ImageJ: Precisely Placing ROI between Different Images

imagej

#1

I am trying to compare the change in intensity in a few locations in a series of radiographs. It is difficult to assess the validity of my data because the ROI is imprecisely placed between images. Currently, I am making the ROI, then opening the next image, and placing the ROI in approximately the same position. The frame of each radiograph is slightly shifted, so the ROI must be manually adjusted with each new radiograph. I tried using the grid, but it still seems too subjective.
image
Is there a way to have Image J recognize certain landmarks and position the ROI accordingly? Perhaps there is a way that I could manually measure from my own landmarks to precisely place the ROI?
My current methods are rough and not likely to be repeatable in future studies. Any help would be appreciated.


#2

Here is an ImageJ plugin which places ROI in the identical regions between images:
Easing ROI

Using it by clicking Plugins-Easing ROI-Easing ROI after compiled and installed correctly.

Hope it would help.


#3

If I understand correct, check the command:
Analyze > Tools > Synchronize Windows


#4

You could try putting the images into a stack and doing a registration, so that the positions of the objects will be aligned. Then you can use the same ROI position for all of the measurements.

The StackReg plugin is easy to use for this purpose. It is available in the BIG-EPFL update site in Fiji. (I recommend using the update site rather than downloading directlly from the StackReg website.)

Hope this helps.