Osamu Dohi, MD, PhD and Yoshito Itoh, MD, PhD
In Japan, endoscopic submucosal dissection (ESD) is one of the standard treatments to achieve en bloc resection of superficial gastrointestinal (GI) neoplasms.1–3 ESD procedures for treatment of superficial GI neoplasms have rapidly spread in Japan and other East Asian countries.
Although ESD is a superior endoscopic resection technique with a high en bloc resection rate compared to endoscopic mucosal resection, there are many factors that can contribute to its potential difficulty. In such cases, ESD can be associated with higher rates of perioperative complications, with bleeding and perforation being the most commonly encountered. Once a complication occurs, ESD becomes more difficult and sometimes even impossible to complete. These technical difficulties and potential perioperative complications have slowed the dissemination of ESD and its adoption worldwide as a standard endoscopic therapy for superficial GI neoplasms.
The scissors-type electrosurgical knife is a novel, dedicated ESD device developed to reduce the risk of complications associated with endoscopic dissection. Initial clinical studies have shown that the scissors-type knives are safe and a technically efficient method for ESD.4–12 The purpose of this chapter is to introduce and describe technical aspects of ESD with the scissors-type knife and to overview the available literature on its safety and efficacy.
Tools and Techniques
The Clutch Cutter (Fujifilm) (Figure 23-1),7–9 and SB Knife (Sumitomo Bakelite)10–12 are the 2 main scissors-type electrosurgical knives available commercially. These knives can grasp and cut the target tissue using an electrosurgical current. This chapter will primarily focus on the ESD technique using the Clutch Cutter. A more detailed description of the SB Knife can be found in Chapter 11.
The Clutch Cutter has a 0.8 mm wide and 3.5 or 5.0 mm long serrated cutting edge to facilitate grasping the tissue. The diameter of the forceps is 2.7 mm. The outer side of the knife is insulated so the electrosurgical current energy is concentrated at the inner blades to avoid inadvertent thermal injury to the surrounding tissue. Furthermore, the knife can be rotated to the desired orientation. The Clutch Cutter can be used with any standard endoscope with a working channel width of 2.8 mm or larger.7,8
The ICC-200, ICC-300, VIO300D (Erbe) and ESG100 (Olympus) are the most common electrosurgical units (ESUs) used worldwide. Each ESU has different modes/settings that are particular to that company. Hence, it is important to be familiar with your ESU to program the appropriate settings for ESD. For the VIO300D, we favor using ENDO CUT I (effect 1, cut duration 4, and cut interval 1) both for mucosal incision and submucosal dissection. FORCED COAG (effect 2, 30 W) can be used for hemostasis during dissection.
Markings to delineate the outer margins of the target lesion can be safely performed with the Clutch Cutter. Circumferential markings should be placed approximately 2 to 5 mm outside the lesion’s margins using the tip of the closed Clutch Cutter with FORCED COAG (effect 3, 30 W).
Endoscopic Submucosal Dissection Procedure
The ESD procedure consists of the following steps: circumferential mucosal incision, submucosal dissection, precoagulation, and hemostasis. All of these steps can be performed with the same maneuver: (1) grasping the target tissue (fixation), (2) lifting the grasped tissue (separation of the grasped tissue from the appropriate underlying muscle layer), and (3) cutting the grasped tissue (or coagulating the blood vessel) using an electrosurgical current with ESU (Figure 23-2). All of these steps with the Clutch Cutter are relatively simple and comparable to the techniques used with hot- or cold-biopsy forceps.7–9