Hi Hamid
It should be something like:
var
  atag: PIEDicomTag;
  aMemStream : TMemoryStream;
begin
  atag := MainForm.ImageEnMView1.MIO.Params[0].DICOM_FindTag($7FE0,$0010);
  if atag = nil then
    raise Exception.create( 'Invalid Tag' );
  aMemStream := TMemoryStream.Create();
  aMemStream.Write( atag^.Data, atag^.DataLen );
  aMemStream.Position := 0;
  // Do something with aMemStream
  aMemStream.Free;
Nigel 
Xequte Software
www.xequte.com
nigel@xequte.com