Novel Bipolar Radiofrequency Ablation Knife in Esophageal Lesions

Endoscopic submucosal dissection (ESD) is a novel technique for the removal of esophageal lesions or polyps with high-risk features. ESD is minimally invasive and allows the removal of esophageal polyps without resorting to morbid surgery. The process of ESD includes marking the lesions selected for removal, followed by submucosal injection of a lifting agent, then circumferential incisions using a specialized knife followed by submucosal dissection of the entire lesion. Traditionally, knifes utilizing monopolar current were the preferred tools for endoscopic submucosal dissection. These knifes allow accurate dissection and excellent hemostasis. However, due to monopolar current generated heat, post coagulation syndrome can be seen in up to 8 to 40 % of patients. Post coagulation syndrome present with pain, fever and leukocytosis and requires supportive treatment with IV fluid and antibiotics. In addition, for large esophageal lesions, stricturing can occur after resection due to significant scar formation resulting from the tissue healing response to electrocautery. Almost all patients with \>60% of the esophageal circumference removed via monopolar knives, will develop an esophageal stricture at some point. These patients require serial esophageal dilations, and although easily managed, its development can be quite troublesome to the patient. Nevertheless, ESD is still the preferred modality for removal of these lesions since it avoids the need for morbid surgery. Recently, a novel Bipolar RFA knife was FDA approved for endoscopic submucosal dissection. The low voltage bipolar system allows for precise cutting of submucosa and muscle using substantially less energy, thereby limiting inadvertent remote thermal effects. Additionally, it allows aggressive coagulation of vessels without dissipation of large amounts of energy, thereby allowing more targeted therapy. Moreover, with the addition of an integrated injection needle, the knife now allows injection, safe cutting and coagulation in one device, potentially supporting more efficient dissection. Ultimately, due to less thermal effect on surrounding tissue, the bipolar knife may allow for removal of large esophageal lesions without causing major esophageal stricturing.