Complex, predominantly cystic masses Complex, predominantly cystic masses. A: Complex mass with solid areas and high-impedance flow (pulsatility index [PI] = 2.1). This was a dermoid cyst. B: Septated cystic mass with an area of low-impedance flow (PI = 0.5) in a thick septum. A mucinous cystadenocarcinoma was found at surgery. At histology, an abnormally dilated tumoral vessel was found within the septation. C: Complex mass with irregular cystic areas with high-impedance, high-velocity flow. This was a hemorrhagic corpus luteum cyst. D, E: A complex mass with cystic areas with high-velocity (maximum systolic velocity = 18 cm/s), low-impedance (PI = 0.49) flow. This represented a tubo-ovarian abscess. Low-impedance flow was related to vasodilation observed in the initial inflammatory phase. F: Septated mass with low-impedance (PI = 0.8), low-velocity (maximum systolic velocity = 10 cm/s) flow within a papillary excrescence. This was ovarian cancer. G: Septated mass with high-impedance (PI = 1.4), low-velocity (maximum systolic velocity = 9 cm/s) flow was found to be a benign mucinous cystadenoma. H: Complex mass with irregular solid areas suspicious for cancer. No flow was seen within the solid areas, however. This was a large endometrioma that contained focal areas of clot. Source: COLOR DOPPLER SONOGRAPHY OF PELVIC MASSES, Sonography in Obstetrics and Gynecology: Principles & Practice, 7e Citation: Fleischer AC, Toy EC, Lee W, Manning FA, Romero RJ. Sonography in Obstetrics and Gynecology: Principles & Practice, 7e; 2014 Available at: http://obgyn.mhmedical.com/DownloadImage.aspx?image=/data/books/1414/fle_ch32_f006d.png&sec=76395922&BookID=1414&ChapterSecID=76395876&imagename= Accessed: October 15, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved