The lung apex is the very top of the lung. The lung apex is in the upper lobes of the lungs. A characteristic set of abnormalities is found here, although many common conditions like pneumonia and cancer can also be found. This area can be hard to evaluate well on X-rays because of overlying bones like the clavicle, ribs and blood vessels.
What common conditions happen at the lung apex?
Pneumonia of the lung apex
Pneumonia is perhaps the most common abnormality found here. This is an infection of the lungs with filling of the airspaces of the lungs with pus and fluid. Often the pneumonia extends to other regions and involves other segments of the lung.
Cancer of the lung apex
Cancer in the lung apex is called a pancoast tumor. This may invove the ribs and soft tissues above the lung.
What are some less common abnormalities in the lung apex?
Sarcoidosis that involves the lung apex
Sarcoidosis is a an inflammatory disease of unknown cause that involves multiple organs and body regions. Most patients have lung involvement. Typically there is involvement of the upper lungs and apices. There are enlarged lymph nodes. Complications can include scarring of the lungs, pulmonary hypertension and infections of the lung.
Tuberculosis of the lung apex
Tuberculosis infection also classically involves the upper lungs and apices. This is most commonly seen after the infection reactivates after a long period of remission. There can be cavities, lung opacities and enlarged lymph nodes. Military tuberculosis occurs when the infection spreads throughout the body. It is most easily detected on imaging in the lungs as numerous small spots or nodules.
Radiation injury of the lung apex
Radiation injury for patients undergoing treatment for cancer is also common in the upper lungs and apices. In the first 3 months, patients may develop radiation pneumonitis, which is more of an acute lung injury. Months later, they can develop fibrosis or scarring of the lungs. Many people also have benign scarring of the apices which can occur for reasons unknown. This can mimic radiation treatment although there is no history of this.
Allergic lung disease
Allergic lung disease often involves the upper lungs and apices. Patients often present with cough and shortness of breath. This can be induced by numerous external antigens like birds, metal workers, microbes, plant proteins in addition to others. The lungs can have infiltrates and scarring involving the upper lungs and apices. Removal of the offending antigen is critical to treatment.
The lung apex is the very top of the lung. This is a place for some characteristic conditions described above. The location of the abnormality and clinical history allows the radiologist to narrow the diagnostic possibilities. The imaging appearance overlaps with many conditions. Scarring, pneumonia, and cancer can have similar appearances. Stability over prior exams, clinical history and possible further testing allow us to reach a more confident diagnosis.