Fluorescein angioscopy is a procedure that is done with the help of an angioscope, which is a modified microscope used to study capillary vessels. It is done by using fluorescence which uses the property of certain substances to emit light on exposure to x -rays. Fluorescein angioscopy is done with the help of an indirect ophthalmoscope and it is used in the assessment, evaluation, and treatment of certain lesions in the eye, especially within the retinal periphery.
There are three techniques by which an angioscopy is done. One technique is called color angioscopy. It is done using a color filter, which in this case is cobalt blue. The person conducting the angioscopy carefully adjusts the cobalt blue filter so as to achieve a partial fluorescence through the microscope which shows a relation to the blue color and the retinal landmarks.
Angioscopy results can be preserved permanently by tracing the procedure and positions during different stages of the procedure with the help of tracing paper.
The blue filters from the dye pass over the coagulation beam and cause a blue image. The medical examiner can then identify the exact location of the lesion or coagulation in the retina of the eye.
In some cases, sodium fluorescence salt is used for fluorescein angioscopy. This compound is used mainly in the field of ophthalmology. Fluorescence sodium salt is an acidic yellow salt which looks yellowish green through a normal tear film and when it is in a more alkaline medium it appears brighter green. The alkaline medium is usually aqueous humor. The fluorescence of the salt enables the vascular area to be assessed to be lit up and demarcated so that it can be differentiated from the surrounding areas. The salt can be applied externally in the form of eye drops or can be injected into the vein near the eye for the procedure. It is used to diagnose and assess the extent of corneal trauma and corneal injury. Fluorescence sodium salt is used in the diagnosis of fundus and iris vasculature through the procedure of angioscopy.
Fluorescein angioscopy is a form of digital imaging that has become a medical standard for handling, storing, printing, and transferring information in medical imaging. This information is grouped into data sets. The images of a certain patient and the patient’s ID therefore, are linked together so as not to be separated or mixed up at all.