12 Upper Gastrointestinal Endoscopy
Philip W.Y. Chiu and Rajvinder Singh
12.1 History of Upper Gastrointestinal Endoscopy
The development of endoscopy can be traced back to the ancient Roman time where archeologists discovered the vaginal speculum at the ruins of Pompeii. 1 In 1853, Desormeaux first proposed the concept of endoscope and its essential components, including optical body and light source. In 1868, Kussmaul first performed upper endoscopy through a rigid tube, but the examination was far from satisfactory because of the poor light illumination. 2 Johann Mikulicz, being the first surgeon to perform suture repair of perforated gastric ulcer, developed improved models and performed the first esophagogastroscopy in 1881. His modifications included mirrors to produce 30-degree-angled field of vision and a miniature version of Thomas Edison’s electric incandescent globe as the light source. He was first to describe the endoscopic observation of gastric carcinoma. The concept of flexible endoscope was introduced by Henry Elsner in 1911 where the endoscope was created with both rigid and flexible parts. Rudolph Schindler, a gastroenterologist, modified the Elsner two-part gastroscope to include a separate channel for flushing of lens and developed the Wolf–Schindler gastroscope in the 1930s. This scope consisted of multiple prisms for transmission of images and a bending angle of 30 to 34 degrees. This scope became widely adopted due to the safety and efficacy. Diagnostic endoscopy was enhanced by the developments in flexible fiberoptics in 1954 by Harold Hopkins at the Imperial College of London. 3 The Hopkins system consisted of glass rods coated in reflective cladding, permitting high-intensity light transmission and image transmission. Dr. Basil Hirschowitz from University of Michigan produced a prototype flexible gastroscope based on these fiberoptic bundles and performed the first gastroscopy on himself and subsequently on a patient in 1957. 4 The enhancement of optical fibers further enhanced the development of endoscope. The introduction of videoendoscopy further revolutionized the performance of endoscopic examination. In 1983, charge-coupled device (CCD) was used to replace coherent fiberoptic image bundle by the Welch Allyn Company to capture images focused by a small lens. The image was converted to display on a TV monitor. 5 , 6 This allowed the endoscopist, trainees, and nurses to appreciate the endoscopic examination together and unleash the possibility of therapeutic endoscopy. 7
The modern gastroscopes are forward-viewing endoscopes with a short insertion shaft dedicated for examination of the esophagus, stomach, and duodenum (▶Table 12.1). 8 The length of the insertion tube varies between 925 and 1,100 mm, and the diameter varies from 4.9 to 12.8 mm depending on the functionality and indications. A typical gastroscope has one working channel and the size varies from 2 to 3.8 mm, and a dual-channel gastroscope is available for specific therapeutic purpose. An ultrathin endoscopy is also available with a diameter between 4.9 and 6 mm and a working channel of 1.5 to 2 mm. 9 This can be used for transnasal or transoral upper endoscopic examination to alleviate patients discomfort without sedation, as well as negotiation through tight constrictive upper gastrointestinal (GI) tumors.
12.2 General Diagnostic Techniques
Generally, upper GI endoscopy is indicated as an investigation for patients who have symptoms relating to upper GI diseases. The American Society for Gastrointestinal Endoscopy (ASGE) guidelines for appropriate use of GI endoscopy described indications for esophagogastroduodenoscopy (EGD). 10 For patients with symptoms of upper GI diseases, endoscopists should be alerted of the differential diagnosis related to these symptoms and search for those diseases during upper endoscopy. Patients with upper abdominal symptoms associated with alarm signs and symptoms, and those with new-onset dyspepsia who are older than 50 years should receive early EGD. For patients with symptoms of upper GI hemorrhage, the most common pathologies include bleeding peptic ulcers, variceal bleeding, bleeding from upper GI malignancies, and hemorrhagic gastritis. For patients with dysphagia, upper endoscopy is indicated to examine for presence of esophageal cancer and cancer at the cardia of the stomach. However, as upper endoscopy is not the most appropriate investigation for functional diseases, patients with dysphagia and a normal endoscopy should be further investigated with high-resolution manometry to rule out esophageal dysmotility disorders including achalasia, and 24-hour pH study for chronic gastroesophageal reflux disease (GERD). Patients with symptoms of gastroesophageal reflux which persist despite appropriate treatment should be investigated with an EGD. For patients with clinical suspicion of coeliac disease or a positive serological test, routine biopsy of the duodenum is important to rule out villous atrophy.
Axon et al reported the guidelines on indications for performance of upper GI endoscopy. 11 The guidelines were set for referral of EGD based on appropriate symptoms and indications from evaluation of systematic reviews of published data and recommendations from expert panels. The appropriate indications for EGD are summarized in ▶Table 12.2.
Upper gastrointestinal symptoms/signs
Significant upper abdominal pain
Dyspepsia (especially new onset at the age of 40)
Significant heartburn not responsive to PPI therapy
Palpable epigastric mass
Upper gastrointestinal hemorrhage
Passage of tarry stool
Coffee ground vomiting
Positive occult blood test
Unexplained weight loss
Abnormal barium meal/swallow results
Hypochromic microcytic anemia (low hemoglobin)
Indications—For Screening of Upper Gastrointestinal Cancers
There is an increase in acceptance of performing upper GI endoscopy as a screening procedure, especially in countries with high incidence of gastric cancer. Meanwhile, the cost and effectiveness of such screening program should be cautiously introduced as the prevalence of upper GI cancers varies among different countries worldwide. 12 In countries such as Japan with high prevalence of gastric cancers, national screening program started as early as the 1960s. 13 Photofluorography (or barium radiography) was employed as the screening method, and in 1983 all residents older than 40 years were recommended to receive gastric cancer screening. Five case–control studies demonstrated that screening by photofluorography in Japan significantly decreases gastric cancer mortality by 40 to 60%. Recently, gastroscopy is increasingly performed for screening of gastric cancer in Japan, 14 and studies suggested that most of the gastric cancers were diagnosed by EGD rather than photofluorography. Currently, more than 60% of gastric cancers are diagnosed at an early stage in Japan, 15 while technological advances in endoscopy and imaging will further improve the diagnosis and management. 16
The therapeutic procedures for upper GI endoscopy have been increasing over the past decades. Currently, upper GI endoscopy is indicated as primary treatment for upper GI hemorrhage. 17 Endoscopic resection with techniques such as endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) is the standard treatment for early-stage upper GI neoplasia. 18 , 19 Palliative endoscopic stenting is the optimal treatment for advanced or metastatic carcinoma of esophagus, stomach, and pancreas, which causes obstruction. 20 Upper GI endoscopy is indicated for removal of foreign bodies. Various interventions can be achieved through EGD for management of complications after upper GI and bariatric surgeries, including balloon dilatation for anastomotic strictures and stenting for leakage. 21
Indications—Intraoperative Upper Endoscopy
Recently, with the concept of endolaparoscopic approach for treatment of upper GI diseases, there is an increase in use of upper endoscopy during laparoscopic surgery. 22 , 23 The objectives for intraoperative upper endoscopy usually include the following: (1) localization of the disease/neoplasia; (2) providing endoluminal guidance to assess adequacy of the resection margins; and (3) as a combined endolaparoscopic approach for resection of early gastric neoplasia or GI stromal tumor. As gaseous insufflation is necessary to achieve good endoscopic visualization, the use of CO2 insufflation is recommended during intraoperative upper GI endoscopy to avoid overdistension of the GI tract, which may hinder further laparoscopic surgical procedures.
Upper GI endoscopy is generally contraindicated when patients are suspected to have upper GI perforations including perforated peptic ulcers. Cohort studies demonstrated therapeutic procedures, such as clipping and stenting, may be successful in the management of upper GI perforations including Boerhaave’s disease and anastomotic leakage. 21 These exceptional conditions will require careful clinical planning and availability of expertise. The other contraindication for upper GI endoscopy is an inadequate timing of fasting before the procedure, for patients with symptoms of gastric outlet obstruction and achalasia. These patients will have either food residue in the esophagus or large amount of undigested food in stomach. Performing upper GI endoscopy during these clinical conditions may induce significant regurgitation, leading to aspiration pneumonia.
In the guidelines by ASGE and guidelines published by the joint working party in England, patients with symptoms that are considered functional in origin are generally not indicated for EGD. 10 , 11 However, EGD should still be indicated to exclude mechanical causes when these symptoms persist. 24 In countries with moderate to high incidence of gastric cancers, patients with upper abdominal symptoms should receive a diagnostic EGD—“a scope and treat strategy” rather than the test and eradicate Helicobacter pylori without endoscopy, i.e., “test and treat strategy,” which is more commonly advocated in low-prevalence populations. 25