A PROSPECTIVE-STUDY OF MATRIX METALLOPROTEINASES IN PROLIFERATIVE VITREORETINOPATHY

PURPOSE. The migration, proliferation, differentiation, and adhesion o f cells and other cellular functions are influenced by the surrounding extracellular matrix, in normal and wound-healing conditions. The mat rix metalloproteinases (MMPs) are a family of enzymes that degrade and remodel the extracellular matrix and, thus, play a central role in th e wound-healing process. Proliferative vitreoretinopathy (PVR), a woun d-healing process in the retina, is a major cause of the failure of re tinal detachment surgery. The role of MMPs in the pathobiology of PVR is unknown. We have investigated the presence of MMPs in the vitreous of patients with retinal detachment and the predictive value of MMPs f or the future development of PVR. METHODS. A prospective study was con ducted on 140 consecutive patients with a rhegmatogenous retinal detac hment in whom vitrectomy was considered necessary because of a giant r etinal tear and the presence of preoperative PVR, among other reasons. Vitreous samples were obtained and analyzed by zymography for the pre sence of MMPs. The patients were then followed up for the development of postoperative PVR (mild and severe). RESULTS. Two species of MMPs w ere detected in the vitreous: MMP-2 and MMP-9. MMP-2 was detected in a ll of the vitreous samples obtained, whereas MMP-9 was found in only 6 4 (47%) of 136 samples. The levels of MMPs detected were not significa ntly associated with the presence of preoperative PVR (P > 0.05), but they were significantly associated (P < 0.05) with the development of postoperative PVR (mild and severe). CONCLUSIONS. The results from thi s prospective study suggest that MMPs may be an important predictor an d may also play a role in the development of postoperative PVR.