Presentation
Acute severe lower abdominal pain.
Patient Data
Contrast-enhanced MRI study shows large posterior pelvic cystic lesion centered on the Douglas Pouch, elicits intermediate signal in T1 and high signal in T2 with a mural based small polypoidal component of low signal intensity in all pulse sequences. The left ovary appears enlarged and edematous with diffuse parenchymal hyperintensity in T2WI and heterogeneous enhancement in the post-contrast study. Twisted left ovarian vascular pedicle giving "Whirlpool sign". Twisted appearance of the fallopian tube with associated tubal dilatation and wall thickening.
The green arrows point to the twisted left fallopian tube, the red arrow points to the twisted left ovarian vascular pedicle, the yellow arrow points to the enlarged edematous left ovary, and the blue arrow points to the dilated thickened-wall left fallopian tube.
Case Discussion
Urgent laparoscopy was done that confirms a large pelvic cyst closely related to the left fallopian tube that appears torsed with multiple twists however no evidence of tubal necrosis. Partial twist of the left ovarian vascular pedicle with enlarged edematous ovary, however still viable with no necrosis. Cystectomy and untwisting were performed. The histopathological assessment revealed a hemorrhagic mesothelial cyst
Teaching points:
- Fallopian tube torsion is usually associated with ovarian torsion and should not be overlooked on imaging. Isolated tubal torsion could also occur but rare
- Large masses and cysts predispose to ovarian and tubal torsion
- Ovarian torsion may be incomplete with venous drainage compromise and preserved arterial supply
- Twisted appearance and whirlpool sign are important clues for suspicious of adnexal torsion