Topic 8 - fetal spine and msk

Question 1

What are the most common spinal pathology?

Answer 1

Spina bifida
Scoliosis and kyphosis
Sacral agenesis
Tethered cord

Question 2

What are the sonographic signs of spina bifida in the head?

Answer 2

anencephaly
exancephaly
intracranial translucency
aqueduct of sylvius
posterior brainstem
chiari II malformation
concave deformity of the frontal bone (lemon head)

Question 3

What are some sonographic signs of spina bifida in the lumbar spine?

Answer 3

Associated cranial malformations
Laminae fail to converge towards the midline
Increased interpedicular distance
Pedicles may diverge away from the midline instead of being parallel
Absent overlying skin or subcutaneous tissue

Question 4

How do you interpret the BSOB measurement?

Answer 4

the brain stem diameter is always smaller than the brain stem to occipital bone (BSOB) diameter in normal fetuses and the opposite is true in fetuses with open spina bifida (OSB)

Question 5

How do you interpret intracranial transluceny as a marker for spina bifida?

Answer 5

At 11–13 weeks’ gestation the fourth cerebral ventricle is easily recognizable as an intracranial translucency in the standard mid-sagittal view of the face used routinely in screening for chromosomal abnormalities. In some cases of open spina bifida the fourth ventricle is not visible

Question 6

What is pathological kyphosis and scoliosis associated with?

Answer 6

often associated with spina bifida or ventral abdominal wall defects

Question 7

What is sirenomelia?

Answer 7

Absence of sacrum
Fusion of legs
Abnormal or absent foot structures
Lethal condition associated with severe oligohydramnios due to renal abnormalities