Laryngotracheal stenosis is an umbrella term for a wide and heterogeneous group of very rare conditions. The population incidence of adult post-intubation laryngotracheal stenosis which is the commonest benign sub-type of this condition is approximately 1 in 200,000 adults per year. The main causes of adult laryngotracheal stenosis are:

The optimal management of laryngotracheal stenosis is not well defined, depending mainly on the type of the stenosis.

General treatment options include

1. Tracheal dilation using rigid bronchoscope

2. Laser surgery and endoluminal stenting

3. Tracheal resection and laryngotracheal reconstructionr

Tracheal is used to temporarily enlarge the airway. The effect of dilation typically lasts from a few days to 6 months. Several studies have shown that as a result of mechanical dilation (used alone) may occur a high mortality rate and a rate of recurrence of stenosis higher than 90%.

Thus, many authors treat the stenosis by endoscopic excision with laser (commonly either the carbon dioxide or the neodymium: yttrium aluminum garnet laser) and then by using bronchoscopic dilatation and prolonged stenting with a T-tube (generally in silicone).

There are differing opinions on treating with laser surgery.

In very experienced surgery centers, tracheal resection and reconstruction (anastomosis complete end-to-end with or without laryngotracheal temporary stent to prevent airway collapse) is currently the best alternative to completely cure the stenosis and allows to obtain good results. Therefore, it can be considered the gold standard treatment and is suitable for almost all patients.

The narrowed part of the trachea will be cut off and the cut ends of the trachea sewn together with sutures. For stenosis of length greater than 5 cm a stent may be required to join the sections.

Late June or early July 2010, a new potential treatment was trialed at Great Ormond Street Hospital in London, where Ciaran Finn-Lynch (aged 11) received a transplanted trachea which had been injected with stem cells harvested from his own bone marrow. The use of Ciaran's stem cells was hoped to prevent his immune system from rejecting the transplant, but there remain doubts about the operation's success, and several later attempts at similar surgery have been unsuccessful.

Diagnosis is via a careful history and physical examination, often supplemented by radiographic imaging studies. Pyloric stenosis should be suspected in any young infant with severe vomiting. On physical exam, palpation of the abdomen may reveal a mass in the epigastrium. This mass, which consists of the enlarged pylorus, is referred to as the 'olive', and is sometimes evident after the infant is given formula to drink. Rarely, there are peristaltic waves that may be felt or seen (video on NEJM) due to the stomach trying to force its contents past the narrowed pyloric outlet.

Most cases of pyloric stenosis are diagnosed/confirmed with ultrasound, if available, showing the thickened pylorus and non-passage of gastric contents into the proximal duodenum. Muscle wall thickness 3 millimeters (mm) or greater and pyloric channel length of 15 mm or greater are considered abnormal in infants younger than 30 days.

Although somewhat less useful, an upper GI series (x-rays taken after the baby drinks a special contrast agent) can be diagnostic by showing the narrowed pyloric outlet filled with a thin stream of contrast material; a "string sign" or the "railroad track sign". For either type of study, there are specific measurement criteria used to identify the abnormal results. Plain x-rays of the abdomen sometimes shows a dilated stomach.

Although UGI endoscopy would demonstrate pyloric obstruction, physicians would find it difficult to differentiate accurately between hypertrophic pyloric stenosis and pylorospasm.

Blood tests will reveal low blood levels of potassium and chloride in association with an increased blood pH and high blood bicarbonate level due to loss of stomach acid (which contains hydrochloric acid) from persistent vomiting. There will be exchange of extracellular potassium with intracellular hydrogen ions in an attempt to correct the pH imbalance. These findings can be seen with severe vomiting from any cause.

Subglottic stenosis is a congenital or acquired narrowing of the subglottic airway. Although it is relatively rare, it is the third most common congenital airway problem (after laryngomalacia and vocal cord paralysis). Subglottic stenosis can present as a life-threatening airway emergency. It is imperative that the otolaryngologist be an expert at dealing with the diagnosis and management of this disorder. Subglottic stenosis can affect both children and adults.

Subglottic stenosis can be of three forms, namely congenital subglottic stenosis, idiopathic subglottic stenosis (ISS) and acquired subglottic stenosis. As the name suggests, congenital subglottic stenosis is a birth defect. Idiopathic subglottic stenosis is a narrowing of the airway due to an unknown cause. Acquired subglottic stenosis generally follows as an after-effect of airway intubation, and in extremely rare cases as a result of gastroesophageal reflux disease (GERD).

Subglottic stenosis is graded according to the Cotton-Meyer classification system from one to four based on the severity of the blockage.

Grade 1 – <50% obstruction

Grade 2 – 51–70% obstruction

Grade 3 – 71–99% obstruction

Grade 4 – no detectable lumen

Treatments to alleviate the symptoms of subglottic stenosis includes a daily dose of steroids such as prednisone, which reduces the inflammation of the area for better breathing. Other medications such as Methotrexate is also being tested by patients but results are pending.

Phase contrast-MRI is an imaging method which is more sensitive than MRI for analysis of the pulsatile CSF flow in the ventricular system. This method takes multiple images of the ventricles within one cardiac cycle to measure the flow of CSF running past the area of acquisition. If no flow is seen, this is a reliable diagnosis of aqueductal stenosis as it implies that there is a blockage of CSF.

Ultrasonography can be used in utero to diagnose aqueductal stenosis by showing dilation of the lateral and third ventricles. A retrospective study found that diagnosis can be made as early as 19 weeks of gestation, and that on average diagnosis is made at 33 weeks. Unfortunately, prenatal diagnosis still has a poor prognosis even with immediate treatment upon birth.

MRI is considered the best method of detecting aqueductal stensosis because it can visualize the entire length of the aqueduct, can clearly depict tumors, and can show ventricle enlargement or other deformations. It is helpful in determining the extent of the aqueductal obstruction, particularly when multiple masses or lesions are present, and thereby aids in determining the most appropriate treatment method (i.e. surgery, shunt, or ETV). When constructive interference in steady state (CISS) or fast imaging employing steady-state acquisition (FIESTA) sequence are used, subtle abnormalities or partial obstructions in the aqueduct can be depicted in the MRI. For example, CISS can be used to determine if a thin membrane interfering with CSF flow is present.

Vessel restenosis is typically detected by angiography, but can also be detected by duplex ultrasound and other imaging techniques.

Infantile pyloric stenosis is typically managed with surgery; very few cases are mild enough to be treated medically.

The danger of pyloric stenosis comes from the dehydration and electrolyte disturbance rather than the underlying problem itself. Therefore, the baby must be initially stabilized by correcting the dehydration and the abnormally high blood pH seen in combination with low chloride levels with IV fluids. This can usually be accomplished in about 24–48 hours.

Intravenous and oral atropine may be used to treat pyloric stenosis. It has a success rate of 85-89% compared to nearly 100% for pyloromyotomy, however it requires prolonged hospitalization, skilled nursing and careful follow up during treatment. It might be an alternative to surgery in children who have contraindications for anesthesia or surgery, or in children whose parents do not want surgery.

The diagnosis of pulmonary valve stenosis can be achieved via echocardiogram, as well as a variety of other means among them are: ultrasound, in which images of the heart chambers in utero where the tricuspid valve has thickening (or due to Fallot's tetralogy, Noonan's syndrome, and other congenital defects) and in infancy auscultation of the heart can reveal identification of a murmur.

Some other conditions to contemplate (in diagnosis of pulmonic valvular stenosis) are the following:

- Infundibular stenosis

- Supravalvular pulmonary stenosis

- Dysplastic pulmonic valve stenosis

In terms of treatment for pulmonary valve stenosis, valve replacement or surgical repair (depending upon whether the stenosis is in the valve or vessel) may be indicated. If the valve stenosis is of congenital origin, balloon valvuloplasty is another option, depending on the case.

Valves made from animal or human tissue (are used for valve replacement), in adults metal valves can be used.

In boys, history and physical exam is adequate to make the diagnosis. In girls, VCUG (voiding cystourethrogram) is usually diagnostic. Other tests may include:

- Urine analysis

- Urine culture

- CBC, basic metabolic panel

- Renal and bladder ultrasound

In peripheral procedures, rates are still high. A 2003 study of selective and systematic stenting for limb-threatening ischemia reported restenosis rates at 1 year follow-up in 32.3% of selective stenting patients and 34.7% of systematic stenting patients.

The 2006 SIROCCO trial compared the sirolimus drug-eluting stent with a bare nitinol stent for atherosclerotic lesions of the superficial femoral artery, reporting restenosis at 2 year follow-up was 22.9% and 21.1%, respectively.

A 2009 study compared bare nitinol stents with percutaneous transluminal angioplasty (PTA) in superficial femoral artery disease. At 1 year follow-up, restenosis was reported in 34.4% of stented patients versus 61.1% of PTA patients.

In females, meatal stenosis can usually be treated in the physician's office using local anesthesia to numb the area and dilating (widening) the urethral opening with special instruments.

In boys, it is treated by a second surgical procedure called meatotomy in which the meatus is crushed with a straight mosquito hemostat and then divided with fine-tipped scissors. Recently, home-dilatation has been shown to be a successful treatment for most boys.

Stenoses of the vascular type are often associated with unusual blood sounds resulting from turbulent flow over the narrowed blood vessel. This sound can be made audible by a stethoscope, but diagnosis is generally made or confirmed with some form of medical imaging.

If untreated, severe symptomatic aortic stenosis carries a poor prognosis with a 2-year mortality rate of 50-60% and a 3-year survival rate of less than 30%. Prognosis after aortic valve replacement for people who are younger than 65 is about five years less than that of the general population; for people older than 65 it is about the same.

In 1977, Dyck and Doyle reported on the bicycle test, a simple procedure in which the patient is asked to pedal on a stationary bicycle. If the symptoms are caused by peripheral vascular disease, the patient will experience claudication, a sensation of not getting enough blood to the legs; if the symptoms are caused by lumbar stenosis, symptoms will be relieved when the patient is leaning forward while bicycling. Although diagnostic progress has been made with newer technical advances, the bicycle test remains an inexpensive and easy way to distinguish between claudication caused by vascular disease and spinal stenosis.

The resulting syndrome depends on the structure affected.

Examples of vascular stenotic lesions include:

- Intermittent claudication (peripheral artery stenosis)

- Angina (coronary artery stenosis)

- Carotid artery stenosis which predispose to (strokes and transient ischaemic episodes)

- Renal artery stenosis

The types of stenoses in heart valves are:

- Pulmonary valve stenosis, which is the thickening of the pulmonary valve, therefore causing narrowing

- Mitral valve stenosis, which is the thickening of the mitral valve (of the left heart), therefore causing narrowing

- Tricuspid valve stenosis, which is the thickening of the tricuspid valve (of the right heart), therefore causing narrowing

- Aortic valve stenosis, which is the thickening of the aortic valve, therefore causing narrowing

Stenoses/strictures of other bodily structures/organs include:

- Pyloric stenosis (gastric outflow obstruction)

- Lumbar, cervical or thoracic spinal stenosis

- Subglottic stenosis (SGS)

- Tracheal stenosis

- Obstructive jaundice (biliary tract stenosis)

- Bowel obstruction

- Phimosis

- Non-communicating hydrocephalus

- Stenosing tenosynovitis

- Atherosclerosis

- Esophageal stricture

- Achalasia

- Prinzmetal angina

- Vaginal stenosis

A spinal tap is performed in the low back with dye injected into the spinal fluid. X-Rays are performed followed by a CT scan of the spine to help see narrowing of the spinal canal.

This is a very effective study in cases of lateral recess stenosis. It is also necessary for patients in which MRI is contraindicated, such as those with implanted pacemakers.

MRI has become the most frequently used study to diagnose spinal stenosis. The MRI uses electromagnetic signals to produce images of the spine. MRIs are helpful because they show more structures, including nerves, muscles, and ligaments, than seen on x-rays or CT scans. MRIs are helpful at showing exactly what is causing spinal nerve compression.

The detection of spinal stenosis in the cervical, thoracic or lumbar spine confirms only the anatomic presence of a stenotic condition. This may or may not correlate with the diagnosis of spinal stenosis which is based on clinical findings of radiculopathy, neurogenic claudication, weakness, bowel and bladder dysfunction, spasticity, motor weakness, hyperreflexia and muscular atrophy. These findings, taken from the history and physical examination of the patient (along with the anatomic demonstration of stenosis with an MRI or CT scan), establish the diagnosis.

Heyde's syndrome is now known to be gastrointestinal bleeding from angiodysplasic lesions due to acquired vWD-2A deficiency secondary to aortic stenosis, and the diagnosis is made by confirming the presence of those three things. Gastrointestinal bleeding may present as bloody vomit, dark, tarry stool from metabolized blood, or fresh blood in the stool. In a person presenting with these symptoms, endoscopy, gastroscopy, and/or colonoscopy should be performed to confirm the presence of angiodysplasia. Aortic stenosis can be diagnosed by auscultation for characteristic heart sounds, particularly a crescendo-decrescendo (i.e., 'ejection') murmur, followed by echocardiography to measure aortic valve area (see diagnosis of aortic stenosis). While Heyde's syndrome may exist alone with no other symptoms of aortic stenosis, the person could also present with evidence of heart failure, fainting, or chest pain. Finally, Heyde's syndrome can be confirmed using blood tests for vWD-2A, although traditional blood tests for von Willebrand factor may result in false negatives due to the subtlety of the abnormality. The gold standard for diagnosis is gel electrophoresis; in people with vWD-2A, the large molecular weight von Willebrand factors will be absent from the SDS-agarose electrophoresis plate.

For diagnosis, measures of liver biochemistry and pancreatic enzymes are performed. Along with ruling out structural abnormalities, normally by performing an abdominal ultrasound and endoscopic retrograde cholangiopancreatography (ERCP). Measurements of bile transit when performing ERCP are taken to help evaluate different treatment options.

Sphincter of Oddi dysfunction is best diagnosed using manometry-an internal test done to measure the pressures within surrounding ducts to determine whether or not the muscle is functioning normally.

The treatment of choice is percutaneous balloon valvuloplasty and is done when a resting peak gradient is seen to be >60mm Hg or a mean >40mm Hg is observed.

Chest X-ray may also assist in diagnosis, showing left atrial enlargement.

Electrocardiography may show "P mitrale", that is, broad, notched P waves in several or many leads with a prominent late negative component to the P wave in lead V, and may also be seen in mitral regurgitation, and, potentially, any cause of overload of the left atrium. Thus, "P-sinistrocardiale" may be a more appropriate term.

A chest x-ray will be given to determine the size of the heart and the blood vessels supplying blood to the lungs.