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Surgical correction is indicated in all double aortic arch patients with obstructive symptoms (stridor, wheezing, pulmonary infections, poor feeding with choking). If symptoms are absent a conservative approach (watchful waiting) can be reasonable. Children with very mild symptoms may outgrow their symptoms but need regular follow-up.
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.
The procedure is performed in general anesthesia. It is useful to place pulse oximeter probes on "both hands" and "one foot" so that test occlusion of one arch or its branches will allow confirmation of the anatomy. In addition blood pressure cuffs should also be placed on one leg and both arms to confirm the absence of a pressure gradient when the intended point of division of the lesser arch is temporarily occluded with forceps.
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.
Treatment of a laryngeal cleft depends on the length and resulting severity of symptoms. A shallow cleft (Type I) may not require surgical intervention. Symptoms may be able to be managed by thickening the infant's feeds. If symptomatic, Type I clefts can be sutured closed or injected with filler as a temporary fix to determine if obliterating the cleft is beneficial and whether or not a more formal closure is required at a later date. Slightly longer clefts (Type II and short Type III) can be repaired endoscopically. Short type IV clefts extending to within 5 mm below the innominate artery can be repaired through the neck by splitting the trachea vertically in the midline and suturing the back layers of the esophagus and trachea closed. A long, tapered piece of rib graft can be placed between the esophageal and tracheal layers to make them rigid so the patient will not require a tracheotomy after the surgery and to decrease chances of fistula postoperatively. Long Type IV clefts extending further than 5 mm below the innominate artery cannot be reached with a vertical incision in the trachea, and therefore are best repaired through cricotracheal resection. This involves separating the trachea from the cricoid cartilage, leaving the patient intubated through the trachea, suturing each of the esophagus and the back wall of the trachea closed independently, and then reattaching the trachea to the cricoid cartilage. This prevents the need for pulmonary bypass or extracorporeal membrane oxygenation.
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.
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.
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.
A method for repairing long-gap esophageal atresia using magnets has been developed, that does not require replacing the missing section with grafts of the intestine or other body parts. Using electromagnetic force to attract the upper and lower ends of the esophagus together was first tried in the 1970s by using steel pellets attracted to each other by applying external electromagnets to the patient. In the 2000s a further refinement was developed by Mario Zaritzky's group and others. The newer method uses permanent magnets and a balloon.
1. The magnets are inserted into the upper pouch via the baby's mouth or nose, and the lower via the gastrotomy feeding tube hole (which would have had to be made anyway to feed the baby, therefore not requiring any additional surgery).
2. The distance between the magnets is controlled by a balloon in the upper pouch, between the end of the pouch and the magnet. This also controls the force between the magnets so it is not strong enough to cause damage.
3. After the ends of the esophagus have stretched enough to touch, the upper magnet is replaced by one without a balloon and the stronger magnetic attraction causes the ends to fuse (anastomosis).
In April 2015 Annalise Dapo became the first patient in the United States to have their esophageal atresia corrected using magnets.
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.
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.
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.
The condition was initially thought untreatable until surgeon Alfred Blalock, cardiologist Helen B. Taussig, and lab assistant Vivien Thomas at Johns Hopkins University developed a palliative surgical procedure, which involved forming a side to end anastomosis between the subclavian artery and the pulmonary artery. This first surgery was depicted in the film "Something the Lord Made". It was actually Helen Taussig who convinced Alfred Blalock that the shunt was going to work. This redirected a large portion of the partially oxygenated blood leaving the heart for the body into the lungs, increasing flow through the pulmonary circuit, and greatly relieving symptoms in patients. The first Blalock-Thomas-Taussig shunt surgery was performed on 15-month-old Eileen Saxon on November 29, 1944 with dramatic results.
The Potts shunt and the Waterston-Cooley shunt are other shunt procedures which were developed for the same purpose. These are no longer used.
Currently, Blalock-Thomas-Taussig shunts are not normally performed on infants with TOF except for severe variants such as TOF with pulmonary atresia (pseudotruncus arteriosus).
Tet spells may be treated with beta-blockers such as propranolol, but acute episodes require rapid intervention with morphine or intranasal fentanyl to reduce ventilatory drive, a vasopressor such as phenylephrine, or norepinephrine to increase systemic vascular resistance, and IV fluids for volume expansion.
Oxygen (100%) may be effective in treating spells because it is a potent pulmonary vasodilator and systemic vasoconstrictor. This allows more blood flow to the lungs by decreasing shunting of deoxygenated blood from the right to left ventricle through the VSD. There are also simple procedures such as squatting and the knee chest position which increase systemic vascular resistance and decrease right-to-left shunting of deoxygenated blood into the systemic circulation.
Treatments for the condition vary depending on its severity. The most immediate and effective treatment in the majority of cases is a surgical repair to close the fistula/s and reconnect the two ends of the esophagus to each other. Although this is usually done through an incision between the ribs on right side of the baby, a technique using three small incisions (thoracoscopy) is being used at some centers. In a minority of cases, the gap between upper and lower esophageal segments may be too long to bridge. In some of these so-called long gap cases, though, an advanced surgical treatment developed by John Foker, MD, may be utilized to elongate and then join together the short esophageal segments. Using the Foker technique, surgeons place traction sutures in the tiny esophageal ends and increase the tension on these sutures daily until the ends are close enough to be sewn together. The result is a normally functioning esophagus, virtually indistinguishable from one congenitally well formed. Unfortunately, the results have been somewhat difficult to replicate by other surgeons and the need for multiple operations has tempered enthusiasm for this approach.
The optimal treatment in cases of long gap esophageal atresia remains controversial. Traditional surgical approaches include gastrostomy followed by gastric pull-up, colonic transposition and jejunum transposition. Gastric pull-up has been the preferred approach at many specialized centers, including Great Ormond Street (London) and Mott Children's Hospital (Ann Arbor). Gastrostomy, or G-tube, allows for tube feedings into the stomach through the abdominal wall. Often a cervical esophagostomy will also be done, to allow the saliva which is swallowed to drain out a hole in the neck. Months or years later, the esophagus may be repaired, sometimes by using a segment of bowel brought up into the chest, interposing between the upper and lower segments of esophagus.
Post operative complications sometimes arise, including a leak at the site of closure of the esophagus. Sometimes a stricture, or tight spot, will develop in the esophagus, making it difficult to swallow. This can usually be dilated using medical instruments. In later life, most children with this disorder will have some trouble with either swallowing or heartburn or both. Esophageal dismotility occurs in 75-100% of patients.
Tracheomalacia—a softening of the trachea, usually above the carina (carina of trachea), but sometimes extensive in the lower bronchial tree as well—is another possible serious complication. Even after esophageal repair (anastomosis) the relative flaccidity of former proximal pouch (blind pouch, above) along with esophageal dysmotility can cause fluid buildup during feeding. Owing to proximity, pouch ballooning can cause tracheal occlusion. Severe hypoxia ("dying spells") follows and medical intervention can often be required.
A variety of treatments for tracheomalacia associated with esophageal atresia are available. If not severe, the condition can be managed expectantly since the trachea will usually stiffen as the infant matures into the first year of life. When only the trachea above the carina is compromised, one of the "simplest" interventions is aortopexy wherein the aortic loop is attached to the rear of the sternum, thereby mechanically relieving pressure from the softened trachea. An even simpler intervention is stenting. However, epithelial cell proliferation and potential incorporation of the stent into the trachea can make subsequent removal dangerous.
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.
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.
A laryngeal cleft or laryngotracheoesophageal cleft is a rare congenital abnormality in the posterior laryngo-tracheal wall. It occurs in approximately 1 in 10,000 to 20,000 births. It means there is a communication between the oesophagus and the trachea, which allows food or fluid to pass into the airway.
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.
To prevent an TIF, intubation time should be limited to less than 2 weeks and proper techniques should be used when performing tracheotomies. The occurrence of an TIF can be reduced by using more flexible and blunt tracheostomy tubes and insuring that the tubes are properly aligned in the patients. Placing the tracheostomy between the second and third tracheal rings can minimize the risk of an TIF. Repetitive head movements, especially, hyperextension of the neck should be avoided as since this movement results in contact between the innominate artery and the underside of the tube.
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 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 formation of a TIF is a medical emergency and requires immediate intervention. Blood volume control, management of the hemorrhage, and adequate oxygenation should be insured in these patients. In a majority of TIF cases (85%), hyperinflation of the tracheostomy cuff will control the bleeding, while the patient is prepared for surgery. However, if this fails the tracheostomy cuff must be removed, and the patient must be intubated from above. Next, pressure from the index finger can be applied on the bleeding site from within the tracheostomy to control the bleeding. In addition, the "Utley Maneuver", which involves digital compression of the artery against the posterior wall of the manubrium of the sternum following a right infraclavicular incision, may be used to urgently control the bleeding When the bleeding is controlled the patient should be immediately transferred on the operating room.
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.