Color Doppler sonography with contrast in the differentiation of ovarian tumors

Abstract

The objective of this study was to differentiate benign ovarian tumors from malignant ones before surgery using color and pulsed Doppler sonography, and to compare results obtained before and after use of contrast medium, thereby verifying whether contrast results in an improvement in the diagnostic sensitivity.METHODS: Sixty two women (mean age 49.9 years) with ovarian tumors were studied, 45 with benign and 17 with malignant tumors. All women underwent a transvaginal color Doppler ultrasonographic exam. A study of the arterial vascular flow was made in all tumor areas, as well as an impedance evaluation of arterial vascular flow using the resistance index.RESULT: Localization of the vessels in the tumor revealed a greater proportion of malignant tumors with detectable internal vascular flows (64%) than benign tumors with such flows (22%). There was a considerable overlap of these findings. The use of contrast identified a greater number of vessels with confirmation in the totality of tumors, but did not improve the Doppler capacity in tumoral differentiation. Malignant tumors presented lower values of resistance index than the benign ones, whether or not contrast was used. The cutoff value for resistance index that better maximized the Doppler sensitivity and specificity was 0.55. Through this value, an increase of the sensitivity after contrast use was obtained, varying from 47% to 82%, while specificity remained statistically unchanged.CONCLUSION: Although the injection of a microbubble agent improved the sensitivity of the method detecting vascularization of tumors, a positive finding for vascularization by this method was not clinically useful in the differentiation of benign and malignant ovarian tumors. Considerable evidence indicates that neovascularization is responsible for the tumoral growth and invasion 1 . Ultrasonography with color and pulsed Doppler provides dynamic information concerning the distribution of tumor vessels and their impedance value through the determination of resistance (RI) and pulsatility (PI) indices. Preliminary data suggests that it is possible to detect vascular changes associated with angiogenesis in early ovarian cancer through this technique 2 . A possible explanation for these changes is that the new blood vessels present in the carcinomas have limited muscular tonus due to the absence of the medial layer and that together with numerous existing arteriovenous shunts, they would be responsible for the low impedance registered by the RI and PI indices. However, this method presents some restrictions associated with the inaccessibility to the small caliber vessels, thus demonstrating low sensitivity for the intended purpose 3 . The advent of echo-enhancing substances for endovenous use, according to experiences in other organs 4 , would allow better visibility of these vessels, thereby helping in the differentiation of the neoplastic process. 186REV. HOSP. CLÍN. FAC. MED. S. PAULO 58(4): [185][186][187][188][189][190][191][192] 2003 Color Doppler sonography with contrast...

Accuracy of ultrasonography and color Doppler in diagnosis of ovarian masses and its correlation with histopathological findings

“…9 The color doppler allows to examine the flow of the pelvic organs investigated by ultrasound. [10][11][12] Combining the advantages of color with high resolution image provides a proper and immediate visualization of the pelvic vessels. With the aid of the color doppler all the vessels are identified.…”