Visual Field Testing

Confrontation is the bedside procedure for visual field testing

Perimetry is the test for confirmation of Field of vision though it can test the peripheral field best( Excluding the central 30 Degree of vision).

Depending wether the stimulus moves or not the perimetry is of 2 types.

1. Static permetry - Eg: Humphry field analyzer

2. Kinetic perimetry - Eg: Goldmann's perimetry

The field of vision is plotted by plotting points along circles known as Isopters 

Bjerrum screen is used for testing the central field of vision (about 50º in diameter)

It consists of dull black cloth or other material perpendicular to the line of sight and placed usually 1 m away from the subject (2 m gives more accuracy).  In the centre of the screen is a white spot (white 1 mm pinhead)  that provides a fixation point and a series of radial and circumferential lines are sewn or drawn to facilitate the localization of the stimulus