fallopian tube torsion

WHAT IS FALLOPIAN TUBE TORSION?

Twisting of the fallopian tube on itself -- similar to closed loop bowel obstruction

Ovarian torsion is more of an end tube twist, Fallopian tube torsion is proximal to ovarian torsion

Much more rare cause of LQ abd pain/pelvic pain than ovarian torsion

                Prevalence: one in 1.5 million women

                Population at risk: pre-menopausal women, 80% are <50 yo

Risk factors: Most commonly benign etiology (89%)

                Intrinsic factors:  long mesosalpinx, tortuous dilated tube (hydro- or hemato-salpinx), tubal mass, tubal ligation, PID, abnormal peristalsis/periovulatory spasm

                Extrinsic factors:  adhesions, adnexal venous congestion, adjacent ovarian or paraovarian masses, uterine masses, gravid uterus, trauma, sudden body position changes (Sellheim theory)

Proposed mechanism: Mechanical obstruction of adnexal veins/lymphatics --> pelvic congestion/edema --> enlargement of fimbrial end --> partial/complete torsion of tube

                Since vascular supply to adnexa comes from ovarian + uterine vessels --> can get isolated tubal necrosis w/o ovarian vascular compromise

DDx: ovarian torsion, ruptured ovarian cyst, PID, ectopic, appy, urolithiasis, cystitis, SBO/perf

Difficult diagnosis -- non-specific findings, pain is only universal feature

Clinical presentation

Sudden onset lower quadrant abdominal pain / pelvic pain

                May be more intermittent than ovarian torsion (53% had previous attacks of undx’d abd pain)

Slightly more common on the right (3:2 R:L)

Labs: Leukocytosis is mild, and late finding (>24 hrs after onset) -- tube likely unsalvageable

Ultrasound findings

Normal ovaries + uterus with normal blood flow

Free pelvic fluid

Dilated adnexal tubular structure that flares at one end, with thickened echogenic walls, suspicious for hydrosalpinx

A beaked, tapering appearance of the tube, with its vertex pointing toward the affected adnexa

Internal debris/convoluted echogenic mass, which may represent thickened torsed tube

Difficult to visualize vascular compromise of tubal wall

CT findings

Adnexal mass, twisted appearance to fallopian tube, dilated tube >15 mm, thickened enhancing tubal wall, luminal attenuation >50 H c/w hemorrhage

Free pelvic fluid, peritubular fat stranding, enhancement + thickening of broad ligament, regional ileus

Treatment options

Surgical detorsion, salpingotomy

Salpingectomy frequently performed 2/2 irreversible damage

Submitted by S. Eucker.

Reference(s): Gross, M et al, “Isolated Fallopian Tube Torsion: A Rare Twist on a Common Theme”, AJR 2005; 185: 1590-1592.  (Also the reference for the images); Ho, P et al, “Isolated Torsion Of The Fallopian Tube: A Rare Diagnosis In An Adolescent Without Sexual Experience” Taiwan J Obstet Gynecol 2008; 47(2):235-237. Ferrera, P et al, “Torsion of the Fallopian Tube”, Am J Emerg Med 1995; 13:312-314. Weir, CD and Brown, S, “Torsion of the Normal Fallopian Tube in a Premenarcheal Girl: A Case Report”, J Pediatr Surg 1990; 25(6):685-686.