Prostaglandin E2 level in tears during postoperative inflammation of the eye

The concentration of prostaglandin E2 (PGE2) in tears was measured by a radio immuno assay technique in 25 persons before cataract extraction and during the post-operative period. In addition we studied the clinical signs of inflammation, the tear secretion rate, the content of polymorphonuclear leucocytes (PMNs) in tears, the bacteriology of the conjunctival sac and the central corneal thickness (CCT) during this period. We found pre-operative median level of PGE2 of 82 pg/ml and on the first post-operative day a significant rise in PGE2 concentration despite increased tearing. There was a tendency towards further gradual increase in PGE2 concentration until the 5th day and thereafter a decline to pre-operative level 12 days after surgery. The conjunctiva is proposed as a possible source of the PGE2 in tears. No significant correlation could be demonstrated between PGE2 levels and clinical signs of inflammation, CCT, PMN level, bacteriology or tear secretion rate.