Is pupillary dilation affecting your automated perimetry results?

The effects of active pupillary dilation on automated static threshold perimetry were studied in twenty-three normal subjects using the Humphrey field analyzer and the 30-2, STATPAC, and FASTPAC programs. A decrease in foveal threshold of 1.95 decibels (P = 0.0081), a mean deviation loss of 1.15 decibels (P = 0.000 1), a decrease in short-term fluctuation (SF) of 0.19 decibels (P = 0.0423), and a decrease in the SF2 of 0.56 decibels (P = 0.0374) were found in dilated fields as compared with baseline visual fields in the first eye tested. A decrease in foveal threshold of 2.56 decibels (P = 0.0081) and a mean deviation loss of 1.43 decibels (P = 0.0001) were found in dilated fields as compared with baseline visual fields in the second eye tested. These findings indicate that active pupillary dilation in healthy subjects produces statistically significant differences, although these differences may not be clinically significant. To insure repeatable visual fields, consistent pupil diameter should be controlled in serial visual field testing