Diffusion-weighted imaging of the spinal cord in children after prenatal myelomeningocele repair.

BACKGROUND

Little is known about the impact of spinal cord microstructural alterations after prenatal myelomeningocele (MMC) repair and their associations with neurological clinical assessments.

OBJECTIVE

To assess spinal cord diffusivity using diffusion-weighted imaging (DWI) obtained between 10 months and 30 months of age in children who underwent prenatal MMC repair, and to explore associations with neurological clinical assessments.

MATERIALS AND

METHODS

This retrospective cohort study included children who underwent prenatal MMC repair from November 2011 to May 2023. All children met the Management Of Myelomeningocele Study (MOMS) inclusion criteria. DWI (b=0 s/mm2 and 800 s/mm2) was performed between 10 months and 30 months of age, and apparent diffusion coefficient (ADC) values were obtained at the level of the spinal lesion. Neurological clinical assessments included intact S1 motor and sensory level, need for anticholinergic therapy or clean intermittent catheterization at the evaluation closest to 12 months, and ambulatory status at the evaluation closest to 30 months. Associations between ADC values (expressed as median [interquartile range]) and neurological clinical assessments were evaluated using the Mann-Whitney U test. A P-value <0.05 was considered significant.

RESULTS

Thirty-six children were included (23 fetoscopic, 13 open-hysterotomy repairs). ADC values were significantly higher in children with intact S1 motor function (1.25 [1.00-1.89] vs 1.19 [1.00-1.30]×10-3 mm2/s, P=0.01), intact S1 sensory level (1.36 [1.12-1.74] vs 1.21 [1.04-1.38]×10-3 mm2/s, P=0.02), no anticholinergic therapy (1.31 [1.13-1.70] vs 1.22 [1.04-1.40]×10-3 mm2/s, P=0.04), no catheterization (1.33 [1.04-1.74] vs 1.21 [1.12-1.32]×10-3 mm2/s, P=0.04), and independent ambulation (1.36 [1.04-1.89] vs 1.19 [1.00-1.46]×10-3 mm2/s, P=0.02).

CONCLUSION

Lower ADC values at the lesion level were associated with worse neurological and urological clinical assessments in children after prenatal MMC repair, suggesting that DWI may provide imaging biomarkers of spinal cord integrity.