%0 Journal Article
%A Wagenknecht, Gudrun
%A Kaiser, Hans-Jürgen
%A Mottaghy, Felix M.
%A Herzog, Hans
%T MRI for attenuation correction in PET: methods and challenges
%J Magnetic resonance materials in physics, biology and medicine
%V 26
%N 1
%@ 1352-8661
%C Heidelberg
%I Springer
%M FZJ-2013-01090
%P 99-113
%D 2013
%X Abstract In current combined PET/MR systems, PET attenuation correction is based on MRI, since the small bore insideMRI systems and the strongmagnetic field do not permit a rotating PET transmission source or a CT device to be integrated. Unlike CTmeasurements in PET/CT scanners, the MR signal is not directly correlated to tissue density andthus cannot be converted by a simple transformation of intensity values. Various approaches have been developed based on  templates, atlas information, direct segmentation of T1-weighted MR images, or segmentation of images from special MR sequences. The advantages and disadvantages of these approaches as well as additional challenges will be discussed in this review.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid: 23179594
%U <Go to ISI:>//WOS:000314888300009
%R 10.1007/s10334-012-0353-4
%U https://juser.fz-juelich.de/record/131826