Faculty Bibliography

The increasing use of high-resolution CT (HRCT) should lead to a reconsideration of the traditional manner in which patients with diffuse interstitial lung disease are evaluated. HRCT is no longer used only in the assessment of rare diseases or exclusively in academic medical centers. There are many clinically important uses of HRCT in patients with pulmonary symptoms; in some cases, the imaging findings are diagnostic and obviate tissue diagnosis. The frequency with which this occurs depends on the type and stage of disease present and on the skill and confidence of the individual interpreting the images Accurate HRCT interpretation also requires correlation with clinical information. The diagnostic evaluation of patients with known or suspected lung disease should involve pulmonologists, thoracic radiologists, and thoracic surgeons

OBJECTIVE AND METHODS: While pulmonary aspergilloma has been well described in immunocompetent hosts, to date and to our knowledge, there has not been a description of pulmonary aspergilloma in the HIV-infected individual. A retrospective review of cases seen by the Bellevue Hospital Chest Service from January 1992 through June 1995 identified 25 patients with aspergilloma. To investigate the impact of HIV status on pulmonary aspergilloma, we compared clinical presentation, progression of disease, treatment, and outcome in the HIV-infected patient vs the HIV-negative patient with aspergilloma. RESULTS: Of the 25 patients identified, 10 were HIV-infected and 15 were HIV-negative. Predisposing diseases included tuberculosis (18/25, 72%), sarcoidosis (4/25, 16%), and Pneumocystis carinii pneumonia (3/25, 12%). All 25 patients had evidence of aspergilloma on chest CT. In addition, 17 of 25 patients had evidence of Aspergillus species in fungal culture, pathologic specimens, or immunoprecipitins. Hemoptysis was present in 15 of 25 (60%) (11/15 [73%] of the HIV-negative group vs 4/10 [40%] of the HIV-infected group). Severe hemoptysis (> 150 mL/d) occurred in 5 of 15 (33%) of the HIV-negative group vs 1 of 10 (10%) of the HIV-infected group. Disease progression occurred more frequently among the HIV-infected group (4/8, 50% vs 1/13, 8% in HIV-negative individuals). All patients with disease progression had lymphocyte subset CD4+ < 100 cells per microliter. Four of eight (50%) of the HIV-infected group vs 1 of 13 (8%) of the HIV-negative group died. SUMMARY AND CONCLUSIONS: We conclude the following: (1) although tuberculosis and sarcoidosis are the most prevalent predisposing diseases, P carinii pneumonia in the HIV-infected individual is a risk factor for pulmonary aspergilloma; (2) HIV-infected individuals with CD4+ < 100 cells per microliter are more likely to have disease progression despite treatment; and (3) HIV-negative patients are more likely to have hemoptysis requiring intervention

To our knowledge, the importance of airway disease in HIV-positive patients has been infrequently noted. This deficit likely reflects a combination of factors including lack of familiarity with recent changes in clinical and epidemiologic patterns of pulmonary manifestations of HIV infection and documented limitations of chest radiography for identifying and differentiating airway disease from other causes of pulmonary disease in HIV-positive patients. Familiarity with the imaging findings for these various entities should facilitate prompt diagnosis and treatment. The accuracy of CT in detecting airway disease [55-59] is well established and should be of value in excluding more common diseases that may be initially confused with airway abnormalities [60, 61]. Small airways disease, in particular, which may be occult or mimic an interstitial infiltrate on chest radiography, can be recognized with CT as likely representing infectious bronchitis or bronchiolitis. Patients with findings suggesting bacterial infections may benefit from empiric antibiotic therapy. CT also may be valuable for differentiating between various noninfectious pulmonary diseases, allowing a presumptive diagnosis of parenchymal Kaposi's sarcoma in the appropriate clinical context. In distinction, by detecting localized endobronchial or parenchymal abnormalities in patients with mycobacterial or fungal infections or lymphoma, CT may be valuable for deciding between various invasive methods of obtaining either histologic or bacteriologic diagnoses

Volumetric computed tomography (VCT) represents an important improvement over conventional CT for assessing most airway abnormalities. Elimination of misregistration due to variations in respiration coupled with decreased motion artifact and the ability to obtain routine overlapping sections allow a more confident estimation of the presence and extent of disease. Recently, attention has focused on newer reconstruction techniques including: multiplanar reconstructions (MPRs), including curved multiplanar reformations; multiplanar volume reconstructions (MPVRs) using ray projection techniques, such as maximum and minimum projection imaging; external rendering, or 3D-shaded surface displays; and, most recently, internal rendering or so-called 'virtual bronchoscopy'. Given the often redundant nature of many of these methodologies determining indications for their use remains to be established, especially by comparison to axial imaging. The purpose of this article is to review these various reconstruction techniques and, based on current knowledge, place them in an appropriate clinical context

A retrospective review was performed to describe the clinical characteristics, course, and outcome of pneumothorax for all patients admitted to Bellevue Hospital, New York, with AIDS who had Pneumocystis carinii pneumonia (PCP) diagnosed between January 1985, through July 1991. Of 1360 patients with AIDS and PCP, 67 patients (4.9%) were identified with pneumothorax; a group of 50 is the subject of this review. Of these 50 patients, 22 patients (44%) developed spontaneous pneumothorax, 15 patients (30%) developed pneumothorax during mechanical ventilation, and 13 patients (26%) had pneumothorax after an invasive procedure. Of the 22 patients with spontaneous pneumothorax, 8 had cystic parenchymal abnormalities on the chest radiograph and 6 had a history of PCP. The majority of patients were treated with tube thoracostomy and/or surgical intervention. All 15 patients who developed pneumothorax during mechanical ventilation died. Results of pathologic studies revealed varying degrees of interstitial inflammation and fibrosis interspersed with areas of hemorrhage and necrosis, and presence of P carinii cysts. Autopsy specimens obtained in two cases demonstrated multiple parenchymal cavities and evidence of an alveolar eosinophilic exudate with P carinii organisms. Spontaneous pneumothorax in patients with AIDS usually occurs in association with PCP and is associated with significant morbidity. Patients at risk include those with cystic lesions on chest radiograph and those patients with a history of PCP. Patients with AIDS and PCP who develop pneumothorax during mechanical ventilation have a poor outcome

PURPOSE: To evaluate assessment of diffuse lung disease with helical computed tomography (CT) and maximum intensity projection (MIP) and minimum intensity projection images. MATERIALS AND METHODS: Six patients with suspected lung disease (the control group) and 20 patients with documented disease underwent axial helical CT through the upper and lower lung fields. Findings on the MIP and minimum intensity projection images of each helical data set were compared with findings on the thin-section scan obtained at the midplane of the series. RESULTS: Owing to markedly improved visualization of peripheral pulmonary vessels (n = 26) and improved spatial orientation, MIP images were superior to helical scans to help identify pulmonary nodules and characterize them as peribronchovascular (n = 2) or centrilobular (n = 7). Minimum intensity projection images were more accurate than thin-section scans to help identify lumina of central airways (n = 23) and define abnormal low (n = 15) and high (ground-glass) (n = 8) lung attenuation. Conventional thin-section scans depicted fine linear structures more clearly than either MIP or minimum intensity projection images, including the walls of peripheral, dilated airways (n = 3) and interlobular septa (n = 3). MIP and minimum intensity projection images added additional diagnostic findings to those on thin-section scans in 13 (65%) of 20 cases. CONCLUSION: MIP and minimum intensity projection images of helical data sets may help diagnosis of a wide spectrum of diffuse lung diseases