neonatal spine Flashcards
When can we use sonography for evaluating the fetal spine?
infants under 6mo
surgical procedures
known spinal defects where an acoustic window is available
What is spinal dysraphism?
array of spinal abnormalities caused by inadequate or improper fusion of the NT in early fetal life
2 types: open + closed
Why would we need to perform an ultrasound on the spine?
spinal dysraphism: meningoceles, myelomeningoceles, lipomyelomeningoceles, lipomas
lumbosacral skin anomalies: pigmented spots, hairy nevus, dimples, hemangiomas, dermal sinuses
What is a syrinx?
a rare, fluid-filled cavity within the spinal cord
What patient position is used?
prone w/ towel or pillow under (rounds out back)
decub is also used “fetal position”
Slide 9-16
has stuff highlighted but it’s like labelling stuff
Spinal cord appears hypoechoic sonographically. T/F
true
The cord tapers to the
conus medullaris (L1 + L2)
What’s the measurement for filum terminale?
<2mm
What do nerve roots appear as sonographically?
small echogenic dots or clumps together
sometimes obscuring filum terminale
The cord is smaller in the cervical region, narrows in thoracic region and enlarges at the conus. True or false
False- it is larger in the cervical region and then narrows in the thoracic segment
When should the spinal cord terminate?
L1 + L2
What embryonic structure forms the spine?
ectoderm
Each end of the neural tube closes. If the anterior neuropore doesn’t close, what happens? The posterior neuropore?
anterior- anencephaly
posterior- spina bifida, p
Ventriculus terminalis is a normal variant. What is it?
a slight widening of the distal central canal
the echogenic walls of the central canal are slightly separated by anechoic fluid near the conus
doesn’t extend cranially into the the thoracic region
What is a filar cyst?
normal variant
ovoid midline anechoic structure just inferior to the tip of the conus
Where is spinal dysraphism most common?
lower spine
Open spinal dysraphism:
neural tissue exposed without skin covering
myeloceles, myelomeningoceles
inc. AFP + maternal serum + amniotic fluid
Closed spinal dysraphism:
skin covered spinal abnormality
can be with or without mass
CSD with mass can be what? (3)
lipomyelocele
lipomyelomeningocele
myelocystocele
CSD without a mass can be what? (4)
tethered cord
spinal lipoma
diastomyelia
dorsal dermal sinus
present as cutaneous markers (hair tufts, dimples or pits, hemangiomas, etc.)
What’s the difference between a myelocele and a myelomeningocele?
myelocele is a herniation of the meninges through the dura mater and in an MMC it also includes the neural tissue
What is more common, a myelocele or MMC?
MMC
MMC is assoicated with?
Arnold Chiari II malformation
What sonographic signs are seen with Arnold Chiari II malformation?
fruit sign
lemon + banana
Banana shape refers to what structure?
cerebellum
Tethered cords are almost always associated with?
dysraphic anomalies
What symptoms does a child with a tetherd cord present ?
neurological symptoms- limb, bowel or urinary dysfunction
skin markers
Sono appearance of tethered cord:
spinal cord in low lying postition (at or below L3)
conus is elongated and pulled dorsally
nerve roots have decreased movements
thick filum terminale
What is diastomyelia?
separation of the spinal cord into two hemicords
split by a bony or fibrous septum
Where does diastomyelia most often occur?
thoracolumbar region
usually has a cutaneous marker
usually reunite distally
What is a dorsal dermal sinus?
a thin, epithelial lined tract that passes from the skin toward the spinal canal
mostly in lumbosacral region
at risk for meningitis
What is the most common reason for an infant to be referred to US (for the spine)?
sacral dimple/pit
Where is a sacral dimple located?
<2.5 from the anus
What should a sacral dimple not be confused with?
DDS because it has no connection to the spine
Intradural lipoma:
lies within the spinal cord and is completely confined by the dura
Lipomas of the filum terminale:
presents as a thickened FT >2mm, or a small echogenic fatty mass in the FT
Lipomyelocele protrudes out from spinal cord. True/false
False
Terminal myelocystocele:
skin covered fluid filled lumbar mass protruding through a dysraphic defect
What is a terminal myelocystocele associated with?
omphalocele, bladder exstrophy and imperforated anus
decreased function of lower extremity (bowel + bladder)
What can be seen with terminal myelocystocele? What is it?
hydromelia– dilated central canal
