Implantable sensor and system for in vivo measurement and control of fluid constituent levels

An implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another, the source and detector adapted to be fully implanted and set in place to allow plural measurements to be taken at different time periods from a single in vivo position;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the body fluid.

An infusion pump system for monitoring at least one chemical constituent of body fluid in a mammal and delivering medication to the mammal, the system comprising:

• (a) an implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor including:
• (i) a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region;
• (ii) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the plurality of different wavelengths, wherein the source and the detector are adapted to be located so that (1) the light output from the source interacts with a body fluid before being received by the detector, and (2) light from each of the plurality of different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• and
• (iii) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent of the body fluid;
• and
• (b) a pump module connected to the sensor for dispensing doses of medicine in response to the concentration of the chemical constituent output from the processor.

An implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a chamber which has a porosity sufficient to allow interstitial fluid or gel to pass therethrough but which inhibits adjacent tissue and solid material from passing therethrough;
• (b) a source of light disposed within the chamber that emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region;
• (c) a detector disposed within the chamber and spaced from the source for detecting light emitted from the source and outputting a signal which contains spectra of the interstitial fluid or gel at each of the plurality of different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with the interstitial fluid or gel before being received by the detector, and (ii) light from each of the plurality of different wavelengths has a substantially collinear optical path through the interstitial fluid or gel with respect to one another;
• and
• (d) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the interstitial fluid or gel.

A method of determining a concentration of a constituent of body fluid in a mammal using in vivo spectroscopy, the method comprising the steps of:

• (a) implanting a sensor system in the mammal, the sensor system including a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with a body fluid containing the at least one constituent before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another, the sensor system being positioned so that the infrared light also passes through extraneous tissue;
• (b) emitting light from the source;
• (c) obtaining a signal at an output of the detector which contains a composite spectra including spectra of the body fluid at each of the different wavelengths, and spectra of the tissue at each of the different wavelengths, the tissue spectra resulting from the extraneous tissue;
• and
• (d) analyzing the signal to determine the concentration of the constituent of the body fluid, the analysis including correcting for the spectra of the tissue.

A method of determining a concentration of blood glucose in a mammal using in vivo spectroscopy, the method comprising the steps of:

• (a) implanting a sensor system in the mammal, the sensor system being positioned extravascularly, the sensor system including a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with blood in a blood vessel before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the blood vessel with respect to one another;
• (b) emitting light from the source;
• (c) obtaining a signal at an output of the detector which contains spectra of the blood at each of the different wavelengths;
• and
• (d) analyzing the signal to determine the concentration of glucose in the blood.

A method of determining a concentration of blood glucose in a mammal using in vivo spectroscopy, the method comprising the steps of:

• (a) implanting a sensor system in the mammal, the sensor system being positioned around a vascular membrane, the sensor system including a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with blood in the vascular membrane before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the vascular membrane with respect to one another;
• (b) emitting light from the source;
• (c) obtaining a signal at an output of the detector which contains spectra of the blood at each of the different wavelengths;
• and
• (d) analyzing the signal to determine the concentration of glucose in the vascular membrane.

A method of determining a concentration of a constituent of interstitial fluid or gel in a mammal using in vivo spectroscopy, the method comprising the steps of:

• (a) implanting a sensor system in the mammal in a region of the body containing interstitial fluid or gel, the sensor system including a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with the interstitial fluid or gel before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the interstitial fluid or gel with respect to one another;
• (b) emitting light from the source;
• (c) obtaining a signal at an output of the detector which contains spectra of the interstitial fluid or gel at each of the different wavelengths;
• and
• (d) analyzing the signal to determine the concentration of at least one constituent of the interstitial fluid or gel.

A method of determining a concentration of a constituent of body fluid in a mammal using in vivo spectroscopy, the method comprising the steps of:

• (a) implanting a sensor system in the mammal, the sensor system including a source of light which emits at a plurality of different wavelengths in the near-infrared region from about 1,000 nanometers to about 2,500 nanometers, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• (b) emitting light from the source in the near-infrared region from about 1,000 nanometers to about 2,500 nanometers;
• (c) obtaining a signal at an output of the detector which contains spectra of the body fluid at each of the different wavelengths;
• and
• (d) analyzing the signal to determine the concentration of the constituent of the body fluid.

An implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at a plurality of different wavelengths, the source including:
• (i) a plurality of individual source elements, each emitting light at a different wavelength in the infrared region, and
• (ii) a diffraction grating coupler for receiving the light at the emitted wavelengths and outputting the light at the different wavelengths in a substantially collinear optical path with respect to one another, the output of the diffraction grating coupler being the emitted output of the source;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the body fluid.

An implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at plurality of different wavelengths, at least one of the wavelengths being in the infrared region, the source including a broadband light source which simultaneously emits light having a spectra that includes at least the different wavelengths;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the different wavelengths, the detector including:
• (i) a single collection optical fiber for receiving broadband light which has interacted with the body fluid;
• (ii) a fixed grating for receiving the broadband light which has interacted with the body fluid and spectrally separating the received broadband light into a plurality of predefined wavelengths;
• and
• (iii) a plurality of photodetectors, wherein each photodetector detects light at one of the predefined wavelengths,
• wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the body fluid.

An implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at plurality of different wavelengths in the near-infrared region from about 1,000 nanometers to about 2,500 nanometers;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the body fluid.

An implantable sensor adapted for determining a concentration of blood glucose in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at plurality of different wavelengths, at least one of the wavelengths being in the infrared region;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with blood in a blood vessel before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the blood vessel with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of glucose in the blood.

An implantable sensor adapted for determining a concentration of blood glucose in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at plurality of different wavelengths, at least one of the wavelengths being in the infrared region;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the blood at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with blood in a vascular membrane before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the vascular membrane with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of glucose in the blood.

An implantable sensor adapted for determining a concentration of a chemical constituent of interstitial fluid or gel in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at plurality of different wavelengths, at least one of the wavelengths being in the infrared region;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the interstitial fluid or gel at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with the interstitial fluid or gel before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the interstitial fluid or gel with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the interstitial fluid or gel.

A method of determining a concentration of a constituent of body fluid in a mammal using in vivo spectroscopy, the method comprising the steps of:

• (a) implanting a sensor system in the mammal, the sensor system including a source of light which emits at at least three different wavelengths, at least one of the wavelengths being in the infrared region, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• (b) emitting light from the source at at least the three different wavelengths;
• (c) obtaining a signal at an output of the detector which contains spectra of the body fluid at each of the different wavelengths;
• and
• (d) analyzing the signal to determine the concentration of the constituent of the body fluid.

An implantable sensor adapted for determining a concentration of a chemical constituent of body fluid in a mammal using in vivo spectroscopy, the sensor comprising:

• (a) a source of light which emits at at least three different wavelengths, at least one of the wavelengths being in the infrared region;
• (b) a detector for detecting light emitted from the source and outputting a signal which contains spectra of the body fluid at each of the different wavelengths, wherein the source and the detector are adapted to be located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;
• and
• (c) a processor for analyzing the signal and the spectra, and determining therefrom the concentration of the chemical constituent in the body fluid.