Brainscape's Knowledge GenomeTM

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


See full index

Urogenital System > Ultrasound in Obstetrics > Flashcards

Ultrasound in Obstetrics Flashcards

1
Q

What is an Obstetric Ultrasound

A

Obstetric Ultrasound is the use of ultrasound scans in pregnancy

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

What is the name of the equipment used in ultrasund scans

A

Real-Time Scanners

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

Explain briefly how Real time scanners work

A

Sound waves are emitted from a transducer that is placed in contact with the maternal abdomen

It is moved around to look at any particular content of the uterus

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

What is a requirement for an ultrasound in early pregnancy

A

full bladder

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

What are the 7 main uses of ultrasonography

A
  • Diagnosis and confirmation of early pregnancy
  • Vaginal bleed during early pregnancy
  • Determination of gestational age and fetal size
  • Detection of abnormalities
  • Polyhydramnios and Oligohydramnios
  • Multiple Pregnancies
  • Placental localization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The gestational sac can be visualized as early as which week

A

4 1/2 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When can the yolksac be observed

A

5 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When can the embryo be observed and measured

A

5 1/2 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the normal heart rate at 6 weeks

A

90-110 bpm

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

What is the normal heart rate at 9 weeks

A

140-170 bpm

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

How is the diagnosis of a missed abortion usually made

A

by serial ultrasound scans demonstrating lack of gestational development

if ultrasound demonstrates a 7mm embryo but cannot demonstrate a clearcut heartbeat, a missed abortion may be diagnosed

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

What are the five standard biometric parameters to estimate gestational age and /or foetal weight

A 
Crown Rump Length (CRL)
Biparietal Diameter (BPD)
Head Circumference
Abdominal Circumference (AC)
Femur Legth (FL)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When should the Crown-Rump measurement be made

A

Between 7-13 weeks

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

Which biometric parameter to estimate gestational age and/or fetal weight is best studied and highly reproducible

A

Biparietal Diameter

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

BPD can be used to predit gestational age when measured between which weeks of pregnancy

A

14-20

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

BPD can be used to predict gestational age within what range

A

+/-7 days

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

What is the plane that both the BPD and Head Circumference are measured on

A

Measured on a plane of section that intersect the thalami and the third ventricle

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

Which is the single most important measurement in late pregnancy

A

Abdominal Circumference

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

Why is abdominal circumference the most important measurement in late pregnancy

A

serial measurements useful in monitoring growth

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

What is the “Femur Length” used to measure

A

Measures the longest bone in the body and reflects the longitudinal growth of the fetus

21
Q

The femur increases from what length at 14 weeks to what length at term

A

1.5cm at 14 weeks to 7.8 cm at term

22
Q

What is nuchal translucency?

A

It is a term used to describe sonographic appearance of a collection of fluid under the skin behind the fetal neck at 11-13 weeks of pregnancy

23
Q

What abnormalities can Nuchal Transluceny detect?

A

Down’s Syndrome
Trisomy 21

24
Q

Structural abnormalities in the foetus can be detected by which week of pregnancy

A

Week 20

25
Q

List 2 soft markers for chromosomal abnormalities in the first trimester

A
  • Absence of foetal nasal bone (Cleft Palate)
  • An increased foetal nuchal translucency (Downs’ Syndrome)
26
Q

Disitinguish between hydramnios and oligohydramnios

A

Polyhydramnios is excessive amniotic fluid while oligohydramnios is a decreased amount of amniotic fluid

27
Q

Which scan is considered indispensible in early diagnosis of ectopic pregnancy

A

Transvaginal Scan

28
Q

How is doppler frequency obtained?

A

From the phase shift
T2(time of returned signal)- T1(time of omitted signal)

29
Q

How is Doppler Frequency obtained?

A

It is obtained by measuring the time difference for the signal to be returned when reflected from moving scatters

30
Q

Doppler Ultrasound is most widely employed in the detection of

A

Fetal Cardiac Pulsations

31
Q

What are the two routes of doppler examinations

A

Abdominal
Transvaginal

32
Q

What is the name of the handheld device that is commonly used to detect fetal heartbeat

A

Doptone

33
Q

Doppler Flow Velocity Waveforms are used to assess

A

Blood Flow Characteristics in foetal blood vessels

34
Q

Describe the appearance of Umbilical Artery flow in the Doppler

A

Saw-tooth appearance of arterial flow in one direction and continuous umbilical venous flow in the other

35
Q

reversed Diastolic velocity (REDV) can be seen in

A

Severe Intrauterine Growth Restriction

36
Q

True of False

Volume flow in the Umbilical Arteries increases with advancing gestation

A

True

37
Q

Which method is particularly indispensible in the diagnosis and assessment of congenital heart abnormalities

A

Colour Flow Mapping

38
Q

What is the difference between power doppler and Doppler Flow Velocity

A

Power Doppler does not use flow velocity information to visualize slow flow in smaller blood vessels

39
Q

What is one disadvantage of Power Doppler

A

It does not display flow direction or different velocities

40
Q

List four advantages of 3D scans

A

-Impressive to parents
- Increasing psychological bonding between the parents and the baby
- More accurate volumetric measurements
- the presence or absence of abnormalities are better appreciated

41
Q

Which ultrasound technique is used to detect more subtle features: low set ears, facial dysmorphia, clubbing of feet

A

3D Ultrasound

42
Q

The ability to obtain a good 3D picture depends on what variables

A

operator skill, amount of liquor (amniotic fluid)
foetal position
maternal obesity

43
Q

When is the first scan generally booked in pregnancy

A

7 weeks

44
Q

What is the aim of the first scan?

A

To detect:
-congenital malformations
-exclude multiple pregnancies
-verify dates and growth
-determine placental position

45
Q

When is the second scan done

A

18-20 weeks

46
Q

What is the aim of the second scan

A

To detect congenital malformations
Exclude multiple pregnancies
Verify Dates and Growth
Determine Placental position

47
Q

When is the 3rd scan doen

A

week 34

48
Q

What is the aim of the third scan

A

-evaluate foetal size
-assess foetal growth

Urogenital System (17 decks)

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