An implantable device is described. An implantable transducer (200) converts between electrical energy and acoustic energy. An implantable electronics module (600) is in communication with the transducer and processes electronic data signals associated with the transducer. A fluid filled catheter (202) has a proximal end coupled to the transducer, and a distal end having a distal opening (500) to cerebrospinal fluid in an implanted patient.
