TRANSVAGINAL SONOGRAPHIC FEATURES IN DIAGNOSIS OF ECTOPIC PREGNANCY

OBJECTIVES: To evaluate the efficacy of pelvic transvaginal sonography (TVS) in patients with clinical presentation of extrauterine pregnanc y (EUP) and positive beta-hCG. METHODS: Three hundred and twenty-one p atients with clinical suspicion of EUP were subjected to TVS at Mahara j Nakorn Chiang Mai Hospital, The criteria for entry to the study were (1) clinical suspicion of EUP, with stable hemodynamic condition, (2) correct final diagnosis must be known, (3) serum beta-hCG must be det ermined by assay sensitivity of 10 mIU/ml (4) TVS was examined by the same sonographer. Frequencies of each TVS feature in EUP and IUP were determined. Among the patients with positive beta-hCG and empty uterus , the accuracy indices of various TVS features in predicting EUP were calculated. RESULTS: Patients with measurable beta-hCG were divided in to two main groups, namely those with demonstrable typical intrauterin e gestational sac (52/201), and those without (149/201). None of the s ubjects in the first group had EUP. Among the latter group of patients , with empty uterus, TVS signs could be further divided into 3 subgrou ps. (1) Direct sign, clear evidence of extrauterine gestational sac. T his group had positive predictive value 100%, but low sensitivity (26% ). (2) Indirect signs of EUP, i.e. adnexal mass and pelvic fluid, espe cially echogenic fluid. Echogenic fluid, adnexal mass and their combin ation had positive predictive value for EUP 92.3%, 92.8% and 95.0%, re spectively. Complex adnexal mass gave the highest sensitivity (85.7%). (3) No positive sign on TVS, which is very unlikely to be EUP, and wa s found in only 2.8% of EUP. CONCLUSIONS: The results of this study in dicate that TVS can help to facilitate the diagnosis of EUP in most ca ses. EUP can be confidently diagnosed by demonstration of adnexal ring , and excluded by visualization of intrauterine sac. Complex adnexal m ass and echogenic fluid are extremely helpful in making the diagnosis.