RU2801497C1 - Method of cataract extraction with intraocular lens implantation in patients after the second stage of keratoprosthetics - Google Patents

Abstract

FIELD: medicine, ophthalmology.

SUBSTANCE: cataract extraction is performed with intraocular lens implantation in patients after the second stage of keratoprosthetics. Viscoelastic is introduced, circular capsulorhexis, hydrodissection, hydrodelineation and implantation of an intraocular lens into the capsular bag are performed. The newly formed vessels are coagulated in the projection of the limbus in the area of the planned incisions. Further, in the projection of the limbus at 11 o’clock position, a main incision of 2.2 mm in size and two paracentesis in the projection of the limbus of 1.5 mm in size at 2 and 9 o’clock position, respectively, are made, after which a cohesive viscoelastic is introduced into the anterior chamber, which during the operation as it exits from the anterior chamber is added, replenishing its volume. Then, using collet tweezers, a circular capsulorhexis is performed, the diameter of which corresponds to the diameter of the optical cylinder, that is 3.5 mm. Hydrodissection and hydrodelineation are performed by supplying saline with a flat cannula, after which the lens nucleus is crushed using a phaco needle and cataract phacoemulsification is performed using a sparing regimen: the height of the irrigation tank is 50 cm or less; vacuum less than 100 mm Hg; ultrasound — 80 pulses per minute with a fractional feed and a power of less than 30%. Next, the removal of the epinucleus and residual cortical masses is performed using an irrigation-aspiration system and a Simcoe cannula, after which a cohesive viscoelastic is introduced into the capsular bag and an intraocular lens is implanted into the capsular bag using a manual injector, centered and the residual viscoelastic is washed out, after which all incisions are sealed by placing interrupted sutures.

EFFECT: method allows to reduce the risk of intraoperative complications by maintaining a sealed anterior chamber.

1 cl, 1 ex

Description

A method for cataract extraction with intraocular lens implantation in patients after the second stage of keratoprosthetics.

The invention relates to medicine, and more specifically to ophthalmology, and can be used for cataract (EC) extraction in patients in a delayed period after the second stage of keratoprosthetics.

Keratoprosthetics is the only possible way to restore visual functions in patients with vascular cataracts of category 4-5 (according to the classification of V.P. Filatov - D.G. Bushmich, 1947). One of the common comorbidities in patients with vascular leukomas is cataract, which is diagnosed both during keratoprosthetics and after keratoprosthetics in the long-term period. EC in such cases has its own characteristics and often requires extremely complex manipulations.

A known method of EC in a patient after keratoprosthetics, which is the closest analogue of the claimed method (Harissi-Dagher M., Colby K.A. Cataract extraction after implantation of a type I Boston keratoprosthesis // Cornea. - 2008. - Vol. 27, No. 2 - P. 220-222).

The method consists in dissecting the sutures after penetrating keratoprosthetics and completely removing the keratoprosthetic complex consisting of a graft and a keratoprosthesis implanted into it with an optical cylinder. The removed keratoprosthetic complex is placed in a medium for preserving the cornea and then proceed to EC, which is carried out by an extracapsular method: a circular capsulorhexis with a diameter of 4.5 mm is performed, hydrodissection, hydrodelineation, and lens masses are washed out. Next, a cohesive viscoelastic is introduced into the capsular bag and an intraocular lens (IOL) is implanted. The operation is completed by removing the keratoprosthetic complex from the medium for preserving the cornea and fixing it with interrupted sutures to the recipient's cornea.

The disadvantages of the method: the absence of the anterior chamber when performing EC, due to the removal of the keratoprosthetic complex; the impossibility of rapid sealing with the onset of ophthalmohypertension, due to the large diameter of the hole that remains after the removal of the keratoprosthetic complex; the risk of injury to the posterior lens capsule and the anterior hyaloid membrane, as well as the risk of developing expulsive hemorrhage, which is associated with the absence of the anterior chamber and the possibility of displacement of the intraocular structures forward during EC.

The objective of the invention is to create a method of EC with IOL implantation in patients after the second stage of keratoprosthetics, which allows you to perform EC with the presence of the anterior chamber and restore visual functions to the maximum by implanting an IOL of the required optical power.

The technical result of this method is the possibility of EC in patients after the second stage of keratoprosthetics, reducing the risk of intraoperative complications by maintaining a sealed anterior chamber, as well as the ability to calculate the most accurate optical power of the IOL based on the optical power of the cylinder, the length of the eyeball and standard keratometric parameters, which allows you to speed up the visual rehabilitation of the patient.

The method is carried out as follows.

The newly formed vessels are coagulated in the projection of the limbus in the area of the planned incisions (2, 9 and 11 hours). In the projection of the limbus at 11 o'clock, a main incision is made, 2.2 mm in size, and two paracentesis in the projection of the limbus, 1.5 mm in size, at 2 and 9 o'clock, respectively. The location of the incisions provides the surgeon with a convenient location for the instruments needed for EC and IOL implantation. Next, a cohesive viscoelastic is introduced into the anterior chamber, which is added during the operation as it leaves the anterior chamber, replenishing its volume. Then, using collet tweezers, a circular capsulorhexis is performed, the diameter of which corresponds to the diameter of the optical cylinder - 3.5 mm. Using a flat cannula, hydrodissection and hydrodelineation are performed by supplying saline. To perform phacoemulsification, a phaco machine from Alcon (USA) is used. Using a phaco-needle, the lens nucleus is crushed and cataract phacoemulsification is performed using a sparing regimen: the height of the irrigation tank is 50 cm or less; vacuum less than 100 mm Hg; ultrasound - 80 pulses per minute with a fractional feed and a power of less than 30%. After removal of the lens nucleus, the epinucleus and residual cortical masses are removed using an irrigation-aspiration system and a Simcoe cannula. Further, after EC, a cohesive viscoelastic is introduced into the capsular bag and, using a manual injector Monarch lll (USA), an IOL is implanted into the capsular bag through the main incision. The optical power of the IOL is calculated using the Barrett Universal ll Formula, taking into account the optical power of the cylinder, the length of the eyeball and standard keratometric parameters. After implantation, the IOL is centered and the residual viscoelastic is washed out using an irrigation-aspiration system and a Simcoe cannula. At the end of the operation, all incisions are sealed by interrupted sutures.

Significant differences of this method:

the method allows you to save the anterior chamber when performing EC due to the minimum size of the main incision - 2.2 mm and two paracentesis, 1.5 mm in size, which makes it possible to quickly seal the anterior chamber;

the method allows to reduce intraoperative risks associated with EC due to the use of a sparing regimen during phacoemulsification;

the method allows to speed up the patient's visual rehabilitation by implanting an IOL, the diopter of which is calculated individually, taking into account the length of the eyeball, standard keratometric parameters and optical power of the cylinder.

The method is illustrated by the following example.

Patient A., 71 years old. Diagnosis: OS Vascular leukoma of the cornea. The outcome of a chemical burn. Condition after the second stage of keratoprosthetics. Complicated cataract. OD Anophthalmos.

From the anamnesis it is known that 6 years ago he received an industrial lime burn in both eyes. At the place of residence, the right eye was enucleated immediately after the burn. 2 years ago, the second stage of keratoprosthetics in the left eye was performed at the MNTK MG. Visual acuity at discharge 0.4 with correction sph -3.0=0.8.

Biomicroscopy of the left eye visualizes a vascularized corneal leukoma, a centrally located optical cylinder, complete clouding of the lens in the nucleus and cortical layers. Deep-lying media are not ophthalmoscoped.

Visual acuity: OS - 1/∞ proectia lucis certa. Intraocular pressure was normal on palpation.

With optical coherence tomography (OCT) of the anterior segment of the left eye, the keratoprosthesis occupies the correct central position.

According to the electrophysiological study revealed minor changes in the left eye.

According to the B-scan: the membranes of the left eye are adjacent, the destruction of the vitreous body.

Taking into account the potential of visual functions, as well as the correct central position of the keratoprosthesis according to OCT data and the presence of a complicated cataract, it was decided to perform EC with IOL implantation according to the proposed method. The optical power of the IOL was calculated using the Barrett Universal II Formula, taking into account the length of the eyeball, standard keratometric parameters, and the optical power of the cylinder.

The course of the early postoperative period was uneventful. Moderate edema and hyperemia were noted in the first days.

Visual acuity of the left eye was 0.3 without correction. Intraocular pressure was normal on palpation.

At discharge from the hospital on the 7th day: the eye is calm, the sutures are well-founded. Visual acuity: 0.5 with correction sph -1.0=0.7. Intraocular pressure was normal on palpation.

When examining the patient after 3 months, the eye is calm. Visual acuity: 0.6 with correction sph -0.5=0.8. Intraocular pressure was normal on palpation.

After 6 months, when examined, the eyes are calm. According to OCT, the keratoprosthesis occupies the correct central position. Visual acuity: 0.6 with correction sph -0.5=0.8. Intraocular pressure was normal on palpation.

The proposed version of the method was used in two clinical cases. In each of them, it was possible to achieve maximum restoration of visual functions.

Claims (1)

A method for cataract extraction with intraocular lens implantation in patients after the second stage of keratoprosthetics, including the introduction of viscoelastic, circular capsulorhexis, hydrodissection, hydrodelineation and implantation of the intraocular lens into the capsular bag, characterized in that coagulation of newly formed vessels is performed in the projection of the limbus in the area of planned incisions, further in the projection of the limbus at 11 o'clock, a main incision of 2.2 mm in size and two paracentesis in the projection of the limbus of 1.5 mm in size at 2 and 9 o'clock, respectively, are made, after which a cohesive viscoelastic is introduced into the anterior chamber, which during the operation, as it exits from the anterior chamber is added to replenish its volume, then, using collet tweezers, a circular capsulorhexis is performed, the diameter of which corresponds to the diameter of the optical cylinder - 3.5 mm, hydrodissection and hydrodelineation are performed by supplying saline with a flat cannula, after which the nucleus is crushed using a phaco needle lens and cataract phacoemulsification is performed using a gentle mode: the height of the irrigation tank is 50 cm or less; vacuum less than 100 mm Hg; ultrasound - 80 pulses per minute with fractional flow and power less than 30%; then the removal of the epinucleus and residual cortical masses is performed using an irrigation-aspiration system and a Simcoe cannula, after which a cohesive viscoelastic is introduced into the capsular bag and an intraocular lens is implanted into the capsular bag using a manual injector, centered and the residual viscoelastic is washed out, after which all incisions are sealed by placing interrupted sutures.