fetal and obstetric imaging

Question 1

indications of utz

Answer 1

locating pregnancy
identifying number of embryos
aiding in prenatal diagnosis
estimating gestational age
evaluating suspected trophoblastic ds

Question 2

what to look for in utz?

Answer 2

gestational sac, shape, location and number
presence/absence of embryo
CRL & YS
presence/absence of fetal cardiac motion w/ m-mode
measure YS AP diameter, check shape
evaluate for subchorionic hemorrhage
evaluate adnexal mass
document presence/absence of free fluid
document length & status of cervix
measure nuchal translucency

Question 3

utz findings of early pregnancy

Answer 3

GS
MSD
YS
fetal pole
CRL

Question 4

confirming intrauterine gestation (3)

Answer 4

double decidual sign
intradecidual sign
double bleb sign

Question 5

first sign of early pregnancy on TVS at approx. 3-5 wks when MSD is 2-3mm

Answer 5

GS

Question 6

true GS can be distinguished from pseudogestational sac by?

Answer 6

normal eccentric location and embedded in endometrium

Question 7

double decidual sign is seen at _wks?

Answer 7

4.5-5 wks

Question 8

YS is seen at _wks?

Answer 8

5.5 wks

Question 9

discriminatory hCG with TVS vs TAS

Answer 9

TVS: 1000-2000 IU/L
TAS: >6500 IU/L

Question 10

MSD is seen at _wks?

Answer 10

3 wks

Question 11

MSD >25mm w/ absent fetal pole interpretation

Answer 11

pregnancy failure

Question 12

MSD 16-24mm w/o embryo interpretation

Answer 12

suspicious pregnancy failure

Question 13

MSD 8mm, YS should be visible, absence of YS is an indication of pregnancy failure, T or F?

Answer 13

false (absence of YS is not an indication of pregnancy failure)

Question 14

first anatomical structure identified w/in GS

Answer 14

YS

Question 15

site of initial hematopoiesis

Answer 15

YS

Question 16

YS involutes at _wks and undetectable after _wks

Answer 16

11 wks

14-20 wks

Question 17

appear circular thick-walled echogenic structure w/ an anechoic center w/in GS but outside amniotic membrane

Answer 17

YS

Question 18

YS is seen in TVS at _wks while in TAS at _wks

Answer 18

TVS: 5.5 wks (MSD 8-10m)
TAS: 7 wks (MSD 20mm)

Question 19

first direct imaging manifestation of fetus

Answer 19

fetal pole

Question 20

seen as thickening on the margin of YS

Answer 20

fetal pole

Question 21

fetal pole is seen in TVS at _wks while in TAS at _wks

Answer 21

TVS: 6 wks (MSD >16mm)
TAS: 6.5 wks (MSD >25mm)

Question 22

most accurate estimation of gestational age in early pregnancy

Answer 22

CRL

Question 23

CRL is used as primary measure of gestational age at _wks

Answer 23

7-13 wks

Question 24

cardiac activity should be present in embryo w/ CRL _mm

Answer 24

> 7mm

Question 25

findings confirming dx of IUP

Answer 25

DDS at 4.5-5 wks GS + YS at 5 wks GS + YS + embryo at 5.5-6 wks CRL>5mm + FHT

Question 26

initially eccentric, rounded or oval fluid filled collections seen at 4.5-5 wks

Answer 26

DDS

Question 27

visualization of GS containing YS & AS giving appearance of two bubbles

Answer 27

DBS

Question 28

threshold & discriminatory level of IDSS

Answer 28

T: 24 days AOG D: 47 days AOG

Question 29

this occurs when there is perigestational hemorrhage & blood collects between uterine wall and chorionic membrane. frequent cause of 1st & 2nd trim. bleeding

Answer 29

subchorionic hemorrhage

Question 30

this is the normal fluid-filled SQ spaceidentified at the back of the fetal neck during late 1st trim. & early 2nd trim.

Answer 30

nuchal translucency

Question 31

conditions associated w/ NT thickening

Answer 31

``` aneuploidy trisomies turner syndrome non-aneuploidy structural defects & syndromes congenital heart ds noonan syndrome congenital diaphragmatic herniation omphalocele skeletal dysplasia smith-lemli-opitz syndrome VACTERL association miscarruage Parvo B19 ```

Question 32

at what wks is considered a routine investigation advised for NT scan?

Answer 32

11-13 wks

Question 33

what are the 3 traditionally used factors to calculate the risk of trisomies

Answer 33

CRL NT FHR

Question 34

what are the 3 additional markers used to increase detection rate & reduce false-positive rate

Answer 34

nasal bone DV flow tricuspid flow

Question 35

most accurate reflection of gestational age in 2nd trim.

Answer 35

BPD

Question 36

BPD low for GA interpretation

Answer 36

dolicocephaly

Question 37

BPD high for GA interpretation

Answer 37

brachycephaly

Question 38

correct plane for BPD & HC must include the ff (3)

Answer 38

cavum septum pellucidum thalamus choroid plexus in atrium of lateral ventricles

Question 39

reflects growth of intraabdominal organs as well as fetal weight/size

Answer 39

AC

Question 40

AC measures peripheral circumference of fetal abdomen excluding the SQ tissue, T or F?

Answer 40

false (including the SQ tissue)

Question 41

landmarks of AC (3)

Answer 41

portal sectioon of UV stomach spine

Question 42

it serves as monitor for growth of long bones

Answer 42

FL

Question 43

placenta can be seen as early as _wks in TVS

Answer 43

8 wks

Question 44

normal placental aging is by appearances of? (2)

Answer 44

hypoechoic areas & calcifications

Question 45

grade of placenta w/c appears as relatively homogenous in echotexture & retroplacental space is hypoechoic

Answer 45

normal placenta

Question 46

grade of placenta w/c appears w/ small diffuse calcifications randomly distributed in placenta w/ subtle indentations w/in the chorionic plate

Answer 46

grade 1

Question 47

grade of placenta w/c appears w/ larger calcifications & large indentations along the chorionic plate

Answer 47

grade 2

Question 48

grade of placenta w/c appears w/ complete indentations along the chorionic plate & more irregular calcifications

Answer 48

grade 3

Question 49

this fluid protects fetus from injury; allows growth & fetal mvmt; and essential for normal lung maturation

Answer 49

amniotic fluid

Question 50

oligohydramnios is defined as AFI below?

Answer 50

5cm

Question 51

causes of oligohydramnios

Answer 51

IUGR urinary tract abnormalities PROM postterm

Question 52

polyhydramnios is associated with?

Answer 52

maternal DM GI & CNS anomalies lethal skeletal dysplasia chromosomal anomalies

Question 53

polyhydramnios is defined as AFI more than?

Answer 53

20cm

Question 54

2nd trim. utz findings

Answer 54

``` fetal number (amniocity & chorionicity) fetal cardiac activity fetal presentation placental location, appearance AFV GA assessment fetal wt fetal anatomical survey eval of maternal uterus, adnexa, & cervix ```

Question 55

FL/AC >23.5 suggests?

Answer 55

IUGR

Question 56

FL>AC suggests?

Answer 56

growth retarded baby