An ultrasonic handpiece assembly has a horn, a rear mass attached to a rear end of the horn, a needle attached to a front end of the horn, a stack of piezoelectric elements arranged coaxially about the horn, and an L-T spring arranged coaxially about the horn behind the stack. The horn includes a low gain section in front of the stack and a high gain section in front of the low gain section. The assembly has a first L-T mode, a T mode, a second L-T mode, and an L mode at different resonant frequencies. The low gain horn section includes a circumferential groove located at a vibrational node of the L-T mode. Frequency separation between the first L-T mode and T mode results in torsional vibration of the first L-T mode interacting constructively with torsional vibration of the T mode, thereby increasing torsional stroke in the T mode.

A system and method that includes inserting a needle of a phacoemulsification handpiece into an eye of a patient and vibrating the needle in a first trajectory. Matter from the eye is aspirated via an aspiration line while the needle is vibrated in the first trajectory. An indication is received, of a vacuum level in the aspiration line. Determined is, that the vacuum level has changed by at least a preset vacuum level change, and in response vibrating the needle is switched to a second trajectory, different from the first trajectory.

A surgical instrument includes a transducer assembly with a housing having a conduit section and a base portion. A fluid passageway is defined through the conduit and base portion, an ultrasonic transducer including a plurality of piezoelectric elements and a plurality of electrodes are arranged in a stack configuration, where an electrode is located between each pair of piezoelectric elements. A first borehole is defined through the ultrasonic transducer and an end mass having a second borehole defined therethrough. A surface of the end mass is positioned adjacent a first end of the ultrasonic transducer, the end mass is configured to engage with the housing, and the conduit section of the housing is configured to pass through the second borehole of the end mass. The end mass is configured to compress the ultrasonic transducer against a surface of the housing when the end mass is engaged with the housing.

An eye surgery system includes an Input/Output (I/O) device and a processor. The I/O device is configured to enable a user to define one or more eye surgery protocols, and further configured to, using the I/O device, present a graphical user interface (GUI) that displays one or more user defined eye surgery protocols. The processor is configured to (a) present the one or more user defined eye surgery protocols on the I/O device using the GUI, (b) test compatibility of the one or more user defined eye surgery protocols with the eye surgery system, and (c) provide an indication of the compatibility to a user of the eye surgery system.

A system includes an enclosure, an irrigation retainer, one or more sensors, and a processor. The irrigation retainer is coupled with the enclosure and configured to accept an irrigation container holding irrigation fluid for pumping to a phacoemulsification handpiece. The one or more sensors are coupled with the irrigation retainer and configured to provide at least one signal indicative of a remaining amount of the irrigation fluid. The processor is configured to receive the at least one signal, and in response to the at least one signal, output an estimation of the remaining amount of the irrigation fluid in the irrigation container or an estimation of the amount of irrigation fluid used.

A sonar transducer includes an acoustic radiating piston, a piezoelectric stack, and a non-uniform central fastener. The acoustic radiating piston emits and receives acoustic waves. The piezoelectric stack includes a plurality of piezoelectric elements. The piezoelectric stack converts output electrical signals into mechanical vibrations and converts received mechanical vibrations into input electrical signals. The non-uniform central fastener has a body extending from a first end to a second end to define a fastener length. The non-uniform central fastener extends through the piezoelectric stack and applies a pre-stress to the piezoelectric stack. The non-uniform central fastener has a non-uniform profile along the fastener length.