Case of the Week 29 2015

Answer: Tubal ectopic pregnancy

Case Discussion:

Transvaginal ultrasound images show right tubal ectopic pregnancy, containing a yolk sac and a living embryo. Additionally, there is fluid in the pouch of Douglas and thickened endometrium.

Ectopic pregnancy is the implantation of a fertilized egg outside of the uterine cavity. Clinical presentation is frequently with abdominal pain, amenorrhea, and vaginal bleeding. If unrecognized hemorrhage can be life threatening.

Location of ectopic pregnancy
• tubal ectopic: 93-97%
 ampullary ectopic pregnancy (most common)
 isthmal ectopic pregnancy
 fimbrial ectopic pregnancy
 interstitial ectopic/cornual ectopic pregnancy (rare)
• atypical ectopic pregnancies
 ovarian ectopic pregnancy
 cervical ectopic pregnancy
 scar ectopic pregnancy
 abdominal ectopic pregnancy

Ultrasound features
• Adnexal mass: the presence of an adnexal mass is more specific for an ectopic pregnancy when it has a yolk sac or a living embryo.
• Haematosalpinx
• Tubal echogenic ring: concentric, echogenic rim of tissue surrounding a hypoechoic center.
• Ring of fire sign on Doppler US
• Haemoperitoneum, especially in cases of rupture

References:
1. Lin EP, Bhatt S, Dogra VS. Diagnostic clues to ectopic pregnancy. Radiographics. 2008;28(6): 1661-71.
2. Subramanyam BR, Raghavendra BN, Balthazar EJ et-al. Hematosalpinx in tubal pregnancy: sonographic-pathologic correlation. AJR Am J Roentgenol. 1983;141(2): 361-5.