Methods and apparatus for monitoring and quantifying the movement of fluid

DETAILED DESCRIPTION OF THE INVENTION While the present invention may be embodied in many different forms, disclosed herein are specific illustrative embodiments thereof that exemplify the principles of the invention.
It should be emphasized that the present invention is not limited to the specific embodiments illustrated.
Those skilled in the art will appreciate that while the present invention is particularly suited for the determination of blood flow rates and the rate of tissue perfusion it is equally applicable to the determination of the flow rates of other fluids as well.
For example, it may be used to measure the movement of fluid in the lymph system or the movement of fluid in the spinal column.
Further, the present invention is entirely compatible for monitoring and measuring the movement of fluid in non-biological systems such as pipes or hydraulic systems.
In any event, when using the invention in a biological system a contrast or imaging agent is introduced into fluids passing through or permeating the target region or tissue.
The imaging agent is subsequently transported into the target region or tissue.
As described previously, the imaging agent present within the target region or tissue is disrupted to the extent that its ability to produce a detectable signal upon subsequent interrogation is, at least partially, impaired.
The localized disruption does not substantially impact the ability of the imaging agent outside the target region to produce a detectable signal.
Nondisrupted or intact contrast agent is transported into the target region with the flowing or circulating fluid and, as it is detected, allows for the determination of flow rate of the fluid and perfusion rate through the target region.
In preferred embodiments, the present invention can be used to directly calculate the rate of blood flow in a selected vein or artery, or calculate the rate of perfusion in a volume of tissue permeated by a microvascular lattice.
It will further be appreciated that the method may be performed with a wide variety of contrast agents using a number of detection procedures