1st Trimester US (10-14 Weeks)

Question 1

What do you look for in the Extremities?

Answer 1

Four limbs (each with three segments), Hands and feed in normal orientation

Question 2

What do you look for in the placenta?

Answer 2

Normal size, texture, 3 vessel cord

Question 3

What do you look for in the head (not face)?

Answer 3

Presence of head, Cranial Bones, Midline Falx, Choroid Plexus Filled Ventricles.

Question 4

Diagnosis?

Answer 4

Omphalocele (Exomphalos) because you see the membrane, (Remember physiologic herniation resolved by 11-12 weeks)

Question 5

What do you look for in the spine?

Answer 5

Intact overlying skin line, Vertebrae

Question 6

Diagnosis?

Answer 6

Encephalocele

Question 7

Things you never detect?

Answer 7

-ACC, Cerebellar hypoplasia -Duplex Kidneys, Hydronephrosis, Renal Agenesis -CCAM, Extralobar Sequestration -Duodenal Atresia, Bowel Obstruction

Question 8

How do you date twins with size discrepancy?

Answer 8

Go by the bigger twin

Question 9

Diagnosis?

Answer 9

Gastroschisis

Question 10

Diagnosis?

Answer 10

Micrognathia

Question 11

Diagnosis?

Answer 11

Lethal Skeletal Dysplasia (Frontal Bossing, chest:abdomen small)

Question 12

What do you look for in the Abdomen?

Answer 12

Stomach in the LUQ, Bladder, Kidneys

Question 13

What do you look for in abdominal wall?

Answer 13

Normal cord insertion, no umbilical defects

Question 14

What do you look for in the heart?

Answer 14

Regular Cardiac Activity, Four symmetrical chambers

Question 15

Things you should always detect?

Answer 15

Acrania, Anencephaly, Ectopia Cordis, and Encepalocele

Question 16

Diagnosis?

Answer 16

Megacystis

Question 17

Diagnosis?

Answer 17

Alobar Holoprosencephaly

Question 18

What do you look for inside the chest (except heart)?

Answer 18

Symmetrical lung fields, No effusions or masses

Question 19

What do you look for in the neck?

Answer 19

Nuchal translucency

Question 20

Diagnosis?

Answer 20

Sacrococcygeal Teratoma (Why?, it’s in front of the spine, and Intracranial translucency makes spina bifida less likely)

Question 21

Megacystis, critieria? Likely diagnoses based on size?

Answer 21

>7mm criteria for Megacystis.

7mm-16mm think Chromosomal

>16mm think Lower Urinary Tract Obstruction

Question 22

Diagnosis?

Answer 22

Acrania / Exencephaly / Anencephaly Sequence

Question 23

What do you look for in the face?

Answer 23

Eyes (w/ Lens), Nasal bone, profile/mandible, Lips Intact.

Question 24

Criteria for measurement of a CRL?

Answer 24

1) Midline Sagittal section of whole embryo/fetus
2) As horizontal as possible
3) Fills most of the width of the screen
4) Neutral position (not flexed or extended)
5) Clear endpoints to crown and rump
6) Amniotic fluid visible between chin and chest