Neural tube/musculoskeletal with pathology registry review Flashcards
Neural tube defects
Neural tube fails to close or form properly
Risk factors for NTD
Maternal diabetes, valproic acid (seizure meds), folate deficiency
Folic acid
Supplement taken to reduce risk of anencephaly and spina bifida
Marker for open defects
Elevated AFP
Acrania
Absence of cranial vault above the orbits. Can be with or without brain. “Without cranium”
*elevated AFP
Anencephaly
No cerebral hemispheres, frog like bulging eyes
Exencephaly
Normal amount of brain tissue/no skull. Will appear as misshapen head with no hyperechoic bone surrounding head.
Spina bifida
Neural tube fails to close and there is a gap between the vertebrae/splaying of the vertebral laminae.
*aka spinal dysraphism/meningocele/myelomeningocele
Spina bifida occulta
CLOSED
Covered by skin and no herniation of spinal cord outside of body, defect in vertebrae only
*normal AFP
Postnatal signs for spina bifida occulta
Sacral dimple, lipoma, excessive hair
Spina bifida aperta
OPEN
-Most common form of spina bifida
-Not covered by skin and result in herniation of spinal contents (cystica)
*ELEVATED AFP, strongly associated with Arnold-Chiari II malformation
Meningoceles
Contain meninges only
*cystic appearance
Myelomeningocele
Contains meninges and nerve roots, more complex in appearance. Most commonly in lumbosacral area
*MOST common
Arnold-Chiari II malformation
-Presence of open spina bifida
-Meningocele or myelomeningocele pulls down on spinal contents causing cranial malformations
-Lemon shaped head
-Banana cerebellum
-Obliterated cisterna magna
Cephalocele/Encephalocele
-Herniation of intracranial contents through opening in skull
-Most common in occipital location
-Associated with Meckel-Gruber (occipital cephalocele and PKD)
*ABNORMAL AFP
Iniencephaly
Hyperextension of neck. Closed NTD
“star gazer”
*Possible normal AFP
Ocular diameter
Lateral to medial edge of orbit
*Axial plane
Interocular
Between the 2 eyes. Medial (inner) sides of both
Binocular
Lateral edged of both orbits, both eyes
Anopthalmia
No orbits
*associated with T13
Cyclopia
One fused eye
*associated with T13
Hypertelorism
Closely spaced eyes (decreased interocular)
*associated T13
Hypertelorism
Far apart (increased interocular) anterior cephalocele
Micropthalmia
Small orbits (decreased ocular)
Proboscis
False nose/projection replacing or above nose
*often seen with eye abnormalities
Cleft lip and palate
Abnormal/incomplete closure of lip and/or palate
-Can be unilateral, bilateral, midline or eccentric
-May be isolated or associated with holoprosencephaly and T13(midline), and amniotic band syndrome (asymmetrical)
-Evaluated in coronal view of lips, nose, chin
Nuchal thickening
> or equal to 6mm measurement of nuchal fold between 18-23 weeks
*trisomy 21
Flattened or absent nasal bone
May be normal in some individuals based on ethnicity
-ML sagittal view
*“soft marker” for trisomy 21