Susceptibility-weighted
imaging (SWI) is an emerging magnetic resonance imaging (MRI) technique that
exploits the susceptibility differences between the tissues. SWI provides the
enhancement of small vessels and microhemorrhages and detection of iron in the
brain. These characteristics permit SWI to show anatomical and functional
heterogeneity of brain tumors by exquisite sensitivity to the blood products
and venous vasculature. The aim of this study is to determine whether the distribution
pattern of intratumoral susceptibility sign (ITSS) derived from SWI could differentiate
glioblastoma multiforme (GBM) and single brain metastasis. We investigated the distribution
patterns of ITSS of the tumors and applied an ITSS grading system based on the
degree of the ITSS. Then, we compared the grade of the visibility of ITSS in
the central portion of tumors (CITSS) and in the tumor capsular area (PITSS) on
SWI in consensus. In clinical use, SWI is also useful for differentiating GBMs from
metastases.