Sandrone on "[Plugin: WordPress SEO by Yoast] Problems with tag for images in relief."

Hi!
I'm having problems with images in relief .
why if I insert an image in relief in the pages and insert all the tags, the analysis of the plugin yaost tells me that there is no image on the page? How to solve this problem?
Thanks
Kind regards,

http://wordpress.org/extend/plugins/wordpress-seo/