Chapter 51- Sonography Of 2nd/3rd Trimesters Flashcards Preview

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Flashcards in Chapter 51- Sonography Of 2nd/3rd Trimesters Deck (89)
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1
Q

Anatomy is accurately assessed at how many weeks gestation?

A

18 weeks

2
Q

First two things to look at during examination:

A

Fetal position and cardiac activity

3
Q

Fetal positions change less frequently after ___

A

34 weeks

4
Q

Fetal lie is described in relation to

A

Maternal long axis

5
Q

Fetus head down:

A

Vertex/cephalic

6
Q

Fetal head up:

A

Breech

7
Q

Thigh flexed at hips and lower legs extended in front of the body & up in front of the head

A

Frank breech

8
Q

Both hip and lower extremities are found in the lower pelvis…needs to be delivered by c-section

A

Complete breech

9
Q

Hips extended and one or both feet are the presenting parts closest to the cervix

A

Footling breach

10
Q

Imaging of the brain and skull is done in a _____ plane

A

Transverse

11
Q

Normal brain parenchyma appears

A

Hypoechoic

12
Q

The fetal brain becomes more difficult to visualize as pregnancy progresses because

A

Calcification of the skull

Fetal head moves deeper in the maternal pelvis

13
Q

Superior cranial structures include

A
  • Choroid plexus

- Lateral ventricles

14
Q

Produces cerebrospinal fluid

A

Choroid plexus

15
Q

Echogenic been like/tear shaped structures

A

Choroid plexus

16
Q

Occasionally small cyst can be seen in the choroid plexus in normal pregnancy. This can also be associated with

A

Trisomy 18

17
Q

Cerebrospinal fluid can become trapped during early development resulting in the formation of

A

CP cyst(s)

18
Q

The lateral ventricle should measure

A

Less than 10 mm

19
Q

The lateral ventricles are measured at the level of the ___ in a transverse plane

A

Atria

20
Q

Midline cranial structures

A
  • Cavum septum pellucidum(CSP)
  • Midline falx
  • Thalamus
  • Corpus callosum
21
Q

Midline hyperechoic line that divides the cranial structures into right and left

A

Midline falx

22
Q

Straddles the midline falx, looks like a heart or arrowhead

A

Thalami

23
Q

Between the thalami lies the cavity of the

A

3rd ventricle

24
Q

Boxed shaped echogenic lines straddling the midline falx

A

Cavum Septum Pellucidum

25
Q

The CSP is ___ to the thalamus

A

Anterior

26
Q

Hypoechoic structure seen in the transverse plane as the band of tissue between the frontal tissue between the frontal ventricular horns

A

Corpus callosum

27
Q

Inferior cranial structures

A
  • Cerebral peduncles
  • Circle of Willis
  • Cerebellum
  • Cisterna Magna
  • Nuchal fold
28
Q

Appears as a highly pulsatile triangular region.

A

Circle of Willis

29
Q

Cerebellum is ____ shaped

A

Peanut

30
Q

Located directly behind the cerebellum, filled with cerebrospinal fluid

A

Cisterna magna

31
Q

A normal cisterna magna measures

A

3-11mm average— 5-6

32
Q

In the second trimester the nuchal fold is measured in a plane containing the

A

Cerebellum and Cisterna Magna(CM)

33
Q

At 20 weeks or less, a measurement of _____ is normal

A

5mm or less

34
Q

Nuchal fold measurement is unreliable after

A

20 weeks

35
Q

Fetuses with thickened Nuchal skin are at risk for

A

Aneuploidy

36
Q

The fetal ventricular system contains what substance?

A

CSF

37
Q

CSF coats the:

A

Brain and spinal cord

38
Q

The fetal ventricular system flow:

A
  1. lateral ventricles
  2. foramen Monroe
  3. 3rd ventricle(between thalami)
  4. aqueduct of Sylvius
  5. 4th ventricle
  6. foramen of Magendi(medial), foramen of Luscha(lateral)
  7. Cerebral & subarachnoid spaces
  8. Venous system
39
Q

The most common type of fetal hydrocephaly

A

Aqueduct stenosis at the level of the aqueduct of sylvius

40
Q

Aqueduct stenosis at the level of the aqueduct of sylvius will result in

A

Excess fluid in the lateral and 3rd ventricles

41
Q

Inner Orbital Distance(IOD) measurement should be made from

A

Medial border to opposite medial border

42
Q

Outer Orbital Distance(OOD) is measured from the

A

Lateral border to opposite lateral border

43
Q

Outpouching on brain

A

Anterior cephaloceles

44
Q

Small chin:

A

Micrognathia

45
Q

Abnormal forehead slope-more prominent than normal

A

Frontal bossing

46
Q

Small/absent nasal bone is risk factor for

A

Aneuoploidy

47
Q

Large tongue that persistently protrudes outside of the mouth:

A

Macroglossia

48
Q

In LONG, the double lines of the spine is referred to as:

A

Train tracks

49
Q

In TRANS, the spine will visualize

A

3 ossification points

50
Q

Fetal lung tissue appears ____ as pregnancy progresses

A

More echogenic than the liver

51
Q

Standard heart exam requires a ____

A
  • 4 chamber view

- views of the right/left outflow tracts

52
Q

The heart lies more ______ in the fetus than the adult because ___

A

Transverse

Lungs aren’t inflated

53
Q

The apex of the heart is directed toward ___

A

The left anterior chest

54
Q

Echogenic structure that appears within a cardiac chamber and persists despite changing transducer positions is termed

A

Echogenic Intracardiac focus (EIF)

55
Q

Oxygen/nutrient rich blood is carried to the fetal circulation via the

A

Umbilical vein

56
Q

This structure when it doesn’t close during development is called a “hole in the heart”

A

Foramen ovale

57
Q

There are three circulatory shunts in the fetal heart what purpose do they serve

A

Protect the lungs from circulatory overload

58
Q

What are the three circulatory shunt in the fetal heart

A
  1. Ductus Venosus
  2. Foramen ovale
  3. Ductus arteriosis
59
Q

Lies inferior to the heart and lungs and superior to the liver spleen and stomach

A

Diaphragm

60
Q

The muscle that separates the thorax and abdomen

A

The diaphragm

61
Q

What liver lobe is bigger in fetus?

A

Left

62
Q

Why is the left liver lobe bigger?

A

Large quantities of oxygenated blood flows through the ductus venosus to the left lobe

63
Q

The stomach becomes apparent as early as the ____

A

11th week

64
Q

Full stomach should be seen in all fetus is beyond the

A

16th week

65
Q

The echogenicity of the bowel is typically _____ than the liver

A

More echogenic

66
Q

If fetal bowel is as echogenic as the bone it is termed

A

Hyperechoic bowel

67
Q

Hyperechoic Bowel is associated with increased risk for

A

Aneuploidy

68
Q

Kidneys can be seen as early as

A

13 weeks

69
Q

Abnormal renal pelvis measurements before 20 weeks:

A

5mm

70
Q

Abnormal renal pelvis measurements between 20-30 weeks

A

Greater than 8mm

71
Q

Abnormal renal pelvis measurements beyond 30 weeks

A

Greater than 10mm

72
Q

Fetus generally voids (urine) at least ____

A

Once an hour

73
Q

Gender may be appreciated as early as

A

12 weeks

74
Q

Female gender best visualized in :

A

Transverse

75
Q

Female sign:

A

Hamburger sign

76
Q

Fetal labia may appear swollen and edematous due to ___

A

Circulating maternal hormones

77
Q

Scrotum/penis are fairly easily recognized in ____

A

Either plane

78
Q

Fluid seen around the testicles, is a common finding.

A

Hydrocele

79
Q

Male sign:

A

Turtle sign

80
Q

Short femur/humerus is associated with increased risk for

A

Aneuploidy

81
Q

Hands and fingers should be noted whether they ____

A

Are clenched or open/close normally

82
Q

When persistent and abnormal flexion of the ankle is seen, _____ should be expected

A

Club feet

83
Q

___________ is required to measure the cervix

A

Transvaginal

84
Q

Normal cervix measures _____ in pregnancy

A

3cm or longer

85
Q

cervix is shortened, or the internal os appears to have a V or you shape is termed ____

A

Funneling

86
Q

You may be able to differentiate the right from left sides by identifying an atomic landmarks such as

A

Stomach, heart, and spine

87
Q

Stomach is on the

A

Left

88
Q

Heart points to the

A

Left

89
Q

Spine is on the

A

Back