An ophthalmic surgical hand piece comprises a driver coupled to a horn, a venturi pump with an inlet aspiration port and an outlet aspiration port, and a hand piece shell at least partially enclosing the driver, the horn, and the venturi pump. A needle is coupled to an end of the horn. A rigid, non-compliant aspiration path extends between the hollow needle and the outlet aspiration port. An aspiration pressure sensor measures a pressure in the aspiration path.
