The Utility of Ultrasound Elastography in Differentiation of Endometriomas and Hemorrhagic Ovarian Cysts

Abstract

To investigate the feasibility of acoustic radiation force impulse imaging in differentiation of endometriomas and hemorrhagic ovarian cysts. We evaluated 84 ovarian cysts with high internal echogenicity diagnosed in 70 consecutive women. We excluded simple cysts and hemorrhagic cysts containing septations or mural nodules with detectable flow on Doppler ultrasonography. We obtained the elastographic shear wave velocity (SWV) value of the cysts that could be endometriomas or hemorrhagic ovarian cysts. Among the 78 ovarian cysts in 70 women without any septation or mural nodule, there were 42 endometriomas and 36 hemorrhagic ovarian cysts. Analysis of median SWV values of the ovarian cysts showed that the endometriomas had considerably higher levels of stiffness compared to the hemorrhagic ovarian cysts [median SWV 4.20 +/- 0.42 vs 2.54 +/- 1.04 m/s, p < 0.001]. A SWV cutoff value greater than 3.81 m/s yielded sensitivity and specificity values of 82.1 and 79.2 % respectively, for differentiation of endometriomas from hemorrhagic ovarian cysts. Sonoelastography is a novel imaging technique that enables us to evaluate the stiffness of adnexal lesions. The accurate discrimination of endometriomas and hemorrhagic ovarian cysts is important for avoiding unnecessary surgical procedures. ARFI imaging has a high sensitivity and specificity for distinguishing endometrioma from hemorrhagic ovarian cysts.