Discriminative MRI features of fallopian tube masses.

Fallopian tube disease, both acute and chronic, is a common cause of a sonographically indeterminate adnexal mass and may mimic ovarian cancer. Magnetic resonance imaging (MRI) is now widely used as a problem-solving tool in these circumstances. The purpose of this review is to provide the discriminative MRI features of Fallopian tube masses and illustrate the key signs that establish their origin and nature. Familiarity with these characteristics enables distinction of tubal disease from malignant adnexal disease with major impact on management. On MRI, Fallopian tube disease exhibits features that parallel the classical sonographic findings, but which can be more reliably recognized due to improved contrast and spatial resolution, multiplanar capacity, effective field of view, and tissue characterization. Recognition of these characteristic morphological features and specific MRI signal patterns are key to a specific diagnosis. The anatomical and histopathological basis of these MRI signs is emphasized, covering also the differential diagnosis and pitfalls. Two new signs, "synechiae" and "amorphous shading", are also described that have not been well described previously in MRI of tubal disease.