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During a central vitrectomy I want to remove the central vitreous without hypotonia, to avoid incarceration and to induce retinal tears at the vitreous base level, and I want to do it efficiently. I can easily avoid any hypotonia in choosing my maximum aspiration flow always lower than my maximum infusion flow; so the first thing to do when receiving a new machine is to calculate both maximum infusion flow and aspiration flow. To reduce the risk of incarceration, I never use the PIO system and I systematically stop the infusion before removing any instrument from the sclerotomy even when the trocar is equipped with a valve. The risk of inducing a retinal tear at the vitreous base level is the main issue. We face a crucial dilemma: the higher the aspiration flow the more efficient the procedure but the more traction is exerted; the faster the cutting frequency the less efficient the procedure but the less traction is exerted. The problem is that the required parameters change constantly during the procedure, highlighting the necessity of working with a bilinear foot pedal controlling simultaneously and independently the aspiration flow and the cutting frequency. For central vitrectomy a medium of 12 cc/mm aspiration flow and 800 cuts/min are my usual parameters. I will demonstrate how high speed cutting (i.e. 6,000 to 8,000 cuts/min) facilitate the aspiration of the sole BSS located around the port of the hand piece. For peripheral vitrectomy, when the question is to remove the adherent vitreous attached to the retina, we should select an aspiration flow exerting a force near the total of forces maintaining the retina; most of the time, we are speaking of flow between 1 to 3 cc/min. Having a precise control of the aspiration flow, I am not forced to work with high speed cutting, as I should if I was using a machine with a venturi pump. At that particular moment the pressure at pump level is positive (the pump reducing the natural outflow induced by the infusion pressure) explaining why one cannot work like that with a venturi pump (which can only induce a depression). I can therefore cut very slowly, selecting precisely the vitreous fibers close to the retina and cutting them cut after cut.