Synthetic MR Imaging-Based WM Signal Suppression Identifies Neonatal Brainstem Pathways in Vivo

Area of Science:

• Radiology and Imaging
• Neuroscience
• Pediatric Imaging

Background:

• Multidynamic multiecho sequence imaging allows reconstruction of multiple MR contrasts from a single scan.
• Synthetic MRI-based WM signal suppression (syWMSS) utilizes a short inversion time (TI) to suppress myelin-related signals.

Purpose of the Study:

• To investigate the feasibility of syWMSS for identifying early myelinating brainstem pathways in neonates.
• To compare the efficacy of syWMSS with conventional T1- and T2-weighted MR imaging sequences.

Main Methods:

• Analysis of 31 neonatal MR imaging cases with multidynamic multiecho data.
• Generation of syWMSS data using SyMRI software (TR/TE/TI = 3000/5/410 ms).
• Two raters identified specific early myelinating brainstem pathways on syWMSS and reference standard contrasts.

Main Results:

• syWMSS data enabled reliable identification of the decussation of the superior cerebellar peduncle, medial lemniscus, and medial longitudinal fascicle by both raters.
• Identification rates for these pathways were significantly higher on syWMSS compared to T1-weighted and T2-weighted contrasts.
• The central tegmental tract was also identified on syWMSS data, though with slightly lower rates than other pathways.

Conclusions:

• syWMSS is a feasible and effective imaging technique for studying early myelinating brainstem pathways.
• Myelin signal suppression in MR imaging enhances the sensitivity of assessing myelination patterns in early cerebral development.