Sheath device for biportal endoscopic spinal surgery

1. A sheath device for biportal endoscopic spinal surgery, the device comprising:

a guide tube as a hollow tubular member extending in a longitudinal direction thereof and having a front end thereof reaching a target site in a patient's body when being used, the guide tube accommodating a probe of an endoscope inserted therein;

a saline solution guide part mounted on a rear end of the guide tube and guiding a saline solution injected from an outside to an inside of the guide tube, the saline solution guide part comprising a valve body making the saline solution that is flowed in through an inlet to be passed through and moved to the guide tube;

a damping chamber configured to receive and hold the saline solution once the saline solution is supplied inside the damping chamber from the valve body and prior to transferring the saline solution to the guide tube to maintain a constant flow rate of the saline solution to the guide tube;

an adapter part positioned at the rear end of the guide tube and guiding the probe of the endoscope to use to the guide tube; and

a side slit to discharge the saline solution discharged from the guide tube in one direction of the guide tube is formed at a side of the front end of the guide tube.

2. The device of claim 1 , wherein the saline solution guide part comprises:

a volume control valve mounted on the valve body and controlling a flow rate of the saline solution passing through the valve body.

3. The device of claim 1 , wherein one or more of the valve bodies are mounted around the damping chamber to increase an amount of the saline solution supplied to the damping chamber.

4. The device of claim 1 , wherein, on an inner circumference surface of the guide tube, a guide groove guiding the saline solution in the longitudinal direction of the guide tube, which is flowed into the inside of the guide tube is formed.

5. The device of claim 4 , wherein a plurality of the guide grooves is disposed in parallel in a circumferential direction of the inner circumference surface of the guide tube, and a linear protrusion contacting the probe of the endoscope and supporting the probe thereof is provided between each of the guide grooves.

6. The device of claim 1 , wherein the adapter part is provided with a holder maintaining a fixation state of the endoscope to the sheath device.

7. The device of claim 1 , wherein, at the front end of the guide tube, protrusion parts and recessed parts are repeatedly formed in a wave pattern along the circumferential direction of the guide tube, thus guiding the saline solution discharged from the guide tube to flow out in a radial direction of the guide tube.