function plt_hide_instant_images_menus() {
//Hide the "Media → Instant Images" menu.
remove_submenu_page('upload.php', 'instant-images');
//Hide the "Settings → Instant Images" menu.
remove_submenu_page('options-general.php', 'instant-images-settings');
}
add_action('admin_menu', 'plt_hide_instant_images_menus', 11);