Detection of fluids in tissue

A method of detecting extravasation of a fluid injected into a vascular structure of a body in tissue outside of the vascular structure, comprising the steps of:

• applying electromagnetic energy in the frequency range of approximately 300 MHz to approximately 30 GHz to a first volume of the body during a period of time in which a fluid is injected into the vascular structure;
• measuring a resultant signal;
• and
• comparing the signal to a reference signal to determine fluid level in the tissue has changed during the period of time.

A method of detecting extravasation of a fluid injected into a vascular structure of a body in tissue outside of the vascular structure, comprising the steps of:

• placing at least one antenna in operative connection with the skin of the body;
• applying electromagnetic energy in the frequency range of aporoximately 300 MHz to approximately 30 GHz to a first volume of the body using the antenna;
• injecting the fluid into the vascular structure;
• measuring a returned signal;
• and
• comparing the signal to a reference signal to determine if extravasation has occurred.

A method of detecting a change in the level of fluid in tissue in a body comprising the steps of:

• transmitting electromagnetic energy in the frequency range of approximately 300 MHz to approximately 30 GHz in the vicinity of a surface of the body such that changes in the surface geometry of the surface resulting from a change in fluid level of underlying tissue affect a resultant signal;
• measuring the resultant signal;
• and
• comparing the resultant signal to a reference signal.

An injection system comprising:

• an injector to inject a fluid into a vascular structure in a body;
• at least a first transmitter including an antenna adapted to transmit electromagnetic energy in the frequency range of approximately 300 MHz to approximately 30 GHz to a first volume of the body;
• at least a first receiver to measure a returned signal;
• a memory storing a reference signal, the reference signal created by transmitting electromagnetic energy into the first volume of the body prior to an injection and measuring a resultant signal;
• and
• a signal processor in communication with the first receiver and the memory, the processor comparing the returned signal to the reference signal to determine if the level of fluid in tissue outside the vascular structure has changed.

A system for injection of an injection fluid into a body comprising:

• a pressurizing chamber in which injection fluid is pressurized for injection into a vascular structure of a body;
• and an extravasation detector, the extravasation detector including at least a first transmitter including an antenna adapted to transmit electromagnetic energy in the frequency range of approximately 300 MHz to approximately 30 GHz to a first volume of the body;
• at least a first receiver to measure a returned signal;
• a memory storing a reference signal, the reference signal created by transmitting electromagnetic energy into the first volume of the body prior to an injection of fluid and measuring a resultant signal;
• and a signal processor in communication with the first receiver and the memory, the processor comparing the returned signal to the reference signal to determine if the level of fluid in tissue outside the vascular structure has changed.

A method of detecting a change in the level of fluid in tissue of a body comprising the steps of:

• applying electromagnetic energy in the frequency range of greater than 1.5 GHz to approximately 30 GHz to a first volume of the body using at least one antenna;
• measuring a resultant signal using at least one other antenna;
• and
• comparing the signal to a reference signal.