Unusual etiology of epigastric pain

Imaging Features of Uncommon Entities That Manifest with Torsion

Torsion is the twisting of an object along the axis, and various structures (organs and tumors) in the body can twist. Torsion causes initial lymphatic and venous outflow obstruction, leading to congestive edema, enlargement, venous hemorrhagic infarction, and surrounding edema. It can also cause subsequent arterial obstruction depending on the degree of torsion, leading to ischemia, infarction, necrosis, gangrene, and surrounding inflammation. Therefore, in several cases of torsion, immediate surgical intervention is required to improve blood flow and prevent serious complications. Clinical manifestations of torsion are often nonspecific and can affect individuals of varying ages and sex. Imaging plays an important role in the early diagnosis and management of torsion. Multiple imaging modalities, including US, radiography, CT, and MRI, are used to evaluate torsion, and each modality has its specific characteristics. The imaging findings reflect the pathophysiologic mechanism: a twisted pedicle (whirlpool sign), enlargement of the torsed structures, reduced blood flow, internal heterogeneity, and surrounding reactive changes. The whirlpool sign is a definitive characteristic of torsion. In some cases, despite poor internal enhancement, capsular enhancement is observed on contrast-enhanced CT and MR images and is considered to be associated with preserved capsular arterial flow or capsular neovascularization due to inflammation. Radiologists should be familiar with the pathophysiologic mechanisms, clinical characteristics, and imaging characteristics of torsion in various structures in the body. Since other articles about common organ torsions already exist, the authors of this article focus on the uncommon entities that manifest with torsion. ©RSNA, 2024.

Benign nodular hyperplasia of the liver-pedunculated form: diagnostic contributions of ultrasonography and consideration of exophytic liver tumors

Focal nodular hyperplasia (FNH) is an asymptomatic benign liver tumor that may be detected accidentally during an abdominal ultrasound examination; it is associated with unspecific complaints, sometimes painful. Diagnosis can be precise using imaging techniques like ultrasonography. The diagnostic criteria are represented by the spatial display of the tumoral vessels and their hemodynamic characteristics. Sometimes differential diagnostic issues occur with other benign or malignant liver tumors. We present the case of a young female patient without a personal pathological history, who complained of intense, diffuse, intermittent, non-systematic abdominal pain and who underwent ultrasound examination, followed by contrast-enhanced ultrasound. With this technique, we evidenced a solid extrahepatic tumor, which was mobile at the patient's change of position and had the hemodynamic features of FNH. The article also tackles the problem of intra-abdominal pedunculated tumors.