Deck 47: Role of Sonography in Obstetrics

Question 1

A sonographer can minimize thermal effects by which one of the following?

A) Not staying in one spot
B) Placing the focus of the beam in the near field
C) Scanning over fetal bone
D) Increasing acoustic output

Answer 1

A

Question 2

Obstetric (OB) ultrasound allows the clinician to assess all of the following except:

A) muscle tone.
B) development.
C) growth.
D) well-being.

Answer 2

A

Question 3

In the second trimester, guidelines recommend images of the fetal head including all of the following except:

A) Sylvian fissure.
B) lateral cerebral ventricles.
C) cerebellum.
D) midline falx.

Answer 3

A

Question 4

The abdominal circumference on a transverse view is measured at the level of all the following structures except:

A) portal sinus.
B) fetal stomach.
C) fetal kidneys.
D) umbilical vein.

Question 5

Interval fetal growth may be determined by sonographic measurements a minimum of ______ weeks apart.

A) 1
B) 2
C) 3
D) 5

Question 6

Which one of the following statements about the embryo heart rate is false?

A) Early in the developmental phase, the heart rate is greater than 190 bpm.
B) Early in the developmental phase, the heart rate is 90 bpm.
C) The rate may increase to 170 bpm in the middle of the first trimester.
D) The rate is 120 to 140 bpm in the second and third trimesters.

Question 7

Which one of the following statements about the gestational sac is false?

A) The earliest structure observed with the sac is the yolk sac.
B) The earliest structure may be seen with transvaginal ultrasound.
C) Blood tests should be positive 7 to 10 hours after conception.
D) The placenta is seen as a thickened density along part of the margin of the gestational sac.

Question 8

Which one of the following statements about the amniotic fluid development is true?

A) The fetal kidneys begin to produce urine in the first trimester.
B) In the first trimester, fluid is produced by the placenta.
C) The fluid decreases in volume until 34 weeks' gestation.
D) The fetus gains two thirds of its weight during the first two trimesters.

Question 9

Limited obstetric ultrasound examinations are ordered for which one of the following reasons?

A) To answer a specific clinical question
B) To determine the fetal gender
C) To screen the fetus for anomalies
D) To rule out an ectopic pregnancy

Question 10

The second trimester is between ___________ gestational weeks.

A) 12 and 21
B) 12 and 28
C) 14 and 26
D) 15 and 30

Question 11

Which one of the following statements about determining fetal age is false?

A) Measure the head circumference at the same level as the biparietal diameter (BPD).
B) Measure the abdominal circumference at the level of junction of the umbilical vein and portal sinus.
C) Measure the femur length on the femur farthest from the transducer.
D) Measure BPD in the axial plane that includes the thalamus and cavum septum pellucidum.

Question 12

The major biologic effects of ultrasound are believed to be which one of the following?

A) Thermal
B) Production and collapse of gas-filled bubbles
C) Cavitation
D) All of the above

Question 13

Biophysical evaluation for fetal well-being includes all of the following except:

A) assessment of amniotic fluid.
B) fetal tone.
C) muscle tone.
D) body and breathing movements.

Question 14

The most accurate measurement of gestational age during the first trimester is which one of the following?

A) Mean sac diameter
B) Yolk sac diameter
C) Biparietal diameter
D) Crown-rump length

Question 15

Which one of the following statements about ultrasound safety is true?

A) No potential biologic effects exist.
B) The energy produced by ultrasound machines today is lower than that produced by earlier equipment.
C) Continual research on the bioeffects of ultrasound is no longer necessary.
D) Studies on the bioeffects of ultrasound are not definitive.

Question 16

Ultrasound is able to determine all of the following except:

A) source of bleeding and status of fetus.
B) fetal presentation.
C) multiple gestation.
D) exact date of delivery.

Question 17

On transabdominal imaging, an overdistended bladder may give a false impression of which one of the following?

A) Incompetent cervix
B) Placenta previa
C) Fetal position
D) Fetal size

Question 18

Fetal anatomy may be adequately assessed after ______ weeks' gestation.

A) 14
B) 16
C) 18
D) 21

Question 19

Even with a known menstrual date, conception may occur from day _____ to day _____.

A) 1; 15
B) 6; 27
C) 10; 18
D) 15; 27

Question 20

The dates established by sonography examinations performed in the second trimester typically take precedence over the menstrual age when the discrepancy is greater than _______ days.

A) 5
B) 7
C) 10
D) 15

Question 21

When is the nuchal translucency examination performed?

A) During the first trimester
B) During the second trimester
C) During the third trimester
D) Throughout pregnancy

Question 22

Diagnostic ultrasound has been in use since late in which one of the following decades?

A) 1940s
B) 1950s
C) 1960s
D) 1970s

Question 23

Fetal sonography with or without Doppler should be performed:

A) on all second-trimester pregnancies.
B) on all first-trimester pregnancies.
C) with a valid medical reason.
D) for sex determination.

Question 24

The purpose for certification in diagnostic sonography is to assure the public that the sonographer has which one of the following?

A) Necessary knowledge to perform the examination
B) Necessary skills to perform the examination
C) Necessary experience to perform the examination
D) All of the above