Abstract
PURPOSE: This study analyzes the efficiency of different vitrectomy systems and compares single with double-bladed cutters. METHODS: The systems EVA™ (DORC), Constellation(®) Vision System (ALCON), megaTRON S4(HPS) (Geuder) and Stellaris(®) PC (Bausch and Lomb) were used. We chose 20G and 23G probes, since not all systems had switched to a smaller G at the time the study was conducted in 2016. Cut rates were varied in increments of 1000 cuts/min from 500 cpm to the system's maximum and vacuum pressures were varied in increments of 100 mmHg, from 100 to 600 mmHg up to the individual system's maximum. In this study water, egg white, Pluronic(®-)F127 gel and isolated porcine vitreous were used as models of human vitreous. The vitrectomy efficiency was calculated from the aspirated mass (g) within 30 s. The aperture of the different vitrectomy probes was filmed with a high-speed camera. RESULTS: The area under the curve analysis showed differences in efficiency between vitrectomy systems. For water, a reverse relationship between the aspirated mass and cut rate was shown. By contrast, for most systems aspirated egg white and porcine vitreous showed a non-linear increase or decrease for 4000 cpm and above. For all vitreous surrogates, EVA™'s double-bladed probe aspirated significantly (p < 0.001) more vitreous than its mono-bladed probe. Video recordings showed less vitreous traction for double- in contrast to single-bladed probes. CONCLUSION: We can demonstrate differences in the efficiency of vitrectomy depending on the vitrectomy system used. Double-bladed probes were more efficient and probably safer than single-bladed probes.