RU2274436C1 - Photodynamic method for treating choroid neovascular membranes - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves intravenously introducing photosensibilizer and applying laser radiation. Transpupillary irradiation of choroid neovascular membrane with low intensity laser radiation having wavelength of 633 nm at a dose of 2.5 J and at wavelength of 890 nm at a dose of 1.2 J is applied before intravenously introducing the photosensibilizer. Chlorine row photosensibilizer is intravenously introduced as the photosensibilizer at a dose of 0.5-0.8 mg/kg within 10 min. Transpupillary fluorescent spectral diagnostic of photosensibilizer accumulation in the choroid neovascular membrane is started 1 min later after beginning introducing the photosensibilizer. When detecting choroid neovascular membrane fluorescence in comparison to the surrounding tissues, intravenous laser irradiation of blood is started using wavelength equal to maximum light radiation absorption by the photosensibilizer during 5-15 min at radiation power equal to 20-50 mW.

EFFECT: enhanced effectiveness of treatment; dosed treatment procedures; destroyed neoplasm blood vessels and prevented their growth.

3 cl

Description

The invention relates to medicine, and more specifically to ophthalmology, and can be used for the treatment of choroidal neovascular membranes of various etiologies.

A known method of photodynamic therapy of choroidal neovascular membranes (Axer-Siegel R, Ehrlich R, Yassur Y, Rosenblatt I, Kramer M, Priel E, Benjamini Y, Weinberger D. Photodynamic therapy for age-related macular degeneration in a clinical setting: visual results and angiographic patterns // Am J Ophthalmol. 2004 Feb; 137 (2): 258-64), including intravenous administration of a photosensitizer (PS) and laser irradiation.

However, the use of this method in some cases is accompanied by the development of severe retinal edema and hemorrhage due to extensive hemorrhagic necrosis, which leads to a sharp decrease in vision. Due to the lack of preliminary spectral-fluorescence diagnostics, photodynamic therapy in this method is ineffective: large laser radiation powers lead to the above complications, and small ones to the absence of a therapeutic effect. In addition, when using this method, in order to achieve a stable therapeutic effect, several repeated sessions are necessary, which inevitably leads to damage to the photoreceptor apparatus of the eye as a result of the induced photochemical reaction and, as a result, to a decrease in vision. The inability to diagnose to determine the accumulation of PS in the choroidal neovascular membrane does not allow us to choose the optimal dose of laser radiation to achieve an adequate therapeutic effect.

The technical result is an increase in the effectiveness of photodynamic therapy in the treatment of choroidal neovascular membranes, dosed treatment sessions, the destruction of newly formed vessels and the prevention of their growth, complete arrest of neovascular tissue growth. The technical result is achieved due to the fact that:

1. Transpupillary irradiation of the choroidal neovascular membrane with low-intensity laser radiation prior to intravenous administration of FS improves blood microcirculation in the irradiated area, which leads to a more intensive flow of PS into the neovascular tissue;

2. The chlorine-type photosensitizers (PSs) used are characterized by a high degree of purity, low toxicity, and the ability to accumulate in cells with high mitotic activity, in particular in endothelial cells of newly formed vessels, and even in small doses exhibit high photochemical activity under laser irradiation;

3. Carrying out transpupillary spectral-fluorescence diagnostics allows us to determine whether there was sufficient and necessary for the therapeutic effect of the accumulation of the photosensitizer in the choroidal neovascular membrane compared with the surrounding tissue;

4. With intravenous laser irradiation with a wavelength corresponding to the maximum absorption of PS laser irradiation, there is selective damage to the endothelium of the newly formed vessels of the choroidal neovascular membrane, leading to their occlusion, without damage to the retinal pigment epithelium and the outer nuclear layer of the retina;

5. Intravenous laser irradiation allows for a slow and gradual course of a photo-induced chemical reaction without the occurrence of destructive changes;

6. The used ranges of the dose of FS and the power of intravenous laser irradiation are necessary and sufficient for the implementation of the photoinduced photochemical reaction to obtain the therapeutic effect necessary to achieve the specified technical result.

The claimed technical result can be obtained only by using the totality of the techniques proposed by us method.

The method is as follows. Carry out a transpupillary irradiation of the choroidal neovascular membrane with low-intensity laser radiation with a wavelength of 633 nm at a dose of 2.5 J or with a wavelength of 890 nm at a dose of 1.2 J. Then a chlorine-type photosensitizer, for example, photolon, radachlorin, photoditazine, is administered at a dose of 0 5-0.8 mg / kg for 10 minutes. One minute after the start of intravenous administration of PS, a transpupillary spectral fluorescence diagnosis of PS accumulation in the choroidal neovascular membrane is started, for example, using a laser spectroscopic complex based on a standard slit lamp (Loshchenov V.B., Meerovich G.A., Shevchik S. A. et al. Laser-spectroscopic complex for fluorescence diagnostics and photodynamic therapy of pathologies of the posterior parts of the eye // Actual aspects of laser medicine: Materials of scientific and practical conferences of Russian scientists x, Moscow, Kaluga, 3-5 October 2002). - Moscow-Kaluga, 2002 .-- S.343-344). The registration of fluorescence is carried out, for example, using an interference filter with a transmission range of 665-800 nm. In the course of spectral-fluorescence diagnostics, the contrast of PS accumulation in the choroidal neovascular membrane is monitored and, when fluorescence of the choroidal neovascular membrane appears, compared with the surrounding tissue, intravenous laser irradiation of blood is performed with a wavelength corresponding to the maximum absorption of light photosensitizer, for example, with a wavelength of 66066 nm when using FS chlorin series, for 5-15 minutes at a power of 20-50 mW.

The technique is repeated in full with the same parameters after 3-4 days.

All actions with the photosensitizer are carried out in a dark environment, ensuring the inability to penetrate into the room in direct sunlight. This condition is well known and standard for PDT sessions.

The invention is illustrated by the following examples.

Example 1. Patient T., 65 years old. Upon admission to the Kaluga branch of the State Medical Research Center "Eye Microsurgery", the choroidal neovascular membrane (HNVM) of the right eye was diagnosed, which developed against the background of age-related macular degeneration.

The initial visual acuity at the time of treatment was on the OD - 0.05 n / k, on the OS - 0.32 n / k. Foveolar sensitivity OD - 11 dB, OS - 24 dB, respectively. When examining the fundus OD - in the macular region, a round shape of the focal area with fuzzy borders (exudative detachment of the neuroepithelium) with pronounced perifocal hemorrhages was determined. Carrying out fluorescence angiography of the fundus (FAG) revealed the presence of an extensive hidden choroidal neovascular membrane of subfoveal localization. On the paired eye in the macular region there were dystrophic changes of a non-exudative nature in the form of multiple druze and dispersion.

The patient is treated according to the proposed method.

We performed transpupillary irradiation of the choroidal neovascular membrane with low-intensity laser radiation with a wavelength of 633 nm at a dose of 2.5 J. Photolon was administered intravenously at a dose of 0.5 mg / kg. A transpupillary spectral fluorescence diagnosis of PS accumulation in the choroidal neovascular membrane was performed. Intravenous laser irradiation of blood was performed with a wavelength of 660 nm for 5 minutes at a power of 50 mW.

The procedure was repeated in full with the same parameters after 3 days.

At the control examination after 1 month, the visual acuity of OD was 0.1 n / K. Foveolar sensitivity 18 dB. When examining the fundus of the eye, OD, there was a positive trend in the form of a significant reduction in subretinal edema and hemorrhages. By the age of 3 months, visual acuity increased to 0.2 n / a, foveal sensitivity up to 22 dB. Ophthalmoscopically - a flat fibrous lesion was formed in the macular region, subretinal edema and hemorrhages completely resolved. According to the control phage, complete obliteration of the newly formed choroidal neovascular network was determined. In the observation period of up to 1.5 years, relapses in the development of HNVM were not noted.

Example 2. Patient P., 67 years old. Upon admission to the Kaluga branch of the State Medical Research Center "Eye Microsurgery", a choroidal neovascular membrane (HNVM) of the left eye was diagnosed, which developed against the background of age-related macular degeneration.

The initial visual acuity at the time of treatment was 0.4 n / k on OD, 0.05 n / k on OS. Foveolar sensitivity OD - 23 dB, OS - 12 dB, respectively. When examining the fundus of the OS - in the macular region, a round shape of the proging lesion with fuzzy borders (exudative detachment of the neuroepithelium) with pronounced perifocal hemorrhages was determined. Carrying out fluorescence angiography of the fundus (FAG) revealed the presence of an extensive hidden choroidal neovascular membrane of subfoveal localization.

The patient is treated according to the proposed method.

We performed transpupillary irradiation of the choroidal neovascular membrane with low-intensity laser radiation with a wavelength of 890 nm at a dose of 1.2 J. Radachlorin was administered intravenously at a dose of 0.8 mg / kg. A transpupillary spectral fluorescence diagnosis of PS accumulation in the choroidal neovascular membrane was performed. Intravenous laser irradiation of blood was performed with a wavelength of 666 nm for 15 minutes at a power of 20 mW.

The procedure was repeated in full with the same parameters after 4 days.

At the control examination after 1 month, the visual acuity of the OS was 0.1 n / K. Foveolar sensitivity 17 dB. When examining the fundus on the OS, there was a positive trend in the form of a significant reduction in subretinal edema and hemorrhages. By the age of 3 months, visual acuity increased to 0.2 n / a, foveal sensitivity up to 21 dB. Ophthalmoscopically - in the macular region a flat fibrous lesion was formed, subretinal edema and hemorrhages completely resolved. According to the control phage, complete obliteration of the newly formed choroidal neovascular network was determined. In the observation period of up to 2 years, recurrence of the development of HNVM was not observed.

Thus, the proposed method increases the effectiveness of photodynamic therapy in the treatment of choroidal neovascular membranes, provides dosed treatment sessions and leads to a complete stop of the growth of neovascular tissue.

Claims (3)

1. The method of photodynamic therapy of choroidal neovascular membranes, including intravenous administration of a photosensitizer (PS) and laser irradiation, characterized in that prior to intravenous administration of a FS, transpillary irradiation of the choroidal neovascular membrane with low-intensity laser radiation with a wavelength of 633 nm at a dose of 2.5 J or 2.5 J or a wavelength of 890 nm in a dose of 1.2 J, and FS of the chlorin series at a dose of 0.5-0.8 mg / kg is administered as a PS for 10 minutes, one minute after the start of PS administration, transpupillary is started spectral fluorescence diagnostics (SFD) of PS accumulation in the choroidal neovascular membrane, and when fluorescence of the choroidal neovascular membrane appears compared to the surrounding tissue, an intravenous laser irradiation of blood with a wavelength corresponding to the maximum absorption of light by a photosensitizer is carried out for 5-15 minutes power of 20-50 mW. 2. The method according to claim 1, characterized in that the registration of fluorescence is carried out using an interference filter with a transmission range of 665-800 nm. 3. The method according to claim 1 or 2, characterized in that after 3-4 days the transpupillary irradiation of the choroidal neovascular membrane with low-intensity laser radiation is repeated, intravenous administration of FS, spectral fluorescence diagnostics, intravenous laser irradiation of blood with the same parameters.