Apparatus and Method for Mitigating Noise Affecting a Transcutaneous Signal
A system and method include a sensor overlying a target area of skin to aid in diagnosing subcutaneous fluid leakage. The sensor includes an absorbent that minimizes noise in detected electromagnetic radiation to make it easier to analyze a signal that is indicative of subcutaneous fluid leakage.
1 . A method of aiding in diagnosing at least one of infiltration and extravasation, the method comprising:
emitting a first near-infrared signal through an epidermis;
detecting a second near-infrared signal through the epidermis, the second near-infrared signal being a portion of the first near-infrared signal that is at least one of reflected, scattered and redirected by perivascular tissue underlying the epidermis; and
absorbing a third near-infrared signal, the third near-infrared signal being a portion of the first near-infrared signal that is at least one of reflected, scattered and redirected by the epidermis.
2 . The method of claim 1 wherein signal peaks of the first, second and third near-infrared signals are centered about a common wavelength.
3 . The method of claim 2 wherein the common wavelength of the signal peaks of the first, second and third near-infrared signals is centered between approximately 600 nanometers and approximately 2,100 nanometers.
4 . The method of claim 2 wherein the common wavelength of the signal peaks of the first, second and third near-infrared signals is centered between approximately 600 nanometers and approximately 1,800 nanometers.
5 . The method of claim 2 wherein the common wavelength of the signal peaks of the first, second and third near-infrared signals is centered between approximately 800 nanometers and approximately 1,050 nanometers.
6 . The method of claim 1 wherein absorbing the third near-infrared signal comprises absorbing the third near-infrared signal at a first portion of a superficies overlying the target area.
7 . The method of claim 6 wherein emitting the first near-infrared signal comprises emitting the first near-infrared signal at a second portion of the superficies, the first portion of the superficies cincturing the second portion of the superficies.
8 . The method of claim 6 wherein detecting the second near-infrared signal comprises detecting the second near-infrared signal at a third portion of the superficies, the first portion of the superficies cincturing the third portion of the superficies.
9 . The method of claim 6 wherein absorbing the third near-infrared signal comprises absorbing at least approximately 50% of the third near-infrared signal that impinges on the first portion of the superficies.
10 . The method of claim 6 wherein absorbing the third near-infrared signal comprises absorbing at least approximately 90% of the third near-infrared signal that impinges on the first portion of the superficies.
11 . The method of claim 6 , comprising absorbing a fourth near-infrared signal, the fourth near-infrared signal being a portion of the first near-infrared signal that is reflected, scattered and redirected by the perivascular tissue.
12 . The method of claim 11 wherein absorbing the fourth near-infrared signal comprises absorbing at least approximately 50% of the fourth near-infrared signal that impinges on the first portion of the superficies.
13 . The method of claim 11 wherein absorbing the fourth near-infrared signal comprises absorbing at least approximately 90% of the fourth near-infrared signal that impinges on the first portion of the superficies.
14 . The method of claim 1 wherein emitting the first near-infrared signal comprises a first end face of a first optical fiber emitting the emitting the first near-infrared signal.
15 . The method of claim 1 wherein detecting the second near-infrared signal comprises a second end face of a second optical fiber detecting the emitting the second near-infrared signal.
16 . The method of claim 1 , comprising aiding in diagnosing at least one of infiltration and extravasation by detecting the second near-infrared signal.
17 . The method of claim 1 , comprising improving a signal-to-noise ratio of the second near-infrared signal by absorbing the third near-infrared signal.