Isolated tubal torsion: a rare cause of pelvic pain at menarche. Sonographic and MR findings.

Isolated torsion of the fallopian tube is a rare clinical entity, especially in adolescents and at menarche. The diagnosis is essentially made at laparoscopy or at laparotomy because of nonspecific clinical signs. We present a case of isolated tubal torsion in a 12-year-old girl a few days after menarche, highlighting the sonographic and MR findings. Both techniques demonstrated the enlarged and tortuous fallopian tube with normal ovaries and uterus, but MR was also able to characterize contained blood and absent vascular supply. Although this condition is uncommon it should be considered as a cause of acute pelvic pain in adolescents because of the possibility of salvage surgery with early diagnosis. Sonography and MRI have a complementary role in this diagnosis.