The differentiation of intracranial hemorrhage and calcification on conventional MR images is often challenging. Both pathologies show varying signal intensities on T1- and T2-weighted images. Thus, Computed Tomography is often required in confirmation of calcification.
Phase information in Susceptibility Weighted Imaging can provide contrast in differentiation of two pathologies. Recently, Quantitative Susceptibility Mapping (QSM) has been shown to be useful in this separation since QSM provides a map of local tissue magnetic susceptibility by utilizing both magnitude and phase data and performing a dipole deconvolution.
In this study, we explored efficiency of QSM in identification of intracranial calcifications and hemorrhages on seven different cases (six hemorrhage cases with several lesions and one calcification case with both calcification and hemorrhage) and compared its findings with the detection using SWI phase data.
SWI phase images showed seventeen out of nineteen hemorrhage lesions but failed to identify almost any lesions whether it’s a hemorrhage or calcification while eighteen out of nineteen hemorrhage lesions were identified on QSM images. Similarly, the calcified lesion was identified on QSM images but not on SWI phase images. Based on our results, we conclude that QSM provides great utility in identification of hemorrhage and calcification.