Intramural bowel gas
Intramural bowel gas, also known as pneumatosis intestinalis, refers to gas within the wall of the bowel.
There are different terminologies in the medical literature, such as pneumatosis intestinalis, pneumatosis coli, and pneumatosis cystoides intestinalis. Pneumatosis coli is used when only the colic wall is involved, and is generally an incidental finding in asymptomatic patients. Pneumatosis cystoides intestinalis is descriptive for multiple gaseous cysts along the bowel wall.
Intramural gas can be seen in intestinal ischaemia and eventually bowel infarction. This is the most concerning etiology for intramural gas.
Gas in the bowel wall in the neonatal period, whatever its shape, is diagnostic of necrotising enterocolitis.
Asymptomatic pneumatosis intestinalis may result from a variety of interrelated contributing factors including
- mucosal integrity
- intraluminal pressure
- bacterial flora
- intraluminal gas
Gas tracks along the bowel wall, appearing as either linear (usually submucosal) or rounded cystic collections (usually subserosal) 1.
- bowel ischaemia and infarction
- autoimmune disease
From a clinical perspective, it is essential not to confuse the incidental imaging finding of asymptomatic pneumatosis with symptomatic colonic perforation because the treatment is significantly different 2.
- 1. Devos AS, Blickman JG, Blickman JG. Radiological Imaging of the Digestive Tract in Infants and Children. Springer Verlag. (2007) ISBN:3540407332. Read it at Google Books - Find it at Amazon
- 2. Pickhardt PJ, Kim DH, Taylor AJ. Asymptomatic pneumatosis at CT colonography: a benign self-limited imaging finding distinct from perforation. AJR Am J Roentgenol. 2008;190 (2): W112-7. doi:10.2214/AJR.07.2843 - Pubmed citation
- 3. Ho LM, Paulson EK, Thompson WM. Pneumatosis intestinalis in the adult: benign to life-threatening causes. AJR Am J Roentgenol. 2007;188 (6): 1604-13. doi:10.2214/AJR.06.1309 - Pubmed citation