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42 Part I Introduction
recommended to perform a brief but complete endoscopic
evaluation of the esophagus, stomach, and duodenum to
rule out any coexistent disease, which might require treatment or complicate the PEG procedure. e assistant then
presses on the abdomen with a single nger and the impact
against the anterior gastric wall should be noted. Ideally, this
point should be 2–3 cm below the costal margin and the
maximal point of impression may be on either side of the
abdominal wall or subxyphoid. Light transillumination from
within the stomach to the skin surface may aid in identifying a safe landmark. Finally, it is imperative to perform a
“safe tract” technique to assure that there is no intervening
hollow viscus between the stomach and anterior abdominal
wall. After anesthetizing the skin, a syringe with saline or
local anesthetic is passed through the abdominal wall at the
selected site while aspirating. As soon as air is appreciated in
the syringe, the tip of the needle should be simultaneously
visualized by the endoscopist in the gastric lumen. If not, an
alternative site needs to be selected.
e endoscopist now passes a polypectomy snare through
the endoscope channel at the selected intragastric site. A
small transverse incision (approximately 7–9 mm) in the skin
is created and the assistant then inserts a 14-gauge intravenous cannula through the incision into the gastric lumen.
e snare is then tightened around the cannula and the inner
stylet is removed.
“Pull” PEG. In the “pull technique,” a long looped suture is
placed through the cannula, after which the snare is released.
e suture is then rmly grasped with the polypectomy
snare. e endoscope and the tightened snare are removed
together, bringing the suture out of the patient’s mouth. e
suture is secured to a well-lubricated gastrostomy tube at its
tapered external end. e assistant then pulls on the suture
until the attached tube exits the abdominal wall. e endoscope is then reinserted and used to view the tube’s inner
bolster (Fig. 3-13) as the stomach is loosely seated against
the abdominal wall and the tube is properly positioned. is
second intubation of the endoscope can be aided by grasping the PEG bumper with the snare passed through the
endoscope. With withdrawl of the PEG through the mouth
and out the abdominal wall, the endoscope is reintroduced
into the esophagus. e snare is opened after esophageal
intubation. e external bumper is placed loosely so that
there is no tension at the PEG site and the endoscope is
then removed.
“Push” PeG. In the “push technique,” a guide wire rather
than a looped suture is inserted through the cannula and
pulled out the patient’s mouth. e gastrostomy tube,
called a Sachs-Vine tube, has a long tapered tip, which can
be pushed over the wire until it exits the abdominal wall. A
second endoscopic intubation is recommended similar to the
“pull” technique.
“Introducer” PeG. In the “introducer technique,” a guide
wire is passed through the cannula placed into the stomach
FIGURE 3-13 Second intubation is recommended after PEG place-
ment to conrm the position of the internal bumper and to exclude
any postprocedural bleeding.
under endoscopic guidance. An introducer with a peel-away
sheath is then passed over this wire, allowing removal of the
wire and introducer. A Foley catheter or other similar gastrostomy tube is then placed through the sheath, its balloon
is inated, and the sheath is removed. e catheter is then
secured to the abdominal wall. e placement of T-tags prior
to performance of the introducer PEG can help to secure the
stomach to the abdominal wall.
Laparoscopic-Assisted PEG. In patients with morbid obe-
sity, prior surgery, or intrathoracic gastric positioning, where
safe access cannot be adequately determined by routine endoscopic techniques, simultaneous laparoscopy and endoscopy
can be performed to complete the PEG safely. In this way, a
long spinal needle can be passed under direct laparoscopic view
from the abdominal wall into the gastric lumen and the PEG
can be completed as described above.
Interventional Radiology–Assisted PEG. In patients
with a “hostile” abdomen secondary to malignancy, multiple
prior surgeries, or obesity where safe access cannot be endoscopically determined and laparoscopy would be challenging, a percutaneous intragastric pigtail catheter can be placed
by interventional radiology under CT or ultrasound guidance. Utilizing a rendezvous technique, a guide wire is then
advanced through the pigtail during upper endoscopy, and the
PEG is completed.
PEG with Jejunostomy Tube Extension. In patients who
fail to tolerate gastric feedings due to severe gastroesophageal
reux or gastroparesis, transpyloric feeding can be provided via
a jejunostomy tube passed through the existing PEG. ere
are no prospective randomized trials, however, showing a difference between intragastric and transpyloric feeding, in terms
of incidence of aspiration pneumonia. e majority of cases of
Chapter 3 Endoscopy and Endoscopic Intervention 43
aspiration pneumonia are related to aspirated oropharyngeal
secretions in a patient unable to protect their own airway.
PEG-J placement is achieved by passing a jejunal feeding
tube through the PEG lumen (a 24 Fr PEG tube accommodates up to a 12.5 Fr J-tube; a standard 20 Fr PEG tube
accommodates an 8.5 Fr J-tube). Endoscopically, the jejunal
tube is guided into the duodenum under direct vision. A loop
suture on the tip of the jejunostomy tube can be grasped by
an endoscopic clip and once in the distal duodenum, the clip
is deployed onto the small bowel mucosa to secure the tube
in place. ese clips routinely fall o in 1–2 weeks, but this
technique allows for easier removal of the endoscope from the
duodenum without simultaneous inadvertent withdrawal of
the J-tube at the end of the procedure.
DIRECT PERCUTANEOUS ENDOSCOPIC
JEJUNOSTOMY TUBE
In patients with conrmed aspiration secondary to gastroesophageal reux of intragastric feedings, direct PEJ rather
than PEG-J is of benet. Feedings beyond the ligament of
Treitz are associated with a lower incidence of gastroesohpagealinduced aspiration as compared to simple postpyloric feed-
34
Direct PEJ, however, is associated with increased proce-
ing.
dural risks including bleeding, inadvertent viscus injury, and
35–38
leakage.
Performance of direct PEJ requires both endoscopic and uoroscopic guidance. Utilizing a pediatric colonoscope, the proximal jejunum is intubated and the tip of
the endoscope is uoroscopically visualized. Abdominal wall
depression with a haemostat is performed at this site to try
to identify a loop of small bowel adjacent to the abdominal
wall. Safe tract techniques are then used to access the identied bowel and a “pull” PEJ is performed with either a 16 Fr
or 20 Fr tube. Second intubation with the endoscope to the
PEJ site is mandatory to assure intraluminal positioning of
the jejunostomy tube bumper.
Foreign Body Extraction. Foreign bodies are ingested
predominantly by two groups of patients: children (ages
1–5 years) who accidentally swallow an object, and adults,
who are obtunded or inebriated, have a psychiatric disorder,
39,40
or are prisoners.
Food impaction may occur in patients
who have an underlying benign or malignant esophageal
stricture, or in patients with esophageal motility disorders.
41
Also, patients who are edentulous or have poor tting
dental prostheses are at risk for food impaction of poorly
chewed meat boluses. Evidence of respiratory compromise
or an inability to handle one’s own secretions indicates an
immediate need for endoscopic evaluation and extraction
of the object.
When performing endoscopic extraction, protection of
the airway is of vital importance. Endotracheal intubation
is required in patients who are unable to handle their own
secretions. An endoscopic overtube should be considered
when there is concern for dropping pieces into the airway
such as when removing sharp objects or multiple fragments.
In addition, practicing with a similar foreign body prior to an
attempted removal will allow for selection of the most appropriate endoscopic tool.
Coins represent the most object swallowed by children, and
if seen to be in the esophagus should be removed promptly
due to the risk of pressure necrosis and stula formation.
e coin is localized and grasped with a polypectomy snare,
net, or rat-tooth or tenaculum forceps. A Foley catheter is not
recommended since it does not control the object well during
removal and could become dislodged into the airway.
In the adult population, meat impaction represents the
most common foreign body and should be removed if they
remain for longer than 12 hours due to the risk of pressure
41
necrosis.
Gentle scope advancement at the level of the
obstruction can many times assist in passage of the food
bolus. Piecemeal removal with baskets, nets, and snares may
be needed, with care being taken to avoid passage of the foreign body into the airway. If the bolus should pass, EGD is
still indicated to rule out an associated esophageal lesion.
Use of an overtube or protective endoscopic hood may
greatly facilitate removal of sharp objects such as tooth-
removing sharp objects it is important to follow the tenet
of always having the sharp end trailing. If necessary, sharp
objects can be carefully pushed into the stomach, rotated, and
then brought out with the pointed end trailing.
Ingested button batteries must be removed immediately to
prevent viscus injury secondary to a corrosive burn. ese batteries usually pass readily in other parts of the gastrointestinal
tract without causing harm, although all mucosal surfaces must
be examined endoscopically to identify any resultant injury.
When encountered, cocaine-lled packets should never be
removed endoscopically because of the risk of breakage. Close
observation and expectant management is more appropriate,
with expedient surgical intervention for any signs of bag rupture or bowel obstruction.
Following any foreign body removal, the endoscopist
must exclude any associated underlying disease such as stricture, neoplasm, or motility disorder (Fig. 3-14). In addition,
one must be aware of the possibility of delayed viscus injury
secondary to pressure necrosis resulting in partial or full
thickness injury. Emergent contrast study or CT should be
used as needed to evaluate for these complications. Repeat
endoscopy, motility study, or elective contrast studies may
also be required based on patient’s history or continued
symptoms.
Other nonobstructing foreign bodies may be identied
in postsurgical patients. Intraluminal suture migration may
lead to symptoms of pain or dysphagia. (Fig. 3-15). Removal
with endoscopic scissors may relieve the patient’s symptoms
of pain or dysphagia.
Endoscopic Dilation. Endoscopic dilation can be per-
formed for any enteral stricture that can be accessed by endoscopic means. e endoscopic component of dilation may
include identication, passage of a guide wire, or delivery of
a dilating balloon via the endoscope channel. Strictures secondary to ischemia, inammation, radiation, neoplasm, and
39
41
44 Part I Introduction
FIGURE 3-14 Classic eosinophilic esophagitis seen in a patient
with history of dysphagia and prior food bolus. Endoscopic biopsies
with identication of increased eosinophils conrms the diagnosis.
postsurgery are all amenable to endoscopic dilation. e use
of uoroscopy as an adjunct to endoscopic dilation is believed
to decrease the risk of perforation, although this has not been
fully proven in randomized prospective trials.
the type of sedation utilized is dependent on the clinical status of each individual patient, as those with tight esophageal
strictures may be best served with elective airway protection.
42
In addition,
Although several types of dilators have been used, the
two most common dilators used are the guide wire–driven
type, which applies both axial and radial forces, and the balloon type, which applies only radial forces. Treatment is safer
when performed by incremental dilations over successive sessions. A general approach is to limit the number of dilations
to three successive balloon or dilator sizes in one session.
Injection of steroid solutions (kenalog) into the stricture
may reduce the severity of postdilation inammation, scarring, and restricture. e frequency of dilation will depend
on the severity of the stricture and the patient’s symptoms.
Balloon dilators are used for short strictures, stenotic stomas,
and achalasia. ese dilators can be passed over a previously
placed guide wire, and are delivered through the endoscope’s
therapeutic channel. Fluoroscopic guidance for balloon dilation
allows the endoscopist to gauge several components of the procedure. First, it assures the positioning of the balloon in the
viscus lumen. Second, if contrast is injected in the balloon as the
dilating uid, expansion of the balloon fully can be appreciated.
is is termed “waist ablation” and refers to the full dilation of
the balloon at the site of the stricture. e balloon changes from
an hour glass appearance to a full elliptical-shaped gure.
Long, complex strictures may be less responsive to endoscopic dilation, and may also require repeat treatments. Aggressive biopsing of the mucosa after dilation is necessary in cases
of unclear etiology. Complications secondary to endoscopic
dilation include bleeding, perforation, mucosal tears, and
recurrent structuring.
Enteral Stent Placement. Over the past several years,
endoscopic stent technology has made impressive strides in
providing tools for increasingly complex clinical scenarios.
Both the delivery systems and the stents themselves have gone
through signicant changes and allowances for treatment of
a multitude of benign and malignant disease processes. Strictures, leaks, stulae, and obstructing neoplasms have all been
approached with enteral stents.
43–50
FIGURE 3-15 Sutures can be seen at the site of a prior gastrojeju-
nostomy.
Stent Delivery Systems. Based on the location of the gas-
trointestinal tract that is to be treated, as well as the characteristics of the stent desired, endoscopic stent deployment is
either through-the-scope (TTS), or wire guided. TTS stents
are delivered through the endoscope channel and are routinely a 10 Fr system and require a therapeutic scope. Only
uncovered self-expanding metal stents (SEMS) have a TTS
characteristic. e remainder of stents all utilize wire guided
systems and are placed under uoroscopic guidance. Stent
delivery systems are further categorized as proximal or distal
deploying based on which end of the stent is opened rst. In
patients undergoing stent placement in the proximal esophagus, proximal deploying stents are preferred. Otherwise, most
stent systems utilize a distal deployment pattern. Non-TTS
stents are limited to the esophagus including the esophagogastric junction. In patients following gastric resection, these
systems can also traverse a gatrojejunal anastomosis. TTS systems, conversely, can reach any site in the gastrointestinal tract
that can be accessed by a therapeutic endoscope.
43
Chapter 3 Endoscopy and Endoscopic Intervention 45
Stent Characteristics. Covered endoscopic stents have
been created for the sole purpose of temporarily bridging
esophagaeal and proximal anastomotic leaks and stulae.
45
e fully covered nature of the stent impedes tissue ingrowth
as would occur with an uncovered enteral stent, and thereby
allows removal after 2–3 months once the stula has been
cured. With the increased frequency of bariatric procedures,
anastomotic complications secondary to Roux-en-Y bypass
are routinely managed with placement of endoscopic stents.
Removable stents are subdivided into plastic or hybrid
based on the underlying structural platform. As stated
above, fully covered silicone stents which are self-expandable
but require the use of a large deployment system, can
reach as far as the proximal stomach. Similarly, covered
SEMT (hybrid) are also placed outside of the endoscope
under uoroscopic guidance, and can reach the proximal
stomach as well. e greatest problem with these stents
45
is the high risk of migration.
If placed across a gastrojejunostomy, this can result in small bowel impaction of
a migrated stent, resulting in the need for surgical extirpation. Bleeding, perforation, and obstruction are far less
common complications.
Uncovered enteral stents, utilizing TTS deployment systems, are not intended for removal and can be placed for
temporary relief of benign and malignant strictures through-
43,44,46–48
out the gastrointestinal tract.
ey are associated with
increased tissue ingrowth and occlusion as compared to covered stents, but have a lower rate of migration. In unresectable
disease states, palliation of obstruction with enteral stents can
provide an alternative to surgical bypass procedures. In addition, endoscopic stent placement in patients with obstructing colon lesions can allow for immediate decompression
followed by semielective resection and primary anastomosis,
rather than an initial diverting stoma.
49,50
some of the short-term results were promising, the longterm results were bleak, conrming the lack of durability of
a mucosa-to-mucosa apposition. is product is not presently being marketed for GERD treatment. Most authorities
agree that technical renements would be necessary before
the EndoCinch can be eectively used for gastroplication.
STRETTA (CURON MEDICAL, SUNNYVALE CA)
is is the only device that involves delivery of radio frequency energy to the lower esophageal sphincter (LES)
muscles. Multiple applications at several levels are required to
complete the treatment. e procedure is performed blindly
after endoscopically conrming the location of the LES. e
intention is to induce collagen deposition to the LES, thereby
adding more bulk and reducing the compliance of the LES.
e eects are generally not immediate, but are realized over
time. Despite modest success with this device, the company
declared bankruptcy in 2007.
53–57
PLICATOR (NDO SURGICAL, MANSFIELD MA)
e NDO endoscopic plication system (NDO Surgical,
Inc, Manseld, MA) performed serosa-to-serosa apposition
of the stomach just distal to the esophagogastric junction.
e reusable device included a suturing mechanism at its
tip and a channel for passage of a small bore endoscope for
visualization. e single-use suturing implant used pretied
polypropylene sutures with polytetrauoroethylene bolsters.
A proprietary retraction device selected the tissue for plication before deploying the sutures with a turn of the handle.
Similar to Curon, this company also had signicant nancial
diculties and declared bankruptcy in 2008.
58–61
51,52
Endoluminal Treatment of GERD
Numerous endoluminal treatments for gastroesophageal
reux disease (GERD) have been introduced over the past
10 years and have had varied clinical success. ese technologies were based on either suturing, tissue bolstering, or
energy delivery. Unfortunately, due to many factors including marginal patient improvement, limited physician acceptance, severe complications, and corporate nancial diculties, most of these treatments are not presently available in
the United States. Examples of each of these modalities are
described below.
ENDOCINCH (BARD, BILLERICA, MA)
e EndoCinch plication device (CR Bard, Inc, Murray
Hill, NY) creates an internal mucosa-to-mucosa placation of
the stomach. Using a standard endoscope outtted with the
device at its tip, the tissue is drawn into the suturing chamber
by suction, and two sutures are placed. e knots are formed
extracorporally and advanced to the gastric mucosa. While
ENTERYX (BOSTON SCIENTIFIC CORP, NATICK, MA)
For augmentation of the LES, the Enteryx system used a biocompatible, nonbiodegradable polymer. e solution contained a liquid polymer and radiopaque material to gauge the
depth of injection. A circumferential injection of the polymer
is performed, and its subsequent solidication tightens the
esophagogastric junction. Multiple recent studies employing
the Enteryx system have been published. Of note, Deviere
and colleagues described the rst sham-controlled trial with
62
Enteryx in 2005.
Of the 64 patients, 83% reduced proton
pump inhibitor (PPI) use by 50%, and 68% had discontinued PPIs. However, in the sham arm, 53% had halved their
PPI use, and 40% discontinued PPIs. ere was no objective
improvement in pH values. Due to severe adverse events related
to intra-aortic injections and subsequent fatal stulization, the
product was voluntarily discontinued by the company.
62–68
GATEKEEPER (MEDTRONIC, INC,
MINNEAPOLIS, MN)
e Gatekeeper reux repair system alters esophagogastric
junction anatomy in order to restrict the aperture for reux.
46 Part I Introduction
A saline lift is performed above the squamocolumnar junction, and a biocompatible cylindrical prosthetic composed of
polyacrylonitrite hydrogel is placed in the submucosa. e
prosthetic subsequently enlarges with hydration, thereby
impeding gastroesophageal re ux. ere were two signi cant
complications and the manufacturer has since withdrawn the
69,
Gatekeeper system from the market.
ESOPHYX (ENDOGASTRIC SOLUTIONS,
REDWOOD CITY, CA)
70
EsophyX is a novel endoluminal fundoplication technique
using a trans-oral fastener-deploying device, attempting to
mimic a Nissen fundoplication. In a feasibility study from
Belgium, the results at 2 years supported long-term safety
and durability with a sustained e ect on the elimination of
heartburn, esophagitis, hiatal hernia, and daily dependence
on PPIs. At 2 years, no adverse events were reported, and
a 50% or greater improvement in GERD-HRQL scores as
compared with baseline on PPIs was sustained by 64% of
patients. Esophyx was e ective in eliminating heartburn in
93% of patients and daily PPI therapy in 71% of patients.
Further clinical trials directly comparing this procedure to
53
medical or surgical therapy are still necessary.
ENDOSCOPIC RETROGRADE
CHOLANGIOPANCREATOGRAPHY
History
TABLE 3-2: INDICATIONS FOR
ENDOSCOPIC RETROGRADE
CHOLANGIOPANCREATOGRAPHY
1. Suspected choledocholithiasis
2. Identi cation and management of malignant or benign
strictures
3. Investigation of abnormal radiographic imaging of the biliary
tree
4. Persistent jaundice
5. Evaluation and treatment of sphincter of Oddi dysfunction
(SOD)
6. Evaluation and treatment of pancreatic or biliary ductal injury/
trauma or leaks
7. Treatment for identi ed ampullary adenoma
8. Recurrent or idiopathic pancreatitis
9. Treatment of complications of chronic pancreatitis including
stones and/or strictures
10. Treatment for pancreatic uid/cyst or pancreatic necrosis
11. Cytology of suspected pancreatic cancer and other pancreatic
malignancies
patients undergoing bariatric procedures (Roux–en-Y gastric bypass) increases, access to the ampulla has become
more challenging. Identi cation and access to the remnant
stomach routinely require surgical or radiologic intervention for performance of ERCP.
William McKune, a surgeon, along with Paul Shorb, a gastroenterologist, were the rst physicians to perform ERCP.
In 1968, they reported on four cases of endoscopic identi cation and catheter placement into the ampulla of Vater. For
the rst time, imaging of the pancreatic ductal system could
be seen and utilized for diagnostic purposes. Several years
later in the mid-1970s, German and Japanese physicians
described their experience in endoscopic sphincterotomy,
the rst therapeutic extension of ERCP. Other endoscopic
adjuncts including stone lithotriptors, plastic and expandable metal stents, and intraductal imaging tools have fully
changed ERCP from a diagnostic tool into one that is predominantly therapeutic.
Indications
ere are numerous indications for ERCP as listed in
Table 3-2 . ERCP, however, is preferentially used as a
therapeutic tool due to the high risk of serious complications.
pancreticobiliary tree is desired, magnetic resonance cholangiopancreatography (MRCP) should be utilized.
to cholecystectomy for symptomatic cholelithiasis, the
presence of persistent jaundice or cholangitis is the indication for preoperative ERCP. Finally, as the number of
71
In patients where a diagnostic imaging of the
72
Prior
Patient Preparation
Patient preparation, sedation, and monitoring for ERCP
are similar to those for other upper endoscopic procedures,
although the patient is routinely placed in the prone positon.
Patients may require general anesthesia for airway protection,
inability to tolerate conscious sedation, for expected lengthy
or more complicated ERCP interventions, or in the presence
of multiple comorbid diseases. ERCP can be performed in a
supine position although this can make the procedure more
challenging, as in patients undergoing ERCP at the time of
laparoscopic cholecystectomy.
Techniques of ERCP
ERCP is performed using a side-viewing scope and requires
both endoscopic and uoroscopic skills for interpretation
and intervention. As stated above, ERCP is predominantly a
therapeutic technique. e scope is initially passed into the
esophagus blindly to a position beyond the upper esophageal sphincter and then rapidly advanced into the proximal
stomach where any residual secretions should be aspirated
Unlike a forward-viewing endoscope, the pylorus cannot
be visualized during intubation with a side-viewing scope.
Chapter 3 Endoscopy and Endoscopic Intervention 47
Upward deection of the side-viewing endoscope with
continued advancement will allow easy passage into the
duodenal bulb.
To manipulate around the superior duodenal angle, the
endoscope is turned to the right, and the tip is deected
upward to reach the second portion of the duodenum. e
endoscope is then withdrawn during this maneuver, leaving
the scope in the ideal “short-scope” position.
With the “short-scope” position, the endoscopist views
the papilla directly along the medial duodenal wall. Very
minute movements of the tip and further withdrawl of the
scope will bring the papilla into view. Intermittent doses
of glucagon can be given to minimize duodenal peristaltic
contractions. Dosing with glucagon, however, can lead to
increased postprocedure nausea and vomiting. Fluoroscopy
can also be used to determine appropriate scope position
and to help identify the site of the major papilla. After
the papilla is visualized, it is then cannulated using one
of the various types of catheters available. As the majority of ERCP cases are potentially of a therapeutic nature,
most endoscopists will start with a pull wire sphincterotome. Guide wire–assisted cannulation has also become a
popular practice for several reasons. First, it may minimize
the overall volume of contrast required, thereby hopefully
decreasing the rates of pancreatitis and cholangitis. Second,
FIGURE 3-16 An impacted common bile duct stone seen extruding
through the ampulla. is is best treated by needle knife sphincterotomy to allow release of the stone.
it may increase the eciency of selectively cannulating the
desired duct. Finally, it can help maintain access into the
duct during catheter exchanges.
Selective cannulation of the biliary and pancreatic ducts
depends on the angle of the catheter and the position of the
scope tip. e pancreatic duct tends to enter the papilla in a
relatively perpendicular fashion at the 1-o’clock position. In
contrast, the bile duct runs toward 11 o’clock below the “lip”
of the papilla.
ERCP represents an endoscopic and radiographic intervention, and proper radiologic technique is critical to obtaining interpretable radiographs. Artifacts such as air bubbles,
streaming and layering of contrast, and contrast spillage into
the duodenum should be recognized and avoided.
Once proper selective ductal cannulation is veried,
the sphincterotome is withdrawn until approximately half
of the wire is visible outside of the papilla (Figs. 3-17 and
3-18). Biliary or pancreatic sphincterotomy can be done as
needed. Indications for sphincterotomy include treatment
of sphincter of Oddi dysfunction (SOD), improved access
for stone removal or stent placement, and recurrent pancretitis. To perform sphincterotomy, the pull-wire is tightened,
bowing it against the papillary roof. Current is then applied
while maintaining gentle upward force on the wire and gently lifting the sphincterotome, making the incision in small
increments.
ERCP Therapeutic Interventions
SPHINCTEROTOMY
ere are two types of sphincterotomy that can be performed, needle knife sphincterotmy (precut sphincterotmy) or pull wire sphincterotomy. Needle knife sphincterotomy is performed when deep selective canulation is
unable to be obtained, and can be done over a previously
placed stent or guide wire, or when an impacted common
bile duct (CBD) stone is protruding through the ampulla
(Fig. 3-16). is technique is more technically challenging
and also has a higher risk of bleeding, pancreatitis, and
perforation. Pull wire sphincterotmy, conversely, requires
deep selective canulation with or without previous wire
placement.
MANAGEMENT OF CHOLEDOCHOLITHIASIS
Retained or recurrent CBD stones represent the most common indication for endoscopic sphincterotomy, and ERCP
with sphincterotomy successfully treats 95% of these cases.
73
In expert hands, over 90% of bile ducts can be successfully
cleared of calculi with balloon catheters or Dormia baskets,
resulting in an overall ductal clearance rate approximating
85% (Figs. 3-19 and 3-20). Stone size is often a limiting
factor, as stones greater than 2 cm in diameter often require
fragmentation prior to removal. e other reasons for unsuccessful ERCP include patient intolerance, inability to identify
or access the papilla, and inability to selectively canulate the
desired duct.
Routine preoperative ERCP and sphincterotomy are
not warranted in patients undergoing biliary operations for
48 Part I Introduction
FIGURE 3-17 Following deep selective cannulation of the bile duct,
a sphincterotomy is performed with a pull-wire sphincterotome.
FIGURE 3-19 ERCP radiographic image of a distal common bile
duct stone.
MANAGEMENT OF SOD
symptomatic cholelithiasis.73 Unfortunately, determining the
presence of CBD stones is challenging, as ultrasound ndings
of biliary dilation, elevation of liver function tests (LFTs),
and clinical factors such as pancreatitis are not always predictive of CBD stones. Only the actual radiographic nding of
choledocholithiasis is statistically associated with the actual
presence of CBD stones. As stated above, ERCP should rarely
be utilized as a diagnostic procedure.
74
SOD represents a broad range of symptoms including pain,
biliary colic, altered liver function tests, ductal dilation
with delayed drainage, and elevated sphincteric pressures.
Based on the number of associated symptoms, the response
to endoscopic sphincterotomy can be predicted. is disease also has a close association with gallbladder dyskinesia,
and may represent a parallel process in that many patients
FIGURE 3-18 Postsphincterotmy image of the major papilla.
FIGURE 3-20 Following sphincterotmy (seen in the upper right-hand
portion of the image) and balloon sweeping, the extracted common bile
duct stone is seen in the duodenum.
Chapter 3 Endoscopy and Endoscopic Intervention 49
following cholecystectomy for gallbladder dyskinesia will
eventually be suspected of also having SOD. While multiple noninvasive tests have been evaluated in this disorder
(eg, ultrasonography and scintigraphy), they all appear to
lack adequate sensitivity or specicity. e development
of endoscopic manometric techniques now allows direct
measurement of motility and intraluminal pressures within
both the biliary and pancreatic segments of the sphincter of
75,76
Oddi.
e common thread in patients with this disorder is
elevated basal sphincter pressure. Criteria for abnormal
manometry include basal pressure >40 mm Hg, peak sphincter pressure >240 mm Hg, >50% retrograde contractions, no
relaxation with cholecystokinin administration, and contraction waves >8 per minute. Sphincter of Oddi manometry is
technically challenging to perform and carries a high rate of
post-ERCP pancreatitis. In addition, any ERCP intervention
on patients with suspected SOD is associated with higher
rates of postprocedural pancreatitis.
75
FIGURE 3-21 ERCP revealing extravasation of contrast from an
accessory duct leak.
MANAGEMENT OF ACUTE CHOLANGITIS
79–82
Endoscopic biliary drainage has now been clearly shown to be
the procedure of choice for patients with acute suppurative
cholangitis. In critically ill patients, simple endoscopic stenting or nasobiliary drainage, with or without sphincterotomy,
should be performed. Complete clearance of the duct is not
necessary as long as drainage had been achieved. Stone extraction can be performed after the patient has stabilized, at the
time of stent removal 4–6 weeks later.
stent placement for pancreatitis protection.
with biliary stulae, the goal of the stent is to equilibrate the
biliary and duodenal pressures to facilitate closure of the leak
(Figs. 3-21 to 3-23).
Initially, a diagnostic cholangiogram or pancreatogram
is obtained to identify the lesion’s extent and to determine
the length of endoprosthesis required, and a guide wire is
maintained. If desired, a sphincterotomy can then be per-
In patients
formed to facilitate subsequent manipulations, although
stent placement can be performed without this maneuver.
MANAGEMENT OF ACUTE GALLSTONE
PANCREATITIS
Patients with biliary pancreatitis can typically be managed
Ideally, the endoprosthesis will be located with its upper ap
above the stricture and its lower ap just outside the papilla,
although suprapapillary placement of metal stents is routinely
conservatively, saving ERCP for those patients with worsening
pancreatitis or concommittant evidence of biliary obstruction
77
secondary to choledocholithiasis.
In these cases, early ERCP
and sphincterotomy can signicantly reduce morbidity and
77,78
mortality.
e majority of patients who develop gallstone
pancreatitis will have spontaneous passage of the CBD stone
without intervention. Laparoscopic cholecystectomy should
then be performed in the near future to prevent recurrence.
Conversely, patients who are not an operative candidate,
ERCP and sphincterotomy are eective in minimizing the
risks of pancreatitis, but obviously will have no eect on
the development of gallbladder complications related to the
cholecystolithiasis.
ENDOPROSTHESIS INSERTION
Currently available endoprostheses or stents vary in their
composition, shape, size, length, deployment system, and
method of anchorage. e indications for stent insertion
include cholangitis, benign/malignant biliary or pancreatic duct stricture, biliary or pancreatic duct leak, retained/
unremovable CBD stones, and prophylactic pancreatic duct
FIGURE 3-22 Following a 6-week course of biliary stenting, the
leak has resolved.
50 Part I Introduction
FIGURE 3-23 Transpapillary biliary stent placement for treatment
of the biliary leak.
FIGURE 3-24 Distal common bile duct stricture secondary to a
pancreatic head malignancy.
performed for more proximal malignant strictures. Transpapillary positon of plastic stents serves a function to ease
removal as well as equilibrating biliary and duodenal pressures in cases of bile duct leaks.
All biliary and pancreatic stents are placed using TTS
deployment systems. e diameters of these delivery systems vary based on the type of stent and the actual diameter
of the stent. Straight biliary and pancreatic plastic stents
come in 3, 4, 5, 7, 10, and 11.5 Fr diameters. For SEMT,
a special delivery system is used to insert the stent in a collapsed state (10 Fr diameter). After release, there is shortening of the SEMS as the stent expands to its full diameter
(8–10 mm).
80,81
Straight plastic biliary stents are temporary and must be
79
changed every 3–6 months.
Obstructive jaundice and cholangitis are common sequelae of occluded stents. Placing multiple stents may increase the length of overall patency, as bile
can traverse around and between the stents even if the stent
lumen becomes obstructed. SEMS carry a longer patency rate
80,81
of 9–12 months as compared to plastic stents.
Uncovered
metal stents are less likely to migrate as compared to covered
ones, but have a shorter patency rate due to the allowance for
ingrowth of tissue or tumor. Newer fully covered self-expanding
metal biliary stents also allow for delayed removal, and can
therefore be used in the management of chronic benign
strictures.
Patients undergoing endoscpic palliation for obstructive
jaundice secondary to malignancy who are not operative candidates may be better served with SEMS rather than plastic
stents due to the decreased need for repeat endoscopic inter-
80
vention in patients with a limited life expectancy.
If patients
have both a biliary and duodenal obstruction secondary to
malignancy, it is important to place the biliary SEMS prior
to the duondenal stent as access to the papilla beomes very
44
challenging.
Palliation of unresectable malignant biliary
obstruction in elderly high-risk patients appears to be one
of the most signicant indications for biliary endoprostheses
(Fig. 3-24).
In addition to biliary disorders, ERCP has been employed
in the management of benign and malignant pancreatic disorders. Pancreatic duct stenting can be used successfully to
decompress the ductal system, to bypass ductal leaks and
strictures, and to treat pancreatic stulas. Patients with pancreatic divisum may be treated with minor papilla stenting
or sphincterotomy. Pancreatic stents are smaller than biliary stents and they contain side holes for drainage. Pancreatic duct stents also can be placed in patients with high
risk for post-ERCP pancretitis including SOD, idiopathic/
autoimmune pancreatitis, and those having had a complex
ERCP with extensive pancreatic or bile duct manipulations
75
(Figs. 3-25 and 3-26).
Pancreatic duct stents should be
endoscopically removed within 2–3 weeks due to the risk
of ductal inammatory changes, whereas biliary stents can
be used indenitely and changed when there is evidence of
obstruction. On many occasions, the pancreatic stents will
pass spontaneously.
PANCREATIC DUCT STONES
ERCP for pancreatic ductal stone extraction is technically
more challenging and is associated with a higher risk of
complications such as pancreatitis. Some clinicians have
reported success with the use of mechanical lithotripsy,
contact lithotripsy, and/or extracorporeal shock wave lith-
83
otripsy to manage pancreaticolithiasis.
Pancreatic duct
stones routinely are harder than biliary cholesterol-based
stones and these patients may eventually require surgical
intervention.
Chapter 3 Endoscopy and Endoscopic Intervention 51
Ifwire access can be obtained via the pancreatic duct into the
cyst cavity, a pancreatic stent can be placed to allow for drainage of the cystic cavity. Although this may result in initial
resolution of the cyst, a high recurrence rate exists due to the
continued communication to the ductal system. After drainage, subsequent stenting of the pancreatic duct across the site
of leakage may be required.
Pancreatic pseudocysts directly adjacent to an endoscopi-
cally approachable lumen (ie, stomach, duodenum) may be
84–87
amenable to a transvisceral approach.
Assuring maturity of the cyst, absence of concern for neoplasm, and no
evidence of actual infection are important factors to determine prior to endoscopic drainage. e use of EUS is an
invaluable adjunct to this procedure for several reasons.
85,87
It can rule out intervening organs or vasculature, determine
if there is extensive debri rather than simple uid collections,
and assure proximity of the cyst to the selected viscus. EUS
FIGURE 3-25 Radiographic image of a pancreatic duct wire prior
to stent placement.
aspiration followed by guide wire placement is followed by
tract dilation and eventual pigtail stent placement. Stents are
removed in 6–12 weeks after conrming resolution of the
pseudocyst.
Patients with pancreatic necrosis rather than simple
ENDOSCOPIC PSEUDOCYST DRAINAGE/
NECROSECTOMY
e management of pancreatic pseudocysts and necrotic
debri is one of the more recent advances in the therapeutic
armamentarium of the endoscopist. Pancreatic pseudocysts
can be approached in a transpapillary or a transvisceral fashion based on the location and nature of the pseudocyst. Many
pseudocyst formation have also been approached endoscopi-
88–92
cally.
Similar to transvisceral cyst drainage, EUS guidance
is used to conrm the presence of a collection of debri, and
following tract dilation, the endoscope is advanced directly
into the adjacent cavity. Tissue is then removed using a
combination of irrigation/suction and snare/basket tissue
debridement. Stents are placed to maintain the tract to allow
for serial debridement of the necrotic tissue.
pseudocysts have direct connection to the main pancreatic
duct, and are referred to as “communicating” pseudocysts.
FIGURE 3-26 Temporary plastic 5 Fr pancreatic stent in place.
Complications of ERCP
POST-ERCP PANCREATITIS
e occurrence of ERCP-induced pancreatitis is associated
with both procedural factors and patient factors. Although
the precise factor leading to postprocedural pancreatitis has
yet to be elucidated, many factors including complex interventions including manometry, multiple pancreatic canulations or injections, excess delivery of thermal energy, and
placement of covered SEMS have all been implicated. Prophylaxes with antibiotics, steroids, somatostatin, xanthine
oxidase inhibitors, and immunologic agents such as IL-1
have been investigated in multiple prospective comparative trials without success in reduction of pancreatitis.
Patient factors associated with pancreatitis include SOD,
idiopathic pancreatitis, and the prior history of acute or
93
chronic pancretitis.
e use of short-term prophylactic
pancreatic stent placement may eventually be proven benecial in patients following higher risk procedures, or who
have comorbid disease states increasing their risk for postERCP pancreatitis.
75
Bacteremia or sepsis following ERCP, similar to pancre-
atitis, is secondary to procedural factors as well as underlying
93
patient factors.
Patients undergoing ERCP for obstructive
74,93