RU2421195C1 - Method of initial keratoconus treatment - Google Patents

Abstract

FIELD: medicine. ^ SUBSTANCE: invention relates to medicine, namely to ophthalmology and can be applied in treatment of progressing keratoconus at its initial stage. Method consists in injection introduction into perylimbal zone of dispersed biomaterial Alloplant. Alloplant is preliminarily diluted in physiological solution in ratio 30 mg of biomaterial per 0.5-1.5 ml of physiological solution with addition of 0.5 ml of dexamethasone. Injections are made under conjunctiva and Tennon's capsule in 4-6 points around limb in each eye 1 time per 6-12 months. ^ EFFECT: method makes it possible to increase efficiency of keratoconus treatment without risk of trauma and complications. ^ 1 ex

Description

The invention relates to medicine, namely to ophthalmology, and can be used in the treatment of progressive keratoconus at its initial stage.

Keratoconus is a progressive, often bilateral, corneal disease characterized by a decrease in its strength, central thinning and subsequently scarring. The pathological process with keratoconus begins with damage to the epithelium, the Bowman membrane and, gradually progressing, captures the deeper layers of the cornea (stroma, descemet membrane), leading to degeneration, thinning, ecstasy of the cornea and, finally, to acute keratoconus and scarring in the center of the cornea ( Avetisov SE IV Russian symposium on refractive and plastic eye surgery. Collection of scientific articles, p.3).

The initial keratoconus is characterized by changes in the anterior cornea due to degeneration of the basal cells of the corneal epithelium, the occurrence of folding, defects in the bowman's membrane. The most characteristic biomicroscopic early signs of keratoconus are rarefaction zones of the stroma symmetrically located in the lower inner quadrant for the right eyes and the lower outer quadrant for the left - a symptom of a dying star or a symptom of fireworks. (Kasparov A.A. "Refractive surgery and ophthalmology", 2002, v.2, No. 3).

A known method of drug treatment of keratoconus (RF patent No. 2171659, IPC A61F 9/00, publ. 08/10/2001). According to the method, they are instilled twice at the same time in the conjunctival cavity, 1-2 drops of a solution of leukinferon - 500 mU are dissolved in 2 ml of distilled water. The course of treatment is at least 10 days.

This method has a temporary effect on the time of conservative treatment. Subsequently, keratoconus progresses.

There is a method of excimer laser surgical treatment of initial keratoconus, comprising a combination of photorefractive keratectomy and phototherapeutic keratectomy (RF patent No. 2146119, published on March 10, 2001). By excimer laser action on the anterior layers of the cornea, a photoinduced fibrocellular membrane is formed, which can later serve as a matrix around which the lamellar structure characteristic of the normal cornea is synthesized and remodeled, inhibiting or preventing the further development of keratoconus in the postoperative period.

The disadvantages of the method are:

- a laser injury to the cornea initiates a pronounced inflammatory reaction that requires additional medical treatment;

- An inadequate inflammatory reaction that occurs under the influence of laser radiation is a risk factor in the development of dry eye syndrome, aggravating the course of the underlying disease;

- oxidative stress in the cornea arising under the influence of laser radiation can stimulate the excessive formation of inflammatory mediators, causing fibrotization and vascularization of the cornea, reducing visual acuity;

- the formation of scarred tissue in the projection of excimer laser exposure, which reduces the transparency of the cornea.

A known method of treating keratoconus by implanting introstromal corneal segments of Ferrara. Implantation is carried out in a 5 mm zone at a depth of 2/3 of the cornea thickness, focusing on the localization of the apex of the keratoconus and the boundary line of corneal deformation (Dvoli M.P., Tsiptsadze I.A., Sibriladze B.V., Gibradze K. Fedorov readings, 2004. New technologies in the treatment of corneal diseases. Scientific-practical conference, p.11). The disadvantage of this method is the long-lasting edema of the cornea, the development of corneal astigmatism.

Closest to the proposed one is a method of treating initial keratoconus (RF patent No. 2225141, IPC A61F 9/007, published May 27, 2008), according to which the Bioplast biomaterial pre-impregnated in immunotropic is introduced paralymbally into the corneal ectasia projection. Superlimf. A strip of biomaterial is introduced through a conjunctival incision at a distance of 3 mm from the limbus.

The disadvantage of this method is its invasiveness and the risk of postoperative complications.

The objective of the invention is to increase the effectiveness of the treatment of initial keratoconus without the risk of trauma and complications.

The problem is solved by the method of treatment of the initial keratoconus, which consists in introducing biomaterial into the perilimbal zone, in which, in contrast to the prototype, injected dispersed Alloplant biomaterial is injected, which is previously diluted in physiological solution in a ratio of 30 mg of biomaterial to 0.5-1.5 ml of saline with the addition of 0.5 ml of dexamethosone, and injections are performed under the conjunctiva and tenon capsule at 4-6 points around the limbus in each eye 1 time in 6-12 months.

The Alloplant biomaterial used in the proposed method, developed at the All-Russian Center for Ophthalmic and Plastic Surgery and approved for wide clinical use (TU No. 42-2-537-2006 of the Ministry of Health of Russia) has unique regenerative properties and extremely low antigenic properties. The Alloplant biomaterial, crushed to a powder state (dispersed), has the ability to attract and concentrate macrophage cells and stimulate their maturation, due to which it becomes possible to correct fibrotic and degenerative-dystrophic changes in tissues (RF patent No. 2189257, IPC A61L 27/00, published on September 20, 2002).

The Alloplant Dispersed Biomaterial (DBMA) produced by the All-Russian Center for Ophthalmic and Plastic Surgery meets all the requirements of the task for treating keratoconus:

- convenience, safety and painlessness of administration;

- prolonged effect on the cornea;

- low antigenic properties;

- prevention of opacities, improvement of the optical properties of the cornea, stimulation of full regeneration;

- improvement of local immunity, significantly reducing the likelihood of infectious complications.

The experimental and clinical material accumulated by the authors makes it possible to substantiate the following mechanisms of the therapeutic effect by the method of perilimbal administration of DBMA: microcirculation and activation of the processes of reparative regeneration are activated, which contributes to the correction of the optical properties of the cornea. Correction of the optical properties of the cornea is noted by two criteria: an increase in visual acuity and an increase in the total thickness of the cornea. The total thickness of the cornea indicates the degree of thinning of the cornea. It is determined by the sum of measurements of the thickness of the cornea at 13 points using a keratopachometer.

Activation of microcirculation processes and stimulation of reparative regeneration processes in the cornea were studied in the experimental rabbit corneal burn zone. It has been proven that perilimbal administration of DBMA activates macrophage infiltration processes and thereby helps to restore the structure of the cornea. In addition, the introduced DBMA contains all the components of the extracellular matrix: cologen, hyporan sulfate, and the proteoglycan complex. The indicated components introduced into the perilimbal space create a depot of metabolites necessary for the cornea, which, with the participation of macrophages, are actively involved in metabolic processes, contributing to the normalization of the corneal biochemism. As a result, visual acuity improves and the total thickness of the cornea increases.

The proposed new set of essential features of a method for treating keratoconus is not obvious, providing the criterion of "Inventive step".

The method is as follows.

A solution of DBMA for injection is prepared: 1.0-1.5 ml of saline with the addition of 0.5 ml of dexamethosone is injected into a sealed sterile vial with 30 mg of biomaterial. The surgical field is treated with an alcohol solution. A blepharostat is placed on the eyelids. 5% lidocaine solution and 0.25% chloramphenicol solution are instilled. The prepared DBMA solution is injected by injection under the conjunctiva and tenon capsule around the limb, departing from it 5 mm: under the upper eyelid at 2-3 points and under the lower eyelid at 2-3 points. The amount of injected DBMA solution is 1.0-1.5 ml. Injections are thus administered to each eye. At the end of the procedure, an instillation of a 0.25% solution of chloramphenicol is carried out. An aseptic blindfold is applied to the eyes.

Clinical example:

Patient W., 26 years old. Diagnosis: keratoconus stage 1-2 of both eyes. Sick for 10 years, treatment was not carried out.

Upon enrolment:

Vis OD 0.07; with a correction of 0.5-0.6

Vis OS 0.06; with a correction of 0.5-0.6

Keratoconus index: OD 0.48; OS 0.47

The total thickness of the cornea OD - 7597 microns; OS - 7445 μm.

The treatment was carried out according to the proposed method. Used for injection DBMA diluted in saline in the ratio: 30 mg of biomaterial per 1.5 ml of saline with the addition of 0.5 ml of dexamethosone.

After processing the surgical field and instillation, injections were made with the prepared DBMA solution under the conjunctiva and tenon capsule around the limbus, 5 mm departing from it. Injections were carried out in each eye at 4 points: 2 under the upper eyelid and 2 under the lower eyelid. Then, a 0.25% solution of chloramphenicol was installed, an aseptic blindfold was applied to the eyes.

After treatment after 6 months:

Vis OD 0.2; with correction of 0.6-0.7

Vis OS 0.2; with correction of 0.6-0.7

Keratoconus index: OD 0.43, OS 0.41

The total thickness of the cornea OD - 7618 microns; OS - 7623 microns.

Thus, as a result of treatment, the patient's visual acuity improved and the total thickness of the cornea increased, which indicates the effectiveness of keratoconus treatment.

In the All-Russian Center for Ophthalmic and Plastic Surgery, 65 patients from 17 to 52 years old with an initial stage of keratoconus were observed and treated according to the proposed method. Of these, 15 people underwent a repeated course of treatment after 6-12 months for 2-3 years.

The treatment was carried out on an outpatient or inpatient basis. The patient was discharged for 2-3 days. In the postoperative period, antibiotic and dexamethosone installations were performed. All patients showed an increase in visual acuity, an increase in the total thickness of the cornea, a decrease in the keratoconus index.

Thus, the proposed invention improves the treatment of keratoconus without the risk of trauma and complications.

Claims (1)

A method of treating the initial keratoconus, which consists in introducing the biomaterial into the perilimbal zone, characterized in that the dispersed Alloplant biomaterial is injected, which is previously diluted in physiological solution in a ratio of 30 mg of biomaterial to 1.0-1.5 ml of saline with the addition of 0.5 ml of dexamethosone, and injections are performed under the conjunctiva and tenon capsule at 4-6 points around the limb in each eye 1 time in 6-12 months.