RU2278656C1 - Viscoelastic for protection of intraocular eye tissues - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: claimed viscoelastic based on 1.5-2.5 % methylcellulose contains additionally 0.0125-0.025 % dipivephrin hydrochloride solution and 0.0005-0.01 % of benzalconium chloride as stabilizer.

EFFECT: viscoelastic for prevention of eye tissues during intraocular interferences.

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Description

The invention relates to medicine, in particular to ophthalmic surgery, and can be used for intraocular surgery to protect intraocular tissues from surgical trauma and reduce complications.

It is known to use viscoelastics based on methylcellulose in intraocular operations, for example, cataract extraction and phacoemulsification to protect the intraocular tissues of the eye, especially the corneal endothelium (V.A. Povolotskaya, L.A. Chaika, Ophthalmosurgery, 1997, No. 1, pp. 56-61) . However, the use of even the most effective of viscoelastics visited, which includes methyl cellulose, dissolved in saline with phosphate buffer, has certain disadvantages. In particular, it is not uncommon that the early postoperative period is complicated by increased ophthalmotonus, which is a consequence of mechanical obstruction of the trabecular network by viscoelastic, which in some cases contributes to the development of secondary glaucoma in the long term. In addition, the use of viscoelastics from methylcellulose does not significantly reduce the development of postoperative hemorrhagic complications, in particular hyphema.

We set the task - to reduce the number of surgical and postoperative complications.

To solve this problem, a viscoelastic based on methylcellulose is proposed, additionally containing dipivephrine hydrochloride and benzalkonium chloride as a stabilizer in the following ratio of components,%:

cellulose 1.5-2.5 dipivephrine hydrochloride 0.0125-0.025 benzalkonium chloride 0.0005-0.001 saline phosphate buffer rest

Viscoelastic is prepared from methyl cellulose, which is the result of the polymerization of modified glucose monomers, which, with stirring, is dissolved in physiological saline balanced with phosphate buffer.

The proposed viscoelastic is prepared as follows.

An exact weighed portion of dipivephrine hydrochloride 0.01875 g and benzalkonium chloride 0.00075 g is taken, dissolved in 100 ml of physiological saline containing phosphate buffer (0.05 M solution of potassium phosphate disubstituted and sodium phosphate monosubstituted) and 2.0 g of methyl cellulose, which with stirring, it gradually dissolves during the day at room temperature. As a result, 1 ml of viscoelastic contains 0.02 g of methyl cellulose, dipivefrin hydrochloride 0.1875 mg, benzalkonium chloride 0.0075 mg and 1 ml of phosphate buffer in physiological saline. The viscosity of the obtained viscoelastic is 4000 Pa / s, which is determined viscometrically. The finished viscoelastic is filtered through a membrane filter, poured into bottles and sterilized by autoclaving (at 0.5 atm and 110 ° C for 30 minutes).

The proposed viscoelastic, when introduced into the anterior chamber during cataract extraction surgery, effectively protects intraocular tissues (corneal endothelium, etc.) during surgical procedures, provides a significant reduction in hemorrhagic complications and a postoperative increase in intraocular pressure due to the pharmacological action of adrenaline resulting from the biotransformation of dipivephrine. In particular, the vasoconstrictor effect of adrenaline helps to reduce the development of hyphema. As a sympathomimetic agent, dipivefrin stimulates the alpha and beta receptors of the ciliary processes, reducing production and increasing the outflow of intraocular fluid, thereby normalizing ophthalmotonus after cataract extraction, if the latter is complicated by postoperative hypertension. In addition, due to the potentiation of the action of atropine, which is used to dilate the pupil during cataract extraction, more effective and stable maintenance of the necessary mydriasis during this surgical intervention is provided. It is practically important that the lipophilic properties of dipivephrine are hundreds of times higher than that of adrenaline, which makes it possible to use it in much lower concentrations than adrenaline, and thereby significantly increase tolerance and reduce the frequency of side effects.

The introduction of the proposed viscoelastic into the anterior chamber to 3 rabbits (6 eyes) during cataract extraction in the experiment did not reveal an irritating or toxic effect with the most thorough postoperative biomicroscopy and ophthalmoscopy for two months.

The proposed viscoelastic is applied by introducing it into the anterior chamber of the eye.

Example 1. Patient M., 52 years old, was admitted with a diagnosis of almost complete complicated cataract of the left eye. Examination data: visual acuity - 0.01 does not correct. The intraocular pressure measured on a pneumotonometer is 19 mmHg. Electrotonography data: P _o - 20.0; C 0.28; F - 1.52; KB - 92. Gonioscopy: the anterior chamber angle is open, the pigmentation of the trabeculae is weak. Objectively: the appendages of the eye are not changed. The cornea is transparent. Front camera of medium depth. The pupil is round, the lens is diffusely cloudy. Deep-lying environments are not ophthalmoscopically.

Under local instillation and retrobulbar anesthesia, the patient underwent cataract extraction with implantation of a posterior intraocular lens and intracameral administration of the proposed viscoelastic. Technique of operation: a diamond blade made a puncture of the cornea at 13 hours. Through it, a 1% solution of mesatone (0.1 ml) was introduced into the anterior chamber. After dilating the pupil, the anterior lens capsule is opened by a cystotome. Corneal incision continued up to 10 hours. The nucleus of the lens is removed in a sliding manner. Produced by washing and aspiration of cataract masses. Using a syringe with a curved cannula, the proposed viscoelastic in the amount of 0.3 ml (containing 2.5% methylcellulose, 0.025% dipivephrine hydrochloride, 0.001% benzalkonium chloride in iso-osmotic phosphate buffer) was introduced into the anterior chamber. After that, the posterior chamber IOL was introduced into the capsular bag. Its alignment is made using a hook. The anterior lens capsule in the optical zone is excised. The front chamber is washed with saline. A continuous suture is placed on the corneal incision. Under the conjunctiva, 0.5 ml of 0.4% dexazone solution and 0.5 ml of gentamicin solution (20 mg) were administered. Complications during and after the operation were not observed.

The patient was discharged on the 6th day of the operation field with a slightly irritated eye, normal pressure (12 mmHg - on a pneumotonometer) and visual acuity of 1.0. A follow-up examination of the patient nine months after the operation showed that the visual acuity of the operated eye remained at the same level - 1.0, the ophthalmotonus was equal to - 17 mm Hg (on a pneumotonometer), hydrodynamic indicators - within normal limits.

Example 2. Patient R., 72 years old, was admitted for surgery with a diagnosis of mature cataract of the left eye.

Upon admission to the hospital: the eye is calm, the cornea is transparent, the anterior chamber is of medium depth, the pupil is round, its reaction to light is weak. The lens is diffusely cloudy. Details of the fundus are not ophthalmoscopic.

Visual acuity - light perception with the correct projection of light. Ophthalmotonus on a pneumotonometer - 19 mmHg Electrotonography data: P _o - 14.0; C 0.38; F is 1.12; KB - 80. With gonioscopy, an open angle of the anterior chamber with slight pigmentation of the trabecula is noted.

The cataract was extracted with the implantation of a posterior intraocular lens and the proposed viscoelastic was introduced into the anterior chamber of the eye. After introducing 0.1 ml of 1% mesatone into the anterior chamber through paracentesis at 13 hours and subsequent expansion of the pupil, the anterior chamber was opened with a cystotome. A corneal incision was made from 13 to 10 hours. The nucleus of the lens is removed in a sliding manner. After washing and aspiration of the lens masses, the proposed viscoelastic in the amount of 0.2 ml (containing 1.5% methylcellulose, 0.0125% dipivefrine hydrochloride, 0.0005% benzalkonium chloride in iso-osmotic phosphate buffer) was introduced into the anterior chamber and an anterior chamber artificial lens was implanted. with partial excision of the anterior capsule. The front chamber is washed with saline. The corneal incision is sutured with a continuous suture. At the end of the operation, 0.5 ml of gentamicin and 0.5 ml of a 0.4% dexazone solution were administered under the conjunctiva of the operated eye. The operation went without complications. In the postoperative period, complications were also not observed.

On the 7th day after the operation, the patient was discharged from the hospital. Visual acuity of the operated eye at discharge 0.9, IOP - 14 mm Hg During the follow-up examination of the patient after 6 months, visual acuity of 1.0, hydrodynamic indicators - without pathology.

Using the proposed viscoelastic surgery, 8 patients (10 eyes) with age-related and complicated cataracts (main group) were operated on. For comparison with the well-known viscoelastic based on methylcellulose - a visitor - 12 people (12 eyes) with age-related and complicated cataracts were operated on (control group). The compared groups were comparable by age and gender of patients, as well as the frequency of common concomitant diseases. It should be noted that in all patients of the main and control groups, as a result of preoperative examination, primary glaucoma was excluded. The follow-up period for patients after surgery is from 6 to 9 months.

In the main group, where cataract extraction, incl. with implantation of a posterior intraocular lens, performed using the proposed viscoelastic, no complications were observed during surgery. Whereas in the control group in 2 cases (16.7%) a hyphema was observed. Moreover, in one case, the occurrence of hyphema was associated with insufficient expansion of the pupil. It is appropriate to note here that the pupil width in the main group during surgery was on average 1.2 mm larger than in the control group.

In the early postoperative period, no hemorrhagic complications were observed in the main group. In no case was hypertension observed in the early postoperative period, and secondary glaucoma in the late. Whereas in the control group in 2 cases (16.7%) in the early postoperative period, a hyphema was observed, which was eliminated as a result of the prescribed absorbable treatment. In 3 cases (25.0%) in the early postoperative period, hypertension was recorded (32-50 mmHg - on a pneumotonometer), which was stopped by local antihypertensive therapy and the use of diacarb. In the long term after surgery, the 1st patient (8.3%) developed secondary glaucoma, which required surgical treatment.

Thus, the use of the proposed viscoelastic in the extraction of cataracts, including using IOL, it contributes to a significant reduction in hemorrhagic complications and hypertension in the early postoperative period and secondary glaucoma in the late.

Claims (1)

Viscoelastic for protecting intraocular tissues of the eye, containing methylcellulose, phosphate buffer, characterized in that it additionally contains dipivefrin hydrochloride and benzalkonium chloride in the following ratio, wt.%: Cellulose 1.5-2.5 Dipivefrina hydrochloride 0.0125-0.025 Benzalkonium chloride 0.0005-0.001 Saline, containing phosphate buffer rest