In Word 2016 you can go to the File tab and down the bottom on the right side there is a little line that says "Edit Links to Files". You can click on that and it summarises all the links (including cross-references). If you selected the linked graphic before going there it should be selected in the list. You can find the command with the same name if you wanted to add it to your QAT or do a keyboard shortcut for it.

I think this is the same in Word 2013.

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Andrew Lockton
Chrysalis Design, Melbourne Australia