Ophthalmic Diagnostic Photography
Fluorescein Angiography
A contrast medium called Sodium Fluorescein is injected into a vein in the arm. The dye
travels quickly through the body's circulatory system, and is photographed with black
and white film as it travels through the eye. The same camera which is used for fundus
photography is employed for this procedure. Two special filters are used to limit the
image to the color of light being emitted from the fluorescent dye.
About twelve seconds after the injection, the dye appears in the arteries of the retina. Over a
two to five second period, the dye travels through the very small vessels, or capillaries, and
fills the veins. Ten minutes after the injection, the dye has mostly evacuated from the eye,
having stained the optic nerve head.
This normal progression of dye is interrupted by many diseases of the choroid, retina, and
retinal vasculature. A fluorescein angiogram of a patient with ocular complications due
to diabetes (diabetic retinopathy) reveals vascular irregularities when compared with the
normal angiogram.
Fluorescein angiograms are used in the COMS primarily to determine the effects of
radioactive plaque treatment on vision in patients with medium sized tumors.
Read about Ophthalmic Echography
Review info about Color Fundus Photography
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