How to measure total area of the child objects using RelateObject module

Hi everyone,

I was wondering if someone could advise me on how to measure the area of the child objects within each parent object that are created and counted using the RelateObjects module? It only counts them, but I need the total area occupied by them. Thanks!

There are several ways to do this:

  1. For the easiest approach you don’t need to relate the child objects. Just create a binary mask from all the child objects in the whole image. For the sake of the example, assume your child objects are spots and you now have a binary image called SpotMask. Assuming you have identified the parent objects (lets call them Cells), you can use the MeasureObjectIntensity module and select the Cells as objects and the SpotMask image as the one to be measured. The area covered by spots per cell will be the integrated intensity of the SpotMask image for this cell.
  2. If you want to use RelateObjects, export the per cell results as .csv file. The table with the results for the child objects will have a column with the parent id. You can group the child objects by image cycle and parent ID and sum the area measurment. A suitable tool to do this would be R or Python pandas. It should also be possible in Excel, but I can’t give advice on that.

Just to give you background of what I am doing because I am not entirely sure how I can achieve the first one. I have a timelapse where I have T cells infiltrating into organoids and I need the total T cell area within each organoid over time. As for the second one I feel like i have tried that but I get an error message every time and the child objects measurement document is always empty. It gives me a count of child objects in the parent object but for me thats not good enough because the separation of objects isnt very good as some of the infiltration is very dense so I need total area which it doesnt seem to give me anywhere.

The first approach should work if you can segment both the organoids and the T cells.
Assume you have a set of objects called organoids and a set call tcells.
Use ConvertObjectsToImage, choose objects tcells and select binary image. Name the output image binarytcell or something. Then use MeasureObjectIntensity, select the image binarytcell and the objects organoids. This should produce a meurement for the total (or integrated) intensity of binarytcell in each organoid, correspoding to the number of pixels in that object. You need to make sure you select this in the exports in ExportToSpreadsheet.