Patient Care

Fundus Photography

Fundus photography is a highly specialized form of medical imaging, it can’t be done with an ordinary camera.  It requires a customized camera that is mounted to a microscope with intricate lenses and mirrors.  These high-powered lenses are designed so the photographer can visualize the back of the eye by focusing light through the cornea, pupil and lens. 

Before beginning, the pupil is dilated with drops. Otherwise, it would automatically constrict from the bright light of the camera flash.  The patient is asked to stare at a fixation device so the eyes are still.  While the photographer is taking the pictures, the patient will see a series of bright flashes.  The entire process usually takes approximately five to ten minutes.

This is an important test to evaluate a variety of retinal disease such as diabetic retinopathy. This is one of the commonest tests performed for retinal diseases. The test involves injecting a dye called sodium fluorescein into the blood stream and taking photographs of the retina using special filters. The test is important to stage the disease as well as to guide treatment with laser photocoagulation. Present generation digital cameras permit manipulation of the pictures and for instant viewing without need for development of the film etc.

Indocyanine angiography is similar to the fluorescein angiography but involves injection of a different dye called Indocyanine green. The test utilizes a special infrared sensitive camera to capture the images digitally. Very often indocyanine and fluorescein angiography are combined in a given patient to give maximum information. Indocyanine angiography gives more information regarding the choroidal vessels compared to fluorescein angiography that gives more information regarding the retinal blood vessels.

These two tests are done to evaluate the function of the retina. Light is projected onto the retina and electrical potentials that occur normally in the eye are recorded using special electrodes placed near and on the eye. Certain retinal degenerative diseases are diagnosed only on testing with electroretinography. Specialized computer soft ware is needed to analyze the data.