Fig. 21

Sagittal T2-weighted MR image of a 22-year-old female with mature cystic teratoma (a). A hyperintense structure (arrows) with an obvious chemical shift artefact lying in the interface of the fat-fluid level is seen in a cystic mass. It is consistent with matted hair and keratinoid material in the macroscopic specimen (b). Note the Rokitansky nodule at the posterior wall with hyperintense parts that were proven to be fat and linear hair shafts (arrowhead) arising from the nodule in the T2-weighted image. Cut-section photograph of the Rokitansky nodule is shown in Fig. 25d