FIELD OF INVENTION

The present invention relates to a surgical device for use in achieving haemostasis or ligation of a tissue during surgery, and more particularly to the surgical device for use in achieving haemostasis or ligation of a tissue during surgery, especially during laparoscopic or endoscopic surgery.

BACKGROUND OF THE INVENTION

Advancements in technology have allowed laparoscopic surgery to expand into more complicated procedures. Haemostasis of vessels supplying blood to the organs is required during many such surgeries. Currently, some clip applying devices are used for haemostasis of blood vessels. Alternatively single, inert, nonreactive titanium clips are applied on a vessel with a reusable stainless steel laparoscopic clip applier instruments. The clip appliers can also be used in a disposable or automatic forms. The clips can be applied efficiently and quickly for individual bleeding sites where the application of any other form of energy source would jeopardize adjacent structures. Furthermore, clips physically close the blood vessels and hence can be applied even on very large vessels, where electro-cautery hemostasis does not work well. However, the surgical devices required for applying a staple or clip for haemostasis of blood vessel are large in size and sometimes difficult to use. The cross sectional diameter of these devices is anywhere between 5 mm to 10 mm, with typical instruments being around 8 mm in diameter The staple or clip may or may not be biodegradable and may be retained in the body of a patient. On the other hand, the vessels supplying blood can also be tied by bio-absorbable/dissolvable sutures. Traditionally, tying up blood vessels by sutures was the primary method used for haemostasis of blood vessels. This method of tying with sutures was a standard practice and was very effective in open surgeries, where the access to the surgical site was available. However, there are no laparoscopic surgical devices or even regular surgical devices available which can easily tie the sutures around blood vessels for haemostasis. By current methods, such a knot would have to be tied manually, using one or more additional graspers, which can be time consuming and very difficult, especially in laparoscopic surgery.

All of the methods mentioned above require the use of large instruments, between 5-10 mm in diameter and accordingly require the creation of correspondingly large incisions in the skin along with trocars of the appropriate size. Such incisions result in pain, longer hospital stays, more intense post-operative medications as well as a near-permanent scar at the site of the incision. On top of this, there are medical risks such as risks of hernias, infections and other issues at the trocar sites. Accordingly, there exists a need to provide a surgical device for ligation of tissue which overcomes abovementioned drawbacks. OBJECTS OF THE INVENTION

An object of the present invention is to provide a device for ligation of tissue which is easy to operate.

Another object of the present invention is to provide locking of a tissue with a fastener which is absorbable.

Yet another object of the invention is to provide a device that achieves the ligation of the tissue or blood vessel during surgery, with an incision less than 2 mm in diameter.

Yet another object of the invention is to provide for a device that enables the use of a very small incision in the skin, but due to the two or three dimensional curvature of the instrument, provides for a larger effective area to carry out useful functions.

Summary of the invention

Accordingly, the present invention provides a surgical device for ligation of a tissue during surgery. The surgical device comprises an elongated hollow rigid member adapted to have a curved shape at its distal end, wherein the distal end is a shearing surface at the curved position. The surgical device further comprises an opening in the form of a hole configured at proximal end of the curved shape and a thin rigid elongated member capable of moving freely through the hole of the elongated hollow rigid member. The thin rigid elongated member includes a miniature hook at its distal end. The surgical device furthermore includes a slit adapted on inner periphery of the curved shape of the elongated hollow rigid member. Moreover, the surgical device comprises a thin elongated flexible member adapted to have a loop at its one end, and other end is free end, wherein the loop is maintained at the distal end of the curved shape and the free end passes along the curved shape, and coming out the first hole, whereby the free end is twisted in the form of a knot on the elongated portion of the elongated hollow rigid member .

Brief description of the drawings

FIG. 1 illustrates the general use case of such surgical device for ligation of a tissue during surgery.

FIG. 2a, 2b, 2c demonstrate the general principle where a curved needle in two or three dimensions achieves a larger effective area to perform useful functions with, while at the same time restricting the incision size to the cross sectional area of the needle, which is exceedingly smaller compared to the larger effective area subtended by the curvature.

Fig 3 shows an overall construction of a generic instrument based on this principle, wherein FIG. 3a, 3b, 3c demonstrate some embodiments of this principle where the larger area subtended by a curved elongated member is used for certain useful functions (shearing function in FIG. 3a, grasping function in FIG. 3b and a vessel ligation device in FIG. 3c)

Figures 4 to 9 show various steps of use of an embodiment of a surgical device for ligation of a tissue during a surgery, in accordance with the present invention.

Detailed description of the invention

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in brackets in the following description.

Referring now to figures 1-9, there is shown a surgical device (100) (hereinafter 'the device (100)') for ligation of a tissue during a surgery, in accordance with the present invention.

The device (100) comprises an elongated hollow rigid member (10). The elongated hollow rigid member (10) is adapted to have a curved shape (12) at its distal end. The elongated rigid member (10) has a shearing surface at its tip akin to an elongated surgical needle as depicted in FIG. 2a. In one embodiment, the curved shape (12) of the elongated hollow rigid member (10) is bent in a 2 dimensional space as shown in FIG 2b. In another embodiment, the curved shape (12) of the elongated hollow rigid member (10) is obtained by bending the hollow elongated tube (10) in a 3 dimensional space as shown in FIG. 2C. Specifically, the cross sections of the elongated hollow rigid member (10) and the curved shape (12) of all embodiments are same and can be inserted into the inflated abdomen with an incision of same size.

In a preferred embodiment which is shown in Fig. 3-C, the curved shape (12) of the elongated hollow rigid member (10) extends in such a way that the distal end of the curved shape (12) is approximately collinear with the axis of the straight portion of the elongated hollow rigid member (10). In another embodiment, the curved shape (12) extends such that it is tangential to the axis of the straight portion of the elongated hollow rigid member (10) at the beginning.

The elongated hollow rigid member (10) includes an opening in the form of a hole (14) configured at proximal end of the curved shape (12) of the elongated hollow rigid member (10) where the curve begins. The elongated hollow rigid member (10) allows passage of a thin rigid elongated member (16) through the hole (14) as shown in FIG 3C. The thin rigid elongated member (16) is free to move within the elongated hollow rigid member (10) through the opening/hole (14). The thin rigid elongated member (16) includes a miniature hook (16a) at its distal end. The curved shape (12) of the elongated hollow rigid member (10) includes a slit (18) adapted on inner periphery thereof. Further, the curved shape (12) may include at least one second hole (20) configured on outer periphery underside the slit (18).

Working of the preferred embodiment of device (100) is illustrated with reference to figures 1 and 4-9. FIG 1 shows a typical endoscopic surgery. The FIG 1 shows a tissue surface (200). For example, the tissue surface may be abdominal fascia, where FIG. 1 indicates the side sectional view of an inflated abdomen of a patient during a laparoscopic surgery. The operative area includes several organs. FIG 1 also shows some surgical instruments such as a scissor or grasper (110) and a light source (120) along with device (100) of the present invention. In a typical reduced port laparoscopic surgery various instruments are inserted through the one or more ports (110a), (120a) and the like.

The device (100) in a laparoscopic procedure can be used by first weaving a thin elongated flexible member (22) as shown in FIG. 4. The thin elongated fastener is selected from any one of sutures, nylon string, thread and the like. The thin elongated fastener, for example a suture (22) is adapted to have a loop (22a) at its one end, and other end (22b) is a free end. In a preferred embodiment, the suture (22) is weaved on the device (100), such that the loop (22a) is maintained at the distal end of the curved shape (12) and the said free end (22b) then passes along the curved shape (12), goes out and comes back through the second hole (20) and then passes through the rest of the curved shape (12) finally coming out the first hole (14). This free end (22b) is then twisted on the elongated straight portion of the device (100) in the form of a knot (22C) as shown in FIG 4. The suture (22) finally passes out of the trocar and into the surgeon's hand.

The suture (22) is partially or fully and temporarily restrained within the ' slit by covering means (24) such as but not limited to tape, plastic sleeves, perforated plastic sleeves, dissolvable plastic sleeves or a combination of these as shown in FIG 6. In an embodiment, the suture (22) is made of dissolvable material such as but not limited to PLLA (Poly L Lactic acid) and the like. In a preferred embodiment, the suture (22) has such a cross section such that it can easily come out of the slit (18) at an instance of surgeon's choosing during the surgery. In another embodiment, the suture (22) has a variable cross section along its length such that one cross section is slightly thicker than the other, so that it restrains the untimely motion of the suture (22) out of the slit (18).

A surgeon gains access into the inflated abdominal fascia, by piercing the surgical device (100) through the abdomen and using the shearing tip at the distal end to make the incision. Once the surgeon locates the concerned tissue (25) such as a blood vessel in the abdomen for haemostasis or ligation, or a cystic duct during a cholecystectomy, the surgeon can lift the tissue for better grip and visibility using the curved shape (12) as shown in Fig. 4. Once the tissue is gripped within the curved shape (12), the surgeon advances the hook (16a) of a thin rigid elongated member (16) through the hole (14) to grab the loop (22a) of the suture (22) at the distal end of the curved shape (12) as shown in Fig. 5. The surgeon then retracts the hook (16a) back in the hollow elongated tube (10) and holds it in that position as shown in Fig. 6 and 7. Now the tissue is locked between the suture (22) and the curved shape (12) of the surgical device. The surgeon then manoeuvres the device (100) in order to move the loosely tied knot out of the distal end of the curved shape (12) as shown in Fig. 8. Once the knot is fully passed out of the curved portion, a loop is formed around the tissue like a lasso, as shown in Fig. 9. The surgeon can then pull the free end (22b) of the suture (22) for tightening the knot. As the loop and the knot start constricting, the tissue undergoes ligation or haemostasis in case of a blood vessel.

Advantages of the invention

1. The device (100) is easy to use during laparoscopic surgery. ,

2. The haemostasis of the tissue supplying blood to the organ under operation can be done quickly and as the suture is bio-absorbable in some embodiments, there is no need to remove the knot after operation.

3. The device (100) can be inserted from an incision much smaller than usual devices. Typically, it may be possible to use this device with an incision less than 2 mm in diameter, or in some cases less than 1 mm in diameter. Such "needle-scopic" incisions provide a variety of clinical benefits. The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.