What is Acetylcholinesterase?
Breaks down acetylcholine into acetic acid and choline after synapse jump
How can Acetylcholinesterase be used in OB?
specific for detecting an open neuro tube defect
after 20 weeks it is perfered over AFP
What is the triple test?
15 weeks blood test used to detect Spina bifida, Trisomy 18 & 21
What will AFP be with a closed neuro tube defect?
What would the results of spina bifida be on a Triple Test?
What would the results of Trisomy 18 be on a Triple Test?
What would the results of Trisomy 21 be on a Triple Test?
What are the pros and cons of the triple test?
increases detection rates for trisomy 21 to 60% from 35% for AFP alone
high false positives
At what time is AFP not used?
after 20 weeks
What is the Quadruple test?
improvement of the Triple test with inhibin A added
What would the results of Trisomy 21 be on a quadruple Test?
Inhibin A increased.
What is PAPPA?
pregnancy associated plasma protein A
What happens to PAPPA during pregnancy?
PAPPA increases with increasing gestational age
What is PAPPA is low?
associated with anaploidy
What is anaploidy?
What is karyotyping?
isolating chromosomes and study them to look for anaploidy
How many chromosomes in each normal cell?
22 - mother
22 - father
What is Marfans Syndrome?
problems at chromosome 15
When does Marfans Syndrome present?
What are the symptoms of Marfans?
dissecting aortic aneurysm
mitral valve prolapse
What are Dominant disorders?
caused by a single defective gene
What are the chances of passing a dominant disorders on to a child?
What is achondroplasia?
dominant disorder of abnormal bone growth
normal intelligence and lifespan.
What is a recessive disorder?
caused by a pair of defective genes
What are the chances of passing a recessive disorders on to a child?
What are some autosomal recessive disorders?
What is Tay-Sachs?
fat collects in nerves.
What are x linked disorders?
passed from mothers to sons
What are some examples of x linked disorders?
Triple X females
What is klinefelter's Syndrome?
Male is born with extra X
What is typical syndrome of a prisoner?
What is Turner's syndrome?
child born with only 1 X sex chromosome.
What is a phenotype?
- interaction of one or more genes + enviroment
- how a gene is expressed
What is a mosaic?
gene mutation within cells
What is the amnio result of a mosaic?
mosaic is not a hermaphrodite
mosaic is not a hermaphrodite
hermaphrodite is always 46 XX
How many live births have chromosomal abnormalities?
Higher incidence of chromosomal abnormalities in ?
women over 36
elevated triple screen / quadruple screen
What is Trisomy 13?
What is Platau Syndrome?
Extra chromosome 13
fatal .... Most die in uteros
What is the Sonographic appearance of Platau Syndrome?
agenesis of corpus callosum
rocker bottom feet
congenital heart defects
What is holoprosencephaly?
1 brain hemisphere
look this up
What is rocker bottom feet?
rounded bottom (like rocker)
What is a genotype?
What is Trisomy 18?
What is Edwards Syndrome?
extra chromosome 18
fatal disease with a high risk of still birth
What is the average survival length of a baby with Edwards Syndrome after birth?
What is the sonographic appearance of Edwards Syndrome?
choroid plexus cysts
Agenesis of corpus callosum
congestive heart disease
2 vessel cord.
all triple test low
How often does Edwards Syndrome occur?
What is Trisomy 21?
What is down's syndrome?
an extra copy of chromosome 21
What is the sonographic appearance of Downs syndrome?
nuchal fold greater than 3
ceongenital heart disease
VSD, ASD, AVSD
What is Triploidy?
What if PAPPA is low?
associated with anaploidy
What is the common intrauterine findings of maternal derived triploidy?
What is a maternal derived triploidy ?
1 sperm (2 XX in egg)
What is a paternal derived triploidy?
1 egg - 2 sperm normally
spontaneous abortion or well grown baby
How common is the maternal derived compared to the paternal derived?
Maternal Triploidy - 10%
Paternal Triploidy - 90%
What is the common intrauterine findings of paternal derived triploidy?
multiple cystic spaces resembling a molar pregnancy
What is Turner Syndrome?
X linked syndrome where an X or Y chromosome is missing.
What is the the functional problem with Turner syndrome?
Pituitary fails to produce FSH so ovaries do not develop.
Females fail to produce estrogen and progesterone.
What is the path of female sex hormones?
- Thalamus releases GnRH to the pituitary
- FSH - control the menstrual cycle and the production of eggs by the ovaries
- LH - triggers ovulation and development of the corpus luteum
What is the most common finding in a fetus with Turner syndrome?
frequently with hydrops and cardiac defects
What are the possible anomalies associated with Turner syndrome?
What physical findings in a patient with turner syndrome?
immature sexual development
poorly developed breasts
widely spaced nipples
poor motor skills
The risk of Trisomy _________________ with age.
The risk of Trisomy increases with age.
What is the most common trisomy?
Trisomy 21 - downs syndrome
Trisomy 18 - Edwards syndrome
Trisomy 13 - Patau syndrome
What are the indications for a Level 2 ultrasound?
chromosomal abnormality detected
What is a teratogen?
an agent or factor that causes malformation of an embryo
What is the distinction between single vs multiple teratology?
any single abnormality increases the risk for multiple anomalies
What is the distinction between major vs minor teratology?
major requires surgical repair
minor anomalies interfere with normal function
About how many anomalies are found during ultrasound?
What is the occurrence of anomalies from teratogens depend on?
date of exposure
If a mother comes in contact with a teratogen during the pre-embryonic period (3-4 weeks) what is the most likely outcome?
If a mother comes in contact with a teratogen during the embryonic period (5-11 weeks) what is the most likely outcome?
major organ abnormalities
due to organogenesis
If a mother comes in contact with a teratogen during the fetal period (12+ weeks) what is the most likely outcome?
minor or tissue effects
What creates the amniotic fluid during early gestation?
What creates the amniotic fluid 5+ weeks gestation?
When does a fetus start to swallow?
8 - 11 weeks
When do the kidneys start to function?
When do kidneys produce majority of amniotic fluid?
When do kidneys produce almost all of amniotic fluid?
What is the function of the amniotic fluid?
allows fetal movement
prevents fetal adherence to amnion
allows for symmetric growth
What is necessary for normal lung development?
What problems can occur with the lungs with olighydramnios?
What is the AFI with olighydramnios?
- <5cm of fluid
What is the AFI with borderline olighydramnios?
- 5 cm to 8 cm
What is normal AFI?
8 cm to 22 cm
What is AFI with polyhydramnios?
> 22 cm
What can abnormal AFI be a marker for?
trisomy 13 - olig
What can cause polyhydramnios?
anything that interferes with swallowing & urination
- esophageal atresia
What happens to the AFI in the 3rd trimeter?
What is a normal 1 quadrant measurement for AFI?
2 - 8 cm
What are the features and complications of oligohydramnios?
- D: demise
- R: renal abnormalities (agenesis)
- I: IUGR
- P: premature rupture of membranes
- P: post dates
- C: chromosomal anomalies
What are the features and complications of polyhydramnios?
Disorders that decrease swallowing
- M: menigomyelocele
- O: omphalocele
- T: twin to twin
- H: hydrocephaly
- E: erythroblastoma
- R: retroperitoneal fibrosis
- S: sacrococcygeal teratoma
- H: hydrops fatalis
- O: obstructive GI anomalies
- U: urethral stenosis
- S: spina bifida
- E: esophageal atresia
What are 60% of polyhydramnios related to?
What is idiopathic?
What is Synechiae?
What are amniotic sheets?
insult to uterine lining
scar tissue in uterine lining
What is the danger of amniotic sheets
May cause early labor
When does the amnion join the chorion?
What is Amniotic band syndrome?
bands within the amniotic fluid adhere to the fetus and amputate portions of limbs..
What is the most severe form of amniotic band syndrome cause?
limb/body wall complex
What is limb/body wall complex called?
What is cyllosomia?
limb/body wall complex
cuts body in half
Cranial abnormalities are usually __________ to the fetus.
Cranial abnormalities are usually devastating to the fetus.
Where are the incidence of anencephaly higher?
What is the statistic of anencephaly between boys and girls?
What can prevent anencephaly?
4 mcg folic acid daily
Explain open vs closed neuro tube defect?
closed neurotube defects the brain and spinal cord are not in contact with the amniotic fluid
What will AFI be with a closed neuro tube defect?
How is a closed neuro tube defect seen?
What is anacephaly?
failure of closure of neurotube at cephalic end.
most common neuro tube defect
incompatible with life
What is the sonographic appearance of anacephaly?
absence of brain and cranial vault
What is encephaly?
variant of anencephaly in which some cortical brain remains
What is acrania?
absence of the cranial bones with the presence of complete (abnormal) development of brain
What can acrania appear as?
brain swells but can dissolve
What is Grober Syndrome?
What is a Cephalocele?
NTD in which the meninges or the meninges and brain herniate through the skull.
Where does cephalocele usually occur?
75% - occipital
What does prognosis of a cephalocele depend on?
What is an encephalocele?
cephalocele involving meninges and brain
What is a cranial meningocele
cephalocele involving meninges only
What is the sonographic appearance of a cephalocele?
What is spina bifida occult?
closed neuro tube defect
What is spina bifida cystica?
open neuro tube defect
What is spinal bifida?
2nd most common NTD
opening in the spine
What is the presentation of spina bifida?
cisterna magna gone
banana shaped cerebellum
lemon shaped head - none specific
V or U shaped splaying of spine
What is rachischisis?
failure of fusion of vertebral arches and neural tube with consequent exposure of neural tissue at the surface; spinabifida cystica with myelocele or myeloschisis.
What is Arnold Chari malformation?
cord tethering that pulls cerebellum into the upper cervical spine
What is the sonographic appearance of Arnold Chari malformation?
banana shaped cerebellum 99%
spina bifida cystica
What is Dandy Walker Malformation?
dilation of 4th ventricle
4 to 6 weeks gestation
What is the sonographic appearance of Dandy Walker Malformation?
enlarged cisterna magna (>10 alarming)
vermis of cerebellum abnormal
What is Dandy Walker Malformation associated with?
50 - 70% other abnormalities
What is holoprosencephaly?
intracranial anomaly in which a horse-shoe shaped ventricle replaces two lateral ventricles
What is holoprosencephaly associated with?
What is lobar holoprosencephaly?
What is semi-lobar holoprosencephaly?
What is alobar holoprosencephaly?
What is the sonographic appearance of lobar holoprosencephaly?
small channel of communication between lateral ventricles
What is the sonographic appearance of semi-lobar holoprosencephaly?
large channel of communication between lateral ventricles
What is the sonographic appearance of alobar holoprosencephaly?
1 lateral ventricle
How is a closed neuro tube defect seen?
What is the corpus callosum?
connecting nerve fibers
genu to slenum
When does corpus callosum develop?
12- 18 weeks
How many babies with ventriulomegaly will have normal intelligence?
What is ventriulomegaly?
marked dilation of the cerebral ventricles
What does ventriulomegaly imply?
* pay close attention to spine
What is ventriulomegaly usually accompanied with?
dangling choroid plexus
What is the most common cause of ventriulomegaly?
What is aqueductal stenosis?
a form of ventriulomegaly resulting in narrowing of the aqueduct of sylvius.
What is the sonographic appearance aqueductal stenosis?
symmetrical dilation of ventricles with intact fissure
dilated 3rd ventricle
What is a vein of Galen aneurysm?
large arteriovenous fistula seen as a sizeable cyst in the posterior aspect of the brain above the tentorium
What is the vein of galen?
drains lower mid portion of cranium
What is the sonographic appearance of vein of Galen aneurysm?
color lights up with turbulent flow
What is associated with a vein of Galen aneurysm?
congenital heart defect
What is hydranencephaly?
absense of cortical brain due to obstruction of ICA
no blood flow so brain does not develop.
What replaces brain tissue with hydrancephaly?
What causes hydrancephaly?
What is toxoplasmosis?
one of the world's most common parasite causing flu-like symptoms
What is cytomegalovirus?
a common virus that can infect almost anyone. Most people don't know they have CMV because it rarely causes symptoms
What is the sonographic appearance of hydrancephaly?
looks like big ass cyst
portions of midbrain and brain stem are present
What is microcephaly?
unduly small skull and brain
part of the brain herniates out of cranial cavity
What is microcephaly asscoiated with?
What is a teratoma?
congenital tumor caused by different types of tissue
What are the 3 types of tissues that teratomas grow from?
- germ cell layers
Where do teratomas usually occur?
around sacrum and coccyx
What is another name for nuchal fold?
nuchal fat pad
What is the measurement of the nuchal fold in babies with downs?
< 5 mm
What is a nuchal translucency?
is a finding during a specific period in the late first trimester and early second trimester (11.3-13.6 weeks) and should not be confused with nuchal thickness which is measured in the second trimester.
< 3 mm considered normal
What is a TORCH?
- virus that crosses placenta
- T: toxoplasmosis
- O: other
- R: rubella
- C: cytomegalovirus
- H: herpes
What is a porencephalic cyst?
cysts filled with CSF that communicates with the ventricular system
adjacent to ventricles
What is another name for porencephalic cyst?
What can cause porencephalic cysts?
What happens to the parenchyma with porencephaly?
undergoes necrosis and cystic lesion remains
What is Schizencephaly?
clefts in the cerebral cortex
What is the sonographic appearance of Schizencephaly?
fluid filled unilateral / bilateral clefts
What is Schizencephaly associated with?
absence of septum pellucidum and corpus callosum
What are arachnoid cysts?
fluid collection that occurs within the layers of the arachnoid layer
What is the sonographic appearance of arachnoid cysts?
rounded fluid collection in cranium
What is arachnoid cysts associated with?
agenesis of the corpus callosum
What is a choroid plexus cyst?
cyst within the lateral ventricles
What can a choroid plexus cyst be associated with?
trisomy 18 (edwards)