Phototherapeutic light for treatment of pathogens
Methods and related devices for impinging light on tissue, for example within a body of a patient, to induce various biological effects are disclosed. Biological effects may include at least one of inactivating and/or inhibiting growth of one or more pathogens, upregulating a local immune response, stimulating enzymatic generation of nitric oxide to increase endogenous stores of nitric oxide, releasing nitric oxide from endogenous stores of nitric oxide, and inducing an anti-inflammatory effect. Wavelengths of light are selected based on intended biological effects for one or more of targeted tissue types and targeted pathogens. Light treatments may provide multiple pathogenic biological effects, either with light of a single wavelength or with light having multiple wavelengths. Devices and methods for light treatments are disclosed that provide light doses for inducing biological effects on various targeted pathogens and targeted tissues with increased efficacy and reduced cytotoxicity.
1 . A method comprising:
providing light comprising a first peak wavelength and a second peak wavelength, the light generated by an illumination device with at least one light source, driver circuitry configured to drive the at least one light source, a heat sink in thermal communication with the at least one light source, a thermal sensor in communication with the driver circuitry, wherein the driver circuitry is configured to electrically deactivate the at least one light source in response to the thermal sensor if a predetermined operating temperature range is exceeded, and an optic configured to preferentially direct the light in a non-perpendicular direction from a mounting plane of the at least one light source, the optic forming part of a protective covering that encases the at least one light source, the heat sink, and the driver circuitry with light-transmissive material; and
irradiating mammalian tissue with the light;
wherein the first peak wavelength differs from the second peak wavelength by at least 5 nanometers (nm) and the first peak wavelength and the second peak wavelength are in a range from 400 nm to 900 nm.
2 . The method of claim 1 , wherein:
the first peak wavelength is configured to induce a first biological effect, and the second peak wavelength is configured to induce a second biological effect that is different than the first biological effect; and
the first biological effect and the second biological effect comprise different ones of inactivating one or more pathogens that are in a cell-free environment, inhibiting replication of the one or more pathogens that are in a cell-associated environment, upregulating a local immune response, stimulating enzymatic generation of nitric oxide to increase endogenous stores of nitric oxide, releasing nitric oxide from endogenous stores of nitric oxide, and inducing an anti-inflammatory effect.
3 . The method of claim 2 , wherein the first biological effect comprises inactivating the one or more pathogens that are in a cell-free environment and inhibiting replication of the one or more pathogens that are in a cell-associated environment.
4 . The method of claim 3 , wherein the first biological effect further comprises upregulating a local immune response.
5 . The method of claim 1 , wherein the first peak wavelength is in a range from 400 nm to 490 nm and the second peak wavelength is in a range from 490 nm to 900 nm.
6 . The method of claim 1 , wherein the first peak wavelength is in a range of from 410 nm to 440 nm.
7 . The method of claim 2 , wherein the light further comprises a third peak wavelength that is configured to induce a third biological effect that is different than the first biological effect and the second biological effect, wherein:
the first peak wavelength is in a range from 400 nm to 490 nm;
the second peak wavelength is in a range from 490 nm to 900 nm; and
the third peak wavelength is in a range from 200 nm to 400 nm.
8 . The method of claim 1 , wherein irradiating the mammalian tissue with the light comprises administering the first peak wavelength in a first time window and the second peak wavelength in a second time window.
9 . The method of claim 8 , wherein the first time window is the same as the second time window.
10 . The method of claim 8 , wherein the first time window is different than the second time window.
11 . The method of claim 10 , wherein the first time window overlaps with the second time window.
12 . The method of claim 10 , wherein the first time window is non-overlapping with the second time window.
13 . An illumination device comprising:
at least one light source arranged to impinge light on mammalian tissue within a body, the light comprising at least a first peak wavelength and a second peak wavelength and the first peak wavelength differs from the second wavelength by at least 5 nanometers (nm), wherein the first peak wavelength and the second peak wavelength are in a range from 400 nm to 900 nm;
driver circuitry configured to drive the at least one light source;
a heat sink in thermal communication with the at least one light source;
a thermal sensor in communication with the driver circuitry, the driver circuitry configured to electrically deactivate the at least one light source in response to the thermal sensor if a predetermined operating temperature range is exceeded; and
an optic configured to preferentially direct the light in a non-perpendicular direction from a mounting plane of the at least one light source, the optic forming part of a protective covering that encases the at least one light source, the heat sink, and the driver circuitry with light-transmissive material.
14 . The illumination device of claim 13 , wherein:
the first peak wavelength is configured to induce a first biological effect, and the second peak wavelength is configured to induce a second biological effect that is different than the first biological effect; and
the first biological effect and the second biological effect comprise different ones of inactivating one or more pathogens that are in a cell-free environment, inhibiting replication of the one or more pathogens that are in a cell-associated environment, upregulating a local immune response, stimulating enzymatic generation of nitric oxide to increase endogenous stores of nitric oxide, releasing nitric oxide from endogenous stores of nitric oxide, and inducing an anti-inflammatory effect.
15 . The illumination device of claim 14 , wherein the first biological effect comprises inactivating the one or more pathogens that are in a cell-free environment in the body and inhibiting replication of the one or more pathogens that are in a cell-associated environment in the body.
16 . The illumination device of claim 15 , wherein the first biological effect further comprises upregulating a local immune response within the body.
17 . The illumination device of claim 13 , wherein the first peak wavelength is in a range from 400 nm to 490 nm and the second peak wavelength is in a range from 490 nm to 900 nm.
18 . The illumination device of claim 13 , wherein the first peak wavelength is in a range from 410 nm to 440 nm.
19 . The illumination device of claim 14 , wherein the light further comprises a third peak wavelength that is configured to induce a third biological effect that is different than the first biological effect and the second biological effect, wherein:
the first peak wavelength is in a range from 400 nm to 490 nm;
the second peak wavelength is in a range from 490 nm to 900 nm; and
the third peak wavelength is in a range from 200 nm to 400 nm.
20 . The illumination device of claim 13 , wherein the at least one light source comprises at least one first emitter that is configured to provide the first peak wavelength and at least one second emitter that is configured to provide the second peak wavelength.
21 . The illumination device of claim 20 , wherein each of the at least one first emitter and the at least one second emitter comprises at least one light emitting diode.
22 . The illumination device of claim 20 , wherein the at least one first emitter comprises a monochromatic light emitting diode and the at least one second emitter comprises a phosphor-converted light emitting diode.
23 . The illumination device of claim 13 , wherein the thermal sensor is within the protective covering.