Innovative noninsufflation EFTR: sufficient endoscopic operative field by mechanical counter traction device

No reliable pure natural orifice transluminal endoscopic surgery (NOTES) mechanical counter traction (MCT) device for the flexible endoscope to obtain a sufficient surgical endoscopic field has yet been developed. Our experience with 10 cases of hybrid NOTES prompted the realization of the importance of an MCT device for the flexible endoscope and inspired us to establish innovative noninsufflation endoscopic full-thickness resection (EFTR) with an MCT device.

We performed 40 EFTR 40 mm in diameter on excised whole porcine stomachs. Twenty were resected by an MCT device to obtain a surgical field (MCT group), and another 20 were resected with a conventional endoscopic attachment (control group). We evaluated the successful resection rates of EFTR and procedure times between two groups. Next, we implemented EFTR with a custom prototype MCT device in three cases of stomach pseudotumors in female dogs. Gastric pseudotumors ~40 mm in diameter were marked within the open surgical field created by the MCT device. After resecting the pseudotumors, we conducted full-thickness suturing using over-the-scope clips.

In the MCT group, all 20 cases were completely resected. On the other hand, in the control group, only 8 cases were performed via EFTR (P < 0.01). The mean ± standard deviation EFTR procedure times for the MCT and control groups were 4.13 ± 0.824 and 36.26 ± 8.67 min, respectively (P = 0.001). In three dogs, sufficient surgical working spaces were obtained up to 78 mm (range, 65-78 mm), and full-thickness resections were performed safely and sutured with over-the-scope clips.

Our new prototype MCT device effectively obtains a sufficient surgical endoscopic field during EFTR. We are developing a new MCT with a bending function to perform EFTR in any location in the stomach.