Atypical pleural tuberculosis presenting as an isolated pleural tuberculoma

Pleural tuberculosis is the most common extrapulmonary manifestation of tuberculosis, and is generally characterized by an effusion. The effusion is usually unilateral and residual pleural thickening or calcification is also observed in some cases. Manifestations of multiple pleural tuberculomas without associated effusion and history of tuberculosis or antituberculous therapy are rare and an isolated pleural tuberculoma is exceedingly rare. Herein, we report the first documented case of an isolated pleural tuberculoma, diagnosed by chest CT and pathological findings. Although rare, an isolated pleural tuberculoma should be added to the differential diagnosis of focal nodular pleural tumors, particularly in areas of high tuberculosis prevalence.     

Malignant pleural disease

The vast majority of pleural neoplasms invade the pleura secondarily and can be seen in patients with bronchogenic carcinoma, breast cancer, lymphoma, and ovarian or gastric carcinoma. Primary pleural neoplasms are less common, although they have developed notoriety since the up-surge of malignant mesothelioma and the knowledge of its connection to asbestos exposure. Other malignant primary tumors include localized fibrous tumor and pleural liposarcoma. In most patients with diffuse malignant pleural disease the chest radiograph shows pleural effusion with or without pleural thickening. Computed tomography (CT) usually provides precise localization and extent of the disease and may be of value in assessing chest wall and mediastinal involvement. In specific situations, magnetic resonance (MR) may be useful as a problem-solving tool when CT findings of chest wall or diaphragmatic invasion are equivocal or in patients with contraindication to intravenous administration of ionic contrast material.     

Flopping pleural cyst

We describe a patient with a large cyst of pleural origin a flopping movement within the pleural space with chaniging bodyposture. CT was of considerable value in determining the free movement of this lesion as well as suggesting its particular location and nature. Correspondence to: R.N. Sener     

Benign pleural diseases

The pleural space is a potential space under normal physiologic circumstances. It envelops the lung, the mediastinum, the diaphragm and the chest wall. A thin film of pleural fluid provides lubrication for the two pleural layers; only 2-10 ml of pleural fluid is present in healthy people. For the purposes of this review, pleural abnormalities will be divided into pleural effusion, pneumothorax, and pleural calcification.     

Asbestos-related benign pleural disease

Benign pleural disease is the commonest manifestation of asbestos exposure encountered by radiologists. Benign pleural thickening can appear as circumscribed parietal pleural plaques or as more diffuse thickening of the visceral pleura. Benign-asbestos induced pleural effusions are a significant and under-recognized manifestation of asbestos exposure with important sequelae, such as diffuse pleural thickening which may be associated with functional impairment and for which compensation may be sought. This review concentrates on the strengths and weaknesses of chest radiography and computed tomography for the detection and characterization of benign asbestos-related pleural disease and the relevance of imaging abnormalities to compensation and functional impairment.Peacock, C. (2000). Clinical Radiology55, 422-432.     

Radiation-induced malignant pleural mesothelioma

Malignant pleural mesothelioma is a rare and usually fatal disease. Its association with asbestosis is well recognized. The authors report a case of malignant pleural mesothelioma that developed 30 years after the patient underwent radiotherapy for breast cancer. This appears to be the first such case reported in the radiology literature.     

The pleural tail sign.

The pleural tail sign is widely thought to indicate malignancy. However, of 18 patients with the tail sign, 9 had benign disease. Bronchioloalveolar carcinoma was the most common malignant tumor, but adenocarcinoma, squamous-cell carcinoma, and metastatic adenocarcinoma of the colon were also found. The location of nodules and the radiographic characteristics of the pleural tails did not help differentiate benign from malignant lesions. However, nodules 2 cm or larger were malignant while those 1 cm or smaller were benign. Histologically, pleural tails reflected thickened, fibrotic connective tissue septae with indrawing of the visceral pleura. Their occurrence with neoplasm reflects desmoplastic reaction or scar carcinoma.     

Sonography of malignant pleural effusion

Two hundred and ten patients with exudative pleural effusion were studied by ultrasound for sonographic signs of pleural carcinomatosis. Images were evaluated for echoes within the fluid, septations, sheet-like or nodular pleural masses, and associated lesions of the lung. Our results showed that sonographic findings of echogenic or septated fluid were unspecific for malignancy. Only the evidence of pleural masses was characteristic of malignant effusion. Ultrasound of the chest should therefore be carried out before invasive diagnostic procedures are planned. Received 31 May 1995; Revision received 12 September 1996; Accepted 14 January 1997     

Diffusion-weighted MR imaging of pleural fluid: differentiation of transudative vs exudative pleural effusions

The aim of this study was to evaluate the ability of diffusion-weighted MRI in differentiating transudative from exudative pleural effusions. Fifty-seven patients with pleural effusion were studied. Diffusion-weighted imaging (DWI) was performed with an echo-planar imaging (EPI) sequence (b values 0, 1000 s/mm²) in 52 patients. The apparent diffusion coefficient (ADC) values were reconstructed from three different regions. Subsequently, thoracentesis was performed and the pleural fluid was analyzed. Laboratory results revealed 20 transudative and 32 exudative effusions. Transudates had a mean ADC value of 3.42±0.76×10^–3 mm²/s. Exudates had a mean ADC value of 3.18±1.82×10^–3 mm²/s. The optimum cutoff point for ADC values was 3.38×10^–3 mm²/s with a sensitivity of 90.6% and specificity of 85%. A significant negative correlation was seen between ADC values and pleural fluid protein, albumin concentrations and lactate dehydrogenase (LDH) measurements (r=–0.69, –0.66, and –0.46, respectively; p<0.01). The positive predictive value, negative predictive value, and diagnostic accuracy of ADC values were determined to be 90.6, 85, and 88.5%, respectively. The application of diffusion gradients to analyze pleural fluid may be an alternative to the thoracentesis. Non-invasive characterization of a pleural effusion by means of DWI with single-shot EPI technique may obviate the need for thoracentesis with its associated patient morbidity.