WO2015144995A1

WO2015144995A1 - Method and device for washing out pseudoexfoliation (pex) material using a balanced salt solution (bss) irrigation cannula in combination with cataract surgery for lowering intraocular pressure

Info

Publication number: WO2015144995A1
Application number: PCT/FR2014/000066
Authority: WO
Inventors: Van Tao TRAN
Original assignee: Tran Van Tao
Priority date: 2014-03-28
Filing date: 2014-03-28
Publication date: 2015-10-01

Abstract

The invention relates to a simple physiological technique intended for washing out pseudoexfoliation (PEX) material using BSS (balanced salt solution) on the trabecular meshwork and/or in the iridocorneal angle. Said technique is carried out after the time when an intraocular implant is placed in the capsular bag during cataract surgery. Said technique lowers the intraocular pressure. The washing is also applied with good results in cases of ocular hypertension without PEX material. The invention also relates to a cannula (1) having, on the front end (3) thereof, at least one opening (4) for creating a stream of balanced salt solution, or BSS, pointing in front of the cannula so as to wash out, clean away, and detach the masses of PEX material on the trabecular meshwork and/or in the iridocorneal angle. The invention also relates to the use of said method and device in the field of eye surgery.

Description

"Washing method and device

Seudoexfoliation (PEX) by a balanced saline solution (BSS) irrigation cannula combined with a cataract operation to lower the tension

ocular "

The present invention relates to a method and a device for washing pseudoexfoliation (PEX) on the trabeculum and in the iridocorneal angle by a balanced saline irrigation cannula (BSS) combined with cataract surgery to improve vision and lower eye strain.

Pseudoexfoliative glaucoma with ocular hypertension is manifested by the presence of pseudoexfoliation (PEX) deposits or associated with trabecular pigment cells or in the iridocorneal angle, including secreted PEX deposits of the aqueous humor.

Over time, on the subject aged over 50, the deposits pass to the vitreous to form white spots called cholesterolose, are fixed on the Zinn zonules, the anterior surface of the lens in the pupillary area, the edge of the iris, on the anterior surface of the iris, on the endothelium of the cornea and finally on the trabeculum and in the iridocorneal angle.

These deposits accumulate abundantly in the lower part of the anterior chamber, also called the lower part of the anterior chamber. The more deposits accumulate on the trabeculum, the more aqueous humor stagnates in the anterior chamber, and the greater the ocular tension. This corresponds to the mechanism of increase of ocular tension due to the presence of PEX. The anterior segment photography, the gonioscopy as well as the UBM (microscopic ultrasound) help to visualize and confirm the existence of these deposits.

In accordance with the present invention, the pseudoexfoliation washing (PEX) method and device in the presence of ocular hypertension is combined with cataract surgery to promote the exit of aqueous humor through the trabecular meshwork. to lower the ocular tension.

A cataract is an opacification of the lens in one eye and can lead to blindness. It has long been known to extract a cataractous lens from the eye of an affected person.

A cataract is caused by the accumulation of proteins on the lens of the lens, hence its opacification, which prevents the transmission of light and consequently a normal vision for the affected person.

This opacification of the lens may occur with the aging of the patient but it is possible that this opacification is caused by congenital factors or systemic pathological conditions or is due to trauma to the eye.

Currently the procedure of treatment of a cataract is a surgical procedure with the removal of the lens of the eye of an affected person and its replacement by an intraocular implant.

This removal of the lens can be done in a known manner by intracapsular or extracapsular extraction. The intracapsular extraction consists of the removal of the crystalline nucleus and the capsule enclosing the crystalline lens, thus of the entire crystalline, from the patient's eye while the extracapsular extraction consists in the ablation of the crystalline nucleus without ablation of the capsule enveloping the nucleus which remains in the eye of the patient.

The extracapsular extraction has evolved to a reduction of the portion of the lens capsule retained in the eye until only the back portion of said capsule is left in the eye. The extracapsular extraction also has the advantage of promoting the insertion of an intraocular implant behind the iris and just in front of the rear part of the capsule remaining in the eye, which is a very favorable insertion position for the said intraocular implant.

There is also another mode of lens extraction affected by cataract which is phacoemulsification. Phacoemulsification consists of a small incision in the eye with removal of the diseased lens from the affected person's eye. Phacoemusification is preferred according to the present invention for cataract surgery.

In phacoemulsification, removal of the lens is accomplished by ultrasonic energy and aspiration of said lens out of the eye by the surgical apparatus. As for other modes, an intraocular implant is inserted into the eye instead of the cataractous lens.

Such an intraocular implant is also called artificial crystalline lens or intraocular lens and has a central part called optical which performs the function of crystalline lens and a peripheral portion that carries the fixation of the implant in the eye.

These different procedures and a Laser beam procedure have been satisfactory. However, postoperative complications are common. These postoperative complications may involve damage to the cornea, which damage is frequently caused by high eye pressure.

The applicant of the present patent application has found, surprisingly, that in case of elevated ocular hypertension in pseudo-exfoliative glaucoma, washing of PEX associated with cataract surgery makes improving vision and lowering ocular tension.

OA-07/047242 discloses aqueous solutions containing hyaluronidase as an ocular tension reducing agent and an antioxidant as well as their method of application for preventing postoperative ocular tension increases, for example, following a cataract removal operation.

In this document, it is described that phacoemulsification and other methods of extracapsular lens removal require the use of an aqueous saline solution that irrigates the inner chamber of the eye during the ablation operation. This irrigation maintains the shape of the eye and, in particular for phacoemulsification, cools the ultrasonic tip of the ablation apparatus.

According to this document, for all the modes of a cataract lens removal, irrigation also allows the removal of particles of the cataract lens. During the surgical procedure, the eye is constantly supplied with irrigation solution while the irrigation solution present in the eye is aspirated, which maintains a balanced tension in the eye. However, this document does not deal with the problem of eliminating the proteinaceous material that can serve as a basis for the formation of a pseudoexfoliation syndrome.

EP-A-1,759,675 discloses an end cannula for a surgical manual irrigation tool, especially for the removal of a crystalline lens from a cataract affected eye.

The end cannula, described in this document, has an irrigation nozzle which is disposed laterally on the cannula. Fan dispersion occurs around the cannula when pressurized fluid is ejected from the cannula.

Such an irrigation nozzle is not suitable for washing clusters of precursor material pseudoexfoliation syndrome. In addition, this document does not mention the pseudoexfoliation but on the contrary indicates that the tool is intended for the removal of capsule pieces of the lens after ablation.

The problem underlying the present invention is to avoid post-operative complications after an operation to remove the lens of the eye, by removing clumps of material present in the eye that can form one or more clusters creating a pseudoexfoliation syndrome.

To this end, the subject of the invention is a method for ablating the lens of a cataract-affected eye and replacing it with an intraocular implant, which method comprises a step of irrigating the eye, characterized in that that during a post-treatment step for the ablation and the replacement of said lens, the clusters of precursor material of a pseudoexfoliation syndrome present on a portion of the eye to be treated are removed by washing, this washing being performed by a jet substantially perpendicular to the portion of the eye to be treated.

Advantageously, the washing is carried out at least on the trabeculum or in the iridocorneal angle of the eye.

Advantageously, the ablation is done by intracapsular or extracapsular extraction, phacoemulsification or laser radiation.

Advantageously, the washing time is two minutes in the lower part of 180 ° of the iridocorneal angle and one minute in the upper part of the remaining angle.

Thus, the method of the present invention relates to the washing of PEX deposits and pigments on the trabecular meshwork and in the iridocorneal angle in order to clean or release deposits on the trabeculum allowing the flow of aqueous humor to pass easily. the trabeculum and the aqueous veins. The washing or the detachment of the deposits on the trabeculum makes the physiology of the aqueous humor flow able to extract it out of the anterior chamber, which allows a reduction of the ocular tension because there are no more obstacles formed. by PEX deposits on the trabecular meshwork.

The method according to the present invention is simple and makes the physiology of the aqueous humor able to pass the trabecular mesh to lower the ocular tension.

The postoperative result is also simple and physiological. It may be possible to reserve the place of the sclera at the top of the eye for other conventional glaucoma procedures later in the case of one or more recurrences. The washing cannula is used with the balanced saline jet spray or BSS pointing straight at the trabecular meshwork. Due to a greater accumulation in the lower part of the anterior chamber, the washing is larger or longer than half the lower part of the anterior chamber with respect to other parts of the chamber.

According to the results obtained, the washing carried out on the trabecular meshwork and the iridocorneal angle in the lower half (180 °) at the bottom lasts two minutes and for half of the remaining part at the top lasts one minute. In principle, washing is more important at the lower part of the anterior chamber upwards. The tip of the cannula should approach as close as possible to the trabeculum.

The movement of the washing cannula is slow and in the space of the angle to avoid contact with the endothelium of the cornea. The stream of saline solution or BSS, directed by the cannula is directly pointed to the trabecular meshwork.

The invention also relates to a cannula forming the end portion of a washing device for the implementation of such a method, characterized in that it has at its front end facing the portion of the eye washing at least one outlet opening of a stream of washing liquid substantially perpendicular to the portion of the eye to be treated.

Advantageously, the cannula has at its front end two openings separated by a nose, the jet leaving one opening being fused with the jet exiting the other opening to give a unidirectional jet substantially perpendicular to the portion of the eye to treat.

Advantageously, each opening has a length of 1 to 4 times greater than its width. Advantageously, the two openings are of equal size, the width of the nose being 1 to 5 times less than the length of an opening.

Advantageously, the cannula has a substantially cylindrical body with a diameter of about 1 mm, this body being terminated by the front end having a triangular section in the longitudinal median plane of the cannula.

The invention also relates to a washing device, which comprises a reserve of washing liquid, characterized in that it has such a cannula.

Advantageously, the washing liquid is based on a balanced salt solution or BSS.

Advantageously, the washing liquid comprises an agent making it possible to avoid an increase in the ocular tension in the operated eye.

The invention will now be described in more detail but in a nonlimiting manner with reference to the appended figures, in which:

FIG. 1 is a schematic representation of a perspective top view of the front end of the cannula according to the present invention,

FIG. 2 is a schematic representation of a perspective side view of the front end of the cannula according to the present invention,

- Figure 3 is a schematic representation of a front view in perspective of the front end of the cannula according to the present invention.

In a known manner, the PEX or pseudoexfoliation material is secreted by the aqueous humor of the ciliary body. With time, on subjects older than 60 years, the pseudo-exfoliation spreads and accumulates progressively on Zinn's zonule, the anterior surface of the lens, on the edge of the iris around the pupil, on the anterior surface of the iris, on the endothelium of cornea, on a trabeculum and in an iridocorneal angle.

Over time, the more PEX build-up on the trabeculum causes greater stagnation of the aqueous humor in the anterior chamber. This creates an ocular hypertension. It is the mechanism of ocular hypertension and pathology called pseudoexfoliative glaucoma involving high ocular tension. Most often, the ocular tension is very high and it is very difficult to treat.

According to the studies conducted by the applicant, it is found that most cases are associated with hypercholesterolemia. This suggests that hypercholesterolemia is the likely predisposing factor for PEX or ocular hypertension without PEX.

Advantageously, according to the present invention, the PEX washing process is carried out at least on the trabeculum or the iridocorneal angle. The washing method according to the invention is combined with a cataract operation to eliminate the deposition of PEX on the trabeculum so as not to retain the flow of the aqueous humor exiting in the passage of the trabecular meshwork.

This helps to lower the eye pressure. This technique can be used to lower the ocular tension in the case of PEX glaucoma, PEX-free ocular hypertension or blood washing, foreign bodies on the trabeculum or in the angle.

Advantageously, the washing time is two minutes in the half of the lower part of 180 ° C. the iridocorneal angle and one minute in the remaining upper part of the angle.

In the process of cataract surgery, two input ports at the periphery of the cornea were created in width of one millimeter. According to the present invention, the washing is carried out by a cannula with the jet of water pointing to the trabecular meshwork in the eye. The irrigation cannula of saline solution or BSS arises in the incision and is directed towards the opposite irido-corneal angle and then changed to point to another part of the angle.

The present invention relates to a method for ablating the lens of an eye affected by cataract and replacing it with an intraocular implant, which method comprises a step of irrigating the eye, characterized in that during a step post-treatment to the ablation and the replacement of said lens, the clusters of precursor material pseudoexfoliation syndrome present on a portion of the eye to be treated are removed by washing, washing being carried out by a jet substantially perpendicular to the portion of the eye to be treated.

According to the present invention, the washing is done by a washing device having a cannula at its outlet end of BSS wash liquid or balanced saline solution. A cannula according to the present invention is shown in Figures 1 and 3.

The cannula 1 forms the end portion of a washing device for carrying out the method according to the invention. The cannula 1 is formed of a substantially cylindrical body 2 and a front end 3 facing the trabecular meshwork and / or the iridocorneal angle to be washed. This front end 3 of the cannula 1 carries at least one outlet opening 4 of a stream of saline solution or BSS directly to the trabecular meshwork.

In Figures 1 to 3, the cannula 1 has at its front end 3 two openings 4 separated by a portion forming the nose 5 of the cannula 1 being the most forward part of said cannula 1.

The nose 5 advantageously has a rounded shape. The nose 5 has a reduced width so that the two jets issuing respectively from an opening 4 can merge in front of the nose 5 of the cannula 1.

The jet emerging from an opening 4 of the front end 3 of the cannula 1 is directed towards the front of the cannula 1 while being parallel to the longitudinal axis of the cannula 1. In the case of two openings 4 for one cannula 1, the jet emerging from an opening 4 is fused with the jet leaving the other opening 4 in order to give a unidirectional jet, substantially perpendicular to the trabeculum and / or the iridocorneal angle of the eye to be treated .

The cylindrical body 2 of the cannula 1 advantageously has a diameter of 1 mm and the front end 3 of the cannula 1 has a triangular section in the longitudinal median plane of the cannula 1 to facilitate entry into the incision port of the horny and without risk of damaging it.

The angle at the apex of the triangular section at the base of the nose 5 of the front end of the cannula 1 may advantageously be from 10 to 60 °.

The median longitudinal axis of each opening 4 extends on a respective side of said triangular section of the front end 3 of the cannula 1. Advantageously, each opening 4 has a length of 1 to 4 times greater than its width.

Advantageously, the two openings 4 are of equal size and the width of the nose 5 is 1 to 5 times less than the length of an opening 4.

The washing liquid is preferably based on a balanced salt solution or physiological BSS which is standard in the process of cataract surgery.

The direct effect of the method and the device according to the present invention is to wash, clean and eliminate the deposition of PEX on the trabecular meshwork and / or in the iridocorneal angle in order to lower the ocular tension.

The cannula used according to the present invention is a cannula s ¹ similar to that of irrigation in the process of operation of cataract. The difference is that the balanced saline jet stream or BSS is a direct stream that points to the part of the eye to be washed, which can be composed of the joining of two jets on each side of the cannula, these jets being fused into one another. a single jet pointing in front of the cannula.

The power of the jet depends on the height of the saline bottle or BSS. The base height is 90cm compared to the cataract phacoemulsification device and varies in the range between 90cm and 110cm.

A method according to the present invention with such a cannula is very simple to implement and physiological because there is no other incision, suture or implant to add to that necessary for the operation of cataract.

The main advantage is a lack of major and frequent complications in the operation classic filtering or non-filtering glaucoma such as athalamia, hyphema, choroidal detachment, ocular hypotension or persistent ocular hypertension.

Since 2007, for nine patients, eleven eyes have undergone a respective PEX wash, each wash being combined with a cataract operation. Postoperative follow-up after four years still shows normalization of ocular tension. There has not yet been a reappearance of visible PEX on the edge of the iris or on the trabeculum and / or in the iridocorneal angle, which has been monitored by gonioscopy and UBM.

For these eleven washes, there was no complication with the exception of mild and transient ocular hypertension immediately the day after the operation in one eye. The ocular tension went down and was renormalized later. This is explained by the fact that the PEX deposits are detached from the trabeculum and / or the iridocorneal angle and then reoccupy the trabecular meshwork temporarily. This problem can be solved by taking medication (eg, Diamox®) to give the patient six hours after the procedure.

Since 2009, the method according to the present invention has been applied to cases of ocular hypertension without PEX. The result is also very encouraging. This is probably explained by the same mechanism of micro-PEX deposits, but invisible by slit lamp or UBM examinations. The micro-PEX washing on the trabeculum and / or the iridocorneal angle leads to a reduction of the ocular tension.

Claims

A method of ablating the lens of an eye affected by cataract and replacing it with an intraocular implant, which method comprises a step of irrigating the eye, characterized in that during a step of treatment to the ablation and the replacement of said lens, the clumps of precursor material pseudoexfoliation syndrome present on a portion of the eye to be treated are removed by washing, washing being carried out by. a jet substantially perpendicular to the portion of the eye to be treated.

2. Ablation method according to the preceding claim, wherein the washing is carried out at least in the iridocorneal angle of the eye or the trabecular meshwork.

3. Ablation method according to the preceding claim, wherein the washing is carried out at least in the iridocorneal angle and the washing time is two minutes in the lower part of 180 ° of the iridocorneal angle and one minute in the remaining upper part of the corner.

The method of ablation according to any one of the preceding claims, wherein the ablation is by intracapsular extraction, extracapsular extraction, phacoemulsification or laser radiation.

5. Cannula (1) forming the end portion of a washing device for carrying out the method according to any one of the preceding claims, characterized in that it has at its front end (3) facing at the portion of the eye to be washed at least one outlet opening (4) of a jet of washing liquid substantially perpendicular to the portion of the eye to be treated.

6. Cannula (1) according to the preceding claim, which has at its front end (3) two openings (4) separated by a nose (5), the jet leaving an opening (4) being fused with the jet coming out of the other opening (4) to give a unidirectional jet substantially perpendicular to the portion of the eye to be treated.

7. Cannula (1) according to the preceding claim, wherein each opening (4) has a length of 1 to 4 times greater than its width.

8. Cannula (1) according to one of the two preceding claims, wherein the two openings (4) are of equal size, the width of the nose (5) being 1 to 5 times less than the length of an opening ( 4).

9. Cannula (1) according to any one of the four preceding claims, which has a substantially cylindrical body (2) with a diameter of about 1 mm, this body (2) being terminated by the front end (3) having a section triangular in the longitudinal median plane of the cannula (1).

10. Washing device, which comprises a reserve of washing liquid, characterized in that it has a cannula (1) according to any one of the five preceding claims.

11. Washing device according to the preceding claim, wherein the washing liquid is based on a balanced salt solution or BSS.

12. Washing device according to the preceding claim, wherein the washing liquid comprises an agent for preventing an increase in ocular tension in the operated eye.