Postoperative fibrin formation and visual outcome after pars plana vitrectomy

To determine whether postvitrectomy fibrin formation was associated with visual outcome, a prospective study of patients undergoing pars plana vitrectomy was performed.

In 121 patients undergoing vitrectomy at the Medical College of Wisconsin between July 1986 and April 1989, the association of fibrin formation and other perioperative factors with visual outcome was evaluated by univariate and multivariate regression analysis. Poor visual outcome was defined as visual acuity worse than 5/200.

After a median follow-up period of 23 months (range 6 to 51 months), patients with severe fibrin formation experienced a higher rate of poor visual outcome (19 of 26 patients, 73%) than patients with little or no fibrin formation (23 of 95 patients, 24%; P < 0.0001, univariate analysis). After adjusting for a variety of factors with multivariate regression analysis, fibrin formation was not significantly predictive of final visual outcome.

Factors associated with postvitrectomy fibrin formation may affect visual outcome more than fibrin formation itself.