Radiographic changes in a patient with emphysema:
(1) flat horizontal diaphragm that is located lower than normal:
(1a) blunting of the costophrenic angles in the PA view
(1b) sternodiaphragmatic angle 90° or greater in the lateral view
(2) widening of the intercostals spaces
(3) enlarged retrosternal space (>= 2.5 cm) in front of the ascending aorta in the lateral view
(4) "saber sheath" trachea (marked coronal narrowing with sagittal widening)
(5) irregular and increased radiolucency of the lung fields
(6) enlargement of the pulmonary conus and hilar pulmonary arteries
(7) decreased diameter and apparent number of peripheral blood vessels (vascular attenuation)
(8) increased markings of the bronchovascular shadows in the lower lobes
Limitations:
• The routine chest X-ray is insensitive for early emphysema and can be nonspecific.
• Quantitative analysis of high resolution CT scans of the lungs is a more sensitive and specific method for evaluating a patient for emphysema.
