Assessment of cyclic changes of microvessels in ovine ovaries using Sonovue contrast-enhanced ultrasound

Our objective was to detect variations of ovarian vascularization that occur in the estrus cycle of the ewe using an IV contrast agent. Five ewes were investigated using contrast-enhanced power Doppler after Sonovue injection at day 0, 3, 5, 10 and 13 of the cycle in two successive estrus cycles. Transvaginal ultrasound monitoring of each ewe was performed after a dose of Sonovue. Parameters derived from the time-intensity curves were compared. Quantification of the enhancement and wash-in period parameters changed significantly between ovaries and between the follicular and luteal periods of the cycle. Uptake time, wash-out time, total time of enhancement and area under the curve were the parameters with the smallest variation between ovaries. Wash-out time and area under the curve are two contrast parameters that did not change with cyclic changes. Thus, using these parameters in premenopausal women will allow more accurate detection of vascular modifications that may be associated with ovarian cancer.