RU2268690C2 - Method for fixing posterior-chamber artificial lens at c-shaped supporting elements - Google Patents

Abstract

FIELD: medicine, ophthalmology.

SUBSTANCE: one should implant artificial lens, perform development of layer-by-layer scleral fragments, withdraw supporting elements onto the surface of scleral channel through incisions of sclera and vascular membrane followed by applying supporting elements along patient's limbus. Then comes fixation of lenticular supporting elements sclerally in projection of ciliary groove being beyond incision area of sclera and vascular membrane. Application of the method provides reliable and stable IOL fixation in patient's eye, exclude the chance for IOL's optic part inclination and, also, decreases the chance of inflammatory complications and secondary glaucoma.

EFFECT: higher efficiency.

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Description

The invention relates to medicine, namely to ophthalmology, and can be used to correct capsuleless aphakia by implantation of a posterior artificial lens of the eye.

A known method of suture fixation of the posterior chamber intraocular lens (IOL) to the iris for correcting aphakia in the absence and defects of the capsular support (Price FW, Whitson WE Visual results of suture-fixated posterior chamber lenses during penetrating keratoplasty. - Ophthalmology. - 1989. - V. 96. - P.1234-1239). The disadvantage of this method of suture fixation of the posterior chamber IOL is chronic irritation of the uveal tissue, which increases the likelihood of developing macular edema of the retina and secondary glaucoma.

The closest technical solution is the method of transscleral suture fixation of supporting elements of the posterior chamber IOL (Hu BV, Shin DN, Gibbs KA, Hong YJ Implantation of posterior chamber lens in the absence of capsular and zonular support. - Arch. Ophthalmol. - 1988. - V. 106. - P.416-420; Lewis JS Ab externo sulcus fixation. - Ophthalmic. Surg. - 1991. - V.22. - P.692-695).

The IOL implantation technique consists in the formation of layered scleral flaps, 10-0 polypropylene filaments are drawn ab interno or ab externo through the deep layers of the sclera and the iridociliary sulcus at two opposite points, the ends of the threads are tied to the supporting elements of the posterior chamber IOL, then implanted into the IOL the camera is centered by pulling on the threads and fixed to the sclera.

One of the significant drawbacks of this method is the possibility of dislocation of the IOL into the vitreous body due to the failure of the transscleral suture due to various reasons: untying the suture, slipping of the suture from the support element, natural biodegradation of the polypropylene suture or as a result of injury (Assia EI, Nemet A., Sachs D Bilateral spontaneous subluxation of scleral-fixated intraocular lenses. - J. Cataract Refract Surg. - 2002. - V.28. - P.2214-2216. Lee SC., Chen FK., Tseng SH., Cheng HC. Repositioning a subluxated sutured intraocular lens in a vitrectomized eye. - J. Cataract Refract Surg. - 2000. - V.26. - P.1577-1580). Another disadvantage of the method is the possibility of tilting the IOL due to unstable fixation at two points and rotation along the axis of fixation, as a result, astigmatism develops and the achieved postoperative visual acuity decreases (Berger RR, Kenyeres A. Repositioning a tilted ciliary-sulcus-fixated intraocular lens. - J. Cataract Refract Surg. - 1995. - V.21. - P.497-498). It is also obvious that the micromotions of the supporting elements and the transscleral suture irritate the ciliary body, thereby increasing the likelihood of inflammatory complications and secondary glaucoma.

Based on the disadvantages of the prototype, we set the task to develop a method for fixing the posterior chamber IOL with the C-shape of the haptic in aphakia with the absence of capsule support, which allows:

- provide reliable and stable fixation of the IOL inside the eye;

- reduce the risk of dislocation of IOL in the vitreous body in the remote postoperative period;

- eliminate the likelihood of tilting the optical part of the IOL;

- reduce irritation of the choroid, thereby reducing the likelihood of inflammatory complications and secondary glaucoma.

To accomplish this task, we have proposed a method for fixing a posterior chamber artificial lens, including the formation of layered scleral flaps and implantation of an artificial lens, characterized in that the supporting elements of the artificial lens are brought to the surface of the scleral bed through the incision of the sclera and choroid in the base of the scleral bed in the projection of the iridociliary groove fixed in the layers of the sclera (intrascleral).

Figure 1 and figure 2 shows the stage of formation of scleral flaps (1) and incision (2) of the sclera and choroid in the scleral bed (3). In Fig.3 and Fig.4 - an artificial lens (4) is implanted in the posterior chamber, the supporting elements (5) are displayed in the scleral bed and fixed intrascleral.

The method is as follows. In the upper sector, a cut of the cornea is 5.5-6.5 mm, depending on the diameter of the optical part of the IOL. In the upper and lower sectors produce a section of the conjunctiva 7-8 mm long. Then the vessels are coagulated with episclera and scleral flaps of rectangular shape are formed with dimensions 6 × 3 to 1/3 of the thickness of the sclera with the base to the limb. In the scleral bed, departing 1 mm from the posterior surgical limb and 0.5-1.0 mm from the left wall of the scleral bed in the upper sector and from the right wall - in the lower sector, sequential sections of the sclera and choroid are made in the projection of the iridociliary groove parallel to the limb of length 2.5-3.0 mm. Through the incisions of the sclera and choroid, two polypropylene filaments are inserted inside at the end of the V-shaped pusher parallel to the posterior surface of the iris until visualization in the pupil area. Then the polypropylene filaments are removed from the eye through a corneal incision using tweezers for tying the filaments. Polypropylene yarns are tied to the supporting elements of the IOL, respectively, the upper thread to the upper supporting element, the lower to the lower supporting element. Then the IOL is implanted in the posterior chamber and centered by pulling on the threads. By lightly pulling the conductor thread, the supporting elements are alternately brought to the surface of the scleral bed and fixed to the sclera using two 8-0 interlock sutures. On sections of the sclera (in the projection of the iridociliary sulcus) impose 1 nodal sealing suture 8-0. Superficial scleral rags are put in place and fixed with three interrupted sutures 8-0. Suture the conjunctiva. The corneal incision, if necessary, is sealed with one nodal suture or a continuous seam according to Pierce (nylon, 10-0). Under the conjunctiva, a solution of an antibiotic and dexazone is administered.

To study the effect of the intrascleral arrangement of supporting elements of the posterior chamber IOL on the tissue of the eyeball, an experimental study was conducted. The safety of our proposed method of intrascleral fixation of support elements was studied in an experiment on 8 rabbits of the breed "Chinchilla."

Operation Technique. In the upper sector, a conjunctiva was cut 7 mm long and it was separated. Then, the episclera vessels were coagulated and a scleral flap of rectangular shape 4 × 3 mm in size was formed on 1/3 of the sclera thickness with the base to the limb. At 12 hours, corneal paracentesis was performed, a visiton was introduced into the anterior chamber, and anterior capsulotomy was performed. The corneal incision was enlarged to 6 mm, the lens was removed, the lens masses were aspirated using a Simcoe cannula. A rear-chamber IOL of polymethylmethacrylate with a C-shape support element was implanted. 5-6 8-0 nodal sutures were placed on the cornea. In the scleral bed, departing 1 mm from the limb, sequential sections of the sclera and choroid were made in the projection of the ciliary body parallel to the limb 2.5 mm long. Through an incision in the sclera and choroid, the upper supporting element of the IOL was brought to the surface of the scleral bed and fixed to the sclera using two 8-0 interrupted sutures. The scleral incision in the projection of the ciliary body was sealed with one 8-0 nodal suture. The superficial scleral flap was put in place and fixed with three 8-0 interrupted sutures. 8-0 nodal sutures were placed on the conjunctiva. The remains of the visiton were washed out of the anterior chamber and the anterior chamber was restored with physiological saline. A solution of gentamicin and dexazone was administered under the conjunctiva.

A biomicroscopic examination of the eyes of rabbits after surgery revealed a moderate eye injection, conjunctival hyperemia, and corneal edema in the area of the surgical incision after one day. Hyperemia of the iris was noted, exudate in the anterior chamber in the pupil. Within 4-5 days, the transparency of the cornea was restored, the exudate in the pupil resolved, the moisture of the anterior chamber became transparent. By 6-7 days after surgery, the eyes completely calmed down. In the postoperative period (up to 6 months), the transparency of the cornea and the correct position of the IOL were maintained in all animals. No changes in the fundus during the entire observation period were detected. Within 2 weeks, 1, 3, and 6 months after the operation, the animals were removed from the experiment by the air embolism method. Eyes were enucleated for histopathological examination.

Pathological examination. Paraffin sections are made according to standard methods. Slices were carried out through the fixation zone in the sclera of the supporting element of the IOL. The thickness of the slices is 7-8 microns. Hematoxylin-eosin stain.

Figure 5 presents the microphoto plot of the sclera and ciliary body 2 weeks after surgery (magnification × 85). In the thickness of the sclera, a transverse section of the supporting element of the IOL is determined (indicated by a thick arrow). Moderate swelling of the sclera tissue and episclera around the supporting IOL element, violation of the laminar structure of the sclera in the operative access zone (indicated by thin arrows) are noted. Figure 6 presents the microphoto of the same histological preparation at high magnification. Around the supporting element, single lymphocytes, white blood cells, macrophages and a transverse section of suture material are determined. There is a slight violation of the laminar structure of the sclera in the area of the wound channel of the operational access. In tissues in contact with the supporting element, necrotic changes are not detected (magnification × 350).

Figure 6 presents the microphoto of the site of the sclera and ciliary body 6 months after surgery (magnification × 85). The correct laminar structure of the sclera is noted. In the thickness of the sclera in the projection of the ciliary body, a transverse section of the supporting element of the IOL is determined (indicated by an arrow). On Fig presents microphoto of the same histological preparation at high magnification. Around the IOL support element, the formation of a thin capsule-like environment from compacted unchanged scleral fibers is determined (magnification × 350). There are no signs of an inflammatory reaction and structural changes in the sclera and ciliary body.

Thus, in the early stages of the experiment, a moderate tissue and cell reaction to surgical trauma was revealed in the form of local swelling of the sclera and episclera tissue, and scanty lymphocytic leukocyte infiltration.

In the long term of the experiment, histological studies revealed no cellular and structural changes in the sclera and ciliary body. The restoration of the correct laminar structure of the sclera is noted. The sclera is intact with respect to the supporting element of the IOL located in its layers.

The operation has been introduced into clinical practice.

Example. Patient X., 19 years old. Diagnosis: OD - Consequence of a penetrating wound of the cornea, corneal scar, Afakia. Secondary compensated glaucoma.

OS - Healthy. Visual acuity of the right eye of 0.01 sec. + 10 ^D = 0.1; left eye 1.0.

In 1990 (at the age of 6) he received an injury to his right eye with a branch. Afakia - 13 years old. Contact correction does not tolerate.

A 6.5 mm long corneal tunnel incision was formed under local anesthesia in the upper sector. In the upper and lower sectors, a conjunctiva 7 mm long was cut. Then, the episclera vessels were coagulated and rectangular scleral flaps 6 × 3 mm in size were formed on 1/3 of the sclera thickness with the base to the limb. In the scleral bed, departing 1 mm from the posterior surgical limb and 1.0 mm from the left wall of the scleral bed in the upper sector and from the right wall in the lower sector, successive sections of the sclera and choroid were made in the projection of the iridociliary groove parallel to the limb of length 2, 5-3.0 mm. Through the incisions of the sclera and choroid, two polypropylene filaments are inserted inside the end of the V-shaped pusher parallel to the posterior surface of the iris until visualization in the pupil area. Then the polypropylene filaments were removed from the eye through a corneal incision using tweezers for tying the filaments. Polypropylene yarns were attached to the supporting elements of the IOL, respectively, the upper thread to the upper supporting element, the lower to the lower supporting element. Then, the IOL was implanted into the posterior chamber and centered by pulling on the threads. By lightly pulling on the conductor thread, the supporting elements were alternately brought to the surface of the scleral bed and fixed to the sclera using two 8-0 interlock sutures. On the scleral sections (in the projection of the iridociliary sulcus), 1 nodal sealing suture 8-0 was applied. Superficial scleral flaps were put in place and fixed with three 8-0 interrupted sutures. Stitched on the conjunctiva. The corneal incision was sealed with a continuous seam according to Pierce (nylon, 10-0). Under the conjunctiva, a solution of an antibiotic and dexazone is introduced. We did not observe complications during and after the operation.

The postoperative period was marked by a reactive course. Visual acuity 1 month after implantation of IOL 0.2 without correction, IOP 18 mm Hg, the position of the IOL is correct, in the center.

Our proposed method for intrascleral fixation of supporting elements of the posterior chamber IOL allows us to solve the tasks:

- provide reliable and stable fixation of the IOL inside the eye;

- reduce the risk of dislocation of IOL in the vitreous body in the remote postoperative period;

- eliminate the likelihood of tilting the optical part of the IOL;

- reduce irritation of the choroid, thereby reducing the likelihood of inflammatory complications and secondary glaucoma.

Claims (1)

A method for fixing a posterior chamber artificial lens with a C-shape of support elements, including implantation of an artificial lens and fixing lens support elements in the sclera in the projection of the ciliary sulcus, characterized in that the formation of layered scleral flaps, the removal of support elements on the surface of the scleral bed through the incision of the sclera and vascular shell, laying supporting elements along the limb and fixing them with sutures to the sclera outside the incision area of the sclera and choroid.

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