WO2000048540A1

WO2000048540A1 - Surgical knife - capsulotome

Info

Publication number: WO2000048540A1
Application number: PCT/GR2000/000007
Authority: WO
Inventors: Dionissios Christopoulos
Original assignee: Dionissios Christopoulos
Priority date: 1999-02-17
Filing date: 2000-02-16
Publication date: 2000-08-24
Also published as: CA2328715A1; EP1071387A1; AU2566200A; GR1003307B

Abstract

Surgical knife which can be used in cataract operations and especially in cutting one part of the anterior capsule. The capsulotome is a circular (round) blade (fig. 3 β) that has the characteristic of being closed and put in the cylinder (26) (fig. 3a). The knife's blade (28) is put inside the cylinder (26) closed because it must firsly pass through a small diameter tunnel before entering the anterior chamber. When the cylinder (26) is entering the anterior chamber, the knife (28) is coming out of the cylinder (26) because of the movement of the bolt (22) and with the help of the antidiametrical sheets (24) it takes a circular (round) shape (fig. 7) cutting the membrane (32) of the anterior capsule circularily just with a simple touch. For coming out of the anterior chamber, the knife (28) is being closed, it is put again in the inner part of the cylinder (26) and comes out of the small tunnel. The knife's diameters vary from 3,5 mm to 9 mm, increasing for half a millimeter, that's why there are twelve different capsulotomesto fit with each diameter. In this way we can choose the diameter of the knife (28) according to the diameter of the membrane (32) that we want to cut. The external diameter of the cylinder (26) can be constructed from 2 mm to 3 mm in order the cylinder (26) to be able to enter in a small tunnel 3,2 mm or even smaller.

Description

SURGICAL KNIFE - CAPSULOTOME

The invention is talking about a surgical knife which can be used in the cataract operation in ECCE or PHACO and it is convinient for the creation of the necessary cut of a part of the anterior capsule which is a membrane that covers the front part of the lense.

All the technics until today are called capsulorhexis and are based either on making many succesive ray - like cuts 360° with a bended needle for the removal of the central part of the membrane of the anterior capsule leaving the rest untouched, or on a combination of ray - like cuts and breaking of the capsule with a handle. The handle catches an edge of the capsule and causes it's rift by pulling it, trying to make the cut as circular as it can be done.

In fact, you can never succeed in making the lips of the cut absolutely circular, because it will be either tooth - like or some diameter of the cut will be out of it' s place or some extra rifts will be done in the rest of the capsule with serious concequences in order nets or the cut will be smaller than the desired diameter and as a result more incisions will have to be made damaging the rest of the membrane.

Generally, the issue in this stage of the operation is to remove the anterior capsule as circular and simetrical as you can, to make the incision as central as you can in relation with the lense and the iris, not to have abnormalities in the lips of the incision that can cause more rifts in the rest of the membrane, witch must be kept untouched.

All the above technics for the removal of this part of the anterior capsule are based on its pulling not its cutting. The pulling and the power which are used have an influence in all the other nets which damaging concequences, like the capsule contraction syndrome that is characterized with exaggarated reduction in anterior capsulotomy and capsular bag diameter and it is relatively frequent with capsulorhexis in very short time after the operation, and also blur and fibber in the edges of the capsulorhexis.

The previous technics take a lot of time and when there are difficulties in the removal of the membrane the time is more than double. Moreover, the previous technics do not promise exactly the edges of the incision, nor the normality of the lips of the incision, nor the shape or the diameter of the rest of the membrane. The capsulotome is consisted of a probe (30) which has a button (20) (fig 1) or a screw (21) (fig 2), a bolt (22) which is connected with the button (20) or the screw (21) and in the lower part (25) of the probe (30) there is a cylinder (26) which in its inner part it has two latteral guides (27) on which a knife (28) is put, that is consisted from a ring (23), a basic blade of the knife (28) which ends to the cutting blade (31).

This knife (28) of the capsulotome is circular blade (fig 3β) that has the characteristic to close and can be put in the cylinder (26) ( fig 3a). The knife's blade (28) is put closed in the cylinder (26), because the cylinder (26) together with the blade (28) must pass firstly through a small - diameter tunnel before enters the anterior chamber, as the cylinder (26) enters the anterior chamber, the knife (28) is coming out of the cylinder (26) because of the move of the bolt (22) and with the help of antidiametrical sheets (24) it takes circular shape (round) (fig 7) cutting the membrane (32) of anterior capsule circular. In order to come out of the anterior chamber the knife (28) closes, enters the cylinder (26) and is put on the later guides (27) and in this way it comes out of the tunnel.

The diameters of the knife (28) vary from 3,5 mm to 9 mm incressing for a half more millimeter, therefore there are twelve different knives

(capsulotomes) to fit them. In this way we are able to choose the diameter of the knife (28) according to the diameter of the membrane

(32) we want to cut.

In a clear part of the twelve capsulotomes (30) the millimeters of each blade of the knife (28) are written that each capsulotome has in the inner part of the cylinder (26). The cylinder (26) of the capsulotome (30) is made in different diameter so as to able to pass through a tunnel of 3,2 mm diameter or over smaller, that is why the external diameter of the cylinder (26) varies from 2mm to 3 mm. The length of the cylinder (26) is about 15mm.

The cylinder (26) and the antidiametrical sheets (24) are made either of plastic or of metal or any other material.

They are constructed capsulotomes that in the ring (23) of the knife they have two antidiametrical protuberances (33) (fig 5), so as the knife can be closed easier and enters the cylinder (26) (fig 5a) when the material of construction of the ring (23) and the blade of the knife (28) is hard and doesn't close easily.

They are constructed capsulotome that make incision of membrane in oval shape (fig 8) this is made by increasing the centrifugal powers in the antidiametrical sheets (24) in the exact spots that are connected with the ring (23).

The lateral guides (27) protect the knife's blade (28) from coming into touch with the lower part of the cylinder (26), so as not to harm the cutting blade (31). The lateral guides (27) together with the antidiametrical sheets (24) and the bolt (22) guarantee the normal and steady in and out of the knife (28). The capsulotome is a renovation in the way of cutting the membrane of the anterior capsule, it enables anybody to make a circular cut of the membrane with normal and fixed edges without tooth - like edges and with no harm of the rest of the membrane which remains and must be untouched, or even of the beside nets, because with a simple touch it cuts the membrane of the anterior capsule. In this way you can avoid the capsule contraction syndrom that is characterized by exaggerated reduction of the diameter of the capsulorhexis in a short time after the operation, together with ring - like blur and fibber in the edges of the capsulorhexis. Moreover, it has the advantage of choosing the diameter of the membrane we want to cut. It must be reported here the great utility of capsulotomes so that we can choose the millimeters of the diameter we want to cut, because there are special occasions in every eye that is about to take an operation, that is to say the diameter of the membrane that the surgeon has to remove is not always the same, but varies from eye to eye. In a clear part of the probe (30) the millimetres of the cutting blade (31) that each capsulotome has in the inner part of the cylinder (26), are written.

For each diameter there is separate capsulotome. The fact that the capsulotome must enter in the eye by a small diametre's tunnel is succeeded with the construction of a knife (28) that closes and is kept in the inner part of the cylinder (26). The movement of the bolt (22) downwards so as the blade of the knife (28) will come out is done either with a button (20) (fig 1) or with the rotation of a screw (21) (fig 2) and it is controlled, because in any stage of the movement of the bolt (22), it may stop and turn back to the starting position. The button (20) may be put in any place on the probe (30) from the upper edge till 3 cm away of this lower edge.

The screw (21) may be put in the upper edge of the probe (30) which by turning around at 90° it moves the bolt (22) downwards. A very important advantage is the elimination of time that is required for the execution of this task. It has been calculated in 2 to 3 seconds.

Fig 1. The front part of the capsulotome which is consisted of a probe (30), a button (20), a bolt (22) and a cylinder (26) which is his inner part concludes two antidiametrical sheets and the blade of the knife. Fig la. The capsulotome with the button (20) as it can be seen from beside.

Fig 2. The front part of the capsulotome where the button has been replaced by a screw (21) it is consisted of a probe (30), screw (21), bolt

(22) and, in lower part (25), of the cylinder with the two antidiametrical sheets and the blade of the knife inside it.

Fig 3. The cylinder (26) in horizontal cut in bigger size with the blade of the knife closed and put on the lateral guides (27). It is consisted of a button (20) which is connected with the bolt (22), the cylinder (26) which includes the bolt (22) that is put on two lateral guides (27) the antidiametrical sheets (24) which are connected with the bolt (22) and the ring (23) of the knife, the blade of the knife (28) which ends to the cutting blade (31).

Fig 3β. The cylinder (26) as it seems from beside and the knife (28) out of the cylinder (26) which has a circular shape. In the fig we can see the cylinder (26), the bolt (22) which is put on two lateral guides (27), the two antidiametrical sheets (24) connected in one edge with the bolt (22) and in the other with the ring (23) of the knife. The inner perimetre of the ring (23) is going downwards forming the blade of the knife (28) which ends in the cutting blade (31).

Fig 3a. The cylinder (26) in horizontal cut as it has been described in fig 3 is consisted of a screw (21) for the movement of the bolt (22). In the vertical cut, you can see the ring (23) with the blade of the knife (28) which is put on the two lateral guides (27). The cutting blade (31) is protected by the lateral guides (27) so as not to come in touch with the inner part of the cylinder (26) and harm the cutting surface.

Fig 4. The cylinder (26) in horizontal cut with the blade of the knife out of it in circular shape. We can see the button (20) that makes the movement of the bolt (22). The bolt (22) with this movement on the lateral guides (27) reaches till the end of the cylinder (26) pushing the antidiametrical sheets (24) and the knife with its ring (23) out of the cylinder (26) taking circular shape.

Fig 5. The cylinder (26) as it has been described in fig 4, but with the difference that the ring (23) of the knife has two antidiametrical protuberances (33) that help the blade of the knife to close in case that the material of the blade of the knife is hard. Fig 5a. The cylinder in horizontal cut. We can see the knife of fig 5 with the antidiametrical protuberances (33) closed in the cylinder (26).

Fig 6. The cylinder (26) in horizontal cut with the antidiametrical sheets (24) constructed incorporated in the ring (23) of the knife instead of being connected antidiametrically from beside, as it has been described in fig 3.

Fig 6a. The cylinder (26) as it is described in fig 6 with the knife closed in the cylinder (26) and the ring (23) of the knife which is incorporated in the antidiametrical sheets (24).

Fig 7. You can see the eyeball and the cylinder (26) of the capsulotome in vertical cut. The cylinder (26) has been inserted in the anterior chamber through a small diameter tunnel, the knife (28) is out of the cylinder taking a circular shape, with the cutting blade (31) ready to cut the membrane (32) of the anterior capsule. The antidiametrical sheets (24) are connected with the ring (23) of the knife (28) and with the bolt (22) which is put on the lateral guides (27) of the cylinder (26).

Fig 8. The cylinder (26) of the capsulotome in horizontal cut. You can see a version of the knife, which instead of being circular, it has an oval shape increasing the centrifugal powers in the antidiametrical sheets (24).

The capsulotome is a surgical knife which is consisted of cylinder (26) where in its inner part there is the knife (28) a bolt (22), a probe (30) and either of a button (20) (fig 1) or a screw (21) (fig 2). In the inner part of the cylinder (26) there are two lateral guides (27) on which the antidiametrical sheets (24) are put, one part of the ring (23) of the knife and the bolt (22) (fig 3). The two lateral guides (27) are adjusted in the whole length of the cylinder (26) making sure of the normal in and out of the blade of the knife (28), her stability and also protect the cutting blade (31) from coming into touch with the lower part of the cylinder (26), so as not to be harmed. The antidiametrical sheets (24) in their one edge (29) are connected with the bolt (22) and in other are connected with the ring (23) either from beside antidiametrically (fig 3) or with the incorporation of the sheets (24) and the ring (23) antidiametrically (fig 6). The cylinder (26), the sheets (24) and the blade of the knife (28) are constructed either from plastic or metal or any other material. The inner perimeter of the ring (23) speads downwards forming the basic blade of the knife (28) which ends to the cutting blade (31) (fig. 3). The external perimeter of the ring (23) is round so as not to harm all the beside nets when the surgical knife is in the anterior chamber, (fig 7).

The ring (23) the blade of the knife (28) and the cutting blade (31) is a one and only body, and all together they form the knife of the capsulotome (fig. 3β), which is a circular (round) blade (fig 4) that has the ability to close taking oval shape and is put in the cylinder (26) (fig.3a). The diameters of the knife (28) vary from 3,5 mm to 9mm, increasing for half a millimeter, that is why there are twelve different knives (capsulotomes) to fit with these diameters. In this way we can choose the diameter of the knife (28) according to the diametre of the membrane (32) that we want to cut. Capsulotomes are constructed where the bolt (22) is connected either with a button (20) or a screw (21). The place of the button (20) can be in any part of the probe (30), from the upper edge till three centimeters away of the lower edge. The position of the screw (21) it can be in the upper edge of the probe (30), turning around 90° and moves the bolt (22) downwards, which pushes the antidiametrical sheets (24) and knife (28) to come out of the cylinder (26).

Claims

1. Surgical knife (capsulotome) which can be used in cataract operation in ECCE or PHACO, convinient for the formation of the neseccary

5 incision of a part of the anterior capsule, which is a membrane (32) that covers the front part of the lense and it is characterized by the fact that it is consisted of a probe (30), which has either a button (20) or a screw (21), a bolt (22) which is connected with the button (20) or a screw (21) and in the lower part (25) of the probe of a cylinder (26),

10 where in its inner part the knife (28) is put, which is consisted of a ring

(23), the basic blade of the knife (28) that is a continuation of the inner perimeter of the ring (23) downwards and ends to the cutting blade (31), the ring (23) is connected with two antidiametrical sheets (24) which, in their turn, are connected with the bolt (22) the

15 antidiametrical sheets (24) and the bolt (22) are put on two lateral guides (27) which they are in the whole length of the cylinder (26). The ring (23) has a round external perimeter so as not to harm beside nets when the surgical knife is in the anterior chamber, (fig 7).

20 2. Surgical knife (capsulotome), according to claim 1 is characterized by the fact that it has a circular (round) shape (fig. 4) to cut the membrane (32) circularily with normal and fixed edges, its diameters vary from 3,5 mm to 9mm, increasing up to a half milimeter that is why there are twelve different knives (capsulotomes) to fit these diameters. In this

25 way we can choose the diameter of the knife (28) according to the diameter of the membrane (32) that we want to cut. There is even a knife that in its ring (23) has two antidiametrical protuberance (33) that help the blade of the knife (28) to close and enter in the cylinder (26) if the material of the construction of the ring (23) is hard.

30

3. Surgical knife (capsulotome), according to claims 1,2 is characterized from the fact that when it comes out of the cylinder (26) it takes a circular shape (fig. 4) and when it enters the cylinder (26) it closes, taking an oval shape, (fig. 3), because the diameter of the cylinder (26)

- . is smaller than the diameter of the knife (28). The cylinder (26) of the capsulotome (30) can be constructed in several diameters so as to be able to enter a tunnel 3,2 mm or even smaller, that is why the external diameter of the cylinder is made from 2 mm till 3mm. The length of the cylinder (26) is about 15mm. The cylinder (26) is made of plastic,

.„ or metal or any other material.

4. Surgical knife (capsulotome), according to claims 1,2,3 is characterized by the fact that the cylinder (26) is entering the anterior chamber through a small diameter tunnel, giving the knife (28) which is kept closed in the cylinder (26), the ability to enter the anterior chamber. The knife (28) is coming out of the cylinder (26) taking a circular shape (fig. 4) and cutting the central part of the membrane (32) circularily and in the desired diameter. In order to come out of the anterior chamber, the circular knife (28)with the ring (23) close with the help of the bolt (22) and the antidiametrical sheets (24), they enter the cylinder (26) taking an oval shape (fig 3 )and in this way the cylinder (26) the knife(28), the ring (23) and the antidiametrical sheets (24) come out of the tunnel.

5. Surgical knife (capsulotome), according to claims 1,2,3,4 is characterized by the fact that the cylinder (26) has two lateral guides (27) in its whole length where two antidiametrical sheets (24) and the bolt (22) are adjusted making the normal and steady entrance and exit of the knife (28) easier.

6. Surgical knife (capsulotome), according to claims 1,2,3,4,5 is characterized by the fact that the antidiametrical sheets (24) are connected with the ring (23) either antidiametrically from beside or with incorporation of the sheets (24) and the ring (23) also antidiametrically (fig 6). The sheets (24) are constructed either of plastic, or metal or any other material.

7. Surgical knife (capsulotome), according to claims 1,2,3,4,5,6 is characterized by the fact that the antidiametrical sheets (24) give the knife (28) circular shape when it is coming out of the cylinder (26) and together with the bolt (22), they help to close the knife and put it in the cylinder (26). A capsulotome is been constructed that gives it an oval shape and this is succeeded by increasing the centrigugal powers in the two antidiametrical sheets (24) in the parts which they are connected with the ring (23).

8. Surgical knife (capsulotome), according to claims 1,2,3,4,5,6 is characterized by the fact that the antidiametrical sheets (24) together with the lateral guides (27) protect the blade of the knife (28), so as to avoid the touch with the inner part of the cylinder (26) and not harm the cutting blade (31).

9. Surgical knife (capsulotome), according to claims 1,2,3,4,5,6,7 is characterized by the fact that the blade of the knife (28), the ring (23) and the antidiametrical sheets (24) that are connected with the bolt

(22) moving them downwards, they come out of the cylinder (26). The movement of the bolt (22) is done either by a button (20) moving it downwards, or by a screw (21) that turning it around it pushes the bolt (22) and this, in its turn, pushes the antidiametrical sheets (24), which push the ring (23) and the blade of the knife (28) to come out of the cylinder (26).