Early differentiation of neurodegenerative diseases using the novel QSM technique: what is the biomarker of each disorder?

Table 11 Algorithms for implementing each stage of QSM reconstruction based on the method of research projects reviewed in this study.

	Cogswell et al. [8]	Gong [43]	Kim et al. [45]	Moon et al. [47]	Acosta-Cabronero et al. [44]	Au et al. [49]	Li et al. [52]	Fedeli et al. [54]	Ide et al. [55]
QSM Compution	Sparse linear equations and least squares (LSQR) method	Using an iLSQR algorithm	Morphology Enabled Dipole Inversion (MEDI)	To calculate the quantitative susceptibility map (QSM)	Truncated k-space division method	Streaking artifact reduction for QSM (STAR-QSM)	L1-norm total-variationbased regularization algorithm	Streaking artifacts reduction (STAR) algorithm	Morphology enabled dipole inversion (MEDI)
Background Phase Removal	–	Spherical mean value filtering with an initial kernel width of 30 voxels and the kernel width decreasing toward the tissue boundary	Projection onto dipole fields (PDF)	By using projection onto the dipole field (PDF)		Variable spherical kernel size (V-SHARP) method	RE-SHARP	V-SHARP
Phase Unwrapping	Laplacian-based	Using a Laplacian-based phase unwrapping algorithm		Performing nonlinear fit to the multi-echo data	The Laplacian-based method	Laplacian-based algorithm	Laplacian-based algorithm	Laplacian-based phase unwrapping
Brain tissue mask Extraction	Align the TIV mask with the magnitude and phase GRE images	Using magnitude image			Brain extraction tool (BET)

	Shahmaei et al. [51]	Pu et al. [50]	Spincemaille et al. [33]	Li et al. [34]	Sun and Wilman [32]	Li et al. [35]	Li et al. [73]
QSM Compution		Using fast STAR-QSM algorithm	The morphology-enabled dipole inversion (MEDI) algorithm	Modified structural feature based collaborative reconstruction algorithm (SFCR)	With regularization parameter of 5 \(\times \) 10^–4 and total variation technique	Truncated k-space division (TKD) based inverse filtering technique	Using streaking artifact reduction
Background Phase Removal	Using a high pass filter and a SHARP filter	V_SHARP method	The projection onto dipole field algorithm to yield the local field	V-SHARP method	Regularization enabled sophisticated harmonic artifact reduction for phase data (RESHARP)	The sophisticated harmonic artifact reduction (SHARP)	Using the V_SHARP method
Phase Unwrapping		Laplacian based phase unwrapping		Using Laplacian based	Laplacian based phase unwrapping	3D phase unwrapping algorithm (3DSRNCP) skipped for the simulated data too	Laplacian based phase unwrapping
Brain tissue mask Extraction	Brain extraction tool (BET)	Brain extraction tool (BET)	Brain extraction tool (BET)		Brain extraction tool (BET)	Brain extraction tool (BET)	Brain extraction tool (BET)

ISSN: 1471-2202