Ophthalmic Surgical Instrument

There are many types and designs of instruments which have been developed and used in ophthalmic surgery. Such devices may be inserted into the eye and used to perform cutting or surgical procedures.

An example of such a device is depicted in U.S. Pat. No. 3,945,375 entitled Rotatable Surgical Instrument which issued on Mar. 23, 1976 to A. Banko. In this instrument, the cutting member operates like a drill bit. Tissue is drawn inside as the cutter rotates.

Other patents such as U.S. Pat. No. 4,061,146 entitled Tissue Macerating Instrument issued on Dec. 6, 1967 to E. F. Baehr, et al. This patent shows a tool used in a cataract operation. The instrument employs a rotating cutter which is again inserted into the eye to perform cataract surgery.

Other patents such as U.S. Pat. No. 4,167,943, U.S. Pat. No. 4,200,106 and U.S. Pat. No. 4,236,519 depict various devices for performing eye surgery. These devices relate to cutters and other instruments as punches for operating on or in association with the cornea or other parts of the eye.

As indicated above, such instruments are extremely useful to the surgeon and for example, they have substantially reduced the operating time and therefore provide for faster patient recovery.

In any event, there is a fairly common operation which is performed known as a peripheral iridectomy. In such an operation, an aperture or hole is made by the surgeon in the iris of the eye. This hole is made to alleviate pressure and to further be used in cataract procedures. Essentially, the irridectomy is a fairly common operation and is performed many times during the course of a year in this country and elsewhere. The operation as presently performed requires that the surgeon cut through the cornea of the eye to gain access to the iris and thereafter cut a hole or remove a portion of the iris, thus completing the iridectomy. As one can ascertain, the cutting of the eye, as well as the attendant surgery is relatively complicated and time consuming and further involves a fairly extensive recovery period for the patient.

It is therefore an object of the present invention to provide a surgical instrument which can be employed by the surgeon to perform an iridectomy in a simple procedure thus eliminating many of the disadvantages as present in the prior art.

A surgical instrument particularly adaptable for performing a peripheral iridectomy comprising a hollow tubular member having a pointed end portion with a front opening in said pointed end portion, movable tissue grasping means located in the hollow of said tubular member and operative when moved in a first direction to pass through said opening to grasp tissue and when moved in a second direction to draw said grasped tissue through said opening into said hollow of said tubular member, and cutting means located in the hollow of said tubular member and operative to cut said tissue as drawn into said hollow.

FIG. 1 is a side elevational view of a surgical instrument according to this invention.

FIG. 2 is a top plan view partially in cross-section of the surgical instrument.

FIG. 3 is a side plan view of a grasping mechanism used in this invention.

FIG. 4 is a front view of a cutter mechanism.

FIG. 5 is a top view of the cutter mechanism.

FIG. 6 is a side view of an actuator used for operating the cutter mechanism.

FIG. 7 is a cross-sectional view of an eye useful in explaning the iridectomy procedure.

Referring to FIG. 1, the instrument 10 includes a front portion 11 which is a tapered needle type projection capable of penetrating and being inserted into the tissue of the eye. The needle portion 11 is contiguous with the body portion 12 which may be a cylindrical or other configuration.

FIG. 2 depicts a top view of the instrument 10 shown in FIG. 1. The entire body including the needle portion 11 and the cylindrical body portion 12 may be integrally formed from glass, steel or a suitable plastic. Essentially, the instrument 10 has an internal hollow. The needle or tip has an opening 12 which may be about 1 to 2 mm in diameter. Located within the housing is a tine like grasping mechanism 14. The mechanism 14 consists of a first tine 15 integrally formed with a second tine 16, as more clearly shown in FIG. 3. The tine 15 is of an arcuate configuration having a top apex which abuts against the inside wall of the inner housing 12. The tines 15 and 16 are prong like members fabricated from a spring steel or other spring like material and act as grasping prongs. The tine 16 is relatively flat or horizontal. Both tines 15 and 16 may be integrally formed from a single strand of spring steel or another material which has spring like capabilities. A loop of material 17 is formed between the tines 15 and 16 to enhance the spring like characteristics of the structure.

As will be explained, the tines 15 and 16 act as a grasping instrument whose operation is much like that of a forceps. Coupled to the loop 17 is a shaft 18 which is directed through the body 12 and terminates outside the body in a plunger 19. The shaft is supported concentric with the body 12 by means of suitable supporting ribs as 20 and 21. Mechanisms for supporting shafts within cylindrical members are well-known.

As seen from FIG. 1 and as will be further explained, located adjacent the needle portion 11 and within the hollow of the housing is a cutting mechanism 25. The cutting mechanism 25 consists of two cutter blades which are operated by the surgeon pushing two prongs as 26 and 27, which prongs are located within a slot on either side of the housing. As will be explained, a surgeon, by pushing the prongs forward can activate the cutter.

As seen in FIG. 2, located above the tine 15 is a slot 30. The slot 30 is directed towards the tip of the needle and is an extremely narrow slot but of a width sufficient to allow the tine 15 to spring upwardly as the plunger 19 is pushed by the surgeon, as will be explained.

Shown in FIG. 2, is a top view of the cutter mechanism 25. The view in FIG. 2 is in a partial section for a complete understanding. The cutter 25 includes two cutting blades 32 and 33 which are positioned in a slot or groove 34 located about periphery of the housing.

As seen in FIG. 4, the blades or cutters 32 and 33 are planar members and are fabricated from a steel or other material and are extremely sharp. The blades are positioned in grooves as 34 and are spring biased by means of springs 35 and 36 which are coupled to the inner walls of the housing through a slot 37 located in a cylindrical tapered push member 40 which is further shown in FIGS. 5 and 6.

The member 40 as also shown in FIG. 2, has an internal taper which abuts against the outer edges of the cutter blades 32 and 33. The member 40 is contiguous with an inner cylindrical member 41 which is secured to the tabs 26 and 27. A greater understanding of the operation of the device will now be had by describing the surgical procedure.

Referring to FIG. 7, there is shown a cross-section of a typical eye 50. The structure of the eye is very well-known and reference is made to Gray's Anatomy by Crown Publishers, Inc. (1977). The eye has a front clear portion 51, known as the cornea. The iris of the eye 52 is located behind the cornea and separated from the cornea by the anterior chamber 53. The lense 54 is positioned behind the iris.

In using the instrument to perform an iridectomy the needle portion of the instrument is inserted through the cornea into the region of the iris. The surgeon of course has the use of an optical microscope and other devices which allows him to implace the needle portion in the exact position. When the needle portion is properly positioned with respect to the iris, the surgeon then depresses plunger 19 which moves the shaft 18 of FIG. 1 in the direction of the arrow. As soon as the apex of the upper tine 15 underlies the slot 30, the upper tine springs upwardly as shown in the dashed configuration of FIG. 1. The surgeon then positions the tines so that they overlie a portion of the tissue of the iris. The plunger is now moved by the surgeon in the opposite direction. Accordingly, as the tines are moved back into the housing; the tissue of the iris is grasped by the tines and pulled into the aperture 12 of the needle. As the surgeon continues to pull the tissue via the tines, the tissue enters the aperture 60 which is formed between the cutting blades 32 and 33. This is shown in FIG. 5. The surgeon then pulls a given amount of tissue through the aperture 60 so that the tissue of the iris is located between the blades 32 and 33. When the correct amount of tissue is present, the surgeon then pushes the projections 26 and 27 which causes the tapered member 40 to push the blades 33 and 34 into the tissue to thereby cut the same. The cut tissue remains inside the housing. The tissue of the iris which was not cut will spring back through the aperture of the needle into position. It is noted that the tissue of the iris is extremely flexible and pliable and essentially has good elasticity.

From the above description it is now clear that the iridectomy can be performed by the surgeon utilizing the simple structure depicted above. The mechanism described has the grasping and cutting means located within the instrument and hence the entire operation can be performed through the relatively small aperture which is formed in the eye during needle insertion. It is of course understood that there are alternative ways of creating a grasping mechanism, as well as a cutting mechanism which will operate to perform the surgical procedure. All such modifications and alterations are deemed to be encompassed within the spirit and scope as set forth in the claims appended hereto.