Are you asking about meta files or meta tags (such as keywords)?
If it is meta tags such as keywords, then yes... you could create a page called, say, "header code" in which you are going to have all the elements you may want to update dynamically in the header code... and then just add the PHP echo statement as directed in the place where your keywords would go. If you wanted to have all the pages have a different set of keywords, then you would simply need to add more content areas to update in your header code page on the CMS side.
Best regards,
Brian