retrieve image from rss reader

the code tries to load image :

var loader:URLLoader = new URLLoader();

loader.addEventListener(Event.COMPLETE, onLoaded);

lb.addEventListener(Event.CHANGE, itemChange);

function itemChange(e:Event):void

{

    tb.htmlText = imgTag;

    ta.htmlText = "<a href=\"" + lb.selectedItem.link + "\">" + lb.selectedItem.label + "</a>";

}

var xml:XML;

function onLoaded(e:Event):void

{

    xml = new XML(e.target.data);

    var il:XMLList = xml.channel.item; 

    for(var i:uint=0; i<il.length(); i++)

    {

        var desc:String = il.description.text();

        var startImg:Number = desc.indexOf("<");

        var endImg:Number = desc.indexOf(">");

        var imgTag:String = desc.substr(startImg, endImg-startImg+1);

        trace(imgTag);

lb.addItem({data:il.description.text(), link:il.link.text(),

                        label:il.title.text()}); 

    }

}

loader.load(new URLRequest("http://www.medicinenet.com/rss/general/cancer.xml"));

without image loading the code runs well :

var loader:URLLoader = new URLLoader();

loader.addEventListener(Event.COMPLETE, onLoaded);

lb.addEventListener(Event.CHANGE, itemChange);

function itemChange(e:Event):void

{

  ta.text = lb.selectedItem.data;

}

var xml:XML;

function onLoaded(e:Event):void

{

  xml = new XML(e.target.data);

  var il:XMLList = xml.channel.item;

  for(var i:uint=0; i<il.length(); i++)

  {

  lb.addItem({data:il.description.text(),

  label:il.title.text()});

  }

}

loader.load(new URLRequest("http://www.medicinenet.com/rss/general/cancer.xml"));