Esophageal stents are devices used to maintain or restore the lumen of the esophagus. There are several types of esophageal stents including self-expanding plastic stents (SEPS), self-expanding metal stents (SEMS), and biodegradable stents. SEMS are the most commonly used and come in uncovered, partially covered, and fully covered varieties. Stents are used to treat conditions causing dysphagia such as esophageal cancer, benign strictures, leaks, and fistulas. Complications include pain, bleeding, reflux, perforation, migration, and tissue growth through the stent mesh. Placement of stents near the upper esophagus or gastroesophageal junction

1. Esophageal Stent
Dr. Yash Kumar Achantani
OSR

2. Definition
Stents are devices used to maintain or restore
the lumen of hollow organs, vessels, and ducts.

3. History
• Invented in 1856 by the English dentist
Charles Stent .
• The first (self expanding) "stents" used in
medical practice in 1986 by Ulrich Sigwart in
Lausanne were initially called "Wallstents".
• Julio Palmaz et al. created a balloon
expandable stent that is currently used.

4. • Sir Charters Symonds was the first to successfully
place an oesophageal prosthesis across a
malignant stricture.
• There were many modifications of rigid
oesophageal stents in which various materials
(wood, metal, plastic, latex) and designs were
used.
• The rigid prosthesis (plastic and latex) was
extensively used from the 1970s to the 1990s,
but the complication rates and mortality
associated with insertion-related perforations
remained significant.

5. • In the early 1990s, self-expandable metal
stents (SEMS) were developed for
oesophageal use.

6. Types of Esophageal Stents
1. SEPS (self-expanding plastic stents)
2. SEMS (self-expanding metal stents)
3. Biodegradable stents

7. SEPS
• SEPS (Polyflex; Boston Scientific, Natick, Mass)
has been developed for esophageal strictures.
• This stent has a woven polyester skeleton and
is completely covered with a silicone
membrane.

8. • The silicone prevents tissue in growth through
the mesh.
• Polyester braids on the external surface
anchor the stent to the mucosa to limit
migration.

9. SEMS
• There are three varieties of metal stents:
uncovered, partially covered, and fully
covered.
• The advantage of covered stents is that they
resist tumour ingrowth, but they have a higher
migration rate, especially when fully covered
but have advantage of potentially being
removable.

10. • Partially covered stents are uncovered at their
ends, which allows the stent to embed in the
tissue and helps to prevent migration.
• Uncovered stents are less likely to migrate, but
are subject to tumour ingrowth and resultant
obstruction.
• SEMS consist of woven, knitted, or laser-cut
metal mesh cylinders that exert self-expansive
forces until they reach their maximum fixed
diameter.

11. • SEMS are composed of stainless steel, alloys
such as elgiloy and nitinol, or a combination of
nitinol and silicone.
• Elgiloy, an alloy composed primarily of cobalt,
nickel, and chromium, is corrosion resistant
and capable of generating high radial forces.
• Nitinol, an alloy of nickel and titanium, yields
increased flexibility that is helpful for stenting
sharply angulated regions at the cost of lesser
radial force.

12. • To prevent tumour ingrowth, the interstices
between the metal mesh of oesophageal
SEMSs may be wholly or partially covered by a
plastic membrane or silicone.
• For tumours located near the GE junction
(Oesophageal Z-stent with Dual Anti-reflux
valve; Wilson-Cook Medical, Winston-Salem,
NC) uses an extended polyurethane
membrane 8 cm beyond the metal portion of
the stent to prevent gastroesophageal reflux.

13. Biodegradable stents
• Oesophageal Degradable BD (Ella-CS, Czech
Republic) is made from woven surgical suture
material, polydioxanone.
• It is uncovered and does not have an anti-
reflux valve.
• The stent fully degrades in approximately
three months

14. Photograph shows
Atkinson (A) and
Celestin (B) plastic
stents and
Wilson-Cook (C)
Ultraflex nitinol (D),
Wallstent (E),
Gianturco Z (F), and
Esophacoil (G) metal
stents.

16. From left to right,
Boston Scientific’s
Polyflex
Esophageal Stent,
Ultraflex
Esophageal NG
Stent System,
WallFlex Fully
Covered
Esophageal Stent,
and WallFlex
Partially Covered
Esophageal Stent.

19. Indications
• Dysphagia from oesophageal malignancy.
• Benign oesophageal strictures (peptic,
radiation induced, anastomotic, and caustic).
• Postoperative leaks.
• Iatrogenic perforations.

20. • External compression from extraoesophageal
tumours.
• Tracheoesophageal fistulas.
• Achalasia cardia.
• Bleeding varices.

21. Technique
• Assessment of the length of the stricture and
degree of obstruction is the first step.
• If the stricture is too tight to advance a
standard gastroscope, an ultrathin endoscope
may be used.
• To guide accurate stent deployment, the
proximal and distal ends of the stricture need
to be marked appropriately.

22. • During stent selection, it is important to
choose a stent length that is 4 cm longer than
the stricture being stented.
• This allows for 2 cm of stent on either end of
the stricture to decrease the risk of migration.
• Foreshortening is the property of the stent by
which, on fluoroscopy, the stent constrained
in its catheter will appear longer than the
unconstrained deployed stent length.

23. • Stenting a stricture in the cervical oesophagus
ensure at least a 2-cm distance between the
proximal end of the stent and the upper
oesophageal sphincter.

24. Barium swallow shows a short
stricture in the mid oesophagus.
Biopsy showed squamous cell
carcinoma.

25. A guide wire and catheter
combination has been passed
down through the stricture and a
small amount of contrast injected
at the proximal and distal margins
of the tumour.
Paper clips have been taped to the
patient’s skin to indicate the
stricture length.

26. The stent deployment system has
been passed across the stricture.
Note in this example the markers
on the proximal and distal ends of
the stent and also in the centre of
the stent. The stent should be
placed so that the proximal and
distal ends are 2 cm beyond the
stricture.

27. The stent has been
released.
Note the immediate
expansion of the proximal
and distal ends, while the
central area is still
constrained by the tumor.

28. The delivery system has been
removed. The stent expanded
fully over the next 48 hours
without further dilatation.

29. Esophacoil. Barium
esophagogram (lateral
projection) shows a
normally
placed, normally
functioning Esophacoil.

30. Distal oesophageal covered stent traversing the
GOJ.

31. Distal oesophageal
covered stent
traversing the GOJ.

32. Oesophageal stent is noted in the midpart of the
thoracic oesophagus

33. Complications
Complications associated with oesophageal
stents are generally classified as either early or
delayed.
Early complications- 2-4 weeks
• Chest pain, fever, bleeding, gastroesophageal
reflux disease, globus sensation, perforation,
and stent migration

34. Delayed complications- after 4 weeks
• Tumour ingrowth, stent migration, stent
occlusion, development of oesophageal
fistulae, and recurrence of strictures.

35. Perforation. Barium
esophagogram shows a
Celestin tube placed across
the oesophagogastric
junction. There is
extravasation of barium into
the left pleural space and
mediastinum due to
perforation.

36. Tumour ingrowth.
Barium esophagogram
shows an uncoated
Ultraflex nitinol
stent with an irregular
inner contour due to
tumour growth through
the metallie mesh.

37. Combined overgrowth and
ingrowth through an uncovered
stent.

38. Challenges in Oesophageal Stent
Placement
High-Grade Strictures
• If a stricture is very tight or difficult to traverse
with a standard endoscope.
• One option is to use a dilator(Mercury or
tungsten-weighted bougies, Polyvinyl dilators
& Through-the-scope (TTS) balloon dilators).
• Another method involves using a stent with a
smaller diameter.

39. Upper Oesophageal and Cervical Oesophageal
Strictures
• Traditionally, strictures close to the upper
oesophageal sphincter (UES) have been
considered more difficult to manage.
• However, studies have recently demonstrated the
effectiveness and safety of newer stents for the
palliation of dysphagia and sealing of fistulae in
patients with strictures close to the UES.

40. Distal Oesophageal Strictures,
Gastroesophageal Cancers, and Cardia Cancers
• Distal oesophageal strictures still present a
significant challenge because stent placement
across the gastroesophageal junction can lead
to gastroesophageal reflux disease and
aspiration.
• In an attempt to remedy these problems,
stents with antireflux mechanisms have been
developed (Esophageal Z-Stent with Dua Anti-
Reflux Valve)

41. Management of Benign Oesophageal
Conditions
• The use of self-expandable oesophageal stents
for the management of benign conditions has
grown immensely over the past decade.
• Temporary placement of self-expandable stents is
now used in a variety of benign conditions,
including postoperative anastomotic leaks,
refractory strictures due to peptic ulcers or
radiation, and tracheoesophageal fistulae.

42. • SEPS are increasingly being used for the
treatment of benign oesophageal conditions.
• These stents are thought to have several
advantages over standard SEMS—including
low cost, ease of placement and retrieval, and
limited local tissue reaction—and still provide
symptomatic relief of dysphagia

43. Management of Malignant
Oesophageal Diseases
• Despite advances in the diagnosis, staging,
neoadjuvant care, and perioperative care of
patients with oesophageal cancer, the 5-year
survival rate of these patients remains less than
15%, and chemotherapy has shown limited
survival benefit.
• Therefore, patients with incurable oesophageal
and other nonluminal malignancies of the head
and neck often require palliation for dysphagia
and/or tracheoesophageal fistulae.

44. • Currently, SEMS, along with SEPS, have
become the mainstay of treatment for
malignant oesophageal strictures and fistulae.
• Covered stents are commonly used as they
resist tumour ingrowth because they do not
have an uncovered region that embeds into
tissue they also offer the advantage of being
completely removable.

45. • Use of SEMS for treating cancer closer to the
UES is controversial because of the perceived
increased risk of complications such as
perforation, migration, pain, and patient
intolerance.