Wearable device with multimodal diagnostics

Inventors

Honore, Francis • Reich, James • Flannery, JR., Anthony F. • Gupta, Samit Kumar • Abhishek, Ramkumar

Assignees

Alio Inc

Abstract

Systems and methods to non-invasively measure sub-cutaneous processes in a patient are disclosed. Examples of systems may optically detect biological fluid properties. The optical detection techniques described herein may be incorporated into a wearable monitoring system. Examples of wearable monitoring systems may simultaneously measure a plurality of sensory modalities. Systems of the present disclosure may be mounted on the skin of a patient.

Core Innovation

A method for determining physiological properties of a patient emits a first illumination of a volume of tissue below a skin surface from a first light source located at a first distance from a photodetector positioned on the skin surface. The first light source emits the first illumination at a plurality of first output intensities, and each first output intensity corresponds to a first radius of a hemispherical region of influence. A first set of electrical signals is received representing reflection intensities communicated from the photodetector receiving light reflected below the skin surface from the first illumination.

The method emits a second illumination from a second light source located at a second distance from the photodetector, where the second light source emits the second illumination at a plurality of second output intensities, and each second output intensity corresponds to a second radius of a hemispherical region of influence. A second set of electrical signals is received representing reflection intensities communicated from the photodetector receiving light reflected below the skin surface from the second illumination. The first and second sets of electrical signals are used to measure a depth of a blood vessel within the volume of tissue below the skin surface.

Further methods use corresponding reflection intensities and hemispherical-region radii to measure a diameter of a blood vessel, and in some cases to measure both depth and diameter of the blood vessel within the volume of tissue below the skin surface. Additional dependent aspects include using wavelength-dependent reflection intensity radii to determine the vessel properties, calculating a ratio of reflection intensities for first and second wavelengths, and identifying signal artifacts across a period to determine heart rate. Radii-based analysis also supports identifying a primary light source based on which intersection is larger.

Claims Coverage

The partial content includes three independent method claims. Across these claims, the coverage centers on using two illuminations at different source distances with multiple output intensities mapped to radii of hemispherical regions of influence, and using the corresponding photodetector reflection-intensity signals to measure vessel geometry within tissue below a skin surface. Dependent claims further refine the inventive features with wavelength-based processing, ratio-based oxygenation-level storage, artifact-based heart-rate determination, and intersection-based selection of a primary light source.

Across the independent claims, the core claim coverage is a two-illumination approach that uses a photodetector on the skin surface, multiple illumination intensities mapped to radii of hemispherical regions of influence for each illumination distance, and the resulting reflection-intensity signal sets to measure blood vessel depth and/or diameter. Dependent claim features in the partial content include wavelength-based processing, oxygenation-level ratio calculations, artifact-period analysis for heart rate determination, and intersection-based selection of a primary light source.

Stated Advantages

Documented Applications