Aims &objectives: 1) MRI criteria for accurate diagnosis of adnexal lesions 2) Differentiating MR features for benign from suspicious malignant lesions. 3) Defining the potentiality of DWI in the characterization of complex adenexalmasses.

Summary: The final diagnosis of the 56 patients included in the study was based on biopsy and histopathological verification in 37 patients (58.7%). The other patients were diagnosed by the characteristic MRI features, and follow up by monitoring clinical response to medical treatment (41.2%)  The 6 patients diagnosed to have torsion of pedicle were later proven surgically. All the patients diagnosed with benign and malignant ovarian neoplasms were histopathologically proven. All the patients having tuberculoustubo-ovarian abcesses were pathologically proven. All the patients diagnosed as borderline ovarian neoplasms were pathologically proven. All the patients with endometriomas showed characteristic MRI features. All the patients with extraovarian pathologies were improving on medical treatment.  Followup in majority of cases did not reveal any recurrence/complications.

Conclusions: Sonographically indeterminate adenexal masses of solid or complex cystic content benefit from further evaluation with MRI, which is highly accurate for identifying the origin of a mass and characterising its tissue content, obviating surgery in many cases. The role of DWI in distinguishing between benign and malignant cystic tumors is limited and the ADC values calculated from the DWI will add useful information to the differential diagnosis especially ovarian cystic masses. An adenexal mass with no restricted diffusion usually is a benign lesion, however information derived from images obtained with other sequences will be helpful. Pitfalls were noted in some Ovarian cystic lesions with water diffusion restriction in cases of Abscess,mature cystic teratomas, endometriotic cysts. All malignant ovarian lesions are always restricted in the DWI with ADC values less than 0.5. DWI provides supplemental information in patients with gynecological disorders and could easily be incorporated into standard clinical protocols utilizing MRI, corroborating with histopathological findings.

Keywords: Adnexal masses, Indeterminate lesions, Diffusion weighted Imaging, Magnetic Resonance Imaging.