eye flourecein angiography

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Mohamed Abdel-Aziz (MSc,ICO,Egyption Board)

Mataryia Teaching Hospital

Fluorescence:

is the property of certainmolecules to emit light ofa longer wavelength whenstimulated by light of ashorter wavelength.

FFA

Characteristics of Fluorescein Alkaline solution

Highly fluorescent

Absorbs blue light (490 nm)

Emits yellow-green (530nm)

Removal from blood by kidneys and liver within24-48 hrs.

injection of 5 cc of 10% Na Fl, or 3 cc of 25%solution

FFA

Hazards Minimal relatively safe drug

Temporary tan skin color

Fl. Urine discoloration

Transient nausea and vomiting

Laryngeal edema

Rarely – Syncope, resp. or Cardiac arrest

Rx – I.V. Cortisone

A physician in the 1st few minutes

FFA

Anatomic Considerations

FFA

General principles of FA

Fluorescein• 85% bound to serum proteins• 15% unbound ‘free’ fluorescein

• Impermeable to fluorescein

Outer blood-retinal barrier (zonula occludens)

• Impermeable to fluorescein

Choriocapillaris

• Permeable only to ‘free’ fluorescein

Inner blood-retinal barrier(retinal capillaries)

Filters

1.Blue excitation filter

2.Yellow-green filter

FFA

Angiographic phases

Angiographic phases:

Five angiographic phases:

• Pre arterial (choroidal 9-15 seconds)

• Arterial

• Arteriovenous(capillary)

• Venous

• Recirculation

FFA

1-Choroidal flush 2-Arterial phase

3-Arteriovenous phase

4-Venous phase

Mid Phase Late Phase

Interpretation of FA

Red-free fundus photos

Normal appearance Autofluorescence

FFA

Abnormal angiographic findings

Hypofluorescence:

Filling defect

Blocking defect

Hyperfluorescence :

window defect

Leakage

Pooling

Staining

Hypofluorescence

Filling defect Inadequate perfusion of tissue (e.g:Vascular occlusion, Loss of the

vascular bed )

Blocking defect Masking of retinal fluorescence(e.g:intraretinal haemorrhages )

Masking of background choroidal fluorescence (e.g:naevi)

Hyperfluorescence

window defect Atrophy or absence of the RPE .e.g: as in atrophic age-

related macular degeneration, full-thickness macular holes

Pooling breakdown of the outer blood–retinal barrier (RPE tight

junctions)

A) In the sub-retinal space: increases in intensity and area, the maximum extent remaining relatively well-defined.(e.g:CSR)

Pooling B ) In the sub-RPE space: early hyper-fluorescence which

increases in intensity but not in size .(e.g:PED)

Leakage early hyper-fluorescence which increases in both area and

intensity

A) Dysfunction or loss of existing vascular endothelial tight junctions(e.g:CME)

Leakage B) Primary absence of vascular endothelial tight

junctions (e.g:CNV,PDR)

Staining prolonged retention of dye in tissue(e.g:drusen,

exposed sclera )

Systematic approach to reporting

angiograms

a- Patient's age and gender.

b-Right or left eyes.

c-Comment on any color and red free images.

d -Timing of filling, especially arm-to-

eye transit time.

e-Briefly scan through the sequence of images