Q-factor control for use with retained surgical item detection system

An interrogation and detection system for detection of surgical implements within a body of a patient, the interrogation and detection system comprising:

• an RF tag configured to transmit a return signal when energized;
• a signal generator configured to generate an energizing signal for the RF tag;
• an antenna operably coupled to the signal generator, the antenna configured to receive the return signal transmitted by the RF tag;
• a processor;
• and
• a memory, including instructions stored thereon, which when executed by the processor, cause the system to:
• measure a current through the antenna;
• determine an electrical damping factor (Q factor) of the antenna based on the measured current;
• and
• compare the determined Q factor to a predetermined value.

A computer-implemented method for detection of surgical implements within a body of a patient, the method comprising:

• generating, by a signal generator, an energizing signal for an RF tag, the RF tag affixed to a surgical implement;
• receiving a return signal from the RF tag by an antenna operably coupled to the signal generator;
• measuring a current through the antenna;
• determining a Q factor of the antenna based on the measured current;
• comparing the determined Q factor to a predetermined value;
• and
• adjusting the Q factor of the antenna based on the comparison.