Isolated Fallopian Tube Torsion: A Unique Ultrasound Identity or a Serial Copycat?

To report the preoperative ultrasound (US) signs of isolated fallopian tube torsion in surgically verified cases and to estimate whether preoperative US detection of this condition can be improved.

The charts of 27 women with a surgical diagnosis of isolated fallopian tube torsion at a tertiary medical center from 2005 to 2016 were retrospectively reviewed. Data were collected from the electronic database of the US unit and compared with the surgical findings.

Isolated fallopian tube torsion was correctly diagnosed by US before surgery in 8 of the 27 women (29.6%). In the remainder, the US signs were attributed to torsion of the ovary or the entire adnexa (n = 13), or no torsion was suspected (n = 6). Fallopian tube edema was listed as a US finding in 7 patients, of whom 5 had a correct diagnosis of isolated fallopian tube torsion. The presence of a paraovarian cyst concomitant with normal-appearing ovaries was assumed by US in 5 of the 8 cases that were accurately diagnosed as isolated fallopian tube torsion. The most misinterpreted US finding was an ovarian cyst (suspected in 10 patients and verified at surgery in 2). Absence of blood flow was described in 12 women, of whom 5 had an accurate diagnosis of isolated fallopian tube torsion. Six of the patients with a correct US diagnosis were adults (37.5% of total adults), and 2 were adolescents (18.2% of total adolescents).

The US diagnosis of isolated fallopian tube torsion is challenging. A high index of suspicion is necessary to improve its detection, especially when there are possible US signs of torsion in the presence of a normal-appearing ovary.