Abstract: Apparatus and methods for shifting an image back and forth between first and second portions of the retina are described. Apparatus constructed in accordance with principles of the present invention preferably include spectacles, a fixed mirror, a pivoting mirror, a drive motor coupled to the pivoting mirror, and control circuitry coupled to the drive motor, the control circuitry causing the drive motor to pivot between first and second positions to shift an image from a first to a second portion of the retina.

Abstract: An infusion cannula for use in clearing and preventing condensation on the posterior surface of an artificial lens during the fluid-gas exchange portion of a pars plana vitrectomy is described. The infusion cannula directs the flow of gas entering the eye toward the posterior surface of the lens. The moisture content of the gas supplied to the infusion cannula is minimized in order to increase the effectiveness with which condensation is removed or prevented. Additionally, the temperature of the gas supplied to the infusion cannula is controlled to further increase the effectiveness with which condensation is removed.