[Comparison of different techniques for cytologic analysis of vitreous specimens].

Purpose: To assess the efficacy of four methods to study the cytology of vitreous samples, and to evaluate the most efficient for routine analysis and immunocytochemical staining.
Methods: Diluted and undiluted vitreous samples of 87 consecutive patients suffering vitreoretinal surgery for different diseases were analysed. The specimens were centrifugated and then processed through four different procedures: agar sandwich (29 cases), direct paraffin embedding (33 cases), cytospin preparations (82 cases) and cytoblock (8 cases).
Results: Evaluable material was obtained in: agar sandwich 18 out of 29 cases (62%), direct paraffin embedding 32 out of 33 cases (96.9%), cytospin 72 out of 82 cases (87.8%) and cytoblock 1 out of 8 cases (12.5%).
Conclusions: Direct paraffin embedding and cytospin are the most efficient procedures for routine purposes. Agar sandwich technique seems to be useful for studying small pieces of tissue. Direct paraffin embedding and agar sandwich technique seems to be valuable for immunocytochemistry. After 8 cases processed with cytoblock, our experience did not show valuable results for processing vitreous samples.