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fundus flourescien angiography

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Fundus Fluorescein Angiography Vasiur Rahman Phase-III
Transcript

Fundus Fluorescein

Angiography

Vasiur Rahman

Phase-III

FFA

• technique for examining the circulation of

the retina and choroid using a fluorescent

dye and a specialized camera.

Purpose

• Highlight retinal and choroidal circulation

• Detect early vascular pathologies

• Confirm diagnosis

How does it work?

Charateristics applications

• Absorbs 465-490nm,

emits 520-530nm

• Binding to plasma

proteins, esp Albumin

• Selective visualization of

its passage

• Confined to natural blood

retinal barrier

• Based on luminescence.

– Fluorescence

– phosphorescence

• Exciter filter

– Allows only blue light to illuminate

retina(wavelength of 490 nm)

• Barrier filter

– Allows only yellow-green light (from the

fluorescence) to reach the camera

wavelength 525 nm)

P

Dosage and Administration

• It is performed by injecting fluorescein

sodium dye as a bolus into a peripheral

vein. The normal adult dosage is 500mg,

and is typically packaged in doses of 5 ml

of 10% or 2 ml of 25%.

The sequence:

passage of dye after inj.Visualization

• 10 to 15 sec : Short posterior ciliary arteries.

• Choroidal flush, optic nerve head, cilioretinal

artery.

• 11-18 sec: Retinal circulatiion, arteries-capillaries-

veins.

• 20-25 sec: juxtrafoveal and perifoveal capillaries

Maximal fluorescence around FAZ. The best time

for PEAK PHASE IMAGING.

• 30 sec: First passage completed. Recirculation

starts

• After 10min: total disappearance of dye.

• A. (preinjection) With exciter and barrier in place, the

featureless black control photograph reveals either

the presence or absence of auto- and

pseudofluorescence.

• B. (0 secs after injection) The tran-sit phase begins

with choroidal filling.

• C. (10 secs) Described as patchy, the transit phase is

simultaneous with the filling of cilio-retinal arteries

• D. (12 secs) The retinal arteries are infused.

• E. (15 secs) The dye returns via the retinal

veins. Note the laminar flow during the

arteriovenous phase

• F. (about 30 secs) The angiogram is brightest

and microvasculature most visible.

• G–I. (5 and 10 mins) As the fluorescein

dye diffuses through the tissue, contrast

decreases and the optic nerve head stain

The Interpretation

Hypo-fluorescenceHyper-fluorescence

• Blocked: Media opacity,

Hem

• Vascular Filling Defects:

Occlusions, capillary non

perfusion

• Autofluorescence

• Transmitted fluorescence

• Hyperfluorescence:

• 1. Abnormal Vessels:

Angiomas, Tumours

• 2. Leakage:

• 3. Pooling: CSR, PED

• 4. Staining: Disc, drusen,

chorioret. scar

Transmitted fluorescence

Window defect

Tearing of RPE

Diabetic retinopathy

Macular degeneration

• (A) Color

• (B) red-free

• (C) photgraphs of a fundus with soft drusen and hyperpigmentation. Soft drusenhyperfluoresce during the early phase of angiography (D)stain in the late phase

choroiditis

• Red-free photo, early

arteriovenous phase, peak phase ,

and late phase angiogram of a left

eye with choroiditis. Early

angiogram demonstrates

hypofluorescence of the choroidal

lesions with the development of

circumferential hyperfluorescence

and leakage in the later stages of

the angiogram.

Central Serous

retinopathy

Color fundus photograph

(A) and corresponding

fluorescein angiography

images,

(B) early, (C) mid, (D) late

phase

showing ink blot type of

RPE leak

• Fluorescein angiogram showing intense hyperfluorescence created by the window defect after a retinal pigment epithelial tear. The hypofluorescence corresponds to the area where the pigment epithelium rolled together in accordion fashion

BRVO

Late arteriovenous phase

demonstrates leakage from the

supertemporal retinal vessels

Late arteriovenous or laminar

venous phase angiogram in a

patient with a superotemporal

branch retinal vein occlusion.

Hypofluorescence is noted along

the superotemporal arcade

CRVO

Be aware-

• nausea, vomiting, acute hypotension, anaphylaxis

• Cardiac arrest

• Death

• The most common adverse reaction is nausea, due to a difference in the pH

• 25 times higher if the person has had a prior adverse reaction

• The risk can be reduced with prior (prophylactic) use of antihistamines

• Premedication with promethazine

hydrochloride or proclorperazine may

prevent or lessen the severity of nausea

and vomiting in patients with a history of

previous reactions to fluorescein

• Extravasation

• pruritus or urticaria can be treated with

antihistamines

• More severe reactions are rare, but

include laryngeal edema, bronchospasm,

anaphylaxis, tonic-clonic seizure,

myocardial infarction and cardiac arrest.

The overall risk of death from fluorescein

angiography has been reported as 1 in

222,000.

Yannuzzi LA, Rohrer KT, Tindel LJ, et al. Fluorescein angiography complication survey. Ophthalmology 93:611-617, 1986.

During Pregnancy and

Lactation

• Controversial

• Fl. Crosses the placenta

• Has been done in pregnancy with no adverse effect

• Do it when necessary


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