Anomalies in Polyhydramnios 1 Flashcards
Polyhydramnios
High amount of amniotic fluid
Poly measurement for AFI
> 24 cm
Poly measurement for SDP
> 8 cm
Agenesis of the corpus callosum
cerebral hemispheres do not connect
Characteristics associated with agenesis of the corpus callosum
elevation of the 3rd ventricle, tear drop sign (dilatation of the occipital horns), absence of CSP, steer sign (outward angling of the frontal horns)
Acrania is also called?
Exencephaly
Exencephaly
Absence of calvarium; has brain tissue
Characteristics of exencephaly
Normal facial bones, lack of echogenic bony calvaria, single brain mass protruding from head
What is the most common neural tube defect?
Anencephaly
Anencephaly
Cephalic end of neural tube does not completely close; absence of brain tissue
Anencephaly has an increase in what lab value?
AFP
Characteristics of anencephaly
bulging eyes (frog face), increase in fetal activity
Characteristics of iniencephaly
defect of occipital bone (posterior encephalocele), spina bifida of C spine, stargazing sign (retroflexion of the head)
Encephalocele
protrusion of brain through defect in skull covered by membrane
In which region of the head are encephaloeceles more common?
occipital
True or False: An encephalocele has elevated AFP
False; contained in membrane
Characteristics of Arnold-Chiari Malformation
Spina bifida aperta, lemon shaped skull, banana-shaped cerebellum (obliterated CM), ventriculomegaly
A lemon-shaped skull is only found with?
Arnold-Chiari Malformation
Type I Arnold-Chiari Malformation
without meningocele
Type II Arnold-Chiari Malformation
with meningocele
Dandy-Walker Malformation
Malformation of the cerebellum
Characteristics of Dandy-Walker Malformation
enlarged posterior fossa, splaying of cerebellar hemispheres, complete or partial agenesis of vermis
An enlarged posterior fossa is also called a?
posterior fossa cyst
A missing vermis is only seen with?
Dandy-Walker Malformation
Holoprosencephaly
disorder from abnormal development of prosencephalon (forebrain)
What is the most severe form of holoprosencephaly
Alobar
Characteristics of alobar holoprosencephaly
horseshoe ventricle (monoventricle), fused thalami,
Characteristics of holoprosencephaly
hypotelorism (cyclopia if severe), proboscis-like nose, arrhinia (absent nose)
Hydraencephaly
Brain tissue is replaced by CSF
TORCHS can cause?
hydraencephaly, porencephaly, schizencephaly, arachnoid cyst
Characteristics of hydraencephaly
anechoic head with midline falx
What does TORCHS stand for?
toxoplasmosis, rubella, cytomegalovirus, herpes simplex, syphilis, parvovirus
Porencephaly
unilateral or bilateral cystic defects in brain
Characteristics of porencephaly
cystic areas that can communicate with ventricles
Schizencephaly
clefts in cerebral cortex
Characteristics of schizencephaly
fluid filled open or closed clefts, absence of CSP and corpus callosum
Arachnoid cyst
congenital abnormality of the pia-arachnoid layer
Characteristics of an arachnoid cyst
midline, fluid filled cyst, cannot communicate with ventricular system
Choroid plexus cyst
unilateral or bilateral cysts within choroid plexus due to folds
True or False: A choroid plexus cyst has a poor prognosis
False; good prognosis
Vein of Galen aneurysm
not a true aneurysm, arteriovenous malformation, dilated internal cerebral vein
Characteristics of a VGAM
round, fluid filled structure at midline, lights up with color
True or False: Cervical teratomas are usually benign
True
Where are cervical teratomas most common?
anterolateral neck region
Why is a cervical teratomas associated with polyhydramnios?
mass compresses with esophagus and interferes with fetal swallowing
Hydrocephalus
Increase in ventricular volume of CSF; ventriculomegaly
Characteristics of hydrocephalus
frontal bossing, dilated lateral ventricles (>10mm), bell clapper sign (dangling of choroid plexus)
Spina bifida
Failure of the neural tube to close completely
Characteristics of spina bifida occulta
defect is covered by soft tissue; normal AFP
Characteristics of spina bifida aperta
defect is uncovered, high AFP
In which plane is splaying of the spine best seen?
Transverse
Rachischisis
complete spina bifida; entire spine is affected
On which portion of the spine is spina bifida most common?
lumbar
Myelomeningocele
Herniation of vertebral column where sac contains spinal cord, meninges, CSF
Meningocele
Herniation of vertebral column where sac contains meninges and CSF only
What is the most common tumor found in newborns?
sacrococcygeal teratoma
True or False: Sacrococcygeal teratomas are usually malignant
False; usually benign
What is the difference in location of a meningocele and a sacrococcygeal carcinoma?
Meningocele is usually on lumbar spine which a sacrococcygeal carcinoma is more towards the sacrum and coccyx (baby’s butt)
Epignathus
benign tumor that originates in the palate/pharynx and grows into the mouth
Types of facial cleft
unilateral, bilateral, median
Characteristics of facial cleft
perpetually open mouth, break in lip
Hypotelorism
Eyes are abnormally close together
What is the normal distance between orbits?
one orbit
Hypoterlorism is associated with?
Holoprosencephaly
Hypertelorism
Eyes are abnormally far apart
What is hypertelorism related to?
craniosynostosis and anterior cephaloceles
Microphtalmos
reduction in the size of the orbit
Cyclops
AKA synophthalmia, orbits fuse into one singular orbit
Cyclops is associated with?
holoprosencephaly
Macroglossia
hypertrophy of the tongue
Micrognathia
small mandible; small chin with overbite