Fundus Fluorescein Fundus Fluorescein AngiographyAngiography

PHYSICAL PRINCIPLESPHYSICAL PRINCIPLES

• Luminescence- Emission of light from any source other then high temp.

• Fluorescence- luminescence maintained only by continuous excitation. (stop as soon as exciting stimulus withdrawn)

FFAFFA

PURPOSE

• Evaluate, Diagnose -Retinal, Choroidal vascular & Macular diseases

• Guide - for laser treatment

• Monitor-effect of treatment

HISTORYHISTORY• 1871-Adolf Baeyer-first to synthesize dye

Na. Fluorescien

• 1910-Burke examine the Retina & choroid after administration of fluorescien in coffee

• 1925-Nordenson –fundus camera

• 1961-Novotny & Alvis- First Successful FFA in human.

TECHNIQUETECHNIQUE• seated in front of fundus camera

• Color & Red-free image is capture

• Fluorescein dye 5ml of 10% or 3ml 25%(for opaque media) injected.

• Images taken approx 1-sec intervals ,5-12 sec after inj.

• After transit phase photograph in one eye control picture of opposite eye.

• Flourescene enters in the eye through ophthalmic artery

• Passing into the choroidal circulation.-post ciliary A.

• Retina-central retinal a.

PHASES OF ANGIOGRAMPHASES OF ANGIOGRAM

• Choroidal (10-12 sec)

• Arterial (1-3 sec)

• A-V (capillary)

• Venous (20-25 sec)

• Recirculation(30 sec )

• Late phase(10 min)

CHOROIDAL (PRE-ARTERIAL) CHOROIDAL (PRE-ARTERIAL) PHASEPHASE

Early choroidal fluo is faint patchy & irregular-choroidal flush

• Area of filling & nonfilling distinct – patchy choroidal filling

• Cilioretinal a. fills

ARTERIAL PHASEARTERIAL PHASE

Filling of CRA.

EARLY A-V PHASEEARLY A-V PHASE• Dye from smaller venules enter

the vein along their wall-laminar flow

• Dye sticks to the wall of vein• At the junction of two

vein ,inner lamina of each merge creating a trilaminar flow

A-V PHASEA-V PHASE• Dye completely fill the lumen of vein

• Perifoveal capillary network best visualized (dye max concentration)

• Fovea appears hypofluo.

RECIRCULATION PHASERECIRCULATION PHASE

• Begins about 30 sec of dye inj

• Dye in lower concentration

LATE PHASELATE PHASE• Vessels are empty(10 min after inj)• Diffuse background fluo (d/t staining of

bruch’s memb. choroid & sclera )• Large vessels seen in silhouette against

this background• Disc remain hyperfluo in late film

(staining)

WATERSHED ZONEWATERSHED ZONE• Post ciliary a. supply the lat. & medial halves

of disc & choroid • Four (sometime 6-7) post ciliary vein (vertex

vein) drain into sup. & inf ophthalmic veins • quadrantric pattern • Segmental drainage exists vertical &

horizontal watershed• FA-patchy choroidal filling

DARK APPEARANCE OF DARK APPEARANCE OF FOVEAFOVEA

• Avascularity of FAZ

• Blockage of choroidal flurescene (xanthophyll)

• Blockage of choroidal flurescene (larger RPE , more melanin)

ABNORMAL FLUORESCENCEABNORMAL FLUORESCENCE

• d/t LEAKAGE

(a) Abnormal choro.vasculature-CNV Early lacy filling pattern

which increase in size & intensity

b)(Breakdown of inner retinal barrier-CME

• Beginning of A-V phase which increase in size and intensity

• Flower-petal pattern (late phase)

(c) Abnormal retinal or disc vasculature- PDR

HYPERFLUORENSCENCE HYPERFLUORENSCENCE D/T POOLINGD/T POOLING

• Dye in anatomical space d/t breakdown of outer retinal barrier(RPE tight jn)

(a) In the sub-retinal space-

Early hyperfluo which increase in size and intensity-CSR

CSRCSR

(b) In the sub-RPE space- PED

early hyperfluo which increases in intensity but not in size

STAININGSTAINING• Attachment of the dye molecule to tissue • May be seen in late phase of angiogram• It occur in normal structure (sclera) or pathological

states (Scar ,drusen)• Margins do not go beyond

TRANSMISSION (WINDOW) TRANSMISSION (WINDOW) DEFECTDEFECT

• Seen –focal RPE atrophy Or absence• Unmasking of normal choroidal fluo.• Early hyper-fluo. Increases in intensity & then

fades in late phase without changing size or shape

CAUSES OF CAUSES OF HYPOFLUORESCENCEHYPOFLUORESCENCE

• Reduction or absence of fluo.

(a) Blockage(masking)-retinal / choroidal

(b) Filling defects

BLOCKAGE OF RETINAL BLOCKAGE OF RETINAL FLUORESCENCEFLUORESCENCE

1-vit.opacities & Pre-retinal lesion-blood

-Block all fluo.

2 deep retinal lesions –intra-retinal h’age & HE

-Block only capillary fluo. Sparing large retinal vessels

BLOCKAGE OF CHOROIDAL BLOCKAGE OF CHOROIDAL FLUORESCENCEFLUORESCENCE

1-sub-retinal/ Sub-RPE lesion-blood

2-incease density of RPE- congenital hypertrophy of RPE

3- choroidal lesion -naevi

FILLING DEFECTSFILLING DEFECTS

1-Vascular occlusion-prevent access dye to the tissue

Occlusion may choroidal circulation / retinal a./r.vein/capillaries(capillary drop out)

2 loss of vascular bed-severe myopic deg or choroideremia