A tissue removal device includes a cannula that can aspirate tissue under a vacuum applied in the cannula, and a hermetically sealed fluid regulator in fluid communication with the cannula that generates vacuum pulses according to a controllable pulse rate and flow rate. The tissue removal device may also have a vacuum conduit having two or more conduit sections where the inner diameter of an upstream conduit section is smaller than the inner diameter of a succeeding conduit section. A device is also provided for applying an elastic membrane to an open end of the cannula to allow a user to remove any remaining cortical material after cataract material has first been removed from the eye by vacuum pressure applied in the cannula.