[Isolated fallopian tubal torsion; rare or overlooked?]

Isolated fallopian tubal torsion (IFTT) is a rare cause of lower abdominal pain. It's difficult to diagnose preoperatively due to non-specific clinical symptoms. Furthermore, IFTT is often not considered in the differential diagnosis. Prompt diagnosis is critical, to prevent progression of symptoms and to maintain fertility; therefore, this article discusses diagnostic pitfalls and reports on key imaging features of IFTT that may facilitate preoperative diagnosis. IFTT should be suspected in a female patient with acute lower abdominal pain and a unilateral pelvic mass close to a normal ipsilateral ovary; there may be a history of prior tubal ligation. Specific imaging findings include the sonographic 'whirlpool sign' and absent flow during colour Doppler ultrasound. CT is often performed when the diagnosis remains unclear, but has no clinical consequences. IFTT requires emergency surgical treatment; detorsion without resection can be considered in women who would like to retain potential future fertility, but salpingectomy is often inevitable due to necrosis.