Ask the expert

Ask the
expert
Endoscopic management of benign esophageal
strictures, rings and webs
1. Q: I have heard several variations on the traditional “rule of 3.” What is the correct rule? Because there is no tactile
sensation when using balloon dilation, can the “rule of 3” (or another rule) be used to guide the endoscopist?
Ask the expert features
A: In my view, the “rule of 3” means that no more than three dilators of successively increasing diameter should
be passed through a stricture in a single session (corresponding to a total increase in diameter of 3 x 1 = 3 mm).
questions submitted by
Although this ‘‘rule’’ is easily applicable as a clinical guideline, no studies have demonstrated that it improves safety
members, with answers
or efficacy. Therefore, one could argue that in very tight or long strictures, only one or two dilators should be passed
provided by ASGE physician
in each dilation session. It is generally advised to limit initial dilation to 39 to 45F (corresponding to a diameter of
13 to 15 mm).
experts. ASGE’s Publication
Committee identifies
In my practice, I always start the first dilation session in a patient using the “rule of 3;” however, depending on the
tightness of the stricture and whether the stricture has completely recurred after the first dilation session, I use a 4 x
1 mm or even a 3 x 2 mm increase in diameter in subsequent dilation sessions.
authors and topics for
the column. In this issue,
Peter D. Siersema, MD,
PhD, FASGE, responds
2. Q: What is your approach to treating a refractory, benign esophageal stricture? Does your approach depend
on the presumed etiology and location of the stricture?
A: I follow the treatment algorithm described in a recently published Technical Review in GIE: Gastrointestinal
Endoscopy.1 This review describes the various modalities that are available for refractory benign esophageal
strictures, depending on the number of procedures performed and the presumed etiology and location of
the stricture.
to questions on the
endoscopic management
of benign esophageal
strictures, rings and webs.
In short, the first step is balloon or Savary dilation, preferably to a maximum diameter of 16 to 18 mm. It
is recommended that at least five dilation sessions be performed to the maximum diameter. The next step
is to combine dilation with intralesional corticosteroid injections followed by dilation. I suggest limiting
intralesional corticosteroid injection plus dilation to a maximum of three sessions.
In refractory Schatzki rings and anastomotic strictures, refractory strictures can be treated with incisional
therapy using needle-knife electrocautery, an insulation-tipped (IT) knife or argon plasma coagulation (APC).
Again, I suggest performing a maximum of three treatment sessions mainly due to a lack of further effect after
more than three sessions.
Stent placement is a treatment option used in selective cases when the stricture recurs within a short time
interval. When stent placement is successful but the stricture persists after stent removal, stenting for a
longer time can be considered because it is likely that the inflammatory reaction underlying the stricture will
ultimately subside and the desired luminal diameter achieved at that time will remain.
Dr. Siersema is a professor
of Gastroenterology and
head of the Department
of Gastroenterology and
Hepatology at the Utrecht
Medical Center, Utrecht,
The Netherlands.
Disclosures: Astra Zeneca
BV, Boston Scientific Corp.,
Cook Medical Ltd., Janssen
BV and Philips BV.
Peter D. Siersema, MD,
PhD, FASGE
An alternative treatment option is to instruct the patient on self-bougienage using Maloney dilators. In my
experience, self-bougienage is most successful when there is favorable anatomy (e.g., a proximal stricture of
caustic or anastomotic origin without significant diverticula formation). There is a subgroup of patients in
whom all efforts to dilate a refractory benign esophageal stricture are not successful and a surgical procedure
is indicated.
3. Q: What is the evidence to support the clinical practice of empiric dilation of the esophagus in patients
without a mechanical stricture, ring or web but with symptoms of dysphagia?
A: Schatzki rings and esophageal webs may give rise to symptoms of dysphagia but may be easily passed with a normal
diameter endoscope. The ring or web may not be recognized by the endoscopist. In many patients, symptoms from
rings or webs occur episodically, for example, when the patient is under stressful circumstances. It is my personal
experience that dilation up to 18 to 20 mm is effective and will eliminate dysphagia in most patients with rings or
webs for a sustained period of time. Characteristically, resistance during dilation is only slight, if present at all. The
pathogenesis of dysphagia due to rings or webs is unclear. Apart from a mechanical factor, dysmotility may play a
role. A psychological component also cannot be excluded, and the recognition of one or more provocative factors
by patients may reduce or even eliminate symptoms.
continued on page 2
ASGE News March | April 2011 1
Ask the expert continued from page 1
4. Q: When would you consider using local corticosteroid injections for management of strictures? How strong is
the published evidence to support this method? Please describe what is the best technique or method (i.e.,
type of steroid, dose, location, frequency, etc.).
A: Dilation combined with intralesional corticosteroid injection should be considered whenever at least five
dilations of a benign esophageal stricture have not been successful. Until now, studies on the combined
use of intralesional corticosteroids with dilation have been reported to be effective in a variety of
strictures, particularly peptic strictures. The mechanism of action is suggested to be the local inhibition
of the inflammatory response. I typically use injections of 0.5 mL triamcinoloneacetonide (40 mg/mL),
administered into each of the four quadrants of the stricture, for a total dose of 80 mg, followed by
dilation in the same endoscopy session.
5. Q: What is the best way to dilate a stricture? Are there any head-to-head trials comparing Maloney, Savary
and balloon dilation? Please discuss the pros and cons of each method and in which situations one
method is preferred over the others.
A: There are no randomized trials comparing Maloney, Savary and balloon dilators. One study retrospectively
compared Maloney, balloon-type (both the hydrostatic and pneumatic type) and Savary dilators in 102,
156 and 90 sessions, respectively. An increased perforation rate was found with Maloney dilators that were
passed blindly into complex strictures.2 Therefore, if Maloney dilators are used, it is advisable to use them
only in patients with simple strictures.
Both Savary and balloon dilators are currently the most frequently used dilators by far. No clear advantage
of either balloon or Savary dilation has been demonstrated.3,4 I prefer Savary dilators in the majority of
strictures because they allow me to feel the degree of resistance of the stricture while advancing dilators
of increasing diameters. In addition, Savary dilators are more cost effective because they are reusable,
compared with balloon dilators that are intended for single use only. Lastly, the fixed diameter of a Savary
dilating catheter is consistently achieved, whereas the “waist” of a balloon dilator may or may not be
eliminated and may only be affirmed with radiographic guidance.
6. Q: I have heard that some endoscopists use “removable” plastic or metal stents to treat refractory esophageal
and/or anastomotic strictures.
a) When would you use esophageal stenting for benign disease? What types of stents are truly removable? Which stents are FDA-approved for endoscopic removal? What technique would you use to remove them? I have heard that some stents can be quite difficult to remove and, moreover, can fracture in the process of being removed, which makes me concerned about placing them.
b) How do you select the stent diameter? How do you select the stent length? Are there any differences between the safety and effectiveness of partially covered and fully covered esophageal stents for refractory, benign strictures? How does the endoscopist choose between proximal and distal stent
release mechanisms for benign strictures?
A: In the past few years, temporary stent placement has increasingly been used for treating refractory benign
esophageal strictures. Stents are used to permit dilation for a prolonged period of time and to reduce the risk
of recurrent stricture formation.
Stent types that have been used for benign esophageal strictures include partially covered and fully covered
metal stents and fully covered plastic stents (Polyflex stents). Of these, only Polyflex stents are FDA-approved
for treating benign esophageal strictures. Clinical success, defined as dilation-free remission, can be achieved in
more than 50 percent of patients.5 The success rate is lower in patients with a more proximal localization of the
stricture; however, as expected with fully covered Polyflex stents, a relatively high early migration rate
(<4 weeks) (24 percent) is observed.
Overall, the main limitation of partially covered metal stents, and to a lesser degree fully covered metal stents,
is the occurrence of tissue ingrowth and overgrowth, causing recurrent dysphagia and precluding easy stent
removal.1 Moreover, anecdotal reports have reported stent fracturing with the fully covered Alimaxx-E stent
(Merit Medical, South Jordan, Utah) when it is removed after some weeks. I have a preference for using Polyflex
stents or fully covered metal stents for refractory benign esophageal strictures.
continued on page 3
ASGE News March | April 2011 2
Ask the expert continued from page 2
The stent diameter depends on the diameter of the stricture following the rule that strictures tighter
than 7 to 8 mm are treated with stents of normal diameter (18 to 20 mm), while wider strictures or
those with pre-stenotic dilatation are treated with stents of larger diameter (25-28 mm). The stent length
is determined by my preference to extend the proximal end of the stent at least 5 cm proximal to the
stricture and to extend the distal end not too distally in the stomach. I use a distal release mechanism for
stent placement because it allows maximum control while placing the stent. Stent removal can be easily
performed by grasping the upper or lower end of the stent or the attached lasso with a grasping forceps.
7. Q: Does fluoroscopy always have to be used when performing over-the-wire dilation using Savary dilators?
Has use of fluoroscopy been proven to reduce the risk of complications of Savary dilation?
A: The efficacy and safety of endoscopic dilation without fluoroscopy has been shown in several studies.6
Although not proven, I recommend fluoroscopic guidance to enhance safety during dilation, especially for
more difficult strictures that cannot be passed endoscopically, strictures that are longer in length and strictures
that are angulated or multiple.
8. Q: When would you recommend pneumatic balloon dilation as primary treatment for achalasia? Please
describe the best method for performing pneumatic balloon dilation.
A: There is little doubt in the literature that pneumatic dilation is the first-line nonsurgical treatment for achalasia.
There is, however, no consensus on the optimal method of performing pneumatic dilation for achalasia.
My preferred method is to start with a 30-mm diameter balloon. The procedure is performed under conscious
sedation, sometimes under propofol sedation. I place a guidewire into the duodenum under endoscopic
guidance and then remove the endoscope. The next step is to pass a balloon dilator over the guidewire into
the stomach.
I fill the balloon with contrast that is diluted 1:1 with water. The endoscope is then reinserted in the
esophagus to visualize the withdrawal of the deflated balloon to the esophagus, until the mark on the mid-part
of the balloon reaches the stricture. I use fluoroscopy to confirm the position of the balloon.
The balloon is inflated according to the instructions of the manufacturer. When fully inflated, an ischemic ring
can be seen at the site of the stricture through the transparent balloon. I usually keep the balloon inflated until
the impression of the ring on the balloon disappears or up to a maximum of three minutes.
In our unit, we perform a series of three dilations with two days in between. In the follow-up sessions, we
use a balloon of the same size or a larger size, depending on the previous dilation result and the esophageal
diameter until a maximum balloon diameter of 35 to 40 mm is achieved. After the dilation, I carefully inspect
the dilation site for any sign of perforation.
During and after the procedure, the patient is observed for chest pain and vital signs are monitored closely.
Chest x-ray or computed tomography is carried out if the severity of the chest pain raises the possibility
of esophageal rupture. It has been shown that the method of positioning the endoscope above the balloon
without fluoroscopy gives results similar to those with fluoroscopy alone.7
9. Q: When would you use endoscopic injection of botulinum toxin as treatment for achalasia? What are the
indications and contraindications? Is it true that injecting botulinum toxin can make subsequent surgery
technically more difficult?
A: It has been shown that the best results with botulinum toxin can be achieved in patients with vigorous
achalasia, older persons and patients whose lower esophageal sphincter pressures do not exceed ≥50 percent
of the upper limit of normal.8 However, the use of botulinum toxin is limited by its lack of long-term efficacy,
with recurrence rates of approximately 50 percent after one year and universal symptomatic relapse at two
years.9 In our unit, the main candidates for botulinum toxin are old and frail patients who are unfit for
pneumatic dilation or Heller myotomy. In addition, botulinum toxin injections can be considered in patients
who are symptomatic but do not show all of the characteristic manometric abnormalities of achalasia. In my
experience, the prior injection of botulinum toxin has no effect on the result of subsequent surgery.
continued on page 4
ASGE News March | April 2011 3
Ask the expert continued from page 3
10. Q: What is the best method for dilating the following esophageal strictures: Caustic, peptic, anastomotic,
radiation-induced and variceal sclerotherapy-induced?
A: In general, all of these strictures can well be managed by dilation with Savary or balloon dilators. If refractory or
recurrent, one should follow the treatment algorithm proposed in a recently published Technical Review in GIE.1
In radiation-induced strictures, especially those in the cervical or proximal esophagus, it can be difficult to advance
a guidewire through the stricture, due to the inability to identify the true lumen of a stenotic segment. To
prevent a ”false route” of the guidewire, the combined antegrade and retrograde dilation (CARD) technique
can then be used. This endoscopic ”rendezvous” approach enables better control during dilation.
The rendezvous approach is accomplished by passing a small-diameter endoscope retrogradely into the
patient’s esophagus through the gastric lumen, using a mature gastrostomy or jejunostomy tract for access.
Subsequently, a guidewire is passed under fluoroscopic guidance from the stomach across the stricture. If
the lumen is not detected from the distal side, a guidewire puncture or creation of a small access hole in
the stricture with a pre-cut knife under fluoroscopic guidance, followed by passage of a guidewire can be
considered. The guidewire is detected antegradely and picked-up with a proximally positioned endoscope.
Dilation can then be performed. It is a relatively effective and safe procedure in experienced hands.
Finally, as a general rule, I apply the “rule of 3” in strictures resulting from the endoscopic treatment of
esophageal varices. These strictures used to be common with the use of sclerotherapy; however, since band
ligation has largely replaced sclerotherapy for the treatment of esophageal varices, this complication is
now rare.
In some circumstances, ineffective acid suppression may promote stricture recurrence. In these settings, it is
important to ensure that patients are on effective acid-suppression therapy.
11. Q: It seems that although controlled radial expansion (CRE) balloons are easier to use, bougies give
longer-lasting results. Is this true?
A: I think that using CRE balloons or bougies in benign esophageal strictures is a question of personal
preference. I find it equally easy to use Savary dilatiors or balloon dilators. No clear advantage of either
balloon or Savary dilation has been demonstrated.10, 11
12. Q: A) How common are Schatzki rings in the normal population? Is it clinically important to distinguish
between type A and B rings in clinical practice?
B) If a patient has dysphagia due to a large food bolus, but a gastroscope is easily passed through a Schatzki
ring, is there any role of dilation?
C) What is the best method to dilate a Schatzki ring? Should one use serial dilations or a single, one-time
dilation with a large-diameter bougie?
A: Most Schatzki rings have been reported to be mucosal rings (so-called “B” rings) and are located at the
esophagogastric junction, because the upper surface of the ring is covered with squamous epithelium and the
undersurface by columnar epithelium. Some muscular rings are covered with squamous epithelium on both
sides; these rings are located more proximally and are believed to represent the lower esophageal sphincter
(the so-called “A” ring). Lower esophageal (Schatzki) rings are seen in 5 to 10 percent of endoscopic
examinations, but symptomatic rings are seen in only 0.5 percent of examinations.8
If a patient with a Schatzki ring is symptomatic, even when the gastroscope can be passed, I perform Savary
dilation up to 18 to 20 mm. This is usually effective, and the risk of repeat dilation within one year is less
than 10 to 20 percent. I prefer serial dilations, because the sensed tightness during dilation with dilators
of increasing diameters helps guide the endoscopist to the maximal diameter that should be achieved
during the dilation session. I recommend that the presence of gastroesophageal reflux should be evaluated
with a 24-hour ambulator pHstudy in patients with (symptomatic) Schatzki rings, because an association
between gastroesophageal reflux and the presence of lower esophageal rings has been suggested. If reflux is
demonstrated, it should be treated.
continued on page 5
ASGE News March | April 2011 4
Ask the expert continued from page 4
13. Q: For Schatzki rings, is there a therapeutic role for using a needle-knife or bipolar probe?
A: In case of recurrent or refractory Schatzki rings, it is indeed advisable to use incisional therapy using a needle
knife, APC or IT knife. I recommend performing repeat dilation as the first-line treatment in Schatzki rings, with
incisional therapy performed as second-line treatment.
14. Q: What do you think is the best approach for treating symptomatic strictures or webs in a patient with
eosinophilic esophagitis (EE) that has been refractory to treatment with swallowed topical corticosteroids
and avoidance of allergens?
A: There are no published controlled trials of dilation therapy to guide clinicians as to when and how to perform
esophageal dilation for patients with EE. There is also no consensus regarding how long medical therapy should
be administered before resorting to esophageal dilation, nor is it clear which diet, medications or combinations of
medications and diet should be tried before a patient is deemed to be a failure of medical treatment. The results
of a recent review suggest that the risks of esophageal dilation for patients with EE may have been exaggerated.9
Nevertheless, I exercise caution in performing dilation in these patients.
15. Q: A patient presents with a stricture of the upper anastomosis of a jejunal interposition of the cervical
esophagus secondary to resected and radiated laryngeal cancer six years previously. The stricture needs
repeat dilation at six-week intervals and resists dilation with a dilator larger than 12.8 mm. The patient
has already had more than 25 dilation sessions. Is it possible to increase the luminal diameter safely and
effectively? How can the time interval between dilations be lengthened? Is there a method to maintain
long-term patency of the esophageal lumen?
A: Anastomotic strictures of the proximal esophagus are among the most difficult benign esophageal
strictures to treat. These strictures result from a state of chronic ischemia due to a reduced blood supply
at the anastomotic site. Previous radiation therapy at this site may have further reduced perfusion at
the anastomosis. Dilation of anastomotic strictures is in general safe, with a perforation risk of less
than 0.5 percent.
The patient presented here has a refractory stricture. I usually start dilating refractory benign anastomotic
strictures 2 to 3 times per week to ultimately establish a dilation diameter of 16 to 18 mm and then try to
reduce the frequency of dilations. I have a preference for Savary dilators over balloon dilators in refractory or
recurrent (anastomotic) strictures, because they allow me to have a feeling of the degree of resistance when
advancing the dilator.
If it is not possible to increase the frequency of dilation intervals, the next step in this algorithm1 is to perform
incisional therapy using a needle knife. It is important to incise anastomotic strictures deep enough to achieve
an acceptable luminal diameter. Although incisional therapy has not been shown to give better results than
dilation in the initial treatment for anastomotic strictures, it can be effective in more refractory strictures.2
If incisional therapy is also not successful, stent placement can be considered. Until now, only Polyflex stents
(Boston Scientific, Natick, Mass.) have been approved by the U.S. Federal Drug Administration (FDA) for
benign esophageal strictures. Many patients with anastomotic strictures do not, however, tolerate Polyflex
stents in this position due to their size. We use custom-made metal stents with sizes ranging from 10 to 14
mm.3 The temporary use of these stents could reduce the risk of complications by gradually increasing the
stent size.
When stent placement does not result in relief of dysphagia, I train patients to perform self-bougienage daily
using Maloney dilators, particularly when the stricture is in the cervical or proximal esophagus. Finally, a
surgical solution can be considered; however, the stricture may recur.
The information presented in Ask the expert reflects the opinions of the author and does not represent the position of ASGE. ASGE expressly
disclaims any warranties or guarantees, express or implied, and is not liable for damages of any kind in connection with the material,
information, or procedures set forth.
See next page for additional resources and references!
continued on page 6
ASGE News March | April 2011 5
Ask the expert continued from page 5
Additional resources
Chung, MD,
MD, Il-Kwun
Hyun Bok,
Gun Kim, MD,
Cho, MD, Gene Young Cho, MD, Hyun
Won
MD, Joo Young
Tae Hee Lee, MD, Youn Ho Jung, MD,
, Seoul, Korea
College of Medicine
Tae Hoon Lee, Joon Seong Lee, MD
University,
MD,
EARLY BIRD
, SoonChunHyang
can pose a
Jin Oh Kim,
practice and
Digestive Research
for REGISTRATION ENDS
Institute for
tered in clinical
first line therapy
g
APRIL 25!
e tract are encountherapy has become
ns regardin
digestiv
opic
upper
the
Endosc
l recommendatio
s
Strictures of
nterologist.
provides practica digestive tract stricture
the gastroe
s. This video
challenge to
nt of upper
pic treatme
malignant stricture
al therapy.
benign and
ues for endosco
and incision
and techniq
, stent therapy
indications
to:
dilation therapy
ns will be able
s
physicia
focusing on
stricture
onal activity,
used to treat
in this educati
that can be
of participating endoscopic therapies
As a result
t
differen
the
,
• Describe
and trainees
e tract.
nterology fellows
of the digestiv
ists, gastroe
gastroenterolog nurses.
e: Practicing
ts and
Target audienc s, physician assistan
ted by the
(ASGE) is accredi ing medical
medical resident
Endoscopy
continu
on to provide
Gastrointestinal
n Society for
Medical Educati
The America
Continuing
Council for
ry 1
Accreditation
PRA Catego
physicians.
of 1.25 AMA
of their
education to
a maximum
extent
for
the
onal activity
nsurate with
tes this educati only claim credit comme
ASGE designa
should
Physicians
CME
Credits™.
most current
in the activity.
DVD. For the
g Library.
participation
ded from this
opic Learnin
can be downloa
visit the Endosc
ge.org and
request form
A CME credit
1, 2013
log on to www.as
and forms,
on Date: May
information
CME Expirati
NON PROFIT
ORG
US POSTA
GE
PAID
PERMIT
#1096
CAROL STREAM
, IL
Strictur
es, Sten
ts
EARLY BIRD
REGISTRATION
ENDS
APRIL 25!
and Dila
tions
Hyatt Lodg Friday & Satu
rday,
e at McD
onald’s June 3-4, 2011
Campus,
Oak Broo
k, Illino
is
is
Friday &
Saturday,
e at McDo
June
nald’s Camp 3-4, 2011
us, Oak
Brook, Illino
Hyatt Lodg
r Digestive
May 1, 2010
1520 Kensing
Copyright 2010.
Tract
opy
ntestinal Endosc
353-ASGE(2743)
for Gastroi
USA | (866)
American Society| Oak Brook, IL 60523
202
www.asge.org
ton Road, Suite [email protected] | Web:
E-mail: educati
ASGE Masters Series Course
ASGE Interactive Training & Technology Center, Oak Brook, Ill.
Course Directors: Michelle A. Anderson, MD and John A. Dumot, DO
Course
.
All rights reserved
Stricture
s, Stents
Release Date:
Endoscopy
Therapeutic
of the
for Strictures
ve Tract
Upper Digesti
education@a · F 630.57
3.0691
www.asge.orgsge.org
of the Uppe
l Strictures, Stents and Dilations, June 3-4
ASGE
Endoscopic ry
Learning Libra
DV046
1520 Kensin
Oak Brook, gton Rd.
IL 60523
· Suite 202
73 minutes P 630.573.0600
for Strictures
Endoscopy
Therapeutic Endoscopy for Strictures of the Upper Digestive Tract
Endoscopic Learning Library DVD – 2010 Audiovisual Award Winner
Tae Hee Lee, MD, et al
DV046 1.25 CME Credits
Member price: $99; non-member price: $139
Total run time:
Therapeutic
l
for
Endoscopy
ct
Therapeutic
Digestive Tra
the Upper
Strictures of
Directo
rs
Michell
e A. And
erson, MD
John A.
Dumot,
DO
Invited
Faculty
Todd H.
Baron,
MD, FASG
James S.
E
Barth
Bipan Chand el, MD, FASG
E
, MD
Kulwinder
S. Dua,
MD, FASG
Ashley
L. Faulx
, MD, FASG E
Cyrus R.
E
Piraka,
MD
and Dila
tions
References
1. Siersema PD, de Wijkerslooth LR. Dilation of refractory benign esophageal strictures. Gastrointest Endosc 2009;70:1000-12.
2.Hordijk ML, Siersema PD, Tilanus HW et al. Electrocautery therapy for refractory anastomotic strictures of the esophagus.
Gastrointest Endosc 2006;63:157-63.
3.Conio M, Blanchi S, Filiberti R, et al. A modified self-expanding Niti-S stent for the management of benign hypopharyngeal
strictures. Gastrointest Endosc. 2007;65:714-20.
4.Mandelstam P, Sugawa C, Silvis SE et al. Complications associated with esophagogastroduodenoscopy and with esophageal
dilation. Gastrointest Endosc 1976;23:16-9.
5.Repici A, Hassan C, Sharma P et al. Systematic review: the role of self-expanding plastic stents for benign oesophageal strictures.
Aliment Pharmacol Ther 2010;31:1268-75.
6.Kadakia SC, Parker A, Carrougher JG, et al. Esophageal dilation with polyvinyl bougies, using a marked guidewire without the
aid of fluoroscopy: an update. Am J Gastroenterol 1993;88:1381-6.
7.Thomas V, Harish K, Sunilkumar K. Pneumatic dilation of achalasia cardia under direct endoscopy: the debate continues.
Gastrointest Endosc 2006;63:734.
8. Allescher HD, Storr M, Seige M, et al. Treatment of achalasia: botulinum toxin injection vs. pneumatic balloon dilation. A
prospective study with long-term follow-up. Endoscopy 2001;33:1007-17.
9. Jacobs JW, Spechler SJ. A systematic review of the risk of perforation during esophageal dilation for patients with eosinophilic
esophagitis. Dig Dis Sci 2010;55:1512–5.
10. Saeed ZA, Winchester CB, Ferro PS, et al. Prospective randomized comparison of polyvinyl bougies and through-the-scope
balloons for dilation of peptic strictures of the esophagus. Gastrointest Endosc 1995;41:189-95.
11. Scolapio JS, Pasha TM, Gostout CJ, et al. A randomized prospective study comparing rigid to balloon dilators for benign
esophageal strictures and rings. Gastrointest Endosc 1999;50:13-7.
ASGE News March | April 2011 6