ENDOMETRIAL COLOR-FLOW IMAGE-DIRECTED DOPPLER IMAGING - NEGATIVE PREDICTIVE VALUE FOR EXCLUDING ECTOPIC PREGNANCY

Purpose: Visualization of an intrauterine pregnancy with transvaginal ultrasound virtually excludes an ectopic pregnancy. However, findings that might lower patients' risk for ectopic pregnancy have not been ex tensively investigated. We prospectively performed transvaginal color flow/image-directed Doppler imaging of the endometrium to determine th e predictive value of endometrial blood flow for excluding ectopic pre gnancy. Materials and Methods: From April 1994 to August 1995, 211 con secutive women underwent transvaginal ultrasound examinations to exclu de an ectopic pregnancy. Color flow/image-directed Doppler imaging of the endometrium was performed on each patient. Flow was considered to be present only if a Doppler signal could be obtained with the cursor located completely within the endometrium. All Doppler imaging paramet ers were optimized for each patient. Resistive indices were obtained i f arterial signal was present, and receiver operator characteristic cu rves were constructed for RI and peak systolic velocity. Findings were correlated with surgical and pathology results. Results: Of 211 total patients, there were 55 ectopic pregnancies (52 diagnosed for a sensi tivity of 95%), 89 incomplete spontaneous abortions, 40 completed spon taneous abortions, and 27 intrauterine pregnancies. Of 55 ectopic preg nancies diagnosed with real time imaging, 9 had areas of endometrial b lood flow (6 venous, 3 arterial), and 46 did not. Of the 156 patients that did not have an ectopic pregnancy, 107 had arterial blood flow wi thin the endometrium, and 49 had no flow. Using only cases with arteri al signal, the negative predictive value of endometrial blood flow for excluding an ectopic pregnancy was 97% (107/107 + 3). The optimal cut off values (5% false-positive rate) for peak systolic velocity and ref ractive index (RI) were 15 cm/s and 0.55. Conclusions: Arterial blood flow within the endometrium lowers the risk for ectopic pregnancy even when other findings that might indicate a high risk are present. Veno us flow within the endometrium does not exclude an ectopic pregnancy. (C) 1997 John Wiley & Sons, Inc.