outpouchings

Outpouchings are pouch-like projections from a hollow organ wall into the lumen or surrounding space. They may involve all layers of the wall (true diverticula) or consist of mucosa and submucosa herniating through the muscularis (false or pseudodiverticula). The term applies in many systems, most notably the gastrointestinal and genitourinary tracts.

In the gastrointestinal tract, colonic diverticula are the most familiar. They are usually false diverticula formed as mucosa and submucosa herniate through the muscular wall at vessel points, linked to increased intraluminal pressure. Esophageal diverticula occur as pulsion or traction lesions, with Zenker’s diverticulum being a well-known example. Small bowel diverticula are less common. In the genitourinary tract, bladder diverticula may be congenital or acquired, often due to obstruction or chronic pressure.

Most outpouchings are asymptomatic. When symptoms occur, they depend on location and may include dysphagia or abdominal discomfort. Complications include inflammation (diverticulitis), bleeding, perforation, obstruction, or stone formation within the pouch.

Diagnosis relies on imaging and endoscopy targeted to the site, such as CT, ultrasound, barium studies, or endoscopy. Management ranges from observation for incidental lesions to treatment of complications. Diverticulitis is usually treated with antibiotics and supportive care; complicated cases may require surgery or endoscopic intervention. Prognosis varies with location and comorbidity.