Abstract: A console of an ophthalmic surgical system is for operating a surgical handpiece which includes a treatment needle and a drive for driving the treatment needle by oscillation. The console includes a generator configured to provide a time-varying drive signal for the drive, an evaluation unit, and a detection unit. The detection unit is electrically couplable to the drive and detects a contact signal of the drive on account of a second oscillation amplitude in a low-oscillation state of the needle in which the needle oscillates at a maximum first oscillation amplitude. The generator provides the drive signal such that the drive is deactivated during the low-oscillation state. The evaluation unit evaluates the contact signal and determines contact of a particle with the needle on a basis of the evaluation. The detection unit detects the contact signal when the second oscillation amplitude is greater than the first oscillation amplitude.

Abstract: A console of an ophthalmic surgical system is for operating a surgical handpiece which includes a treatment needle and a drive for driving the treatment needle by oscillation. The console includes a generator configured to provide a time-varying drive signal for the drive, an evaluation unit, and a detection unit. The detection unit is electrically couplable to the drive and detects a contact signal of the drive on account of a second oscillation amplitude in a low-oscillation state of the needle in which the needle oscillates at a maximum first oscillation amplitude. The generator provides the drive signal such that the drive is deactivated during the low-oscillation state. The evaluation unit evaluates the contact signal and determines contact of a particle with the needle on a basis of the evaluation. The detection unit detects the contact signal when the second oscillation amplitude is greater than the first oscillation amplitude.

Abstract: An ophthalmic surgical device includes an irrigation line for irrigation fluid flowing from an irrigation container to a handpiece and an aspiration line for aspiration fluid flowing from the handpiece to a collecting container. A first volumetric flow rate determination apparatus is arranged upstream of the handpiece and determines a first volumetric flow rate in the irrigation line. A second volumetric flow rate determination apparatus is arranged downstream of the handpiece and determines a second volumetric flow rate in the aspiration line. An occlusion determination apparatus acquires a time curve of the first volumetric flow rate and a time curve of the second volumetric flow rate, to compare with stored time curves of the first volumetric flow rate for different occlusion states and stored time curves of the second volumetric flow rate for different occlusion states, and to determine a current occlusion state in the aspiration line therefrom.