Как получить заголовок Content-Type?

print_r(get_headers("http://instantcms.ru/upload/userfiles/3851/big_list_p_w.jpg"))

Array ( [0] => HTTP/1.1 200 OK [1] => Server: nginx [2] => Date: Tue, 20 Jan 2015 21:10:05 GMT [3] => Content-Type: image/jpeg [4] => Content-Length: 215201 [5] => Last-Modified: Tue, 20 Jan 2015 08:20:53 GMT [6] => Connection: close [7] => Expires: Wed, 21 Jan 2015 02:10:05 GMT [8] => Cache-Control: max-age=18000 [9] => Accept-Ranges: bytes )

echo get_headers("http://instantcms.ru/upload/userfiles/3851/big_list_p_w.jpg", 1)['Content-Type'];