What are oesophageal stents?
The oesophagus is a hollow muscular tube which takes food from the mouth down to the stomach. If the oesophagus becomes narrowed or blocked in any way, swallowing and eating can be difficult; this symptom is called dysphagia. One way of overcoming this problem is to insert a mesh tube called a stent across the blockage to help to widen the oesophagus.
Most oesophageal stents are inserted for strictures caused by malignant tumours in the oesophagus. Diagnosis will have been made beforehand by endoscopy, a barium study or CT scan.
A stent may be used either as a definitive treatment, or it may be used to improve the patient’s swallowing whilst other treatments such as surgery or radiotherapy are planned.
Occasionally tears in the oesophagus can develop, either spontaneously, during certain procedures such as endoscopy, or if a tumour from the airway grows into the oesophagus. Stents can then be used to cover the affected area and seal the leak.
Temporary or removable stents are also sometimes used to treat benign strictures in the oesophagus, with the stent being removed after a few weeks or months.
What are the different types of stent?
There are a wide variety of stents available for different clinical situations including biodegradable, metal, covered & removable.
For malignant tumours, fully covered or partially covered metal stents are usually used to prevent the tumour growing through the lumen of the stent and reoccluding. Some stents have unique anti-migration features to stop the stent from being pushed down into the stomach by peristalsis. If the stricture is low in the oesophagus and the stent would enter the stomach, a stent with an optional anti-reflux valve may be considered.
Fully covered, removable metal stents can also be used for treating benign diseases that don’t respond to endoscopic balloon dilation or relapse quickly after dilating. These are called refractory benign strictures. The stent keeps the stricture open for a longer amount of time (up to 3 months) and provides longer term relief than balloon dilation from dysphagia after it is removed. A biodegradable stent can also be used here. The biodegradable stent breaks down and bioabsorbs over 8-12 weeks meaning the patient does not have to revisit the hospital for the stent removing.
In the case of a tear or hole in the oesophagus, a fully covered, wide metal stent can be used as an alternative option to surgery to seal the hole, allowing it to heal. Uncovered stents are rarely used at all in modern times for treating oesophageal diseases.
UK Medical distribute the Ella range of oesophageal stents in the UK. These are namely:
The Danis Stent
Danis Stent is a wide metal stent in a unique delivery system especially developed for tamponading bleeding oesophageal varices in an emergency. Oesophageal varices are abnormal, enlarged veins in the tube that connects the throat and stomach.
Usual management of bleeding oesophaeal varices is a Sengstaken-Blakemore tube inserted through the nose or mouth which is inflated in the oesophagus to compress the vessels and seal the bleed. It can only stay in situ for up to 72 hours and the patient can’t eat or drink whilst it’s in place; the patient also has to be intubated to ensure they can still breath which means they need to be managed in ITU.
Danis stent compresses the vessels & seals the bleed whilst still allowing the patient to eat & drink. They don’t need to be intubated and can be managed on the ward as opposed to ITU making the care pathway more economic with better patient outcomes. It can also be left in situ for up to 7 days allowing clinicians more time to plan future treatment options.
The Danis Seal
The Danis Seal is a wide metal stent indicated as a treatment option for oesophageal and gastric leakage from anastomotic wound dehiscence, oesophageal ruptures and perforations. The silicone covered nitinol stent has features to reduce migration in a non-strictured oesophagus.
Traditionally, oesophageal perforations have been managed by surgery, but stenting may result in better clinical outcomes as described in Kaman et al 2010:
‘Placements of removable covered SEMs have been described in the care of patients with oesophageal perforations with excellent results. By using removable SEMs, both primary and secondary oesophageal leaks are being treated with reduced hospital stay, fewer adjunctive procedures and early resumption of oral diet’.
BD Biodegradable Stent
The Ella Biodegradable (BD) stent is a unique, patented stent intended to facilitate long-term remodelling of refractory benign oesophageal diseases, including petptic, caustic and anastomotic strictures. It hydrolytically biodegrades in the oesophagus between 8-12 weeks.
Designed to minimise the need for re-interventions and streamline the patient pathway, the BD stent provides a cost effective, patient-focussed alternative to repeat high-frequency oesophageal dilatation. The BD stent doesn’t need to be removed like some stents do, but simply biodegrades, helping to improve patient quality of life.
As outlined in the BSG guidelines, ‘BD stent should be ‘considered to reduce the frequency of dilatation in selected cases. In the largest study to date, sequential placement of a first, second and then third biodegradable stent resulted in a median dysphagia free period of 90, 55 and 106 days, respectively.’
HV+ Oesophageal Stent
The Ella HV+ fully removable oesophageal stent is specifically designed with a unique flexible collar to reduce migration and tissue in-growth. It has a braided design which has high radial force to withstand traversing tight strictures.
Indicated for both malignant and benign strictures, HV+ helps to minimise re-interventions providing clinician and patient pathway benefits.
The HV+ stent has been shown to have one of the best migration rates of all metal stents on the market at 4.7% (ROST 2) as well as being exceptionally robust and resistant to stent fracture. Testing shows no change to the integrity of the stent after 3 months saturated in a chemical solution with a pH comparable to gastric acid.
Diseases of the oesophagus
There are several diseases that can result in a oesophageal stents being used, these include GORD, achalasia, oesophageal perforations, varices, malformations and cancer. Read more about diseases of the oesophagus here.