Endometrial blood flow analysis in postmenopausal women: can it help differentiate benign from malignant causes of endometrial thickening?

PURPOSE To determine if prominent vascularity and low pulsatility index (PI) and resistive index (RI) in endometrial arteries help differentiate carcinoma from benign lesions. MATERIALS AND METHODS Forty-five postmenopausal women with at least 8-mm-thick endometrium at endovaginal ultrasound (US) underwent color duplex Doppler endovaginal US of the endometrium. PI and RI values were recorded from arterial waveforms generated in areas of increased vascularity. RESULTS At color duplex Doppler endovaginal US, endometrial arterial flow was seen in 23 of 36 (64%) proved benign endometrial lesions. The range of PIs for benign lesions was 0.31-1.77 (mean, 0.72 +/- 0.33 [standard deviation]) and for RIs was 0.27-0.84 (mean, 0.48 +/- 0.13). Arterial vessels were seen in five of nine proved endometrial cancers (56%); the range of PIs was 0.42-1.17 (mean, 0.71 +/- 0.32) and for RIs was 0.34-0.69 (mean, 0.48 +/- 0.15). Differences in mean PI and RI for benign and malignant lesions were not significant. CONCLUSION Low-impedance arterial flow is observed in various diseases of the endometrium, and there is an overlap between the PI and RI of benign and malignant lesions.