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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.
Laryngotracheal stenosis refers to abnormal narrowing of the central air passageways. This can occur at the level of the larynx, trachea, carina or main bronchi.
In a small number of patients narrowing may be present in more than one anatomical location.
In the first stage of restenosis, administering anti-platelet drugs (called IIb/IIIa inhibitors) immediately after surgery greatly reduces the chance of a thrombosis occurring.
Drug-eluting stents are now being trialled in Europe, Canada and the USA, as well as in Asia-Pacific. These stents are coated with pharmaceuticals that inhibit tissue growth and thus reduce the risk of restenosis from scar-tissue and cell proliferation.
There has been some success with these new stents in reducing the occurrence of restenosis, with clinical studies showing an incidence rate of 5% or lower.
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.
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 adults and children found to have coarctation, treatment is conservative if asymptomatic, but may require surgical resection of the narrow segment if there is arterial hypertension. The first operations to treat coarctation were carried out by Clarence Crafoord in Sweden in 1944. In some cases angioplasty can be performed to dilate the narrowed artery, with or without the placement of a stent graft.
For fetuses at high risk for developing coarctation, a novel experimental treatment approach is being investigated, wherein the mother inhales 45% oxygen three times a day (3 x 3–4 hours) beyond 34 weeks of gestation. The oxygen is transferred via the placenta to the fetus and results in dilatation of the fetal lung vessels. As a consequence, the flow of blood through the fetal circulatory system increases, including that through the underdeveloped arch. In suitable fetuses, marked increases in aortic arch dimensions have been observed over treatment periods of about two to three weeks.
The long term outcome is very good. Some patients may, however, develop narrowing (stenosis) or dilatation at the previous coarctation site. All patients with unrepaired or repaired aortic coarctation require follow up in specialized Congenital Heart Disease centers.
If restenosis occurs without a stent, it is usually treated with more angioplasty. Once restenosis has occurred and been treated by angioplasty, the chances of restenosis occurring again are increased by a factor of 2. This treatment is also used if restenosis occurs at either the proximal or distal end of the stent.
If restenosis occurs within a stent (also known as in-stent stenosis), it may be treated with repeated angioplasty and insertion of another stent inside the original, sometimes with a drug-eluting stent.
Over the past 5 years, ISR is preferentially treated with a drug eluting balloon, which is a balloon coated with the same anticancer drugs that prevent restenosis. The Balloon avoids the need for a double layer of metal which is used when an in-stent restenosis is treated with another stent within the original stent
Alternative treatments include brachytherapy, or intracoronary radiation. The radiation kills cells and inhibits tissue growth (similar to a patient undergoing cancer therapy).
The epidemiology of pulmonary valve stenosis can be summed up by the congenital aspect which is the majority of cases, in broad terms PVS is rare in the general population.
Surgical treatment involves resection of the stenosed segment and re-anastomsis. Two complications specific to this surgery are Left recurrent nerve palsy and chylothorax, as the recurrent laryngeal nerve and thoracic duct are in the vicinity. Chylothorax is a troublesome complication and is usually managed conservatively by adjusting the diet to eliminate long chain fatty acids and supplementing medium chain triglycerides. When conservative management fails surgical intervention is required. Fluorescein dye can aid in the localisation of chyle leak.
A stenosis is an abnormal narrowing in a blood vessel or other tubular organ or structure. It is also sometimes called a stricture (as in urethral stricture).
Stricture as a term is usually used when narrowing is caused by contraction of smooth muscle (e.g., achalasia, prinzmetal angina); stenosis is usually used when narrowing is caused by lesion that reduces the space of lumen (e.g., atherosclerosis). The term coarctation is another synonym, but is commonly used only in the context of aortic coarctation.
Restenosis is the recurrence of stenosis after a procedure. The term is from Ancient Greek στενός, "narrow".
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.
Tricuspid valve stenosis itself usually doesn't require treatment. If stenosis is mild, monitoring the condition closely suffices. However, severe stenosis, or damage to other valves in the heart, may require surgical repair or replacement.
The treatment is usually by surgery (tricuspid valve replacement) or percutaneous balloon valvuloplasty. The resultant tricuspid regurgitation from percutaneous treatment is better tolerated than the insufficiency occurring during mitral valvuloplasty.
Stenosis of the pulmonary artery is a condition where the pulmonary artery is subject to an abnormal constriction (or stenosis). Peripheral pulmonary artery stenosis may occur as an isolated event or in association with Alagille syndrome, Berardinelli-Seip congenital lipodystrophy type 1, Costello syndrome, Keutel syndrome, nasodigitoacoustic syndrome (Keipert syndrome), Noonan syndrome or Williams syndrome.
It should not be confused with a pulmonary valve stenosis, which is in the heart, but can have similar hemodynamic effects. Both stenosis of the pulmonary artery and pulmonary valve stenosis are causes of pulmonic stenosis.
In some cases it is treated with surgery.
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
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.
Potential non-surgical treatments include:
- Education about the course of the condition and how to relieve symptoms
- Medicines to relieve pain and inflammation, such as acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs)
- Exercise, to maintain or achieve overall good health, aerobic exercise, such as riding a stationary bicycle, which allows for a forward lean, walking, or swimming can relieve symptoms
- Weight loss, to relieve symptoms and slow progression of the stenosis
- Physical therapy, to provide education, instruction, and support for self-care; physical therapy instructs on stretching and strength exercises that may lead to a decrease in pain and other symptoms
For infants and children, balloon valvuloplasty, where a balloon is inflated to stretch the valve and allow greater flow, may also be effective. In adults, however, it is generally ineffective, as the valve tends to return to a stenosed state. The surgeon will make a small incision at the top of the person's leg and proceed to insert the balloon into the artery. The balloon is then advanced up to the valve and is inflated to stretch the valve open.
The general purpose of the following treatment methods is to divert the flow of CSF from the blocked aqueduct, which is causing the buildup of CSF, and allow the flow to continue. Another goal of these treatments is to reduce the stress within the ventricles. Studies have not shown that either of the following treatments results in a higher IQ of the patient, and there is not statistical difference in a patient's quality of life based on treatment method. The following treatment methods are not used for aqueductal stenosis caused by tumor compression; if the obstruction is a direct result of tumor compression, CSF flow may be normalized by the surgical removal of the tumor.
An extracranial shunt is essentially a sturdy tube with a catheter on one end to drain the third ventricle. The shunt also has a valve which serves to maintain one-way flow of the CSF and regulates the flow rate. The end with the catheter is placed in the third ventricle to drain the excess CSF and the other end is placed in the peritoneal cavity or atrium of the heart (making it a ventriculoperitoneal or ventriculoatrial shunt, respectively). The excess CSF which is diverted to a cavity is then reabsorbed by the surrounding tissue where it is drained to.
The procedure to insert this device is a technically straightforward endoscopic surgery with a low mortality rate (essentially 0% mortality since the 1970s). If the shunt has an adjustable valve the current method of setting the valve pressure is to choose one setting, observe the patient to see if CSF flow improves and the symptoms lessen over time, and adjust the pressure setting as needed if improvement isn't seen. For example, if there is not enough CSF flow, another surgery is performed to lower the valve pressure so that less force needs to be applied to open the valve and thereby drain more CSF.
This treatment method has several possible problems with it (with a 50% failure rate in 2 years), and unfortunately shunt malfunctions and associated complications cause a death rate of 1.2% per year. Problems which can necessitate a secondary surgery to fix them include: mechanical failure, incorrect catheter size, inappropriate valve drainage pressure, and infection.
- Inappropriate valve pressure can lead to "overdraining" or "underdraining", both of which should be treated by adjusting the valve pressure. Overdraining occurs when the valve pressure is too low and CSF flows out of the third ventricle too quickly. The ventricle then collapses and blood vessles can be torn in the process. This in turn can lead to headache, hemorrhage, or slit ventricle syndrome. Underdraining occurs when the valve pressure is too high and CSF flows out too slowly. This results in symptoms of hydrocephalus as the CSF is still collecting rather than being absorbed or diverted.
- Risk of infection is due to the fact that a foreign object is being introduced into the body. Infection can have symptoms of fever and soreness of the neck and shoulders.
Potential surgical treatments include:
- Anterior cervical discectomy and fusion - A surgical treatment of nerve root or spinal cord compression by decompressing the spinal cord and nerve roots of the cervical spine with a discectomy in order to stabilize the corresponding vertebrae.
- Laminoplasty - A surgical procedure relieve pressure on the spinal cord by cutting the lamina on both sides of the affected vertebrae (cutting through on one side and merely cutting a groove on the other) and then "swinging" the freed flap of bone open.
- Laminectomy - A surgical procedure in which the lamina of the vertebra is removed or trimmed to widen the spinal canal and create more space for the spinal nerves and thecal sac.
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 Norwood procedure is a procedure to correct fetal aortic stenosis that occurs after birth. This typically consists of three surgeries creating and removing shunts. The atrial septum is removed, the aortic arch is reconstructed to remove any hypoplasia, and then the main pulmonary artery is connected into this reconstructed arch, resulting in the right ventricle ejecting directly into systemic circulation. In the end, the right ventricle is pumping blood to systemic circulation and to the lungs. However, this procedure carries a very high risk of failure and the patient will likely require a heart transplant.
Another treatment option is to correct the stenosis in utero. In this procedure, fetal positioning is crucial. It is important that the left chest is located anteriorly, and that there are no limbs between the uterine wall and the apex of the left ventricle. The LV apex needs to be within 9 cm of the abdominal wall and the left ventricle outflow track has to be parallel to the intended cannula course in order for the wire to be blindly directed at the aortic valve. A 11.5 cm long, 19-gauge cannula and stylet needle passes through the mother’s abdomen, uterine wall, and fetal chest wall into the left ventricle of the fetus. Then a 0.014 inch guide wire is passed across the stenosis aortic valve, where a balloon is inflated to stretch the aortic annulus.
An alternative to the Norwood procedure is known as the hybrid procedure, was developed in 2008. In the hybrid procedure, bilateral pulmonary artery bands are positioned to limit pulmonary flow while, at the same time, placing a stent in the ductus arteriosus to hold it open. This maintains the connection between the aorta and the systemic circulation. A balloon atrial septostomy is also done. This ensures that there is enough of a connection between the two atria of the heart to provide open blood flow and mixing of oxygen rich and poor blood This procedure spares the baby from undergoing open heart surgery until they are older. They typically come back at 4–6 months of age when they are stronger for the open heart surgery.
The definitive treatment of pyloric stenosis is with surgical pyloromyotomy known as Ramstedt's procedure (dividing the muscle of the pylorus to open up the gastric outlet). This surgery can be done through a single incision (usually 3–4 cm long) or laparoscopically (through several tiny incisions), depending on the surgeon's experience and preference.
Today, the laparoscopic technique has largely supplanted the traditional open repairs which involved either a tiny circular incision around the navel or the Ramstedt procedure. Compared to the older open techniques, the complication rate is equivalent, except for a markedly lower risk of wound infection. This is now considered the standard of care at the majority of children's hospitals across the US, although some surgeons still perform the open technique. Following repair, the small 3mm incisions are hard to see.
The vertical incision, pictured and listed above, is no longer usually required, though many incisions have been horizontal in the past years.
Once the stomach can empty into the duodenum, feeding can begin again. Some vomiting may be expected during the first days after surgery as the gastrointestinal tract settles. Rarely, the myotomy procedure performed is incomplete and projectile vomiting continues, requiring repeat surgery. Pyloric stenosis generally has no long term side-effects or impact on the child's future.
Penile Revascularization is a specialized vascular-surgical treatment option for Erectile Dysfunction. The 2009 International Consultation on Sexual Dysfunctions recommended that revascularization be limited to nonsmoker, nondiabetic men younger than 55 years of age with isolated stenosis of the internal pudendal artery with absence of venous leak.
Patients with persistent erectile dysfunction after revascularization may benefit from repeat penile duplex ultrasound and pelvic angiography to evalauate the status of the bypass graft and to exclude the presence of a PASS as the cause. The prevalence of an aberrant obturator artery arising from the inferior epigastric artery is approximately 10.5%. If an aberrant obturator artery is visualized arising from the inferior epigastric artery prior to surgical penile revascularization, consideration should be given toward using an alternative source artery or to embolization to avoid the creation of a Penile Artery Shunt Syndrome encountered in this described case.
Congenital stenosis of vena cava is a congenital anomaly in which the superior vena cava or inferior vena cava has an aberrant interruption or coarctation.
In some cases, it can be asymptomatic, and in other cases it can lead to fluid accumulation and cardiopulmonary collapse.