The FDA is the United States government agency responsible for the evaluation and approval of medical devices. Fovea is the region of the retina with the highest concentration of special retinal nerve cells, called cones, that produce sharp, daytime vision. Glaucoma is an eye disease in which the normal fluid pressure inside the eyes slowly rises, leading to vision loss or even blindness. Ghost Image is a fainter second image of the object you are viewing. Glare is scatter from bright light that decreases vision.
Halos are rings around lights.
Haze is corneal clouding that causes the sensation of looking through smoke or fog. Hyperopia is the inability to see near objects more clearly than distant objects. Inflammation may be caused by mechanical trauma, infections, bacteria, viruses, immune reactions or other causes. Iris is the colored ring of tissue suspended behind the cornea and immediately in front of the lens. Keratectomy is the surgical removal of corneal tissue.