Revisiting ectopic pregnancy: a pictorial essay

Abstract

Ectopic pregnancies occur in approximately 1.4% of all pregnancies and account for 15% of pregnancy-related deaths. Considering the high degree of mortality, recognizing an ectopic pregnancy is important. Signs and symptoms of an ectopic pregnancy are nonspecific and include pain, vaginal bleeding, and an adnexal mass. Therefore, imaging can play a critical role in diagnosis. There are different types of ectopic pregnancies, which are tubal, cornual, cesarean scar, cervical, heterotopic, abdominal, and ovarian. Initial imaging evaluation of pregnant patients with pelvic symptoms is by ultrasonography, transabdominal, transvaginal or both. We review the sonographic appearance of different types of ectopic pregnancies that will aid in accurate and prompt diagnosis.

Keywords: Cervical; cesarean scar; cornual; heterotopic; ultrasonography of ectopic pregnancy.

Figure 1

41-year-old female presenting with pelvic pain later diagnosed with ectopic tubal pregnancy. (a-c) Transvaginal ultrasonography images reveal a solid right adnexal mass (black arrow) demonstrating heterogeneous echogenicity and peripheral color Doppler flow which is separate from the right ovary (not included in this image), measures 2.3 × 2.4 × 2.5 cm (b and c). No intrauterine gestational sac is present.

Figure 2

32-year-old female presenting with pelvic pain and positive pregnancy test diagnosed with ectopic tubal pregnancy. (a-c) Transvaginal ultrasound images reveal a thick-walled rounded structure (black arrow) in the right adnexa with a yolk sac and fetal pole, compatible with a tubal ectopic pregnancy. (a) Image shows gestational age at 6 weeks with the characteristic ring sign, (b) a fetal heart rate of 155 beats per minute. (c) This structure (E) is separate from the ovary (O), which is located to the right of the ectopic gestational sac with a small follicle, and the uterus (U), which is seen to the left with fluid within the endometrial canal.

Figure 3

35-year-old female with positive pregnancy test presenting with pain later diagnosed with ectopic tubal pregnancy. (a-d) Transvaginal ultrasonography images reveal, (a) thick-walled gestational sac in the right adnexa with (b) a gestational age of approximately 7 weeks and (c) a fetal heart rate of approximately 154 beats per minute. (d) There is increased peripheral blood flow characteristic of the ring of fire, findings compatible with a live ectopic pregnancy.

Figure 4

33-year-old female presenting with pelvic pain later diagnosed with ectopic tubal pregnancy. (a-f) Transvaginal ultrasonography images reveal, (a) a thick-walled structure (black arrow) containing central fluid and (b) peripheral blood flow within the right adnexa adjacent to the right ovary (white arrow) but separate from it, (c and d) This structure measures approximately 3.1 × 2.3 × 3.0 cm, (e and f) There is a small amount of complex pelvic free fluid compatible with hemoperitoneum (white arrowhead).

Figure 5

24-year-old female presenting with pelvic pain and positive pregnancy test later diagnosed with ectopic interstitial pregnancy. (a-c) Transvaginal ultrasonography reveals, (a) an eccentrically located round ring-like mass (black arrow) in the left uterine fundus. Note the thin echogenic endometrial stripe (white arrow) which extends to the inner margin of this mass, (b) It is incompletely surrounded by myometrium and is compatible with a cornual pregnancy. This measures approximately 2.6 × 2.6 cm and (c) demonstrates peripheral blood flow on color Doppler interrogation.

Figure 6

28-year-old pregnant female presenting with pelvic pain later diagnosed with ectopic interstitial pregnancy. (a-e) Transvaginal ultrasound images reveal, (a) no gestational sac in the endometrial canal in this longitudinal midline image, (b) there is a gestational sac located eccentrically in the right cornua (white arrow) demonstrated on this transverse image, (c) There is blood flow to the periphery of the gestational sac that contains a yolk sac and fetal pole. (d) The gestational sac is approximately 6.8 mm from the edge of the uterus and (e) shows it is surrounded by a thin rim of myometrium measuring approximately 3.1 mm in thickness.

Figure 7

27-year-old female presenting with pelvic pain and vaginal bleeding and a positive pregnancy test, later diagnosed as ectopic interstitial pregnancy. Transvaginal pelvic ultrasonography images show - (a) a heterogeneous mass-like collection (white arrow) in the left adnexa, and in (b) a mass that does not demonstrate internal color Doppler flow representing blood clots and hemoperitoneum. There was no intrauterine pregnancy on evaluation, findings most compatible with a ruptured ectopic pregnancy.

Figure 8

40-year-old pregnant female presenting with pelvic pain later diagnosed with ectopic cervical pregnancy. (a-c) Transvaginal pelvic ultrasonography images show (a) a gestational sac (white arrow) in the lower uterine segment and superior cervix, (b) shows there is a fetus within the gestational sac, and (c) shows fetus with a crown–rump length measuring approximately 4.2 cm corresponding to a gestation of 11 weeks.

Figure 9

36-year-old pregnant female presenting with heavy vaginal bleeding for 3 days that slowed to occasional spotting. Patient had a history of two cesarean sections and was later diagnosed with ectopic cesarean pregnancy. (a-c) Transabdominal and transvaginal ultrasonography images reveal (a) a viable gestational sac at the site of previous cesarean scar (black arrow) with a gestational age of 8 weeks 5 days. (b and c) images show the gestational sac is in the lower uterine segment, just superior to the cervix and intimately related to the scar anteriorly (white arrows), MRI d) T2 axial view, (e) T2 sagital view and (f) contrast-enhanced images demonstrate trophoblastic tissue/developing placenta inferiorly with little or no surrounding myometrium (white arrow) confirming scar pregnancy There is some mass effect on the superior aspect of the urinary bladder on the right; however, it does not appear to invade the bladder wall.

Figure 10

26-year-old female presenting for a second opinion to confirm a heterotopic pregnancy. (a-d) Transvaginal ultrasonography images reveal (a) an intrauterine gestational sac with a fetal pole of gestational age 9 weeks 5 days. There is also a thick-walled ring-shaped structure in the right adnexa (white arrow) compatible with a tubal ectopic pregnancy, (b) image shows the ectopic gestational sac corresponds to 7 weeks 5 days and has a fetal pole, (c) reveals blood flow related to the ectopic pregnancy, (d) the power Doppler image demonstrates the characteristic ring of fire sign.

Figure 11

40-year-old female of advanced maternal age with a history of prior full-term cesarean delivery presented for assessment of pregnancy was later diagnosed with ectopic heterotopic pregnancy. (a-d) Transvaginal ultrasonography images reveal (a) a retroverted uterus with a gestational sac with a fetal pole and a positive heart rate in the cesarean scar (white arrow) with an estimated gestational age of 5 weeks 5 days, (b) image also shows a fundal gestational sac (black arrow) with a yolk sac, but no identifiable fetal pole with a gestational age of 5 weeks, and (c and d) Color Doppler images reveal blood flow related to the scar pregnancy.