Tunnel-and-bridge strategy for rectal endoscopic submucosal dissection: tips to allow strong countertraction without clip and line

Endoscopic submucosal dissection (ESD) is the reference method for curative resection of rectal tumors, reducing the rate of recurrence and allowing complete specimen assessment [1]. Nevertheless, it is technically challenging and new strategies to reduce the procedure time and difficulty, and to improve learning are needed [2–4]. Countertraction, as has been proposed with the clip-and-line technique, allows the submucosal space to be enlarged, making dissection easier [5]. In the rectum, the line creates tangential traction without triangulation. We present here the tunnel-andbridge strategy (▶Fig. 1 and ▶Fig. 2; ▶Video1). First, the two edges (oral and anal) of the lesion are cut, with incision followed by dissection. A tunnel is then created from the anal to the oral edge. After this step, the two lateral incisions are made without dissection. Finally, the scope is passed through the channel and retroflexion is performed above the oral side, making permanent countertraction for the procedure to be completed by cutting the two lateral submucosal residues with the scope in the retroflexed position. Because of the weight of the scope, a real triangulation is obtained. This strategy needs to be compared prospectively but seems to offer a good method of countertraction without any additional cost, such as for a clip.