Perimetry is the systematic measurement of visual field function. The two most widely used types of perimetry are Goldmann's kinetic perimetry and threshold static automated perimetry. With Goldmann or "kinetic" perimetry, a trained perimetrist moves the stimulus; the brightness of the stimulus remains constant. The limits of the visual field are assigned to lights of different sizes and brightness.
With automated threshold static perimetry, a computer program is selected. The most widely used tests the central 30 ° of the visual field using a grid spaced six degrees. This is accomplished by keeping the size and location of a target constant and varying the brightness until the dimmest target that the patient can see at each of the test locations is found. These visual sensitivity maps, produced by any of these methods, are very important in the diagnosis of diseases of the visual system. Different patterns of visual loss are found with diseases of the eye, central nervous system of the optic nerve.
There are four types of perimetry:
Reunión virtual con el Dr. Julian Triviño (Colombia)