A pneumatically operated intraocular surgery apparatus which is of very light weight and small size, the cutting device inserted into the eye consisting of concentric tubes having a diameter of 1 mm. or less. Pneumatic means is provided to the device for moving one of the tubes with respect to the other at a slow or fast rate. Said pneumatic means includes a bellows provided with suction so that vitreous sucked into one of the tubes is sheared off by the sharp end of the other tube and the severed vitreous is sucked into a calibrated cylinder. An adjustable bleeder valve is provided in the vacuum line to eliminate residual suction on the interior of the eye when the cutting action is at rest.