Figure 1: (a) Sagittal T2-weighted MR image shows a large solid and cystic ovarian tumor of 17 cm at maximum diameter and small amount of ascites. The tumor had arisen from the left ovary, and the margin was smooth. Uterus was normal size but accompanied with slightly thickened endometrium and distinct zonal anatomy. (b) Axial T1-weighted MR image revealed a mature cystic teratoma of 4 cm in a diameter which included fat component inside the tumor at the left anterior side.