System and method for tissue analysis using remote PPG
AssigneeKoninklijke Philips N.V.
InventorsMarco Lai, Bernardus Hendrikus Wilhelmus Hendriks
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Abstract
A tissue analysis system and method process images to derive a remote PPG perfusion map from PPG amplitude levels obtained from the images as well as a PPG delay map from PPG relative delays between the PPG signals for each image region (pixel) with respect to a reference signal. The images are segmented into one or more tissue regions based on the PPG delay map (or segmentation information identifying tissue regions derived from the PPG delay map are received as input). The different tissue regions have distinct PPG delay characteristics. A level of perfusion can then be determined separately for each tissue region. Thus PPG delay information is used to enable different tissue types to be identified.
Claims14
A system for tissue analysis, comprising:
- an image sensor configured to capture images of tissue;
- and
- a processor adapted to receive images captured by the image sensor and to process the images to:
- derive a photoplethysmography (PPG) perfusion map from PPG amplitude levels obtained from the images;
- derive a PPG delay map from PPG relative delays between different image regions, wherein the relative delays comprise a delay relative to a reference PPG signal which is an average delay time period for all image regions for a frame of image data;
- segment the images into one or more tissue regions based on the PPG delay map or receive segmentation information identifying tissue regions derived from the PPG delay map, wherein the different tissue regions have distinct PPG delay characteristics;
- and
- determine a level of perfusion separately for each tissue region.
A computer-implemented tissue analysis method, comprising:
- receiving image sensor images;
- deriving a photoplethysmography (PPG) perfusion map from PPG amplitude levels obtained from the images;
- deriving a PPG delay map from PPG relative delays between PPG signals of each image region with respect to a reference signal, wherein the relative delays comprise a delay relative to a reference PPG signal which is an average delay time period for all image regions for a frame of image data;
- segmenting the images into one or more tissue regions based on the PPG delay map or receiving segmentation information identifying tissue regions derived from the PPG delay map, wherein the different tissue regions have distinct PPG delay characteristics;
- and
- determining a level of perfusion separately for each tissue region.
A non-transitory computer-readable storage medium having stored a computer program comprising instructions to perform a method comprising:
- receiving image sensor images;
- deriving a photoplethysmography (PPG) perfusion map from PPG amplitude levels obtained from the images;
- deriving a PPG delay map from PPG relative delays between PPG signals of each image region with respect to a reference signal, wherein the relative delays comprise a delay relative to a reference PPG signal which is an average delay time period for all image regions for a frame of image data;
- segmenting the images into one or more tissue regions based on the PPG delay map or receiving segmentation information identifying tissue regions derived from the PPG delay map, wherein the different tissue regions have distinct PPG delay characteristics;
- and
- determining a level of perfusion separately for each tissue region.
A processor configured to:
- derive a photoplethysmography (PPG) perfusion map from PPG amplitude levels obtained from the images;
- derive a PPG delay map from PPG relative delays between different image regions, wherein the relative delays comprise a delay relative to a reference PPG signal which is an average delay time period for all image regions for a frame of image data;
- segment the images into one or more tissue regions based on the PPG delay map or receive segmentation information identifying tissue regions derived from the PPG delay map, wherein the different tissue regions have distinct PPG delay characteristics;
- and
- determine a level of perfusion separately for each tissue region.
Dependencies are inferred from the claim text.