RU2385695C1 - Vitrectomy knife - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: vitrectomy knife comprises a handle and a working part that represents a plate consisting of a front acute-angled triangular element and a back trapezoid element attached thereto. The front acute-angled triangular element is pointed; its end surface is at an acute angle to the longitudinal symmetry axis of the working element. The plate is bent along the longitudinal symmetry axis of the working piece congruentially to the eyeball surfaces and transversely to the longitudinal axis with radius 0.20 to 0.35 mm. The acute angle of the front triangular element lays in the range 15 to 45 degrees, and the back trapezoid element is pointed.

EFFECT: application of given invention allows reducing injures of tissues in vitrectomy.

6 dwg

Description

The invention relates to the field of ophthalmic surgery.

Known knife for vitrectomy, containing a handle and a pointed working part. The working part is made in the form of a flat pointed triangular plate (see H.P. Tahchidi. Selected sections of eye microsurgery. Vitreous body. M., 2002, p.23).

However, this device has a significant drawback: a significant trauma to the tissues of the eye, especially with vitrectomy, since the incision is made across the scleral layers, without taking into account their natural direction. In addition, this device does not provide self-sealing of the section.

The closest analogue is the knife used for eye surgery (US 2007179515 A1, 02/02/2007), containing a working part made of a front acute-angled triangular element and a rear trapezoidal element connected to it, both elements are interconnected by sides opposite their acute angles, the front an acute-angled triangular element is made in the form of a pointed plate, the end surface of the front acute-angled element is located at an acute angle to the longitudinal axis of symmetry of the working part.

The disadvantage of this knife is that only the front acute-angled triangular element is pointed, the entire knife is made flat, and therefore the self-sealing incision cannot be made with this knife due to the formation of a vaulted tunnel inside the tissues, eye tissue is injured when cut. The knife is not suitable for vitrectomy operations, as it does not take into account the anatomical features of the eyeball.

The technical result of the invention is the reduction of tissue trauma during vitrectomy.

The specified technical result is achieved by the fact that the vitrectomy knife containing the handle and the working part, made in the form of a plate consisting of a front acute-angled triangular element and a rear trapezoidal element connected to it, while the front acute-angled triangular element is pointed, its end surface is located under an acute angle to the longitudinal axis of symmetry of the working part, according to the invention, the plate is curved along the longitudinal axis of symmetry of the working part congruent to the surface of the h apple apple and across the longitudinal axis, with a radius of 0.20 to 0.35 mm, while the acute angle of the front triangular element lies in the range of 15 to 45 degrees, and the rear trapezoidal element is made pointed.

The combination of distinguishing features of the invention proposed by the authors is necessary and sufficient for the unique achievement of the claimed technical result.

The invention is illustrated by drawings in figures 1-6.

Figure 1 is a top view.

Figure 2 is a bottom view.

Figure 3 is a side view.

Figure 4 - section aa.

5 is a sectional view.

6 is a sectional Profile in longitudinal section.

The vitrectomy knife contains a handle (not shown in the drawings) and a pointed working part. The working part consists of a front acute-angled element 1 and a rear trapezoidal element 2 connected to it (Figure 1). Elements 1, 2 are interconnected by sides opposite to their acute angles. Elements 1, 2 are made in the form of a pointed plate 3 (Figure 2). The plate 3 is curved along the longitudinal (Figure 1) symmetry 4 congruent to the surface of the eyeball with a radius of 12.0 to 15.0 mm. The plate 3 is also curved across the longitudinal axis of symmetry 4 of the working part with a radius of 5 from 0.2 to 0.35 mm (Figure 4). Figure 4 shows that the edges of the plate 3 are pointed from the inside. The bending radius cannot be less than 0.2 mm, since the size of the incision will be insufficient for vitrectomy, and can not be more than 0.35 mm, as this increases the surgical trauma. The acute angle ά of the front triangular element 1 lies in the intervals from 15 to 45 degrees. The angle cannot be less than 15 degrees, since the size of the incision will be insufficient, and more than 45 degrees, since the size of the incision should not increase operational invasiveness (Figure 1).

In this case, the end surface 5 of the front acute-angled triangular element 1 (Fig. 1) is located at an acute angle to the longitudinal axis of symmetry 4 of the working part.

The curvature of the longitudinal axis of symmetry of the working part, (Figure 3), congruent to the surface of the eyeball, allows to reduce the deformation of the layers of the sclera. The execution of the end surface at an acute angle to the longitudinal axis of symmetry of the working part allows you to reduce deformation when the knife enters the eye tissue.

The implementation of the working part curved across the longitudinal axis of symmetry with a radius of curvature from 0.2 to 0.35 mm allows you to form a self-sealing section through the formation of vaulted tunnel inside the tissues.

The sharpness of the lower edge from the inside of the working part also contributes to the formation of a self-sealing section due to the fact that the cut layers are inside the tunnel formed inside the tissues.

Work with the proposed device is as follows (Fig.5, 6).

The tissue section of the eye is made in one stitching movement with an inclination of 15-30 degrees to the longitudinal axis. When passing the working part in the sclera, an inclined vaulted tunnel is formed (Figs. 5, 6), the transverse and longitudinal curvature of which is also congruent with the transverse and longitudinal radius of curvature of the working part of the tool. During the reverse movement, the cutting edges of the widest part of the instrument additionally dissect the choroid, which is soft internal tissues of the eye, on a rigid support - the sclera, which were not sufficiently dissected during direct movement due to their softness and lack of rigid support.

Using the proposed invention allows to reduce trauma to the tissues of the eye and to form a self-sealing incision in the scleral layers of the eye.

Claims (1)

Vitrectomy knife containing a handle and a working part made in the form of a plate consisting of a front acute-angled triangular element and a rear trapezoidal element connected to it, while the front acute-angled triangular element is pointed, its end surface is at an acute angle to the longitudinal axis of symmetry of the working parts, characterized in that the plate is curved along the longitudinal axis of symmetry of the working part congruent to the surface of the eyeball and across the longitudinal axis with a radius of 0.2 0 to 0.35 mm, while the acute angle of the front triangular element lies in the range from 15 to 45 °, and the rear trapezoidal element is made pointed.

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