Background: We describe the ultrasonographic pattern of a pelvic echinococcus cyst, visualized using a vaginal probe and color Doppler.
Case: A 27-year-old woman presented with an asymptomatic right adnexal mass. Vaginal ultrasonography revealed a cyst in the posterior cul-de-sac, adjacent to the right ovary, with internal septae resembling a maze or an onion slice structure. Color Doppler revealed peripheral vascularization with a low resistance pattern (resistance index 0.6; pulsatility index 0.93). Benign cysts usually have a simple echogenic pattern. In contrast, ovarian carcinomas have a complex internal structure.
Conclusion: Ovarian echinococcus cysts may have a peculiar ultrasonographic pattern at high-frequency (7.5-MHz) vaginal ultrasonography. Such high-frequency ultrasonography can be a useful tool in the diagnosis of the disease.