Purpose: To determine whether a consensual inflammatory response occurs following unilateral phacoemulsification or trabeculectomy in humans.
Methods: Sixty patients undergoing phacoemulsification or primary trabeculectomy were included in the study. Some patients were randomly assigned to have a shield placed on the non-operated eye during surgery. The Kowa laser flare meter (FM-500) and laser cell counter (LC-500) (Kowa Electronics and Optics, Tokyo, Japan) were used to assess the inflammatory response in both eyes. Measurements were taken preoperatively and on postoperative days 1, 7 and 28. The regression analysis with random model effect was used to identify factors which may affect the change of flare and cells in the non-operated eye after surgery. Correlation was evaluated between the inflammatory responses of the paired eyes. A P<0.05 was considered statistically significant for all analyses.
Results: The flare and cells in the non-operated eye showed a small, but significant, increase on day 1 (mean flare increased 2.68 photons/ms from preoperative level with P<0.001 and mean cells increased 2.49 cells/0.5 mm3 from preoperative level with P<0.0001). At day 7 the amount of inflammation was still elevated (mean flare increased 0.41 photons/ms from preoperative level with P<0.001 and mean cells increased 0.63 cells/0.5 mm3 from preoperative level with P<0.001). By day 28, the amount of inflammation in the nonoperated eyes returned to preoperative levels.
Conclusions: Subclinical inflammation occurs in the non-operated eye following phacoemulsification and trabeculectomy. The etiology of this finding has yet to be elucidated.