Dynamic change of page header in XSLT
I want same Image to be in Header however the content over image should change dynamically according to value in XML node
As @potame already mentioned in comments, and are designed specially for this. Since you don't give any xml I created a simple example to show how to retrieve the marker and the logic behind it then you should be able to adapt to your code.
Then somewhere in your code (probably in the region-body you will set the marker value (In your case it would be a path url if I understand your question) depending on your wanted condition. Something like :