CN1239877A

CN1239877A - Method and apparatus for adjusting corneal curvature using corneal ring with removable biocompatible material

Info

Publication number: CN1239877A
Application number: CN97180432A
Authority: CN
Inventors: 约瑟夫·Y·李
Original assignee: MICOROAUPTICS CO Ltd
Current assignee: MICOROAUPTICS CO Ltd; MicroOptix LLC
Priority date: 1996-12-09
Filing date: 1997-12-09
Publication date: 1999-12-29
Also published as: EP0964660A1; AU730045B2; KR20000069361A; BR9714386A; AU5596698A; WO1998025547A1; CA2274800A1; JP2001508327A

Abstract

A method and apparatus for adjusting corneal curvature of the eye comprising an adjustable split ring formed of an elastic hollow shell which is implantable into the cornea in encircling relation to the central optic zone of the cornea. The ring is filled by a predetermined amount with a select quantity of biocompatible material, either a fluid or strands of biocompatible suture material or polymethylmathacrylate, of predetermined size and length. The biocompatible filler material is strategically located within the elastic shell to alter its dimensions in thickness or diameter and thereby adjust the corneal curvature to correct for refractive error. Further adjustment of the ring may be made post-operatively after implantation by select removal of the biocompatible filler material.

Description

Regulate the method and the device of corneal curvature with corneal ring with removable biological adaptation material

The application requires the No.08/761 of December in 1996 submission on the 9th, 362, submitted No.08/829 on April 1st, 1997, the No.08/856 that submitted on May 15th, 846 and 1997, the priority of 650 U.S. Patent application has comprised the subject matter of each application of these applications here fully.

The present invention relates to a kind of method and apparatus that is used for regulating corneal curvature, particularly relate to a kind of implantable device that is suitable for embedding in the eye's cornea, this device can be revised the size of its volume that replaces when embedding, and when operation subsequently,, perhaps expand described device and come the correction of refractive error with solid material by regulating or from this implanting device, removing solid material.

Ametropia is a kind of refractive status of not expecting of eyes, and ametropia has three kinds of main disaggregated classifications: myopia, hypermetropia and astigmatism.Up to now, myopia is prevailing a type of ametropia, and with regard to myopia, parallel rays 20 enters into eyes as shown in Figure 1, arrives the focal point F 1 that is positioned at retina 24 the place aheads, as shown in Figure 2.For hypermetropia, light 20 arrives the focal point F 2 that is positioned at retina 24 rears, as shown in Figure 3.When convergence of rays be not one but on several focus the time, this is called astigmatism, each focus may all be positioned at retina the place ahead or all be positioned at the retina rear or part is positioned at retina the place ahead, part is positioned at the retina rear in this case.

Ametropia is proofreaied and correct by glasses or recessive glasse usually.Yet these refraction confusions also can be proofreaied and correct by surgical operation.The refraction eye surgery is defined as acting on the surgical operation of the dioptric quality that changes eyes on the eyes.Present more common refraction therapy comprises the laser ablation (as U.S. Pat 4,941,093 is described such) of radial angle membranectomy (as U.S. Pat 4,815,463 and US4,688,570 described like that) and corneal stroma.Other various surgical methods that are used for the correction of refractive confusion were attempted, and comprised the thermokeratoplasty that is used for treating hypermetropia, be used for proofreading and correct the outer ceratoplasty of serious hypermetropia and can make the central cornea steepen or smooth keratomileusis.Keratomileusis is that the Barraquer of Colombia (Colombia) proposed in 1961, comprises that mainly grinding cornea becomes a suitable shape to come the correction of refractive error, replaces the cornea of shaping again.Some more common cornea refraction therapies are discussed below, and wherein neither one has shown the whole characteristics with ideal cornea refraction therapy.The shortcoming of cornea refractive surgery comprises: limited is predictable, lacks reversibility, the cornea unstability, and the vision area fibre modification, operation aftersensation discomfort, and dazzle the eyes, dizzy, and asterism (starbursts).

In radial angle membranectomy (RK), make the peripheral radial slot of multiple tracks in 90%-95% the degree of depth of cornea, thereby so that central cornea partly flattens smooth correct myopia.By to implementing operating patient's multiple retrospective analysis widely, the problem of result's Unpredictability is solved.These researchs have disclosed following these and it seems it is certain factor of controlling surgical result, such as the size of vision area, and initial corneal astigmatism registration, corneal diameter, corneal rigidity, otch quantity, notch depth, intraocular pressure, corneal thickness, and astigmatic degree.Age and sex also are the factor of being considered in most nomogram, and this figure is designed to the effect of predicting that a particular surgeries is desired.Wherein, many experts in this field think that it almost is impossible fully accurately proofreading and correct the patient in a surgical operation, they think that RK should be the surgical operation in two stages, in the surgical operation of beginning, obtain the correction of " be similar to ", strengthen by one that step is regulated subsequently or this result of titration and the approaching result desired one eyes.Have realized that, because individual's variability, can cause individual undercorrection or excessive correction and be different from situation about predicting by nomogram, in a surgical operation, attempt complete correction of refractive error and may cause the operating excessive correction of the percentage ratio of can not ignore, and cause more difficult gauged hypermetropia.Unfortunately, the surgical operation of this second stage even be lower than predictable in the beginning process.Nobody has designed a formula of considering the important change that takes place after the RK of beginning on cornea, particularly when over and done with several weeks or several months.Many eyes of 50-60% of only researching and proposing after the RK obtain 20/20 or better vision.Before operation, get used to 20/20 or better the patient of correct vision is generally dissatisfied is lower than 20/25 or 20/30 uncorrected postoperative vision.

In addition, the transformation of hypermetropia is a RK main factor afterwards gradually.Refraction stability is strict for all refraction therapies, but all corneas refraction therapy demonstrates significant unstability.So far, not about why cornea because RK and unsettledly clearly explain.Recently a report about the long-term results of RK is pointed out emphatically: " nature " hypermetropia refraction progress of " normally " eyes is the functions at age.Possible patient begins by exaggerated correction, and the adaptive capacity of this exaggerated correction by the patient covers up.Along with the forfeiture of time and adaptive capacity, hypermetropia may come out gradually, and hypermetropia becomes visible symptom.When operation, because crystalline adaptive capacity, the patient can be corrected as slight hypermetropia and still have 20/20 vision.Have a residual gauged scope, the patient can have 20/20 not correct vision in this scope.This scope depends on the individual and changes, but may be across 2 to 3 diopters.Even in this scope, the percentage ratio that obtains 20/20 vision only is 50-60%.This reflects the pitiful precision of this technology.Along with the forfeiture of hypermetropia or adaptive capacity, this scope can reduce, and notices that described this situation is important, and this situation normally began in the time of 45 years old.This causes obtaining the percentage ratio of 20/20 vision from 50-60% above-mentioned decline.Clearly, after the RK of beginning had carried out, RK was not suitable as a kind of easy, safe, foreseeable therapy and regulates refraction results.After this incident, the viewpoint that majority is pleased with the cornea shaping has been empirical fully.Therefore need consider a kind of easy method of finely tuning refraction correction in earnest, this method minimally is invaded and is carried out easily.

The laser host resectional therapy such as anaclasis keratectomy (PRK) current trend that is used for the correction of refractive confusion, and has obtained suitable success.Yet these therapies are not still exempted the problem of Unpredictability.Basically, in the treatment of myopia, laser energy acts on the central cornea part, thereby causes more central tissue cut and that cornea is flattened is smooth.Unfortunately, final refraction effect is not only decided by the quantity of excision, and is decided by the recovery reaction of corneal excision.This cornea produces new collagen actively, and in other reaction, epithelium experiences a proliferation response, attempts to repair the infringement on its surface.This causes rollback, or changes towards myopia backward, and this may little by little take place through the period of the hop count moon a to several years.The sedimental a kind of institute of new collagen not desired effects is the substrate cicatrization, and this expression substrate muddiness may reduce patient's sensitivity by contrast.This corneal stroma opacification differently is called fibrosis, cicatrixization or muddiness, this and the rollback that reduces vision and relative sensitivity, refraction effect, and the night vision of difference is relevant.The same with RK, the predictable of PRK is a problem.Most conclusions about through the result after the PRK treatment myopia of publishing show that 80-94% eyes have obtained 20/40 or better correct vision not, and the percentage of patients that obtains 20/20 vision significantly diminishes.These numerals are not consider such fact,, as previously explained, have a residual refractive scope that is, still can see 20/20 this scope patient.Can think that those obtain a part suitable among the people of 20/20 vision and are actually slight hypermetropia after PRK.Along with the time, suitable percentage ratio is easy to develop into " gradual hypermetropia " among those patients, or exposes potential hypermetropia.Like this, cannot be accepted by the definition of ideal refraction therapy although obtain the percentage of patients of 20/20 vision after PRK, it can resemble and enlarge the result initial when adopting RK.Although vision restoration is slow when RK, it is than fast after the PRK.Second kind of normally careful carrying out of laser ablation therapy because it can cause very strong recovery reaction, even has the rollback bigger than beginning process.In addition, as in RK, this laser ablation therapy is not foreseeable fully, and this partly cause wherein is because a unpredictable people's wound restores reaction.

Considered to adopt the refractive surgery of cornea implant can be used for correction of astigmatism for many years.Early stage technology comprises the thin slice removal of nature angle membrane matrix tissue or adds, as in keratomileusis and the corneal lens art.These need adopt micro-keratome to remove the part of cornea, use subsequently or the cornea of (corneal lens art) excision of patient (keratomileusis) or donor comes lath-shaped to cover this cornea.This equipment complexity, the surgical operation difficulty, and more disappointed be that the result is very indefinite.Towards the technical development of the wound that reduces cornea, this minimally stimulates the recovery reaction of wound to the present trend of cornea refractive surgery, and with a kind of more foreseeable form effect.Adopt the interior crystal of heterogeneous plasticity (alloplastic) cornea to proofread and correct the refractive status of eyes, at first proposed by Jose Barraquer in 1949, this technology is perplexed by biocompatibility, problems such as permeability, cornea and crystalline hydration situation to nutritional labeling and oxygen.Adopt these crystalline other problems to comprise: the operation technique of the central optical axis might be followed the interface cicatrix.

Be absorbed in the effect of wound being restored reaction by avoiding central cornea towards the effort of the renewal of correction of refractive error and be reduced to minimum.There has been multiple trial to change the curvature of central cornea by the cornea around the surgical treatment.These technology are discussed owing to them and certain relevant of the present invention.

In the preface of textbook that Jose Barraquer is shown " principle of refractive surgery and put into practice ", " as my result of initial publication, some creators determine to attempt the profile that diverse ways is adjusted cornea.The thing that temporarily comprises of perforation substrate excision and plasticity dish has carried out attempting (1960) by Krawawicz, the use of trepan has carried out attempting (1976) by Pureskin, sotoimpronata has carried out attempting (1964) by Strampelli, mold pressing has carried out attempting (1965) by Martinez and Katsin, and corneal ring has carried out attempting (1966) by Blawatkaia.”

Zhivotosvskii, the patent No.3887846 of the former Soviet Union of D.S. have described, and annular ring a kind of heterogeneous plasticity, flat, regular geometry is no more than the cornea implant of pupil diameter as an internal diameter.The refraction correction mainly radius of curvature on the surface by making ring is finished greater than the radius of curvature of admittance person's anterior corneal surface, so that the middle section planarization of cornea.The operation process that embeds this ring is not described.

A.B.Reynolds (U.S. Patent No. 4,452,235) describes and claimed a kind of cornea refractive technique that comprises method and apparatus, and this technology is used to change the shape of the vision area of cornea, with the correction of refractive error.His method comprises: an end of an annular partition member that separates is embedded in the substrate of cornea, move around cornea with a curved path, the annular that to separate is releasedly regulated parts and is fixed on the end of this partition member, reversibly move this partition member along this path, thereby spur this adjusting parts along this circular path that gets by this partition member, return and remove this partition member, regulate this separately end of annular adjusting parts toward each other, thereby the diameter of regulating this ring changes the diameter and the shape of cornea, and, thereby the desired landforms shape of maintenance cornea firmly fixing by the bonding end that will encircle.

A main advantage of this ring is to have realized MIN wound recovery effect.Significantly corneal wound restores the long-time stability that reaction will reduce any surgery refractive surgery.Yet, there are two scattered-light operating refraction results of tangible problem area influence treatment:

1. first problem relates to the size that is predetermined implant and the ability of shape, and this implant will cause specific refraction results.In RK or PRK, retrospective research is carried out, and has caused the development of nomogram, and the otch of measurable certain depth or certain excision quantity will cause foreseeable correcting value.In this situation that adopts ring, final nomogram will develop into and can be used to a given thickness or the given refraction correction of big circlet prediction.Yet these nomograms always fail to solve fully the variability to the individual in the reaction of given cornea refractive surgery.

2. refraction results also depends on the stability of the refraction correction that obtains after the surgical operation.What reaffirm is, because the MIN wound of supposition restores reaction, the advantage of this ring will be to make the refraction results that is obtained stable.This has reduced the variability of long-term refraction results, but still can not be illustrated in the problem of first problem area, i.e. inherent individual's variability, and the possibility of result is stable, and it can be a stable but insufficient refraction results well.

Even another problem that can not illustrate is to adopt this implant, the surgeon will be intended to the slight undercorrection to myopia, cause the patient of hypermetropia more unfortunate because of common exaggerated correction.In addition, refraction results may be than more stable under the situation of RK or PRK, but it may be a stable but insufficient refraction results.

Simon (U.S. Patent No. 5,090,955) a kind of operating technology has been described, the curvature of cornea is adjusted in permission by a kind of synthesized gel rubber of injection between the cornea perisphere, and do not damage vision area, and operation is removed this gel and is reduced the volume that replaced when carrying out, thereby regulates the final curvature in central cornea zone.

Siepser (U.S. Patent No. 4,976,719) another ring device has been described, by adopting a retaining ring of forming by one surgical cable of making a power ring, or make the curvature of cornea flatten smooth or steepen, wherein thereby this power can be regulated selectively and be allowed the curvature of cornea to change selectively, and this adjustable apparatus comprises one attached to the buckle on this line.

There are several mechanisms, by these devices, the corneal curvature of the operating influence front of cornea periphery.Cornea resembles most soft tissue, is non-linear, viscoelastic, uneven, and can demonstrate than hightension under physiological status.Very complicated on the whole eyes geometry, can systematically simulate this true biomechanics technology is Finite Element Method, little tension force (a kind of measurement of distortion), homogeneity and the linear elasticity behavior of its supposition.Below will do concise and to the point the description to two kinds of simple mechanisms.

A simple example is helpful when understanding first kind of mechanism.Suppose to have between fixing point P1 and P2 a loose rope R, shown in Fig. 4 a, it has formed a curve, in the middle of minimum point is positioned at.With reference to Fig. 4 b, a load w is applied on the rope and locates between a mid point P and a fixing point, will cause the middle body tensioning of rope.Fig. 5 (a) has similar behavior with the cornea C shown in Fig. 5 (b), two fixing point P1 and P2, be similar to the edge of eyes, load W is similar in appearance to substrate implant 30, when being when concerning with the central optic zone of cornea in the implanted cornea of this implant, above-mentioned situation makes corneal collagen fiber (21) above implant locate upwards to depart from, below implant (22) locate downward bias from.In fact, replace departing from of causing, cause other zone of cornea to lose " relaxing ", perhaps locate relative tensioning in (23) as shown in the figure around this of circumcorneal implant by volume in the cornea periphery.

The mechanical expansion of implant diameter is represented by the expansion of the implant (30) shown in the Fig. 6 (b) that compares with Fig. 6 (a), it is smooth that this mechanical expansion of implant diameter also makes central cornea curvature flatten, on the other hand, the contraction of implant 30 makes the corneal curvature steepen, is caused the centre of rope more sagging similar in appearance to two fixed points in the example of Fig. 4 (a) and Fig. 4 (b) towards moving together.This situation can partly take place, because be not completely fixed at the boundary node at edge.In a word, cause small departing from, make the central curvature planarization slightly of cornea, and shrink or the implant of expansion has changed fixing point, thereby changed corneal curvature by the volume of the implant 30 self in the tissue around.The implant of shrinking or expanding may cause lower stable refraction results, separates and dispersion because the inside or outside power of implant corneal substrate may produce the stratiform of further power gradually.As Simon is described,, may obtain stable result more by changing the volume that in peripheral cornea, is replaced.

Second kind of mechanism described with quoting hereinafter by J.Barraquer.Since 1964, " verified, for correct myopia, must reduce thickness from the central authorities of cornea or increase its peripheral thickness, for proofreading and correct hypermetropia, must increase thickness from the central authorities of cornea or reduce its peripheral thickness." comprise that the therapy of minimizing is called " keratomileusis ", comprise that those therapies of increase are called " corneal lens art ".Intrastromal corneal ring is that the periphery has increased volume, and the thickness that increases ring causes on the corneal curvature that makes the front by " increasing (thickness) in the periphery " is smooth a more obvious effect being arranged.

Ideal cornea refraction therapy allows all advantages of glasses or contact lens, promptly, can proofread and correct the error of refraction of relative broad range, accurately or have predictable, allow when the refractive status of eyes changes, need regulate gauged reversibility, MIN complication once more, and technology is simple, low cost, and can aesthetically accept for patient institute.Refractive surgery doctor's target should be to reach 20/20 the not correct vision that long-time stability are arranged greater than 95% patient.Present available refractive surgery therapy neither one can reach the precision and the stability of this degree.

Repeat again, a kind of easy therapy of finely tuning refraction correction and corneal curvature after operation can't obtain, and wherein corneal curvature often is subjected to the change of cornea hydration status, the influence that wound restores reaction and other unknown factor.Described each technology is the such shortcoming of tool all, that is, its degree of accuracy is limited.In technical scheme disclosed in this invention, a kind of method of regulating refraction results easily in the stable back of curvature of cornea has been described, a kind of method of minimally infringement, a kind of method that causes MIN stimulation to the wound reactivation, allow optionally and repeatedly to regulate, and almost completely reversible.It has proposed the discussion of the common problem of Unpredictability, thereby makes that be too dependent on nomogram predicts that refraction results can not explain fully that the individual obsolesces to the application of the therapy of the variable reaction of operation.

According to one embodiment of present invention, a kind of adjustable intramatrical device is provided, it is suitable for implanting cornea inside, it is made of the hollow shell of a flexibility, this shell for example is made of the material of silicone or urethane polymer, and the packing material with an available biological adaptation for example polymethyl methacrylate (PMMA) fill the annular cavity that increases.This packing material can be any biological adaptation material of Any shape and length, but the wire filament of preferably annular and flexible tensile indefinite size.This device is filled with the described biomaterial of scheduled volume, and around in the implanted cornea of the vision area of cornea.Then by removing one or more rings fully so that with a kind of discontinuous form change the volume of this device and cause the corneal curvature steepen and myopia transformation, thereby make corneal curvature adjusted.This birefringence is proofreaied and correct simple relatively adjusting and can be undertaken by common available surgery instrument, and needs the postoperative processing of MIN corneal and implanting device.This device of the present invention is a kind of adjustable implantable device, comprises that one forms an outer barrier film that is used to accept such as the shell of a plurality of ring filling materials, is suitable for the purpose of correction of refractive error and is embedded into the interlayer space of corneal stroma.The volume that this device replaced the easily a plurality of chances after initial implant surgery obtains adjusting, thereby allows to regulate refraction results and do not need to remove this implanting device in later period.

According to another embodiment of the present invention, device in a kind of adjustable substrate is provided, it is inner and formed by the hollow shell of a flexibility to be suitable for implanting cornea, this shell for example is made of the material of silicone or urethane polymer, and the packing material with an available biological adaptation for example saline or gel-filled inner chamber.Preferably, this device has the compartment more than, and each compartment and other compartment all are fluid-tight and independently.Each compartment fills the described biological adaptation fluid of scheduled volume, and this device ring is implanted in the cornea around the vision area of cornea.The volume of the increase that ring is replaced causes the corneal curvature of front center to become more smooth, thus correct myopia.Preferably near-sighted quilt is excessive correction slightly, makes cornea become needed more flat than best vision.After this device was implanted in the cornea, the adjusting of corneal curvature was to be undertaken by the fluid of removing particular compartment selectively, this be with a kind of discontinuous mode reduce implant volume, cause the transformation that corneal curvature is precipitous and produce myopia.

Implant among the different embodiment easily a plurality of chances after initial implant surgery obtains adjusting, thereby allows to regulate refraction results and do not need to remove this implanting device in later period.

Fig. 1 is the sketch map of horizontal profile of people's eyes;

Fig. 2 be presented at myopia state under light be the sketch map that how to focus on amphiblestroid the place ahead;

Fig. 3 is presented at that light is the sketch map that how to focus on amphiblestroid rear under the state of hypermetropia;

Fig. 4 a shows a sketch map that its two ends is suspended on the rope between two fixed points;

Fig. 4 b be the rope among the displayed map 4a put therein and one of fixing point between apply the sketch map of a load;

Fig. 5 a is the sketch map that shows the eyes cornea, wherein cornea be fixed on surrounding edge along on the point of diameter relative position;

Fig. 5 b is an exemplary plot that is similar to Fig. 5 a, but it has shown because of the existence of supporting implant in the substrate in the cornea generation curvature effect on cornea;

Fig. 6 a and Fig. 6 b one are used to show the cross sectional representation of the cornea of the effect that expansion produced after adjustable implant of the present invention is in it implants cornea;

Fig. 7 a is the plane graph of flexible apparatus of the present invention, and wherein this device is cut off by a radial slot;

Fig. 7 b is the diameter cross figure along the amplification of Fig. 7 a Vertical Centre Line 7b-7b;

Fig. 8 a is the cross-sectional view of device of the present invention;

Fig. 8 b is the radius cross section figure of the amplification of tube of the present invention, and wherein the inside of this device is filled by many rings;

Fig. 8 c is the cross-sectional view that is similar to Fig. 8 b, but wherein the ring of some shown in Fig. 8 b is removed from this device;

Fig. 9 is the section of diameter figure of the perspective of this device of the present invention, has shown the angle of conical radius cross section;

The radius cross section figure of Figure 10 a-10d improved form of the present invention;

Figure 11 is the plane graph of this device, has shown the placement of the joint that ring in this implant is possible;

Figure 12 a has shown that with Figure 12 b the ring that is connected that is placed in this implant is cut open the cornea of front and back and the cross-sectional view of device;

Figure 13 a and Figure 13 b show that ring is by the cornea before and after therefrom removing and the cross-sectional view of implant;

Figure 14 a is the radius cross section figure of this device of the present invention, has shown the typical shape of this device;

Figure 14 b is the radius cross section figure of the amplification of the device among Figure 14 a, and wherein the inside of this device is filled with several rings;

Figure 14 c is the radius cross section figure that is similar to the amplification of Figure 14 a, but what show is that inside is filled with less but this device of ring that thickness is bigger on diameter of number;

Figure 15 a can be embedded into the orientation of a plurality of ring materials of inside of this device and the floor map of form; Being spaced apart wherein is convenient to explanation and exaggerated;

Figure 15 b and Figure 15 c are that this device of the present invention is respectively along line b-b among Figure 15 a and the cross-sectional view of c-c;

Figure 16 a, Figure 16 b and Figure 16 c have shown and have been suitable for being embedded into the configuration of the ring in this device and the variation of direction;

Figure 17 a has schematically shown the plane graph of this device of the present invention, and one of them part ring has been embedded in this device; Figure 17 b is that this device among Figure 17 a is along the radius cross section figure of hatching line 17b-17b;

Figure 17 c is that device among Figure 17 a is along the radius cross section figure of hatching line 17c-17c;

Figure 18 a is the cross-sectional view with ring of the inner chamber that vertically separates of the present invention;

Figure 18 b is the cross-sectional view with ring of horizontally separated inner chamber of the present invention;

Figure 18 c is the cross-sectional view with ring of strengthening inwall of the present invention;

Figure 19 a is the plan view of ring, and it has shown two inner chambers that do not extend around ring fully;

Figure 19 b is the plan view of ring, and it has shown two inner chambers that extend around ring fully;

Figure 20 a is the cross-sectional view of embodiment with ring of horizontally separated inner chamber;

Figure 20 b be among Figure 20 a wherein above the cross-sectional view of the ring that punctured of inner chamber;

Figure 21 is the radius cross section figure of an embodiment of ring, has shown the typical dimensions of ring;

Figure 22 a is the cross-sectional view of an embodiment of ring, and this ring comprises two expansible inner chambers, and two inner chambers all separate with the shell of ring;

Figure 22 b is the cross-sectional view of ring after an inner chamber is pierced among Figure 22 a, and the thickness that it demonstrates ring reduces;

Figure 22 c be ring among Figure 22 b at the inner chamber that is pierced by the cross-sectional view after from the ring of this implantation, removing, the thickness that demonstrates ring further reduces;

Figure 23 a is the cross-sectional view with embodiment of three rings that fill fluidic microcapsule;

Figure 23 b is the plane graph that hole or perforation is arranged on ring wall and the ring of two openings is arranged in the separation region of ring;

Figure 24 a to 24d is the radius cross section figure of the improved form of ring of the present invention;

What Figure 24 e represented is the cross-sectional view of the bonded ring of fluid inner chamber and existing filamentary material;

Figure 25 a and 25b shown inner chamber before and after being pierced cornea and the cross-sectional view of ring;

Figure 26 a is the plane graph of another embodiment of this ring, has shown the wherein position of isolating compartment;

Figure 26 b is that ring among Figure 26 a is along the cross-sectional view of hatching line 26a-26a;

Figure 26 c is that ring among Figure 26 a is along the cross-sectional view of hatching line 26b-26b;

Figure 26 d be ring among Figure 26 a along the cross-sectional view of hatching line 26b-26b, it has shown with respect to the cross section of the ring of Figure 26 c thicker wall relatively.

Especially with reference to accompanying drawing, in accompanying drawing 7a, shown the device that comprises an adjustable apparatus 30 of the present invention.This device 30 forms one and admits the shell of implant, this implant be can easily remove such as by natural polymer or comprise the synthesizing polymeric material of polyester, nylon, polypropylene, polyimides, fluoropolymer and filamentary material that the material that is adopted is made when making optical fiber.The packing material of this device can be any biological adaptation material, but preferably a kind of flexibility, can be by the filament that constitutes such as above-mentioned elastomeric polymer.In this piece file, alternately adopt term " ring " and " line ".The cross section of ring can be different geometry, comprises circle, ellipse, rectangle, square or triangle.The cross-sectional area of ring can change dimensionally along its length.This device can comprise one or more ring, and each ring all can be removed in the later stage.

This device 30 comprises one by a kind of flexible material, such as the tube-like envelope 30a that silicone, acrylic acid or urethane polymer are made, and is shown as the annular of opening in a minute in Fig. 7 a.This sheathing material has enough hardness, thereby this device will keep its annular common when plane graph after filling fully, this material also has enough pliabilities, in the time of allowing the filling shown in viewgraph of cross-section Fig. 8 b thickness increase and shown in Fig. 8 c when remove flatten when encircling smooth.The shell of this device must have sufficient structural integrity, intensity and pliability, to keep its annular and expansible under normal conditions.Its combined material can be similar to the material that is adopted when making folding or deformable ophthalmic crystal, such as silicone polymer, urethane polymer and acrylate copolymer, or the material that is similar in soft contact lens to be adopted, or such as the material of fluoropolymer resin.Example by material constituted other the medical apparatus that is suitable for use as shell of the present invention comprises artificial blood vessel, Dialysis tubing or film, blood oxidation organ pipe or film, and ultrafiltration membrane.The shell of this device or packing material can be by one or more natural or synthetic polymer constitute.

This device 30 is an ellipse along the cross section of the sagittal plane at the center of passing this implant, as seeing in the sectional view as shown in Fig. 8 a and Fig. 9.Each all can be improved with the surface parameter of the cross section that changes this device by changing parameter at the different embodiment shown in Figure 10 a-10d, thereby provide a large amount of branch embodiment, described parameter is such as the combined material, device ways of connecting, the ring filling type of material that are this device wall, described surface parameter, for example, by ringwise, the cross section of shape such as square, rectangle, triangle, ellipse forms this device.Shown in Fig. 7 b, the main shaft 39 of the cross section of this device 30 is such, that is, the gradient of the cornea arc of the utmost point adapts before it and the cornea, thereby forms the conic section.This angle approximately is 25-35 degree.The two ends 45,46 of this device are divided into square, thereby they can be arranged side by side mutually shown in Fig. 7 a, and can firmly connect by stitching or bonding these class methods when operation.

This device 30 is suitable for being implanted in the peripheral substrate cornea.Its thickness and geometry are such, that is, it has changed central cornea curvature and has not invaded the central optic zone of cornea after implanting, and does not reduce the diffusion to the nutritional labeling of central cornea.Its size is such, that is, it can easily be embedded in peripheral people's the substrate cornea, and it comprises a biological flexible material that adapt to, that particularly adapt with eye tissue.Size shown in Fig. 7 b comprises the thickness 45 of 0.1-1.5mm, the width 56 of 0.4-2.0mm and the whole external diameter 57 of 3.5-12.00mm.The thickness of the shell 30a of this device 30 can be shown in Figure 10 a-10d and is changed.This device can only comprise the ring 38 of one or more different-diameters and composition.Ring 38 can be made of nonvolatil biological adaptation material, and diameter can change from 0.02mm to 1.0mm.Described nonvolatil biological adaptation material is such as being material used in ophthalmologic operation, for example polymethyl methacrylate, nylon, polyester or polypropylene.This ring can be transparent or chromatic.This ring can carry out labelling towards the head and the afterbody of this device, to help the doctor to regulate tensioning degree when the end of connecting ring.As shown in figure 11, this ring at one end can have ready-formed little ring 66,67, by adopting the instrument that a little hook is arranged in the operating side, can and be convenient to ring is removed with this little hook this little ring of seizure.Replace little ring, the more terminal collocation forms that can have other of this ring are such as an end circle or thickening, the also extracting that will help encircling.By providing resistance at opening, the ring around this little ring also helps to prevent is pulled out simultaneously.The two ends of this ring do not need to connect.

Device of the present invention is designed for the surface curvature of implanting the central optic zone that changes cornea in the eye's cornea and does not invade vision area.It is made of a hollow devices, this device has a variable inner volume, thereby that central optic zone is flattened is smooth by disconnecting ring that tensioning couples together, perhaps make the curvature of central optic zone precipitous by ring being removed to suitable number, so that needed refraction correction to be provided, and the excessive correction and the undercorrection that allow to regulate error of refraction.

The variation of suitable embodiment on shape, size, girth, packing material size and packing material composition is to depend on the amount of error of refraction and selected.In the flaky passage of layer by the degree of depth of the diameter of the amount of the volume that this device replaced, synusia shape passage, width of channel, passage, and the parameter of the position change in refraction that all to be influence obtain by this device.This soft shell 30a that comprises annular material also can change by the embodiment of the implant shown in Figure 10 a-10d.This selection comprises:

1. polymethyl methacrylate (PMMA) skeleton that does not have support.

2.PMMA or other hard physiologically acceptable polymer backbone strengthens the interior periphery of this device wall, shown in Figure 10 c.Thicker region 14 shown in Figure 10 c can have the thickness of increase, and it is to be formed by the flexible material that constitutes wall, and perhaps it can be above mentioned hard polymer backbone.In operation, this interior periphery skeleton can suitably be adjusted and fix with suture or glue, adopts auxiliary rough adjustment of keratome.

3.PMMA or other hard polymer backbone is strengthened the outer periphery of the wall of this device shown in Figure 10 b.

4. the support of interior neighboring.

Selected device size should be such, inferior to can cosily proofreading and correct (not needing to remove whole rings) by said method to the individual variational excessive correction of reaction of operation or the scope of undercorrection.The type of maximum thickness, girth and support frame is selected before embedding this implant.The ideal embodiment of given preoperative refractive status and other related data is selected before operation, and this embodiment needs further operation to decide ideal curvature then.This device is embedded in the peripheral cornea of enough degree of depth, further regulates on retina for the shape of regulating cornea more accurately and the light focusing that will enter in the eyes then.If this device is placed on small depth in the corneal stroma (being about 1/3 to 1/2 cornea degree of depth), be expected to have stronger refraction effect.This device is placed on approaching more periphery in the cornea, and refraction effect is low more.Can proofread and correct 20 diopters that reach myopia potentially near the device that central cornea is placed.Keratoscope when operation is carried out or automatic keratometer may be helpful.Yet the operation mean curvature of carrying out in the operation that relates to cornea measures do not show it is that insight is reproducible in advance.

This device is implanted in and adopts an annular to cut interior 1/2 to the 2/3 cornea degree of depth place of annular flake shape passage that instrument forms open, and this passage only needs a corneal incision between the little periphery.Cut out the radial slot of an about 2mm who begins to the 3.5mm position from CC to 2.5 with scalpel.Only cut in incision on the surface of cornea.Introduce a Suarez dilator in the bottom of otch, thereby produce a little laminar passage.Use vacuum centering guiding device and fix eyeball, an external diameter 8-9mm pass otch be incorporated into laminar channel formation instrument rotation in the laminar passage come to produce at 1/2 to 2/3 corneal thickness place one 360 degree around the passage between the cornea periphery.After the channel formation instrument was removed, the tweezers of the scope type of a circle inserted same passage and rotate 360 degree, thereby the tip of these tweezers is exposed from radial slot.One end of this device is inserted in the tweezers, thus closed this device that grips of forceps jaws, and these circular tweezers rotate and put in place gradually up to this device.The instrument that this device also can adopt an end to have the circle of hook is moved the position to.Circular when the instrument of hook is arranged when adopting, it at first is inserted in the laminar passage in the opposite direction in the side that inserts with ring.Hook is connected with preformed little ring of the front end of adjustable cornea device or hole then, and the instrument that hook is arranged of this circle rotates backward and slowly moves, and moves ring to position gradually.The head and the afterbody of this device gather together, and available suture or glue are fixed together.

In a word, plant bulk, shape, width, outer casing thickness and girth, influence the adjustment or the selection of the factor of corneal curvature and refraction results, occur in three specific temporary transient stages:

1. before operation is carried out, the existence of above-mentioned variable and support frame or do not exist is to adopt from selecting as the nomogram that instructs the retrospective research development of each variable selection.

2. carry out in the process in operation, the tensioning degree of this device is optionally adjusted, and adopts the ongoing keratoscope of operation to assist if necessary.The ring that passes completely through implant can be strained and is connected with various tensioning degrees, sincerely remembers following description:

A. the volume of regulating implant may cause than regulating the more foreseeable corneal curvature variation of trial of corneal curvature by applying tensioning or removal tensioning.

B. if desired be distance vision correction, the radial force of needs circle is kept corneal curvature, and or the tensioning end to end of this device connects or one or more ring tensioning connects.

3. postoperative adjusting.The simple postoperative adjusting of carrying out easily can be implemented by this governor motion practically, and this adjusting has avoided following the complication of operation once more of most of cornea refraction therapies.This postoperative adjusting can compensate the deficiency of the selection of preoperative implant, the hydration situation of cornea in the process is carried out in the compensation operation, after changing, the hydration status of cornea after the operation causes different corneal curvatures, the change in refraction that wound recovery reaction that compensation is not expected and compensation cause owing to ignorance factor subsequently around implant.This postoperative adjusting can be finished by a softish cornea device that includes some rings, and this ring can easily be removed, thereby changes the volume of this device and cause corneal curvature to increase.

Cut at any some place of cornea before ring, preferably above the zone at the removed shell of some front shell place, thus can be easily near ring.Line also can be removed from initial incision.When ring by when remove a position that is different from the head or tail of this device, head and tail portion may be closed, what help encircling thereby the removal of line causes forming partial vacuum collapses.The removal of ring from this device itself compared the interface that minimally has been upset substrate-implant with removing this device, thereby the wound recovery that will take place when regulating and the consequence of edema are reduced to minimum.This postoperative adjusting looks like those needed additional means of any method of managing to reach the standard of ideal cornea-refraction therapy.If refraction results is undesirable, can take these steps:

A. shown in Figure 12 a and 12b, if corneal curvature is too precipitous, the patient is a myopia, and if have a ring to connect with tension force 38, thereby can cut the contraction annulus that it discharges some power, it is smooth to make that corneal curvature 49 flattens.Ideally, this ring is being cut open near the initial incision place.This encircle available one sharp-pointed pin, knife or even laser cut.If still not enough, can cut the ring more than.Even all rings all cut, the two ends of this device can not float.Cause under the too smooth situation in loop slit, wherein a ring can be removed from this device and eyes fully, makes the volume of this device reduce relatively, is accompanied by corneal curvature and becomes precipitous.If be difficult to remove at impossible incident medium ring, this ring can cut at 180 degree places, and each is partly removed from initial incision then.Corneal curvature can reduce by another kind of method.Ring in this device or other solid biological adaptation material can be connected with larger-diameter ring, thereby when the ring in this device was removed, this bigger ring was pulled to the position gradually, so increased the volume of this device, make the corneal curvature of front flatten smooth.

B. shown in Figure 13 a and 13b, if after operation (Figure 13 a) the curvature peace of cornea is smooth, have less relatively tensile or do not have tensile ring to cut and to remove, thereby make corneal curvature become precipitous, be shown with the transformation of an above-mentioned myopia as Figure 13 b.Why Here it is encircles one of them does not at least have corneal that annular radial power is provided.If it is undue precipitous that the removal of excessive correction of exist regulating and ring causes, have tensile ring and can cut and stay original position, thereby make cornea flatten smooth or big new ring is pulled to the position.

A kind of typical adjustable device 30 of the present invention is shown in Figure 14 a.The diameter of outermost approximately is 0.9mm, and whole thickness approximately is 0.3mm, and maximum inner width approximately is 0.8mm, and minimum diameter approximately is 0.20mm.The device of this size can be expected about 3 diopters of correct myopia.Be number that calculates the ring that to install comfortably and the dioptric variation of removing each ring, the supposition below doing.The cross-sectional area of this oval-shaped device approximately is 0.11 square millimeter.Filled because this volume can not have the ring of circular cross section fully, that is, between circular rings, have the space, so be it is desirable to 78.5% by the occupied area of ring.About four (diameter 0.175mm) ring 38b or seven (diameter 0.125mm) ring 38a can be filled into this space.All removing fully of ring causes the smooth of 0.2mm or 2.0 dioptric variations.Be that average diopter that the ring of 0.175mm is removed from this exemplary embodiments changes for each diameter be 0.5 diopter.For each diameter is the removal of the ring of 0.125mm, and variation is 0.3 diopter.Suppose an initial myope, the possibility of result exceeds initial refractive 50%, and hypermetropia still can suitably be controlled by the removal of independent ring.Causing the treatment of hypermetropia in most cornea refraction therapy excessively is a significant disadvantage.The wound reactivation took place in the time of several years in the radial angle membranectomy, often had gradual hypermetropia.The patient who becomes the hypermetropia symptom after operation is very painful.Therefore most of surgeon adopt the nomogram of attempting to obtain slight undercorrection.Once relating to the anaclasis keratectomy in the research, finding that the patient is not owing to the hypermetropia of the eyes of they being done operation is dissatisfied to their second eye with the gauged chief reason of PRK (first eye supposing them are proofreaied and correct with PRK).Technology described here is the gauged hypermetropia of excessive correction easily.

In simple an application of this technology, this device can be used to correction of astigmatism.It is the reason of most astigmatic situation that the curvature of anterior surface of cornea changes.Convergence of rays does not form a prime focus on more than one plane.Astigmatism depends on the appearance of anchor ring usually, and replaces the spheric curvature of eyes refractive surface.Be correction of astigmatism, the degree that the specific region of cornea is need be than other regional correction bigger.This implant can be in the perimeter change of this device of thickness upper edge, and wherein the cross section of this device is corresponding to having the more precipitous gradient and needing bigger gauged zone to have the volume of increase on the cornea.In the diagram of Figure 15 a, ring 32 almost 360 degree is full of this device fully.Another part ring 33 is short and be approximately on the clock and watch 4-6 position in the drawings and lack.Ring 34 is ring mirror-image arrangement of 33, and it lacks in the position that is approximately on the clock and watch at 6-8.Ring 35 folds self twice in the zone that increases thickness.Ring 36 is mirror-image arrangement of 35.The end of ring 37 installs attached to this by glue or other device.End at the ring of opposite side 38 is fixed equally.As by comparing with cross sectional dimensions among Figure 15 c, the volume of the cross section of implant is big indicated among Figure 15 b, has more polycyclic zone the volume that reaches 50% increase is arranged, thereby satisfy needed different correction under astigmatic situation.If astigmatism correction is excessive, ring 35 and 36 can be drawn out up to little ring 31 and be moved out of, and cuts off from the place that this device exposes at ring then.The removal of little ring 31 is reduced to 4/3 to the ratio than the zonule from 6/3 to the big zone of this implant.Under the insufficient situation of astigmatism correction, ring 32 can be removed fully, and this ratio is increased to 5/2 from 6/3.Many different variation on this principle is possible, some examples shown in Figure 16 a, 16b and 16c.Ring 38a-38c as shown in Figure 16 a, the 38d-38g among Figure 16 b and the 38h-38k among Figure 16 c can quantity, length, diameter, the existence of terminal one or more little rings of ring, and this ring whether be fixed on this install first-class aspect variation.This variation can occur in the flexible apparatus of the support frame with PMMA or other polymeric material.The thickness variable of this crust of the device.The head of this implant and afterbody are placed and put in place and fixing.Ring is regulated and is based on principle previously discussed.Initial insert division is passed in the operation of ring usually, yet this device can have a little ring from the removal of front shell, and an aperture 90 is provided, and shown in Fig. 7 a, is positioned at 180 degree positions of initial incision, by this hole scalable ring or removal ring.As Figure 15 and shown in Figure 16, these rings do not need 360 degree on length, and they are length place incision therebetween also, thereby are convenient to the removal in the later stage.

In another embodiment, this device can have the zone of the increase thickness that the existence owing to thicker part ring 71 forms, this ring is inserted among the hollow shell 30a, can be by constituting (with reference to Figure 17) with same material or a kind of harder material of the wall of this implant such as PMMA.This thicker ring 71 can have different shape of cross sections, preferably meets the shape of cross section of this device and thick local ring 71 more than one can be provided.It can be 10 to 360 degree on chord length.It approximately is the thinnest zone of this device that thereby the end 71a of this local ring is tapered in the ring end portion thickness.The thickness variable of this local ring, thus make that the thicker cross section 75 of this device can be several times of the thinnest section thickness of this device.120 to 180 degree places at the opposite side of this device have one can be similar thicker local ring close on length and thickness, but are not must be like this.These two local rings are interconnection by single line S, shown in Figure 17 a.The astigmatism axle can be adjusted in the later stage, by passing initial incision along a direction or other direction pulling ring, changed the position and they directions with respect to the axis of this device of local ring in this device inner chamber.An independent local ring can have one to connect the ring of an end and the other end, thereby but makes each local ring independent control.As previously described, many different variations all are possible on this theme.Embodiment can adopt any foregoing method in this special minute.An important advantage of this design is that this therapy realizes reversibility easily.This therapy can be replied fully by the exenterate of this device, or refraction effect can partly change as previously mentioned.Self can be replied this adjusting.

In another useful embodiment, the shell of this implantable device is made of polymeric material a kind of biological adaptation, porous, such as the porous polypropylene pipe or such as the material that uses in Dialysis tubing and filter membrane.The characteristics of this porous shell with described similar, comprise that enough pliabilities make the thickness decline of after the biological adaptation material is removed this device.The advantage of porous shell comprises has improved the diffusion of nutritional labeling to the front-angle membrane matrix.

It is shell upper shed in this implant to the method for the diffusion of front-angle membrane matrix that another kind allows to improve nutritional labeling.Opening can be a plurality of, radially or longitudinally, length and variable-width, and be positioned at the front surface or the rear surface of this device.

According to another preferred embodiment of the invention, this implant forms one and is used to the shell such as brinish implant accepting to remove easily.This biological adaptation fluid filled thing is normal saline or sterilized water preferably, accepts but any other acceptable implant of biological adaptation similarly can be used as the fluid filled thing such as hyaluronic acid, hydrogel solution or dextran.As Figure 18 and shown in Figure 19, this implant has one or more compartments, and each compartment all is fluid-tight and independently.Each compartment is filled with the biological adaptation fluid.This compartment can extend along the length of ring, or only partly extends along the length of ring.The cross section of ring can be various geometries, comprises circle, ellipse, rectangle, square and triangle.The diameter of each compartment cross section can change along its length.

This implant 106 comprises a tube-like envelope 107 of being made by a kind of elastomeric material (such as silicone, acrylic acid or urethane polymer).This sheathing material has enough hardness, thereby this device will keep its annular common when plane graph after filling fully, this material also has enough pliabilities, in the time of allowing with fluid filled compartment 117 thickness increase and from compartment 117, flatten during the removal material smooth, respectively shown in Figure 20 a and Figure 20 b.The shell of this device must have enough structural intergrities, intensity, elasticity and ductility and normally keep its annular and expansible.Its combined material can be similar to the material that is adopted when making folding or deformable ophthalmic crystal, such as silicone polymer, urethane polymer and acrylate copolymer, or the material that in soft contact lens, is adopted.If compartment is used for removing from ring, compartment should have and the similar material property of described whole ring wall so.

Referring again to Fig. 7 b, the cross section that the sagittal plane at implant center is passed on the edge of implant 106 can be the elliptical shape that is similar to the implant 30 shown in Fig. 7 b.Each all can improve by changing parameter in the different embodiment shown in Figure 24, thereby provide a large amount of branch embodiment, type such as the combined material of this graft wall, implant ways of connecting, biological adaptation packing material, surface parameter with the cross section of this implant, for example, the cross section by shapes such as annular, square, rectangle, triangle, ellipses forms this implant.The main shaft 39 of cross section of this implant that is similar to the implant 106 of this embodiment is such, that is, the gradient of the cornea arc of the utmost point adapts before it and the cornea, thereby forms the conic section.This angle approximately is 25-35 degree.Compare with the two ends 45,46 of the implant of separating shown in Fig. 7 a, squarely is done at the two ends of implant 106 that should be separately, thereby they can be arranged side by side mutually, and can be by sewing up or bonding such method firmly connect when operation.

This device is suitable for being implanted in the peripheral corneal stroma.Its thickness and geometry are such, that is, it has changed central cornea curvature and has not invaded the central optic zone of cornea after implanting, and does not reduce the diffusion to the nutritional labeling of central cornea.Its size is such, that is, it can easily be embedded in people's the substrate of cornea periphery, and it comprises a biological elastomeric material that adapts to (particularly adapting with eye tissue).Thereby it can change the hollow implant that makes central optic zone flatten smooth by removal fluid from selected compartment by thickness and girth both and form.The size of implant 106 comprises the maximum ga(u)ge (after increasing fully) of about 0.1-0.8mm, the approximately width of 0.4-2.0mm and the whole external diameter of 4-12mm.The thickness of the shell 107 of this implant 106 can be shown in the element of Figure 24 and is changed.

This implant can only comprise one or more compartments, and each all is fluid-tight and is separated with other compartment.Compartment is fluid-tight, but the wall of compartment can be the ring outer wall integral part or be not.If this compartment and shell are separated, as shown in figure 22, then it can increase advantage, thereby promptly not only allows to remove the thickness that fluid reduces whole ring from compartment, thereby and allow compartment itself from ring, to remove to allow that whole ring body amasss further reduces, shown in Figure 22 a to Figure 22 c.The thickness 122 of the ring among Figure 22 c is less than the thickness 121 of Figure 22 b medium ring, and successively, the thickness of the ring among Figure 22 b is less than the thickness of Figure 22 a medium ring.Each compartment is an independent unit.These adjustings are carried out by implanting intracorneal ring.Can have that several and outer wall are isolating to be present in by the compartment in the inner chamber that shell limited of ring.These compartments can change on size and dimension, and extensible 360 degree, but are not must be like this, particularly under differentiated ring thickness rate of needs such as scattered-light situation.

Have another minute of this possible variation of implant of outer wall and interior compartment among the embodiment in explanation, wherein each compartment is a separate unit, the outer wall of ring surrounds the microcapsule or the pearl 125 of many closed volumes that comprise fluid 126 separately, as shown in figure 23.Each small size is separated with diaphragm seal ground, and is full of the fluid of biological adaptation.Outer wall has opening 127,128, makes the outside of ring and comprises replacement fluids between the inner chamber 129 of microcapsule.Each microcapsule can puncture respectively with sharp-pointed instrument or laser, makes fluid flow out from capsule, and the opening that passes outer wall is finally absorbed by cornea tissue.This thickness that causes encircling reduces, thereby makes corneal curvature become precipitous, allows the birefringence result to finely tune.Its advantage is although removed the biological adaptation material from ring, not have material directly to be removed out cornea from ring.This technology has satisfied provides a kind of volume by the adjusting implant to adjust the possible needs of corneal curvature, can optionally get involved with very little operation and carry out.The pharmaceutical field that is applied in of microcapsule is known.The fluid that is injected in the healthy cornea can very fast absorption also be well-known.Fluid injector angle membrane matrix is carried out to help the selfreparing of corneal wound in cataract operation usually.

If the wall of compartment is separated with outer wall as shown in figure 22, so outer wall can by a kind of biological adaptation, porous material (such as the material that uses in hemodialysis tube) constitutes.The characteristics of this porous shell with described similar, comprise that enough pliabilities make the thickness decline of after the biological adaptation packing material is removed this device.The advantage of porous shell comprises has improved the diffusion of nutritional labeling to the front-angle membrane matrix.It is opening 128 or fenestration on the shell of this implant to the method for the diffusion of front-angle membrane matrix that another kind allows to improve nutritional labeling.Opening can be a plurality of, radially or longitudinally, length and variable-width, and can be positioned at the front surface or the rear surface of this device.

Suitable embodiment is to depend on the amount of error of refraction and selected on the type of the size of shape, size, girth, line, biological adaptation packing material and compartment number of variations.This elastic housing 107 also can be by changing shown in the embodiment of the implant of Figure 24 a-24d.This selection comprises:

1. the polymethyl methacrylate (PMMA) that does not have support.

2.PMMA or other hard physiologically acceptable polymer backbone strengthens the interior periphery of this device wall, shown in Figure 24 c.Thicker region 132 shown in Figure 24 c can have the thickness of increase, and it is to be formed by the elastomeric material that constitutes wall; Described thicker region 132 or can be PMMA.

3.PMMA or other hard polymer backbone is strengthened the outer periphery of the wall of this device shown in Figure 21 b.

4. the support of interior neighboring.

5. the ring that compartment arranged and other the also solid filling material of removable biological adaptation use that combines.The compartment 135 of Figure 24 e comprises that fluid and same ring also comprise a solid-state also removable wire filament 125.

Selected device size should be such, inferior to can cosily proofreading and correct (not needing to remove whole ring) by said method to the individual variational excessive correction of reaction of operation or the scope of undercorrection.The type of maximum thickness, girth and support frame is selected before embedding this implant.The ideal embodiment of given preoperative refractive status and other related data is chosen before operation, and this embodiment optionally further operates and decides ideal curvature then.This device is embedded in the peripheral cornea of enough degree of depth, further regulates on retina for the shape of regulating cornea more accurately and the light focusing that will enter in the eyes then.Keratoscope when operation is carried out or automatic keratometer may be helpful.Yet the measurement in the ongoing operation mean curvature of the operation that comprises cornea does not show it is that insight is reproducible in advance.

This device is implanted in and adopts an annular to cut interior 1/2 to the 2/3 cornea degree of depth place of annular flake shape passage that instrument forms open, and this instrument only needs a corneal incision between the little periphery.The radial slot of the about 2mm that begins to the 3.5mm position from CC to 2.5 with scalpel manufacturing one.Only cut in incision on the surface of cornea.Introduce a Suarez dilator in the bottom of otch, thereby produce a little laminar passage.Use vacuum centering guiding device and fix eyeball, an external diameter 8-9mm pass otch be incorporated into laminar channel formation instrument rotation in the laminar passage come to produce at 1/2 to 2/3 cornea degree of depth place one 360 degree around the passage between the cornea periphery.After the channel formation instrument was removed, the tweezers of the scope type of a circle inserted same passage, rotate 360 degree, thereby the tip of these tweezers were exposed from radial slot.One end of this device is inserted in the tweezers, thus closed this device that grips of forceps jaws, and these circular tweezers rotate and put in place gradually up to this device.The instrument that hook is arranged of foregoing circle or other similar instrument also can adopt, to help the placement of this device.The head and the afterbody of this device gather together, and available suture or glue are fixed together.

In a word, implant size, shape, width, outer casing thickness and girth, influence the adjustment or the selection of the factor of corneal curvature refraction results, occur in three specific temporary transient stages:

1. before operation is carried out, the having and be not to adopt the nomogram of the guidance of each variable selection of conduct of coming from the retrospective research development to select of above-mentioned variable and support frame.

2. carry out in the process in operation, the tensioning degree of this implant is optionally adjusted, and adopts the ongoing keratoscope of operation to assist if necessary.

3. postoperative adjusting.The simple postoperative adjusting of carrying out easily can be implemented by this adjustment structure practically, and this adjusting has avoided following the complication of operation once more of most of cornea refraction therapies.This postoperative adjusting can compensate the deficiency of the selection of the preceding implant of operation, the hydration situation of cornea in the process is carried out in the compensation operation, after changing, the hydration status of cornea after the operation causes different corneal curvatures, the change in refraction that wound recovery reaction of not expected around the compensation implant and compensation cause owing to ignorance factor subsequently.This postoperative adjusting can be finished by an elasticity cornea implant that includes a plurality of compartments that are filled with fluid and are separated with other compartment, fluid can be removed from one or more compartments, thereby reduces the thickness of implant and cause corneal curvature to increase.Remove fluid by puncturing compartment selectively, this itself compares the interface that minimally has been upset substrate-implant with removing this device, thereby the wound recovery that will take place when regulating and the consequence of edema are reduced to minimum.This postoperative adjusting looks like those needed additional means of any method of managing to reach the standard of ideal cornea-refraction therapy.If refraction results is undesirable, can take these steps:

A. corneal curvature can flatten by following method.The line of the biological adaptation material in this implant can be connected with larger-diameter line, thereby when the line in this implant was removed, this bigger line was pulled to the position gradually, so thickeied this implant, makes the corneal curvature of front flatten smooth.

B. shown in Figure 25 a and Figure 25 b, if (Figure 25 a) curvature 136 of cornea is peaceful smooth, by puncturing the thickness that compartment 160 reduces to encircle selectively, make fluid flow out, or fluid can be removed by a syringe and pin after operation.Compartment 160 subsides this moment, causes more precipitous corneal curvature 137.Needn't repair the thorn tear,, will can not leak because other compartment is isolating.Optionally can puncture more than one compartment.When correct myopia, adopt present cornea refraction therapy to be difficult to proofread and correct the result of hypermetropia and the excessive correction of myopia takes place.Adopt this device, remove fluid by puncturing one or more compartments selectively, the result of hypermetropia can relatively easily reply.Reduce with confirmable increment by from one or more compartments, removing the fluidic simple ring contraction thickness that causes encircling, therefore allow the fine setting of refraction results.It is difficult technically that fluid is controllably removed from the ring of ports having, because fluidic volume is too small.This last point needs to weigh further.A kind of ring of simple fluid filled in U.S. Patent No. 5,466, has obtained description in 260 by Silvestrini.He has described a kind of expandable ring, and this encircles available saline and injects by the fluid via a nozzle and expand, and this nozzle is a check valve preferably.He has also discussed by a hypodermic needle being inserted this valve opening to come from encircling the probability that the fluidic fluid of interior vacsorb takes out.Yet after this ring was implanted in the cornea, nozzle no longer can be approaching.

A kind of ring of multicellular fluid filled has overcome some problems of following the Silvestrini ring.As the small nozzle of check valve or the manufacturing of valve is very difficult.Fluid is a significant defective via the leakage and the loss of nozzle or valve in long-time, because along with fluid runs off from ring, the thickness of ring reduces, refraction results changes thereupon.Also having a significant technical barrier is to guide the hypodermic needle entry port and remain on that position when fluid extraction.It is thick that ring is typically 0.3mm.When syringe needle was attempted entry port, the previous section of ring must produce compression in that zone and cause thickness to be reduced to being lower than 0.2mm.It is waterproof that nozzle seals, and the resistance of syringe needle entry port is big more, is accompanied by the increase of compression, and the thickness of ring reduces, and increased more to penetrate the danger that is positioned at nozzle ring wall afterwards.And, inject or remove the quite a large amount of fluidic leakage of fluidic process and can make fluidic accurate removal difficulty piercing through nozzle with hypodermic needle.In addition, need the removed Fluid Volume that influence 0.25 to 0.50 dioptric change in refraction too little.Needing the typical Fluid Volume of the such variation of removed influence approximately is 0.002 milliliter, does not stay the space of error.

By contrast, the ring of multicellular fluid filled, each chamber all is an independent unit, does not need a port that has the possible complication of long-term leakage.And the fluidic difficulty that extracts exact magnitude overcomes by puncturing selected compartment, wherein compartment comprised discontinuous quantity by fluid that cornea tissue absorbed.Do not relate to the problem that punctures the position sealing, because each unit all is isolating and fluid-tight.Needless to say, in case ring completes and the sealing of each chamber after, fluid can not reinject.

A typical adjustable implant 106 of the present invention as shown in figure 21.The width of its external diameter 150 is 0.85mm, and whole thickness 151 is 0.3mm, and maximum internal diameter 152 is 0.75mm, and minimum internal diameter 153 is 0.20mm.The implant of this size is expected about 3 diopters of correct myopia.Supposing has 3 compartments, removes fluid and cause flatten 0.15mm or corneal curvature of ring to change 1.5 diopters from whole 3 compartments.For removing fluid from each compartment, it approximately is 0.5 diopter that average diopter changes.Suppose an initial myope, the result can exceed initial refractive 50%, and this hypermetropia is removed by independent fluid and still reasonably controlled.

Causing the treatment of hypermetropia in most cornea refraction therapy excessively is a significant disadvantage.The wound reactivation took place in the time of several years in the radial angle membranectomy, often had gradual hypermetropia.The patient who becomes the hypermetropia symptom after operation is very painful.Therefore most of surgeon adopt the nomogram of attempting to obtain slight undercorrection.

Once relating to the anaclasis keratectomy in the research, finding that the patient is not because their hypermetropia of the eyes of crossing operation is unsatisfied with the gauged chief reason of PRK (first eye supposing them are proofreaied and correct with PRK) to their second eye.This technology is the gauged hypermetropia of excessive correction easily.

In simple an employing of this adjustable implant technology, this device can be used to correction of astigmatism.It is the reason of most of astigmatic situations that the curvature of anterior surface of cornea changes.Convergence of rays does not form a prime focus on more than one plane.Astigmatism depends on the appearance of anchor ring usually, and replaces the spheric curvature of eyes refractive surface.Be correction of astigmatism, the degree that the specific region of cornea is need be than other regional correction bigger.The specific dimensions that is positioned at implant and the compartment of shape can be arranged, and wherein compartment has increased the size of the appropriate area of ring with respect to other zone, as shown in figure 26.The solid section of this implant (its cross section is shown in Figure 26 b) has a fixed thickness 138.The part of the thickness with increase by 139 of this implant should be corresponding to the gauged more zone of the needs of cornea.Replace changing the size and dimension of compartment, the wall of this ring can have different thickness 140.The combination of different wall thickness and variable compartment size also can be adopted.Puncture these compartments selectively and adjust result in the astigmatism correction.Compartment can change on number, length, diameter, volume and shape of cross section.On the flexible implant of the support frame that can have a PMMA or other polymeric material, also can change.

Therefore can recognize by adopting the present invention, can avoid the shortcoming of traditional refractive surgery therapy, such as: 1) the gradual hypermetropia of radial angle membranectomy.Hypermetropia in any refraction therapy is a common worse result, because the patient does not have clearly vision and because hypermetropia more is difficult to proofread and correct in any scope.Described therapy is particularly suited for regulating the refraction results of hypermetropia; 2) irreversibility of radial angle membranectomy and laser ablation operation; 3) operation technique of the central optical axis of the potential probability that forms cicatrix and substrate muddiness after the laser ablation therapy is arranged; 4) have together complication such as cataract and glaucomatous situation under, need life-time service steroid drop; 5) rollback of laser ablation therapy, the particularly art of hands again subsequently; 6) actual spheric the reducing of employing RK and laser ablation, it is not normal that this reduces to cause increasing image; 7) intrusion of on-the-spot laser in the keratomileusis; Precision and predictable shortage when 8) adopting at present all therapies; 9) may need in the prior art interior corneal ring (ICR) repeat shift out and implant, this may cause the shearing of cornea peripheral channel thin slice, and is accompanied by the respective change of effect and the formation of cicatrix.

About last a bit, regulate the method for the thickness of the ring of implanting and described in the prior art.These methods only just in implantation process the thickness of adjustable ring discuss, rather than after operation.The trial of the thickness of adjustable ring is of great use after corneal curvature is stable basically.The adjusting of the device of Miao Shuing in the prior art will need the rotation of ring, and this causes the shearing at corneal ring interface.Thereby the rotation that allows indivedual loop sections ground to overlap more or less to increase or reduce the ring of ring thickness is an example.Near this shearing of the cornea tissue ring can a kind of unpredictalbe mode change corneal curvature, causes having the more cicatrix of unpredictalbe long-term refraction effect.Among the described in this article embodiment, the adjusting of the thickness of ring only has very little interference to surrounding tissue.On the characteristic of regulating, rotatablely moving of ring aspect wherein should not contact with cornea tissue with respect to cornea by ring.For clearly illustrating " rotatablely moving ", must be similar to the rotation that will encircle the needed ring of passage between interposed layer at first by reference class.Rotatablely move cornea-ring interface multilated along with the ring of implanting.Among the described in this article embodiment, cornea-ring interface not multilated basically.Certainly, along with reducing of ring thickness, surrounding tissue will have a small variation.In a word, make the thickness of ring slightly reduce not only can more easily carry out, and have more predictable discrete effect by described adjusting.

Doctor R.Eiferman describes in the magazine of " refraction and operation on cornea ": " if we can regulate the quantity and the control biological effect of the tissue that increases or reduce from cornea to cornea, we can optimize refractive surgery so." Perfected process of this control biological effect is a minimally Interference angle membrane tissue, thereby minimally stimulates wound to restore reaction.

Doctor K.Thompson asks in same magazine: " for the refractive surgery technology; it is impossible walking around the restorative indefinite effect of corneal wound fully? " this is impossible for initial cornea refraction therapy, but adjustable device of the present invention makes and can avoid the adjusting of the restorative indefinite effect of corneal wound to become possibility by minimally Interference angle membrane tissue.

Most refractive surgery therapy adopts nomogram to calculate needed correction, and can not explain the indefinite reaction of individual birefringence operation fully.Usually, a kind of have the improved therapy of whole Unpredictabilities to be used to proofread and correct remaining error of refraction, is accompanied by the increase of complication ratio cicatrization.The various embodiment of this device allow such fact, promptly, individual tissue reaction to the correcting value that calculates may not be foreseeable fully, and in when operation with the more important thing is at cornea hydration status and wound and restore the time in later stage that reaction has been stablized, by simple removal ring or alternate collar or puncture compartment selectively and allow easily to regulate from this device.The characteristic minimally of these adjustings disturbs implant-corneal interface (not resembling shifting out of ICR) and therefore is expected to have than the more foreseeable effect of the implantation of this implant itself, and this implant has caused the wound littler than present therapy (such as RK and PRK) to restore reaction.In addition, when correct myopia, the result who adopts present any cornea refraction therapy to proofread and correct hypermetropia is difficult, and the excessive correction of myopia takes place.According to present preferred embodiment of the present invention, the result of hypermetropia can relatively easily reply by the removal of sewing up.Typically, in the most cornea refraction therapy that is used for myopia, the doctor is conceived to slight undercorrection, because wish to avoid the result of hypermetropia.It is easy to adopt implant of the present invention to regulate the result of hypermetropia, this makes that the doctor can be conceived to proofread and correct fully, therefore obtain whole benefits of nomogram, cause in addition not this implant adjusting and have the patient's of desired refraction results higher percent.Doctor even can select slight excessive correction to regulate subsequently.

Suppose that the individual changes the reaction of any cornea refractive surgery therapy, even the nomogram of " perfection " can not cause reliable foreseeable result to specific individual, simply, safety, to regulate otherwise effective technique be desired to corneal curvature, thereby and preferably this adjusting answer minimally to disturb surrounding tissue to create conditions for foreseeable effect.This adjusting also should be to finish easily period with the stable a certain operation back of the factor that influences the corneal curvature variation after this implant is implanted.This implant in its each embodiment can be regulated thickness easily, when implanting, easily regulate, and the more important thing is, in a plurality of chances after this, regulate by the biological adaptation packing material of from the device of this implantation, removing discrete number simply, thus the fine setting of permission refraction results.

In a word, when adopting the described adjustable implanted prosthetics correction of refractive error of a preferred embodiment, initial coarse correction, insufficient adjusting or even the removal of last line all can easily remedy by removing this implant itself, or be more preferably, if this point can reach, then allow it stay the original place and consider that simultaneously other refraction therapy performs the operation such as laser ablation.

Should be appreciated that the front is a purpose for description and interpretation to the description of various embodiment of the present invention, but be not intended to the present invention is limited to the mode of reality as described herein and the precise forms of device.Therefore should be understood that, under the situation that does not break away from purport of the present invention as claimed in claim, can make variation by those persons skilled in art.

Claims

1. corneal ring, it comprises:

One forms the tubular part of ring, and this tubular part comprises a kind of biological adaptation material;

One line in this tubular part cavity, this line extends along at least a portion of the length of this tubular part.

2. corneal ring according to claim 1 is characterized in that, it also comprises at least one additional line.

3. corneal ring according to claim 1 is characterized in that this tubular part comprises a kind of flexible material.

4. corneal ring according to claim 1 is characterized in that, this line comprises a kind of material of choosing from the material group that is made of polymethyl methacrylate, nylon, single Silene (mersilene) and polypropylene.

5. corneal ring according to claim 1 is characterized in that, this tubular part comprises one at least along the web frame of the part of the length of this tubular part.

6. corneal ring according to claim 1 is characterized in that this tubular part is porous.

7. corneal ring according to claim 1 is characterized in that, this tubular part comprises a plurality of apertures that are used between the outside of the cavity of this tubular part and this tubular part replacement fluids.

8. corneal ring according to claim 1 is characterized in that, this tubular part comprises that one is used for the aperture near cavity.

9. corneal ring according to claim 1 is characterized in that the length of this line approximates the length of this tubular part greatly.

10. corneal ring according to claim 1 is characterized in that, this line has at least one thicker part.

11. corneal ring according to claim 1 is characterized in that, this line is folded in this tubular part.

12. corneal ring according to claim 1 is characterized in that, the periphery of the cross section of this line has corner angle.

13. corneal ring according to claim 1 is characterized in that, the periphery of the cross section of this line is crooked.

14. corneal ring according to claim 1 is characterized in that, this line comprises a labelling at least one end.

15. corneal ring according to claim 1 is characterized in that, the thickness of this line is adjustable, and this line comprises a pair of complementary ring that separates.

16. corneal ring according to claim 1 is characterized in that, this line comprises the device that is used for firmly grasping this line.

17. corneal ring according to claim 16 is characterized in that, this grasp device comprises a little ring at least one end of this line.

18. a method that is used for regulating the eyes corneal curvature, this method may further comprise the steps:

In cornea, make a radial slot;

In this incision, between the thin layer of cornea tissue, form a circular passage, described passage extends around the vision area of cornea;

One end of one tubulose corneal ring is inserted in this otch, and this corneal ring is included in the solid filling material in the inner chamber;

Moving this corneal ring gradually along this circular passage inserts fully up to this corneal ring.

19. method according to claim 18 is characterized in that, this solid filler comprises one material that extends along the part of this corneal ring at least at least.

20. method according to claim 19 is characterized in that, it also comprises the long-pending step of radial cross-section of regulating this corneal ring.

21. method according to claim 19 is characterized in that, it also comprises the step of the thickness of at least a portion of regulating this corneal ring.

22. method according to claim 21 is characterized in that, this regulating step comprises at least one that removes in the single line at least.

23. method according to claim 21 is characterized in that, this regulating step comprises with a thicker line and replaces in the single line at least at least one.

24. method according to claim 21 is characterized in that, this line has a thicker part branch, and this regulating step comprises and move this line, thereby this thicker part is shifted in corneal ring.

25. method according to claim 21 is characterized in that, the thickness scalable of this line, and this line comprises a pair of complementary ring that separates.

26. method according to claim 21 is characterized in that, this regulating step may further comprise the steps:

On at least one in single line at least, connect first end and second end of described line, to form a wire loop; And

This wire loop of tensioning.

27. method according to claim 26 is characterized in that, this regulating step comprises the wire loop that cuts this tensioning.

28. method according to claim 21 is characterized in that, this regulating step may further comprise the steps:

In this tubular part, connect first end and second end of described tubular part, to form a tubular ring;

This tubular ring of tensioning.

29. a method that is used for regulating the eyes corneal curvature, this method may further comprise the steps:

In operation for the first time, in cornea, make a radial slot;

One end of one tubulose corneal ring is inserted in this otch, and this ring is included in the line of at least one solid material in the tubular cavity in;

Moving this corneal ring gradually along this circular passage inserts fully up to this corneal ring; And

In operation for the second time, regulate the thickness of this ring by mobile single line at least wherein.

30. method according to claim 29 is characterized in that, it also is included in the step of regulating the thickness of this corneal ring at least a portion in the operation for the first time.

31. method according to claim 30 is characterized in that, this regulating step comprises at least one that removes described line.

32. method according to claim 30 is characterized in that, this regulating step comprises with a thicker line and replaces in the described line one.

33. a corneal ring comprises:

One forms the tubular part of ring, and this tubular part comprises:

One biological adaptation material;

The inner chamber of a plurality of fluid filled, extend along at least a portion of the length of this tubular part in each chamber.

34. corneal ring according to claim 33 is characterized in that, the fluid at least one of described chamber comprises saline.

35. corneal ring according to claim 33 is characterized in that, the fluid at least one of described chamber comprises gel.

36. a method that is used for regulating the eyes corneal curvature, the method comprising the steps of:

In cornea, make a radial slot;

One end of one tubulose corneal ring is inserted in this otch, and this corneal ring comprises the compartment of a plurality of fluid filled; And

37. method according to claim 36 is characterized in that, at least one in the described compartment and this tubular part are separated.

38. method according to claim 36 is characterized in that, it also comprises the long-pending step of radial cross-section of at least a portion of regulating this corneal ring.

39., it is characterized in that this regulating step comprises at least one at least some fluids of removing in the described compartment according to the described method of claim 38.

40. method according to claim 36 is characterized in that, it also comprises the step of the thickness of regulating this corneal ring at least a portion.

41. method according to claim 36 is characterized in that, it also comprises this step, that is, and and in operation for the second time, by from least one compartment, removing the thickness that fluid is regulated this corneal ring.