Induced fluid movement within a giant ovarian cyst demonstrated by echo-planar imaging.

Over 50% of ovarian tumours are of epithelial origin occurring as solid carcinomas and mucinous or serous cysts, the majority of which can be readily categorized as benign or malignant. However, approximately onefifth of the cysts, whilst showing some histological feature of malignancy, lack evidence of stromal invasion and are therefore reported as borderline malignancy. Serous cystadenomas may be unilocular or multilocular and vary in size from a few centimetres to enormous dimensions where they come to occupy most of the pelvis and abdominal cavity. In approximately 50% of cases the tumours are bilateral. Some have intracystic papillary ingrowths or solid areas in one or more loculi, and invasion of the cyst wall with tumour extension onto the serosal surface indicates the transition from a cystadenoma to a cystadenocarcinoma. A giant serous cyst of the ovary has been imaged by echo-planar imaging (EPI) (Mansfield, 1977) and the features observed compared with the operative and pathological findings. T...