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Biomedical subjects

P Batra

Publications and source records attributed to P Batra.

At least 37 records · Page 2Linked to original sources
PubMed1994

Intrathoracic calcifications: radiographic features and differential diagnoses.

Intrathoracic calcifications occur in a wide variety of disorders. Although they are usually harmless sequelae of remote processes, calcifications provide important information for establishing the diagnosis or for evaluating the progression of known disease. They may arise in the pulmonary parenchyma, mediastinum, hilar and mediastinal lymph nodes, pleura, chest wall, or any combination of these structures. The cause of the calcification may be determined by means of the location and pattern of the calcifications within the lung parenchyma and knowledge of the associated clinical features. Calcifications in the thorax are frequently manifestations of previous infectious processes. Less often, they may be due to neoplasms, metabolic disorders, occupational exposure, or previous medical therapy. Large intrathoracid calcifications are usually identified on conventional chest radiographs; detection of smaller calcifications may require use of other imaging modalities, such as dual-energy digital radiography, fluoroscopy, radionuclide scanning, computed tomography (CT), and high-resolution CT.

Calcinosis↗
PubMed1993

The effect of irreversible image compression on diagnostic accuracy in thoracic imaging.

RATIONALE AND OBJECTIVES: Digital image compression reduces the storage requirements and network traffic on picture archiving and communications systems. Full-frame bit-allocation (FFBA) is an irreversible image-compression method based on the discrete cosine transform that provides for high compression ratios with a high degree of image fidelity. METHODS: One hundred twenty-two posteroanterior chest radiographs were obtained on patients in an ambulatory patient setting, including 30 cases of interstitial lung disease, 45 images containing combinations of lung nodules (N = 37) or mediastinal masses (N = 39), and 47 normal images containing none of the pathology for which we were testing. The images were digitized (nominal 2 K x 2 K x 12-bit resolution), printed on a 35 x 35-cm hard copy format, and compressed at an approximate compression ratio of 20:1. Observer performance tests were conducted with five radiologists using receiver operating characteristics analysis on digitized uncompressed and compressed hard copy images. RESULTS: There were no significant differences between the two display conditions for the detectability of any of the thoracic abnormalities. CONCLUSIONS: Our preliminary results suggest that irreversible image compression at ratios of 20:1 may be acceptable for use in digital thoracic imaging.

Algorithms↗
PubMed1992

Pulmonary coccidioidomycosis.

Coccidioidomycosis is a fungal disease endemic in the southwestern desert area of the United States. The infection is acquired by inhalation of arthrospores, and 60% of the infections are asymptomatic. Chest radiographic abnormalities are common and may even be seen in asymptomatic cases. In patients with acute infection, segmental or lobar consolidation and nodular or patchy pulmonary opacities are frequent. Hilar and mediastinal adenopathy may be present in 20% of cases, usually with parenchymal findings. A small pleural effusion may occur in 20% of cases. Approximately 5% of patients with primary disease are left with chronic, residual lesions of the lung. These consist of nodules, cavities, pneumonia, adenopathy, pleural effusion, fibrosis, bronchiectasis, and calcification. Rarely, in about 0.5% of cases, the infection may disseminate to any organ. The chest radiograph demonstrates a miliary or reticulonodular pattern and mediastinal adenopathy. Overall the disease is benign in nature; but patients with severe, progressive pulmonary or disseminated disease often require medical and occasionally surgical management.

Coccidioidomycosis↗
PubMed1992

Imaging techniques in the evaluation of pulmonary parenchymal neoplasms.

Conventional PA and lateral chest radiographs continue to be the initial examination of choice to evaluate patients who are suspected of having a pulmonary parenchymal neoplasm. A lung lesion can be characterized as probably benign or malignant based on its radiographic appearance (size, shape, margins, presence of calcification, cavitation or air bronchograms, growth rate). A spiculated or lobulated lesion greater than 3 cm in size that is noncalcified is highly suspicious for malignancy. A lung lesion less than 3 cm in size with smooth borders that appears noncalcified on conventional radiographs should be examined by CT, including densitometry to detect calcification or fat, which indicates benignity. In patients with known lung cancer, CT can help to stage the tumor by indicating hilar or mediastinal involvement, or distant metastases. Currently, MR imaging has a limited role, but can be used as a "problem solving" modality for selected cases in evaluating pulmonary parenchymal neoplasms.

Diagnosis, Differential↗
PubMed1991

Effect of aflatoxin B1 on the efficacy of turkey herpesvirus vaccine against Marek's disease.

The effect of feeding aflatoxin B1 (AFB1) (0.5 ppm) was studied in young chicks. The frequency and the severity of gross and microscopic lesions of Marek's disease were significantly higher in those birds which had been vaccinated with turkey herpesvirus (HVI) and birds challenged with Marek's disease virus which had been given AFB1 in the feed than in those given normal feed. The protective efficacy of HVT vaccine, as judged on the basis of gross and histopathological lesions, was 86.1 and 77.3 per cent in normally fed birds in comparison to 37.6 and 8 per cent in AFB1 fed birds.

Aflatoxin B1↗
PubMed1991

Mediastinal masses: magnetic resonance imaging in comparison with computed tomography.

Seventy-eight patients with mediastinal abnormalities were imaged with magnetic resonance imaging (MRI) to evaluate mediastinal masses and associated lung, pleural, or chest wall disease. Magnetic resonance images were compared with computed tomography (CT) scans, which were available in 45 patients. While MRI and CT were equally effective in demonstrating mediastinal lesions, CT was superior for displaying calcification within a mass in eight patients and for demonstrating associated lung abnormality in four patients. Computed tomography should remain the imaging procedure of choice after chest radiography to evaluate mediastinal masses, although MRI may be indicated in selected patients.

Adolescent↗
PubMed1991

Pulmonary dysfunction in advanced liver disease: frequent occurrence of an abnormal diffusing capacity.

PURPOSE: Abnormalities in pulmonary function have been reported in association with chronic liver disease of varied etiology. The aim of this study was to better define the frequency and nature of these abnormalities in patients who were being evaluated for liver transplantation. PATIENTS AND METHODS: We performed a battery of pulmonary function tests and chest radiographs in 116 consecutive patients (50 men, 66 women; aged 19 to 70 years, mean 44.6 years) with severe advanced liver disease who were hospitalized specifically for evaluation for possible orthotopic liver transplantation and were able to perform technically satisfactory tests. In 17 patients, quantitative whole-body technetium-99m macroaggregated albumin perfusion scanning was also performed for assessment of possible right-to-left shunting through intrapulmonary vascular dilatations. RESULTS: The most commonly affected test of lung function was the single-breath diffusing capacity for carbon monoxide (DLCO), which was abnormal in 48%, 45%, and 71% of patients who never smoked, former smokers, and current smokers, respectively. Ventilatory restriction was noted in 25% of all patients, airflow obstruction (reduced ratio of forced expiratory volume in 1 second to forced vital expiratory volume in 1 second to forced vital capacity) in only 3%, and a widened alveolar-arterial oxygen gradient in 45%. Diffusion impairment was accompanied by a restrictive defect in only 35% of the patients and by an abnormally widened alveolar-arterial oxygen gradient in 60%. When diffusion impairment was accompanied by an oxygenation defect, it was also associated with a significantly increased right-to-left shunt fraction (mean 24.9%) assessed from quantitative whole-body perfusion imaging. On the other hand, isolated diffusion impairment unaccompanied by significant hypoxemia (noted in approximately a third of the patients with a reduced DLCO) was not associated with evidence of significant intrapulmonary shunting (mean right-to-left shunt fraction 6.7%). CONCLUSIONS: Most patients with advanced liver disease have one or more types of abnormality in lung function, a reduced DLCO being the single most common functional defect. Mechanisms accounting for the abnormality in gas transfer may include intrapulmonary vascular dilatations, diffuse interstitial lung disease, pulmonary vaso-occlusive disease, and/or ventilation-perfusion imbalance.

Adult↗
PubMed1991

Magnetic resonance imaging of chest wall lesions.

Magnetic resonance imaging (MRI) demonstrates surface anatomy, nerves, and soft tissue pathology. Selective placement of the cursor lines in MRI displays specific anatomy. The MR images can then be used as adjunct in teaching surface anatomy to medical students and to other health professionals. Because the normal surface anatomy could be imaged at UCLA's radiology department, it was decided to image soft tissue abnormalities with MR to assist in patient care. Patients imaged were scheduled for special procedures of the chest or staging lymphangiograms. Patients were placed into categories depending on known diagnosis or interesting clinical presentation. The diagnostic categories included Hodgkin's disease, melanoma, carcinomas (eg, lung or breast), lymphedema, sarcomas, dermatological disorders, and neurological disorders. All images were orchestrated by the radiologist. This article discusses both the teaching and clinical impact on patient care.

Adult↗
PubMed1991

AIDS: immunologic abnormalities following human immunodeficiency virus infection.

Following human immunodeficiency virus (HIV) infection, there is an ordered progression of immunologic abnormalities that results from the selective infection of the T4 helper/inducer subset of T lymphocytes. The loss of helper T-cell function disrupts both the cellular and humoral aspects of the immune response. The T lymphocytes decrease in both number and function. The peripheral blood B lymphocytes demonstrate marked polyclonal activation and are unable to mount a serologic response to new antigens. The infected monocytes and macrophages serve as reservoirs for HIV and act as vehicles that transport the virus to target organs. Decreased activity of natural killer cells may promote progression of acquired immunodeficiency syndrome (AIDS). Factors that suppress the reaction of T and B lymphocytes to stimuli have been identified in the sera of AIDS patients. In conclusion, HIV infection causes progressive dysfunction and destruction of the entire immune system, resulting in severe opportunistic infections, neoplasms, and shortened survival of AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Anatomy of the thorax and shoulder girdle displayed by magnetic resonance imaging.

In 1971, radiographic anatomy of the human body was added to the gross anatomy course at UCLA. Radiographic contrast studies and plain anatomical displays were formulated into teaching packages for all organ systems. Residents presented each package to first-year medical students in the dissection laboratory to augment the teaching of anatomy. In November 1984, magnetic resonance imaging was instituted in the radiology department. Imaging the chest produced coronal and axial planes which displayed the muscles and soft tissues of the thorax. In 1986, the authors presented their study of MR anatomy of the chest and shoulder girdle to the American Association of Anatomists. The purpose of this presentation is to demonstrate the anatomy of the thorax and shoulder girdle as displayed by magnetic resonance, correlated with regional anatomy, with emphasis on soft tissue structures.

Humans↗
PubMed1990

Current use of imaging in the evaluation of primary mediastinal masses.

A wide variety of lesions occur in the mediastinum in patients of every age. Twenty five to 50 percent of these primary mediastinal masses may be malignant, making early diagnosis and therapy crucial. Since most arise from normal structures in the region, localization of lesions to compartments of the mediastinum may assist in diagnosis. This article reviews imaging techniques for lesions originating in the mediastinum.

Arteriovenous Malformations↗
PubMed1990

Ventilatory and diffusion abnormalities in potential heart transplant recipients.

Few data are available concerning pulmonary function in patients with severe chronic congestive heart failure. Of 315 patients evaluated for potential cardiac transplantation at UCLA, 132 underwent pulmonary function tests. The latter patients had severe heart failure with a mean left ventricular ejection fraction of 19 percent and mean cardiac index of 2.1 L/min/m2. Diffusion impairment either alone or combined with restrictive and/or obstructive ventilatory defects occurred in 67 percent of the patients evaluated. Diffusion impairment occurred as the sole abnormality in 31 percent of the patients and in combination with a restrictive ventilatory defect in 21 percent. A reduction in diffusing capacity has not been previously described as a frequent finding in patients with chronic congestive heart failure. In contrast to other studies involving patients with acute heart failure, obstructive ventilatory defects were uncommon. None of the lung function abnormalities was associated with smoking status, prior drug use, chest roentgenographic changes, hemodynamic findings, or clinical features, including duration of congestive heart failure. The mechanism for the diffusion impairment is unclear but could be due to chronic passive congestion with pulmonary fibrosis and/or recurrent pulmonary emboli. Recognition of diffusion impairment as a common finding in patients with severe chronic congestive heart failure who are candidates for heart transplantation is important for proper interpretation of possible post-transplant changes in diffusing capacity due to other causes.

Adult↗
PubMed1990

Enhancing magnetic resonance images using water bags.

Fascial planes between tissues are separated by connective tissue, fat, and blood vessels. Magnetic resonance imaging displays surface anatomy and soft tissues. Our team has been successful in demonstrating brachial plexus nerves as a model of magnetic resonance anatomy. Radiologists have devised methods to increase the resolution of images by suppressing noise and increasing the sharpness of the image. We added water bags to a 0.3 tesla permanent magnet suppressing the noise and increasing the signal to image our patients. The images proved to be sharper.

Humans↗
PubMed1989

Mediastinal germ cell tumor in a young woman.

Primary mediastinal germ cell malignancies are uncommon neoplasms, usually presenting in young men. We review a case of a primary mediastinal seminoma occurring in a 23-year-old woman. The differential diagnosis, work-up and therapy for these lesions is discussed with emphasis on the role of magnetic resonance imaging in the evaluation of anterior mediastinal masses.

Adult↗
PubMed1989

Bronchoalveolar lavage cell and lymphocyte phenotype profiles in healthy asbestos-exposed shipyard workers.

The cellular and lymphocyte phenotypic composition of bronchoalveolar lavage (BAL) fluid and peripheral blood (PB) from 15 healthy, nonsmoking, asbestos-exposed shipyard workers (AEW) and 10 nonsmoking, age-matched unexposed workers (UEW) were compared. None of the AEW had clinical, radiographic, or physiologic evidence of asbestosis, but six had radiographic evidence of pleural plaques and/or thickening. The mean duration of asbestos exposure was 16.3 +/- 2.3 yr, and the mean period since exposure was 10.8 +/- 0.5 yr. All but three of the AEW and none of the UEW had asbestos bodies detected in the first 20 ml of BAL fluid recovered (0.1 to 35 asbestos bodies/ml). The AEW had a significantly higher mean percentage (19.1 +/- 2.8% versus 9.7 +/- 1.6%) and concentration (31.6 +/- 5.2 x 10(3) cells/ml versus 14.7 +/- 2.5 x 10(3) cells/ml) of BAL lymphocytes compared with that in the UEW, with an increased mean concentration of each phenotype measured. In PB, the mean lymphocyte concentration was also higher in the AEW than in the UEW (2.0 +/- 0.3 x 10(3) cells/ml versus 1.5 +/- 0.3 x 10(3) cells/ml), but the difference was not statistically significant, and there was no increase of any phenotype measured. BAL lymphocytosis did not correlate with exposure history or BAL asbestos body count, but was greater in AEW with pleural abnormality (30.1 +/- 2.9% versus 11.8 +/- 1.6%). BAL concentrations of CD-20, CD-3, and CD-4, but not of CD-8 cells were significantly increased compared with those in the AEW without pleural abnormality. Further longitudinal studies are needed to determine the prognostic significance of these findings.

Adult↗
PubMed1989

Nerves on magnetic resonance imaging.

Nerves are often visualized on magnetic resonance imaging (MRI) studies of the soft tissues on the chest and shoulder girdle. To learn the reasons for the contrast between the nerves and adjacent tissues, the authors obtained a fresh specimen containing part of the brachial plexus nerves from the left axilla and compared MRI with x-ray projections and photomicrographs of histologic sections. The results suggest that the high signals from the nerves stand out in contrast to the low signals from their rich vascular supply.

Connective Tissue↗