2388 PART 10 Disorders of the Gastrointestinal System

FIGURE 322-3 Normal upper endoscopic examination. A. Esophagus. B. Gastroesophageal junction. C. Gastric fundus. D. Gastric body. E. Gastric antrum. F. Pylorus.

G. Duodenal bulb. H. Second portion of the duodenum.

A B

C D

E F

2389 Gastrointestinal Endoscopy CHAPTER 322

FIGURE 322-4 Duodenal ulcers. A. Ulcer with a small, flat, pigmented spot in its base. B. Ulcer with a visible vessel (arrow) in a patient with recent hemorrhage.

FIGURE 322-5 Gastric ulcers. A. Benign gastric ulcer in the antrum. B. Malignant gastric ulcer involving greater curvature of stomach.

G H

A B

A B

FIGURE 322-3 (Continued)

2390 PART 10 Disorders of the Gastrointestinal System

FIGURE 322-7 Colonoscopic view of terminal ileum. A. Normal-appearing terminal ileum (TI). B. View of normal villi of TI enhanced by examination under water immersion.

A B

C D

FIGURE 322-6 Barrett’s esophagus. A. Salmon-colored Barrett’s mucosa extending proximally from the gastroesophageal junction. B. Barrett’s esophagus with a suspicious

nodule (arrow) identified during endoscopic surveillance. C. Histologic finding of intramucosal adenocarcinoma in the endoscopically resected nodule. Tumor extends into

the esophageal submucosa (arrow). D. Barrett’s esophagus with locally advanced adenocarcinoma.

A B

>95% of cases, and the terminal ileum (Fig. 322-7) can often be examined. Colonoscopy is the gold standard for imaging the colonic mucosa

(Fig. 322-8). Colonoscopy has greater sensitivity than barium enema

for colitis (Fig. 322-9), polyps (Fig. 322-10), and cancer (Fig. 322-11).

CT colonography rivals the accuracy of colonoscopy for detection of

some polyps and cancer, although it is not as sensitive for the detection

of flat lesions, such as serrated polyps (Fig. 322-12). Moderate sedation is usually given before colonoscopy in the United States, although

a willing patient and a skilled examiner can complete the procedure

without sedation in many cases.

■ FLEXIBLE SIGMOIDOSCOPY

Flexible sigmoidoscopy is akin to colonoscopy, but it visualizes only

the rectum and a variable portion of the left colon, typically to 60 cm

from the anal verge. This procedure causes abdominal cramping, but

it is brief and usually performed without sedation. Flexible sigmoidoscopy is primarily used for evaluation of diarrhea and rectal outlet

bleeding.

■ SMALL-BOWEL ENDOSCOPY

Three endoscopic techniques are currently used to evaluate the small

intestine, most often in patients presenting with presumed smallbowel bleeding. For capsule endoscopy, the patient swallows a disposable capsule that contains a CMOS chip camera. Color still images

(Fig. 322-13) are transmitted wirelessly to an external receiver at

several frames per second until the capsule’s battery is exhausted

or it is passed into the toilet. Capsule endoscopy enables visualization of the small-bowel mucosa beyond the reach of a conventional

2391 Gastrointestinal Endoscopy CHAPTER 322

FIGURE 322-8 Normal colonoscopic examination. A. Cecum with view of appendiceal orifice. B. Ileocecal valve. C. Normal-appearing colon. D. Rectum (retroflexed view).

A B

C D

endoscope, and at present, it is solely a diagnostic procedure. Patients

with a history of prior intestinal surgery or Crohn’s disease are at risk

for capsule retention at the site of a clinically unsuspected smallbowel stricture, and ingestion of a “patency capsule” composed of

radiologically opaque biodegradable material may be indicated prior

to capsule endoscopy in such patients.

Push enteroscopy is generally performed using a variable-stiffness

pediatric or adult colonoscope or a dedicated enteroscope with or without the assistance of a stiffening overtube that extends from the mouth

to the small intestine. The proximal to mid-jejunum is usually reached,

and the instrument channel of the endoscope allows for biopsy or

endoscopic therapy.

Deeper insertion into the small bowel can be accomplished by

device-assisted enteroscopy, which may utilize inflatable balloons at

the tip of the enteroscope and/or an overtube (single- or doubleballoon enteroscopy) or a rotating, screw-like overtube (motorized

spiral enteroscopy) to pleat the small intestine onto the endoscope

(Fig. 322-14, Video V5-1). With device-assisted enteroscopy, the

entire small intestine can be visualized in some patients when both

the oral and anal routes of insertion are used. Biopsies and endoscopic therapy can be performed throughout the visualized small

bowel (Fig. 322-15).

■ ENDOSCOPIC RETROGRADE

CHOLANGIOPANCREATOGRAPHY

During endoscopic retrograde cholangiopancreatography (ERCP), a

side-viewing endoscope is passed through the mouth to the duodenum, the ampulla of Vater is identified and cannulated with a thin plastic catheter, and radiographic contrast material is injected into the bile

duct and pancreatic duct under fluoroscopic guidance (Fig. 322-16).

When indicated, the major papilla can be incised using the technique of endoscopic sphincterotomy (Fig. 322-17). Stones can be

retrieved from the ducts, biopsies can be performed, strictures can be

dilated and/or stented (Fig. 322-18), and ductal leaks can be treated

(Fig. 322-19). ERCP is usually performed for therapy but is also

important diagnostically as it facilitates tissue sampling of biliary or

pancreatic ductal strictures.

■ ENDOSCOPIC ULTRASOUND

Endoscopic ultrasound (EUS) utilizes ultrasound transducers incorporated into the tip of a flexible endoscope. Ultrasound images are

obtained of the gut wall and adjacent organs, vessels, lymph nodes, and

other structures. High-resolution images are obtained by bringing a

high-frequency ultrasound transducer close to the area of interest via

endoscopy. EUS provides the most accurate preoperative local staging

2392 PART 10 Disorders of the Gastrointestinal System

C D

A B

FIGURE 322-10 Colonic polyps. A. Pedunculated polyp on a stalk. B. Sessile polyp.

A B

FIGURE 322-9 Causes of colitis. A. Chronic ulcerative colitis with diffuse ulcerations and exudates. B. Severe Crohn’s colitis with deep ulcers. C. Pseudomembranous colitis

with yellow, adherent pseudomembranes. D. Ischemic colitis with patchy mucosal edema, subepithelial hemorrhage, superficial ulcerations, and cyanosis.

2393 Gastrointestinal Endoscopy CHAPTER 322

FIGURE 322-12 Flat serrated polyp in the cecum. A. Appearance of the lesion under

conventional white-light imaging. B. Mucosal patterns and boundary of the lesion

enhanced with narrow-band imaging. C. Submucosal lifting of the lesion with dye

(methylene blue) injection prior to resection.

FIGURE 322-13 Capsule endoscopy. Image of a jejunal vascular ectasia.

FIGURE 322-14 Double-balloon enteroscopy. Radiograph of the orally inserted

instrument deep in the small intestine.

FIGURE 322-11 Ulcerated colon adenocarcinoma narrowing the colonic lumen.

A

B

C

of esophageal, pancreatic, and rectal malignancies (Fig. 322-20), but

it does not detect most distant metastases. EUS is also useful for diagnosis of bile duct stones, gallbladder disease, subepithelial gastrointestinal lesions, and chronic pancreatitis. Fine-needle aspirates and core

biopsies of organs, masses, and lymph nodes in the posterior mediastinum, abdomen, retroperitoneum, and pelvis can be obtained under

EUS guidance (Fig. 322-21). EUS-guided therapeutic procedures are

increasingly performed, including drainage of abscesses, pseudocysts,

and pancreatic necrosis into the gut lumen (Video V5-2); celiac plexus

neurolysis for treatment of pancreatic pain; ethanol ablation of pancreatic neuroendocrine tumors; treatment of gastrointestinal hemorrhage;

and drainage of obstructed biliary and pancreatic ducts.

■ NATURAL ORIFICE TRANSLUMINAL

ENDOSCOPIC SURGERY

Natural orifice transluminal endoscopic surgery (NOTES) is an

evolving collection of endoscopic methods that entail passage of an

2394 PART 10 Disorders of the Gastrointestinal System

FIGURE 322-15 Nonsteroidal anti-inflammatory drug (NSAID)–induced proximal

ileal stricture managed via double-balloon enteroscopy. A. High-grade ileal

stricture causing obstructive symptoms. B. Balloon dilation of the ileal stricture.

C. Appearance of the stricture after dilation.

A

B

C

A

B

FIGURE 322-16 Endoscopic retrograde cholangiopancreatography (ERCP) for bile

duct stones with cholangitis. A. Faceted bile duct stones are demonstrated in the

common bile duct. B. After endoscopic sphincterotomy, the stones are extracted

with a Dormia basket. A small abscess communicates with the left hepatic duct.

2395 Gastrointestinal Endoscopy CHAPTER 322

FIGURE 322-17 Endoscopic sphincterotomy. A. A normal-appearing ampulla of Vater. B. Sphincterotomy is performed with electrosurgery. C. Bile duct stones are extracted

with a balloon catheter. D. Final appearance of the sphincterotomy.

FIGURE 322-18 Endoscopic diagnosis, staging, and palliation of hilar cholangiocarcinoma. A. Endoscopic retrograde cholangiopancreatography (ERCP) in a patient with

obstructive jaundice demonstrates a malignant-appearing stricture of the biliary confluence extending into the left and right intrahepatic ducts. B. Intraductal ultrasound

of the biliary stricture demonstrates marked bile duct wall thickening due to tumor (T) with partial encasement of the hepatic artery (arrow). C. Intraductal biopsy obtained

during ERCP demonstrates malignant cells infiltrating the submucosa of the bile duct wall (arrow). D. Endoscopic placement of bilateral self-expanding metal stents (arrow)

relieves the biliary obstruction. GB, gallbladder. (Image courtesy of Dr. Thomas Smyrk.)

A B C D

2396 PART 10 Disorders of the Gastrointestinal System

FIGURE 322-19 Bile leak (arrow) from a duct of Luschka after laparoscopic

cholecystectomy. Contrast leaks from a small right intrahepatic duct into the

gallbladder fossa, then flows into the pigtail of a percutaneous drainage catheter.

A B C

FIGURE 322-20 Local staging of gastrointestinal cancers with endoscopic ultrasound. In each example, the white arrowhead marks the primary tumor and the black arrow

indicates the muscularis propria (mp) of the intestinal wall. A. T1 gastric cancer. The tumor does not invade the mp. B. T2 esophageal cancer. The tumor invades the mp.

C. T3 esophageal cancer. The tumor extends through the mp into the surrounding tissue and focally abuts the aorta (AO).

endoscope or its accessories into or through the wall of the gastrointestinal tract to perform diagnostic or therapeutic interventions.

Some NOTES procedures, such as percutaneous endoscopic gastrostomy (PEG) or endoscopic necrosectomy of pancreatic necrosis,

are well-established clinical procedures (Video V5-2); others such as

peroral endoscopic myotomy (POEM) for achalasia (Fig. 322-22) and

gastroparesis, peroral endoscopic tumorectomy (POET) (Fig. 322-23),

and endoscopic full-thickness resection (EFTR) of gastrointestinal

mural lesions (Fig. 322-24, Video V5-3), are emerging as minimally

invasive therapeutic options. NOTES is an area of continuing innovation and endoscopic research.

■ ENDOSCOPIC RESECTION AND CLOSURE

TECHNIQUES

Endoscopic mucosal resection (EMR) (Fig. 322-25, Video V5-4) and

endoscopic submucosal dissection (ESD) (Fig. 322-26, Video V5-5)

are the two commonly used techniques for the resection of benign

and early-stage malignant gastrointestinal neoplasms. In addition to

providing larger specimens for more accurate histopathologic assessment and diagnosis, these techniques can be potentially curative for

some dysplastic lesions and focal intramucosal carcinomas involving

the esophagus, stomach, and colon. Several devices are available for

closure of EMR and ESD defects, as well as gastrointestinal fistulas and

perforations. Endoscopic clips deployed through the working channel of an endoscope have been used for many years to treat bleeding

lesions, and the development of larger over-the-scope clips has facilitated endoscopic closure of gastrointestinal fistulas and perforations

not previously amenable to endoscopic therapy (Video V5-6). Endoscopic suturing can be used to close some perforations and large

defects (Fig. 322-27), anastomotic leaks, and fistulas. Other potential

indications for endoscopic suturing include stent fixation to prevent

migration (Fig. 322-28, Video V5-7) and endoscopic bariatric procedures. These technologies are playing an expanding role in patient care.

RISKS OF ENDOSCOPY

Medications used during moderate sedation may cause respiratory

depression or allergic reactions. All endoscopic procedures carry some

risk of bleeding and gastrointestinal perforation. The risk is small with

diagnostic upper endoscopy, flexible sigmoidoscopy, and colonoscopy

(<1:1000 procedures), but it ranges from 0.5 to 5% when therapeutic

procedures such as polypectomy, EMR, ESD, control of hemorrhage,

or stricture dilation are performed. The risk of adverse events for diagnostic EUS (without needle aspiration) is similar to that for diagnostic

upper endoscopy.

Infectious complications are uncommon with most endoscopic procedures. Some procedures carry a higher incidence of postprocedure

bacteremia, and prophylactic antibiotics may be indicated (Table 322-1).

Management of antithrombotic agents prior to endoscopic procedures

should take into account the procedural risk of hemorrhage, the agent,

and the patient condition, as summarized in Table 322-2.

ERCP carries additional risks. Pancreatitis occurs in ~5% of patients

undergoing the procedure, and young, anicteric patients with normal

ducts are at increased risk (up to 25%). Post-ERCP pancreatitis is

usually mild and self-limited, but it may result in prolonged hospitalization, surgery, diabetes, or death when severe. Significant bleeding

occurs after endoscopic sphincterotomy in ~1% of cases. Ascending

cholangitis, pseudocyst infection, duodenal perforation, and abscess

formation may occur as a result of ERCP.

Percutaneous gastrostomy tube placement during EGD is associated

with a 10–15% incidence of adverse events, most often wound infections. Fasciitis, pneumonia, bleeding (Fig. 322-29), buried bumper

syndrome (Fig. 322-30), and colonic injury may result from gastrostomy tube placement.

URGENT ENDOSCOPY

■ ACUTE GASTROINTESTINAL HEMORRHAGE

Endoscopy is the primary diagnostic and therapeutic technique for

patients with acute gastrointestinal hemorrhage. Although gastrointestinal bleeding stops spontaneously in most cases, some patients will

2397 Gastrointestinal Endoscopy CHAPTER 322

A B

FIGURE 322-21 Endoscopic ultrasound (EUS)–guided fine-needle aspiration (FNA). A. Ultrasound image of a 22-gauge needle passed through the duodenal wall and

positioned in a hypoechoic pancreatic head mass. B. Micrograph of aspirated malignant cells. (Image courtesy of Dr. Michael R. Henry.)

FIGURE 322-22 Peroral endoscopic myotomy (POEM) for achalasia. A. Dilated aperistaltic esophagus with retained secretions. B. Hypertonic lower esophageal sphincter

(LES) region. C. Mucosal incision (mucosotomy) 10 cm proximal to the LES. D. Submucosal dissection using an electrosurgical knife following endoscope entry through the

mucosotomy site into the submucosal space. E. Completion of submucosal tunnel to the cardia. F. Initiation of myotomy of the muscularis propria distal to the mucosotomy

site. G. Completion of myotomy to the cardia. H. Closure of mucosotomy site with clips. I. Patulous gastroesophageal junction following myotomy.

A B C

D E F

G H I

2398 PART 10 Disorders of the Gastrointestinal System

C D

A B

E F

G H

FIGURE 322-23 Peroral endoscopic tumorectomy (POET). A. Mid-esophageal subepithelial lesion (arrow). B. Mucosal incision (mucosotomy) 5 cm proximal to the

lesion. C. Submucosal dissection and tunneling to the site of the lesion. D. Dissection of the lesion from its attachment to the muscularis propria. E. Postresection defect

through the muscularis propria. F. Mucosotomy site. G. Closure of mucosotomy site with clips. H. Resected specimen (leiomyoma).

2399 Gastrointestinal Endoscopy CHAPTER 322

A B

C D

FIGURE 322-24 Endoscopic full-thickness resection (EFTR) of a gastrointestinal stromal tumor. A. Subepithelial lesion in the proximal stomach. B. Hypoechoic lesion arising

from the fourth layer (muscularis propria) at endoscopic ultrasound. C. Full-thickness resection defect. D. Closure of defect using an over-the-scope clip.

FIGURE 322-25 Endoscopic mucosal resection (EMR). A. Large sessile polypoid fold in the transverse colon. B. Lifting of lesion following submucosal fluid injection.

C. Piecemeal hot snare resection. D. Initial resection site. E. Resection defect following completion of piecemeal EMR.

A B

have persistent or recurrent hemorrhage that may be life-threatening.

Clinical predictors of rebleeding help identify patients most likely

to benefit from urgent endoscopy and endoscopic, angiographic, or

surgical hemostasis.

Initial Evaluation The initial evaluation of the bleeding patient

focuses on the severity of hemorrhage as reflected by the presence of

supine hypotension or tachycardia, postural vital sign changes, and

the frequency of hematemesis or melena. Decreases in hematocrit and

hemoglobin lag behind the clinical course and are not reliable gauges

of the magnitude of acute bleeding. Nasogastric tube aspiration and

lavage can also be used to judge the severity of bleeding, but these are

no longer routinely performed for this purpose. The bedside initial

evaluation, completed well before the bleeding source is confidently

identified, guides immediate supportive care of the patient, triage to

the ward or intensive care unit, and timing of endoscopy. The severity

of the initial hemorrhage is the most important indication for urgent

endoscopy, since a large initial bleed increases the likelihood of ongoing or recurrent bleeding. Patients with resting hypotension or orthostatic change in vital signs, repeated hematemesis, or bloody nasogastric

2400 PART 10 Disorders of the Gastrointestinal System

E

C D

A B

FIGURE 322-26 Endoscopic submucosal dissection (ESD). A. Large, flat, distal rectal adenoma. B. Circumferential incision following submucosal fluid injection at the

periphery of the lesion. C. ESD using an electrosurgical knife. D. Rectal defect following ESD. E. Specimen resected en bloc.

FIGURE 322-25 (Continued)

2401 Gastrointestinal Endoscopy CHAPTER 322

C D

E

A B

FIGURE 322-27 Closure of large defect using an endoscopic suturing device. A. Ulcerated inflammatory fibroid polyp in the antrum. B. Large defect following endoscopic

submucosal dissection of the lesion. C. Closure of the defect using endoscopic sutures (arrows). D. Resected specimen.

FIGURE 322-26 (Continued)

2402 PART 10 Disorders of the Gastrointestinal System

C D

A B

C D

FIGURE 322-28 Prevention of stent migration using endoscopic sutures. A. Esophagogastric anastomotic stricture refractory to balloon dilation. B. Temporary placement of

a covered esophageal stent. C. Endoscopic suturing device to anchor the stent to the esophageal wall. D. Stent fixation with endoscopic sutures (arrows).

aspirate that does not clear with large-volume lavage or those requiring

blood transfusions should be considered for urgent endoscopy. In

addition, patients with cirrhosis, coagulopathy, or respiratory or renal

failure and those >70 years old are more likely to have significant

rebleeding and to benefit from prompt evaluation and treatment.

Bedside evaluation also suggests an upper or lower gastrointestinal

source of bleeding in most patients. Over 90% of patients with melena

are bleeding proximal to the ligament of Treitz, and ~85% of patients

with hematochezia are bleeding from the colon. Melena can result from

bleeding in the small bowel or right colon, especially in older patients

with slow colonic transit. Conversely, some patients with massive

hematochezia may be bleeding from an upper gastrointestinal source,

with rapid intestinal transit. Early upper endoscopy should be considered in such patients.

Endoscopy should be performed after the patient has been resuscitated with intravenous fluids and transfusions, as necessary. Marked

coagulopathy or thrombocytopenia is usually treated before endoscopy, since correction of these abnormalities may lead to resolution of

bleeding, and techniques for endoscopic hemostasis are limited in such

patients. Metabolic derangements should also be addressed. Tracheal

intubation for airway protection should be considered before upper

endoscopy in patients with repeated recent hematemesis, particularly in

those with suspected variceal hemorrhage. A single dose of erythromycin (3–4 mg/kg or 250 mg) administered intravenously 30–90 min prior

FIGURE 322-27 (Continued)

2403 Gastrointestinal Endoscopy CHAPTER 322

TABLE 322-1 Antibiotic Prophylaxis for Endoscopic Procedures

PATIENT CONDITION PROCEDURE CONTEMPLATED GOAL OF PROPHYLAXIS

PERIPROCEDURAL ANTIBIOTIC

PROPHYLAXIS

All cardiac conditions Any endoscopic procedure Prevention of infective endocarditis Not indicated

Bile duct obstruction in the absence of

cholangitis

ERCP with complete drainage Prevention of cholangitis Not recommended

Bile duct obstruction in the absence of

cholangitis

ERCP with anticipated incomplete

drainage (e.g., sclerosing cholangitis,

hilar strictures)

Prevention of cholangitis Recommended; continue antibiotics

after the procedure

Sterile pancreatic fluid collection

(e.g., pseudocyst, necrosis), which

communicates with pancreatic duct

ERCP Prevention of cyst infection Recommended; continue antibiotics

after the procedure

Sterile pancreatic fluid collection Transmural drainage Prevention of cyst infection Recommended

Solid lesion along upper GI tract EUS-FNA Prevention of local infection Not recommendeda

Solid lesion along lower GI tract EUS-FNA Prevention of local infection Not recommendeda

Cystic lesions along GI tract (including

mediastinum and pancreas)

EUS-FNA Prevention of cyst infection Recommended

All patients Percutaneous endoscopic feeding tube

placement

Prevention of peristomal infection Recommendedb

Cirrhosis with acute GI bleeding Required for all such patients,

regardless of endoscopic procedures

Prevention of infectious complications

and reduction of mortality

Recommended, upon admissionc

Continuous peritoneal dialysis Lower GI tract endoscopy Prevention of bacterial peritonitis Recommended

Synthetic vascular graft and other

nonvalvular cardiovascular devices

Any endoscopic procedure Prevention of graft and device infection Not recommendedd

Prosthetic joints Any endoscopic procedure Prevention of septic arthritis Not recommendedd

a

Low rates of bacteremia and local infection. b

Cefazolin or an antibiotic with equivalent coverage of oral and skin flora. c

Risk for bacterial infection associated with cirrhosis

and GI bleeding is well established; ceftriaxone or a quinolone antibiotic recommended. d

Very low risk of infection.

Abbreviations: ERCP, endoscopic retrograde cholangiopancreatography; EUS-FNA, endoscopic ultrasound–fine-needle aspiration; GI, gastrointestinal.

Source: Reproduced with permission from MA Kashab et al: Antibiotic prophylaxis for GI endoscopy. Gastrointest Endosc 81:81, 2015.

to upper endoscopy increases gastric emptying and may clear blood and

clots from the stomach to improve endoscopic visualization.

Most patients with hematochezia who are otherwise stable can

undergo semielective colonoscopy. Controlled trials have not shown a

benefit to urgent colonoscopy in patients hospitalized with hematochezia, although selected patients with massive or recurrent large-volume

episodes of hematochezia should probably undergo urgent colonoscopy

after a rapid colonic purge with an oral polyethylene glycol solution.

Colonoscopy has a higher diagnostic yield than radionuclide bleeding

scans or angiography in lower gastrointestinal bleeding, and endoscopic therapy can be applied in some cases. Urgent colonoscopy can

be hindered by poor visualization due to persistent vigorous bleeding

with recurrent hemodynamic instability, and other techniques (such as

angiography or even emergent subtotal colectomy) must be employed.

In such patients, massive bleeding originating from an upper gastrointestinal source should also be considered and excluded promptly by

upper endoscopy. The anal and rectal mucosa should also be visualized endoscopically early in the course of massive rectal bleeding, as

bleeding lesions in or close to the anal canal may be identified that are

amenable to endoscopic or surgical transanal hemostatic techniques.

Peptic Ulcer The endoscopic appearance of peptic ulcers provides

useful prognostic information and guides the need for endoscopic

therapy in patients with acute hemorrhage (Fig. 322-31). A cleanbased ulcer is associated with a low risk (3–5%) of rebleeding; patients

with melena and a clean-based ulcer may be discharged home from

the emergency room or endoscopy suite if they are young, reliable,

otherwise healthy, and able to return as needed. Flat pigmented spots

and adherent clots covering the ulcer base have a 10% and 20% risk

of rebleeding, respectively. Flat pigmented spots do not require treatment, but endoscopic therapy is generally applied to an ulcer with an

adherent clot. When a fibrin plug is seen protruding from a vessel wall

in the base of an ulcer (so-called sentinel clot or visible vessel), the risk

of rebleeding from the ulcer approximates 40%. This finding typically

leads to endoscopic therapy to decrease the rebleeding rate. When

active spurting from an ulcer is seen, there is a 90% risk of ongoing

bleeding without endoscopic or surgical therapy.

Endoscopic therapy of ulcers with high-risk stigmata typically lowers the rebleeding rate to 5–10%. Several hemostatic techniques are

available, including injection of epinephrine or a sclerosant into and

around the vessel (Fig. 322-32), “coaptive coagulation” of the vessel in

the base of the ulcer using a thermal probe that is pressed against the

site of bleeding (Fig. 322-33), placement of through-the-scope clips

(Fig. 322-34) or an over-the-scope clip (Fig. 322-35), or a combination

of these modalities (Video V5-8). Epinephrine injection can slow or

stop active bleeding, but it is not enough as a stand-alone technique

for definitive hemostasis. In conjunction with endoscopic therapy,

the administration of a proton pump inhibitor decreases the risk of

rebleeding and improves patient outcome.

Varices Two complementary strategies guide therapy of bleeding

varices: local treatment of the bleeding varices and treatment of the

underlying portal hypertension. Local therapies, including endoscopic

variceal band ligation, endoscopic variceal sclerotherapy, stent placement, and balloon tamponade with a Sengstaken-Blakemore tube,

effectively control acute hemorrhage in most patients, although therapies that decrease portal pressure (pharmacologic treatment, surgical

shunts, or radiologically placed intrahepatic portosystemic shunts) also

play an important role.

Endoscopic variceal ligation (EVL) is indicated for the prevention

of a first bleed (primary prophylaxis) from large esophageal varices

(Fig. 322-36), particularly in patients in whom nonselective beta

blockers are contraindicated or not tolerated. EVL is also the preferred

endoscopic therapy for control of active esophageal variceal bleeding

and for subsequent eradication of esophageal varices (secondary prophylaxis). During EVL, a varix is suctioned into a cap fitted on the end

of the endoscope, and a rubber band is released from the cap, ligating

the varix (Fig. 322-37, Video V5-9). EVL controls acute hemorrhage

2404 PART 10 Disorders of the Gastrointestinal System

TABLE 322-2 Management of Antithrombotic Drugs Prior to Endoscopic Procedures

DRUG

BLEEDING RISK

OF PROCEDURE MANAGEMENT

INTERVAL BETWEEN

LAST DOSE AND

PROCEDURE COMMENTS

Warfarin Lowa Continue N/A Ensure that INR is not supratherapeutic

Highb Discontinue 3–7 days (usually 5),

INR should be ≤1.5 for

procedure

Consider bridging therapy with heparinc

; usually safe to

resume warfarin on the same or next day

For life-threatening GI hemorrhage, consider reversal with

unactivated prothrombin complex concentrate

Dabigatran, rivaroxaban,

apixaban, edoxaban

Lowa Continue or hold

morning dose on day of

procedure

N/A

Dabigatran Highb Discontinue 2–3 days if GFR is

≥50 mL/min, 3–4 days if

GFR is 30–49 mL/min

Bridging therapy not recommended; resume drug when

bleeding risk is low

For life-threatening GI hemorrhage, consider use of a

reversal agent

Rivaroxaban, apixaban,

edoxaban

Higha Discontinue 2 days if GFR is

≥60 mL/min, 3 days if GFR

is 30–59 mL/min, 4 days if

GFR is <30 mL/min

Bridging therapy not recommended; resume drug when

bleeding risk is low

For life-threatening GI hemorrhage, consider use of a

reversal agent

Heparin Lowa Continue N/A

Highb Discontinue 4–6 h for unfractionated

heparin

Skip one dose if using low-molecular-weight heparin

Aspirin Any Continue N/A Low-dose aspirin does not substantially increase the risk of

endoscopic procedures

Aspirin with dipyridamole Lowa Continue N/A

Highb Discontinue 2–7 days Consider continuing aspirin monotherapy

P2Y12 receptor antagonists

(clopidogrel, prasugrel,

ticlopidine, ticagrelor,

cangrelor)

Lowa Continue N/A

Highb Coronary stent in place:

discuss with cardiologist

5 days (clopidogrel

or ticagrelor), 7 days

(prasugrel), 10–14 days

(ticlopidine)

Risk of stent thrombosis for at least 12 months after

insertion of drug-eluting coronary stent or 1 month after

insertion of bare metal coronary stent

No coronary stent:

discontinue, consider

substituting aspirin

a

Low-risk endoscopic procedures include esophagogastroduodenoscopy (EGD) or colonoscopy with or without biopsy, endoscopic ultrasound (EUS) without fine-needle

aspiration (FNA), and endoscopic retrograde cholangiopancreatography (ERCP) with stent exchange. b

High-risk endoscopic procedures include EGD or colonoscopy with

dilation, polypectomy, or thermal ablation; percutaneous endoscopic gastrostomy (PEG); EUS with FNA; and ERCP with sphincterotomy or pseudocyst drainage. c

Bridging

therapy with low-molecular-weight heparin should be considered for patients discontinuing warfarin who are at high risk for thromboembolism, including those with (1)

atrial fibrillation with a CHA2

DS2

-VASc score ≥3, mechanical valve(s), or history of stroke or transient ischemic attack; (2) mechanical mitral valve; (3) mechanical aortic

valve with other thromboembolic risk factors or older-generation mechanical aortic valve; or (4) venous thromboembolism within the past 3 months.

Abbreviations: GFR, glomerular filtration rate; INR, international normalized ratio; N/A, not applicable.

Source: Adapted from RD Acosta et al: Gastrointest Endosc 83:3, 2016; and AM Veitch et al: Gut 65:374, 2016.

A B

FIGURE 322-29 Bleeding from percutaneous endoscopic gastrostomy (PEG) tube placement. A. Patient with melena from a recently placed PEG tube. B. Loosening of the

internal disk bumper of the PEG tube revealed active bleeding from within the PEG tract.

2405 Gastrointestinal Endoscopy CHAPTER 322

A B

FIGURE 322-30 Buried bumper syndrome. A. Migration of the internal disk bumper of a percutaneous endoscopic gastrostomy (PEG) tube through the gastric wall.

B. Close-up view of the disk bumper (arrow) buried in the gastric wall.

A B

FIGURE 322-31 Stigmata of hemorrhage in peptic ulcers. A. Gastric antral ulcer with a clean base. B. Duodenal ulcer with flat pigmented spots (arrows). C. Duodenal ulcer

with a dense adherent clot. D. Duodenal ulcer with a pigmented protuberance/visible vessel. E. Duodenal ulcer with active spurting (arrow).

in up to 90% of patients. Complications of EVL, such as postligation

ulcer bleeding and esophageal stenosis, are uncommon. Endoscopic

variceal sclerotherapy (EVS) involves the injection of a sclerosing,

thrombogenic solution into or next to esophageal varices. EVS also

controls acute hemorrhage in most patients, but it is generally used as

salvage therapy when band ligation fails because of its higher complication rate. Bleeding from large gastric fundal varices (Fig. 322-38) is

best treated with endoscopic cyanoacrylate (“glue”) injection (Video

V5-10), since EVL or EVS of these varices is associated with a high

rebleeding rate. Complications of cyanoacrylate injection include

infection and glue embolization to other organs, such as the lungs,

brain, and spleen.

After treatment of the acute hemorrhage, an elective course of

endoscopic therapy can be undertaken with the goal of eradicating

esophageal varices and preventing rebleeding months to years later.

However, this chronic therapy is less successful, preventing long-term

rebleeding in ~50% of patients. Pharmacologic therapies that decrease

portal pressure have similar efficacy. The preferred strategy, however,

for secondary prophylaxis of variceal bleeding is the combination of

EVL with a nonselective beta blocker.

Dieulafoy’s Lesion This lesion, also called persistent caliber

artery, is a large-caliber arteriole that runs immediately beneath the

gastrointestinal mucosa and bleeds through a focal mucosal erosion

(Fig. 322-39). Dieulafoy’s lesion commonly involves the lesser curvature of the proximal stomach, causes impressive arterial hemorrhage,

and may be difficult to diagnose when not actively bleeding; it is often

recognized only after repeated endoscopy for recurrent bleeding.

Endoscopic therapy, such as thermal coagulation, band ligation, clip

placement, or endoscopic suturing, is typically effective for control

of bleeding and sealing of the underlying vessel once the lesion has

been identified (Video V5-11). Rescue therapies, such as angiographic

embolization or surgical oversewing, are considered in situations

where endoscopic therapy has failed.

2406 PART 10 Disorders of the Gastrointestinal System

E

C D

FIGURE 322-32 Injection therapy for ulcer hemostasis. Epinephrine injection into a

duodenal ulcer with visible vessel (arrow) and adherent clot.

Mallory-Weiss Tear A Mallory-Weiss tear is a linear mucosal rent

near or across the gastroesophageal junction that is often associated

with retching or vomiting (Fig. 322-40). When the tear disrupts a

submucosal arteriole, brisk hemorrhage may result. Endoscopy is the

best method for diagnosis, and an actively bleeding tear can be treated

endoscopically with coaptive coagulation, band ligation, or hemoclips,

with or without epinephrine injection (Video V5-12). Unlike peptic

ulcer, a Mallory-Weiss tear with a nonbleeding sentinel clot in its base

rarely rebleeds and thus does not necessitate endoscopic therapy.

Vascular Ectasias Vascular ectasias are flat mucosal vascular

anomalies that are best diagnosed by endoscopy. They usually cause

slow intestinal blood loss and occur either in a sporadic fashion or in a

well-defined pattern of distribution (e.g., gastric antral vascular ectasia

[GAVE] or “watermelon stomach”) (Fig. 322-41). Cecal vascular ectasias, GAVE, and radiation-induced rectal ectasias are often responsive

to local endoscopic ablative therapy, such as argon plasma coagulation

(Video V5-13). Patients with diffuse small-bowel vascular ectasias

(associated with chronic renal failure and with hereditary hemorrhagic

telangiectasia) may continue to bleed despite endoscopic treatment of

easily accessible lesions by conventional endoscopy. These patients may

benefit from device-assisted enteroscopy with endoscopic hemostasis

or pharmacologic therapy, such as octreotide or low-dose thalidomide,

in those who continue to bleed despite endoscopic therapy.

FIGURE 322-31 (Continued)

2407 Gastrointestinal Endoscopy CHAPTER 322

A B

C

FIGURE 322-33 Contact coagulation for ulcer hemostasis. A. Duodenal ulcer with a visible vessel (arrow). B. Coagulation of the vessel with a contact thermal probe.

C. Obliteration of the treated vessel (arrow).

A B

FIGURE 322-34 Through-the-scope clip placement for ulcer hemostasis. A. Superficial duodenal ulcer with visible vessel (arrow). B. Hemostasis secured following

placement of multiple through-the-scope clips.

2408 PART 10 Disorders of the Gastrointestinal System

A

B

FIGURE 322-35 Over-the-scope clip placement for ulcer hemostasis. A. Pyloric

channel ulcer with visible vessel (arrow). B. Hemostasis secured following

placement of an over-the-scope clip.

FIGURE 322-36 Esophageal varices.

A

B

FIGURE 322-37 Endoscopic variceal ligation. A. Esophageal varices with red wale

marks. B. Band ligation of varices.

Colonic Diverticula Diverticula form where nutrient arteries

penetrate the muscular wall of the colon en route to the colonic mucosa

(Fig. 322-42). The artery found in the base of a diverticulum may

bleed, causing painless and impressive hematochezia. Colonoscopy

is indicated in patients with hematochezia and suspected diverticular

hemorrhage, since other causes of bleeding (such as vascular ectasias,

colitis, and colon cancer) must be excluded. In addition, an actively

bleeding diverticulum may be seen and treated during colonoscopy

(Fig. 322-43, Video V5-14).

■ GASTROINTESTINAL OBSTRUCTION AND

PSEUDOOBSTRUCTION

Endoscopy is useful for evaluation and treatment of some forms of

gastrointestinal obstruction. An important exception is small-bowel

obstruction due to surgical adhesions, which is generally not diagnosed

or treated endoscopically. Esophageal, gastroduodenal, and colonic

obstruction or pseudoobstruction can all be diagnosed and often managed endoscopically.

Acute Esophageal Obstruction Esophageal obstruction by

impacted food (Fig. 322-44) or an ingested foreign body (Fig. 322-45)

is a potentially life-threatening event and represents an endoscopic

emergency. Left untreated, the patient may develop esophageal ulceration, ischemia, and perforation. Patients with persistent esophageal

obstruction often have hypersalivation and are usually unable to

swallow water. Sips of a carbonated beverage, sublingual nifedipine

or nitrates, or intravenous glucagon may resolve an esophageal food

impaction, but in many patients, an underlying web, ring, or stricture is

present, and endoscopic removal of the obstructing food bolus is necessary. Endoscopy is generally the best initial test in such patients since

endoscopic removal of the obstructing material is usually possible, and

the presence of an underlying esophageal pathology can often be determined. Radiographs of the chest and neck should be considered before

endoscopy in patients with fever, obstruction for ≥24 h, or ingestion of

a sharp object, such as a fishbone. Radiographic contrast studies interfere with subsequent endoscopy and are not advisable in most patients

with a clinical picture of esophageal obstruction.

2409 Gastrointestinal Endoscopy CHAPTER 322

A B

FIGURE 322-38 Gastric varices. A. Large gastric fundal varices. B. Stigmata of recent bleeding from the same gastric varices (arrow).

A B

C D

FIGURE 322-39 Dieulafoy’s lesion. A. Actively spurting gastric Dieulafoy’s lesion. B. Coagulation of the lesion using a contact thermal probe. C. Hemostasis secured

following contact coagulation (arrow). D. Histology of a gastric Dieulafoy’s lesion. A persistent caliber artery (arrows) is present in the gastric submucosa, immediately

beneath the mucosa.

2410 PART 10 Disorders of the Gastrointestinal System

FIGURE 322-40 Mallory-Weiss tear at the gastroesophageal junction.

Gastric Outlet Obstruction Obstruction of the gastric outlet is

commonly caused by gastric, duodenal, or pancreatic malignancy or

chronic peptic ulceration with stenosis of the pylorus (Fig. 322-46).

Patients vomit partially digested food many hours after eating. Gastric decompression with a nasogastric tube and subsequent lavage for

removal of retained material is the first step in treatment. Endoscopy is

useful for diagnosis and treatment. Patients with benign pyloric stenosis may be treated with endoscopic balloon dilation of the pylorus, and

a course of endoscopic dilation results in long-term relief of symptoms

in ~50% of patients. Removable, fully covered lumen-apposing metal

stents (LAMS) may also be used to treat benign pyloric stenosis (Video

V5-15). Malignant gastric outlet obstruction can be relieved with

endoscopically placed expandable stents in patients with inoperable

malignancy (Video V5-16).

Colonic Obstruction and Pseudoobstruction These conditions both present with abdominal distention and discomfort,

tympany, and a dilated colon on plain abdominal radiography. The

radiographic appearance may be characteristic of a particular condition, such as sigmoid volvulus (Fig. 322-47). Both obstruction and

pseudoobstruction may lead to colonic perforation if left untreated.

Acute colonic pseudoobstruction is a form of colonic ileus that is

usually attributable to electrolyte disorders, narcotic and anticholinergic medications, immobility (as after surgery), or retroperitoneal

hemorrhage or mass. Multiple causative factors are often present.

Colonoscopy, water-soluble contrast enema, or CT may be used to

assess for an obstructing lesion and differentiate obstruction from

pseudoobstruction. One of these diagnostic studies should be strongly

considered if the patient does not have clear risk factors for pseudoobstruction, if radiographs do not show air in the rectum, or if the

patient fails to improve when underlying causes of pseudoobstruction

have been addressed. The risk of cecal perforation in pseudoobstruction rises when the cecal diameter exceeds 12 cm, and decompression of the colon may be achieved using intravenous neostigmine or

via colonoscopic decompression (Fig. 322-48). Most patients should

receive a trial of conservative therapy (with correction of electrolyte

disorders, removal of offending medications, and increased mobilization) before undergoing an invasive decompressive procedure for

colonic pseudoobstruction.

Colonic obstruction is an indication for urgent intervention. In

the past, emergent diverting colostomy was usually performed with

a subsequent second operation after bowel preparation to treat the

underlying cause of obstruction. Colonoscopic placement of an

expandable stent is an alternative treatment option that can relieve

malignant colonic obstruction without emergency surgery and permit

bowel preparation for an elective one-stage operation (Fig. 322-49,

Video V5-17).

■ ACUTE BILIARY OBSTRUCTION

The steady, severe pain that occurs when a gallstone acutely obstructs the

common bile duct often brings patients to a hospital. The diagnosis of a

ductal stone is suspected when the patient is jaundiced or when serum

liver tests or pancreatic enzyme levels are elevated; it is confirmed by

EUS, magnetic resonance cholangiopancreatography (MRCP), or direct

cholangiography (performed endoscopically, percutaneously, or during

surgery). ERCP is the primary means of treating common bile duct

stones (Figs. 322-16 and 322-17), although they can also be removed by

bile duct exploration at the time of cholecystectomy. Radiologic percutaneous biliary drainage may be required in some cases.

Bile Duct Imaging While transabdominal ultrasound diagnoses

only a minority of bile duct stones, MRCP and EUS are >90% accurate

and have an important role in diagnosis. Examples of these modalities

are shown in Fig. 322-50.

If the suspicion for a bile duct stone is high and urgent treatment is

required (as in a patient with obstructive jaundice and biliary sepsis),

ERCP is the procedure of choice since it remains the gold standard

for diagnosis and allows for immediate treatment (Video V5-18). If a

persistent bile duct stone is relatively unlikely (as in a patient with gallstone pancreatitis), ERCP may be supplanted by less invasive imaging

techniques, such as EUS, MRCP, or intraoperative cholangiography

performed during cholecystectomy, sparing some patients the risk and

discomfort of ERCP.

Ascending Cholangitis Charcot’s triad of jaundice, abdominal

pain, and fever is present in ~70% of patients with ascending cholangitis and biliary sepsis. These patients are managed initially with fluid

resuscitation and intravenous antibiotics. Abdominal ultrasound is

often performed to assess for gallbladder stones and bile duct dilation. However, the bile duct may not be dilated early in the course of

acute biliary obstruction. Medical management usually improves the

patient’s clinical status, providing a window of ~24 h during which

biliary drainage should be established, typically by ERCP. Undue delay

can result in recrudescence of overt sepsis and increased morbidity and

mortality rates. In addition to Charcot’s triad, the additional presence

of shock and confusion (Reynolds’s pentad) is associated with a high

mortality rate and should prompt urgent intervention to restore biliary

drainage.

Gallstone Pancreatitis Gallstones may cause acute pancreatitis

as they pass through the ampulla of Vater. The occurrence of gallstone

pancreatitis usually implies passage of a stone into the duodenum, and

only ~20% of patients harbor a persistent stone in the ampulla or the

common bile duct. Retained stones are more common in patients with

jaundice, rising serum liver tests following hospitalization, severe pancreatitis, or superimposed ascending cholangitis.

Urgent ERCP decreases the morbidity rate of gallstone pancreatitis in a subset of patients with retained bile duct stones. It is unclear

whether the benefit of ERCP is mainly attributable to treatment and

prevention of ascending cholangitis or to relief of pancreatic ductal

obstruction. ERCP is warranted early in the course of gallstone pancreatitis if ascending cholangitis is suspected, especially in a jaundiced

patient. Urgent ERCP may also benefit patients predicted to have

severe pancreatitis using a clinical index of severity, such as the Glasgow or Ranson score. Since the benefit of ERCP is limited to patients

with a retained bile duct stone, a strategy of initial MRCP or EUS for

diagnosis decreases the utilization of ERCP in gallstone pancreatitis

and improves clinical outcomes by limiting the occurrence of ERCP-related adverse events.

ELECTIVE ENDOSCOPY

■ DYSPEPSIA

Dyspepsia is a chronic or recurrent burning discomfort or pain in

the upper abdomen that may be caused by diverse processes, such as

gastroesophageal reflux, peptic ulcer disease, and “nonulcer dyspepsia,”

2411 Gastrointestinal Endoscopy CHAPTER 322

A B

C

FIGURE 322-41 Gastrointestinal vascular ectasias. A. Gastric antral vascular ectasia (“watermelon stomach”) characterized by stripes of prominent flat or raised vascular

ectasias. B. Cecal vascular ectasia. C. Radiation-induced vascular ectasias of the rectum in a patient previously treated for prostate cancer.

a heterogeneous category that includes disorders of motility, sensation, and somatization. Gastric and esophageal malignancies are less

common causes of dyspepsia. Careful history-taking allows accurate

differential diagnosis of dyspepsia in only about half of patients. In

the remainder, endoscopy can be a useful diagnostic tool, especially

in patients whose symptoms are not resolved by Helicobacter pylori

treatment or an empirical trial of acid-reducing therapy. Endoscopy

should be performed at the outset in patients with dyspepsia and alarm

features, such as weight loss, obstructive symptoms, or iron-deficiency

anemia.

■ GASTROESOPHAGEAL REFLUX DISEASE

When classic symptoms of gastroesophageal reflux are present, such

as water brash and substernal heartburn, presumptive diagnosis and

empirical treatment are often sufficient. Endoscopy is a sensitive test

for diagnosis of esophagitis (Fig. 322-51), but it will miss nonerosive reflux disease (NERD) since some patients have symptomatic

reflux without esophagitis. The most sensitive test for diagnosis of

gastroesophageal reflux disease (GERD) is 24-h ambulatory pH monitoring. Endoscopy is indicated in patients with reflux symptoms refractory to antisecretory therapy; in those with alarm symptoms, such as

dysphagia, weight loss, or gastrointestinal bleeding; and in those with

recurrent dyspepsia after treatment that is not clearly due to reflux on

clinical grounds alone. Endoscopy should be considered in patients

with long-standing (≥10 years) GERD, as they have a sixfold increased

risk of harboring Barrett’s esophagus compared to patients with <1 year

of reflux symptoms.

Barrett’s Esophagus and Esophageal Squamous Dysplasia

Barrett’s esophagus is specialized columnar metaplasia that replaces

the normal squamous mucosa of the distal esophagus in some persons

with GERD. Barrett’s epithelium is a major risk factor for adenocarcinoma of the esophagus and is readily detected endoscopically, due to

proximal displacement of the squamocolumnar junction (Fig. 322-6).

2412 PART 10 Disorders of the Gastrointestinal System

A

B

C

FIGURE 322-42 Colonic diverticula.

FIGURE 322-43 Diverticular hemorrhage. A. Actively bleeding sigmoid diverticulum.

B. Treatment of the bleeding vessel at the dome of the diverticulum with a contact

thermal probe. C. Hemostasis secured following contact coagulation with tattoo

injection to aid future localization.

A screening EGD for Barrett’s esophagus should be considered in

patients with a chronic (≥10 year) history of GERD symptoms. Endoscopic biopsy is the gold standard for confirmation of Barrett’s esophagus and for dysplasia or cancer arising in Barrett’s mucosa.

Periodic EGD with biopsies is recommended for surveillance of

patients with Barrett’s esophagus. Endoscopic resection (EMR or ESD)

and/or ablation are performed when high-grade dysplasia or intramucosal cancer are found in the Barrett’s mucosa. Both endoscopic

therapy and periodic surveillance are acceptable options in patients

with Barrett’s esophagus and low-grade dysplasia. Radiofrequency

ablation (RFA) is the most common ablative modality used for endoscopic treatment of Barrett’s esophagus, and other modalities, such as

cryotherapy, are also available.

Esophageal squamous dysplasia is the precursor lesion of esophageal squamous cell cancer (ESCC), the most common type of esophageal malignancy worldwide. Endoscopic detection of esophageal

squamous dysplasia often requires specialized imaging methods,

such as chromoendoscopy with Lugol’s iodine. Once detected, it can

be treated endoscopically with EMR, ESD, or RFA (Fig. 322-52).

Population-based screening for esophageal squamous dysplasia has

been shown to decrease the occurrence of ESCC in high-incidence

regions.

■ PEPTIC ULCER

Peptic ulcer classically causes epigastric gnawing or burning, often

occurring nocturnally and promptly relieved by food or antacids.

Although endoscopy is the most sensitive diagnostic test for peptic

ulcer, it is not a cost-effective strategy in young patients with ulcer-like

dyspeptic symptoms unless endoscopy is available at low cost. Patients

with suspected peptic ulcer should be evaluated for H. pylori infection.

Serology (past or present infection), urea breath testing (current infection), and stool tests are noninvasive and less costly than endoscopy

with biopsy. Patients aged >50 and those with alarm symptoms or

persistent symptoms despite treatment should undergo endoscopy to

exclude malignancy.

■ NONULCER DYSPEPSIA

Nonulcer dyspepsia may be associated with bloating and, unlike peptic

ulcer, tends not to remit and recur. Most patients describe persistent

symptoms despite acid-reducing, prokinetic, or anti-Helicobacter therapy and are referred for endoscopy to exclude a refractory ulcer and

assess for other causes. Although endoscopy is useful for excluding

other diagnoses, its impact on the treatment of patients with nonulcer

dyspepsia is limited.

2413 Gastrointestinal Endoscopy CHAPTER 322

FIGURE 322-44 Esophageal food impaction. Meat bolus impacted in the distal

esophagus.

FIGURE 322-45 Esophageal foreign body. Intentionally ingested toothbrush

impacted in the esophageal lumen.

A

B

C

FIGURE 322-46 Gastric outlet obstruction due to pyloric stenosis. A. Nonsteroidal

anti-inflammatory agent–induced ulcer disease with severe stenosis of the pylorus

(arrow). B. Balloon dilation of the stenosis. C. Appearance of pyloric ring after

dilation.

■ DYSPHAGIA

About 50% of patients presenting with difficulty swallowing have a

mechanical obstruction; the remainder has a motility disorder, such

as achalasia or diffuse esophageal spasm. Careful history-taking often

points to a presumptive diagnosis and leads to the appropriate use of

diagnostic tests. Esophageal strictures (Fig. 322-53) typically cause

progressive dysphagia, first for solids, then for liquids; motility disorders often cause intermittent dysphagia for both solids and liquids.

Some underlying disorders have characteristic historic features: Schatzki’s

ring (Fig. 322-54) causes episodic dysphagia for solids, typically at the

beginning of a meal; oropharyngeal motor disorders typically present

with difficulty initiating deglutition (transfer dysphagia) and nasal

reflux or coughing with swallowing; and achalasia may cause nocturnal

regurgitation of undigested food.

When mechanical obstruction is suspected, endoscopy is a useful

initial diagnostic test, since it permits immediate biopsy and/or dilation of strictures, masses, or rings. The presence of linear furrows

and multiple corrugated rings throughout a narrowed esophagus should

raise suspicion for eosinophilic esophagitis, an increasingly recognized

cause of recurrent dysphagia and food impaction (Fig. 322-55). Blind

or forceful passage of an endoscope may lead to perforation in a patient

with stenosis of the cervical esophagus or a Zenker’s diverticulum

(Fig. 322-56), but gentle passage of an endoscope under direct visual

guidance is reasonably safe. Endoscopy can miss a subtle stricture or

ring in some patients.

When transfer dysphagia is evident or an esophageal motility disorder is suspected, esophageal radiography and/or a video-swallow study

are the best initial diagnostic tests. The oropharyngeal swallowing

mechanism, esophageal peristalsis, and the lower esophageal sphincter

can all be assessed. In some disorders, subsequent esophageal manometry is required for diagnosis.

Various causes of dysphagia are amenable to endoscopic therapy. Benign strictures, rings, and webs can be dilated using a

2414 PART 10 Disorders of the Gastrointestinal System

A

B

C

FIGURE 322-47 Sigmoid volvulus with the characteristic radiologic appearance of

a “bent inner tube.”

A

B

FIGURE 322-48 Acute colonic pseudoobstruction. A. Acute colonic dilation

occurring in a patient soon after knee surgery. B. Colonoscopic placement of

decompression tube with marked improvement in colonic dilation.

FIGURE 322-49 Obstructing colonic carcinoma. A. Colonic adenocarcinoma

causing marked luminal narrowing of the distal transverse colon. B. Endoscopic

placement of a self-expandable metal stent. C. Radiograph of expanded stent

across the obstructing tumor with a residual waist (arrow).

through-the-scope balloon (Fig. 322-57) or a polyvinyl dilator passed

over a guide wire. In some instances, fibrotic strictures may respond to

needle-knife electroincision (Fig. 322-58) when they prove refractory

to dilation. Self-expanding esophageal stents can be used to palliate

dysphagia from malignant obstruction (Fig. 322-59), and flexible

endoscopic myotomy is an option for Zenker’s diverticulum (Video

V5-19). Recent advances in submucosal endoscopy have enabled the

development of procedures, such as POEM (Video V5-20) and POET

(Video V5-21), for the management of achalasia and select subepithelial esophageal tumors, respectively.

■ ENDOSCOPIC TREATMENT OF OBESITY

A significant proportion of Americans are overweight or obese,

and obesity-associated diabetes has become a major public health

problem. Bariatric surgery is the most effective weight-loss intervention, decreasing long-term mortality in obese persons, but many

patients do not undergo surgery. Endoscopic treatments for obesity

have been developed and include insertion of an intragastric balloon

or duodenojejunal bypass liner, placement of a percutaneous gastric

tube for aspiration of gastric contents after meals, or endoscopic sleeve

gastroplasty, which utilizes endoscopic suturing to narrow the lumen

of the gastric body (Video V5-22). Prospective trials show that these

treatments induce total-body weight loss of 7–20% and provide varying degrees of glycemic control. Additional endoscopic modalities are

2415 Gastrointestinal Endoscopy CHAPTER 322

A B C

FIGURE 322-50 Methods of bile duct imaging. Arrows mark bile duct stones. A. Endoscopic ultrasound (EUS). B. Magnetic resonance cholangiopancreatography (MRCP).

C. Helical computed tomography (CT).

A B

C D

FIGURE 322-51 Causes of esophagitis. A. Severe reflux esophagitis with mucosal ulceration and friability. B. Cytomegalovirus esophagitis. C. Herpes simplex virus

esophagitis with target-type shallow ulcerations. D. Candida esophagitis with white plaques adherent to the esophageal mucosa.

2416 PART 10 Disorders of the Gastrointestinal System

A B

C D

FIGURE 322-52 Early squamous cell cancer. A. Nodularity in the distal esophagus due to T1 esophageal squamous cell cancer. B. Lesion is unstained under Lugol’s iodine

chromoendoscopy without additional unstained areas. C. Circumferential mucosal incision around the lesion. D. Resection defect following en bloc removal of the lesion

via endoscopic submucosal dissection.

undergoing clinical trials. The long-term efficacy of endoscopic bariatric treatment in comparison to surgery is still unclear.

■ TREATMENT OF MALIGNANCIES

Endoscopy plays an important role in the treatment of gastrointestinal

malignancies. Early-stage malignancies limited to the mucosal and

superficial submucosal layers may be resected using the techniques

of EMR (Video V5-4) or ESD (Video V5-5). RFA and cryotherapy are

effective modalities for ablative treatment of high-grade dysplasia and

intramucosal cancer in Barrett’s esophagus (Video V5-23). Gastrointestinal stromal tumors can be removed en bloc by EFTR (Video V5-3).

In general, endoscopic techniques offer the advantage of a minimally

invasive approach to treatment but rely on other imaging techniques

(such as CT, MRI, positron emission tomography [PET], and EUS) to

exclude distant metastases or locally advanced disease better treated by

surgery or other modalities. The decision to treat an early-stage gastrointestinal malignancy endoscopically is often made in collaboration

with a surgeon and/or oncologist.

Endoscopic palliation of gastrointestinal malignancies relieves

symptoms and, in many cases, prolongs survival. Malignant obstruction can be relieved by endoscopic stent placement (Figs. 322-18, 322-49,

322-59, and 322-60; Videos V5-16 and V5-17), and malignant gastrointestinal bleeding can often be palliated endoscopically as well. EUSguided celiac plexus neurolysis may relieve pancreatic cancer pain.

■ ANEMIA AND OCCULT BLOOD IN THE STOOL

Iron-deficiency anemia may be attributed to poor iron absorption

(as in celiac sprue) or, more commonly, chronic blood loss. Intestinal

bleeding should be strongly suspected in men and postmenopausal

women with iron-deficiency anemia, and colonoscopy is indicated in

such patients, even in the absence of detectable occult blood in the

stool. Approximately 30% will have large colonic polyps or colorectal

cancer, and a few patients will have colonic vascular lesions. When a

convincing source of blood loss is not found in the colon, upper gastrointestinal endoscopy should be considered; if no lesion is found,

duodenal biopsies should be obtained to exclude sprue (Fig. 322-61).

Small-bowel evaluation with capsule endoscopy (Fig. 322-62), CT or

magnetic resonance (MR) enterography, or device-assisted enteroscopy

may be appropriate if both EGD and colonoscopy are unrevealing.

Tests for occult blood in the stool detect hemoglobin or the heme

moiety and are most sensitive for colonic blood loss, although they will

also detect larger amounts of upper gastrointestinal bleeding. Patients