mPDF turning square image into a circle

Is it at all possible to have an image be a circle in mPDF? Looked all over and couldn't find any clear answers.

For me this image shows up fine, except that its a square and this should make it a circle.

css

img{
    width: 150px;
    height: 150px;
    border-radius: 150px;
}

php

$inputPath = '../web_content/cool_cat.jpg';
<div class="profile_img">
    <img src="'.$inputPath.'"/>
</div>