Adnexal torsion: Magnetic resonance findings in the viable adnexa with emphasis on stromal ovarian appearance

Purpose: To evaluate ultrasound (US) and magnetic resonance (MR) findings in the viable twisted adnexa. Materials and Methods: Ten patients underwent US and MR studies before surgical detorsion. Corrected cross-sectional area of the ovary was defined as cross-sectional area minus areas of cysts and follicles superior to 1 cm. On T2-weighted images, signal intensity of the stroma was graded as type 1 when it was equal to that of urine and type 2 when it was less than that of urine but markedly more than the contralateral side. Results: The tube was twisted in six cases and the ovary in nine cases. All adnexa were viable. The largest ovarian cross-sectional area and the largest corrected ovarian cross-sectional area of the twisted ovary were significantly larger than those of the contralateral ovary (P = 0.043 for US; P = 0.012 and 0.017, respectively, for MR). These ovaries contained types 1 and 2 hyperintensity in six cases and only type 2 hyperintensity in three cases. Tubal thickening was seen on MR in five cases. Conclusion: Tubal thickening, enlargement of ovarian stroma as reflected by the corrected cross-sectional area, and hyperintensity of this stroma on T2-weighted images probably related to edema were useful findings in these viable torsions.