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D P Naidich

Publications and source records attributed to D P Naidich.

At least 19 recordsLinked to original sources

Early Lung Cancer Action Project: overall design and findings from baseline screening.

BACKGROUND: The Early Lung Cancer Action Project (ELCAP) is designed to evaluate baseline and annual repeat screening by low-radiation-dose computed tomography (low-dose CT) in people at high risk of lung cancer. We report the baseline experience. METHODS: ELCAP has enrolled 1000 symptom-free volunteers, aged 60 years or older, with at least 10 pack-years of cigarette smoking and no previous cancer, who were medically fit to undergo thoracic surgery. After a structured interview and informed consent, chest radiographs and low-dose CT were done for each participant. The diagnostic investigation of screen-detected non-calcified pulmonary nodules was guided by ELCAP recommendations, which included short-term high-resolution CT follow-up for the smallest non-calcified nodules. FINDINGS: Non-calcified nodules were detected in 233 (23% [95% CI 21-26]) participants by low-dose CT at baseline, compared with 68 (7% [5-9]) by chest radiography. Malignant disease was detected in 27 (2.7% [1.8-3.8]) by CT and seven (0.7% [0.3-1.3]) by chest radiography, and stage I malignant disease in 23 (2.3% [1.5-3.3]) and four (0.4% [0.1-0.9]), respectively. Of the 27 CT-detected cancers, 26 were resectable. Biopsies were done on 28 of the 233 participants with non-calcified nodules; 27 had malignant non-calcified nodules and one had a benign nodule. Another three individuals underwent biopsy against the ELCAP recommendations; all had benign non-calcified nodules. No participant had thoracotomy for a benign nodule. INTERPRETATION: Low-dose CT can greatly improve the likelihood of detection of small non-calcified nodules, and thus of lung cancer at an earlier and potentially more curable stage. Although false-positive CT results are common, they can be managed with little use of invasive diagnostic procedures.

Aged

Multinodular disease: anatomic localization at thin-section CT--multireader evaluation of a simple algorithm.

PURPOSE: To evaluate the interobserver variability and accuracy of an algorithm for anatomic localization of small nodules evident on thin-section computed tomographic (CT) images of the lungs. MATERIALS AND METHODS: Four experienced chest radiologists independently evaluated thin-section CT images in 58 patients by using an algorithm and a standard score sheet. Nodules were placed into four possible anatomic locations or categories: perilymphatic, random, associated with small airways disease, or centrilobular. Algorithm accuracy was assessed by comparing the localization by the observers to that expected for each specific disease in the study group on the basis of reports in the literature. Interobserver variability was assessed by placing cases into one of three groups: (a) complete concordance, (b) triple concordance, and (c) discordant. RESULTS: All observers agreed in 79% (46 of 58) of the cases with regard to nodule localization; three of the four concurred in an additional 17% (10 of 58). The observers were correct in 218 (94%) of 232 localizations in the 58 cases. There were no apparent differences in the number of either discordant or incorrect localizations between the observers. The most noteworthy source of error and of disagreement between observers was the confusion of perilymphatic and small airways disease-associated nodules in a small number of cases. CONCLUSION: The proposed algorithm is reproducible and accurate in the majority of cases and facilitates nodule localization at thin-section CT.

Adult

Pulmonary nodule detection: low-dose versus conventional CT.

PURPOSE: To quantitate the effectiveness of low-dose computed tomography (CT) in the identification of pulmonary nodules while controlling for anatomic nodule characteristics and to establish what factors lead to reduced diagnostic sensitivity at low-dose CT. MATERIALS AND METHODS: Each of six participating radiologist independently rated 200 image panels by using a four-point confidence scale. Conventional images were obtained at 200 mAs; low-dose images were obtained at 20 mAs. To fully control their characteristics, nodules were simulated with a given diameter, shape, and section thickness while preserving the resolution, noise level, and reconstruction artifacts of the original images. Panels were matched so that nodules on low-dose and conventional images had equivalent sizes, locations, and relationships to blood vessels. RESULTS: Among 864 positive panels, 259 (60%) of 432 low-dose panels and 272 (63%) of 432 conventional panels were correctly interpreted (P = .259). Lowering the x-ray dose significantly reduced the detectability of peripheral nodules (P = .019) and nodules separated from blood vessels (P = .044). Surprisingly, 3-mm nodules were detected with approximately equal sensitivity (P = .181) at conventional and low-dose CT. The specificity of low-dose images was 88% (148 of 168 panels) versus 91% (153 of 168 panels) for conventional images (P = .372). CONCLUSION: Low-dose CT is acceptable for pulmonary nodule identification, making it suitable for primary screening. These results confirm the strong effect of size, location, and angiocentricity on the sensitivity of nodule detection with conventional CT.

Computer Simulation

Non-small cell lung carcinoma: usefulness of unenhanced helical CT of the adrenal glands in an unmonitored environment.

PURPOSE: To evaluate routine non-contrast material-enhanced helical computed tomography (CT) of the adrenal glands in patients with non-small cell lung carcinoma to facilitate characterization of adrenal masses detected in an unmonitored environment (i.e., the radiologist on duty did not look at the acquired images before the patient left the scanner). MATERIALS AND METHODS: One hundred consecutive patients with non-small cell lung carcinoma were referred for CT evaluation of the chest; chest and abdomen; or chest, abdomen, and brain. All underwent unenhanced CT of the adrenal glands before the requested CT examination. The morphologic features, size, and attenuation values of the adrenal masses were calculated. Attenuation values of adrenal masses from prior imaging, if available, were compared with those at follow-up imaging to classify these masses. Variable unit cost increase in obtaining these additional images was estimated. RESULTS: Fifteen adrenal masses were identified in 13 patients. In one patient, bilateral ill-defined adrenal masses were present. In 12 patients, 13 masses were sharply circumscribed: Seven were less than 10 HU and six were 20 HU or greater at unenhanced CT. Nine of these 12 patients received iodinated contrast material. Without the unenhanced CT, 10 adrenal masses in these nine patients would have been indeterminate for malignancy. In six of these nine patients, the adrenal mass was the only potential site of metastatic disease. The unenhanced CT data helped classify three of these masses as benign-10 HU or less- and three as indeterminate-greater than 10 HU. CONCLUSION: Unenhanced CT of the adrenal glands can prospectively characterize adrenal masses and obviate further examination in patients with lung carcinoma.

Adrenal Gland Neoplasms

Transbronchial needle aspiration (TBNA) in patients infected with HIV.

Transbronchial needle aspiration (TBNA) of intrathoracic lymph nodes has been shown to be useful in the diagnosis and staging of bronchogenic carcinoma. With the exception of sarcoidosis, the usefulness of TBNA has not been widely investigated in other clinical settings. We investigated the utility of TBNA with a 19-gauge histology needle in HIV-infected patients with mediastinal and hilar adenopathy at Bellevue Hospital Center. We performed 44 procedures in 41 patients. Adequate lymph node sampling was obtained in 35 of 44 (80%), and diagnostic material was obtained in 23 of 44 (52%) procedures. TBNA was the exclusive means of diagnosis in 13 of 41 (32%) patients. Of the 44 procedures, 23 (52%) were performed in patients with mycobacterial disease, with TBNA providing the diagnosis in 20 of 23 (87%). In these patients, positive TBNA specimens included smears of aspirated materials for acid-fast bacilli in 11, mycobacterial culture in 14, and histology in 15. In other diseases, TBNA diagnosed sarcoidosis with noncaseating granulomata in 2 of 4 patients and non-small cell lung cancer in 1 of 2 patients. TBNA was not helpful in other diseases including Pneumocystis carinii pneumonia, infection with Cryptococcus or Nocardia, bacterial pneumonia, viral pneumonia, and Kaposi's sarcoma. No pulmonary diagnosis was established in five patients. No complications of TBNA occurred. We conclude that TBNA through the flexible bronchoscope is safe and effective in the diagnosis of intrathoracic adenopathy in HIV-infected patients, and is particularly efficacious in the diagnosis of mycobacterial disease. Furthermore, TBNA may provide the only diagnostic specimen in almost one-third of HIV-infected patients, thereby sparing these patients more invasive procedures such as mediastinoscopy.

AIDS-Related Opportunistic Infections

Volumetric (helical/spiral) CT (VCT) of the airways.

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.

Humans

Pulmonary aspergilloma and AIDS. A comparison of HIV-infected and HIV-negative individuals.

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.

AIDS-Related Opportunistic Infections

AIDS-related airway disease.

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.

AIDS-Related Opportunistic Infections

Review: pneumothorax in patients with AIDS-related Pneumocystis carinii pneumonia.

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.

AIDS-Related Opportunistic Infections

Differentiation of the ILO boundary chest roentgenograph (0/1 to 1/0) in asbestosis by high-resolution computed tomography scan, alveolitis, and respiratory impairment.

High-resolution computed tomography (HRCT) scans have been advocated as providing greater sensitivity in detecting parenchymal opacities in asbestos-exposed individuals, especially in the presence of pleural fibrosis, and having excellent inter- and intraobserver reader interpretation. We compared the 1980 International Labor Organization (ILO) International Classification of the Radiographs of the Pneumoconioses for asbestosis with the high-resolution CT scan using a grid scoring system to better differentiate normal versus abnormal in the ILO boundary 0/1 to 1/0 chest roentgenograph. We studied 37 asbestos-exposed individuals using the ILO classification, HRCT grid scores, respiratory symptom questionnaires, pulmonary function tests, and bronchoalveolar lavage. We used Pearson correlation coefficients to evaluate the linear relationship between outcome variables and each roentgenographic method. The normal HRCT scan proved to be an excellent predictor of "normality," with pulmonary function values close to 100% for forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), total lung capacity (TLC), and carbon monoxide diffusing capacity (DLCO) and no increase in BAL inflammatory cells. Concordant HRCT/ILO abnormalities were associated with reduced FEV1/FVC ratio, reduced diffusing capacity, and alveolitis consistent with a definition of asbestosis. In our study, the ILO classification and HRCT grid scores were both excellent modalities for the assessment of asbestosis and its association with impaired physiology and alveolitis, with their combined use providing statistical associations with alveolitis and reduced diffusing capacity.

Asbestosis

Diffuse lung disease: assessment with helical CT--preliminary observations of the role of maximum and minimum intensity projection images.

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.

Adult

Bronchiectasis: CT/clinical correlations.

The association between bronchiectasis and human immunodeficiency virus infection, the resurgence of tuberculosis, especially in urban and immunocompromised patients, and the recognition of bronchiectasis as a manifestation of rejection in the transplant population are emerging clinical settings in which establishing the diagnosis of bronchiectasis is becoming increasingly important. High-resolution CT, by virtue of its well-established accuracy, is currently accepted as the optimal noninvasive means of diagnosing bronchiectasis. However, reliable diagnosis requires meticulous attention to technique and a thorough knowledge of potential pitfalls. These include, among others, respiratory and cardiac motion artifacts as well as effects of collimation and electronic windowing. It also is important to recognize diseases that may mimic the appearance of bronchiectasis as well as unusual manifestations of bronchiectasis that may obscure the diagnosis.

Acquired Immunodeficiency Syndrome

Airways and lung: correlation of CT with fiberoptic bronchoscopy.

Recent advances in computed tomography (CT) and fiberoptic bronchoscopy (FOB) have led to confusion concerning the optimal use of these modalities, especially with regard to each other. The present review summarizes the current understanding of the role of CT in relation to FOB. Emphasis is placed on optimization of CT technique and basic principles of interpretation of the images. In addition, an in-depth evaluation is presented of the advantages and limitations of CT and FOB in the analysis of both focal and diffuse diseases of the airways and lung parenchyma.

Bronchoscopy

Unusual lymphoproliferative disorders in nine adults with HIV or AIDS: CT and pathologic findings.

PURPOSE: To identify characteristic computed tomographic (CT) findings in unusual pulmonary lymphoproliferative disorders seen in adults with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: The authors retrospectively reviewed the CT scans and pathologic specimens from nine patients with pulmonary lymphoproliferative disorders. CT scans were evaluated for nodules, reticulation, areas of ground-glass attenuation, consolidation, and bronchial disease. Changes seen in pathologic specimens were classified as consistent with classic lymphocytic interstitial pneumonitis (LIP), mucosa-associated lymphoid tissue lymphoma (MALTOMA), or atypical lymphoproliferative disorder (ALD). Immunopathologic results were reviewed when available. RESULTS: Eight patients had AIDS. Five patients had classic LIP. One patient had MALTOMA, and three patients had ALD. Altogether, 2-4-mm-diameter nodules were the predominant CT finding in eight patients; these were peribronchovascular in four patients. The presence of interstitial nodules correlated with the pathologic finding of nodular disease in seven patients. CONCLUSION: Familiarity with these AIDS-related disorders and their CT appearance should assist in the differential diagnosis.

Acquired Immunodeficiency Syndrome