Diagnostic Twists and Turns: Spotting an Isolated Fallopian Tube Torsion

Isolated fallopian tube torsion (IFTT) is a rare form of adnexal torsion. A 2024 review described fewer than 150 cases over several decades. The clinical presentation of IFTT is highly variable and nonspecific, which may result in delayed diagnosis. Most patients present with acute unilateral abdominal pain with nausea and/or vomiting, while other patients may present with more gradual symptoms. Risk factors for IFTT include adnexal lesions, hydrosalpinx, previous pelvic surgery, and pelvic inflammatory disease. Ultrasound is particularly useful in identifying the imaging signs of IFTT, which include normal ovarian size and flow, a distended cylindrical structure that tapers to a "beak" adjacent to the ovary, thickened endosalpingeal folds resulting in a "cogwheel" appearance, and, lastly, a twisted vascular pedicle. We present an imaging-focused case in which the diagnosis of IFTT using ultrasound, following equivocal CT, resulted in prompt and confirmatory surgical management. Our goal is to raise awareness of IFTT as a possibility in females with abdominal pain and to discuss ultrasound characteristics that may increase clinical suspicion and diagnostic confidence. Prompt recognition and surgical management may prevent tubal necrosis and loss of fertility.