Optical detection of interrupted fluid flow to ablation probe

A method of detecting an air bubble in a fluid flow, comprising the steps of:

• providing a fluid source for supplying a fluid;
• providing an optical sensor unit including a light-emitting element and a light-receiving element, the optical sensor unit operably associated with a first fluid path, the first fluid path leading from the fluid source to an electrosurgical device;
• performing a first calibration step by directing light from the light-emitting element through air flow in the first fluid path passing through the optical sensor unit and sensing a characteristic of light collected at the light-receiving element to determine a first reference value;
• performing a second calibration step by directing light from the light-emitting element through fluid flow in the first fluid path passing through the optical sensor unit and sensing a characteristic of light collected at the light-receiving element to determine a second reference value;
• operating the optical sensor unit to direct light from the light-emitting element through the first fluid path passing through the optical sensor unit and to sense a characteristic of light collected at the light-receiving element to determine a third reference value;
• when an air bubble in the fluid flow is detected by the optical sensor unit, outputting an electrical signal from the optical sensor unit to a flow diverter apparatus and an electrosurgical energy source in response to detection of the air bubble in the fluid flow;
• and
• adjusting energy output of the electrosurgical energy source in response to the electrical signal from the optical sensor unit.

A method of detecting an air bubble in a fluid flow, comprising:

• monitoring fluid flow in a fluid path to detect an air bubble in the fluid flow at an optical sensor operably associated with the fluid path, the optical sensor including a light-emitting element and a light-receiving element;
• outputting an electrical signal from the optical sensor to a flow diverter apparatus in response to a detection of an air bubble in the fluid flow;
• diverting the fluid flow at the flow diverter to a container in response to the electrical signal from the optical sensor;
• and
• adjusting energy output of an electrosurgical energy source in response to the electrical signal from the optical sensor.