The art of perimetry.

There is no single method of perimetric examination which is applicable to all types of visual field defects. Perimetry is a subjective psychophysical sensory examination. It is not an exact science unless one includes the objective measurement of visual evoked response in the optic cortex. Until such a method becomes clinically available it will be necessary for the perimetrist to determine which techniques to use in a given case and to apply these techniques with sympathetic understanding. This is the art of perimetry.