Role of Computed Tomography In Diagnosis of pleural Lesions

Abstract

The main pleural disorders are : effusion ,thickening masses and pneumothorax. Chest radiography is the first approach for evaluation of pleural disease, computed tomography is an ideal method for assessment of pleural lesions , because it allows cross sectional imaging thus overcoming the problem of overlapping densities on plain X-ray. C.T is particularly helpful in the assessment of loculated pleural effusions.

With the possible exception of hemithorax , measurement of fluid attenuation coefficients has proved unreliable in distinguishing fluid composition.

Contrast-enhanced C.T may help in the diagnosis of pleural transudates and exudates by demonstrating enhancing parietal thickening , which almost always indicates pleural exudates.

C.T can help in assessment of unexplained pleural effusion by establishment of benign versus malignant cause. The presence of pleural abnormalities in the from of thickened, irregular contrast enhanced pleura with or without discrete masses arouse the suspicion of possible malignancy involving the pleura. But , absence of those abnormalities dose not rule out pleural malignancy. C.T plays a major role in diagnosis of empyema. Not only C.T can help in the assessment of presence of empyema, but also, is the best method to differentiate empyemas from peripheral pulmonary abscesses. C.T is of proven efficancy for assessing the response of patients to therapy .