OBG Radiology Case - Ectopic Pregnancy

Question 1

What uterine imaging findings suggest possible ectopic pregnancy?

Answer 1

1. Empty uterus with no gestational sac and a beta-HCG above 2000 mIU/mL (discriminatory level) is suspicious for an ectopic pregnancy

Question 2

List 5 sonographic adnexal findings that can be seen in a tubal ectopic pregnancy.

Answer 2

1. Adnexal mass separate from the ovary
2. Complex mass or fluid-filled gestational sac
3. Fetal pole may be present or absent
4. Embryo may or may not have cardiac activity, depending upon age and viability. A detectable heartbeat confirms the diagnosis
5. Most visualized between the uterus and the ovary
6. Possible free fluid; peritoneal free fluid that is echogenic or complex is never physiologic, and in this scenario almost always represents hemoperitoneum from a ruptured ectopic

Question 3

The ___ is the site of 98% of all ectopic gestations.

Answer 3

Fallopian tube

Question 4

75-80% of implantations occur in the ___ of the fallopian tube.

Answer 4

Ampullary tubal segment

Question 5

What is the sensitivity and specificity of identifying an ectopic pregnancy on U/S when free peritoneal fluid is identified and when there is a tubal mass?

Answer 5

Free fluid:
Sensitivity - 96%
Specificity - 99%

Tubal mass:
Sensitivity - 81%
Specificity - 99%

Question 6

What are the initial modalities used to evaluate a suspected ectopic pregnancy?

Answer 6

TV and TA pelvic U/S (TV > TA)

Question 7

TV US can be useful as soon as ___ (time) after a missed menses with a serum beta-hcg >1500.

Answer 7

1 week

Question 8

What is the utility of a transabdominal pelvic U/S in evaluating for ectopic pregnancy?

Answer 8

Larger field of view
May be able to identify free fluid or an extra-ovarian adnexal mass
ID of pregnancy products in the fallopian tube is more difficult
A uterine pregnancy is usually not recognized until 5-6 weeks or 28 days after timed ovulation

Question 9

What is the utility of color doppler in evaluating ectopic pregnancy?

Answer 9

Identifies sites of increased vascularity; if vascular color is seen in a “ring of fire” pattern around a gestational sac in an extra-uterine location, this support the diagnosis of ectopic pregnancy

Question 10

What is the appropriateness criteria for evaluating acute pelvic pain in a female or reproductive age + positive beta hcg?

Answer 10

TV and TA U/S should be initial studies with Doppler as an adjunct; if U/S is inconclusive or non-diagnostic an MRI of the abdomen and pelvis can be performed; CT is not recommended due to radiation risk

Question 11

True or false - 50+% of women with ectopic pregnancies will have no significant risk factors.

Answer 11

True

Question 12

List 6 risk factors for ectopic pregnancy.

Answer 12

1. Infertility treatment
2. Prior ectopic pregnancy
3. Prior PID
4. IUD in place
5. Tubal abnormality
6. Previous abdominal or tubal surgery

Question 13

What is the prevalence of ectopic pregnancy?

Answer 13

1.4%

Question 14

Ectopic pregnancy accounts for ___% of maternal deaths.

Answer 14

25

Question 15

How does ectopic pregnancy present (symptoms)?

Answer 15

Vaginal bleeding, palpable adnexal mass, pelvic pain = classic picture (only 45% present this way)

Abdominal pain radiating to the shoulder may be associated with ectopic rupture irritating the diaphargm

Urge to defect due to fluid in the posterior cul de sac from rupture

Question 16

How does ectopic pregnancy present (physical findings)?

Answer 16

75% - abdominal tenderness +/- rebound tenderness

66% - cervical motion tenderness

50% - palpable adnexal mass

20% - hemodynamic compromise (orthostasis, hypotension, shock)

Often unremarkable findings if the ectopic pregnancy is small and unruptured