An 18 y/o male presented to the ED with chest and back pain that started in the center of his chest, then moved to left scapula. Pain was sharp and worse with deep inspiration. His only associated symptoms was anxiety. No risk factors for heart disease, PE. 

VS: 101 20 136/88 20 99%

PE: normal

EKG: normal

CXR Findings: PA and lateral views of the chest are presented for interpretation. No prior studies

are available for comparison. The heart size is normal. The trachea is midline. The lung fields

are clear.

Impression: Radiographically negative chest.

Pt was discharged, symptoms persisted, so he went to another institution where he was admitted. Why? Look carefully at his cxr below

As you've probably noticed, the radiologist misread the film- or dictated onto the wrong chart, or made some other mistake that we're all capable of making.  So this case serves as both a reminder to get into the habit of looking at all your own films, and a review of a neat CXR finding.  

The patient has a pneumomediastinum   and pneumothorax

with deep sulcus.

Spontaneous pneumomediastium is fairly rare. It occurs when air leaks out of a ruptured alveola and tracks along the bronchovascular sheath until it reaches the mediastinum. Air can also track to the pleural space, as in this case, or into the subQ tissues, submandibular and retropharyngeal space, or even into the spinal canal (see Dr. Permar for more information on this complication). Triggering factors can usually be identified but  are so common (crying, Valsalva, coughing, vomiting) that they don't rule in the disease.

The most common presenting symptoms will be pain wherever the air has tracked. Physical examination will likely be normal with isolated pneumomediastinum, although you may be lucky enough to hear Hamman's  crunch (crepitus heard over the heart). You may feel subcutaneous emphysema if the air has tracked there. Patient's with large pneumothoraces may have decreased breath sounds or hypoxia. 

Spontaneous pneumomediastinum is generally a self-limited disease without serious sequelae- much different than if caused by Boerhaave's or trauma. It requires no treatment except analgesia as needed. This patient was admitted for treatment of his pneumothorax.