Efficacy of forced coagulation with low high-frequency power setting during endoscopic submucosal dissection

Table 1 Patient and lesion baseline data in the S and F1-10 methods

	S method (n = 6)	F1-10 method (n = 6)	P3 value
Age, median (yr) (range)	70 (64-87)	71 (53-79)	0.81
Sex (male/female)	5:1	4:2	0.59
Lesion location, U/M/L1	3/3/0	4/2/0	0.64
Histology, well/mod/poor	6/0/0	6/0/0	1.00
Tumor size, median (mm) (range)	13.5 (8-36)	16 (6-23)	0.60
Resected size, median (mm) (range)	50.5 (33-64)	44.5 (31-56)	0.63
Depth of tumor invasion, M/SM1/SM22	4/2/0	3/1/2	0.42
Median time of treatment (min)	65	52.5	0.69
Postoperative bleeding rate	0	0	1.00
En bloc resection rate	100%	100%	1.00

¹The three portions of the stomach;

²Depth of tumor invasion was classified as follows: M, tumor confined to the mucosa; SM1, tumor confined within 0.5 mm of the muscularis mucosae; SM2, tumor invasion is 0.5 mm or deeper into the muscularis mucosae;

³Categorical variables were compared using the two-sided Fisher's exact test and χ² test. Continuous variables were compared using the Wilcoxon's rank-sum test. U: Upper third; M: Middle third; L: Lower third.

Table 2 Results of the vessel diameter, frequency of the compressed vessel, and coagulation time in the vessel-sealing with endoknife compression technique during gastric endoscopic submucosal dissection

	S method	F1-10 method	P1 value
Number of vessels processed by vessel-sealing	49	62
with endoknife compression
Median vessel diameter (mm) (range)	2 (1-3)	1.5 (1-3)	0.68
Median frequency of compressed vessel (times) (range)	2 (1-8)	2 (1-5)	0.11
Median time of coagulation (s) (range)	9 (2-48)	10 (1-58)	0.11

¹Continuous variables were compared using the Wilcoxon's rank-sum test.

Table 3 Rates of bleeding after vessel-sealing with endoknife compression for all vessels and large vessels

	S method	F1-10 method	P2 value	OR	95%CI
Rate of bleeding	16.3% (8/49)	4.8% (3/62)	0.058	3.84	0.96-15.34
Rate of large vessel bleeding1	26.9% (7/26)	3.4% (1/29)	0.021	10.32	1.17-90.78

¹Large vessels were defined as those with > 2 mm diameter;

²Fisher's exact test was used.

Table 4 Electrical condition using the FlushKnife-BT in the porcine ex vivo model analyzed by the VIO DOKU

	FlushKnife-BT 2.5 mm
	S method	F1-10 method
Median peak voltage (Vp)	172 (170-173)	560 (538-587)
Median current elapse time (s)	0.22 (0.20-0.30)	1.54 (0.50-1.77)
Median total electric energy (W)	6.34 (3.9-8.67)	12.5 (3.47-13.8)