Presentation
Cystic ovarian teratoma for 2 years, for follow up
Patient Data















The right ovarian cystic lesion is still noted with fat-fluid level and a central nodule and smooth outer contours, measuring 12 x 9 cm.
Posterior wall fundal subserous leiomyoma, measuring 7.7 cm, showing low T2 signal with no degeneration.

The similarity of such form of mature cystic teratoma of the ovary to the Poké ball. The inner ball "Rokitansky nodule" is seen at the centre, floating at the fat-fluid level which on T1 fat sat, the upper fat-layer appears darker like the red upper colour of the Poké ball in contrast to the white lower colour.
Case Discussion
Ovarian mature cystic teratoma is a common ovarian neoplasm with rich fat content and is easily confirmed on MRI.
A Rokitansky nodule is seen as a round structure protruding into the cyst lumen. The appearance of dermoid cyst is such case resembles the appearance of "Poké ball" made by the Rokitansky nodule and the fat fluid level, that usually described as "floating ball sign". This appearance is characteristic for mature cystic teratoma of the ovary.