A stricture is an abnormal narrowing of a hollow passage in the body, most commonly in the esophagus (food pipe), urethra (urinary tract), or intestines. The narrowing happens when chronic inflammation damages the lining of the passage and triggers a buildup of scar tissue, gradually shrinking the opening and making it harder for food, urine, or other contents to pass through normally.
How Strictures Form
Strictures develop through a process that starts with repeated or ongoing injury to the inner lining of a body passage. When tissue is damaged, the body sends repair cells to the area. In normal healing, these cells lay down a temporary scaffold of new tissue, then the process resolves. In stricture formation, something goes wrong with this cycle.
Chronic inflammation keeps activating specialized repair cells called myofibroblasts. These cells produce collagen, a structural protein that forms scar tissue. Normally, the body balances new collagen production with the breakdown of old collagen. But when inflammation persists, this balance tips. The repair cells begin operating independently of the original inflammatory signals, creating a self-sustaining loop: new scar tissue is deposited, partially broken down, then replaced with even more scar tissue. Over time, this results in a net accumulation of dense, inflexible tissue in the wall of the passage. The muscle layers around the passage also thicken, with individual muscle cells growing both larger and more numerous. The combined effect is a passage that has physically narrowed and lost its ability to stretch open.
Where Strictures Commonly Occur
Esophageal Strictures
The esophagus is one of the most common sites. Long-standing acid reflux is a frequent cause: stomach acid repeatedly irritates the esophageal lining, triggering the inflammation-to-scarring progression described above. Other causes include swallowing corrosive substances, radiation therapy to the chest, and a condition called eosinophilic esophagitis, where immune cells accumulate in the esophageal wall. The hallmark symptom is difficulty swallowing, which typically starts with solid foods like bread or meat and may progress to softer foods as the narrowing worsens. A stricture can be localized to one spot or spread across a longer segment of the esophagus, and its edges can be either abrupt or gradually tapered.
Urethral Strictures
In the urethra, strictures cause a weak or slow urine stream, painful urination, difficulty fully emptying the bladder, and sometimes painful ejaculation. Common causes include pelvic fractures or direct injury to the area between the legs, severe urinary tract infections, scarring from catheter placement, radiation therapy, and previous urologic surgery. In many cases, no clear cause is ever identified. Urethral strictures can develop at any age.
Intestinal Strictures
Crohn’s disease is the leading cause of intestinal strictures. The chronic, recurring inflammation characteristic of Crohn’s damages the bowel wall over time, with scar tissue and collagen building up particularly in the deeper layers. An important distinction exists here: some intestinal strictures are predominantly inflammatory, meaning active swelling is the main reason for the narrowing, while others are predominantly fibrotic, meaning dense scar tissue is the primary problem. Most advanced strictures contain both components. This distinction matters because inflammatory strictures may respond to medications that reduce inflammation, while fibrotic strictures generally require a physical intervention like dilation or surgery.
How Strictures Are Diagnosed
For esophageal strictures, upper endoscopy is typically the first test. A thin, flexible camera is passed down the throat to directly visualize the narrowing. However, endoscopy can miss subtle strictures. A barium swallow study, where you drink a contrast liquid and then have X-rays taken as it travels down the esophagus, identified structural abnormalities in 50% of patients whose endoscopy appeared completely normal in one retrospective review. The two tests complement each other: endoscopy allows tissue sampling and immediate treatment, while the barium swallow is better at detecting mild narrowing and problems with how the esophagus moves.
Urethral strictures are typically diagnosed with imaging that involves injecting contrast dye into the urethra, or with a small camera passed into the urinary tract. For intestinal strictures in Crohn’s disease, CT scans and MRI are standard tools, and newer imaging techniques can help distinguish inflammatory from fibrotic tissue to guide treatment decisions.
Treatment Options
Dilation
The most common treatment for esophageal strictures is dilation, a procedure done during endoscopy to physically stretch the narrowed area open. Two main techniques exist. Bougie dilation involves passing progressively thicker flexible tubes through the narrowing, applying force along the length of the stricture. Balloon dilation involves positioning a deflated balloon at the exact point of narrowing, then inflating it to push the walls outward with radial pressure.
Both methods provide equivalent symptom relief and have similar rates of recurrence, bleeding, and perforation. Balloon dilation does cause significantly less pain after the procedure. The overall risk of serious complications is low: perforation occurs in roughly 0.5% of all dilation procedures, and in some patient populations the rate is as low as 0.1%. Most patients notice improved swallowing immediately, though multiple sessions may be needed over time if the stricture recurs.
Surgery
For urethral strictures, initial treatment often involves simple dilation or an internal cutting procedure. These work best for short strictures under 2 centimeters and offer equivalent results to each other for first-time treatment. However, repeated dilations and repeat procedures have poor long-term outcomes. For strictures longer than 4 centimeters, or those that return after initial treatment, surgical reconstruction (urethroplasty) is considered the best option by most urologists in Europe and the United States.
Intestinal strictures that are predominantly fibrotic and don’t respond to medical therapy may be treated with balloon dilation during a colonoscopy, or with surgery to remove the narrowed segment of bowel.
Living With a Stricture
If you have an esophageal stricture that hasn’t been fully resolved, or you’re recovering from a dilation procedure, food texture matters. An international framework for modified food textures provides a useful guide. At the most restrictive end, puréed foods like mashed potato, blended vegetables, and smooth soups require no chewing and pass through a narrowed esophagus more easily. As tolerance improves, you can progress to minced and moist foods (small pieces no larger than 2 to 4 millimeters), then to soft foods that can be mashed with a fork, like cooked tender meat, steamed vegetables, and flaked fish. The goal is to work back toward regular textures as the stricture is treated and swallowing improves.
Practical tips that help: eating slowly, taking small bites, chewing thoroughly, and drinking fluids with meals to help food pass. Dry, tough, or fibrous foods like crusty bread, raw vegetables, and stringy meats tend to be the most problematic and are worth avoiding until your swallowing has been evaluated.
For urethral strictures, the main day-to-day concern is monitoring your urinary stream. A noticeably weaker flow, straining to urinate, or feeling like your bladder isn’t emptying completely are signs the stricture may be worsening or recurring after treatment.