Usefulness of T2*-weighted MRI in the detection of adnexal torsion

BACKGROUND The usefulness of T2*-weighted (T2*W) imaging for the detection of adnexal torsion has yet to be determined. PURPOSE To assess the usefulness of T2*W imaging for detecting and differentiating adnexal torsion. MATERIAL AND METHODS Eight patients with eight ovaries with torsion and 44 patients with 72 ovaries without torsion were included in this study. All patients underwent 1.5-T magnetic resonance imaging (MRI) including T2*W images. The frequency and distribution of hypointensity on T2*W images were compared between ovaries with torsion and ovaries without torsion. RESULTS Hypointensity on T2*W images was significantly more frequent in ovaries with torsion than in ovaries without torsion (75% vs. 36%; P < 0.05). Among patients with hypointensity on T2*W images, the frequency of diffuse hypointensity was significantly higher in ovaries with torsion than in ovaries without torsion (83% vs. 0%; P < 0.01); whereas the frequency of focal hypointensity was significantly lower in ovaries with torsion than in ovaries without torsion (17% vs. 100%; P < 0.01). CONCLUSION The presence and distribution of hypointensity on T2*W images may play a supplementary role in the detection of adnexal torsion.