key => value pair using variables

Question

So I have an array called $items, that I iterate unto:

foreach($area as $item) {
    $options["{$item['id']}"] = "{$item['name']} ({$item['id']})"; //pass
}

Each pass in the loop produces something like this:

[1] => string(18) "grand ballroom (1)"

But what I need is for it to be:

['1']=> string(18) "grand ballroom (1)"

How can I achieve this? Thanks!