Abstract
Abstract: :
Purpose: To detect differences in quantity and types of cells found in vitreous samples from patients with rhegmatogenous retinal detachment (RD) without PVR versus those with PVR. Also, to determine variations in vitreous cytology from patients with PVR with different time of evolution. Methods: Diluted vitreous specimens were collected from 133 patients during a pars plana vitrectomy for RD (n=49) and PVR (n=84). PVR samples were divided in different groups according to the evolution time (range: 1 week to 6 months). Specimens were centrifuged and then processed through two different procedures: direct paraffin embedding and cytospin. Different cell types, according to their morphological features, were identified. For statistical purposes a scale of cellular density was established for each cellular type: 0=no presence; 1=low density; and 2=high density. Student t test was done to establish differences in the cellularity of two groups. In order to find variations in the density of each cellular type in the PVR group with different time of evolution a quadratic model was performed. Results: There were not statistically significant differences between vitreous samples from patients with PVR and patients with RD without PVR neither in the amount nor in the type of cells. In PVR, density of macrophages decreased along the study in a lineal pattern. Furthermore, epithelial-like cells increased their levels until 4th month and then decreased while pigment loaded cells decreased until the 4th month and then increased. Conclusion: There were differences in vitreous cells density along the time, mainly in macrophages, pigment loaded cells and epithelial-like cells in PVR samples. Cytological analysis of vitreous samples at different time of evolution of PVR can provide data about chronobiology of the disease. This information can be useful to increase knowledge on the pathobiology of the disease.
Keywords: 524 proliferative vitreoretinopathy • 563 retinal detachment • 381 cytology