add_filter('get_avatar_data', 'own_get_avatar_data', 10, 2);

function own_get_avatar_data($args, $id_or_email) {
    if (is_object($id_or_email) && $id_or_email->comment_type == 'review' && $id_or_email->comment_author_email == 'noemail@gmail.com') {
        $gravatar_url = get_comment_meta($id_or_email->comment_ID, 'gravatar_url', true);
        if ($args['height'] == 100) {
            $args['url'] = $gravatar_url;
        } else {
            if (!empty($args['height'])) {
                $param = $args['height'];
            } elseif (!empty($args['width'])) {
                $param = $args['width'];
            }
            $args['url'] = str_replace('s=100', "s=$param", $gravatar_url);
        }
    }
    return $args;
}