Diagnostic ultrasound ( PDFDrive )

1684 PART V Pediatric Sonography
A B C
D
E
F
G H I
FIG. 49.16 Lipomyelocele. (A) Newborn with subcutaneous mass (white arrow) over the right sacrum and deviated gluteal cleft. (B) Sagittal
view demonstrates a low-lying tethered cord that ends at S1 (arrow points to the cord). There is a terminal placode, and the placode-lipoma (L)
interface lies within the canal. The lipoma and the ibrofatty ilum terminale cannot be separated on this view. There is a small amount of luid
ventral to the lipoma (small white arrows). (C) Sagittal view shows luid (small white arrows) extending through a defect in the right posterior
elements of S2 and into the subcutaneous lipoma. (D) Transverse view showing intradural lipoma (L) extending dorsal and inferior to the conus
medullaris. (E) Transverse view of the lipoma shows a central, tubular hypoechoic structure with more echogenic margins (black arrow), which
corresponds to the ibrofatty ilum. Note the intact cartilaginous posterior elements. (F) Transverse view at the level of the small right S2 posterior
element defect (outlined by *). Note small amount of luid extending in the central aspect of the subcutaneous mass (small white arrows). Transverse
images are oriented with the right side of the patient to the left of the screen to maintain consistency with the position of the subcutaneous mass
on the initial photograph. (G) Transverse view at the level of the subcutaneous mass shows central hypoechoic luid (white arrowhead) and subcutaneous
lipoma (L). (H) Transverse view at the level of the subcutaneous lipoma (L). (I) Sagittal T2 weighted image with fat saturation demonstrates
the tip of the conus at the lumbosacral junction, and a hypointense terminal lipoma adjacent to the ilum terminale. The subcutaneous mass is not
seen at this level because it was to the right of midline. See also Video 49.4, Video 49.5, and Video 49.6.
lumbosacral level, they are designated terminal myelocystoceles
(Fig. 49.18); these are quite rare. 63 he diagnosis can be established
with ultrasound or MRI when the low-lying cord terminus ends
in a cyst that is in communication with the central canal of the
spinal cord (syringocele). Expanded subarachnoid space (meningocele)
surrounds the distal cord and terminal cyst. Fluid within
the terminal cyst does not communicate with the expanded
subarachnoid space. hey have a high association with cloacal
exstrophy. 64-66
Closed Spinal Defects Without a
Subcutaneous Mass
Simple Dysraphic States
Filum terminale lipomas are characterized by ibrolipomatous
thickening of the ilum terminale. Both the intradural and
extradural portions of the ilum terminale can be involved, and
the amount of fatty iniltration varies. Frequently the ilum is
slightly of midline as seen on transverse images. In this entity,