Postoperative aqueous humour flare as a surrogate marker for proliferative vitreoretinopathy development

As some surgical procedures have been shown to increase postoperative flare values and thus contribute to blood-ocular barrier breakdown, retinal reattachment surgery might influence the risk of developing proliferative vitreoretinopathy (PVR). Therefore, we investigated whether postoperative aqueous flare values are a surrogate marker for the development of postoperative PVR.

We prospectively included 195 patients with primary rhegmatogenous retinal detachment (RRD) and measured aqueous laser flare preoperatively, and at 2 and 6 weeks postoperatively. Postoperative PVR was defined as reoperation for redetachment due to PVR membranes, within 6 months of initial surgery. Logistic regression and receiver operating characteristic (ROC) analysis determined whether higher postoperative flare values were associated with an increased risk of developing PVR later on.

Reoperation for postoperative PVR was needed in 12 (6.2%) patients; in 18 (9.2%), reoperation was not related to PVR. The median flare value for patients who would develop PVR was significantly higher than that of patients who would not develop PVR, both at 2 weeks (p = 0.001) and 6 weeks (p < 0.001) postoperatively. Logistic regression analyses showed that a higher flare value significantly increased the odds of developing PVR, either at 2 weeks [odds ratio (OR) 1.027; 95% CI: 1.010-1.044] or 6 weeks (OR 1.076; 95% CI: 1.038-1.115).

Flare values both at 2 and 6 weeks postoperatively seem a good surrogate marker in terms of sensitivity and specificity for the development of postoperative PVR but have only a modest positive predictive value. The 2-week value would be more useful in terms of early recognition of high-risk patients and hence give the possibility to better study effects of treatment methods.