Radiographic appearances of the St. Jude Medical Valve.

The St. Jude Medical Valve (SJMV), one of the more popular prosthetic cardiac valves in use today, has been described as poorly visualized on plain radiographs, being visible only at fluoroscopy. The chest radiographs of 76 patients (85 valves) in whom the SJMV had been implanted were reviewed in order to assess the visibility and appearances of the SJMV. We found that the SJMV was visible postoperatively in 70 of the 76 patients (92%) on either frontal or lateral chest radiographs or both. Knowing the various normal appearances of the SJMV described here and the anatomic locations of the heart valves, radiologists should be able to visualize and identify this prosthetic valve on chest radiographs in the majority of patients.

Hepatic parenchymal gas after blunt trauma.

Hepatic parenchymal gas was demonstrated by computed tomography in a boy who had sustained severe blunt trauma to the abdomen 12 hours earlier. There was no clinical evidence of infection. Although previous reports have suggested that hepatic parenchymal gas indicates the presence of infection, such gas may also be a manifestation of severe blunt trauma without infection.