الفهرس | Only 14 pages are availabe for public view |
Abstract There is no gold standard for the diagnosis of a benign versus malignant ovariantumor prior to surgery, especially when the tumor has both solid and cystic components. Predictors of ovarian malignancies include lesion size (>6 cm), thickness of the walls andsepta (>3 mm), and the detection of internal structures including papillary projections,nodularity, various degrees of solid components, necrosis, haemorrhage, or regions ofstriking enhancement following administration of contrast medium . But these imaging parameters have been found to overlap for benign and malignant ovarian lesions. Therefore, as proposed by Katayama and homassin-Naggara et al. , the above mentioned parameters are not always the most accurate predictors of ovarian malignancies. Thus, the addition of DWI to conventional Tl-weighted and T2-weighted MRI protocols may increase the accuracy of distinguishing ovarian benign and malignant tumors with solid components. The advantage of using DWI include also that it is a non-invasive technique, it does not cause a patient significant discomfort, and it does not require exposure to ionizing radiation or injection of contrast materials Infact the majority of malignant ovarian tumors, mature cystic teratomas, and almosthalf of the endometriomas exhibited abnormal signal intensity on DWI, whereas mostfibromas and other benign lesions did not. Therefore the solid component within thecomplex adnexal mass with low signal intensity on T2 weighted and DWI sequences are invariably benign . However, the assessment of morphology and contrastenhancementyielded correct diagnosis. In conclusion, DWI and the corresponding measurements of ADC values, could integrate the morphological and dynamic findings in discriminating malignant from benign ovarian masses. |