JPH0259736B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an aqueous humor ejector for draining aqueous humor from a human eyeball suffering from glaucoma.

[Prior art and problems]

Glaucoma is a condition in which the internal pressure in the eye chamber (usually referred to as intraocular pressure) increases due to various causes. When suffering from glaucoma, the eyeball becomes hard and
In severe cases, vision deteriorates, the field of vision narrows, and even blindness occurs.

The conventional treatment for this is aqueous humor drainage surgery, which includes methods that involve implanting an aqueous humor drainer and methods that do not. When performing aqueous humor drainage surgery without implanting an aqueous humor drainer, the eyeball is incised until it reaches the anterior chamber (to the back of the conjunctival tissue), and the aqueous humor pressing on the cornea from inside is drained. do. Over time, this drained aqueous humor oozes into small blood vessels and lymph vessels and is absorbed.
This type of aqueous humor drainage surgery can be successful if performed properly. Unfortunately, however, approximately 20% of cases will recur long after surgery, and approximately 30% will develop cataracts. The main reason for this is that the surgically created opening does not drain the aqueous humor as expected, or it drains too much. As a result, the osmotic pressure in the eye decreases, resulting in cataracts, or tissue adheres to the scar at the incision site, reducing the success rate of surgery.

To date, efforts have been made to solve the above problems using implantable devices, but none have been completely successful. The implanted device uses a drainage tube that is held integrally with an opening made in the affected eye to drain the aqueous humor. A typical example is one that connects the aqueous humor drainage tube to the aqueous humor drainage device itself, which is sutured to the sclera. The purpose of this ejector body is to increase the discharge area of the aqueous humor so that the aqueous humor can be discharged at a sufficiently high speed. After such an aqueous humor drainer is surgically implanted, a scar is formed around the main body of the drainer, and the aqueous humor leaks into blood vessels and lymphatic vessels through this scar. This scar immobilizes the implanted aqueous humor drainer. However, if this scar becomes too thick, it prevents the aqueous humor from seeping into the surrounding blood vessels and lymphatic vessels. This is like a layer of paper, and in order to ooze out at the same rate (compared to a thin scar or a single layer of paper), the aqueous humor drain, like the multiple layers of paper, must be removed. The surface area must also be increased. Therefore, if a thick scar forms around this type of aqueous humor drainer, it will fail unless the surface area of the drainer body is appropriately increased. In a healthy eye, the pressure of the aqueous humor in the anterior chamber is 14 to 16 mm of mercury. If the pressure of this aqueous humor exceeds 20 mm of mercury, the aqueous humor drainer is considered to have failed. According to the results of reliable medical tests, the inside of the cornea is filled with mercury more than 6 months after implantation of an aqueous humor drainer.
If it is less than 20 mm, the aqueous humor drainage device is definitely successful.

A typical prior implantation device (UK Patent Application No. 2,101,891) uses an evacuation tube made of thin silicone rubber, which is connected to one or more rigid disk-shaped members. It is something. This disc-shaped member is the ejector body and is sutured to the sclera of the eyeball. This type of aqueous humor drainer often fails. This is because the surface area of the ejector body is not suitable for sufficient evacuation of aqueous humor.

[Purpose of the invention]

An object of the present invention is to provide an aqueous humor drainer that eliminates the drawbacks of the conventional devices and can reliably maintain the pressure inside the eyeball at less than 20 mm of mercury for at least 6 months after implantation for almost all patients. With the goal.

[Summary and effects of the invention]

The purpose is that the aqueous humor drainer has a drain tube for draining the aqueous humor from the anterior chamber of the eyeball, and a drain body for dispersing the drained aqueous humor over a relatively wide area. The ejector pipe is firmly fixed to the ejector main body and opens directly onto the surface of the ejector main body, and the ejector main body is composed of a band-shaped part, and the width of the band-shaped part is 5 mm or more. The length of the band is sufficient to cover at least a portion of the sclera along the great circle of the eyeball and to be sutured to the sclera, and the aqueous humor drainer has a pressure regulating valve. , this pressure regulating valve is achieved by opening at a predetermined pressure.

By using a strip-shaped ejector body of such width and length, the width is sufficient to maintain the internal pressure of the anterior chamber at less than 20 mm of mercury for more than 6 months after implantation in almost all patients. The seepage area can be secured. Furthermore, by fixing the evacuation tube to the strip of the ejector body, it is possible to prevent scar tissue from forming around the opening (which would otherwise form in the aqueous humor of the eye). (There is a risk that the flow to the band-shaped portion may be dammed.)
The function of the pressure regulating valve is to limit the pressure at which the aqueous humor first flows out of the anterior chamber, so that the aqueous humor within the eyeball can circulate properly over the vitreous body.

The advantage of the pressure regulating valve is that it can be attached to the end of a drain pipe fixed to the strip of the ejector body to allow the aqueous humor to flow directly into the strip. Preferably, this pressure regulating valve has a structure in which one or more slits are provided in the wall of the discharge pipe.

In a preferred embodiment, the drainage tube is arc-shaped and the diameter of the arc is such that the unsupported end of the drainage tube can be positioned closer to the iris than the cornea in the anterior chamber of the eye. selected. By doing so, the unfixed end of the drainage tube does not come into contact with the cornea in the anterior chamber at all, and therefore the cornea can be kept sufficiently transparent. If the diameter of the arc-shaped portion of the discharge pipe is approximately 30 mm,
It can be adapted to almost all eyeballs.

The evacuation tube and ejector body are preferably made of a physiologically inert material, such as medical grade silicone rubber or a hydrogel (such as hydroxyethyl methacrylate).

It is preferable that the width of the band-shaped portion of the ejector body is 9 to 12 mm, and the pressure at which the pressure regulating valve is opened is 4 to 20 mm, in order to suit almost all eyeballs. It is convenient that the discharge pipe is joined to the discharger body by welding or adhesive.

In a preferred embodiment, the evacuation tube extends outside the ejector body and is closed at the end of its extension. In this case, said aqueous humor drainer further has an additional ejector body and an additional evacuation tube, one end of which is connected to the closed extension of said first described evacuation tube. After the end is opened and connected thereto, the other end of the additional ejector tube is fixed to the additional ejector body and opens directly into the surface of the additional ejector body. An additional pressure regulating valve is preferably provided in the additional discharge pipe. The additional ejector body prevents the aqueous humor from exuding if the scar becomes too thick after the initial implantation of the aqueous humor ejector;
Therefore, it can be implanted (preferably subcutaneously) when the intraocular pressure is abnormally elevated. This implantation can be done by performing a simple surgery in areas other than the eye. If necessary, an additional ejector main body may be connected to the additional ejector main body to provide physiological continuity, thereby securing the area necessary for draining the aqueous humor.

〔Example〕

The aqueous humor drainers having two types of structures are based on the present invention, and embodiments thereof will be described below with reference to the drawings.

FIG. 1 shows an aqueous humor drainer 1. This aqueous humor drainer has a drain tube 2 and a drain body 3. The discharge pipe 2 is made of medical silicone rubber and has a length of 24 mm.
mm, thickness is 0.175mm, and inner diameter is 0.3mm. The ejector main body 3 is made of medical silicone rubber, has a band shape, and has a width of 9 mm and a thickness of 0.75 mm. The evacuation pipe 2 is fixed to the ejector body 3 by fusion bonding or gluing (the fixed part is designated by reference numeral 4). In reality, the raised portion of the fixed portion 4 is cut off flat. The discharge pipe 2 is provided with one or more slits 5 (FIGS. 3a to 3d), and the portion provided with the slits 5 is fixed to the discharger body 3. This slit in the discharge pipe 2 acts as a pressure regulating valve. The front discharge pipe 2 is a partial circle with a diameter of 30 mm.

FIG. 2 shows the aqueous humor drainer 1 attached to the eyeball 10. This eyeball 10 is a diseased eyeball,
Its diameter is usually 25mm. The curvature of the drain tube 2 is matched to the diameter of this eyeball. This will be discussed later. Similarly, the circumference of the ejector body 3 is set to a length suitable for the length of the sclera 11 of the eyeball 10 in a great circle. When using the aqueous humor drainer, after attaching the drainer body 3 to a proper position, both ends of the drainer body 3 are sutured and trimmed if necessary (if it is too long). FIG. 2 shows the vitreous body 12 and cornea 1 of the eyeball 10.
3, the iris 14, and the anterior chamber 15 are shown. This figure also shows the free end of the drainage tube, which passes through the incision in the ciliary body 16 into the anterior chamber.
Enter into 5. In addition, in this FIG. 2, the unfixed end of the curved portion of the discharge tube 2
4 and the cornea 13. Furthermore, since the discharge pipe 2 is curved as described above, its unfixed end automatically occupies the proper position. This is extremely important. The reason for this is that the unfixed end of the drain tube must never touch the corneal epithelium (the cell surface on the back surface of the cornea 13). If you touch it, the cornea will become opaque. This is clearly not desirable. By automatically locating the unfixed end of the drainage tube in the space behind the cornea, ie, in the anterior chamber, as described above, the drainage tube can be removed without special surgical precautions. Malfunctions can be prevented. Furthermore, if the drain tube is curved as described above, the epidermis of the cornea of the human eye, which varies in size and shape from person to person, can be automatically kept sufficiently transparent. Naturally, if the patient's eyeball is smaller or larger than a "standard" eyeball, the bend of said drain tube 2 will be made smaller or larger than 30 mm in diameter accordingly.

The pressure regulating valve is shown in Figure 3a. This pressure regulating valve consists of a single slit 5 in the "top" of the discharge pipe 2, this slit 5 having a length of 3 mm. 3rd b
A pressure regulating valve having two or three slits 5 is shown in FIG. 3 and FIG. 3c. Furthermore, the evacuation tube 2 shown in FIG. 3d is fixed (melted and bonded) in the ejector body 3, the slit 5 of which the "top" of the evacuation tube being provided in the recess of the ejector body. Depending on the mechanical properties of the wall of the discharge pipe in this recess, it is necessary to use one or more slits 5 in order to obtain the required pressure regulation value.

The pressure regulating valve is used to control the rate of aqueous humor drainage. If a pressure regulating valve is inserted into the eyeball, which has high internal pressure, the aqueous humor will drain extremely quickly. If the internal pressure of the eyeball increases, choroidal detachment may occur, which may damage the vitreous body. However, by using the pressure regulating valve, such problems can be prevented and there will be no adverse effect on the affected eyeball. do not have.

As explained above, the aqueous humor drainer completely eliminates the drawbacks of conventional aqueous humor drainers.
In particular, it has the following characteristics. That is, (a) the surface area of the ejector main body 3 is sufficiently large, so that the aqueous humor oozes out appropriately. If the surface area of the ejector main body 3 is large, the aqueous humor will flow appropriately due to physiological pressure, and even if the tissue at the attachment part thickens, the internal pressure of the eye chamber will become too high (the mercury column will exceed 20 mm). Never. Relatedly, scars (scars) of the aqueous humor ejector device
Another advantage is that the thickness is moderate (not excessively thick). This is because the rate at which aqueous humor is secreted is equal to the rate at which it flows out, and the scar tissue is absorbed into the blood vessels and lymph nodes by the normal internal pressure of the eyeball.

(b) Since the drain tube 2 is firmly fixed to the drain main body 3, no scar is formed around the unfixed end of the drain tube 2, and the flow of aqueous humor is not obstructed. It is.

(c) The pressure regulating valve not only prevents the aqueous humor from excessively flowing out from the anterior chamber 15 when first installed, but also is fixed to the ejector main body 3 which has the next largest surface area, so that the pressure regulating valve prevents the scar from leaving the anterior chamber 15. The point is that the tissue becomes clogged and the aqueous humor flows continuously towards the ejector body, from which it oozes through the scar tissue and into the blood vessels and lymph vessels.

[Other Examples]

It goes without saying that various modifications can be made to the aqueous humor drainer 1 described above. For example, the width of the ejector body 3 is usually 9 to 12 mm for a "standard" eyeball, but can be 5 to 15 mm for a "standard" eyeball. In this case, it is preferable that the ejector body, which has a width of 5 to 9 mm, be used exclusively for elderly people. The reason is that older people have less resilience to wounds than younger people. If the width of the ejector body is made wider than 15 mm, the patient will see double objects when they move their eyes. Therefore, if the ejector bodies are installed in the same way and symmetrically,
Its width must not exceed 15mm. However, if the ejector body is mounted somewhat asymmetrically, the width of the ejector body can be increased to approximately 18 mm relative to a "standard" eye. Further, there is no need to limit the material of the discharge pipe 2 and the discharge device main body 3 to silicone rubber (silicone rubber is still a preferable material). Said alternative materials include, for example, hydroxymethyl mercaptan.

Further, instead of the curved discharge pipe, an inclined discharge pipe may be used. For example, the tube is tilted inward and then placed through the iris of the eye and into the anterior chamber at the angle shown. Although such an angled drainage tube can be used in some cases, it is easier to perform surgery if a curved drainage tube is inserted in a curved direction.

Additionally, changes may be made to the pressure regulating valve. For example, if the thickness of the pipe wall of the discharge pipe is (0.75
mm), the discharge pipe is connected to the ejector body, a hole is drilled in the connection, both sides of the drilled hole are covered with a thin membrane, and one or more slits are provided in one of the membranes. It can also be used as a pressure regulating valve. This thin membrane can also be made of the same material (preferably silicone rubber) as the ejector tube and ejector body.

In addition, the method for fixing or gluing the discharge pipe to the ejector body is modified such that a friction-matching sleeve made of silicone rubber is used to prevent the discharge pipe from separating from the ejector body (so that it is fixed by a scar). ) You can also change the method to firmly fix it.

The aqueous humor drainer 1 described above should work well in most cases (in other words, when the internal pressure of the eye chamber is maintained at less than 20 mm of mercury for 6 months or more), but in some cases If this happens, problems will obviously occur. In order to be able to deal with such problems without making further incisions in the eyeball, the fourth
An aqueous humor drainer 1' having the structure shown in FIGS. 8 to 8 can be used. This improved aqueous humor drainer 1'
Like the aqueous humor drainer 1, it has a drain tube 2 and a drain body 3, and is embedded in the eyeball 10 as shown in the figure. This improved aqueous humor drainer 1' is different from the aqueous humor drainer 1 described above in that the drain pipe 2 has an extension portion 2a.
(FIG. 4), and this extended portion 2a extends beyond the portion of the discharge pipe that is fixed to the discharger body. A stopper 2b is usually provided at the end of this extension 2a.

If the internal pressure of the chamber of the eyeball 10 exceeds 20 mm of mercury (this is because the scar bulges around the ejector body 3 and almost stops the aqueous humor from seeping out), Further ejector bodies 7 (FIG. 7) can be added to increase the area for the aqueous humor to ooze out. This additional ejector main body 7 has a small piece made of medical silicone rubber attached to the extension part 2a of the evacuation tube (after removing the plug 2b), a silicone rubber tube 8 and a connector 9 (sixth (Fig.). This joint is inserted and held by sutures and medical grade silicone adhesive outside the range of eye movement, preferably subcutaneously on the patient's head. The pipe 8 is provided with a pressure regulating valve 5' which, like the pressure regulating valve of the discharge pipe 2, forms one or more slits in the pipe 8. The value of the pressure that opens this additional pressure regulating valve 5' may be the same as the pressure regulating valve 5, or it may be higher or lower, depending on the condition of the patient. Decide accordingly. As is clear from the above explanation, the addition of the part added to increase the exudation area, that is, the ejector main body 7, is a very simple surgery, and there is no need to perform surgery on the eyeball itself.

Although it is not preferable, if the internal pressure of the eye chamber becomes too high again, it is sufficient to add the ejector main body 7' to the additional ejector main body 7, and this addition can be done by suturing and medical silicone adhesive. All that is required is a bonding agent. In this case as well, the surgery is extremely simple and does not require surgery on the eyeball itself.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an aqueous humor drainer according to the present invention, FIG. 2 is a schematic diagram of the aqueous humor drainer of FIG. FIG. 4 is a schematic diagram of a second embodiment of the present invention implanted in the eye, and FIG. 5 is an additional drain to the embodiment of FIG. 4. Schematic diagram of the state in which the part to which the vessel body is added is provided, No. 6
The figure is an enlarged sectional view of the attachment portion of the additional ejector body shown in FIG. 5, and FIG. 7 is a plan view of the additional ejector body attached to the attachment portion of the additional ejector body shown in FIG. FIG. 8 is a plan view of the ejector main body of FIG. 7 with an additional ejector main body attached. 1,1'...Aqueous humor drainer, 2...Drain tube, 2
a... extension part, 3... ejector main body, 4... fixed part, 5, 5'... slit, 7... additional ejector main body, 8... additional ejector pipe, 9... connector, 10
...Eyeball, 11...Sclera (sclera), 12...Vitreous body, 13...Cornea, 14...Iris, 15...Anterior chamber, 16...Ciliary body.

Claims (1)

[Scope of Claims] 1. The aqueous humor drainer includes a drain tube for draining aqueous humor from the anterior chamber of the eyeball, and a drain main body for dispersing the drained aqueous humor over a relatively wide area. the ejector pipe is firmly fixed to the ejector main body and opens directly onto the surface of the ejector main body, the ejector main body is composed of a band-shaped part, and the width of the band-shaped part is 5 mm or more. and the length of the band is sufficient to cover and suture at least a portion of the sclera along the great circle of the eyeball, and the aqueous humor drainer is connected to a pressure regulating valve. An aqueous humor drainer, characterized in that the pressure regulating valve opens at a predetermined pressure. 2. The pressure regulating valve is located at an end of the drain pipe that is fixed to the band-shaped portion of the ejector body, and the pressure regulating valve has an opening, and when the opening opens, the aqueous humor is discharged. 2. The aqueous humor ejector according to claim 1, wherein the aqueous humor flows directly onto the surface of the band-shaped portion of the ejector body. 3. The aqueous humor drainer according to claim 2, wherein the pressure regulating valve comprises one or more slits formed in the wall of the drain tube. 4. The drainage tube is curved in an arcuate shape, and the diameter of the arcuate portion is such that, in use, the unfixed end of the drainage tube is held in a position closer to the iris than the cornea in the anterior chamber. The aqueous humor drainer according to any one of claims 1 to 3, characterized in that the length is such that the length of the aqueous humor drainer is such that the length of the eye can be obtained. 5. The aqueous humor drainer according to claim 4, wherein the diameter of the arc portion is about 30 mm. 6. The aqueous humor drainer according to any one of claims 1 to 5, wherein the drain tube and the band-shaped portion of the drainer body are made of medical silicone rubber. 7. The aqueous humor drainer according to any one of claims 1 to 5, wherein the drain tube and the band-shaped portion of the drainer body are made of hydroxyethyl methacrylate or other hydrogel. 8. The aqueous humor drainer according to any one of claims 1 to 7, wherein the width of the band-shaped portion is within a range of 9 to 12 mm. 9. Claim 1, wherein the pressure regulating valve opens at a pressure of 4 to 20 mm of mercury.
The aqueous humor drainer according to any one of items 8 to 8. 10. The aqueous humor drainer according to any one of claims 1 to 9, wherein the drain pipe is joined to the band-shaped portion by welding or adhesive. 11 the discharge tube extends beyond the strip;
The aqueous humor drainer according to any one of claims 1 to 10, characterized in that the end of the elongated portion is closed. 12 an additional ejector body and an additional ejector pipe, one end of which is opened after the closed end of the extended portion of the ejector pipe previously described is opened; Claim 11, wherein the other end of the additional ejector pipe is fixed to the additional ejector body and opens directly into the surface of the additional ejector body. Aqueous humor drainer described in. 13. Claim 12, characterized in that an additional pressure regulating valve is provided in the additional discharge pipe.
Aqueous humor drainer as described in Section.