Fallopian tube torsion

A fallopian tube torsion is a type of adnexal torsion and usually occurs in association with an ovarian torsion (when it is then termed a tubo-ovarian torsion). An isolated fallopian tube torsion is rare but can occur. 

Pathology

An isolated tubal torsion can occur as a late complication of tubal ligation ^1,2.

Other risk factors for an isolated fallopian tube torsion include ^3,8 

• intrinsic factors

  • pelvic inflammatory disease (PID)

  • anatomical abnormalities

    • hydrosalpinx

    • hematosalpinx: can also be a consequence

    • long mesosalpinx 

  • physiological abnormalities

    • tubal spasm

    • hypermotility of tube

  • tubal neoplasm

• extrinsic factors 

  • adhesions

  • adnexal venous congestion

  • adjacent ovarian or paraovarian masses (e.g. paraovarian cysts)

  • uterine masses

  • gravid uterus

Location

There is a well-recognized right-sided predilection ⁹

Radiographic features

Ultrasound

Reported sonographic findings include ^3,5

• a normal-appearing uterus and ovaries with normal flow

• free fluid

• a dilated tube with thickened, echogenic walls and internal debris 

• a convoluted echogenic mass thought to represent a thickened, torsed tube

• sonographic whirlpool sign: described as a relatively specific sign of tubal torsion ⁷

CT

Reported primary CT findings of isolated tubal torsion include ^3,4

• an adnexal mass

• twisted appearance to the fallopian tube with dilated tube greater than 15 mm

• thickened and enhancing tubal wall and luminal CT attenuation greater than 50 HU, compatible with hemorrhage

Secondary signs include

• free intrapelvic fluid

• peritubular fat stranding

• enhancement and thickening of the broad ligament

• regional ileus