Imaging

Those who care for patients with pulmonary, critical care or sleep disorders rely heavily on chest radiology and pathology to determine diagnoses. The Southwest Journal of Pulmonary, Critical Care & Sleep publishes case-based articles with characteristic chest imaging and related pathology.

The editor of this section will oversee and coordinate the publication of a core of the most important chest imaging topics. In doing so, they encourage the submission of unsolicited manuscripts. It cannot be overemphasized that both radiologic and pathologic images must be of excellent quality. As a rule, 600 DPI is sufficient for radiographic and pathologic images. Taking pictures of plain chest radiographs and CT scans with a digital camera is strongly discouraged. The figures should be cited in the text and numbered consecutively. The stain used for pathology specimens and magnification should be mentioned in the figure legend. Those who care for patients with pulmonary, critical care or sleep disorders rely heavily on chest radiology and pathology to determine diagnoses. The Southwest Journal of Pulmonary, Critical Care & Sleep publishes case-based articles with characteristic chest imaging and related pathology. The editor of this section will oversee and coordinate the publication of a core of the most important chest imaging topics. In doing so, they encourage the submission of unsolicited manuscripts. It cannot be overemphasized that both radiologic and pathologic images must be of excellent quality. As a rule, 600 DPI is sufficient for radiographic and pathologic images. Taking pictures of plain chest radiographs and CT scans with a digital camera is strongly discouraged. The figures should be cited in the text and numbered consecutively. The stain used for pathology specimens and magnification should be mentioned in the figure legend.

Rick Robbins, M.D. 1/8/14 Rick Robbins, M.D. 1/8/14

Medical Image of the Week: Pneumomediastinum

Figure 1. Chest x-ray (CXR) shows subtle evidence of pneumomediastinum with air outlining left cardiac border and trachea (arrows).

Figure 2. Chest computerized tomography (CT) showing pneumomediastinum (Panel A) extending into lower neck (Panel B) without evidence of pneumothorax.

A 65 year old man presented with mild increase in shortness of breath. He had a past medical history of diabetes mellitus, hypertension, and severe malnutrition with percutaneous endoscopic gastrostomy (PEG) placement after a colectomy and end ileostomy for sigmoid volvulus. CXR (Figure 1) suggested a pneumomediastinum with subsequent chest CT (Figure 2) confirming moderate sized pneumomediastinum. He had a chronic cough from chronic obstructive pulmonary disease (COPD) as well as aspiration and chest CT also demonstrated emphysema with small blebs. He denied any significant chest pain. He was followed conservatively with imaging and discharged in stable condition.

Pneumomediastinum can be caused by trauma, esophageal rupture after vomiting (Boerhaave’s syndrome) and can be a spontaneous event if no obvious precipitating cause is identified (1). Valsalva maneuvers such as cough, sneeze, vomiting and childbirth, can all cause pneumomediastinum. Risk factors include asthma, COPD, interstitial lung disease and inhalational recreational drug use. Hamman's sign (a crunching sound in time with the heartbeat) can occasionally be heard. More commonly, subcutaneous emphysema is felt on exam (crepitus). Complications can include single or bilateral pneumothorax, tension pneumothorax and pleural effusion. CXR often does not identify mediastinal air and CT imaging is highly sensitive and confirmatory. Conservative management is recommended with close clinical follow up for possible complications.

Rene Franco, Jr MD, Mohammad Dalabih MD, Janet Campion MD

University of Arizona Medical Center, Tucson AZ

Reference

Newcomb AE, Clarke CP. Spontaneous Pneumomediastinum. Chest. 2005;128:3298-3302. [CrossRef] [PubMed]

Reference as: Franco R Jr, Dalabih M, Campion J. Medical image of the week: pneumomediastinum. Southwest J Pulm Crit Care. 2014:8(1):46-7. doi: http://dx.doi.org/10.13175/swjpcc160-13 PDF