ACNE IMAGING METHODS AND APPARATUS

• US 20150374277A1
• Filed: 04/15/2015
• Published: 12/31/2015
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: Canfield Scientific Incorporated
• Original Assignee: Canfield Scientific Incorporated
• Inventors: PATWARDHAN, Sachin V.
• Granted Patent: US 10,368,795 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2576/02 specially adapted for a particular organ or body part
• CPC Class Codes: A61B 5/0013 Medical image data A61B1/00011, A61B6/56, A61B8/56 take precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• CPC Class Codes: A61B 5/0077 Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/443 Evaluating skin constituents, e.g. elastin, melanin, water
• CPC Class Codes: A61B 5/444 Evaluating skin marks, e.g. mole, nevi, tumour, scar
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence

Abstract

Methods and apparatus are described for detecting acne, particularly in its earliest stages before any humanly visible or palpable manifestations thereof have emerged. An arrangement is described in which a green fluorescence image of an area of skin illuminated with blue light is captured and processed to detect the presence of microcomedones. The captured green fluorescence image is corrected for the non-uniform distribution of excitation light on the surface of the illuminated area of skin. Fluorescent spots are then detected in the corrected image. The subset of fluorescent spots having an intensity lower than an intensity threshold and an area smaller than an area threshold are selected as representative of candidate microcomedones. The subset can be further refined by eliminating fluorescent spots that have irregular shapes, are associated with inflammation, or exhibit comedone features. Additional filtering can be applied by selecting those spots whose locations correspond to those of pores. A dermatoscope with a blue illumination source and a green-filtered viewer allows live imaging of skin spots indicative of acne, including microcomedones not otherwise visible with the naked eye.

Claims

1. A method of imaging microcomedones in skin comprising:

illuminating the skin with a blue light;

capturing an image of the illuminated skin through a green filter; and

performing a further operation on the image including at least one of storing, processing, displaying and communicating the image.

13. The method of claim 1 comprising comparing the captured image with a stored image.

2. The method of clam 1 comprising:

correcting the captured image to generate a corrected image;

detecting fluorescent spots in the corrected image;

selecting a subset of the detected fluorescent spots, including selecting spots having at least one of an intensity less than an intensity threshold and an area smaller than an area threshold;

generating a further image of the skin indicating the subset of spots as possible microcomedones.

3. The method of claim 2, wherein selecting the subset of spots includes selecting spots having regular shapes.

4. The method of claim 2, wherein selecting the subset of spots includes selecting spots that are not associated with inflammation or that do not have comedone features.

5. The method of claim 2 comprising detecting pores in the skin, wherein selecting the subset of spots includes selecting spots corresponding to the detected pores.

6. The method of claim 2, wherein the blue light has a wavelength between 380 nm and 430 nm.

7. The method of claim 2, wherein the green filter has a center wavelength between 525 nm and 575 nm.

8. The method of claim 2, wherein the intensity threshold is 60% to 80% of full scale intensity.

9. The method of claim 2, wherein the area threshold is at least one of 70% to 90% of the median and 120% to 140% of the mean size of the subset of spots.

10. The method of claim 2, wherein correcting the captured image includes normalizing the captured image against at least one of a chromophore distribution image and an excitation image.

11. The method of claim 10, wherein the chromophore distribution image indicates the distribution in the skin of at least one of hemoglobin and melanin.

12. The method of claim 10, wherein the excitation image is an image of the skin captured while illuminating the skin with the blue light.

14. The method of claim 2 comprising comparing the further image with a stored image.

15. A dermatoscope comprising:

a viewing opening;

a light source arranged about the viewing opening; and

a filter for filtering light passing through the viewing opening,

wherein light of a blue wavelength is emitted from the dermatoscope when the light source is activated, and wherein the filter passes light of a green wavelength.

16. The dermatoscope of claim 15, wherein the light source comprises at least one of a blue light emitting light source and a blue filter.

17. The dermatoscope of claim 15, wherein the blue light has a wavelength between 380 nm and 430 nm.

18. The dermatoscope of claim 15, wherein the green filter has a center wavelength between 525 nm and 575 nm.