href="#ulink_3fa7fe7d-f923-533c-8664-0cdb49ede50a">Figure 5.6 White light HRE view of normal duodenal folds. The villiform architecture is readily discernible (Medical University of South Carolina, Charleston, USA).
(Contributed with permission from Advanced Digestive Endoscopy: Comprehensive Atlas of High‐Resolution Endoscopy and Narrowband Imaging. Edited by J. Cohen. Blackwell Publishing. 2007: p. 246.)
Endoscope accessories include a variety of forceps and snares, guidewires for subsequent placement of motility catheters or stents, brushes to obtain specimens for microbiology or cytology, baskets, injection needles, clips, band ligators, probes for thermal coagulation, and argon plasma coagulation, through‐the‐scope (TTS) balloon dilators, and stents.
Diagnostic endoscopy
Patient positioning
Patient positioning is important to a successful examination. The patient should lie on his or her left side, which facilitates insertion of the endoscope and may reduce aspiration by allowing gastric contents to pool in the fundus. A small pillow may be used to support the patient's head. One exception to the left lateral position is during placement of a PEG tube where the patient would be placed in the supine position. Vital signs should be obtained prior to initiation of moderate sedation, and nasal oxygen administered. A bite block, either with or without a neck strap, should be placed prior to the administration of moderate sedation. The patient should be instructed not to talk to the physician or staff after administration of sedation to allow the intended effects of sedation to occur and so that appropriate response to sedation can be monitored.
The trainee should be instructed not to point the endoscope tip at the patient until adequate sedation has been administered, as the light from the endoscope may distract the patient and result in the need for additional medications for moderate sedation. Some physicians place a washcloth over the patients' eyes in order to prevent the distraction from visualization of the endoscopy equipment, especially if the patient is undergoing the procedure without sedation. When it is time to start the procedure, the endoscopist should stand acing the patient with the endoscope held directed toward the patient's mouth. The patient's head should be flexed with the chin toward the chest, to facilitate esophageal intubation.
The trainee should be instructed to hold the control head of the endoscope in his/her left hand, using the thumb and third or fourth finger to control the up/down and left/right angulation knobs (Figure 5.9). The forefinger and thirrd finger can be applied to the suction and air/water buttons as needed. The trainee should be encouraged to learn to use the left hand to control both knobs and buttons rather than taking the right hand away from the endoscope to help control the knobs, as this technique may lead to loss of endoscope position and increased loop formation particularly during colonoscopy.
Figure 5.7 White light HRE view of (a) esophageal squamous cell carcinoma (SCC) (University of Amsterdam, Amsterdam, Netherlands), (b) a gastric inlet patch upon slow withdrawal of the endoscope from the esophagus (Mount Sinai School of Medicine, New York City, USA), (c) multiple tiny white plaques suggesting candidiasis that actually represent eosinophilic esophageal microabscesses (NYU School of Medicine, New York City, USA), (d) smooth benign esophageal stricture (Mayo Clinic, Jacksonville, USA), (e) white, curd‐like exudate of Candidal esophagitis (endoscopic appearance is sufficient to make this diagnosis) (Mayo Clinic, Jacksonville, USA), (f) Nissen‐type fundoplication with intact wrap (Mayo Clinic, Jacksonville, USA), (g) early gastric carcinoma in a background of intestinal metaplasia and atrophy (University of Amsterdam, Amsterdam, Netherlands), (h) benign appearing gastric ulcer with smooth regular borders (Institut Arnault Tzanck, Saint‐Laurent‐du‐Var, France), (i) Brunner's gland hyperplasia of the duodenal bulb (Institut Arnault Tzanck, Saint‐Laurent‐du‐Var, France), (j) arteriovenous malformation (Mayo Clinic, Jacksonville, USA), (k) bile duct adenoma with high‐grade dysplasia (note yellow‐colored bile) (Mayo Clinic, Jacksonville, USA), and (l) complete villous atrophy (Institut Arnault Tzanck, Saint‐Laurent‐du‐Var, France).
(Contributed with permission from Advanced Digestive Endoscopy: Comprehensive Atlas of High‐Resolution Endoscopy and Narrowband Imaging. Edited by J. Cohen. Blackwell Publishing. 2007: pp. 170, 208, 207, 206, 178, 239, 229, 223, 246, 260, 256, 259.)
It is preferable and safer to teach insertion of the endoscope using the direct visual technique rather than under finger guidance. The latter technique may be needed rarely, however, if the patient is unable to swallow the endoscope upon command. Under direct visualization, the trainee should first align the scope so that the tongue will be at the top of the screen as the scope is inserted into the mouth. The tip of the endoscope should be gently advanced over the midline of the tongue, past the uvula and the epiglottis as the up/down knob is rotated counterclockwise with moving the left thumb down. If the teeth are visualized, the endoscope should be withdrawn and reintroduced. Once the base of the vocal cords is visualized, the tip of the endoscope should be placed under the cricoarytenoid cartilage on either side with temporary nonvisualization of the mucosa (Figure 5.10). The trainee should ask the patient to swallow and maintain gentle pressure so that the instrument will be directed into the proximal esophagus. Trainees should be alerted to the relatively rare possibility of entering a Zenker's diverticulum. If this occurs, the endoscope should be slowly withdrawn while searching for the entrance to the esophagus. If esophageal intubation is not easily achieved, more sedation may be required for patients who still have a strong gag reflex or a more experienced endoscopist should attempt intubation.
Figure 5.8 Recommended grip technique for the endoscope with left index and middle fingers free to activate suction and air/water buttons and thumb to control up/down and left/right dials.
Figure 5.9 (a) Upward tip deflection demonstrated with the thumb pushing the up/down dial counterclockwise. (b) Leftward tip deflection shown with the left/right dial rotated counterclockwise.
Figure 5.10 White light HRE view showing erythema of the aryepiglottic folds in this patient with endoscopically confirmed
