Despite the relatively low rates of serious adverse events, informed consent should always be obtained prior to performing fluorescein angiography. No serious adverse events have been reported to occur in pregnancy however it is considered a contraindication. Death is estimated to occur in 1:221,781. Severe life-threatening reactions such as anaphylaxis, cardiac arrest, and bronchospasm do occur but are extremely rare. Local tissue necrosis can occur with extravasation of dye, however, mild pain and redness is more typical. More severe reactions such as urticaria, pyrexia, thrombophlebitis, and syncope are more rare. The most common reactions are transient nausea that occurs in 3-15% of patients, vomiting (7%), and pruritus. The images are recorded digitally or on 35mm film.Ī wide range of complications can occur with FA. Images are acquired immediately after injection and continued for ten minutes depending on the pathology being imaged. A barrier filter of 520-530nm allows capturing only light emitted from the excited fluorescein. Blue light (wavelength 465-490 nm) is then absorbed by unbound fluorescein molecules, and the molecules fluoresce, emitting light with a longer wavelength in the yellow-green spectrum (520-530nm). White light from a flash is passed through a blue excitation filter. Fluorescein dye is injected intravenously, usually through an antecubital vein with sufficient speed to produce high contrast images of the early phases of the angiogram. More modern advances such as digital imaging and computer software analysis have further enhanced the utility of the procedure.įA requires the use of a dedicated fundus camera equipped with excitation and barrier filters. John Donald McIntyre Gass began publishing his experience with FA in 1967 and his efforts led to the wider acceptance of the technique in the evaluation of retinal disease. Alvis, described and demonstrated the technique of retinal fluorescein angiography (FA) in 1961. Two medical students from Indiana University, Harold R.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |