2. What is F.F.A?
fundus fluorescein angiography (FFA) is a
technique for examining the circulation of
the retina and choroid (parts of the fundus) by using a
iv fluorescent dye and a specialized angiographic
camera.
4. Dye used in FFA
Refers to fluorescein sodium (C20H10Na2O5).
First synthesized in 1871 in Germany by Von Bayer.
A brown or orange-red crystalline substance, alkaline in nature.
Stable, Highly Water Soluble & Pharmacologically inert.
Fluoresces at Blood Ph.
80% bound to plasma protein and also with RBC.
Absorbs blue light (490nm ) and emits yellow-green light
(530nm).
Metabolized by liver and exerted by kidney
5. 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
6. Therefore ,FFA helps
In clinical diagnosis of choroidal and retinal disease
To determine extent of damage.
To formulate treatment strategy.
To monitor result of treatment.
7. Indications of FFA
Indications
of FFA
Retinal vascular
malformation and
tumor
Retinal
vascular
disorders
Macular
disorders
Choroidal
disorders
Optic
nerve
disorders
8. Retinal vascular disorder, malformation
and tumors
1) Diabetic retinopathy.
2) Retinal vein occlusions.
3) Retinal artery occlusion.
4) Retinal vasculitis.
5) Coats disease.
6) Familial exudative vitreoretinopathy.
7) Capillary hemangioma of retina.
8) Cavernous hemangioma of retina.
9) Retinal AV malformation.
10) Congenital tortuosity of retinal vasculature.
11) Congenital hypertrophy of RPE.
12) Angioid streaks.
13) Astrocytic hamartoma.
12. 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)
13. PROCEDUREPatient is informed of the normal procedures, the side effects and the adverse
reactions.
Dilating the pupil of pt. and Made to sit comfortable
3-4 red free photographs taken. (control photographs)
5ml of 10% or 3ml of 25% NAF injected through the anticubital vein
wait for 10 – 12 seconds( normal arm-retina time)
Photos are taken at 1 second interval for 10 seconds
Then every 2 seconds interval for 30 seconds
Late photographs are usually taken after 3 ,5 and 10 minutes.
14. CIRCULATION OF DYE
Dye injected from peripheral vein
venous circulation
heart
arterial system
INTERNAL CAROTID ARTERY
Ophthalmic artery
Short posterior ciliary artery) Central retinal A.
(choroidal circulation.) ( retinal circulation)
15. Types of circulation in fundus
A.Choroidal
circulation
-choriocapillaries are
fenestrated
-so allows dye to
diffuse freely
BUT,
-outer blood-retinal
barrier in RPE don’t
let dye to reach
retina
B.Retinal circulation
-endothelial cells of
retinal blood vessels
joined by tight
junctions (inner
blood retinal barrier)
-prevents leakage of
dye from vessels
16. Phases of angiogram
A) Choroidal (pre-arterial) -
B) Arterial
C) Arteriovenous(capillary)
D) Venous and
E) Recirculation (elimination)-
Patchy filling
No leakage
No complication
17.
18. 1.Prearterial/choroidal phase
8-12 seconds after dye
injection
Initial patchy filling
followed by diffuse
filling
No dye has entered
retinal circulation
19. 2.Arterial phase
Shows arterial filling
Continuation of
choroidal filling
1 second after
choridal phase
24. 5.Late/elimination phase-
Elimination of dye
from choroidal and
retinal circulation
Staining of disc –
normal
In 5-10 minutes
fluorescein absent
from angiogram
25. FFA interpretation
FFA should be
Normal Abnormal Artifact
Hyperfluorescence Hypofluorescence
Leakage Pooling Staining Window Blocked Non
filling defect filling
d/t increased accumulation of dye
26. Window defect-
Defect in RPE – increased
transmission of choroidal
fluorescence.
Sharply defined
hyperfluorescence
area. Window defect- large
Macular hole
30. POOLING
1. In sub Retinal space
- As in CSR
2. In sub RPE space
- As in PED
31. STAINING -Accumulation of fluorescence within a tissue
-Due to prolonged dye retention
-Can be seen in normal as well as pathologically
altered tissue
RETINAL
a. Non-cystoid macular
oedema
b. Perivascular staining
SUB RETINAL
A. Drusens
B. Sclera
C. Lamina cribrosa
D. Scars
Examples are-
ARMD
32. Hypofluorescence
Reduction or absence of
fluorescein
Two causes-
1. BLOCKED
FLUORESCENCE
2. VASCULAR
FILLING DEFECTS
A. Optical obstruction (masking)
of normal density of fluorescein.
B. Caused by lesions anterior to
retina
A. Inadequate perfusion of tissue
with resultant low fluorescein
content
33. BLOCKED FLUORESCENCE EXAMPLES ARE
Pre-retinal lesions eg.vitreous
opacity,preretinal
haemorrhage block all
fluorescence
Deep retinal lesions
eg.intraretinal haemorrhage
and hard exudates block only
capillary fluorescence
Increased density of RPE
eg.congenital hypertrophy
Choroidal lesions eg.naevus
RPE hypertrophy
34. Examples of Filling defects-
Avascular occlusion of choroidal circulation or
retinal arteries,veins and capillaries
Loss of vascular bed eg.severe myopic degeneration –
choroideremia
Emboli
arteriosclerosis
36. Fovea in FFA(FAZ)
Appears dark
d/t
AVASCULARITY
in fovea
BLOCKAGE OF
CHOROIDAL
FLUORESCENCE
INCREASED
XANTHOPHYL
PIGMENTS
LARGER RPE
CELLS WITH
MORE
MELANIN
38. Complications of FFA
MILD
Staining of skin,
sclera and mucous
membrane
Stained secretion
Tear, saliva
Vision tinged with
yellow
Orange-yellow
urine
Skin flushing,
tingling lips
pruritis
MODERATE
Vasovagal response
Utricaria
Fainting
Periphlebitis
Nausea and
vomiting
SEVERE
Respiratory-
laryngeal edema
,bhroncospasm
Circulatory shock,
MI, cardiac arrest
Generalized
convulsion
Skin necrosis
39. Limitations of FFA
1) Does not permit study of choroidal circulation details due to
a) melanin in RPE
b) low mol wt of fluorescein
2) More adverse reaction
3) Inability to obtain angiogram in patient with excess hemoglobin
or serum protein.e.g.
- polycythemia
-weldenstrom macroglobulenaemia
bcz binding of fluorescein with excess Hb or protein so ,Lack
of freely circulating molecule
40. OPHTHALMIC ULTRASOUND
What is ultrasonography?
- Non-invasive imaging by
using ultrasonic wave
(Piezoelectric Effect)
- 1942 – Neurologist Karl
Dussik is credited with
being the first to
use sonography for
medical diagnoses
41. Frequency uses in ocular scan
Low frequency (3-5 MHz)
Use for orbital tissue pathology
Medium frequency (7- 10 MHz)
Retina , vitreous, and optic nerve pathology
High frequency (30-50 MHz)
For Ant. Chamber pathology
42. Type of scan
A-Scan (by using
single beam)
B-Scan (by using
multiple baem)
44. B-scan
Baum and Greenwood in 1950’s
developed B scan
Mainly 3 types of probe position-
A)Transverse section
B) Longitudinal section
C)Axial section