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Hook Knife

Model KD-620QR/UR

Basic specifications

Distal end

Cutting knife length: 4.5 mm
Hook length: 1.3 mm
Cutting knife diameter: 00.4 mm



Max. insertion portion diameter: 02.6 mm
Working length:

KD-620QR – 1,950 mm
KD-620UR – 2,300 mm

Electrosurgical settings and tips on using the Hook Knife

Dr.Shinji Tanaka Electrosurgical ICC-200 unit Cautions and Tips on Use
  Mucosal incision EndoCnt Effect 3, 80 W

●It is important not to point the distal end toward the muscle layer. If the Hook Knife is activated while the distal end is contacting the muscle layer, perforation could easily occur.


●During dissection, hook the submucosa and pull the knife toward the center of the lumen and continue dissection.


●By contacting the submucosa with the Hook Knife when the submucosa is extended, you can create an edge to firmly hook the knife on.



●Although it is possible to use the ITknife or needle knife-style cutting technique with the Hook Knife, care is required because cutting this way can be risky if a good field of view is not secured.

  Submucosal dissection Forced Coag., 40-50 W
  Haemostasis Forced Coag., 50 W
Dr.Naohisa Yahagi ElectrosurgicalI unit VI0300D Cautions and Tips on Use
  Mucosal incision EndoCutQ, Effect2, Duration2, Interval2 Dry Cut Effect2, 40W ●Basically, manipulate the knife so that it is pointed toward the center of the lumen.
●When rotating the scope during the procedure, note that the orientation of the Hook Knife changes according to the rotation.
Make sure to confirm the final orientation of the Hook Knife before manipulating it.
  Submucosal dissection Swift Coag. Effect4, 40W
  Haemostasis Swift Coag. Effect4, 40W
Dr. Yoshiro Tamegai Electrosurgical VI0300D Cautions and Tips on Use
  Mucosal incision EndoCutQ, Effect2,Duration2-4, Interval4-6 ●In my case, I incise and dissect the mucosa by keeping the Hook Knife projected a little from the scope and move the scope with a gliding motion, while keeping it a certain distance away from the lesion using an attachment. To ensure safety, I always move the Hook Knife carefully.
●Controlling the scope angulation and the torque allows you to handle the knife with the necessary precision. I try to straighten the scope so that the endotherapy device can be manipulated as intended.
The high-frequency current should be supplied intermittently, and the foot should always be ready to release the footswitch to stop the current supply at any time.
●Safety can be assured by observing the hook portion at the distal end of the Hook Knife under the mucosa during the mucosal incision. During dissection, the distal end should be oriented toward the dissecting direction or to the opposite side of the proper muscle layer. The sweeping technique (intermittent current supply while tracing the back of the knife along the arc of the intestinal tract) is most used. Areas that need a delicate touch are dissected by hooking the tissue.
For Safer and More Appropriate Use
Information on this page provided by Olympus
  Submucosal dissection Swift Coag. Effects, SOW
  Haemostasis Soft Coag. Effects, SOW

Case with Hook Knife

For Safer and More Appropriate Use

Information on this page provided by Olympus

Basic Operation of Hook Knife (Rotation)

1 Hold and pull the slider until the hook is slightly withdrawn. This makes the hook rotatable.

2 While holding the sheath, turn the handle slowly and align the direction of the hook.
*Rotation can be facilitated by removing the A-cord. *If rotation is difficult, move the slider back and forth.

3 Push the slider and extend the cutting knife. By maintaining it, the rotation of the hook is locked.

Please note that under some conditions, damage such as melting of the distal end or stretching of the hook may occur. In particular, under the circumstances outlined below, an excessive load is likely to be imposed on the knife, increasing the risk that the knife will be damaged.

Conditions that impose a heavy load on the knife and countermeasures

1 When the current is activated while the knife is in contact with the tissue under high-moisture conditions:

Before activation, remove moisture, including mucus and blood, from the region before contacting it with the endotherapy device.

2 When the electrosurgical unit is set to a high-voltage waveform and activation is continued for an extended period:

Reduce the use of high-voltage waveforms to the minimum required level. Keep the activation period as short as possible when using a high-voltage waveform.

Electrosurgical unit: Voltage intensities of various waveforms
Cut / Soft Coagulation < Blend < Coagulation < Spray Coagulation∗2 (e.g., APC mode)


∗1 Long period of activation using a high-voltage waveform may increase invasion in deep tissue.
∗2 Spray Coagulation mode cannot be used with this instrument.

3 When the knife is subjected to excessive force at the time of retraction into the sheath or during removal of tissue attached to the knife:

Be careful not to apply excessive force when removing tissue attached to the knife.

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