How Do I Compare Two Total Body Images?

Lesion Matching automatically detects and matches skin lesions from similar images taken over time. The matched lesions are sorted based on the change and size of the matched lesions. To learn how to run the Lesion Matching algorithm, follow the instructions below:

  1. Access your patient’s total body photography profile and click the desired body section.
  2. Next, select the images you would like to compare. 
  3. Click Start Matching. Please wait a moment, as it may take time to process this request, depending on the number of spots on that patient. 
  4. If the images are different in size, DermEngine will automatically scale the image. In this case, a pop-up message will appear at the bottom of the page notifying you about automatic scale adjustments. To undo this action, click the button. 
  5. Once matched, you can use the lesion detection slide to adjust the number of lesions you want the algorithm to identify. 

    Definitions for the Lesion Detection Slider: 
    • Change - This shows the degree of change observed in each lesion pair.
    • Size - This indicates the relative diameter of each lesion.


      All detected spots will be paired in the viewing column on the right. Here, these will be sorted and color-coded based on the amount of change:

      1. Purple: Change detected
      2. Blue: Possible change detected 
      3. Grey: No change detected

      Notable mentions: there is a report mismatch tool that offers you the option to advise of any poor matches, missing pairs, or inaccuracies in change detection labels. 
  6. From here, you can review the list; clicking an image will provide you with the following options:
    1. Confirm Match
    2. Map
    3. Delete Match
    4. Not Changed or Changed.
  7. To get a better look at a spot, you can use the paired slider or scroll with your mouse to get a magnified view of both images at once.

    To learn how to add or remove lesion pairs click here.

    Click the following links below to learn how to perform different actions within the total body photography module: