Sonographic appearance of corpus luteum in early pregnance in gray-scale,color and pulsed Doppler ultrasonography / 中华超声影像学杂志

ABSTRACT

Objective To understand the gray-scale, color and pulsed Doppler sonographic feature of the corpus luteum during the early trimester of pregnancy. Methods The ovaries of 174 patients with intrauterine gestations between 5 to 9 weeks' menstrual age were examined with transvaginal sonography. Size, sonographic appearance, color Doppler feature, resistance index, peak systolic velocity of the corpus letuem were recorded. Results The corpus luteum was identified in 169 of 174 patients(97.1%) . The mean diameter was ( 1.7 ? 0.8 ) cm. The gray-scale appearances were classified into four typesa thin wall cyst(47 patients, 27.8 %), a thick wall simple cyst(45 patients, 26.6 %), a round hypoechoic structure(43 patients, 25.4 %), a thin-walled cyst containing internal debris (34 patients, 20.1 %). Color blood flow was visualized with color Doppler imaging in 92.3 %(156/169). Color Doppler imaging typically revealed a circumferential rim surrounding part or all of the corpus luteum. Low-resistance blood flow was seen with pulsed Doppler, with a mean resistance index of 0.41?0.10 . Conclusions The corpus lutuem in early pregnancy is identified with transvaginal sonography and has different sonographic appearances. It is important to recognize the various appearances of the corpus lutuem to avoidits confusion with true ovarian abnormalities and ectopic pregnancy.