Systems, methods, and apparatus for pressure-wave ocular therapy

An apparatus for treating an eye, the apparatus comprising:

• a housing comprising a fluid-filled chamber and an eye-contacting surface configured to contact a surface of an eye;
• a first electrode disposed within the housing;
• and
• a second electrode disposed within the housing and coaxially aligned with the first electrode, wherein a distal tip of the first electrode and a distal tip of the second electrode are separated by a gap,
• wherein the first electrode and the second electrode are configured to generate an electric arc across the gap when energized and produce a shockwave in a fluid of the fluid-filled chamber,
• further comprising a fluid inlet and a fluid outlet in fluid communication with the fluid-filled chamber, wherein the apparatus further comprises a conductivity sensor at least partially disposed within the fluid-filled chamber and configured to measure a conductivity periodically or continuously of the fluid within the fluid-filled chamber wherein the conductivity sensor is configured to monitor changes in conductivity caused by release of metallic ions from the first and second electrodes during erosion of the electrodes.