URR- ANOMALIES OF THE FETAL SKULL & FACE

acrania

1. AKA exencephaly 2. lack of cranial bone formation 3. cerebral tissues form but in abnormal way 4. identified as early as 12 weeks 5. increased AFP (neural tube defect)

fetal goiter

1. anterior neck mass 2. result = tracheal compression postnatal respiratory issues 3. cause = by maternal conditions or fetal hypothyroidism 4. PUBS can be performed to assess fetal thyroid status

cystic hygroma (CH)

1. collection of lymphatic fluid from obstruction 2. occurs on posterior neck (80%) 3. strongly associated with chromosomal abnormalities affecting AFP levels, polyhydraminos, hydrops, pleural effusion, ascited & anasarca 4. appears similar to encephalocele, cystic teratoma, meningomyocele 5. differentiated from encephalocele by evaluating cranial structure for presence of opening

encephalocele sonographic appearance

1. complex cystic mass connected to cranium 2. abnormal appearance of intracranial structures

teratoma

1. composed of ectodermal tissues 2. forms in many locations- usually along midline of body 3. pharynx, neck, sacrum, brain & skull sutures

hypotelorism

1. decreased distance b/w eyes 2. best evaluated for measurement in axial view of head 3. interocular distace below 5th percentile 4. commonly seen with holoprosenencephaly/median cleft face 5. associated with fetal alcohol syndrome/microcephaly

coronal plane facial evaluation

1. demonstrates nose & upper lips 2. evaluate lens of both eyes

dolichocephaly

1. elongated OFD 2. long, narrow head 3. associated with craniosynostosis, breech presentation & oligohydraminos

axial plane facial evaluation

1. evaluate orbits & eyes, superior lip & palate 2. mandible should demonstrate contiguous "U" shape 3. maxilla should demonstrate contiguous "V" shape

sagittal plane facial evaluation

1. fetal profile assessment 2. possible deformation of forehead or nose 3. measure philtrum (vertical groove in upper lip) 4. evaluate nasal bone, facial angle, chin/jaw positioning 5. confirm mandible & maxilla aligned at their midpoints

cyclopia

1. formation of single ocular cavity 2. located along midline of face 3. associated with other midline facial & cranial defects

meningocele

1. herniation of meninges ONLY through opening in skull 2. cystic structure seen in posterior aspect of skull 3. increased MSAFP

fetal goiter sonographic appearance

1. homogeneous 2. central neck mass 3. well-defined borders

cebocephaly

1. hypotelorism & a nose with single nostril 2. associated with holoprosencephaly

ethmocephaly

1. hypotelorism with no nose 2. only a proboscis present 3. associated with holoprosencephaly

macrocephaly

1. increase fetal head size 2. HC = over 98th percentile for age 3. BPD & HC = 2 or more standard deviations above average for gestational age 4. associated with hydrocephalus, hydranencephaly, beckwith wiedemann syndrome

hypertelorism

1. increased distance b/w eyes 2. best evaluated for measurement in axial view of head 3. interocular distance = above 95th percentile 4. associated with cephalocele, craniosynostosis, trisomy 21, frontonasal dysplasia, meningoencephalocele, noonan syndrome, trisomy 13, turner syndrome

cystic hygroma identified in 1st trimester

1. indicates trisomy 21 2. low MSAFP

cystic hygroma identified in 2nd trimester

1. indicates turner syndrome 2. low MSAFP

encephalocele

1. meninges & brain tissue herniation through bony defect in calvarium (skullcap) 2. most in posterior/occipital location 3. leads to CSF obstruction of flow 4. poor prognosis 5. can be part of meckel gruber syndrome 6. can be part of pentalogy of cantrell

absent nasal bone

1. midsagittal plane 2. identify tip of nose & angle the beam until perpendicular to nasal bone to improve reflection 3. normal nasal bone appears like equal sign from skin layer being echogenic similar to bone 4. associated with trisomy 21

anencephaly

1. most common NTD 2. absence of upper cranial vault & cerebral tissue 3. eyes = present but exophthalmos present (frog eyes) 4. seen as early as 12 weeks 5. seen with other spinal defects & polyhydraminos 6. increased AFP

cleft lip/palate

1. most common facial defect- more common in males 2. most common type = unilateral cleft lip with cleft palate 3. medial cleft seen with congenital anomalies 4. midline or median cleft lip associated with other midline cranial defects like holoprosencephaly 5. assymmetric facial clefts associated with amniotic band syndrome 6. best evaluated @ 20 weeks evaluated in coronal views & extent of condition evaluated in axial planes 7. seen on u/s as anechoic space extending from nostrils through the lip 8. associated with polyhydraminos, flattened nostrils, hypertelorism 9. isolated cleft palate commonly associated with Pierre robin sequence

cystic hygroma occurring as an isolated abnormality

1. no change in MSAFP levels 2. can be surgically removed with good prognosis

lemon shaped skull

1. normal 2. open neural tube defects 3. chiari II malformation

epignathus

1. pharynx teratoma 2. grows out of mouth 3. may cause neck to become hyperextended

ear creases

1. pits or creases in lob & skin near ear 2. associated with beckwith-wiedemann syndrome

low-set ears

1. positioned 2 or more standard deviations from normal 2. associated with trisomy 13, 18 & 21

craniosynostosis

1. premature ossification of 1 or more skull sutures 2. causes abnormally shaped calvarium & abnormal facial features 3. restricts cerebral growth/development 4. associated with thanatophoric dysplasia, apert, crouzon & pfeiffer syndromes 5. demonstrated as abnormal irregular skull shape in transverse axial view 6. presents as clover leaf skull/strawberry skull

frontal bossing

1. prominent forehead with absent/hypoplastic nasal bone 2. commonly seen with trisomy 21

brachycephaly

1. shortened OFD 2. very round head 3. associated with trisomy 21, 18 & craniosynostosis

microtia

1. small ear 2. strong association with trisomy 21

microcephaly

1. small fetal head for GA 2. HC below normal by > 2 standard deviations 3. associated with porencephaly, lissencephaly, holoprosencephaly, maternal phenylketonuria, fetal alcohol syndrome & intrauterine infections 4. seen with hypotelorism, trisomy 13, 18 & meckel gruber syndrome

wormian bones

1. small ossification centers within cranial sutures 2. associated with trisomy 21, cleidocranial dysplasia, osteogenesis imperfecta

proboscis

1. soft tissue mass protruding from anterior/superior face 2. seen with arhinia & orbital abnormalities 3. associated with holoprosencephaly

cystic hygroma sonographic appearance

1. thin walled complex mass with septations 2. normally extends posteriorly from neck

micrognathia

1. undersized jaw 2. best seen in sagittal plane 3. associated with absent mandibular gap 4. can correct itself with growth & teeth formation 5. seen with polyhydraminos from dysphagia (70%), trisomy 18 & pierre robin syndrome 6. associated with increased risk of acute neonatal respiratory distress 7. tongue can obstruct airway during delivery

macroglossia

1. unusually enlarged tongue extending beyond teeth or alveolar ridge 2. related to amyloidosis, hypothyroidism, overgrowth/chromosomal disorders 3. leads to fetal dysphagia & polyhydraminos 4. seen with beckwith-wiedemann syndrome, trisomy 21, triploidy

fetal cataracts

1. vitreous(fluid) & lens of eye normally hypoechoic & lens outline/orbit wall are hyperechoic 2. best evaluated in coronal view demonstrating lens of eye 3. cataract formation causes echogenic lens with central clouding or complete opacity

anotia

absence of external ear

cloverleaf shaped skull

associated with thanatophoric dysplasia

strawberry shaped skull

associated with trisomy 18

agnathia

complete or partial absence of jaw

normal ossification of cranium

ossified by 15 weeks & easily visualized

retrognathia

posteriorly displaced jaw