RESUMO
OBJECTIVE: To conduct a study comparing 3 triamcinolone acetonide preparations in terms of their particle surface observed with a scanning electron microscope, their particle size distribution, and sedimentation in order to discuss their ability to facilitate visualization during vitreous surgery and the clinical results. METHODS: Kenacort-A®, the newer form of MaQaid, and the older form of MaQaid® were used. A scanning electron microscope and a measuring device were used. Sedimentation was measured based on ultraviolet and visible light absorption spectra. RESULTS: Observation of the particle surface revealed that small particles of the older form of MaQaid® had clumped together, and they contained numerous voids. It had a small mean particle dia (almost the same size as the newer form of MaQaid® and Kenacort-A). Kenacort-A was dispersed while the older form of MaQaid® had numerous clumps and ascending particles, and a large sedimentation volume. Small sedimentation volume and few clumps were noted on the newer form of MaQaid®. CONCLUSION: The newer form of MaQaid® had a particle distribution like that of Kenacort-A®, so it should provide good visibility. Moreover, it is free of preservatives, so it may prove to be a useful aid to visualize the vitreous during vitreous surgery.