Fluorescein angiography involves injecting fluorescein dye intravenously and photographing its progression through the retinal vasculature using a fundus camera. It is used to diagnose and monitor various retinal conditions. The angiogram has early, mid, and late phases where different vascular structures are visualized as the dye circulates. Abnormal findings include hypofluorescence from blockages or poor perfusion and hyperfluorescence from leakage, staining, or transmission defects. Indocyanine green angiography uses a different dye that is visible in the infrared spectrum, allowing visualization of the choroidal circulation. It provided a more precise localization of a leak in one case, guiding a focal treatment that improved vision compared to the planned treatment based

2. Fluorescein angiography
Refer to photographing fluorescein dye in the retinal
vasculature following I.V injection of fluorescein
solution

3. Fundus Camera

4. Indications
Diabetic retinopathy
Age related macular degeneration
Central Branch retinal vein occlusion
Central serous chorioretinopathy
Central Branch retinal artery occlusion
Clinical researches

6. 10 seconds following injection.
The major choroidal vessels are impermeable to fluorescein, but the
choriocapillaris leaks fluorescein dye freely into the extravascular space.
Early Phase:
1. Choroidal flush.

7. 12 seconds
A delay  circulatory problems
2. Arterial phase.

8. Complete filling of the retinal capillary bed follows the arterial phase and
the retinal veins begin to fill
3. Arteriovenous phase.

9. 30 seconds after injection.
The perifoveal capillary network is best visualized
4. Venous phase.

10. recirculation phase
2 to 4 minutes
The veins and arteries remain roughly equal in brightness.
Mid Phase

11. gradual elimination of dye
7 to 15 minutes
Late staining of the optic disc is a normal finding.
late hyperfluorescence  Abnormality
Late Phase

13. Abnormal angiographic
findings
Hypofluorescence
Filling defect
Blocking defect
Hyperfluorescence
Autofluorescence
Psuedofluorescence
Transmission or "window” defect
Leakage
Pooling
Staining

14. Hypofluorescence
Hypofluorescence is the reduction or absence of
normal fluorescence.
Hypofluorescence is caused by either blockage of
the normal fluorescence pattern or abnormalities in
choroidal or retinal vascular perfusion.

15. Blocking
caused by blood or deposition of
abnormal materials such as lipid
exudate, lipofuscin, xanthophyll
pigment or melanin pigment.
preretinal hemorrhage from
proliferative DIABETIC retinopathy
retinal and choroidal vasculature
subretinal blood from exudative
age-related macular degeneration
 only the choroidal circulation

16. Filling defect
(Hypoperfusion)
Retinal: retinal arterial and
venous occlusions and
ischemic disease
Choroidal: ophthalmic
artery occlusion, giant cell
arteritis, and hypertensive
choroidopathy.

17. Hyperfluorescence
Hyperfluorescence is an increase in fluorescence
resulting from the increased transmission of normal
fluorescence or an abnormal presence of fluorescein
at a given time in the angiogram.

18. Autofluorescence
occur naturally in certain
pathologic conditions
such as optic nerve drusen
and astrocytic hamartomas.

19. Transmission defect
Depending on the density
of retinal pigmentation
background fluorescence
from the choroid can be
visible as
hyperfluorescence
damage of the retinal
pigment epithelium

20. Leakage defect
(extravasation)
disruption of the retinal
vascular endothelial cell tight
junctions or the breakdown of
the tight junctions between
retinal pigment epithelial cells
proliferative diabetic
retinopathy, optic disc or
retinal neovascularization

21. Staining
fluorescein dye into certain
tissues.
Drusen and chorioretinal
scars
Normal staining can occur
in the optic nerve and
sclera as a result of normal
choroidal leakage

22. Pooling
accumulation of dye within
a distinct anatomic space.
serous detachments of the
sensory retina or the retinal
pigment epithelium
Central serous
chorioretinopathy

23. Indocyanine Green
Angiography
ICG is used to acquire an angiogram of the choroid.
ICG angiography uses Indocyanine Green dye, which
fluoresces in the infra-red (non-visible) light.
The infra-red wavelenths have the ability to penetrate the
retinal layers making the circulation in deeper layers
visible when photographed with an infra-red sensitive
camera.

24. Case Example
In the case of a patient with 20/100 vision, the
fluorescein angiogram demonstrated leakage of
fluorescein dye over a large area near the fovea.
Traditional treatment would dictate that the entire
area of leakage be treated with laser surgery.
The treatment of this lesion would cause an instant
decline in vision to 20/400.

25. Cont.
The ICG angiography, performed on the same day,
reveals a pinpoint leak not visible with fluorescein
angiography.
Focal treatment based on the ICG angiogram
caused an increase in vision from 20/100 to 20/80

26. Late Phase FA Late Phase ICG

28. Refrences
OPHTHALMIC PHOTOGRAPHERS’ SOCIETY
Ophthalmology and Visual Sciences, UNIVERSITY
IOWA CARVER COLLEGE OF MEDICINE
Diagnostic Procedures in OPHTHALMOLOGY by HV
Nema & Nitin Nema