Cap-assisted argon plasma coagulation

Abstract

Cap-assisted argon plasma coagulation is carried out with a clear cap over the tip of the endoscope. The catheter is then positioned within the cap in such a manner that the tip of the catheter is kept at a reproducible distance from the mucosa (Fig. 1). This obviates the possibility of direct mucosal contact and the resulting direct thermal injury. It also allows for a very precise delivery of current to the target tissues by maintaining the position of the endoscope tip and catheter tip relative to the intended treatment area, maintaining luminal patency, and controlling the local gas dynamics of the argon. This technique does not appear to be widely used and has not been described in the medical literature, to our knowledge, but we suspect that some endoscopists may find it helpful. Video 1 (available online at www. giejournal.org) demonstrates this technique by use of a single-use, soft, straight cap (Olympus, Tokyo, Japan) to ablate radiation proctopathy in a symptomatic 68year-old man.