A dermoid cyst showing a Rokitansky nodule or dermoid plug - cystic adnexal mass with some mural components. Most lesions are unilocular. It often contains adipose, hair and/or sebaceous components, if contains calcific or dental components there will be posterior shadowing. Colour Doppler: no internal vascularity - A dermoid cyst may contain one or more Rokitanski nodules - Sometimes sedimentation occurs producing a fluid-fluid level.
Bilateral dermoid cysts - The echoic “white ball” aspect may occupy sometimes the entire cystic cavity. The histopathologic exam of the entirely echoic dermoid cysts shows a content containing mainly hair, fat and sebaceous material. Not so often within the dermoid cyst may be seen echoic spheres produced by fat material conglomerates that fl oat inside the cyst.
The tip of the iceberg sign refers to one of the characteristic appearances of an ovarian dermoid cyst. The highly echogenic cyst contents of sebum and hair cause posterior attenuation of sound, so that only the superficial part of the cyst is seen.
The dot-dash pattern (dermoid mesh) is one of the characteristic sonographic appearances of an ovarian dermoid cyst. It refers to the short and long echogenic lines which are often seen within a dermoid cyst and are due to the presence of hair.
Ovarian dermoid cyst with Rokitansky nodule -Radiopaedia.org - Whenever the size exceeds 10 cm, soft tissue plugs and cauliflower appearance with irregular borders are seen or internal vascularity was noticed malignant transformation should be suspected.