JPH07112478B2 - Surgical instruments - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to surgical instruments and assemblies thereof, and more specifically to surgical instruments for removing the vitreous from the eye during intraocular surgery.

[Conventional technology]

Since the posterior portion of the eye is filled with a clearing material called the vitreous, the surgical operation on the eye behind the lens is called vitreous surgery. If the vitreous is damaged, it must be completely removed before eye treatment. When the vitreous is removed, it is immediately replaced with the alternative clarification fluid.

A typical surgical instrument used for vitreous surgery is a small hand-held probe that is inserted into an incised eye. It has a tube for sucking the glass and a cutting means for drawing the glass out of the tube by suction and cutting the glass.

The instruments currently used in vitrectomy generally consist of an inner tube driven by aerodynamic diaphragms concentrically arranged within the outer tube, the outer tube extending distally from the inner tube. The outer tube has a side opening adjacent the distal tip. When a suction action is applied to the inner tube, the vitreous moves to the side opening of the outer tube. Then, when the inner tube advances axially through the aerodynamic diaphragm, the inner tube shears the glass material protruding through the hole in the outer tube. The vitreous is then aspirated from the inner tube by an external aspiration source.

The above conventional configuration has some drawbacks. The axial cutting motion of the diaphragm driven probe causes axial vibration due to the fact that the inner tube filled with the liquid is a relatively large mass and the suction tube attached to the inner tube is elastic. This causes a risk of damaging the retina and other eye structures. Axial vibration is increased by the movement of the diaphragm and the inner tube when the cutting speed is approached.

Conventional air diaphragm driven vitreous cutter tips also have other limitations. The cutting speed of such a probe is limited by the axial vibration of the instrument and the uncontrolled pumping action of the liquid in the inner tube. Liquid plugs into the closure tip of the outer tube and overflows the inner tube when removed by suction. Also, the power of the air driven diaphragm is limited by the use of return springs and the size of the diaphragm is limited by the size of the instrument probe itself. In the conventional air-driven diaphragm configurations of these surgical tips, the elastic tubing connected to the inner tube tends to propagate a dangerous oscillatory motion to the instrument when such tubing is touched during surgery.

[Problems to be Solved by the Invention]

Accordingly, a primary object of the present invention is to overcome the above drawbacks and limitations by improving the vitreous cutting probe used in removing the vitreous from the eye in ophthalmic surgery.

Another object of the present invention is to provide a surgical probe having a relatively small number of members, a simple design, and a low construction cost.

Yet another object of the present invention is to overcome the limitations and risks of using a conventional width reciprocating, air driven diaphragm vitreous cutter probe.

Still another object of the present invention is to increase the cutting speed of the surgical probe.

Still another object of the present invention is to reduce vibration while increasing the cutting speed of the device.

Yet another object of the present invention is to provide a simple and effective means of isolating a moving inner tube from an external suction means and a fixed outer tube of a surgical probe.

Other objects and advantages of the invention will be readily apparent to those of skill in the art from the following description and claims.

[Means, Actions and Effects for Solving Problems]

The present invention relates to surgical instruments, particularly cutter tips. The surgical instrument of the present invention has an outer tube having a proximal end and a distal end and having a side opening adjacent the distal end.
The side opening has a peripheral edge forming a cutting edge. Further, the device of the present invention has an inner tube concentrically housed within the outer tube and adapted to rotate relative to the outer tube. The inner tube has a proximal end and a distal end, and a portion of the inner tube extends proximally from the proximal end of the outer tube. The distal end of the inner tube is adjacent to the distal end of the outer tube, and the inner tube has a side opening adjacent its distal end. The side opening of the inner tube has a peripheral edge forming a second cutting edge, the side opening being in line with the side opening of the outer tube when the inner tube rotates relative to the outer tube. become. The connecting means relatively rotates the inner pipe and the outer pipe to form a seal between the inner pipe and the outer pipe. The device of the invention further comprises a rotating means connected to the inner tube for rotating the inner tube relative to the outer tube, and the inner tube being in a first rotational position, ie the outer tube. There is suction means coupled to the inner tube to introduce a substance into the inner tube when the tube opening is aligned with the inner tube opening. When the inner pipe rotates to the second rotation position, that is, when the opening of the inner pipe is aligned with the opening of the outer pipe, the first cutting edge of the outer pipe and the second cutting edge of the inner pipe. Cooperate to cut off a portion of the material in the inner tube.

In a preferred embodiment, rotation of the inner tube is accomplished by a reciprocating piston having a rack that engages a pinion mounted on the inner tube.

Further, a preferred embodiment of the present invention employs a single flexible hose that enables relative rotation between the inner pipe and the outer pipe and connects the inner pipe and the outer pipe.

The cutter probe of the present invention also has an elongated, generally tubular housing that supports and substantially houses the inner tube, the outer tube, and the rotating means. In this preferred embodiment, the housing is made up of two pieces. This preferred design simplifies the construction and simplifies the construction of the device as it only requires unitary molding. Preferably, the lightweight plastic material reduces costs and allows the manufacture of disposable devices. The preferred form of the housing is streamlined and has a protruding surface near the distal end for ease of grasping and ease of surgeon manipulation.

The cutting element of the device of the present invention has an inner tube concentrically housed in an outer tube, both tubes having a proximal end and a distal end, and the inner tube rotating relative to the outer tube. As such, each tube has a side opening adjacent its distal end. The openings are aligned at the first rotational position and when the inner tube is rotated to the second position relative to the outer tube, the peripheral edges of each opening cooperate to provide a cutting action. In a preferred embodiment, the distal end within the outer tube is slightly bent. In a preferred form, the opening structure of the cutting edges of the inner pipe automatically springs the inner cutting edges when they are spring loaded against the outer pipe and as a result rotate against the inner surface of the outer pipe. To sharpen sharply.
This preferred form also allows access of the cutting edge to its tip. This facilitates the surgeon's operation while at the same time keeping the surgeon as close to the eye wall as possible.

The rotating means used in the preferred embodiment of the invention comprises an air driven reciprocating piston having a rack therein for engaging a pinion mounted on the inner tube. The piston preferably has pneumatic seals at its ends. These seals create friction in the wall of the housing that prevents movement of the piston until sufficient air pressure to quickly lock the piston to the other restriction, thereby increasing the cutting speed of the instrument.

Further, preferably, the piston and pneumatic seal are formed of a single piece material that allows a thin and stable sealing surface (pneumatic seal) and a strong and thick portion (piston with inner rack) to be integrally molded. This configuration simplifies the manufacture and assembly of the present invention. Suitable materials for manufacturing the piston of the present invention include thermoplastic polyester elastomers such as those sold under the HYTREL name by EIDu Pout de Nemours and Co.

There are several advantages to the preferred embodiment according to the particular configuration of the invention.

Miniaturization of moving parts minimizes vibration of surgical instruments. Also, the rotational cutting action of the present invention does not pose a risk associated with vibration (such as the conventional diaphragm-driven vitreous cutter tip), and therefore does not damage the retina when the instrument is used near the posterior wall of the eye. The intentional damage can be reduced. Moreover, the rotary cutter motion of the present invention does not create the uncontrolled pumping action that limits the cutting speed of conventional diaphragm driven vitreous cutters. This is because in the present invention, axial movement does not occur between the inner tube and the outer tube that vibrate the fluid in the inner tube of the device. Another advantage of the preferred embodiment is that air pressure is utilized to positively drive the piston in both directions. This design doubles the power and greatly enhances the cutter speed of the instrument.

A preferred embodiment of the present invention employs external pneumatic means having two separate sources of pneumatic pressure connected to the instrument via two ports on the end cap of the housing unit. Compressed air sent from each port is sent to one end of a chamber (formed inside the housing) in which the piston reciprocates. In this embodiment, the end cap only forms a pneumatic seal with the chamber surrounding the reciprocating piston, but this cap holds together two identical divisions of the housing unit. The two external air pressure sources alternately supply air pressure to each of the ports to enable reciprocal movement of the piston. As the optimum cutter speed is approached, instrument vibration will decrease. This is due to the increased velocity "hum" that occurs when the piston's back-and-forth motion is no longer felt.

The present invention has a connecting means that allows relative rotational movement between the inner and outer tubes to form a seal between the inner and outer tubes. In this preferred embodiment, the connecting means is formed by a length of flexible hose having an inner diameter slightly smaller than the outer tube and slightly larger than the inner tube. The distal end of the hose suitably fits onto the proximal portion of the outer tube which holds it in place. The proximal end of the inner tube projects from the proximal end of the outer tube and the proximal end of the hose, and the proximal end of the hose is folded in a distal direction so that one end of the inner tube Engage the section to form a double layer hose.

The coupling means of the above aspect does not permit relative movement of the inner and outer tubes at the proximal or distal ends of the flexible hose. The position of each tube with respect to the hose is fixed. However, since the central portion of the flexible hose is elastic and twists when the inner tube rotates, the relative rotational movement between the inner tube and the outer tube is possible. This preferred embodiment of the coupling means is simple and reduces manufacturing costs. Furthermore, since the rotation of the inner tube is limited to a relatively small arc by the rack and pinion mechanism, the flexible hose undergoes little stress as a result of the twisting movement.

Since a suction means such as a vacuum tube is connected to the inner tube of the present invention to suck a glass substance into the inner tube, a part of the glass substance is cut and removed by suction through the inner tube. . In a preferred embodiment, the suction means is not directly connected to the rotating inner tube but is attached to the end cap of the housing. This configuration eliminates vibration of the suction tube transmitted to the surgeon's hand and stabilizes the use of the instrument.

The overall design of the preferred embodiment of the present invention minimizes the number of parts. The simplicity of this design facilitates manufacturing and the use of inexpensive materials makes the device of the present invention reasonably costable for single use.

〔Example〕

A preferred embodiment surgical instrument in accordance with the present invention comprises means for removing the vitreous from the eye during ophthalmic surgery and is represented in the preferred embodiment assembly in FIG.

The device of the present invention includes an outer tube 1, an inner tube 2, and a reciprocating air-driven piston 3 as basic elements (No. 3-5).
All) partially enclosed by the housing 4.
The housing 4 comprises one or more sides and is easily assembled. Preferably, the housing 4 has an annular nose piece on the distal end.
An end piece 23 (2) with two identical shells 17, 2 with air supply fittings 12, 13 having 20 (Figs. 1-3).
Figure), and one suction port 14 at the proximal end. Each shell 17 has a semi-circular cross-section (see FIG. 5) and when the two are assembled form the elongated body of the generally tubular housing 4. The shells 17 are connected by tapered pins 26 and holes 27, each shell 17 having a single pin 26 and a single hole 26. The two shells 17 are pressed together to urge the pin 26 into the hole 27. The maximum diameter of the pin 26 is slightly larger than the diameter of the hole 27,
Causes collision or frictional engagement. The annular nose piece 20 slides over the distal tips of the concentric tubes 1 and 2 and fits into the circumferential groove 21 at the distal end of the shell 17.

The cutting action of the above tool is to create an edge A (formed by punching a hole 5 in the end of the inner tube 2 as shown in FIGS. 9 and 10) into the opening 6 formed in the outer tube 1. By moving to. As shown in FIG. 8-10, the distal end portion of the outer tube 1 has a bent portion 7. Since the groove or hole cross section 8 is formed in the inner pipe 2, the cutting edge 5A is only slightly interference-fitted to the outer pipe 1 in the bent portion 7. This allows the self-sharpening action of the cutting edge 5A without increasing the torque driving the inner tube 2. This self-sharpening effect can also be achieved economically by simply enlarging the hole 5, so that its proximal edge projects in the proximal direction from the bend 7 of the outer tube 1. A particularly suitable material for the cutter of the present invention is a stainless steal mold 303 known as hypodermic needle steel.

4 and 5, the inner tube 2 is driven by a pinion gear 9 fixed to the inner tube 2. This gear 9 preferably engages with a rack 11 which is integrally formed with the piston 3. The piston 3 has a seal 28 at each end which contacts the wall of the chamber 25. In a preferred embodiment, the seal 28 is integrally formed with the piston 3. When the air pressure increases at the mounting portion 12, the piston 3 moves up and the hole of the gear 9 and the inner pipe 2 mounted on the gear 9 does not coincide with the opening 6 of the outer pipe 1 (Fig. 12). It is rotated to a position, whereby the glass substance sucked into the hole 5 of the inner tube 2 is cut. Releasing the pressure at the mounting portion 12 and increasing the pressure at the mounting portion 13 lowers the piston, rotates the gear 9 and the inner tube 2 attached thereto to the open position shown in FIG. Prepare to introduce glass.

The suction device of the mounting part 14 is connected to the inner tube 2 via a "0" ring 15. The "0" ring 15 is held in place by a semi-circular protrusion 16 protruding from the two-piece body 17. The protrusion 16 is also biased against the precision bore 18 during assembly so that the inner tube 2
To form precision bearings. As a result, even if the two-divided body 17 is slightly incompletely separated at the time of molding, the protrusion 16
Are always fully biased into close engagement with each other. Outer tube 1
Air leakage in the suction pipe between the inner pipe 2 and the inner pipe 2 is prevented by the seal 19 (FIGS. 3, 4 and 7). The seal 19 is formed by a flexible hose having an inner diameter slightly smaller than the outer diameter of the outer tube 1 and larger than the outer diameter of the inner tube 2. The proximal end of this hose is rewound to reduce the inner diameter and
Although sealed above, the center of the hose is retractable. Since this structure does not perform relative sliding, it has low torque and durability.

Assembly is performed as follows. Piston 3 first shell 17
Assemble to The outer tube 1 and the inner tube 2 are assembled and engaged with the seal 19. Insert the inner tube and outer tube assembly with gear 9 and seal 19 in place (see FIG. 4) into the piston opening and engage the pinion gear 9 with the rack 11 (FIG. 5),
And the second shell 17 is assembled into the first divided body 17. Nose piece 20
Is inserted into the holding groove 21 which is a part of the divided body 17. The outer tube 1 is positioned so that the inner tube 2 is adjacent to the distal end of the outer tube 1, and then the outer tube 1 is glued to the nose piece 20 at 22 locations, for example with a drop of solvent.

The end cap 23 containing the mounts 12, 13 and 14 has an air inlet derived from the mounts 12 and 13,
And the two shells 17 perpendicular to the assembly of the inner pipe and the outer pipe.
2 tapered protrusions along an axis perpendicular to the plane formed on the
Having 24. The protrusions 24 are spaced apart and the two split bodies 17
Are mutually pulled and airtightly coupled. With mounting part 12
13 offsets on the protrusion 24 to bring the tubing connected to the fitting closer to the centerline of the instrument, thereby facilitating control of the instrument. For the final adjustment, for the cutter open position in FIG. 11, for example, one mounting portion 13 is selected,
Send air pressure to move the piston 3 to the opposite end of the chamber 25,
Then, the nose piece 20 to which the outer tube 1 is adhered is rotated until the cutter is completely opened. The cutter is closed as shown in FIG. 12 by releasing the pressure at the mounting portion 13 and applying pressure to the mounting portion 12 to move it to the other end of the piston chamber 3 and the chamber 25.

At this time, the device of the invention is fully operational and inspected. End caps if proven suitable for use
23 and the nose piece 20 can be semi-permanently bonded to the split body 17. If a defect is found during inspection, the device can be easily disassembled and repaired.

From the above description and examples, it is apparent that the objects of the present invention can be achieved. It will be apparent to those skilled in the art that the above examples are only one aspect of the invention and that other aspects and modifications are possible. Such modifications should be determined based on the spirit of the invention and the scope of the claims.

[Brief description of drawings]

1 is a plan view of an assembled vitreous cutter probe according to the present invention, FIG. 2 is a plan view of an end cap, and FIG. 3 is an assembled vitreous cutter probe taken along line 3-3 of FIG. 4 is a sectional view of the assembled vitreous cutter probe taken along line 4-4 in FIG. 2, and FIG. 5 is an assembled vitreous cutter taken along line 5-5 in FIG. 6 is a sectional view of the probe, FIG. 6 is a partial sectional view of the proximal end of the end cap and the inner tube, FIG. 7 is a sectional view of the inner tube and the outer tube concentrically connected by an elastic hose, and FIG. FIG. 9 is a plan view of an outer tube concentric with the distal end of the inner tube, and FIG. 9 is a partial cross-sectional view of the outer tube concentric with the distal end of the inner tube, wherein the inner tube opening is the outer tube opening. FIG. 10 is a partial cross-sectional view of the outer tube concentric with the distal end of the inner tube in the closed position where the inner tube opening is not aligned with the outer tube opening, FIG. Ninth view of a distal end portion and a concentric inner tube of the outer tube the tube opening is in the open position in the outer tube opening and a straight line 11
-11 is a cross-sectional view taken along line -11, and Figure 12 shows 12 of Figure 10 of the outer tube concentric with the distal end of the inner tube in the closed position where the inner tube opening is not aligned with the outer tube opening.
FIG. 12 is a cross-sectional view taken along line -12. 1 ... Outer tube, 2 ... Inner tube, 3 ... Piston, 4 ... Housing, 5 ... Inner tube hole (side opening), 5A ... Edge (cutting edge), 6 ... Outer tube Opening part (side opening part), 7 ... bent part, 9 ... gear, 11 ... rack, 1
2,13 …… Air supply fitting (mounting part), 14 …… Suction port (mounting part), 17 …… Shell (split body), 19 ……
Seal (seal means), 23 ... end cap, 25 ... chamber,
28 …… Seal.

Claims (11)

[Claims] 1. An outer tube having a proximal end and a closed distal end and having a side opening adjacent to the distal end, the side opening having a first cutting edge. (B) an inner tube that is concentrically housed in the outer tube and that rotates relative to the outer tube, the inner tube having a proximal end and a distal end, and A portion extending proximally from the proximal end of the tube, the distal end of the inner tube is adjacent to the distal end of the outer tube, and the inner tube is A side opening is provided adjacent to the distal end, and the side opening has a peripheral edge forming a second cutting edge, and (c) the inner tube and the outer tube are relatively rotated to each other. Means for connecting the tube to the outer tube, (d) means connected to the inner tube for rotating the inner tube relative to the outer tube, and And (e) suction means connected to the inner pipe for introducing a substance into the inner pipe when the outer pipe opening is aligned with the inner pipe opening, and the inner pipe opening is When the inner pipe is in the first rotation position, it is in line with the outer pipe opening, and in the second rotation position, it is not in line with the outer pipe opening,
Thereby, when the inner pipe rotates from the first rotation position to the second rotation position, the first cutting edge and the second cutting edge cooperate to cut a part of the substance in the inner pipe. A surgical instrument characterized by: 2. The surgical instrument of claim 1 having an elongated generally tubular housing that supports and substantially houses the outer tube, the inner tube, and the rotating means coupled to the inner tube. 3. The surgical instrument of claim 1, wherein the means for rotating the inner tube comprises a reciprocating member for alternately rotating the inner tube between the first rotational position and the second rotational position. 4. The surgical instrument of claim 3, wherein the inner tube rotating means comprises a rack and a pinion. 5. The surgical instrument of claim 4, wherein the pinion is secured to the inner tube. 6. The surgical instrument of claim 4, wherein the rack is installed within the reciprocating member. 7. The surgical instrument of claim 6, wherein the reciprocating member comprises a pneumatically driven pinion. 8. The surgical instrument of claim 7, wherein the piston has sealing means located at each end thereof. 9. The surgical instrument of claim 6 wherein said first and second pneumatic means comprise first and second external supply means, said supply means comprising intermittent pneumatic pressure which creates a reciprocating motion within said piston. . 10. The connecting means comprises an annular member having a proximal end and a distal end, wherein the proximal end of the outer tube and a portion of the inner tube are in close engagement with the annular member. The surgical instrument of claim 1, wherein: 11. The annular member comprises a single flexible hose having a diameter smaller than the outer tube and larger than the inner tube, the proximal portion of the annular member being distally folded. The surgical instrument of claim 9, forming a bilayer of the hose that engages a portion of the inner tube.