Vitrectomy surgical apparatus with cut timing based on pressures encountered

A method for performing a vitrectomy procedure, comprising:

• sensing pressure provided from a pressure source through a cut valve and to a vitrectomy handpiece;
• and
• controlling operation of the cut valve based on pressure sensed;
• wherein controlling operation of the cut valve based on pressure sensed comprises monitoring and maintaining a peak pressure value and a trough pressure value and altering cut valve timing based on pressure conditions previously encountered;
• wherein the peak pressure value represents a maximum pressure encountered and the trough pressure value represents a minimum pressure encountered.