#$%^&*AU2013213672A120130822.pdf#####Abstract A control system for operating a vitrectomy probe and controlling a port size of the vitrectomy probe comprising: a first isolation valve a first output port coupled to the first isolation valve, the first output port operable to communicate pneumatic pressure from the first isolation valve to the vitrectomy probe a second isolation valve a second output port coupled to the second isolation valve, the second output port operable to communicate pneumatic pressure from the second isolation valve to the vitrectomy probe a controller operable to: oscillate the first isolation valve between a first position in which pneumatic pressure from the first output port is vented to the atmosphere and a second position in which pneumatic pressure is conducted to the first output port and oscillate the second isolation valve between a first position in which pneumatic pressure from the second output port is vented to the atmosphere and a second position in which pneumatic pressure is conducted to the second output port, movement of the first isolation valve from the first position to the second position synchronized with movement of the second isolation valve from the second position to the first position to define the port size of the vitrectomy probe.
