<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bagory, M.</style></author><author><style face="normal" font="default" size="100%">Françoise Durand-Dubief</style></author><author><style face="normal" font="default" size="100%">Danielle Ibarrola</style></author><author><style face="normal" font="default" size="100%">Christian Confavreux</style></author><author><style face="normal" font="default" size="100%">Dominique Sappey-Marinier</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">''Absolute'' quantification in magnetic resonance spectroscopy: validation of a clinical protocol in multiple sclerosis</style></title><secondary-title><style face="normal" font="default" size="100%">Conf Proc IEEE Eng Med Biol Soc</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">categ_mixte</style></keyword><keyword><style  face="normal" font="default" size="100%">Imagerie cérébrale</style></keyword><keyword><style  face="normal" font="default" size="100%">imagerie_spectroscopique_RMN</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year></dates><volume><style face="normal" font="default" size="100%">2007</style></volume><pages><style face="normal" font="default" size="100%">3458–61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MRS allows to measure cerebral metabolites, thus helping to characterize brain disease diagnosis and followup. Metabolite concentration quantification is usually based on metabolite ratio referring to creatine. If this metabolite concentration is supposed to be constant, it may vary in pathological processes. Therefore, ``absolute'' concentration methodology is needed. The aim of this study is to validate a clinical ``absolute'' quantification protocol through the development of an external metabolic phantom, calibration and correction, and the investigation of reproducibility issues. When phantom stability was investigated by a short-term and a long-term reproducibility study, both Standard Deviations (SD) were in agreement with literature values. This ``absolute'' quantification method was applied to patients with Multiple Sclerosis (MS). The results show a significant decrease in both N-Acetyl Aspartate (NAA) and choline concentrations.</style></abstract></record></records></xml>