title: Adnexal ring sign and hemoperitoneum caused by hemorrhagic ovarian cyst: pitfall in the sonographic diagnosis of ectopic pregnancy.
authors.affiliation: Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: B S
authors.initials: BS
authors.lastname: Hertzberg
authors.forename: M A
authors.initials: MA
authors.lastname: Kliewer
authors.forename: J D
authors.initials: JD
authors.lastname: Bowie
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D019160:Endosonography; D005260:Female; D006465:Hemoperitoneum / Q000000981:diagnostic imaging*; D006801:Humans; D010535:Laparoscopy; D010048:Ovarian Cysts / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000000981:diagnostic imaging; D011271:Pregnancy, Ectopic / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity