Aqueous flare and cell number in healthy eyes of Caucasians.

A prospective study was conducted using the laser flare-cell meter to determine aqueous flare intensity and cell counts in normal Caucasian eyes and to investigate factors which may have an effect on these measurements. The factors included age, iris color, pupillary size and pharmacologic dilation. We also compared the measurements of flare and cells in the right versus left eyes of the same individual to determine whether any difference exists between the aqueous protein concentration or cell count of two normal eyes. Ninety-two healthy Caucasians (184 eyes) whose ages ranged from 21 to 79 years were enrolled in the study. We found that there was no significant difference between the flare and cell measurements of the right and left eyes. The flare intensity range in this study population was between 1.3 and 7.6 photon count/ms. Flare increased significantly with aging (r = 0.562, P = 0.000). The baseline anterior chamber cell number did not vary significantly by age in the 3rd to 7th decades. Only in the 8th decade did a significant increase in cell number occur. No correlation between the undilated pupil size and the amount of flare or cells was found. After pharmacological pupillary dilation, anterior chamber flare significantly decreased and cell number significantly increased. The flare-cell meter is a sophisticated and sensitive instrument used to assess the condition of the blood aqueous barrier, but for accurate evaluations, the patient's age and the pharmacologic dilation of the pupil must be taken into consideration.