Endoscope for removal of tissue

An endoscope for resecting tissue inside body cavities, the principal feature of which is that the endoscopic tube contains a shaft carrying a grinding or milling head, which allows precise removal of scar tissue or other fairly firm tissue under endoscopic control without leaving irregular or thermally damaged wound sites.

BACKGROUND AND SUMMARY OF THE INVENTION 
This invention is directed to an improved endoscope for removing scar 
tissue that is constricting hollow organs of the body. It was an object of 
the invention to provide a means for removing tissue under visual control 
with high precision and in a manner that is as unstressful to the patient 
as possible. 
The endoscopes that have been used up to now to remove tissue under visual 
control have involved electrical surgery, a surgical knife, or a punching 
device. The devices have not been entirely successful in that electrical 
surgery will leave a more extensive zone of dead tissue due to heat 
development; a surgical knife is very difficult to use due to the very 
small operation site and because of the limited minipulability of the 
cutting element, and punching or nipping devices in the form of small 
forceps cause uncontrolled tearing of the tissue, which leads to irregular 
wound areas. 
The present invention allows tissue resection by means of a grinding or 
milling process under endoscopic observation. The grinding or milling head 
connected to a rotating shaft is advanced toward the tissue to be removed 
under visual control, and the tissue is then slowly resected under 
constant observation, preferably by means of the cutting surfaces of small 
diamonds provided on the grinding head. The present method allows 
millimeter-precise operation without leaving an extended zone of dead 
tissue, as the grinding process takes place without any significant 
temperature. The device further provides the continuous flushing required 
for good endoscopic vision which also assures continuous cooling during 
the grinding operation. The resulting wound areas are smooth and can be 
exactly adapted to the normal shape of the organ.

DETAILED DESCRIPTION 
The outer tube 3 of the endoscope 1 is preferably made of metal such as 
stainless steel or an alloy corresponding to the state of the art. As can 
best be seen in FIG. 3, tube 3 accommodates a tube 4 for the lens system 
and cold light guide and rotating shaft 5 with its bearing 6. The inlet 
connection 9 for flushing solutions allows the flushing solution to flow 
between the lens tube and the bearing of the rotating shaft through the 
endoscopic tube to the tip 2 of the endoscope and to flush the operation 
site clear. 
The tubing 4 containing the lens system and the cold light guide as well as 
the bearing for the rotating shaft 6 is stabilized by one or more brackets 
8 located within tube 3. The rotating shaft 5 carries the grinding head 7 
which is provided with a screw connection for replacement purposes. A 
conventional locking ring 10 seals off the endoscopic tube and is 
connected with a sealing element 11 which is firmly fixed to the tube 4 
containing the lens system with cold light guide, and which has one end of 
spring 17 fixed to its lower part. This spring 17 which is fastened at its 
other end to the drive unit, pushes the drive unit 23 away from the 
endoscopic tube. The drive unit can be displaced on the tube 4 containing 
the lens system and cold light guide as well as on a special guide rail 20 
between the endoscopic tube with its locking element 11 and a limit stop 
plate firmly connected to the tube 4 for lens system and cold light guide 
against the pressure of the spring 17. These movements are controlled by 
the surgeon's hand holding the instrument by placing a finger into the 
ring 16 and gripping the handle. 
When the bearing of the rotating shaft enters into the drive unit 23, the 
bearing will be fixed in its position by means of a conventional locking 
device 18 which may, for example, be in the form of a clamp attached to 
driving unit 23 and engaging tube 6. The conical wheel of the rotating 
shaft 21 meets the conical wheel of the flexible shaft 22 within chamber 
34 contained within the drive unit 23. The flexible shaft 24 is fixed to 
the drive unit by means of a standard locking device 25. The standard 
locking device 13 fastens the lens system with cold light guide within its 
respective tube 4. Cold light is introduced through inlet 14, and the 
eyepiece of the lens system 15 forms the rear end of the endoscope. 
Another embodiment of the invention is shown in FIG. 4. In this embodiment, 
the conical wheel 22 of the electric motor 31 which is supplied with 
electric current via a feeder cable 35. The drive unit 23 slides on tube 4 
containing optical lens and cold light guide. The drive unit 23 is moved 
on guide rods 26 against the resistance of the spring 27. These movements 
are controlled by the surgeon placing his fingers into the rings 29 and 
32. 
List of Elements 
1. Endoscope for tissue resection 
2. Endoscope tip 
3. Hollow outer tube of endoscope 
4. Tube for lens system and cold light guide 
5. Rotating shaft 
6. Bearing of rotating shaft 
7. Removable grinding head 
8. Bracket for tube containing lens systems and cold light guide, and for 
rotating shaft bearing 
9. Inlet connection for flushing solution 
10. Locking ring for endoscopic tube 
11. Locking plate firmly connected with tube containing lens system and 
cold light guide 
12. Rear limit stop plate for movable drive unit, firmly connected with 
tube containing lens system and cold light guide 
13. Locking system for tube containing lens system and cold light guide 
14. Cold light connection 
15. Eyepiece 
16. Ring for surgeon's fingers 
17. Spring 
18. Locking system for rotating shaft bearing 
19. Handle for surgeon's fingers 
20. Guide rail for drive unit 
21. Conical wheel of rotating shaft 
22. Conical wheel of flexible shaft 
23. Drive unit 
24. Connection piece of flexible shaft 
25. Locking system for flexible shaft on drive unit 
26. Guide rods for drive unit 
27. Spring for guide rods 
28. Cold light cable 
29. Ring for surgeon's fingers 
30. Flushing duct 
31. Electric motor 
32. Ring for surgeon's thumb 
33. Front lens of optical system 
34. Chamber accommodating conical wheels 
35. Electric current supply cable