Diffusion Weighted Imaging of the spinal cord in children after a prenatal myelomeningocele repair

Background Little is known about the impact of spinal cord microstructural alterations after prenatal myelomeningocele (MMC) repair and their association with neurological outcomes. Objective To assess spinal cord diffusivity using diffusion-weighted imaging (DWI) at 12 months of age in children who underwent prenatal MMC repair and to explore associations with clinical outcomes. Materials and Methods This retrospective cohort study included children who underwent prenatal MMC repair at XXXX between November 2011 and May 2023. All children met MOMS trial inclusion criteria. DWI was performed at approximately 12 months of age, and apparent diffusion coefficient (ADC) metrics were obtained at the level of the spinal lesion. Neurological outcomes included intact S1 motor and sensory level, need for anticholinergic therapy or clean intermittent catheterization at 12 months, and ambulatory status at 30 months. Associations between ADC (expressed as 10⁻⁶ mm²/s) and outcomes were assessed using the Mann-Whitney U test. Results Thirty-six children were included (23 fetoscopic, 13 open-hysterotomy repairs). ADC was significantly higher in children with intact S1 motor function (1.251 [1.001–1.891] vs. 1.193 [1.001-1.300], p = 0.01), intact S1 sensory level (1.362 [1.120–1.740] vs. 1.212 [1.041–1.378], p = 0.02), no anticholinergic therapy (1.315 [1.130–1.697] vs. 1.223 [1.041-1.400], p = 0.04), no catheterization (1.327 [1.041–1.739] vs. 1.212 [1.120–1.319], p = 0.04), and ambulatory status at 30 months (1.362 [1.041–1.891] vs. 1.187 [1.001–1.456], p = 0.02). Conclusion Lower ADC values at the lesion level were associated with adverse neurological and urological outcomes in children after prenatal MMC repair, suggesting that DWI may provide early imaging biomarkers of spinal cord integrity.