Endoscopic surgery - exploring the modalities

Table 1 Characteristic of various endoscopic submucosal dissection knives

Type	Manufacturer	Description	Comments
Needle-knife type
Insulated tip knife	Olympus	Ceramic ball attached to the tip of the knife	Insulator helps to prevent perforation. Small ceramic ball is suitable to operate on thinner submucosal plane; e.g., in the esophagus and colon
Hook knife	Olympus	Tip of the knife is right-angled	Submucosal tissue is hooked and pulled before incision, lessen the risk of perforation
Flex knife	Olympus	Knife formed by soft, flexible loop cutting wire with adjustable length	Less risk of perforation. Distal end of the sheath is thick to serve as stopper to allow precise control of incision depth
Dual knife	Olympus	Small ball-like process on the tip, knife can be fixed in two positions - retracted or extended	Ball tip prevents slipping
Flush knife	Fujinon	Short needle knife that comes in 5 different projection lengths Water emission through the lumen of the needle	Water jet is activated by a foot pedal, helps to washout blood at operative field and debris at the tip of knife. Provide better visualization and less time consuming without having to switch instruments
Splashneedle	Pentax	Similar to Flush knife
Mucosectomy	Pentax	Circumferentially insulated knife with single cutting wire on the side of the tip	Insulated plastic sheath can lie on the muscular layer, allowing safe dissection by cutting wire on the submucosal plane
Grasping type scissor forceps
SB knife	Sumitomo Bakelite	Rotatable monopolar scissors, surrounded with no-conductive coating. Clawed and curved tip	Large insulated claw prevents injury to the muscular layer
Clutch Cutter	Fujinon	Thin serrated cutting scissor, insulated on the outer forcep, rotatable	Serrated edges help to grasp tissue better

Table 2 Randomised controlled trials that reported on no significant difference in major outcomes between transvaginal cholecystectomy and conventional laparoscopic cholecystectomy

Ref.	Study type	Type of TVC	Outcome
			Median/min Duration of surgery (min)		Median/min Length of stay (d)		Median/min Pain score
			TVC	CLC	TVC	CLC	TVC	CLC
Kilian et al[18]	RCT	Hybrid	68	55	3	4	1	3
Noguera et al[19]	RCT	Hybrid	64.85	47.04	1	1	3.94	4.65
Borchert et al[20]	RCT	Hybrid	65.1	64.2	2.81	2.81	1.81	2.03

These studies proved that TVC is not inferior to CLC. RCT: Randomised controlled trials; TVC: Transvaginal cholecystectomy; CLC: Conventional laparoscopic cholecystectomy.

Table 3 Summary of reported outcome data for endoscopic restrictive gastroplasty

Technique	Study design	Excess BMI/weight loss (%)	Effects of comorbidities	Postoperative complications
Transoral gastroplasty[44]	Prospective multicentre study with 67 patients enrolled	52.2% for patients with baseline BMI < 40; 41.3% for patients baseline BMI > 40	Successful reduction of HbA1c to 5.7% (baseline of 7%), improvement in triglyceride level	2 patients had respiratory insufficiency and asymptomatic pneumoperitoneum, respectively. Both were successfully managed conservatively
	Average BMI: 41.5 (range 35.0-52.7)
	Follow up period: 12 mo
Endoluminal vertical gastroplasty using Bard EndoCinch suturing system[45]	Prospective, single centre observational study	Overall EWL of 58.1%	NE	No serious adverse events reported
	Average BMI: 39.9 (range 28.0-60.2)	Patients with BMI < 35 have highest EWL of 85.1%
	Follow up period: 12 mo
Endoscopic transmural gastric plication using Incisionless Operating Platform[30]	Prospective single centre	49.4% EWL at 6 mo	NE	Minor postoperative side effects, i.e., fever, sore throat, stomach pain, nausea, vomiting and chest pain
	Average BMI: 36.7 (range 28.1-46.6)
	Follow up period: 6 mo

NE: Not evaluated; BMI: Body mass index; EWL: Excess weight loss.