Test 3 Flashcards
(223 cards)
1
Q
conceptual age is same as
A
embryologic age
2
Q
conceptual/embryologic age counts from
A
first day of conception
3
Q
gestational age is same as
A
menstrual age
4
Q
gestational age starts counting from
A
1st day of LMP
5
Q
what “age” is used to date pregnancy
A
gestational age
6
Q
why are 1st trimester US not normally performed
A
Insonation
may not see embryo yet
can’t help embryo before 12 weeks
7
Q
what is embryo initially sustained by
A
yolk sac and ovary
8
Q
at what point is it a zygote
A
conception - 12 days
9
Q
at what point is it an embryo
A
implantation to 10 weeks
10
Q
at what point is it a fetus
A
10 weeks or more
11
Q
when does the heart reach adult configuration
A
8 weeks
12
Q
when does normal gut herniation occur and when it is abnormal
A
9.5-12.5 weeks
abnormal if not by 14 weeks
13
Q
equation for gestational age
A
conceptual age + 2 weeks (14 days)
14
Q
when does fertilization occur
A
1-2 days after ovulation
15
Q
what determines sex of the baby
A
sperm
16
Q
what is a proper location for implantation
A
uterine fundus
17
Q
what does blastocyst contain
A
trophoblastic cells and “inner cell mass” forming embryo
18
Q
what stimulates maternal pregnancy responses
A
trophoblastic cells secreting hCG
19
Q
what does hCG from trophoblastic cells do
A
causes endometrium to convert to decidua
20
Q
what is the purpose of decidua
A
nourish early pregnancy
21
Q
when does blastocyst enter the uterus
A
4-5 days post fertilization
22
Q
when does implantation occur?
A
12 days post ovulation
23
Q
what allows implantation to occur
A
proteolytic enzymes produced by trophoblasts
24
Q
what are lacunae
A
blood pools created by erosion of maternal capillaries to nourish trophoblastic cells
25
what is placenta and fetal/maternal circulation made out of
lacunae
26
what does inner cell mass mature into in a consepsus
bilaminar embryonic disk (embryo and promary yolk sac)
27
when is primary yolk sac pinched off
23 days GA
28
how is primary yolk sac pinched off
by entra embryonic celom
29
when is secondary yolk sac seen
1st trimester
30
when are amniotic and chorionic cavities seen
1st trimester
31
location of chorion and amnion
chorion is outer
amnion is inner
fused when placenta forms
32
how much does embryo grow
1mm/day
33
when are major internal/external structures developed
week 4-10 (embryonic phase)
34
when does initial heartbeat occur
5.5-6 weeks
35
what is normal CRL by end of 10th week
35mm
36
when is beginning of fetal period
last 2 weeks of 1st trimester
| weeks 11 and 12
37
what is normal fetal head size at the end of 1st trimester
half of CRL
38
when is fetal anatomy fully developed?
late frist trimester
39
what is the goal of sonography in late first trimester
anomaly detection
40
what improves diagnosis of IUP or ectopic
US and hCG levels
41
normal gestational sac hCG SIS on TAS
>1800 mIU/ml
42
normal gestational sac hCG SIS on TVS
>500 mIU/ml
43
hCG level of ectopic pregnancies
lower than normal
44
normal IUP hCG increase in
2x every 2 days
45
what happens to hCG before spontaneous nonviable expulsion
they fall
46
when do hCG levels plateau/decline
9-10 weeks
47
what should you suspect if hCG plateau's later than 9-10 weeks
trisomy 21
48
screening marker for Down's and when it's performed
hCG levels in 1st and 2nd trimester
49
PAPP-A
produced by trophoblastic (placental cells)
Bone and tissue formation
increases with advancing gestation
50
PAPP-A in Downs
lower initially
| NOT USEFUL IN 2ND TRIMESTER
51
Strogenst biochemical marker for Downs at 9-11 weeks
PAPP-A
52
components of 1st trimester eval (5)
1. locate gestational sac (scan uterus and adnexa)
2. measure embryo and/or sac
3. m-mode for cardiac activity
4. fetal number and chorionicity
5. evaluation of uterus, adnexa and cul-de-sac
53
when can you see embryo on TVS
5.5 weeks
54
appearance of IUP at 5 weeks on TVS
1-2mm sac (echogenic ring, sonolucent center representing chorionic cavity)
55
portion on myometrial/burrowing side
decidua basalis
56
villi covering ebryo
decidua capsularis
57
normal features of gestational sac (5)
1. round/oval
2. fundal location
3. eccentrically placed
4. smooth contours
5. DDS wall thickness >3mm
58
implantation in lower uterine segment is associates with _____ and ____
placenta accreta and placenta previa
59
When is yolk sac seen?
MSD >12mm
60
When is embryo seen? (MSD measurement and GA)
MSD >18mm
| 5.5-6 weeks
61
how fast does gestational sac grow?
1mm/day
62
when does embryonic heart motion begin?
5.5 weeks
63
what is a good landmark to image embryo in early pregnancy
yolk sac
64
functions of yolk sac (3)
1. provide nutrients
2. hematopoiesis
3. development of endoderm (forming primitive gut)
65
when does yolk sac detaches from yolk stalk (and embryo)
8 weeks
66
failure to visualize yolk sac with min ______mm MSD on TVS is abnormal
12
67
yolk sac should be seen within MSD of _______ and always be seen with MSD _____
10-15mm
| 20mm
68
Growth rate of yolk sac compared to MSD
0.1mm/ml MSD
69
normal diameter of yolk sac should be less than _____
6mm
70
chorion and amnion fuse at how many weeks GA
12
71
what is it called when bilaminar disk becomes trilaminar
gastrulation
72
when does gastrulation occur
5th week GA
73
When does organogenesis begin
5th week
74
CRL at 5.5 weeks
3mm
75
heart beat should be seen by the time CRL is ______
>4mm
76
when does embryonic curling begin?
6.2 weeks
77
where are the dumping grounds for embryonic waste
chorionic cavity and placenta later
78
when does fusion of chorionic and embryonic cavities occur
14-15 weeks
79
when does trilaminar disk fold into c shape and what is it called
6th week
| curling
80
what is yolk stalk made out of
head, caudal portions and lateral folds
81
what becomes of dorsal aspect of yolk sac
foregut, midgut, hindgut, GI tract, liver, biliary tract and pancreas
82
what is umbilical cord made out of
yolk stalk connecting stalk and allantios
83
what does spine develop from and when does it close
ectoderm to neural tube. Closes at 6th week GA
84
whats visualized at 7 weeks in cranium?
| 8 weeks?
single vesicle
| 3 vesicles
85
Rhombencephalon divides into which 2 cavities and forms ______
cephalic - metencephalon
caudal - myelencephalon
forming cystic rhomboid fossa
86
when does midline falx form
9 weeks GA
87
when is cerebellum fused
10 weeks
88
when are brain structures complete
shortly after 10 weeks
89
when do limb buds develop
6th and 7th week
90
when are hands and feet completely formed
10 weeks
91
when are limbs identified and why
10 weeks because you can see calcifications of long bones
92
when does calcification of clavicle begin?
8 weeks
93
when are frontal and cranial bones occified
9 weeks
94
anterior abdominal wall developed by _____
6 weeks
95
anterior abdominal wall forms from:
fusion of four ectomesodermal body folds
96
primitive gut is formed :
6 weeks. when dorsal yolk sac incorporates into embryo
97
midgut forms _____
small bowel, cecum, ascending colon, proximal transverse colon
98
how is yolk stalk formed
when amniotic cavity expansion pulls yolk sac away from embryo
99
when does midgut loop return to fetal abdomen
11th week
100
echogenic mass within the umbilical cord is most likely ____
normal bowel herniation
101
what can bowel herniation be confused with
omphalocele or gastroschisis
102
first organ to function in an embryo
heart
103
start of fetal heart beat (weeks and days)
5-5.5 weeks
| 35 days
104
cardiac activity should always be seen by _______ or ______ CRL
46 days GA
| >4mm CRL
105
fetal heart rates
90-115 bpm at 6 weeks
140-160 bpm at 9 weeks
140 bpm through remainder of 1st and 2nd trimester
106
heartbeat of _____bpm provides discrimination for maternal heartbeat
100 bpm
107
determination of GA is done by (2)
CRL and gestational sac size
108
gestational sac size is accurate until
8 weeks
109
When measuring MSD, where should the calipers be placed
inner to inner
110
equation for menstrual age
MSD + 30 (in days)
| menstrual age / 7 = in weeks
111
most accurate dating parameter in obstetrics first 12 weeks GA
CRL
112
why is CRL not accurate after 12 weeks
due to curling of fetus
113
what does the triple screen test measure
AFP, hCG, Estiol
114
Measurements/Procedures of 1st trimester risk assessment (4)
amniocenthesis
triple screen
chorionic villi sampling
NT measurement
115
in what plane should NT measurement be taken
midsagittal with head in neutral position
116
down syndrome phenotype
small nose and mid-face hypoplasia
117
twin gestations have ______ times greater mortality rate
7-10
118
increased risk for twin mortality when _______ (2)
they're monozygotic and share membrane components
119
early sign of twin to twin transfusion syndrome
difference in NT measurements
120
which type of twin pregnancy is most common
dichorionic/diamniotic
| dizygotic
121
presentation of dichorionic and diamniotic pregnancy
| 4
two separate sacs
thick dividing membrane
fraternal
twin peak sign
122
monochorionic diamniotic twins (MCDA) (4)
single gestational sac
2 amnions
2 yolk saks
2 embryos
123
how does MCDA pregnancy occur
separation of single zygote in blastocyst phase
124
Monochorionic Monoabnionic pregnancy presentation (5)
```
1 sac
1 yolk sac
1 amniotic membrane
2 embryos
must deliver early to prevent entanglement
```
125
when can cystic rhomboid fossa be seen sonographically
8-11 weeks
126
when are cerebral hemispheres seen
9 weeks
127
when is choroid plexus seen
9 weeks
128
goal of sonography is 1st trimester (6)
1. visualization of gestational sac (IUP or ectopic)
2. embryonic demise or living
3. high risk monitoring
4. number of embryos, chorionicity and amnionicity
5. gestational dating
6. diagnosis of fetal anomalies
129
what percentage of pregnancies are miscarried?
15%
130
most common presentation for pregnancy complications
vaginal bleeding
131
when pregnant lady has vaginal bleeding, what should you investigate (4)
embryo, heart beat, yolk sac, RPOC
132
another name for placenta
frondosum
133
what does detachment of placenta result in
hematoma and vaginal bleeding
134
hemorrhage contiguous with placental edge is most likely ______
placental hematoma
135
placental hematoma can be caused by
trauma or MVA
136
why do placental hematomas "not" cause bleeding
because they're within the chorion and no communication with endo
137
most common cause of 1st trimester bleeding
subchorionic hemorrhage
138
hemorrhage found between myometrium and gestational sac
subchorionic
139
hemorrhage between placenta and uterus
subchorionic
140
lucency posterior to placenta is most likely from
abruptio placentae
141
T or F:
| subchorionic hemorrhage is avascular
true
142
where is the bleed seen in subchorionic hemorrhage
adjacent to gestational sac
143
characteristics of absent intrauterine sac (3)
empty uterus
absence of adnexal masses or free fluid
positive hCG levels
144
how fast doe the embryo grow during 1st tri
1mm/day
145
differentials for abnormally thick endo (4)
intrauterine blood
RPOC
decidual reaction with ectopic
decidual changes from early pregnancy
146
incomplete abortion sono findings (2)
intact sac with nonviable embryo
| collapsed or misshapen sac
147
sono signs of RPOC (4)
endo >8mm
increased vascularization of endo
color Doppler strongly positive
obvious fetal parts
148
what can RPOC be mistaken for
blood clots
149
conditions associated with empty gestational sac (3)
normal IUP
150
gest sac is seen TA ad TV when MSD is _____ and GA is _______
5mm
| 4-5 weeks
151
GA growth rate
1mm/day
152
GA at which SAB can be made
6.4 weeks
153
hCG in anembryonic pregnancy
rise but not at a rapid rate
154
appearance of anembryonic pregnancy
large
| empty gest sac
155
MSD growth rate ____
| abnormal if ____
1.13mm/day
156
trophoblastic reaction in ABNORMAL IUP (4)
irregular
absent DDSS
trophoblastic reaction
157
clinical hallmark of gestational trophoblastic disease (5)
1. vaginal bleeding in 1st and early 2nd trimester
elevated hCG (>100k)
hyperemesis gravidarum (N/V, weight loss, dehydration)
preeclampsia (HTN and proteinuria)
AFP low
158
US presentation of a mole (10)
```
distorted sac
thin, weakly echogenic or irregular choriodecidual reation
absence of DDSS
MSD >10mm
snowstorm
cluster of grapes
bilateral adnexal fullness
theca lutein cysts
uterus larger than date
```
echogenic soft tissue with cystic spaces representing hydropic chorionic villi
159
molar pregnancy may simulate (4)
missed abortion
incomplete abortion
blighted ovum
hydropic degeneration of placenta
160
malignant forms of trophoblastic disease (2)
invasive mole
| choriocarcinoma
161
where does choriocarcinoma metastasize to? (3)
liver, lungs, brain
162
vaginal bleeding, dyspnea, abdominal pain and neurologic symptoms are consistent with
choriocarcinoma
163
when is heart tube formed
3.5-5weeks
164
when do yolk sac and gestational sac diverge
after 7 weeks
165
embryonic heart rates of _____ are abnormal
170
166
heart rate of >170bpm may lead to (2)
heart failure and hydrops
167
expected YS growth
.3mm/day
168
side by side appearance of amnion and yolk sac is seen between ____ and ____ week and is known as ______
5-7the week
| double bleb sign
169
mean amniotic sac diameter should be __________
equal to CRL
170
risk factors of ectopic (5)
```
PID
IUD
fallopian tube surgeries
infertility treatment
history of ectopic pregnancies
```
171
clinical findings in ectopic (4)
vaginal bleeding
empty uterus
adnexal mass
positive pregnancy test
172
sites of ectopic pregnancy (6)
```
fallopian tube
ovary
broad ligament
peritoneum
cervix
cornua
```
173
which ectopic location is the most dangeour
interstitial fallopian tube near cornu
174
how many percent of patients with ectopic pregnancy have pseudogestational sac
20
175
what is the difference between pseudogestational sac and normal gestational sac
pseudo - no embryo or YS
centrally located
gestational sac - all pregnancy parts and ESSENTRICALLY placed
176
how many live ectopic pregnancies are identified on TA
10%
177
most frequent finding with ectopic pregnancy
most specific finding in ectopic pregnancy
extrauterine sag
live embryo
178
presentation of extrauterine gestational sac
thickened echogenic ring (representing trophoblastic tissue or chorionic villi)
separate from ovary
179
doppler RI in ectopic pregnancy
180
complex adnexal mass differential for ectopic
peritoneal hematoma
| hematosalpinx
181
when you see fluid in the cul-de-sac, where else should you look and why
gutters, RUQ and LUQ
to see extent/volume
182
why is interstitial/cornual pregnancy most life threatening
b/c of parauterine and myometrial vasculature causing life-threatening hemorrhage
183
ectopic pregnancy with increased risk of hysterectomy
cervical
184
nuchal translucency definition
max thickness of subcutaneous lucency at back of neck between 11 and 14 weeks GA
185
what does thickened NT hint
genetic syndromes
186
age and size requirements for NT measurements
11 weeks to 13 weeks 6 days
| 45mm to 84mm
187
first trimester evaluation can be done for what anomalies? (5)
```
NT
presence/absence of nasal bone
tricuspid regurg
abnormal flow in ductus venosus
abnormalities of hind brain
```
188
when are 4 chamber heart and great vessels seen
12 weeks
189
markers for cardiac defects (5)
increased NT
tricuspid regurg
reversal/absence of flow in ductus venosus
ectopia cordis and limb body wall complex
190
when is embryonic head identified
7 weeks
191
dominant structure seen in cranium at 1st trimester
choroid plexus
192
acrania
partial or complete absence of cranium
193
what is acrania predecessor for
anencephaly
194
sign associated with acrania
mickey mouse head
195
anencephaly
absence of brain and cranial vault
cerebral hemispheres are missing or small
base of skull may be preserved
196
cephalocele
midline cranial defect with herniation of brain and meninges
197
iniencephaly
defect occiput involving foramen magnum
retroflexion of spine (occipital cranium directed toward lumbar spine)
open spinal defect
198
ventriculomegaly
dilation of ventricular system without cranial enlargement
199
when does ventriculomegaly occur
after 11 weeks
200
how does ventriculomegaly appear
enlarged ventricles
| compression and thinning of chorioid plexus "dangling" in lateral ventricle
201
holoprosencephaly
complete to partial failure of cleavage of prosencephalon with facial dysmorphism
prosencephalon does not differentiate into cerebral hemispheres and lateral ventricles
202
what are three types of holoprosencephaly
alobar
semilobar
lobar
203
which type of holoprosencephaly is the worst and how does it present (6)
alobar
single ventricle, small cerebrum, fused thalami, agenesis of corpus callosum and falx cerebri
204
dandy-walker malformation
dilation of 4th ventricle
| dysgenesis or agenesis or cerebellar vermis
205
when does dandy-walker occur
6-7 weeks GA
206
US presentation of dandy walker (3)
posterior fossa cyst continuous with 4th ventricle
absent cerebellum
dilated 3rd and lateral ventricles
207
Spina bifida
failure of neural tube to close after 6 weeks
208
appearance of spina bifida
spinal irregularities or bulging within posterior contour
| extrusion of mass from vertebral column
209
clinical signs of spina bifida (2)
```
lemon sign (scalloping of frontal bones)
banana sign (curved appearance of cerebellum)
```
210
normal abdominal herniation measurements
6-9mm at week 8
| 5-6mm at week 9
211
at what measurement should gut herniation be considered abnormal
>6mm
212
when is urinary bladder normally seen
10-12 weeks
213
what causes large urinary bladder
obstructive uropathy (especially at the level of urethra)
214
one of the most common abnormalities seen on US in 1st tri
cystic hygroma
215
what is cystic hydroma associated with
trisomies (turner's)
216
where is cystic hygroma visualized
posterior next and upper thorax
217
what measurement of neck thickening is abnormal
>3mm
218
differential considerations for umbilical cord cysts (6)
```
amniotic inclusion cysts
omphalomesenteric duct cyst
allantoic cysts
vascular anomalies
neoplasms
wharton's jelly abnormalities
```
219
most common ovarian mass in 1st tri
corpus luteum cyst
220
typical measurement for corpus luteum cyst
221
color flow of corpus luteum
ring of increased vascularity
low resistance
high diastolic
222
when should a corpus luteum cyst regress by
16-18 weeks
223
what can corpus luteum cyst mimmic (4)
hematosalpinx
ectopic pregnancy
ovarian neoplasm
hematomas
