Threshold-adjusted supraliminal pattern perimetry with the Goldmann perimeter

Abstract

This paper describes a method of supraliminal pattern perimetry for use with a Goldmann perimeter. In this method, the stimuli are adjusted in stages in accordance with the normal physiological sensitivity gradient. The threshold is determined on four meridians located 10 degrees and 30 degrees from the center. These threshold values are used to define three different levels of brightness which exceed the threshold by approximately the same amounts in three sectors of the field of vision extending from 2 degrees to 10 degrees, 10 degrees to 20 degrees and 20 degrees to 30 degrees. The points arranged in a rectangular pattern at intervals of 3 1/3 degrees are used to check for relative and absolute defects in the patient's field of vision. Supraliminal pattern perimetry can be performed manually on the Goldmann perimeter in a manner similar to automatic supraliminal perimetry to detect small defects in the field of vision. Manual perimetry, though, allows the physician to use his clinical experience directly and also makes it possible to combine screening and detection into a single procedure, since it is then possible to alter pattern density and to switch from supraliminal pattern perimetry to kinetic and free static threshold determination during the actual course of the examination. The flexibility of the manual method may well save both physician and patient time and effort, especially in difficult cases. With automatic perimetry, however, such flexibility is hampered by the fact that programs must be run through in succession (with the exception of the Octopus Program 4).