UCLA Radiological Sciences Proceedings

Alagille Syndrome is a multisystem genetic disorder characterized by paucity of intrahepatic bile ducts, which can lead to early cirrhosis and an increase in the risk of developing focal liver lesions, including hepatocellular carcinoma. Therefore, patients with Alagille syndrome are often followed with routine imaging surveillance. However, it can be challenging to distinguish incidentally found benign liver tumors from their malignant counterparts in this subset of patients. Here we present the case of a giant regenerative hepatic nodule in a 17-year-old woman with Alagille syndrome. The case is presented with associated imaging studies that favored a diagnosis of benign hyperplasia, confirmed by the results of histologic examination.

One of the three components of the dorsal extensor hood, the sagittal band is a sheet of connective tissue that provides lateral stability to the extensor digitorum tendon at the metacarpophalangeal joint. Rupture of one of the two portions of the sagittal band can lead to contralateral subluxation or dislocation of the extensor tendon. Closed sagittal band injury is commonly associated with high-energy impact or inflammatory conditions, such as rheumatoid arthritis. In cases of high-energy impact, a closed sagittal band injury may co-occur with a “boxer’s knuckle,” the metacarpophalangeal joint and the extensor mechanism injury that has been historically reported in boxers after blunt impact to the joint in forceful flexion. In this case report, we present a 64-year-old woman with no known history of rheumatoid arthritis and with a closed sagittal band injury received while using the fists to support changing her body position in bed. Ultrasonography and MRI are useful in the evaluation of a sagittal band injury. The use of dynamic ultrasound imaging can help visualize the extensor tendon subluxation with metacarpophalangeal joint flexion and confirm the diagnosis of sagittal band injury.