Benign ovarian lesions with restricted diffusion

Abstract

Developments in magnetic resonance imaging have expanded its role in the assessment of the female pelvis, including the diagnosis of ovarian lesions. In this setting, diffusion-weighted imaging has proven its diagnostic value, which is particularly important in differentiating between benign and malignant ovarian tumors. In general, the latter show restricted diffusion, whereas the former do not. Exceptions include teratomas, endometriomas, hemorrhagic cysts, ovarian abscesses, ovarian infarction, and some benign stromal tumors. The aim of this review is to draw attention to benign ovarian lesions with restricted diffusion, with a special focus on diffusion-weighted imaging pearls and pitfalls.

Adnexal masses characterized on 3 tesla magnetic resonance imaging – added value of diffusion techniques

“…Neoplasms usually show diffusion restriction peripherally and abscesses centrally. 22,24 According to cystic degeneration, some adenofibromas also could be characterized by restriction of the water molecules. 22,25,26 In this study adnexal masses are classified based on their morphological appearance, similar to Foti et.…”

“…38 Endometriomas usually do not enhance after contrast administration but could have restricted diffusion. 11,22 Mixed ovarian masses containing both cystic and solid parts are always suspicious for malignant -surface epithelial tumors and metastases. The benign representative of this category is mature cystic teratoma.…”

“…They could represent with restricted diffusion in the areas with keratin and fat globules. 22,23 Serous and mucinous cystadenocarcinoma are the most common epithelial malignancies of the ovaries -50% and 10% of malignant lesions. 41 Mucinous tumors are larger, lobulated and may be hyperintense on T1WI in addition to the high protein concentration in mucoid material.…”

“… 21 Endometriomas as containing blood and hemosiderin can show diffusion restriction too. 21 , 22 Solid areas with similar changes can help the detection of malignant transformation. When it comes to an ovarian abscess, diffusion characteristics depend on the content – in more viscous one the signal intensity is higher on DWI and lower on ADC map.…”

“… 22 , 24 According to cystic degeneration, some adenofibromas also could be characterized by restriction of the water molecules. 22 , 25 , 26 …”