This document provides information about fundus fluorescein angiography (FFA). It begins with basic principles of FFA and the dyes used, including sodium fluorescein and indocyanine green. The purpose, indications, contraindications, technique, phases, and interpretation of FFA are described. Abnormal fluorescence patterns like hyperfluorescence and hypofluorescence are discussed. Recent advances in wide-field imaging and indocyanine green angiography are also summarized.

1. GOOD MORNING!

2. FUNDUS
FLUORESECENCE
ANGIOGRAM
S. B. Dr. Sohan Singh Eye
Hospital

3. contents
1. Basic Principle of FFA
2. Dyes used in FFA
3. Purpose
4. Indications
5. Contraindications
6. Technique
7. Complications
8. Phases
9. Interpretation flow chart
10. Terminologies
11. Abnormal fluorescence
12. Recent Advances in FFA
13. ICGA

4. BASIC PRINCIPLE
– TO UNDERSTAND FLUORESCEIN ANGIOGRAPHY,
KNOWLEDGE OF FLUORESCENCE IS ESSENTIAL.
– TO UNDERSTAND FLUORESCENCE, KNOWLEDGE OF
LUMINESCENCE IS ESSENTIAL.

6. FLUORESCENCE
– FLUORESCENCE is luminescence that is maintained only by
continuous excitation.
– Emission stops when excitation stops.
– Excitation at one wavelength occurs and is emitted
immediately through a longer wavelength.

7. Photographic principle

8. PSEUDOFLUORESCENCE
– Occurs when non-fluorescent light passes through entire
filter system
– It causes non-fluorescent structures to appear fluorescent
– Thus excitation (blue) and barrier (green-yellow) filters
should be matched to avoid overlap of light between them

9. Equipment for Fluorescein
Angiography
– Fundus Camera (20° – 35° – 50°) with Digital Imaging System
- Matched fluorescein filters (Barrier and Exciter)
- 23-G scalp vein needle
- 5ml syringe
- 5ml of 10 % fluorescein solution
- Tourniquet
- Alcohol swab / bandage
- Standard emergency equipment

10. Dyes used in angiography
– Sodium Fluorescein
– Indocyanine Green

11. Sodium fluorescein
 An organic vegetable dye.
Orange – red, crystalline hydrocarbon (C20-H12-O5-Na)
Molecular weight - 376 Dalton
Excited between 465-490 nm & fluoresces at 520-530 nm.
Does not diffuses out through outer and inner blood retinal barrier
It diffuses through choriocapillary and Bruchs membrane
Eliminated by liver and kidneys within 24 hours

12. – Non expensive, non toxic , highly fluorescent that can be
used safely with most people.
– It fluoresces effectively at normal blood ph level(7.37-7.45)
– 80% bound to plasma protein and also with RBC
– High solubility in water.
advantage- can’t pass through tight retinal barriers so
allows study of retinal circulation
disadvantage- can’t study choroidal circulation

13. – Fluorescein Solutions
- 10ml of 5% (500mg)
- 5ml of 10% (500mg)
- 3 ml of 25% (750mg)

14. Indocyanin Green
– Green dye that fluoresces with invisible infrared light.
– It specially useful for studying the deeper choroidal
circulation.
– Safe for general use and less toxic than sodium flourescein.
– Needs special type of fundus camera.

15. Purpose of FFA
– studying the normal physiology of the retinal and choroidal
circulation,as well as disease process affecting the macula.
– Evaluation of the vascular integrity of the retinal and choroidal
vessels
– Check the integrity of the blood ocular barrier.
outer blood retinal barrier breaks in CSR
inner blood retinal barrier breaks in NVD , NVE

16. INDICATIONS
1) Retinal vascular disorders
2) Macular disorders
3) Retinal vascular malformation and tumors
4) Choroidal disease
5) Optic nerve disease

17. CONTRAINDICATIONS
ABSOLUTE
1) known allergy to iodine containing compounds.
2) H/O adverse reaction to FFA in the past.
RELATIVE
1) Asthma
2) Hay fever
3) Renal failure
4) Hepatic failure
5) Pregnancy ( especially 1st
trimester)

18. TECHNIQUE
- Informed consent
- Dilate pupils
- Prepare fluorescein solution, scalp vein cannula & syringe
- Prepare the fundus camera i.e. clean the front lens, focusing
of eyepiece crosshairs
- Position patient for comfort, alignment and focus
- Align and focus camera

19. - Take colour photographs
- Take red-free photographs
- Insert scalp vein cannula
- Inject dye as bolus and start timer
- Shoot exactly at start and exactly at finish of injection
- Again start shooting at 8 sec. in young and 12 sec. in adults
after injection, at interval of 1-2 sec.
- Shoot late pictures at 5 min. and 10 min.

20. Circulation of NAF
Dye injected from peripheral vein
venous circulation
heart
arterial system
INTERNAL CAROTID ARTERY
Ophthalmic artery
Short posterior ciliary artery) Central retinal artery
(choroidal circulation.) ( retinal circulation)
- The choroidal filling is 1 second prior to the retinal filling.

21. INTERPRETATION
– Normal Fluorescein Angiogram
– Consists of the following overlapping phases
- Choroidal phase
- Arterial phase
- Arterial venous (capillary) phase
- Venous phase
– - Early phase
– - Mid phase
– - Late phase
– -Late elimination phase

24. Choroidal Phase
– 10 -12 seconds after dye injected
– Initially patchy filling followed by the diffuse filling as the dye leaks
from the choriocapillaries.
– No dye has reached the retinal arteries.
– Cilioretinal artery if present fills in this phase

25. Arterial phase
Starting of arterial
filling and
continuation of
choroidal filling
1 second after
choroidal phase

26. Arteriovenous phase
(capillary phase)
– Complete filling of the
retinal arteries and
capillaries.
– early laminar flow of
the veins so dyes seen
along lateral wall

27. Venous phase
– Early venous phase.
– mid venous phase.
– Late venous phase

28. Early venous phase
Arteries and capillaries are completely filled and marked
lamellar venous flow

29. Mid venous phase
Some veins are
completely filled
Some shows marked
laminar flow

30. Late venous phase
All veins are completely filled and the arteries beginning to empty.

31. Late phase
( Elimination phase)
– Gradual elimination of dye from the choroidal and the retinal
circulation.
– Staining of the disc is the normal finding.
– Any areas of late hyper fluorescence suggest an abnormality
.Fluorescence is absent from angiogram after 5-10 minutes and is
usually totally eliminated from the body within several hours

32. FFA interpretation flow chart
fluorescein angiogram
normal abnormal artifact
hyperfluorescence hypofluorescence
Leakage pooling staining window blocked nonfilling
defect

33. Terminologies
– Fluorescence- ability of a compound to absorb light of
shorter wavelength and emit light of longer
wavelength with in a very short interval
– Hyperfluorescence – an area of abnormally high
fluorescence due to increase density of dye molecule
– Hypofluorescence - an area of abnormally poor
fluorescence
– Autofluorescence – an inherent property of a lesion
to spontaneously fluoresce even in absence of dye
( observed before injection of the dye)

34. – Control photograph –photo taken before dye given
to detect autofluorescence
– Arm retina circulation time- from dye injection to first
appearance in retinal arteries( 10-12 secs)
– Pooling- accumulation of dye in closed space .e.g. RPE
detachment, CSR
– Leakage- dye escapes in open space e.g. vitreous
space
– Window defect- type of early hyperfluorescence due
to RPE atrophy

35. – Staining- late hyperfluorescence due to adsorption of
the dye by a tissue
– Blocked fluorescence – hypofluorescence occurs by
masking underlying retinal and choroidal tissue by
blood , pigment etc.
– Capillary nonperfusion – due to non filling of the
retinal capillaries due to anatomical and function
reasons
– Artifacts- undesirable shadows that are seen
following the development of the film

36. Abnormal fluorescein
– Hyperfluorescence (white lesion)
– Hypofluorescence ( black lesion)
– Autofluorescence

37. Hyperfluorescence
Window defect- focal RPE atrophy
Unmasking of normal background of choroidal fluorescence
characterized by early hyperfluorescence which increases in
intensity then fade without changing shape and size
e.g. APMPPE, Serpiginous Choroiditis
inflammation of RPE
depigmentation and atrophy of RPE

38. Window defect

39. Pooling
Pooling ( accumulation of dye in a closed space)
sub-retinal space sub RPE space
-Early hyperfluorescence early hyperfluorescence
-increase in size ,intensity increase intensity only
e.g. CSR e.g. PED

40. – Causes-:
– At macula-:Cystoid macular edema, ect
– At Disc-: Papilledema, NVD , Ischemic optic neuropathy,
Inflammation
– Elsewhere -: NVE ,CNV, Vasculitis,PED

43. CSR ( increased size and intensity)

45. Leakage ( frank hyperfluorescence that
increase in size and intensity )
1) Abnormal choroidal vasculature
CNV
2) Breaking of inner blood-retinal barrier
Cystoid macular edema- flower Patel
3) Abnormal retinal or disc vasculature
NVD, NVE
Staining ( hyperfluorescence that is minimum in early and
mid phase and increasing in late phase)
Due to prolonged dye retention e.g. drusen

46. Causes of hyperfluorescence
Leakage of dye Prolonged dye retention
( staining)
Into sensory retina
(Cystoid macular edema)
From new vessels
(choroidal neovascularization)
Associated with drusen

47. Focal exudative
• Circumscribed retinal thickening
• Associated complete or incomplete
circinate hard exudates
• Focal leakage on FA

48. Diffuse exudative
•
• Diffuse retinal thickening
•Obliteration of landmark leads
to localization of FOVEA difficult
•
• Generalized leakage on FA

49. Cystoid macular edema

50. Hypofluorescence
Blockage Filling defect
1)Retinal fluorescence 1) vascular occlusion
Vitreous opacity ( choroidal, retinal artery
Pre-retinal hge vein or capillary)
2) Background choroidal fluorescence 2) loss of vascular bed
Sub retinal hge choroidermia
Increased RPE density myopia
Choroidal naevi

51. Choroidal nevus
Blockage of background choroidal
fluorescence

52. 2 ) Focal RPE hypertrophy

53. 3) Haemorrhage under RPE

54. Blocked fluorescence in CRVO

55. BRVO

56. • Macula appears relatively normal
• dark blot hemorrhage
• Capillary non-perfusion on FA
• Enlargement of the FAZ
FILLING DEFECT
Diabetic macular ischemia

57. Ischemic CRVO

58. Eales disease
( peripheral ischemia)

59. NVE
Extensive
capillary dropout

60. Filling defect in CRAO

61. Limitations of FFA
1) Does not permit study of choroidal circulation details due to
a) melanin in RPE
b) low mol wt of fluorescein
how to overcome ---- ICG
2) More adverse reaction
3) Inability to obtain angiogram in patient with excess hemoglobin or
serum protein.e.g.
polycythemia
weldenstrom macroglobulenaemia
binding of fluorescein with excess Hb or protein
Lack of freely circulating molecule

62. autofluorescence
– Innate property of fluorescein in certain ocular tissue
– Fluorescein without dye
– It is exhibited by
– Crystalline lens, basement membrane, myelinated nerve
fibers, melanin granules ,certain lipids

63. Autofluorescence
Optic nerve head drusen

64. Stepwise approach to
reporting FFA
1) Comment on red free photograph
2) Is the abnormality black or white?
3) Indicate the phase of angiogram
4) Indicate any characteristic feature as smoke stag
5) Are the retinal vessels filling normally?
6) Indicate any change in area or intensity of
fluorescence
N.B : patient’s history and clinical co relation should
always be done before drawing conclusion from
the FFA

65. Recent Advances
– Imaging angles greater than 50 degrees is termed as “wide
field imaging” and greater than 100 degrees have been
termed as “ultra wide field imaging”.
– NEED FOR WIDE FIELD IMAGING:
– The peripheral retina is the site of pathology in many
vision- threatening eye diseases.
– Evaluation of the retinal periphery, therefore, is important
for screening, diagnosis, monitoring, and treatment of
disease manifestations.

66. – VARIOUS TECHNIQUES:
– CLASSIC fundus camera
– POMERANTZEFF camera
– RETCAM
– PANORET
– STAURENGHI LENS SYSTEM
– SPECTRALIS
– OPTOS

67. HEIDELBERG SPECTRALIS-
– Uses a noncontact removable lens that attaches onto the
camera head of the Heidelberg HRA CSLO which greatly
expands the viewing angle capabilities from a previous
maximum of 55° to the UWF range 105 .

68. OPTOS
– Imaging capabilities with OPTOS:
– Wide field (200 degrees) fundus imaging
– Fluorescein angiography of retinal periphery (488 nm laser,
barrier - 500 nm)
– Autofluorescent imaging of retinal periphery(532 nm for
excitation and 570-780 emission filter)
– More recently infrared 805 nm wavelength with a barrier
filter -835 nm has been added for ICGA

69. OPTOS
– ADVANTAGES:
– Obviates the need for contact lens
– Pupillary dilatation not required
– Fast imaging speed( A single monochromatic scan requires 0.25 sec to
perform)
– High resolution(20 pixel resolution per degree)
– Customizability with various lasers and filters
– Permits in focus imaging from ant retina to PP and even into deep
staphyloma

70. – CLINICAL USES:
– Diabetic retinopathy
– Retinal venous occlusions
– Choroidal masses
– Uveitis
– Retinal vasculitis
– Choroidal dystrophies(Gyrate,choroideremia)
– Retinal detachment
– Pediatric retinal diseases

74. LIMITATIONS
 Incapable of imaging ora to ora and can still miss anterior retinal pathology
 Fails to image superior and inferior retina more frequently than nasal and
temporal
 Distortion and decreased resolution of peripheral retina
 Measurement of distance and area on the images may not correspond to the
actual dimensions of the eye(Recently introduced a stereographic projection
software algorithm-maintains same angular relationship at every eccentricity)
 Image contrast is not uniform across the fundus.
 Does not allow retinal view before taking the image.
 Artifacts produced by eyelashes, native lens,intraocular lens, pigments in the
anterior segment and vitreous opacities

75. ICGA
ICG FFA has limited applications for
choroidal imaging due to-:
 Masking of choroidal circulation by
ocular pigments and blood.
 Rapid leakage from choriocapillaris masking
the choroidal vasculature.

76. Properties
 Water soluble tricarbocyanine dye.
 Contain 5% sodium Iodide.
 Absorption – 805nm
 Emission – 835nm
 98% protein – binding
 excreted exclusively by the liver
 Dosage 25mg/2ml followed by 5ml bolus saline

77. Adverse Reactions
 Mild
 Nausia,Vomiting,Pruritis
 Moderate
 Urticaria, syncope, skin eruptions, pyrexia, local tissue
necrosis, nerve palsy.
 Severe
 RS - Bronchospasm, Laryngospasm and anaphylaxis
 CVS - Circulatory shock, myocardial infarction and arrest.
 CNS - Tonic-clonic seizure

78. FFA Vs ICG
PARAMETERS FFA ICG
1) Dye used Sodium fluorescein Indocyanine green
2) Light used visible spectrum infrared
3) purpose study retinal
vasculature
Choroidal
vasculature
4) Filter used Blue- green Infra-red
5) expense lower higher