M Aznar*1, J Polf2, M Akselrod3, C Andersen1, S Back4, L Boetter-Jensen1, S Mattsson4, S McKeever2, J Medin4, (1)Risoe National Laboratory, Roskilde, Denmark, (2)Oklahoma State University, Stillwater, OK, (3) Landauer Inc., Stillwater, OK, (4)Malmoe University Hospital,Malmoe, Sweden