System and method for optical detection of skin disease

Abstract

An optical system for the detection of skin disease, such as melanoma, acquires images of a lesion on a subject's skin at different wavelengths and utilizes a sweeping arm rotating about the lesion in a clock-like sweep to produce diagnostically relevant metrics and classifiers from the image data so as to enhance detection of the skin disease.

What is claimed is: 
     
         1 . An apparatus for detecting skin disease in a lesion on a subject's skin, comprising:
 a mechanical fixture defining a distal plane against which a lesion on the subject's skin is pressed;   a camera adapted to obtain image data from the lesion;   a processor adapted to process the image data with a clock-like sweep algorithm to obtain metrics and/or classifiers defining the rotational symmetry of the pigmented lesion; and   an output device that indicates a likelihood of the presence or absence of skin disease in the subject from the processed image data.   
     
     
         2 . The apparatus according to  claim 1 , further comprising one or more lenses mounted in the mechanical fixture between the camera and the distal plane to focus the camera on the distal plane. 
     
     
         3 . The apparatus according to  claim 1 , further comprising an illumination system attached to the mechanical fixture comprising a set of devices that emit light of different spectral profiles in a wavelength range of 300 nm to 950 nm. 
     
     
         1 . apparatus according to  claim 1 , wherein said illumination system includes at least one LED that emits light in a wavelength range of 300 nm to 400 nm. 
     
     
         5 . The apparatus according to  claim 2 , wherein the camera has an optical axis and said illumination system comprises a plurality of LEDs arranged in a ring around the optical axis. 
     
     
         6 . The apparatus according to  claim 1 , further comprising a server application that facilitates the image acquisition process that can be operated independently or controlled through a separate software system capable of file input and output and simulating keystrokes. 
     
     
         7 . The apparatus according to  claim 1 , further comprising a second processor, adapted to receive image data from the first processor, transform the image data into enhanced image data, and transmit the enhanced image data to the first processor, or directly to a display device or a storage device. 
     
     
         8 . The apparatus according to  claim 1 , further comprising a display adapted to display a topographical map of the lesion from mask images formed at each color channel. 
     
     
         9 . The apparatus according to  claim 1 , wherein the processor and the camera are integrated on a cellular phone and the mechanical fixture is adapted to attach to the cellular phone. 
     
     
         10 . apparatus according to  claim 1 , wherein the processor is adapted to transform the image data into diagnostically relevant metrics and/or classifiers defining the rotational distribution of [a] the spatial texture features or [b] the brightness features or [c] the features of the lesion edge/border, including the sharpness with which the lesion borders normal skin or [d] the color variation of a lesion on the subject's skin or [e] variations in the features of the pigmented network including the length, shape, brightness and organization of the lesion segments or [f] the oxygen saturation of the tissue as defined by the amount and ratio of oxyhemoglobin and deoxyhemoglobin. 
     
     
         11 . The apparatus according to  claim 1 , wherein the processor is adapted to sequentially acquire M images, store each pixel in the image as a set of M numbers that form a spectral measurement, and fit the spectral measurement as the weighted sum of N chromophores. 
     
     
         12 . The apparatus according to  claim 11 , further comprising a display adapted to display one or more regions of interest in the lesion in solid false color and to toggle between a red green blue color image of the lesion rendered from three or more of the M images and the same image with one or more regions of interest displayed. 
     
     
         13 . The apparatus according to  claim 12 , wherein the region of interest is selected from the group consisting blood vessels within the lesion border; blue and/or blue white structures in the lesion; regular or irregular pigmented networks; negatively pigmented networks; patterns of oxygen saturation; and patterns of eumelanin and pheomelanin, 
     
     
         14 . A system for detecting skin disease, comprising:
 a cellular phone having an integrated processor and camera, wherein   the camera is provided with an external illumination system or provided with an integral flash adapted to obtain image data from a subject's skin, and   the processor is adapted to process the image data with a clock-like sweep algorithm to obtain metrics and/or classifiers defining the rotational symmetry of the pigmented lesion to produce a display depicting regions of interest in the subject's skin and/or an indication of a likelihood of the presence or absence of skin disease in the subject.   
     
     
         15 . The system according to  claim 14 , further comprising a mechanical fixture mounting against the subject's skin and securing the camera in a fixed position, wherein the fixture defines a distal plane against which a lesion on the subject's skin is pressed. 
     
     
         16 . The system according to  claim 14 , further comprising one or more lenses mounted in said mechanical fixture between the camera and the distal plane to focus the camera on the distal plane. 
     
     
         17 . The system according to  claim 14 , further comprising an illumination system external to the camera attached to the mechanical fixture. 
     
     
         18 . The system according to  claim 14 , wherein the illumination system comprises a set of M light emitting diodes that emit light having different spectral profiles. 
     
     
         19 . The system according to  claim 17 , wherein the external illumination system disables any built in illumination system integral to the camera. 
     
     
         20 . The system according to  claim 14 , further comprising at least one optical filter that (a) conditions light reflected from the skin detected by the camera; or (b) conditions light from a built-in flash or an external illumination system. 
     
     
         21 .- 42 . (canceled)