how to generate random spots in 3D images by macro

Posted by Wanzhu on
URL: http://imagej.273.s1.nabble.com/how-to-generate-random-spots-in-3D-images-by-macro-tp5019155.html

I have a 3D image and I demarcated a 3D ROI. I want to generate 200 spots (each spot's diameter is 4 um which represent cells) only placed in the 3D ROI. So I can further import this images to Imaris and calculate the distance between these simulated spots and actual blood vessels in ROI.  
I have no experience in Macro,  I really appreciate it if you can help me. Thank you.