Page 81 - Read Online

Page 2 of 20 Nakamura et al. Mini-invasive Surg 2022;6:50 https://dx.doi.org/10.20517/2574-1225.2022.38

INTRODUCTION
Endoscopic submucosal dissection (ESD) is currently a standard treatment for intramucosal neoplasia in the
stomach. The ESD provides about ten times higher en bloc resection rate (92.4% vs. 51.7%, OR: 9.69), five
times higher histological complete resection rate (82.1% vs. 42.2%, OR: 5.66), and one tenth recurrence rate
[1]
(0.76% vs. 6.4%, OR: 0.10) than endoscopic mucosal resection (EMR) . The effectiveness of ESD for the
treatment of EGC patients has been proven by good long-term outcomes in multicenter prospective
[2,3]
studies .
Despite excellent published outcomes, there is still a paucity of details about the basic concept and
technique of the ESD procedures. In this article, we impart practical information necessary for the proper
execution of the technique based on our experiences and currently available knowledge. We believe an
advanced procedure is accomplished with the accumulation of solid basic procedures.

PREPARATION
Equipment
Endoscopes
An endoscope with a small bending radius and a water-jet function is suitable for gastric ESD. A wide
working channel diameter of ≥ 3.2 mm, for example, the GIF-Q260J, GIF-H290T, GIF-1TH190 (all by
Olympus, Co., Ltd.), or EG-L580RD7 (Fujifilm Medical Systems, Co., Ltd.), is preferred because, in the case
of bleeding, water or air can be suctioned while the hemostatic devices are kept inserted in the working
channel.

If the lesion is located at the fornix, the gastric angle, or the anterior wall of the lower corpus, where the
endoscopic approach is difficult, a multibending video endoscope such as the GIF-2TQ260M (Olympus,
Co., Ltd.) is useful. The scope has proximal two-way bending in addition to distal four-way deflection.

Transparent attachment
For gastric ESD, a transparent attachment on the tip of the endoscope is necessary. During mucosal
incision, the attachment stabilizes the operative field and applies adequate tension to the target mucosa. In
submucosal dissection, the dissected specimen is lifted, and working space is created for continuous
submucosal dissection. In the case of bleeding, it can separate surrounding tissue around the area of
bleeding and facilitate the identification of the bleeding point. Because each device has a different
appropriate working distance, the protrusion length of the attachment must be adjusted. Usually, a long
attachment with a protrusion length of 4-6 mm is selected for the needle-type knife or scissor-type knife,
while a short attachment with a protrusion length of 2 mm is often selected for the insulated tip-type knife.
In cases of severe fibrosis or poor accessibility to the submucosal space is expected, and the tunneling
method is selected, a tapered-tip attachment, such as the ST hood (Fujifilm, Co., Ltd.), would be useful.

Insufflation gas
Two meta-analyses indicated that CO insufflation significantly reduced post-procedural abdominal pain
2
but did not affect other clinical outcomes such as en bloc resection rate, procedure time, incidence of
adverse events, etc. of gastric ESD . The influence of the type of insufflated gas may be less significant than
[4,5]
that of colonic or esophageal ESD. However, CO insufflation is advantageous over air insufflation in the
2
case of unexpected complications, especially perforation.