A fluorescein dye disappearance test is used in children and adults to find out whether tears are draining normally from the eyes into the nose.
One drop of a special dye (fluorescein) or a paper strip containing the dye is placed between the eyelid and the eye.
After 10 to 15 minutes, the doctor looks in your eye using a blue light. The light can detect very small amounts of fluorescent dye. The doctor may also use the light to look in your throat and inside your nose.
Normally, tears sweep the dye out of the eye and into the tear ducts. If dye stays in the eye, the tear duct may be blocked.
Periodic comprehensive eye exams by an eye doctor are essential to monitor the health of your eyes and diagnose suspected problems. Checking the position of each eye and its movements will reveal crossed eyes or other forms of strabismus. The exam may include these parts:
An eye chart uses letters of decreasing size to determine the sharpness of your vision at a distance.
The retinoscope projects a thin beam of light into the eye. When used with the rotating lens dial (called...