PMC8942195_01
(a) Prenatal half-Fourier acquisition single-shot turbo spin-echo sequence image at 34 weeks of gestation revealing skin-covered CSF-filled mass at the lumbosacral region (arrow) and an abdominal wall defect with omphalocele (arrowheads). (b-d) Photographs of the patient at birth showing omphalocele (white arrow), exstrophy of the cloaca (arrowheads), imperforate anus (dotted white arrow), mass at the lumbosacral region covered with normal skin (black arrow), and bilateral club foot (dotted black arrows). (e) Photograph of the patient at 5 months after birth showing partially inadequate epithelialization of the omphalocele surface. (f and g) MRI at 5 months after birth. 3D-T1-weighted (f-1) and 3D-heavily T2-weighted magnetic resonance imaging (3D-hT2WI) (f-2, g-1 and g-2) revealing a lowlying hydromyelic cord extruding into the extraspinal space with trumpet-shaped cystic cavity (myelocystocele; arrowhead) containing neural placode (arrow) and surrounded by large subarachnoid space (asterisk) extending posterocaudally into the extraspinal region. (h) Photograph of the patient at 9 months after birth showing the epithelialization of the protuberant omphalocele sac. Sagittal views (i) and axial views (j) of 3D-hT2WI at 9 months after birth (just before surgery). Note the more enlarged subarachnoid space (asterisk) compared to the myelocystocele (arrowhead). CSF: Cerebrospinal fluid, 3D-hT2WI: Three-dimensional heavily T2-weighted imaging.
SNI-12-628-g001.jpg
PMC8942195_03_SNI-12-628-g001.jpg
F1
Muscular coverage on the dural sac was achieved only at the rostral portion because there was no sufficient volume of the paraspinous muscles to cover the surgical site [Figure 1j].
PMC8942195_02
(a) Prenatal half-Fourier acquisition single-shot turbo spin-echo sequence image at 34 weeks of gestation revealing skin-covered CSF-filled mass at the lumbosacral region (arrow) and an abdominal wall defect with omphalocele (arrowheads). (b-d) Photographs of the patient at birth showing omphalocele (white arrow), exstrophy of the cloaca (arrowheads), imperforate anus (dotted white arrow), mass at the lumbosacral region covered with normal skin (black arrow), and bilateral club foot (dotted black arrows). (e) Photograph of the patient at 5 months after birth showing partially inadequate epithelialization of the omphalocele surface. (f and g) MRI at 5 months after birth. 3D-T1-weighted (f-1) and 3D-heavily T2-weighted magnetic resonance imaging (3D-hT2WI) (f-2, g-1 and g-2) revealing a lowlying hydromyelic cord extruding into the extraspinal space with trumpet-shaped cystic cavity (myelocystocele; arrowhead) containing neural placode (arrow) and surrounded by large subarachnoid space (asterisk) extending posterocaudally into the extraspinal region. (h) Photograph of the patient at 9 months after birth showing the epithelialization of the protuberant omphalocele sac. Sagittal views (i) and axial views (j) of 3D-hT2WI at 9 months after birth (just before surgery). Note the more enlarged subarachnoid space (asterisk) compared to the myelocystocele (arrowhead). CSF: Cerebrospinal fluid, 3D-hT2WI: Three-dimensional heavily T2-weighted imaging.
SNI-12-628-g001.jpg
PMC8942195_03_SNI-12-628-g001.jpg
F1
Muscular coverage on the dural sac was achieved only at the rostral portion because there was no sufficient volume of the paraspinous muscles to cover the surgical site [Figure 1j].
PMC8942195_03
(a) Prenatal half-Fourier acquisition single-shot turbo spin-echo sequence image at 34 weeks of gestation revealing skin-covered CSF-filled mass at the lumbosacral region (arrow) and an abdominal wall defect with omphalocele (arrowheads). (b-d) Photographs of the patient at birth showing omphalocele (white arrow), exstrophy of the cloaca (arrowheads), imperforate anus (dotted white arrow), mass at the lumbosacral region covered with normal skin (black arrow), and bilateral club foot (dotted black arrows). (e) Photograph of the patient at 5 months after birth showing partially inadequate epithelialization of the omphalocele surface. (f and g) MRI at 5 months after birth. 3D-T1-weighted (f-1) and 3D-heavily T2-weighted magnetic resonance imaging (3D-hT2WI) (f-2, g-1 and g-2) revealing a lowlying hydromyelic cord extruding into the extraspinal space with trumpet-shaped cystic cavity (myelocystocele; arrowhead) containing neural placode (arrow) and surrounded by large subarachnoid space (asterisk) extending posterocaudally into the extraspinal region. (h) Photograph of the patient at 9 months after birth showing the epithelialization of the protuberant omphalocele sac. Sagittal views (i) and axial views (j) of 3D-hT2WI at 9 months after birth (just before surgery). Note the more enlarged subarachnoid space (asterisk) compared to the myelocystocele (arrowhead). CSF: Cerebrospinal fluid, 3D-hT2WI: Three-dimensional heavily T2-weighted imaging.
SNI-12-628-g001.jpg
PMC8942195_03_SNI-12-628-g001.jpg
F1
Muscular coverage on the dural sac was achieved only at the rostral portion because there was no sufficient volume of the paraspinous muscles to cover the surgical site [Figure 1j].
(a) Photograph of the patient in the prone position during the operation. Note the extended lumbosacral mass. (b) Intraoperative photograph (b-1) and schematic drawing (b-2) after stripping the SF from the huge MCW. (c) Intraoperative photograph (c-1) and schematic drawing (c-2) demonstrating the untethered NP including part of the MCW, and the terminal portion of the hydromyelic SC. The untethering site is indicated by dotted arrows. (d) Intraoperative photograph (d-1) and schematic drawing (d-2) after pia-to-pia neurulation of the neural placode (arrowhead) demonstrating lipofibrous layers (arrows) composing a part of MCW and joining to the dural sac used for the subsequent duraplasty. Note the enlarged subarachnoid space in the caudal part of the dural sac (asterisk). (e) Histopathology of the inner wall of the myelocystocele sac demonstrating the ependymal layer (Epen) with the surrounding neuroglial tissues (hematoxylin and eosin staining). MCW: Myelocystocele sac wall, SF: Subcutaneous fat, NP: Neural placode, SC: Spinal cord.
SNI-12-628-g002.jpg
PMC8942195_03_SNI-12-628-g002.jpg
F2
During surgery, the patient was placed prone with special management to protect his abdomen from pressure [Figure 2a]. The myelocystocele sac wall (MCW) was peeled off the overlying subcutaneous fat [Figure 2b], and a neural placode with a dilated central canal was revealed. The neural placode was untethered by resection of the nonfunctional portion of the MCW and reconstituted with pial suture [Figures 2c and d]. Duraplasty in a water-tight fashion was achieved using fibrous tissue which was in continuity with the dural sac and had composed part of the MCW [Figure 2d].
PMC8942195_04
(a) MRI after the first repair surgery for the CSF leakage showing the caudal subarachnoid space in the dural sac (asterisk) (a-1; 3D-hT2WI) and CSF leakage through the gaps between the subcutaneous tissue (black dotted arrow) (a-2; T2WI). Sagittal (b-1) and axial (b-2) views of 3D-hT2WI after the second repair surgery for CSF leakage revealing the deficit of the subcutaneous tissues and the dorsal aspect of the dural sac, which was covered with only thin tissue without muscle layers (white dotted arrow). Note the shortened terminal part of the reconstituted spinal cord and the dural sac (arrowhead). Sagittal (c-1) and axial (c-2) views of 3D-hT2WI 3 months after the third repair surgery (4 months after the untethering surgery) demonstrating the dorsal aspect of the dural sac covered with flaps of the gluteus muscles (arrow) without CSF leakage. CSF: Cerebrospinal fluid, 3D-hT2WI: Three-dimensional heavily T2-weighted imaging.
SNI-12-628-g003.jpg
PMC8942195_04_SNI-12-628-g003.jpg
F3
However, high-pressure CSF leakage continued [Figure 3a]. The terminal portion of the reconstituted placode was severed so that the caudal part of the enlarged dural sac extending posteriorly into the extraspinal region could shortly be reconstructed in the spinal canal [Figures 3a and b]. MRI at this time revealed that the part of subcutaneous fat had dissolved and disappeared [Figure 3b]. MRI 4 months after the untethering surgery revealed neither CSF leakage [Figure 3c] nor hydrocephalus.