Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

LMC Ultrasound > OB test 2 ch. 47-51 > Flashcards

OB test 2 ch. 47-51 Flashcards

1
Q

cavity where the fetus exists

A

amniotic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

hCG

A
  • secreted by trophoblastic cells
  • indicates pregnancy
  • FIRST TRIMESTER: hCG levels should double every few days (or every 48 hrs) then will likely decrease after the first trimester.
  • blood hCG should be positive 7-10 days conception age
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

primary yolk sac vs secondary yolk sac

A
  • at 23 days menstrual age, the primary yolk sac is pinched off, forming the secondary yolk sac.
  • we only see the secondary yolk sac under ultrasound
  • Secondary yolk sac contains the amniotic and chorionic cavities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how do we (sonographers) date a pregnancy? what method do we use?

A
  • sonographers use gestational age (also known as menstrual age) to date pregnancy.
  • the first day of the last menstrual period (LMP) as the beginning of the gestation.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how do embryologists date a pregnancy?

A

-embryologists use conceptual age (also known as embryologic age) with conception being the first day of pregnancy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

decidua basalis

A
  • the portion on the myometrial side or burrowing side.
  • the part of the decidua that unites with the chorion to form the placenta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

decidua capsularis

A
  • the villi covering the developing embryo.
  • the part of the decidua that surrounds the chorionic sac
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

double decidual sac sign

A
  • reliable sign of an early pregnancy
  • its the interface between the decidua capsularis and the endometrial cavity.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

when do hCG levels begin to plateau?

A

9-10 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

if hCG levels are super high, its an indication of…

A

molar pregnancy OR multiple pregnancies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

if hCG levels don’t double like they should (in the first trimester) its an indication of…

A

ectopic pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

when does the amnion and chorion fuse together?

A

at the end of the third month of gestation.

-chorioamniotic fusion occurs at approx. 14 to 15 weeks (chp 47 p.p)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

when does a fetus’ heart begin to beat? when can we see this under ultrasound?

A

-the heart begins to beat at 36 days -we can see heart tones under ultrasound at 46 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how to calculate mean sac diameter (MSD) ?

A

its the average sum of the length, width, and height of the gestational sac.

length (mm) + width (mm) + height (mm) /3 = MSD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

When should we expect to see the yolk sac & Embryo?

A

4-5 weeks; Embryo seen at 4 weeks as echogenic curved structure adjacent to yolk sac (chp 45 p.p.)

Yolk sac should be seen when MSD >12 mm

Embryo should be seen when MSD >18 mm

*These measurements vary depending on which source is used*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When does bowel begin to herniate back into the fetus?

A

11 weeks; Bowel herniates out at 8-11 weeks, then returns to abdominal cavity (chp 45 p.p.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What measurement should the yolk sac not exceed?

A

>6mm (chp 47 p.p.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Cystic area in the head that is a normal structure, but can be confused with pathology?

A

Rhombencephalon (chp 47 p.p.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What hormones do the corpus luteum secrete?

A

Progesterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Decidua Parietalis

A

The altered endometrium lining the main cavity of the pregnant uterus other than at the site of attachment of the chorionic sac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Fertilization occurs within this region 1 to 2 days after ovulation

A

-fertilization most often occurs in the Ampulla portion of the fallopian tube A mature ovum is released and enters the distal fallopian tube via the fimbriae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Stages of fertilization

A

Fertilization occurs at distal end of fallopian tube, days 1-2. Fertilized conceptus is now referred to as a zygote which undergoes rapid cellular division to form the 16-cell morula, days 3-4. Further cell proliferation bring the morula to the blastocyst stage, days 4-5. Implantation happens within 12 days post fertilization into the uterine decidua Figure 47-1 p.1065

  • 12 days after conception (during implantation) conceptus is called zygote
  • from time of implantation until end of 10th week menstrual age, conceptus is called embryo
  • after 10 weeks, now called fetus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How many weeks should we be able to evaluate cranial anatomy?

A

28 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Anencephaly

A

absence of brain and cranial vault, most common cerebral abnormality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Pelvic mass in 1st tri

A

Corpus luteum cyst most common ovarian mass seen in 1st tri

Fibroids are also common and increase in size in 1st tri due to estrogen stimulation

(Chapter 48)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Sub chorionic hemorrhage

A

most common cause of bleeding in the first trimester

Hemorrhage occurs between myometrium and margins of gestational sac due to process of implantation of fertilized ovum into endometrial cavity & myometrial wall.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is the most common location for an ectopic pregnancy?

A

Fallopian tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the most life threatening location for an ectopic pregnancy?

A

Interstitial portion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which ectopic pregnancy location causes loss of uterus?

A

Cervix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How much gestational sac grows?

A

1mm per day in early pregnancy. Chapter 47

31
Q

Most important finding in ectopic pregnancy

A

Uterine cavity empty, adnexal mass present. Chapter 48

32
Q

At what hCG level can a normal gestational sac be see when transabdominal sonography is used?

A

1800 mIU/ml

33
Q

When transvaginal sonography is used, what is the hCG level?

A

1000 mIU/ml

34
Q

Normal heart rate during the first trimester

A

between 90-170 bpm

35
Q

Bradycardia

A

Slow heart rate; less than 90 bpm

36
Q

Tachycardia

A

Fast heart rate; greater than 170 bpm

37
Q

How to determine a normal early gestational sac vs a pseudogestational sac

A
  1. Pseudogestational sacs do not contain a living embryo or yolk sac 2. Pseudogestational sacs are centrally located within the endometrial cavity, unlike the burrowed gestational sac, which is eccentrically placed 3. Homogeneous level echoes are commonly observed in pseudo gestational sacs, unlike in normal gestational sacs Presence of a yolk sac positively indicates an intrauterine gestation
38
Q

Pseudogestational sac

A

Decidual reaction with fluid occurring within the uterus in a patient with an ectopic pregnancy. 20% of patients with ectopic pregnancy demonstrate intrauterine saclike structure

39
Q

Blighted Ovum

A

Also known as anembryonic pregnancy. Happens when a fertilized egg attaches itself to the uterine wall, but the embryo does not develop. Cells develop to form the pregnancy sac, but not the embryo itself. Occurs within the first trimester, often before a woman knows she is pregnant. A high level of chromosome abnormalities usually causes a woman’s body to naturally miscarry

–no yolk sac, embyro, or amnion will be seen

40
Q

Missed abortion

A

No heart tones and the gestational sac is >8mm

41
Q

Molar pregnancy

A

Result of a genetic error during the fertilization process that leads to growth of abnormal tissue within the uterus. Molar pregnancies are also called gestational trophoblastic disease (GTD), hydatidiform mole or simply referred to as a “mole.”

Snowstorm or grape-like appearance throughout uterus

*hCG levels will be >100,000 IU/mL

42
Q

Abortion in progress

A
43
Q

Normal gestational sac (images)

A
44
Q

When do we start to perform individual measurements-what age?

A

Anatomy evaluation starts at 20 weeks, so this may be when individual measurements begin?

45
Q

Serial beta hCG

A

Serial hCG blood tests are two quantitative hCG blood tests done two to three days apart. In early pregnancy, the hCG level usually doubles roughly every two to three days. If the hCG doubling time is slower or if the level decreases over time, this is a possible sign of miscarriage or ectopic pregnancy.

46
Q

At what weeks can we start to see the bladder in the fetus?

A

Fetal urinary bladder becomes sonographically apparent at 10 to 12 weeks of gestation

47
Q

Gastroschisis

A

Congenital defective opening in the wall of the abdomen just to the right of the umbilical cord; bowel and other organs may protrude outside the abdomen from this opening

48
Q

Omphalocele

A

Congential anterior abdominal wall defect in which abdominal organs (liver, stomach, bowel) are atypically located within the umbilical cord and protrude outside the wall; highly associated with cardiac, central nervous system, renal, and chromosomal anomalies; it develops when there is a midline defect of the abdominal muscles, fascia, and skin

49
Q

Visualization of spine and cranium

A

Embryonic head can sonographically by identifies by 7 weeks but ossification of cranium begins at 9 weeks. This is when falx cerebri develops, separating ventricles.

Ventriculomegaly not seen until 11 weeks.

spine & cranium begin developing at 6 weeks

cerebral hemispheres by 9 weeks

cerebellum by 10 weeks

Frontal bones calcify at 9 weeks

50
Q

Acrania

A

Is complete or partial absence of the cranial bones

51
Q

Cystic hygroma

A

Is one of the most common abnormalities seen sonographically in the first trimester.

Hgh association with chromosomal abnormalities-most common trisomies 13, 18, 21

Cystic spaces develop behind the back of the neck.

52
Q

What stage do corpus luteum cysts regress?

A

As pregnancy progresses, corpus luteum cysts regress; typically not seen beyond 16 to 18 weeks’ gestation

53
Q

At how many weeks can we see:

  • stomach
  • kidneys
  • adrenal glands
  • abdominal wall
A

Stomach: 11 weeks and should be fully developed by 16 weeks

Kidneys: 13 weeks

Adrenal glands: 20 weeks

Anterior abdominal wall: 6 weeks

54
Q

Heterotopic pregnancy

A
  • Simultaneous intrauterine and extrauterine pregnancy
  • Higher risk from ovulation induction and in vitro fertilization with embryo transfer
55
Q

Dolicocephaly

A
56
Q

Brachycephaly

A
57
Q

Symmetrical IUGR

A

Result of 1st trim. insult, such as chromosomal abnormality or infection.

Results in fetus proportionately small throughout pregnancy

**IUGR= fetal weight at or below 10% for given gestational age (10th percentile)

58
Q

Asymmetrical IUGR

A

Begins late in second or third trimester from placental insufficiency

Specific parts are affected instead of entire fetus small. Head sparred at expense of abdominal and soft tissue growth and fetal length compromised.

Drug use can cause this.

59
Q

What is the condition causing midline cranial defect in which there is herniation of the brain and meninges?

A

Cephalocele

*in Western Hemisphere, primarily occipital lobe is affected*

60
Q

Holoprosencephaly

A
  • malformation that results from failure of prosencephalon to differentiate into cerebral hemispheres & lateral ventricles
  • occurs in weeks 4-8 of gestation
  • causes facial dysmorphism
  • Alobar type is the most serious and consists of single ventricle, small cerebrum, fused thalami, agenesis of corpus callosum, and falx cerebri
61
Q

Turner’s Syndrome

A

Large fluid collection on the back of the neck or other abnormal fluid collections (Increased NT)

Heart abnormalities

Abnormal kidneys

Cystic Hygroma

Infertile due to no ovaries (only 1 X chromosome)

62
Q

Macrosomia

A

birth wt of 4000 g or greater OR above 90th percentile for estimated gestational age

  • Commonly result of poorly controlled diabetes
  • greater risk if mother is over 35, mutliparous, pregnancy wt over 70kg, history of delivering large fetuses…

2 types: mechanical & metabolic

Increase in AC due to large liver, heart, and adrenal glands

Shoulder injuries and cord compression can cause morbidity or mortality.

63
Q

Ductus Arteriosus

A

Shunts fetal blood away from lungs

  • Fetal circulation bypasses fetal lungs because they do not oxygenate blood
  • Oxygenation occurs in the placenta
64
Q

Ductus Venosus

A

Specialized vascular connection that allows oxygen rich blood arriving from the placenta to travel through the umbilical vein, then the IVC on its way straight to the heart.

-it is shunted away from the abdomen to go directly to the heart, then brain.

65
Q

Biophysical profile parameters

A
  1. fetal breathing- need 1 episode lasting 30 seconds
  2. fetal body movements: need 3 in 30 minutes
  3. fetal tone: flex/ext of 1 episode of limbs or trunk
  4. amniotic fluid vol: need 1 pocket of at least 2 cm fluid
66
Q

Pre-term

A

less than 37 weeks gestational age

67
Q

Post-term

A

Baby not yet born after 42 weeks

68
Q

Cord-doppler

A

Often done with BPP

Should not be measured before 25 weeks

S/D ratio typically used to measure

Value of 4.0 or less for 25-29 weeks; decreases as weeks progress

69
Q

Micrognathia

A

abnormally small chin or positioned back too far; common in Down Syndrome

70
Q

Frontal Bossing

A

Forehead that slopes forward and appears too big; seen in skeletal dysplasia & dwarfs

71
Q

When can we see limbs?

A

Not routinely visualized until long bone calcification by 10 weeks

Upper limbs form first, then lower, then hands & feet by 10 weeks

Clavicle: ossification at 8 weeks

72
Q

At 12 weeks what can be see on ultrasound?

A

Genitalia

73
Q

polyhydramnios

A

excessive amounts of amniotic fluid

develops if fetus cannot swallow

74
Q

oligohydramnios

A

insufficient amount of amniotic fluid

occurs if fetal urine output reduces

LMC Ultrasound (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions