FAF Flashcards
Lipofusion is a
photoreceptors outer segment phagocytosis byproduct.
lipofusion accumulates in a. RPE b. Photoreceptor c. ganglion cells
a. RPE (and eventually in outer retinal layers) -accumulates naturally with age -too much of this indicates retinal pathology (activity in rpe cell death process) -Too little of this can indicate rpe death
we view lipofuscin via
FAF (It absorbs 500nm-800nm)
what two ways we can accomplish autofluorescing effect? (one we do in lab)
- Extremely bright flash from cannon fundus photography 2.confocal scanning laser ophthalmoscope
The FAF images from cannon are similiar to
similiar to Red-Free and IVFA ….BUT FAF gets you view of lipofusin
Hyper AF=
metabolically sick RPE (too much LF )
Hypo AF= means what about the RPE
RPE DEAD or not present (Lf is gone), signal blockage. cuz LF is supposed to give me fluroscene. light passes through emitting light. but if its not passing there either that RPE is not there or there is a signal blockage somewhere. giving me a dark (HYPO AF)
Guaranteed exam question. How does age affect FAF?
older you get the more metabolic activity you have. =hyperfluorescene
How does a cataract or corneal dx affect FAF? guaranteed exam
darker FAF=hypofluorescene dont get confused with background.
FAF intensity (hypofluroscene or HYPERflourscene) is affected by what type of device used. .
T/F
true , it depends on the modality.
FAF stands for
Fundus AutoFluorescence (FAF)
Ocular fluorophores (retinal fluorophores) are ….. Examples include
Retinal molecules that are exhibit fluorescence emission when excited. -Lipofusion (increases af) -ONH drusen (increases af) retinal molecules that absorb fluorescene -Rhodopsin (decreases AF)
What’s the main difference between Fundus AUTOFluorescence and fluorescein angiography?
FUNDUS AUTOFluorescence is not dependent on circulation like fluorescein angiography
What are the FUNDUS AUTOFluorescence image intensity variables? I.e. what can make the intensity FAF images vary? exam question!
The persons age, Media opacity like a cataract or corneal sizes Pupil size The type of device used - scanning laser phthalmoscope vs fundus camera-based system
What does a healthy FUNDUS AUTOFLUROscene look like?
Insert pic.
What areas are supposed to be dark on FUNDUS AUTOFLUROscene?
Blood vessels because of signal absorption from blood Fovea- because of signal absorption from macular luteal pigment ONH- because of absorption and absence of RPE
What is the gray/grainy appearance on A FUNDUS AUTOFLUORSCENE represent ?
It represents a mild HYPER-FLUORSCENCE (normal levels of lipofuscin in RPE cells )
This pic is an image of a REDUCED or INCREASED AF?
Reduced AF because it has a dark spot representing less signal emission. this is signal absorption .
A reduced AUTOFLUROSCENE represents a A. Hypo AF B. HYPER AF
A. HYPO AF
What can cause a HYPO - FAF? Exam question !!
- Reduced or absent RPE (esp. RPE atrophy {geographic atrophy, central serous chorioretinopathy, hereditary}, RPE tear, reduced visual cycle,) 2. Anterior material blocking RPE (esp- hyperpigmentation {macular pigments, intraretinal &/or sub retinal hemorrhage}, scar tissue, INTRARETINAL AND/OR SUBRETINAL HEMORRHAGE)
*Exam question What can cause an INCREASED AUTOFLUROSCENE? Aka Hyper AF
Drusen Older hemorrhages Excess concentrations of lipofuscin IN RPE (lipofuscinopathies , RPE tear: retracted border) like stargardt dz, pattern dystrophies SUB-retinal autofluorescent material, Window defect (loss of luteal or photo pigment ) Other autofluorescent material
Hypo AF means darker or lighter signal?
darker
HyperAF means darker or lighter signal?
lighter
when you hear signal blockage on FAF, think …
darker. something absorbing Fluorscene making what ever there dark. no fluroscene wavelengths can get through. if no fluorscene, then its hypofluorcene FAF.
FAF predicts pseudodrusen on AMD . t/f
true , its not easily seen with DFE.
FAF is very useful with AMD.
In what 4 ways can we use FAF to help us with patients dx with AMD?
- use it to look for pseudodrusen. (early detection)
- more focal patterns (dark spots) on FAF =increase risk of GEOGRAPHIC ATROPY
- MULTIPLE large areas of increased FAF (soft drusen & hypoplasia) =increase risk of WET AMD
- pt has CNVM but a normal FAF. Means they have a better chance of visual recovery.
all of the following lead to an increase in FAF with dry AMD EXCEPT:
A. soft confluent drusen
b. drusenoid PED (pigment epit detrachment)
c. center of drusen
d. pigment clumping adjacent to drusen
c. center of drusen is hypofluroscent NOT hyperfluros. THE CENTER IS rpe ATROPHY
Reticular pseudo drusen (anterior to RPE) will SHOW HYPOfluro on FAF. t/f
true, its pseudo drusen.
true or false the different hyper AF and hypo AF on FAF show at different times because of the staging of the AMD.
exam question
false. it shows hyper and hypo FAF THROUGHOUT THE WHOLE DISEASE PROCESS. its more so the phsysiological change thats occuring because whats happening .
faf was helpful in determining phenotypes of DRY AMD .
true. but may not be clinical significant.
FAF helps deferentiate between dry amd and non amd dz.
true.
can use OCT and other testing. its dominant familial drusen.
All of the following are associated with WET AMD except:
a. increased AF with RPE tear
b. fluid leading to increased AF
a. its a DECREASE IN AF with borders increase in AF
exam question how do you know its fluid associated with Wet AMD and not just a heme or hard exudate?
i can use FAF. and on the FAF i SHOULD SEE increase in FAF.
if it was a heme or hard exudate, I would first see a absorption and then later an emission due to reorganization.
FAF is NOT a major player in development CNVM (choriodal neovascularization membrane_
ture
type 1 (occult CNVM) is beneath the RPE and will appear HYPO or HYPER AF or both
both
it will be hypo DUE T0 overlying RPE ATROPHY
and hyper AF at borders
type 2 classic CHORORIOD neaovascularization membrane (CNVM) is HYPO , HYPER , BOTH AF.
Whats the main difference between the type 1 and type 2 CNVM
Both Hypo and hyper. Hyper is at the borders
the main difference btwn type 1 and type 2 is HYPO
hypo on type 1 is because of RPE atrophy
hypo on type 2 is because of subretinal fibrovascular net blocking RPE
EXAM question.
FAF is clinically significant for ____. THE SINGLE MOST IMPortant indicator of progression of DRY TO wet amd
geographic atrophy
what does the hyperfluroescene represent on GA?
it can represent actively expanding area if its diffuse hyper beyond geographic atropy = high risk of progression
stargardt disease (macular very dark and black, hyperfluo) early atophy is flecks cam be useful . true or false.
true
best disease….
retinitis pigmentosa ….
new cnvm would show what increased or decreased FAF
increased, the faf depends on the stage of CNVM
longstanding CNVM will show a decrease in CNVM . t/f
decreased, the faf depends on the stage of CNVM .
AF can NOT predict anything with CNVM. it just tells me how long its been there
you note a diffuse pattern on FAF hyperflor .. and inner hypofluo….what do you think it is
geographic atrophy
why would you use FAF on stardgarts disease?
its useful because the flecks and early atrophy wouldnt otherwise be visible.
FAF with stardgats dz correlates with well with vision function
this dz depends on staging too
Previtelliform
No to minimal hyper AF
best disease
•Shed PR debris and lipofuscion accumulate in subretinal space = yolk like lesions
best disease
Psueudohypopyon
Increased AF lower in lesion (gravitational)
Vitelliruptive
Hypo AF with hyper AF border
- 60%: “bulls eye” hyper AF foveal ring which constricts over time with loss of vision ; complete PR loss outside the ring
- 18%: Central foveal hyper autofluorescence – worse visual prognosis
retinitis pigmentosa
THE EXTENT OF Central serous chorioretinopathy (csc) IS BEST SEEN WITH FAF BECAUSE….
- Initially – hypo FAF due to blockage / absorption by subretinal fluid
- As progresses/current activity:
- Fluid present affects RPE function
- Granular hyper FAF
- Longstanding: hypo FAF due to atrophy
plaquinil toxcity
pathy hypo AF due to RPE
exam question
nevus or melanoma
nevus
patchy hyper
