Faculty Bibliography

The role of computed tomography (CT) in the diagnosis of mediastinal tuberculous lymphadenitis was evaluated retrospectively in 25 human immunodeficiency virus (HIV)-infected patients (19 had AIDS). In all cases, the diagnosis of tuberculosis was established by mycobacterial culture and/or histologic evaluation. The most characteristic CT finding was the presence of low-density mediastinal and hilar lymph nodes in 16 of 19 (84 percent) patients with AIDS and four of six (67 percent) HIV-seropositive patients without AIDS. Marked enhancement of the periphery of nodes was identified in five cases, all in patients with documented AIDS. In most cases, lymphadenopathy proved to be massive, presenting as extensive, heterogenous soft-tissue lesions, presumably the result of coalescence of groups of matted nodes. We conclude that low-density mediastinal and/or hilar lymph nodes on CT, while not pathognomonic, is sufficiently characteristic for tuberculosis to warrant empiric antituberculosis therapy pending results of cultures

Thoracic disease in the HIV negative immunocompromised host is most frequently caused by infection. Patterns of involvement produced on the chest radiograph include (1) lobar or segmental consolidation, (2) nodules with rapid growth and/or cavitation, and (3) diffuse lung disease. The lung also may be directly involved by lymphoma, metastases, drug reactions, radiation pneumonitis, or nonspecific interstitial pneumonitis. The lung is a frequent target organ for opportunistic infections in AIDS patients, particularly of Pneumocystis carinii pneumonia and tuberculosis. Computed tomography may be particularly helpful in these patients in the detection of early disease and in the characterization of patterns and extent of involvement as well as complications.

The authors describe the radiographic appearance of the left atrial catheter, a widely used postsurgical intracardiac device. Recognition of the characteristic appearance of this catheter should be of value in detection of potential complications, including line fracture with resultant retention and/or embolization, infection, prosthetic valve dysfunction, and even cardiac tamponade

High-resolution CT (HRCT) and chest radiographs were compared in nine patients with miliary lung disease. In all cases, miliary disease was documented to be infectious in etiology; six of these patients proved to be human immunodeficiency virus (HIV) positive. A mixture of both sharply and poorly defined 1-3 mm nodules was seen in all cases, many of the latter having an appearance indistinguishable from airspace nodules. Other features attributable to the presence of nodules included nodular interlobular septae, nodular irregularity of vessels, subpleural dots, and studded fissures. Diffuse intra- and interlobular septal thickening also proved common, seen in all but one case (91%). Based on limited HRCT-pathologic correlation, CT findings appear primarily to be due to granulomatous foci developing in a seemingly random distribution involving both pulmonary airspaces as well as the interstitium. It is concluded that in the appropriate clinical setting this constellation of findings is characteristic of miliary disease; the role of HRCT especially in the early diagnosis of miliary disease in HIV positive patients remains to be determined prospectively

This report describes the diagnostic workup of a case of a pseudoaneurysm of the heart resulting from Staphylococcal pericarditis and/or abscesses of the myocardium. The pericardial effusion and myocardial abscesses were detected on 2D echocardiography and computed tomography. The resulting pseudoaneurysm could be demonstrated on magnetic resonance imaging and color Doppler ultrasound, and confirmed by left ventriculography. Color-encoded Doppler ultrasound alone would have provided the definitive diagnosis of the aneurysm.

The progression of lung disease in patients with cystic fibrosis (CF) was evaluated with chest radiography. The severity and extent of the various radiographic changes were scored with the Chrispin or the Birmingham method, which involves the use of imprecise and subjective terms, such as line shadows, large pulmonary shadows, and nodular cystic lesions. Although computed tomography (CT) has been shown to be helpful in the evaluation of lung disease in CF, no scoring system or other objective criteria have been developed for the evaluation of the wide range of pulmonary changes in these patients. A CT scoring system was devised that incorporates all of the changes seen in the lungs of patients with CF. Such a scoring system may facilitate objective evaluation of existing and newly developed therapeutic regimens and may be a valuable tool in the preoperative evaluation of patients being considered for lobectomy or bullectomy and in the selection of patients for lung transplantation.

To date, few reports have attempted to correlate plain radiographic findings with computed tomography (CT) in assessing pulmonary disease in patients who have acquired immunodeficiency syndrome (AIDS). This report focuses on the most common pulmonary manifestations, with particular emphasis placed on those entities for which there is a potential role for CT. This includes identification of occult disease, especially the early diagnosis of Pneumocystis carinii pneumonia, as well as identification of unsuspected lung abscesses and cavities; characterization of diffuse parenchymal disease in patients who have abnormal radiographs; identification and characterization of mediastinal lymphadenopathy, especially in differentiating between neoplastic and non-neoplastic causes; and finally, use of CT to perform CT-guided transthoracic needle biopsies