Dataset Information

Inherent and unpredictable bias in multi-component DESPOT myelin water fraction estimation.

ABSTRACT: Multicomponent driven equilibrium steady-state observation of T1 and T2 (mcDESPOT) aims to quantify the Myelin Water Fraction (MWF) using a two-pool microstructural model. The MWF has been used to track neurodevelopment and neurodegeneration and has been histologically correlated to myelin content. mcDESPOT has a clinically feasible acquisition time and high signal-to-noise ratio (SNR) relative to other MWF techniques. However, disagreement exists in the literature between experimental studies that show MWF maps with plausible grey matter-white matter (GM-WM) contrast and theoretical work that questions the accuracy and precision of mcDESPOT. We demonstrate that mcDESPOT parameter estimation is inaccurate and imprecise if intercompartmental exchange is included in the microstructural model, but that significant bias results if exchange is neglected. The source of apparent MWF contrast is likely due to the complex convergence behaviour of the Stochastic Region Contraction (SRC) method commonly used to fit the mcDESPOT model. mcDESPOT-derived parameter estimates are hence not directly relatable to the underlying microstructural model and are only comparable to others using similar acquisition schemes and fitting constraints.

SUBMITTER: West DJ

PROVIDER: S-EPMC7100802 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Inherent and unpredictable bias in multi-component DESPOT myelin water fraction estimation.

West Daniel J DJ Teixeira Rui P A G RPAG Wood Tobias C TC Hajnal Joseph V JV Tournier Jacques-Donald JD Malik Shaihan J SJ

NeuroImage 20190328

Multicomponent driven equilibrium steady-state observation of T<sub>1</sub> and T<sub>2</sub> (mcDESPOT) aims to quantify the Myelin Water Fraction (MWF) using a two-pool microstructural model. The MWF has been used to track neurodevelopment and neurodegeneration and has been histologically correlated to myelin content. mcDESPOT has a clinically feasible acquisition time and high signal-to-noise ratio (SNR) relative to other MWF techniques. However, disagreement exists in the literature between ...[more]

PMID: 30930311

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Dataset Information

Inherent and unpredictable bias in multi-component DESPOT myelin water fraction estimation.

Publications

Inherent and unpredictable bias in multi-component DESPOT myelin water fraction estimation.

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