After analyzing a series of 10 visual fields in 262 patients for visual field progression in bilateral glaucoma, a recent study found that the rate of progression in the fellow eye predicts the long-term rate of VF change in the eye examined. The researchers noted that apparent rapid progression in an eye is more likely to be real if the fellow eye also appears to be rapidly progressing.

The study determined visual field progression rates by analyzing the mean deviation (MD) over time and studied whether incorporating the fellow eye’s level of visual field damage or rate significantly improved the models.

For short series (n=three to four visual fields), incorporating rate information from the fellow eye, but not the level of damage in the fellow eye, significantly improved the researchers ability to predict the rate over the entire 10 fields. However, the fellow eye’s rate of change was no longer useful in predictions for five or six fields.

“The long-term rate of visual field change in an eye is, in part, predicted by the rate in the fellow eye, particularly when only a few visual fields are available for each eye,” the researchers conclude in their paper.