Juxtadiaphragmatic masses occur frequently as cardiophrenic-angle densities seen on chest radiographs, and they are usually benigh. Pericardial cysts, eventration of a hemidiaphragm, and foramen of Morgagni hernias are the most common of these lesions, although tumors of the mediastinum (including primary and metastatic malignancies, lymphoma, and other benign tumors) also occur in this area. Noninvasive examinations such as chest fluoroscopy, barium studies of the gastrointestinal tract, and radionuclide liver-spleen scans (1,2) have been used to evaluate these masses. However, these examinations are often inconclusive and do not permit differentiation between supradiaphragmatic and infradiaphragmatic lesions. Diagnostic pneumoperitoneum has occasionally been employed (31, but this is invasive and uncomfortable for the patient. B-mode sonography was recently reported to be of value in the evaluation of two such masses ( 4 ) . We wish to report two additional cases in which B-mode gray-scale sonography using the liver as a sonic window was definitive in evaluating right-cardiophrenic-angle masses. Insofar as we know, this is the first reported diagnosis of a pericardial cyst using the transhepatic approach.
CASE REPORTS
Case 1 J.P., a 3-year-old white boy with Down's syndrome, was referred to St. Louis Children's Hospi-From the