OB/GYN Ultrasound

Question 1

Describe the sonographic findings in serous ovarian tumors.

Answer 1

Benign serous tumors (serous cystadenomas) are sharply marginated, anechoic, may be large but are usually unilocular with possible internal thin-walled septations.

Malignant serous tumors (serous cystadenocarcinoma) are usually multilocular with multiple papillary projections or septations.

Echogenic material may be seen within the mass, and ascites may be present.

Serous cystadenocarcinoma is the most common form of ovarian cancer.

Question 2

What is the first structure to be identified sonographically within the gestational sac?

Answer 2

The** yolk sac **is the first structure seen within the gestational sac. With transvaginal sonography, the secondary yolk sac is visible at 5.5 weeks LMP, and is almost always seen when the MSD reaches 8 mm.
Transabdominally the yolk sac should be seen by 7 weeks LMP, when the MSD is 20 mm. The yolk sac should be measured inner-to-inner.

Question 3

What is Dandy-Walker malformation (DWM)?

Answer 3

Dandy-Walker malformation is complete or partial absence of cerebellar vermis and posterior fossa cystic dilatation communicating with the 4th ventricle.

Question 4

Trace the flow of blood through fetal circulation.

Answer 4

Blood flows from the placenta > umbilical vein > left portal vein > ductus venosus > right atrium. Right atrial blood takes two pathways: 60% of blood travels right atrium > foramen ovale > left atrium > left ventricle > aorta. 40% of right atrial blood travels from right atrium > right ventricle > pulmonary artery. The majority of blood in the pulmonary artery travels into the ductus arteriosus > aorta. A small amount of pulmonary arterial blood travels to the lungs > pulmonary veins > left atrium > left ventricle > aorta. Blood in the aorta perfuses fetal tissues and then travels through the internal iliac (hypogastric) arteries > umbilical arteries > placenta.

Question 5

What are the features of VATER (or VACTERL) association?

Answer 5

VATER or VACTERL association includes:

• Vertebral anomalies
• Anal atresia/ imperforate anus
• Cardiac anomalies
• T} tracheoesophageal
• E} fistula
• Renal anomalies
• Limb deformities