Solitary Lucent Defect
Abstract A solitary lucent defect may result from a necrotic cavity, cyst, pneumatocele, or a loculated hydropneumothorax, but of these possibilities, a necrotic cavity is the most common. A necrotic…
Solitary Pulmonary Nodule
Abstract The solitary pulmonary nodule is a common challenge for the radiologist. Size, location, and attenuation are important characteristics in determining perception and detectability of a nodule. Computed tomography (CT)…
Multiple Lucent Lesions
Abstract Multiple lucent lesions are most often the result of infectious diseases. Multiple cavities frequently complicate virulent bacterial, tuberculous, and parasitic or fungal infections. Septic emboli cause multiple cavities that…
Hyperlucent Thorax
Abstract Pneumothorax is the most urgent cause of a hyperlucent thorax. Pneumothorax has a variety of causes ranging from trauma to rupture of pulmonary cavities, cysts, or bullae into the…
Multiple Nodules and Masses
Abstract Multiple pulmonary nodules are most often metastases from a distant primary tumor, but they must be distinguished from a number of inflammatory and infectious diseases that may cause multiple…
Multifocal Ill-Defined Opacities
Abstract Multifocal ill-defined opacities most often result from multiple consolidations but must be distinguished from invasive or hemorrhagic tumors. This is not a common appearance for community-acquired pneumonia, but when…
Diffuse Fine Nodular Opacities
Abstract Diffuse fine nodules are the expected presentation of intravascular dissemination of tuberculosis, which is a life-threatening complication. Perception of the fine nodular opacities is often difficult and may require…
Fine Reticular Opacities
Abstract Fine reticular opacities are reliable evidence of interstitial lung disease that requires consideration of a variety of acute and chronic diseases. Acute interstitial disease is most often the result…
Coarse Reticular Opacities (Honeycomb Lung)
Abstract Coarse reticular opacities are the result of lung destruction caused by retracting fibrosis, which also produces cystic spaces. This combination of coarse reticular opacities and cystic spaces is better…
Atelectasis
Abstract Atelectasis is loss of lung volume and a very common observation, with an appearance on the chest x-ray that is often nonspecific, but shift of normal structures may confirm…
