Learning objectives
* To describe the imaging features (X-Ray, CT, IRM, and US) normal air/gas in the different tissues and potential body spaces.
* To identify the origin of air/gas and distribution patterns (intracerebral, intravascular, intraspinal, mediastinal, extrapleural, solid viscera, peritoneal cavity, intraarticular, soft tissues ) associated with the different pathologic entities.
*To analyze abnormal gas location in order to detect situations that involve high mortality rate, requiring emergent medical treatment or surgical management.
Background
Gas is a normal and common sign in imaging in different body tissues and internal cavities. Usually, it can be a benign incidental find, but in other cases may disclose life-threatening pathology. Abnormal gas can be found from trauma, iatrogenic injuries, interventional procedures or infection to inflammation.
1. HOW IS GAS SHOWN IN EACH IMAGING TECHNIQUE?
The air is one of the five basicradiographic densities: (air, fat, water, bone, and metal) and constitutes a physiological and pathological marker. It is its location that indicates whether...
Findings and procedure details
3. ABNORMAL GAS LOCATION. SHOULD I WORRY?
Clinical manifestations and prognosis can vary from benign cases in which we can consider that gas is not worrisome, to life-threatening situations in which urgent surgery is needed. For this reason, when ectopic gas is found, we must ask ourselves two questions: where does it come from and whether or not it is an alarming finding.
We should remember that gas can dissect between different body spaces as a result of this fascial interconnectivity, distant from its source...
Conclusion
An effort should be made by the radiologist to identify ectopic air/gas, to determine the probable source and recognizing the entities related with this diagnostic imaging hallmark. In some circumstances, a little bubble in an abnormal location might provide us the diagnostic key.
Remember:
KEEP THE EYE ON THE BUBBLE!
Personal information and conflict of interest
L. Zambrana Aguilar; Almería/ES - nothing to disclose J. L. Rueda-Vicente; Almería/ES - nothing to disclose C. M. Martinez Porras; Almería/ES - nothing to disclose M. A. Garcia-Espona; Almería/ES - nothing to disclose
References
Dahnert W. Radiology Review Manual 3rd ed. Baltimore, Md: Williams & Wilkins, 1996.
Sandstrom, C.K., Osman, S.F. & Linnau, K.F. Scary gas: a spectrum of soft tissue gas encountered in the axial body (part II).Emerg Radiol(2017) 24,401–409
Sandstrom, C.K., Osman, S.F. & Linnau, K.F. Scary gas: intravascular, intracranial, and intraspinal ectopic gas (part III) Emerg Radiol (2017) 24: 411
Randstrom, C.K., Osman, S.F. & Linnau, K.F. Scary gas: pathways in the axial body for soft tissue gas dissection (part I). Emerg Radiol (2017) 24: 569...