RU2288677C2 - Method for photodynamic therapy of inflammatory diseases in anterior ocular segment - Google Patents

Abstract

FIELD: medicine, ophthalmology.

SUBSTANCE: through paracentesis in limbic area one should introduce into anterior chamber about 0.2-0.3 ml photosensitizing gel based upon hyaluronic acid viscoelastic taken out of the group of chealon, viscoate or hyatulon. The gel contains 0.2-1.0 weight% photosensitizer of khlorin group chosen out of the group of photolon, radakhlorin or photoditasin. Then it is important to conduct exposition of photosensitizing gel without light access for about 20-30 min. Then it is necessary to apply the gel based upon hyaluronic acid viscoelastic (taken out of the same group) onto corneal surface. Then comes transcorneal laser irradiation of anterior ocular segment with scattered laser radiation at the density of radiation energy being 40-60 J/sq. cm. On finishing photodynamic therapy, one should wash out anterior chamber with physiological solution. In the course of the next 48 h a patient should wear special glasses with a light filter for preventing lateral light and removing the light at wave length of above 600 nm, as well. The innovation interrupts inflammatory process and excludes excessive toxic impact upon anterior ocular segment.

EFFECT: higher efficiency of photodynamic therapy.

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Description

The invention relates to medicine, namely to methods for treating inflammatory diseases of the anterior segment of the eye using photodynamic therapy, for example, chronic sluggish uveitis, iridocyclitis with an exudative reaction.

The objective of the invention is to provide a method of photodynamic therapy of inflammatory diseases of the anterior segment of the eye.

The technical result is the relief of the inflammatory process, the exclusion of excessive toxic effects on the anterior segment of the eye.

The technical result is achieved due to the fact that:

1. used chlorine-type photosensitizers (PS) are characterized by a high degree of purity, low toxicity, and the ability, even in small doses, to exhibit high photodynamic activity under laser irradiation,

2. The antimicrobial effect of photodynamic therapy (PDT) is associated with active selective binding of FS to cells of pathogenic microorganisms; free radicals arising in the PDT process, radical ions, and in particular singlet oxygen damage the plasma membranes and DNA of the cells of pathogenic microorganisms (both gram-positive, ion and gram-negative), leading to the death of these cells, which allows the method to be used without identifying microflora,

3. use a photosensitizing gel (FS gel) containing 0.2-1 wt.% Photosensitizer. This concentration range is necessary and sufficient to achieve the specified technical result.

The method is as follows. Paracentesis is performed in the limb region, the anterior chamber is washed with physiological saline and the anterior chamber is filled with a cannula with a photosensitizing gel based on viscoelastic hyaluronic acid selected from the group of chealon, viscoate or giatulon. The gel contains from 0.2 to 1.0 wt.% Photosensitizer of the chlorin series, selected from the group of photolon, radachlorin or photoditazine. The photosensitizing gel is exposed without light for 20-30 minutes. A gel based on the viscoelastic of hyaluronic acid selected from the group of chealon, viscoate or giatulon is applied to the surface of the cornea, and a laser scattering device is placed on the cornea. Using this device, transcranial laser irradiation of the anterior segment of the eye with laser scattered radiation with a wavelength of 661-666 nm is carried out with a radiation energy density of 40-60 J / cm ² . After the end of photodynamic therapy, the anterior chamber is washed with physiological saline, and the patient uses glasses with a filter for 48 hours to cut off light with a wavelength of more than 600 nm and prevent side light from entering the eye.

Among the essential features characterizing the method of photodynamic therapy of inflammatory diseases of the anterior segment of the eye, the following are distinguishing:

- performance in the field of limb paracentesis,

- filling the front chamber of 0.2-0.3 ml of a photosensitizing gel based on viscoelastic hyaluronic acid selected from the group of chealon, viscoat or giatulon, while the gel contains from 0.2 to 1.0 wt.% photosensitizer of the chlorine series selected from groups of photolon, radachlorin or photoditazine,

- exposure of the photosensitizing gel without access of light for 20-30 minutes,

- applying to the surface of the cornea gel based on viscoelastic hyaluronic acid selected from the group of chealon, viscoate or giatulon,

- placement on the cornea of a laser scattering device,

- carrying out using the transcornal laser irradiation of the anterior eye segment using a transcornal laser irradiation device located on the cornea with scattered laser radiation with a wavelength of 661-666 nm, providing an irradiation energy density of 40-60 J / cm ² ,

- the patient's use after the end of photodynamic therapy and washing of the anterior chamber with physiological saline for 48 hours with glasses with a filter that cuts off light with a wavelength of more than 600 nm and prevents side light from entering the eye.

Experimental studies of the proposed method of photodynamic therapy of inflammatory diseases of the anterior segment of the eye in clinical conditions have shown its high efficiency. A photochemical induced cytotoxic effect on microorganisms without their identification during treatment was achieved, and the effectiveness of treatment with a simultaneous decrease in its duration was increased.

The implementation of the proposed method of photodynamic therapy of inflammatory diseases of the anterior segment of the eye is illustrated by the following clinical examples.

Example 1. Patient M., 48 years old, was admitted to the Kaluga branch of the State Research and Technology Center "Eye Microsurgery" with a diagnosis of "Chronic post-traumatic uveitis of the right eye (at the stage of exacerbation). Visual acuity upon admission - hand movement in the face, correct light projection. Objectively - mixed injection of the eyeball Edema of the epithelium and stroma of the cornea I-II degree Descemetitis, multiple small precipitates on the corneal endothelium. In the anterior chamber Tyndall phenomenon II degree, pupil about 4 mm in diameter, hypopion level up to 1.5 mm, reaction to light absent. re Lex fundus - dim.

The treatment of the inflammatory process was carried out using photodynamic therapy of the anterior segment of the eye. Paracentesis was performed in the limb region, the front chamber was washed with physiological saline and 0.3 ml of a photosensitizing gel based on viscoelastic hyaluronic acid, namely a chealon, was injected into the front chamber, while the gel contains 0.2 wt.% Chlorin-type photosensitizer - photolon. Then, after exposing the photosensitizing gel without light for 30 minutes, a gel based on viscoelastic hyaluronic acid, namely a chealon, was applied to the surface of the cornea, and a laser scattering device was placed on the cornea. The body of the device is made of a cylindrical or conical shape with an internal conical cavity, turning in its upper part into a spherical. The diameter of the base of the internal conical cavity of the device is 11-16 mm, the surface of the conical and spherical parts of the internal cavity of the device is made of scattering and reflecting laser radiation with a light reflectance of 0.6-0.8 and coated with polytetrafluoroethylene. In the device’s body, 1-3 through holes are made for supplying laser radiation to the internal cavity, and a laser prism or a spherical lens is placed in the hole. The lower part of the device is equipped with a removable protective ring made of polymer, metal or glass material. Using the device, transcornal laser irradiation of the anterior segment of the eye was performed with scattered laser radiation with a wavelength of 666 nm with a radiation energy density of 60 J / cm ² . After the end of photodynamic therapy, the anterior chamber was washed with saline. The patient used glasses for 48 hours with a filter that cuts off light with a wavelength of more than 600 nm and prevents side light from entering the eye.

As a result of the treatment, relief of the inflammatory process of the anterior segment of the eye was achieved. Visual acuity increased to 0.2. Objectively: OD is almost calm, the cornea is transparent. The amount of precipitates on the endothelium has decreased significantly. The anterior chamber is of medium depth, the moisture of the anterior chamber is transparent. A pupil with a diameter of 5-6 mm, the reaction to light is alive. The reflex is pink, slightly weakened.

Example 2. Patient A., 18 years old, was admitted to the Kaluga branch of the State Scientific and Practical Center "Eye Microsurgery" with a diagnosis of "Artifact of the left eye. Postoperative exudative iridocyclitis OS". On admission, the visual acuity of the left eye is 0.02. OS moderately irritated, precorneal injection of the eyeball. Edema of the corneal epithelium of the first degree. In the anterior chamber, fibrinous exudate is fixed in the area of the surgical incision, as well as to the pupil of the iris and the anterior chamber of the lens. Thick "Tyndalum" I-II degree, hypopion 1 mm. The pupil is about 4 mm in diameter, practically does not respond to light. The position of the IOL is central. The fundus reflex is sharply weakened.

The treatment of the inflammatory process was carried out using photodynamic therapy of the anterior segment of the eye. Paracentesis was performed in the limb region, the front chamber was washed with physiological saline and 0.2 ml of a photosensitizing gel based on viscoelastic hyaluronic acid, namely a chealon, was injected into the front chamber, while the gel contains 1.0 wt.% Chlorine-type photosensitizer - photoditazine. Then, after exposure of the photosensitizing gel without light for 20 minutes, a gel based on viscoelastic hyaluronic acid, namely viscoate, was applied to the surface of the cornea, and a laser-scattering device was placed on the cornea. The body of the device is made of a cylindrical or conical shape with an internal conical cavity, turning in its upper part into a spherical. The diameter of the base of the internal conical cavity of the device is 11-16 mm, the surface of the conical and spherical parts of the internal cavity of the device is made of scattering and reflecting laser radiation with a light reflectance of 0.6-0.8 and coated with polytetrafluoroethylene. In the device’s body, 1-3 through holes are made for supplying laser radiation to the internal cavity, and a laser prism or a spherical lens is placed in the hole. The lower part of the device is equipped with a removable protective ring made of polymer, metal or glass material. Using the device, transcranial laser irradiation of the anterior segment of the eye was performed with scattered laser radiation with a wavelength of 661 nm with a radiation energy density of 60 J / cm ² . After the end of photodynamic therapy, the anterior chamber was washed with saline. The patient used glasses for 48 hours with a filter that cuts off light with a wavelength of more than 600 nm and prevents side light from entering the eye.

As a result of the treatment, a clinical improvement of the eye condition with relief of the inflammatory process was achieved. When discharged (on the 7th day) objectively, the OS is almost calm. The moisture of the front camera is transparent. The pupil diameter is 6-7 mm (drug mydriasis). There are no posterior synechiae. The position of the IOL is correct. Fundus Reflex - Pink.

Claims (1)

A method for the photodynamic therapy of inflammatory diseases of the anterior segment of the eye, characterized in that paracentesis in the limb region is performed, 0.2-0.3 ml of a photosensitizing gel based on viscoelastic hyaluronic acid selected from the group of chealon, viscoate or hyatulon is introduced into the anterior chamber the gel contains from 0.2 to 1.0 wt.% chlorine-type photosensitizer selected from the group of photolon, radachlorin or photoditazine, the photosensitizing gel is exposed without light for 20-30 minutes, applied to The surface of the cornea is a gel based on viscoelastic hyaluronic acid selected from the chealon, viscoat or giatulon group, and transcranial laser irradiation of the anterior segment of the eye is performed with scattered laser radiation with a radiation energy density of 40-60 J / cm ² , after the end of photodynamic therapy, the anterior chamber is washed with physiological solution, and the patient uses glasses for 48 hours with a filter that cuts off light with a wavelength of more than 600 nm and prevents side light from entering the eye.