CHAPTER 10: Fetal Imaging

Fetal Imaging

The thermal index, the temperature elevation that potentially can induce fetal injury, is increased in which of the following?

a. Pulsed Doppler imaging

b. Longer examination time

c. Locations near fetal bone

d. All of the above

d Fetal Safety

A 25-year-old with irregular menstrual periods presents with a suspicion of pregnancy. A transvaginal ultrasound is performed with these results. What gestational age should be assigned to the pregnancy?

a. 7 weeks 4 days

b. 8 weeks 0 days

c. 8 weeks 6 days

d. None of the above

b Table 10-1

What is the standard error for ultrasound estimates of fetal weight after the first trimester?

a. 5%

b. 10%

c. 20%

d. 33%

c Gestational Age Assessment

What fetal conditions might explain the head measurements seen below?

a. Normal fetus

b. Oligohydramnios

c. Fetal neural-tube defect

d. All of the above

d Gestational Age Assessment

Sonographic evaluation of all except which of the following are best achieved in the first trimester?

a. Adnexa

b. Cervical length

c. Ectopic pregnancy

d. Chorionicity of twins

b First-Trimester Sonography

A 42-year-old woman presents with vaginal spotting. She has not had a period for 2 months and believes she is perimenopausal. A transvaginal ultrasound is performed in her gynecologist’s office. What is the minimum mean sac diameter measurement necessary to diagnose an anembryonic pregnancy with certainty?

a. 7 mm

b. 10 mm