Ectopic pregnancy: features at transvaginal sonography.

A retrospective review of the transvaginal sonograms of 50 women with laparoscopically confirmed ectopic pregnancy was performed to determine whether certain sonographic findings can be detected to confirm the diagnosis. Forty-seven of the 50 pregnancies were tubal. A tubal ring (a 1-3-cm mass consisting of a 2-4-mm concentric, echogenic rim of tissue surrounding a hypoechoic center) was seen in 23 of 34 (68%) ectopic pregnancies in which the fallopian tube had not ruptured, and the tubal ring could be distinguished from a corpus luteum cyst in most cases. Transvaginal sonography also depicted simple (n = 22) or particulate (bloody) (n = 13) peritoneal fluid associated with ectopic pregnancy. In each case in the series, at least one abnormal uterine, adnexal, or peritoneal finding was detected at transvaginal sonography. Because of its improved resolution of uterine and adnexal structures, transvaginal sonography is recommended as a means for detailed evaluation of patients suspected of having an ectopic pregnancy.