Measurement of cellular proliferation within the vitreous during experimental proliferative vitreoretinopathy

Cellular proliferation is an important component in the pathogenesis of complex retinal detachments caused by proliferative vitreoretinopathy (PVR). We used flow cytometry to measure the proliferation of cells recovered from the vitreous cavity in an experimental model of tractional retinal detachment induced by homologous fibroblast injection. Two distinct populations of cells were detected. One population comprised smaller, dense cells representing mostly leukocytes. A second population of larger cells contained not only the injected fibroblasts but also high concentrations of host-derived cells with significant proliferative activity, whose number increased for 3 days following injection. Flow cytometry was useful for analysis of the recovered cells for concentration, morphologic features and proliferation. This technique may be applicable in the identification of patients at high risk for the development of PVR.