stenosis

Stenosis is the abnormal narrowing or constriction of a duct, vessel, or opening in the body. This constriction can impede the flow of blood, bile, urine, air, or cerebrospinal fluid, depending on the site. Stenosis can be congenital or acquired and may result from processes such as atherosclerosis, scar tissue from injury or surgery, inflammation, tumors, or external compression.

Common forms include arterial stenosis, such as carotid or renal artery stenosis; aortic or other heart valve stenosis; spinal stenosis; and ureteral or biliary stenosis. Spinal stenosis narrows the spinal canal and may compress nerve roots, while aortic stenosis restricts blood flow from the heart. Other examples affect the urinary or biliary systems, producing obstruction and related symptoms.

Symptoms depend on location. Arterial stenosis may cause chest pain, leg pain with activity, or neurological symptoms from cerebral ischemia. Spinal stenosis often presents with back or neck pain and leg symptoms that worsen with walking. Ureteral stenosis can cause flank pain or obstructive urinary symptoms, and biliary stenosis can lead to jaundice or abdominal discomfort. Diagnosis uses imaging and functional studies tailored to the suspected site, including ultrasound with Doppler, CT or MR angiography, echocardiography, endoscopy, or catheter angiography.

Treatment ranges from risk-factor modification and medical therapy to interventional and surgical procedures. Endovascular options include angioplasty with or without stenting. Surgical approaches include endarterectomy for certain arterial narrowings, valve repair or replacement for valvular stenosis, decompression for spinal stenosis, and drainage or bypass procedures as needed. The choice depends on severity, symptoms, and overall health.

Prognosis varies with location and severity; early detection and appropriate treatment improve outcomes.