Fig. 4.64 Interstitial edema, note the fine interstitial markings in increasing opacifying lungs. Note adequately placed ET and NG tubes. Right IJ line in SVC (rotated projection)

Pulmonary Venous Congestion: Edema

Figure 4.64 depicts a diffuse, fine reticular pattern with a differential diagnosis of exudates, transudate, hemorrhage, secretions, or malignancy. Although not a vascular pattern, the interstitial pattern is compatible with ARDS.

Emphysema

Although not primarily a vascular condition, emphysema can cause extrinsic pressure to vasculature, causing a compressed and distorted appearance to the pulmonary vasculature in the apicies leading to this diagnosis.

Figure 4.65a provides an example of compressed vessels; decreased diameter of vessels is caused by excessive air pressure around them.

Findings: Upper lobe diminished and distorted vessels. Pattern: Vascular.

Differential Diagnosis: Bullous emphysema, COPD.

Airway (Bronchial) Patterns

For a brief description and graphic of normal airways, see the normal lung markings page of this book.

Mechanisms

•Complete or partial obstruction of airways

•Thickening of airway walls

•Atelectasis literally means incomplete expansion or loss of volume