Enhancement kinetics of normal ovaries on dynamic contrast-enhanced MR imaging.

Objective: The objective was to determine the enhancement kinetics of the normal ovaries in healthy women on dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging.

Method: Twenty-one women who had normal ovulatory cycles (volunteers; mean age=26.3 years, range=20-35), normal hormone profile, and apparently normal ovaries on ultrasonographic scan underwent DCE-MR imaging on a 1.5-T system (Philips Medical Systems, Gyroscan Intera, Best, The Netherlands) using a phased array pelvic coil. Sequential images with an imaging time of 14.4s per dynamic image were acquired before and after injection of a contrast bolus at 30s and at 1, 2, 3, 4, and 5 min. On postprocessing examination the following measurements were obtained for ovarian and muscle tissue: the signal intensity value per dynamic study, early phase enhancement rate, time to peak enhancement (Tp), and percentage of wash-out at the fifth minute were determined. Data of the ovaries and skeletal muscle were compared using Wilcoxon's rank sum test.

Results: Most of the mean values of the postcontrast signal intensity measurements, the mean values of the early phase enhancement rate, and the percentage of wash-out at the fifth minute were found to be significantly higher in ovary than in muscle (p<0.05). The mean values of Tp, on the other hand, were nonsignificantly lower in ovary than in muscle (p>0.05). On the examination of the mean signal intensity-time data graphics the ovary showed a tendency toward greater and quicker enhancement and wash-out.

Conclusion: In our opinion, DCE-MR imaging, which determines contrast enhancement such as wash-in and wash-out kinetics, can provide knowledge of ovarian vascularization. Thus, by using DCE-MR imaging, determination of these vascularization changes in various ovarian diseases may provide us with additional parameters in the diagnosis of and treatment strategies for ovarian diseases.