Subcutaneous emphysema after associated colonoscopy and transanal excision of rectal adenoma.

Non-traumatic subcutaneous emphysema (NSE) is a rare complication of procedures of the digestive tract. To the best of our knowledge, it has never been reported to occur after transanal surgery. Herein we present the first known case of NSE accompanied by retropneumoperitoneum and pneumomediastinum to develop after colonoscopy and full-thickness transanal removal of a rectal polyp.