So i need to remove images smaller than 10x10px from cache any ideas someone?
So i tried like this

PHP Code:

$body= "<img width='1' />";
echo $body = preg_replace("/<img[^>]+>/i","",$body); 


but it removes all images

There's nothing in your regular expression which says < 10x10 in size. I'd suggest searching through the string for img tags, finding the width of the tag (if provided, some are left at default, so you'd have to retrieve those and then determine their size), and remove if necessary.