(India)
Fluorescein Angiography is an important invasive Diagnostic tool for posterior segment eye surgeons for the evaluation of the retina and choroid.
A significant aspect in the retinal and choroidal study is a good visualization of it that allows us in correct interpretation of various pathologies for better medical, surgical and laser management of the diseases of the retina, choroid and optic nerve.
Fluorescein angiography with sodium fluorescein dye is an indispensable diagnostic procedure of great clinical significance. The specific physiochemical and the absorption emission characteristics of sodium fluorescein dye determines the features of fluorescein angiography. Chemically, it is xanthene derivative with a molecular weight of 376.27 which is large enough to prevent its passage across the tight barriers and at the same time is appropriate in allowing it to diffuse rapidly through fluid departments. Sodium fluorescein dye has unique features of ability to fluoresce (in visible spectrum), high solubility, greater binding to plasma proteins and erythrocytes enable it to be used in fluorescein angiography to evaluate the functional integrity of the outer and inner blood retinal barriers.
HISTORY OF EVOLUTION
Evaluation of fluorescein angiography has an unique and interesting aspect. In terminal part of 1950, a medical 3student Harold Novotny and Dr David Alvis working with Dr John Hickman (Head of Department of Internal Medicine of Indiana University) determined the oxygen saturation into the retinal arterioles for the first time.
Novotny struck with an idea of passing some kind of the dye through the circulating system to determine the oxygen saturation levels. He used sodium fluorescein for fluoroscence observation. Meanwhile Dr David Alvis used a mixed drop of its own blood with sodium fluorescein for fluorometric analysis. World's first fluorescein angiography was done on Dr David Alvis's right eye.
Novotny and Alvis sent their research work to American journal of ophthalmology in 1960 but the journal rejected it as lack of originality of work.
Miller and Chao, collaborators of Dr Maumenae also presented similar work. They presented their technique of fluorescein imaging in the association for the investigation in ophthalmology in April 1960. The first description of the fluorescein angiography technique appeared in the magazine officially in July 1961. In Spain also first article on fluorescein angiography (FA) was presented by Dr F Palomar Petit et al in 1969. It was published in archives of American ophthalmogical society.
This landmark work by Novotny and Dr David Alvis led to evolution of fluorescein angiography by several other related clinically works in USA and Europe over the time for the better refinement of FA technique alongwith development of more sophisticated equipments used in 4their technique for accurate and better assessment of various ocular pathologies.
In the present era of greater ophthalmological advances specially in last one decade, in the field of diagnosis, surgical and laser management, fluorescein angiography is an important diagnostic tool. Recent advances in FA specially CUE wide field fluorescein angiography, digital video angiography, high speed fluorescein angiography and 3D color Doppler video angiography have revolutionized the detection of pathologies of retina and choroid tremendously.
In this introductory chapter, I shall not go into various details of FA technique, procedures, indications, contra-indications and adverse effects as they have been nicely covered by International Masters of this field in the following chapters.
In this Mini Atlas, fluorescein angiography techniques have been shown in various posterior segment ocular pathologies specially in diabetic retinopathy, age related macular degeneration, retinal vascular occlusions, vitreous diseases, macular diseases. Inflammatory conditions and hemangiomas with short text and a large number of clinical and investigative figures to serve as Ready Reckoner for both anterior and posterior segment ophthalmologists.