printing pdf without background colour

[amadeusamadeus]

Hi, my prof posts many x-rays in his pdf files which I need to print for class. However the black background of all these images is killing my ink supply. Is there any way I can print these pdf files without their black background? I don't see any such options in Preview, but I do have access to CS5 Design Premium if perhaps someone knows a technique through one of the programs in there. Any assistance is greatly appreciated, thanks.

 

[DolemiteJackson]

There is a program the lets you edit PDFs. Perhaps it will allow you to edit the
background. I think it's called PDFpen.