessels of choroid
Sign?
Atrophic AMD
Big scar over macula
Majority of rods and cones ( haemorrhage)
Progress slowly over time.
Jean below
yellowish, atrophic , drusen not obvious, vision affected severely
Sign?
Atrophic AMD
Window defect
Brightness of choroidal vessels
Ischaemic area - More profound appearance
Artifarct
RPE detachment
What structure involve? What cause changes?
Pt complant of?
Vision affected?
- Bruch’s membrane thickens up & impedes movement of fluid from RPE to choroid
- Patient c/o Metamorphopsia
- Central vision affected
Describe the follow pictures
RPE detachment
Course?
RPE detachment
- Spontaneous resolution
- Geographic atrophy
- Sensory retinal detachment
- RPE tear
1. RPE TEAR
- Where does it occur?
- How does it happen?
RPE tear
- Occurs at the junction of the attached & detached RPE
- Happens if stress causes the tissue to rupture
Can happen spontaneously or following laser Tx1
Instead of everythin pushed upward, there’s a tear. RPE tears and detachment usually seen in wet AMD
Describe image?
RPE TEAR
Detachment= dome ( fluid pushed up)
Tear= flap
Patient c/o vision loss
AMD Review
- Common leading to ?
- Relationship to aging? Uni or bilateral?
- Affect what part vision?
- Classification?
AMD review
- Common cause of VIP and blindness in the western world
- Associated with ageing, usually bilateral
- Affects only central vision
Peripheral vision remains intact - Classification:
- Dry: Slowly-progressing deterioration of vision
- Wet: Neovascularisation & CNVM causes sudden loss of vision
AMD Review
- Principle feature? Location?
- Changes in photoreceptor outer segment?
- If wet, what can grow?
- Drusen between the RPE and Bruch’s membrane
- RPE atrophy & degenerative change in photoreceptor outer segment
- If “wet”, a vascular membrane can grow from the choroid towards the retina
AMD Review
- Difference between vision loss in DRY vs WET AMD ?
- Effect what aspect of vision? (M)
AMD review
-
DRY : Progressive, gradual central vision loss
OR
WET: Sudden, profound vision loss - Affects reading & object recognition
Metamorphopsia
Neovascular “wet” AMD
Cause by? Originate from where?
List 3 growth patterns?
Neovascular “wet” AMD
- C/b CNV originating from the choriocapillaris: grows through defects in Bruch membrane
- 3 growth patterns:
- Sub-RPE: Most common in AMD
-
Sub-retinal: Less common in AMD
Likely in younger patients with myopia or chorioretinitis - Combination of 1 & 2
MECHANISM OF VISION LOSS?
- Principle factor?
- How does it develop? Where?
- Can vision reverse?
- Consequence of persistency?
Mechanism of vision loss
- CNV = Choroidal Neovascularisation
- develops as a result of leakage of blood & serum
Under the retina
Into the retina
Under the RPE - Vision loss from accumulated fluid can be reversed
- If persists =Loss of photoreceptors & RPE
Discformscar forms
Permanent vision loss
IMAGE:
- RPE detach, fluid accumulated & pushed up
- RPE tears both - loss of foveal contour/foveal pit. Macula on either side- as soon as that in gene –> Vision loss
Clinical Presentation of Neovascular AMD?
Vision? Visual field defect? (3)
- Metamorphopsia
- Positive scotoma
- Blurred central vision
Neovascular AMD
Clinical sign?
Sub-retinal: RPE leak out pigment
Neovascular AMD
FFA Investigation
- Role of FFA in FAZ?
- Type of CNV? (3)
- FFA important to detect & precisely locate the CNV in relation to the FAZ
Urgent FFA if patient presents with recent onset of symptoms - Types of CNV
-
1. Classic
Extrafoveal
Juxtafoveal
Subfoveal - 2. Occult
- 3. Fibrovascular PED
Types of CNV -Classic
- Sign on FFA?
Location of CNV in:
Extrafoveal?
Juxrafoveal?
Subfoveal?
- Well-defined membrane which fluoresces brightly on FFA
- Extrafoveal: CNV is > 200μm from centre of FAZ
- Juxtafoveal: CNV closer than 200μm from centre of FAZ
- Subfoveal: Centre of the FAZ is involved
Types of CNV
Occult & Fibrovascular PED ( Pigment Epithelial detachment)
- Characteristics of Occult compared to classic? Sign on fundus?
- Fibrovascular PED?
- Occult: Membrane not well defined (compared with classic) and shows multiple areas of leakage
- Fibrovascular PED: Combination of CNV & PED
Sign?
Pocket of fluid need to be dried up with anti VEGF
Also happen in DR and CRVO
Course of untreated CMV
Haemorrhagic PED
C/b blood vessel rupture within the CNV
VA= HM at best
Course of untreated CMV
Vitreous haemorrhage
Blood breaks through to the vitreous
Rarely occur
Course of untreated CMV
Sub-retinal (disciform) scarring
Occurs after haemorrhage
In-growth of new vessels from the choroid causes a fibrous scar at the fovea
Course of untreated CMV
- What is present? Cause?
- Progression if more severe?
-
Massive exudation develops sometimes if disciformscars are present
C/b chronic leakage from CNV - If severe, sub-retinal fluid spreads beyond macula = peripheral VA ↓
