PMC10159279_01
Photographs at birth showing (a-1) a neural placode at the lumbosacral region with an open skin defect (15 x 25 mm) exposed to the surface and (a-2) the patient's lower limbs in the cross-legged position with severe flexor contractures. (b-1) Three-dimensional and (b-2) sagittal spinal computed tomography images showing a complete absence of the L1-L3 lumbar vertebrae and dislocation of the lower segment, which deviates anteriorly at the level of the absence. (c) Sagittal three-dimensional-heavily T2-weighted and (d) sagittal T1-weighted spoiled gradient-recalled echo images also demonstrated two completely separated spinal cord segments. The upper segment ends at T8, with a "cigar-shaped" appearance instead of the usual tapered conus (red arrow). The lower segment is located from L4 to S1, displaying an exposed placode (yellow arrow) lying flush with the skin surface with an underlying subarachnoid space, consistent with myelomeningocele.
SNI-14-149-g001.jpg
PMC10159279_01_SNI-14-149-g001.jpg
F1
Apgar score of 8 at 37 + 4 weeks of gestation. A skin defect (15 x 25 mm) associated with a dysplastic neural placode exposed to the surface was detected in the infant at the lumbosacral region without cerebrospinal fluid (CSF) leakage [Figure 1a-1]. The infant had spastic paraplegia and severe flexor contractures in the cross-legged position [Figure 1a-2], and the infant's anus was patulous with fecal incontinence. Spinal three-dimensional (3D) computed tomography revealed that the spinal column at L1-L3, including both vertebrae and posterior elements, was absent and that the lumbar spine below L4 and bifid sacrum deviated anteriorly [Figures 1b-1 and b-2]. T2-weighted images and 3D-T1-weighted images, showed that the spinal cord was divided into two segments above and below the spinal agenesis [Figures 1c and d, Figure 2a]. The upper segment seemed normal [Figure 2b-1], but the spinal cord abruptly ended with a "cigar-shaped" appearance at the lower thoracic and caudal regions [Figures 1c and d, Figures 2b-2 and b-3].
A sagittal view (a) and serial axial views (b-1-4) of 3D-hT2WI delineating detailed structures. (b-1) Normal appearance of upper spinal cord at T7 level. (b-2) Absence of band-like structure caudally to the upper spinal cord. (b-3) No signal intensity of CSF at the portion between the upper and lower dural sac. (b-4) Bundle of nerve roots (red arrow) in the subarachnoid space and the neural placode (red asterisk) attached to the skin surface. 3D-hT2WI: Three-dimensional heavily T2-weighted imaging, CSF: Cerebrospinal fluid.
SNI-14-149-g002.jpg
PMC10159279_01_SNI-14-149-g002.jpg
F2
The infant had spastic paraplegia and severe flexor contractures in the cross-legged position [Figure 1a-2], and the infant's anus was patulous with fecal incontinence. Spinal three-dimensional (3D) computed tomography revealed that the spinal column at L1-L3, including both vertebrae and posterior elements, was absent and that the lumbar spine below L4 and bifid sacrum deviated anteriorly [Figures 1b-1 and b-2]. T2-weighted images and 3D-T1-weighted images, showed that the spinal cord was divided into two segments above and below the spinal agenesis [Figures 1c and d, Figure 2a]. The upper segment seemed normal [Figure 2b-1], but the spinal cord abruptly ended with a "cigar-shaped" appearance at the lower thoracic and caudal regions [Figures 1c and d, Figures 2b-2 and b-3]. The lower segment originated from around the L4 level, of which caudal end was a neural placode without cystic component at the S1 level [Figure 2b-4]. These features were consistent with MMC. Neither band-like structures nor delineation of the intensity of CSF was detected between the upper and lower spinal cords [Figures 2b-2 and b-3].
(a) An intraoperative picture of the neural placode resected from the attached skin, demonstrating proximal spinal cord and nerve roots arising from the dorsal aspect of the placode. Histopathological findings of the resected margin of the neural placode stained with hematoxylin and eosin (b) and immunostained for glial fibrillary acidic proteins (GFAP, c). The specimen comprises a GFAP-immunopositive neuroglial tissue including mature neurons and an adjoining fibrotic leptomeningeal tissue.
SNI-14-149-g003.jpg
PMC10159279_01_SNI-14-149-g003.jpg
F3
The upper segment seemed normal [Figure 2b-1], but the spinal cord abruptly ended with a "cigar-shaped" appearance at the lower thoracic and caudal regions [Figures 1c and d, Figures 2b-2 and b-3]. The lower segment originated from around the L4 level, of which caudal end was a neural placode without cystic component at the S1 level [Figure 2b-4]. These features were consistent with MMC. Neither band-like structures nor delineation of the intensity of CSF was detected between the upper and lower spinal cords [Figures 2b-2 and b-3]. The open neural placode was circumferentially resected from the surrounding skin, and proximal spinal cord and nerve roots continuing with the ventral side of the neural placode were observed in the open dural sac filled with CSF [Figure 3a]. The histopathological examination of the resected tissue from the margin of the neural placode showed a glial fibrillary acidic protein-immunopositive neuroglial tissue adjoining a fibrotic leptomeningeal tissue [Figures 3b and c].