Hemispheric dome and bucket method of subjective visual vertical testing

The bucket method for determining monocular and binocular visual vertical: patients sit upright looking into a translucent plastic bucket so that the bucket rims prevent any gravitational orientation clues. On the bottom inside the bucket there is a dark, straight, diametric line. On the bottom outside there is a perpendicular that originates from the center of a quadrant divided into degrees with the zero line corresponding to the true vertical. For measurement, the examiner rotates the bucket clockwise or counterclockwise to an end position and then slowly rotates it back toward the zero degree position. Patients indicate the position where they estimate the inside bottom line to be truly vertical by signaling stop. The examiner reads off the degrees on the outside scale. A total of 10 repetitions are performed. An eye patch is used for monocular testing.