Clinicopathological correlation of epiretinal membranes and posterior lensopacification following perfluorohexyloctane tamponade

Background/aims-Epiretinal and retrolental proliferation may occur during p rolonged use of the novel tamponade agent perfluorohexyloctane (F6H8). This study aims to determine whether there is any histological evidence that F6 H8 has a role in the formation of these membranes. Methods-Eight epiretinal membranes and three opaque posterior lens capsules were excised from patients in whom F6H8 had been used as a long term retin al tamponade agent. The membranes and capsules were examined employing ligh t microscopic methods, including immuno-histochemistry. Results-The epiretinal membranes showed histological features typical of pr oliferative vitreoretinopathy (PVR) epiretinal membranes, but they also exh ibited a dense macrophagic infiltration. In addition, three of the membrane s contained multinucleated cells. Macrophages represented up to 30% of the cells present and appeared to contain large intracytoplasmic vacuoles, Simi lar cells were seen on the back of the posterior lens capsule in one specim en and all three capsules had posterior migration of lens epithelium. Conclusion-The pathological findings are not simply those of PVR. The macro phage infiltration suggests that there may be a biological reaction to F6H8 which could reflect its surmised propensity to emulsify. Further investiga tions concerning the cellular response to this promising tamponade agent ar e warranted.