Cystic ovarian teratomas: the sonographic appearance of the dermoid plug.

The sonographic and pathological appearance of 13 cystic ovarian teratomas was reviewed. Twelve contained at least one mural nodule (dermoid plug) and one was completely cystic. Altogether there were 15 dermoid plugs, varying in consistency from homogeneous solid tissue to cystic. More than half were associated with hair and/or calcium. The nodules were round, ranged from 1 1/2 to 4 cm, formed an acute angle with the wall of the cyst, and tended to be entirely or predominantly hyperechoic. The authors suggest that most cystic teratomas contain dermoid plugs having a characteristic shape and hyperechoic pattern.