MEATIC PLUG WITH SIMPLIFIED INSTALLATION.

Abstract

Meatal plug, comprising a stem and a bulb disposed at one end of the stem, the bulb projecting laterally beyond the stem, a hole being formed in the plug, the hole opening at the end of the stem opposite the bulb, and the hole extending at least into the bulb, is characterized in that the ratio of the height dimension of the stem, measured along its longitudinal axis, to the length dimension along this same axis of the bulb, is greater than 1, preferably greater than 2.5; and the ratio of the width dimension, that is to say measured in the direction perpendicular to the axis of the stem, of the bulb to its length is greater than 1, preferably greater than 2.5.

Description

1 Simplified-fitting meatal plug. The present invention relates to A meatal plug intended to block a meatal opening of a lacrimal duct in the human eye. The present invention also relates to a device for inserting such a plug. Finally, the present invention also relates to a method for blocking a meatal opening of a lacrimal duct in a human eye. The punctal plugs known today consist of a body with a stem and a bulb located at one end of the stem, protruding laterally like a mushroom. This bulb is inserted into the lacrimal duct sufficiently deep to reach a shoulder located beyond the duct and thus, by abutting against this shoulder of the lacrimal duct, locks in place, preventing the plug from escaping the duct. This type of device works very well. However, it is difficult to insert, particularly into the lacrimal duct. To do so, the duct must be dilated to allow the passage of the plug's bulb. The present invention aims to overcome these drawbacks by providing a punctal plug that can be inserted more simply and quickly into the lacrimal duct, and in particular, one that does not require prior dilation of the lacrimal duct, or at least requires only minimal dilation.According to the invention, a meatal plug, comprising a stem and a bulb disposed at one end of the stem, the bulb projecting laterally beyond the stem, a hole being formed in the plug, the hole opening at the end of the stem opposite the bulb, and the hole extending at least into the bulb, is characterized in that the ratio of the height dimension of the stem, measured along its longitudinal axis, to the height dimension along this same axis of the bulb, is greater than 1, preferably greater than 2.5; and the ratio of the width dimension, that is to say measured in the direction perpendicular to the axis of the stem, of the bulb to its height, measured along the longitudinal axis of the stem, is greater than 1, preferably greater than 2.5.The inventors realized for the first time that by creating a bulb with a flattened, hollow shape, it was easy to pre-stretch the plug along the axis of the stem using a pusher / stretcher inserted through the hole (10). This temporarily reduced the bulb's thickness, allowing its insertion into the tear duct. Simultaneously, the flattened or compact shape of the bulb (15) ensured that the plug would withstand the stretching operation and regain a shape after removal of the insertion device, enabling it to fit securely in the tear duct, particularly at the shoulder extending beyond the duct.20 According to a preferred embodiment of the invention, the hole terminates in the bulb by flaring out to form a hollow chamber having a width greater than the width of the hole at the stem, preferably a width 25 greater than the width of the stem itself. Preferably, a collar projecting laterally beyond the stem is provided at the end of the stem opposite the bulb. 30 Preferably, the collar has a cylindrical shape of revolution about the axis of the stem. Preferably, the bulb has a shape such that its outer surface is rounded, without having angular corners. 35 The deformation of the plug before its insertion into the channel is thus facilitated. Preferably, the stem has a circular cylindrical shape. 2906712 3 The present invention also relates to a device for inserting a plug according to the invention.A device according to the invention comprising a pusher body, in the form of a rod, intended to be inserted into the hole formed in a meatal plug to stretch it, is characterized in that it is provided with retention means intended to retain the plug at a retention point while the rod is inserted therein, to stretch the plug relative to the retention point.10 According to a preferred embodiment of the invention, the retaining means consist of two clamps arranged at the end of the device by which the rod is pushed, the at least two clamps being able to take a first position in which they 15 jointly form a stop in the form of a plate pierced with a hole through which the rod of a stopper can pass but through which a collar cannot pass when the latter is provided at one end of the rod of the stopper, and a second position separated from each other by 20, in which the stopper, and in particular the collar, is released from the two clamps.Thus, to insert the plug, the collar is brought against the plate formed by the ends of the two clamps. Then, the rod is pushed through the hole in the plug to stretch it and place it in the tear duct. The rod is then withdrawn, and the clamps are spread apart to release the plug, which is now in position. An embodiment of the invention is now described by way of example, with reference to the drawing.Figure 1 shows a longitudinal cross-sectional view of a plug according to the invention; Figure 2 shows a perspective view of a plug according to the invention; Figure 3 is an exploded perspective view of a placement and stretching device according to the invention; and Figure 4 is a larger-scale perspective view of an end portion of the device of Figure 3, while Figure 5 is a cross-sectional view of an end portion of the device of Figure 4; and Figure 6 is a cross-sectional view of a portion of a human eye comprising a plug arranged according to the invention. Figure 1 shows a longitudinal cross-sectional view of a meatal plug according to the invention. This cap, made of stretchable and elastic material, in particular silicone, in particular coated with a thin layer of Poly Vinyl Pyrrolidone, is cylindrical in shape with respect to the longitudinal axis 1.The meatal plug 15 comprises a cylindrical stem 2 extended at one end by a bulb 3 projecting laterally from the stem 2. At the other end of the stem 2 is a collar 4, which is formed here substantially perpendicular to the longitudinal axis 1. According to another embodiment, a collar inclined with respect to the longitudinal axis 1 at an angle other than 90° could also be provided. A hole 5 is formed in the plug. It opens into an opening 6 on the side of the collar 4. This hole 5 consists of a first section 7 which extends substantially along the entire length of the stem 2, then flares out into a second intermediate section 8, and terminates in a chamber 9 inside the bulb 3.The largest width dimension (in the direction perpendicular to axis 1) of chamber 9 is greater than the width dimension of section 7 and also, preferably, greater than the width dimension of stem 2. According to the invention, a dividing line or plane between the bulb and the stem is defined as the straight line 10 that separates stem 2 and bulb 3. This straight line 10 is located at the point where stem 2 terminates, that is, where its outer surface begins to protrude beyond the substantially vertical wall 11. Below the dividing line 10 is the stem, and on the other side is the bulb. According to a preferred embodiment of the invention, the hole 5 has a diameter of 0.33 mm in section 7, while stem 2 has a diameter of 0.55 mm. The largest dimension in width of chamber 9 is approximately equal to 0.85 mm.The largest width dimension of bulb 3 is approximately 1.1 mm. The dimension along the longitudinal axis of bulb 3, that is, the dimension between line 10 and the apex of bulb 3, is 0.38 mm. The length dimension of stem 2 from opening 6 to plane 10 is 1 mm. The length dimension (in the direction of axis 1) of the collar is approximately 0.1 mm. The largest width dimension of the collar is approximately 1 mm. The ratio of the length dimension (height) of stem 2 to the ratio of the length dimension (height) of bulb 3 is thus 1 / 0.38, or 2.6. The ratio of the width dimension of bulb 3 to its height dimension is 1.1 / 0.38, or 2.9. The wall delimiting the cavity formed in the bulb has a thickness of approximately 0.12 mm.The outer surface 25 of the bulb 3 is rounded, notably by being formed in longitudinal cross-section (Figure 1) by a succession of circular arcs. It does not have corners forming an angle. The thickness of the wall delimiting the section 7 of the stem 2 is 0.18 mm. Figure 3 shows a device for inserting a plug according to the invention into position. This device consists of a main body 100 in which a conduit 101 is defined, through which a stem 102 can be pushed. The stem 102 35 supports at its end a pushing needle 103 designed to be inserted into the hole 5 of the plug, to reach the cavity 9, push the bottom of the cavity 9, and stretch the wall of the bulb of the plug 9 until it is deformed and less flattened to allow its insertion into the lacrimal canal 104.At the end of the device 100, on the side where the rod 102 will be pushed, there is a sleeve 104 that can be removed from the body 100 by 5. This removable sleeve 104, which is hollow and cylindrical in shape, has at its end, intended to be on the side where the end 103 of the rod 102 will be pushed, two clamps 105 which, at their free end, 10 come into contact with each other to form a stop plate 106 through which a hole 107 is formed, the diameter of which is such that it can grip the rod 2 without the collar 4 being able to pass through. These two clamps 105 are connected to the sleeve 104 15 by two thin sections 108 which thus allow the two clamps 105 to be easily separated from each other to release the plug. To insert the plug into the lacrimal canal 120, the clamps 105 are positioned so that the hole 107 20 encircles the rod 2 while the collar 4 butts against the plate 106.Next, the rod 102 is pushed through the hollow sleeve 104 and the hole 107 to reach the hole 5, in order to push and stretch the bulb 3. Once the bulb 3 is stretched 25 and thus less flattened, it can be pushed into the canal 120 until the bulb 3 protrudes from the shoulder 121 formed at the end of the lacrimal canal. Once in this position, the rod is withdrawn and the clamps are separated to release the meatal plug 30. Figure 6 shows a plug according to an embodiment in which the collar is inclined at an angle other than 90° to the rod, specifically from 70° to 80°, which allows for a better conformity 35 with the opening of the lacrimal canal on the eye side. 2906712 7 The material used for the stopper is in particular PDS silicone or poly dimethyl siloxane, in particular with a hardness of 30 to 80 Shore, for example 50 Shore.The material and thicknesses of the plug, particularly the thickness(es) at the bulb, are chosen so that the bulb has sufficient elasticity to substantially return to its original shape after being stretched along the longitudinal axis of the stem, and at the same time is strong enough to withstand this stretching (i.e., a stretch such that, in the stretched state, the plug has a width substantially equal to that of the stem) without being damaged. For example, for 50 Shore PDS silicone, the thickness of the bulb wall at its widest point is preferably between 0.14 mm and 0.18 mm, in particular 0.16 mm, while the thickness at the cross-section with the longitudinal axis is preferably between 0.10 mm and 0.20 mm, in particular 0.12 mm. The ratio of the width of the bulb to its height is between 1 and 5, preferably between 2 and 4.

Claims

DEMANDS 1. Meatal plug, comprising a stem (2) and a bulb (3) disposed at one end of the stem, the bulb projecting laterally beyond the stem, a hole (5, 6, 7, 9) opening at the end, the hole extending to the end formed in the plug, the hole of the stem opposite the bulb, and less into the bulb, characterized in height from the longitudinal, to the axis of the bulb, is greater than 1, preferably greater than 2.5; and the ratio of the dimension in width, that is to say measured in the direction perpendicular to the axis of the stem, of the bulb to its height is greater than 1, preferably greater than 2.

5.

2. Stopper according to claim 1, characterized in that the hole ends in the bulb by flaring out, to form a hollow chamber (9) having a width dimension greater than the width dimension of the hole at the level of the stem.

3. Stopper according to one of claims 1 or 2, characterized in that it is provided at the end of the stem opposite the bulb, a collar (4) projecting beyond the stem laterally.

4. Plug according to any one of claims 2 to 3, characterized in that a width dimension of the hole is greater than the width dimension of the stem itself.

5. Plug according to any one of claims 1 to 4, characterized in that the bulb has a shape such that its outer surface is rounded, without having angular corners, thus facilitating the deformation of the plug before its insertion into the channel. The ratio of the stem dimension, measured along its axis, to the height along the same axis is 2906712 9 6. A stopper according to any one of claims 1 to 5, characterized in that the stopper is made of silicone, in particular PDS. 5 7. A stopper according to any one of claims 1 to 6, characterized in that the thickness of the bulb wall at its greatest width is preferably between 0.14 mm and 0.18 mm, in particular 0.16 mm, while the thickness e2 at the cross-section with the longitudinal axis is preferably between 0.10 mm and 0.20 mm, in particular 0.12 mm. 15 8. A stopper according to any one of claims 1 to 7, characterized in that the ratio of the width of the bulb to its height is between 1 and 5, preferably between 2 and 4. 20 9. Device for installing a meatal plug according to any one of claims 1 to 8, comprising a pusher body, in the form of a rod, (102, 103) intended to be inserted into the hole (5) formed in a meatal plug to stretch it, characterized in that it is provided with retention means (105, 106, 107, 108) intended to retain the plug at a retention point while the rod is inserted therein, to stretch the plug relative to the retention point.

10. Device according to claim 9, 30 characterized in that the retaining means (105, 106, 107, 108) consist of two clamps (105) arranged at the end of the device by which the rod is pushed, the at least two clamps being able to take a first position in which they jointly form a stop in the form of a plate (106) pierced with a hole (107) through which the rod of a cap can pass but through which a collar cannot pass when the latter is provided at one end of the rod of the cap, and a second position apart from each other, in which the cap, and in particular the collar, is released from the two clamps.