A rare case of accessory liver lobe torsion in a pediatric patient who showed recurrent epigastralgia and who was treated by elective laparoscopic resection

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.

Torsion of an Accessory Liver Lobe in a Newborn

Accessory liver lobes are rare. We present the rare case of torsion of an accessory liver lobe in a neonate. A 13-day-old newborn presented with failure to thrive and hematemesis without fever. The initial workup with sonography, magnetic resonance imaging, and upper gastrointestinal study was suspicious of a duplication cyst, most likely in the posterior wall of the stomach. Laboratory and radiological findings were not suggesting a choledochal cyst. We performed a laparotomy with resection of the 3.2 × 2.1 × 1.1 cm mass. Intraoperatively, the cystic formation extended from of the liver bed up to the lesser curvature of the stomach. The mass was attached to the left liver lobe with fibrous bands. Histopathology revealed necrotic liver parenchyma with patent viable biliary ducts, indicative of an accessory liver lobe that underwent torsion in the perinatal period. The postoperative course and follow-up (6 months so far) were uneventful. To our knowledge, this is the youngest described patient in the literature with an accessory liver lobe torsion and the second case report concerning this entity in a neonate. It presents an extremely rare differential diagnosis in symptomatic neonates with a cystic mass in the upper abdomen.

Case report: A case of giant accessory hepatic lobe torsion combined with left hepatic vein branch thrombosis in a child

The accessory hepatic lobe (AHL) is a rare congenital malformation of the hepatic tissue, among which the giant AHL is the rarest in children. Patients without complications are usually asymptomatic, and most auxiliary examinations cannot provide a definitive preoperative diagnosis. Surgical procedure is the only recommended management for patients who suffered from the complications of AHL. We report the case of a rare pediatric giant AHL torsion combined with left hepatic vein branch thrombosis which was successfully treated by laparoscopic lobectomy followed by excision of AHL.