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Model KD-620LR

Dr. Tsuneo Oyama
Saku Central Hospital

Interview With The Expert

What are the advantages of HookKnife?
Above all,

it’s safer than a needle knife because it hooks the mucosa for incision and dissection so it is less invasive for the deeper tissues. The rotary function provides another advantage, the ability to align the knife horizontally or vertically. Marking with the back of HookKnife will reduce the risk of perforation. In addition, safer use is possible by mounting an attachment to the endoscope’s distal end to maintain the field of view and by pulling the mucosa into the attachment before supplying current. The capability to perform dissection by directly observing the submucosal layer enables precoagulation. It is nice to be able to perform dissection with a good view and no bleeding.

Are there any weak points of HookKnife?
Due to the fact that the hook length is 1.3 mm long,

it is unavoidable to say that the cutting amount for each time is not plentiful.

Under what circumstances do you also use other devices?
I use a needle knife for circumferential incision.

The needle knife is convenient because its cutting style is like flicking the tissue. Also ITknife and FlexKnife have a higher vertical incision speed so I sometimes use them instead of HookKnife.

Applicability of HookKnife

Difficulty per region

◯ : Easy.  No mark: Ordinary.  △ : Difficult.

Cardiac region    
 Fornix  △  
 Lesser curvature of upper body  ◯  
 Greater curvature of upper body  △  
 Anterior wall of upper body    
 Posterior wall of upper body    
 Lesser curvature of middle body  ◯  
Greater curvature of middle body  △  
 Anterior wall of middle body    
 Posterior wall of middle body    
 Lesser curvature of lower body  
 Greater curvature of lower body  
 Anterior wall of lower body  
 Posterior wall of lower body  
 Lesser curvature of anterior wall    
 Greater curvature of antrum  
 Anterior wall of antrum  
 Posterior wall of antrum  
 Pyloric ring  

Recommendation for beginners: 1) It is important to begin by observing the experts’ procedures. 2) Start with UL(-) lesion of 2 cm or less.
3) After you experience about 10 cases, observe procedures performed by experts again.

Intravenous anaesthesia Premedication General anaesthesia Monitoring
Used Midazolam 5 to 7.5 mg
Butorphanol 0.5 mg
Recommended for a large lesion, a case with scar or a case in the neck region of oesophagus. Used


Electrosurgical unit VIO-300D
(Olympus Medical Systems)
Device Caution Setting
(Use the back of
the hook part.)
Make HookKnife retracted to reduce the risk of perforation. Oesophagus: SoftCoag
20W Effect4
Stomach: ForcedCoag
40W Effect2
SoftCoag 40W
Forced 40W
Local injection
  Epinephrine Indigo carmine  
glycerin fructose)*
Used Not used Oesophagus: 200X dilution / Stomach: 20X dilution. Relatively long lifting time (equivalent to 20% glucose)
Sodium retention force.
Used Not used Strongest retention force.
The muscle layer is a white cloudy thick wall, while the submucosal layer is transparent. Therefore, the two layers are easy to distinguish. The vessels in the submucosal layer can be observed more transparently when indigo carmine is not used. Also, it dies the incised sample in blue.
Circumferential incision
Device Caution Setting
HookKnife As the EndoCut mode cuts tissue a little at a time, a serious mistake does not happen even when knife control is inadequate.
AutoCut mode cuts tissue more sharply with less thermal denaturation.
60W Effect2
or EndoCut I Effect2
Duration2 Interval2
DryCut 60W Effect5
or SwiftCoag
60W Effect 3
120W Effect 3
Expert: AutoCut
120W Effect3
Submucosal dissection
Device Caution Countertraction Setting
HookKnife Use the hook part to approach perpendicularly toward the proper muscle layer. Use the arm part if approaching in parallel is allowed. Use distal attachment (D-201).
With distal attachment, dissection by suction technique is possible in the oesophagus.
A clip with attached thread can also be used.
Oesophagus, stomach:
SprayCoag 60W
Effect 2
or EndoCut I Effect2
Duration2 Interval1
Forced 60W
APC mode 60W
10 to 15W
Device Caution Setting
HookKnife Approach the back of the knife to the bleeding point and briefly supply current without contact. With ESG-100, avoid using ForcedCoag mode only. Instead, perform pre-coagulation in the SoftCoag mode before cutting in the ForcedCoag mode to prevent bleeding. SprayCoag
60W Effect2
APCmode 60W SoftCoag
Coagrasper If bleeding continues, the grasped positionv may be inappropriate. It is important to try grasping a different position. SoftCoag
80W Effect5
SoftCoag 80W SoftCoag 60W
Preventive haemostasis
Device Caution
HookKnife Small vessel about 1 mm: Hook and coagulate in the Spray or APC mode.
Coagrasper Large vessel about 2 mm: Grasp with Coagrasper and supply current for 1 or 2 seconds in the SoftCoag mode.
Perforation measure
Method Timing Tip
Clip suture Dissect to some extent before clipping to prevent the clip from interfering with subsequent treatment. Perforation made by HookKnife is about 1 × 3 mm small. A single clip can suture it and air leak is low.

* May not be available in your area.

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