A microactuator has a proximal end configured to receive an electrical signal and a distal end configured to be inserted into a fenestration of an otic bone to provide access through the lateral wall of the cochlea of a subject. The microactuator includes a piezoelectric transducer assembly having a piezoelectric transducer disposed on a membrane (the piezoelectric transducer having a smaller dimension than a corresponding dimension of the membrane), a hermetically sealed fluid cavity filled with a fluid sealed at a first end to a first side of the piezoelectric transducer assembly and at a second end to a diaphragm, a second cavity containing a vacuum or a gas sealed at a first end to a second side of the piezoelectric transducer assembly and at a second end to an end cap.
